diff --git a/src/config.cpp b/src/config.cpp
index 2ee7ef357..cae2eade3 100644
--- a/src/config.cpp
+++ b/src/config.cpp
@@ -1,52 +1,49 @@
 // Copyright (c) 2017-2019 The Bitcoin developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <config.h>
 
 #include <chainparams.h>
 #include <consensus/consensus.h> // DEFAULT_MAX_BLOCK_SIZE
 
 GlobalConfig::GlobalConfig()
     : useCashAddr(false), nMaxBlockSize(DEFAULT_MAX_BLOCK_SIZE) {}
 
 bool GlobalConfig::SetMaxBlockSize(uint64_t maxBlockSize) {
     // Do not allow maxBlockSize to be set below historic 1MB limit
     // It cannot be equal either because of the "must be big" UAHF rule.
     if (maxBlockSize <= LEGACY_MAX_BLOCK_SIZE) {
         return false;
     }
 
     nMaxBlockSize = maxBlockSize;
     return true;
 }
 
 uint64_t GlobalConfig::GetMaxBlockSize() const {
     return nMaxBlockSize;
 }
 
 const CChainParams &GlobalConfig::GetChainParams() const {
     return Params();
 }
 
 static GlobalConfig gConfig;
 
 const Config &GetConfig() {
     return gConfig;
 }
 
 void GlobalConfig::SetCashAddrEncoding(bool c) {
     useCashAddr = c;
 }
 bool GlobalConfig::UseCashAddrEncoding() const {
     return useCashAddr;
 }
 
 DummyConfig::DummyConfig()
     : chainParams(CreateChainParams(CBaseChainParams::REGTEST)) {}
 
 DummyConfig::DummyConfig(std::string net)
     : chainParams(CreateChainParams(net)) {}
-
-DummyConfig::DummyConfig(std::unique_ptr<CChainParams> chainParamsIn)
-    : chainParams(std::move(chainParamsIn)) {}
diff --git a/src/config.h b/src/config.h
index 1cb81babe..214e9fbc1 100644
--- a/src/config.h
+++ b/src/config.h
@@ -1,67 +1,66 @@
 // Copyright (c) 2017 Amaury SÉCHET
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_CONFIG_H
 #define BITCOIN_CONFIG_H
 
 #include <consensus/amount.h>
 #include <feerate.h>
 
 #include <cstdint>
 #include <memory>
 #include <string>
 
 class CChainParams;
 
 class Config {
 public:
     virtual bool SetMaxBlockSize(uint64_t maxBlockSize) = 0;
     virtual uint64_t GetMaxBlockSize() const = 0;
     virtual const CChainParams &GetChainParams() const = 0;
     virtual void SetCashAddrEncoding(bool) = 0;
     virtual bool UseCashAddrEncoding() const = 0;
 
     Config() = default;
     Config(const Config &) = delete;
     Config &operator=(const Config &) = delete;
 };
 
 class GlobalConfig final : public Config {
 public:
     GlobalConfig();
     bool SetMaxBlockSize(uint64_t maxBlockSize) override;
     uint64_t GetMaxBlockSize() const override;
     const CChainParams &GetChainParams() const override;
     void SetCashAddrEncoding(bool) override;
     bool UseCashAddrEncoding() const override;
 
 private:
     bool useCashAddr;
 
     /** The largest block size this node will accept. */
     uint64_t nMaxBlockSize;
 };
 
 // Dummy for subclassing in unittests
 class DummyConfig : public Config {
 public:
     DummyConfig();
     explicit DummyConfig(std::string net);
-    explicit DummyConfig(std::unique_ptr<CChainParams> chainParamsIn);
     bool SetMaxBlockSize(uint64_t maxBlockSize) override { return false; }
     uint64_t GetMaxBlockSize() const override { return 32'000'000; }
 
     const CChainParams &GetChainParams() const override { return *chainParams; }
 
     void SetCashAddrEncoding(bool) override {}
     bool UseCashAddrEncoding() const override { return false; }
 
 private:
     std::unique_ptr<CChainParams> chainParams;
 };
 
 // Temporary woraround.
 const Config &GetConfig();
 
 #endif // BITCOIN_CONFIG_H
diff --git a/src/test/checkpoints_tests.cpp b/src/test/checkpoints_tests.cpp
index 8e4f54831..1d7aecf26 100644
--- a/src/test/checkpoints_tests.cpp
+++ b/src/test/checkpoints_tests.cpp
@@ -1,227 +1,189 @@
 // Copyright (c) 2011-2015 The Bitcoin Core developers
 // Copyright (c) 2018-2019 The Bitcoin developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 //
 // Unit tests for block-chain checkpoints
 //
 
 #include <checkpoints.h>
 
 #include <chain.h>
 #include <chainparams.h>
 #include <config.h>
 #include <consensus/validation.h>
 #include <streams.h>
 #include <uint256.h>
 #include <util/strencodings.h>
 #include <validation.h>
 
 #include <test/util/setup_common.h>
 
 #include <boost/test/unit_test.hpp>
 
 #include <memory>
 
-BOOST_AUTO_TEST_SUITE(checkpoints_tests)
+BOOST_FIXTURE_TEST_SUITE(checkpoints_tests, TestingSetup)
 
-BOOST_FIXTURE_TEST_CASE(sanity, TestingSetup) {
+BOOST_AUTO_TEST_CASE(sanity) {
     const auto params = CreateChainParams(CBaseChainParams::MAIN);
     const CCheckpointData &checkpoints = params->Checkpoints();
     BlockHash p11111 = BlockHash::fromHex(
         "0000000069e244f73d78e8fd29ba2fd2ed618bd6fa2ee92559f542fdb26e7c1d");
     BlockHash p134444 = BlockHash::fromHex(
         "00000000000005b12ffd4cd315cd34ffd4a594f430ac814c91184a0d42d2b0fe");
     BOOST_CHECK(Checkpoints::CheckBlock(checkpoints, 11111, p11111));
     BOOST_CHECK(Checkpoints::CheckBlock(checkpoints, 134444, p134444));
 
     // Wrong hashes at checkpoints should fail:
     BOOST_CHECK(!Checkpoints::CheckBlock(checkpoints, 11111, p134444));
     BOOST_CHECK(!Checkpoints::CheckBlock(checkpoints, 134444, p11111));
 
     // ... but any hash not at a checkpoint should succeed:
     BOOST_CHECK(Checkpoints::CheckBlock(checkpoints, 11111 + 1, p134444));
     BOOST_CHECK(Checkpoints::CheckBlock(checkpoints, 134444 + 1, p11111));
 }
 
-class ChainParamsWithCheckpoints : public CChainParams {
-public:
-    ChainParamsWithCheckpoints(const CChainParams &chainParams,
-                               CCheckpointData &checkpoints)
-        : CChainParams(chainParams) {
-        checkpointData = checkpoints;
-    }
-};
-
-class MainnetConfigWithTestCheckpoints : public DummyConfig {
-public:
-    MainnetConfigWithTestCheckpoints() : DummyConfig(createChainParams()) {}
-
-    static std::unique_ptr<CChainParams> createChainParams() {
-        CCheckpointData checkpoints = {
-            .mapCheckpoints = {
-                {2, BlockHash::fromHex("000000006a625f06636b8bb6ac7b960a8d03705"
-                                       "d1ace08b1a19da3fdcc99ddbd")},
-            }};
-        const auto mainParams = CreateChainParams(CBaseChainParams::MAIN);
-        return std::make_unique<ChainParamsWithCheckpoints>(*mainParams,
-                                                            checkpoints);
-    }
-};
-
-static const MainnetConfigWithTestCheckpoints g_config{};
-
-struct CheckpointsTestingSetup : public TestingSetup {
-    CheckpointsTestingSetup()
-        : TestingSetup{CBaseChainParams::MAIN, /*extra_args=*/{},
-                       /*coins_db_in_memory=*/true,
-                       /*block_tree_db_in_memory=*/true, g_config} {}
-};
-
 /**
  * This test has 4 precomputed blocks mined ontop of the genesis block:
  *  G ---> A ---> AA (checkpointed)
  *   \       \
  *    \--> B  \-> AB
  * After the node has accepted only A and AA, these rejects should occur:
  *  * B should be rejected for forking prior to an accepted checkpoint
  *  * AB should be rejected for forking at an accepted checkpoint
  */
-BOOST_FIXTURE_TEST_CASE(ban_fork_prior_to_and_at_checkpoints,
-                        CheckpointsTestingSetup) {
-    const Config &config = m_node.chainman->GetConfig();
-    assert(std::addressof(config) == std::addressof(g_config));
-
+BOOST_AUTO_TEST_CASE(ban_fork_prior_to_and_at_checkpoints) {
+    const CCheckpointData test_checkpoints = {
+        .mapCheckpoints = {{2, BlockHash::fromHex(
+                                   "000000006a625f06636b8bb6ac7b960a8d03705"
+                                   "d1ace08b1a19da3fdcc99ddbd")}},
+    };
     const CBlockIndex *pindex = nullptr;
 
     // Start with mainnet genesis block
-    CBlockHeader headerG = config.GetChainParams().GenesisBlock();
+    CBlockHeader headerG = Assert(m_node.chainman)->GetParams().GenesisBlock();
     BOOST_CHECK(headerG.GetHash() ==
                 uint256S("000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f"
                          "1b60a8ce26f"));
 
     {
         BlockValidationState state;
-        BOOST_CHECK(
-            Assert(m_node.chainman)
-                ->ProcessNewBlockHeaders({headerG}, true, state, &pindex));
+        BOOST_CHECK(m_node.chainman->ProcessNewBlockHeaders(
+            {headerG}, true, state, &pindex, test_checkpoints));
         pindex = nullptr;
     }
 
     CBlockHeader headerA, headerB, headerAA, headerAB;
     CDataStream stream = CDataStream(
         ParseHex(
             "010000006fe28c0ab6f1b372c1a6a246ae63f74f931e8365e15a089c68d6190000"
             "000000982051fd1e4ba744bbbe680e1fee14677ba1a3c3540bf7b1cdb606e85723"
             "3e0e61bc6649ffff001d01e3629901010000000100000000000000000000000000"
             "00000000000000000000000000000000000000ffffffff0704ffff001d0104ffff"
             "ffff0100f2052a0100000043410496b538e853519c726a2c91e61ec11600ae1390"
             "813a627c66fb8be7947be63c52da7589379515d4e0a604f8141781e62294721166"
             "bf621e73a82cbf2342c858eeac00000000"),
         SER_NETWORK, PROTOCOL_VERSION);
     stream >> headerA;
     BOOST_CHECK(headerA.GetHash() ==
                 uint256S("00000000839a8e6886ab5951d76f411475428afc90947ee320161"
                          "bbf18eb6048"));
     BOOST_CHECK(headerA.hashPrevBlock == headerG.GetHash());
 
     stream = CDataStream(
         ParseHex(
             "010000004860eb18bf1b1620e37e9490fc8a427514416fd75159ab86688e9a8300"
             "000000d5fdcc541e25de1c7a5addedf24858b8bb665c9f36ef744ee42c316022c9"
             "0f9bb0bc6649ffff001d08d2bd6101010000000100000000000000000000000000"
             "00000000000000000000000000000000000000ffffffff0704ffff001d010bffff"
             "ffff0100f2052a010000004341047211a824f55b505228e4c3d5194c1fcfaa15a4"
             "56abdf37f9b9d97a4040afc073dee6c89064984f03385237d92167c13e236446b4"
             "17ab79a0fcae412ae3316b77ac00000000"),
         SER_NETWORK, PROTOCOL_VERSION);
     stream >> headerAA;
     BOOST_CHECK(headerAA.GetHash() ==
                 uint256S("000000006a625f06636b8bb6ac7b960a8d03705d1ace08b1a19da"
                          "3fdcc99ddbd"));
     BOOST_CHECK(headerAA.hashPrevBlock == headerA.GetHash());
 
     stream = CDataStream(
         ParseHex(
             "000000206fe28c0ab6f1b372c1a6a246ae63f74f931e8365e15a089c68d6190000"
             "000000bff4e0fd76ec3e9c8853811dec34dda8d5debb24d4113d94235fd4b24bb2"
             "92981b70995cffff001d4e6e050001020000000100000000000000000000000000"
             "00000000000000000000000000000000000000ffffffff0d51026302082f454233"
             "322e302fffffffff0100f2052a01000000232103c91f2fa16c94c92d08629eeb8f"
             "d681658d49f2b3016b13336d67d79f858dbc71ac000000001"),
         SER_NETWORK, PROTOCOL_VERSION);
     stream >> headerB;
     BOOST_CHECK(headerB.hashPrevBlock == headerG.GetHash());
 
     stream = CDataStream(
         ParseHex(
             "000000204860eb18bf1b1620e37e9490fc8a427514416fd75159ab86688e9a8300"
             "0000003800b1dd09f3f1a1c9e62ce8dca6d1e6caacc9a02d178ef6ad95527b49ff"
             "863f8282995cffff001d2cc70f0001020000000100000000000000000000000000"
             "00000000000000000000000000000000000000ffffffff0d52024902082f454233"
             "322e302fffffffff0100f2052a010000002321020a56690eb0e2454c1f362d3599"
             "89198a0b23505578be4164a65521ee7751eb1dac00000000"),
         SER_NETWORK, PROTOCOL_VERSION);
     stream >> headerAB;
     BOOST_CHECK(headerAB.hashPrevBlock == headerA.GetHash());
 
     // Headers A and AA should be accepted
     {
         BlockValidationState state;
-        BOOST_CHECK(
-            Assert(m_node.chainman)
-                ->ProcessNewBlockHeaders({headerA}, true, state, &pindex));
+        BOOST_CHECK(m_node.chainman->ProcessNewBlockHeaders(
+            {headerA}, true, state, &pindex, test_checkpoints));
         BOOST_CHECK(state.IsValid());
         BOOST_CHECK(pindex != nullptr);
         pindex = nullptr;
     }
 
     {
         BlockValidationState state;
-        BOOST_CHECK(
-            Assert(m_node.chainman)
-                ->ProcessNewBlockHeaders({headerAA}, true, state, &pindex));
+        BOOST_CHECK(m_node.chainman->ProcessNewBlockHeaders(
+            {headerAA}, true, state, &pindex, test_checkpoints));
         BOOST_CHECK(state.IsValid());
         BOOST_CHECK(pindex != nullptr);
         pindex = nullptr;
     }
 
     // Header B should be rejected
     {
         BlockValidationState state;
-        BOOST_CHECK(
-            !Assert(m_node.chainman)
-                 ->ProcessNewBlockHeaders({headerB}, true, state, &pindex));
+        BOOST_CHECK(!m_node.chainman->ProcessNewBlockHeaders(
+            {headerB}, true, state, &pindex, test_checkpoints));
         BOOST_CHECK(state.IsInvalid());
         BOOST_CHECK(state.GetRejectReason() == "bad-fork-prior-to-checkpoint");
         BOOST_CHECK(pindex == nullptr);
     }
 
     // Sanity check to ensure header was not saved in memory
     {
         LOCK(cs_main);
         BOOST_CHECK(m_node.chainman->m_blockman.LookupBlockIndex(
                         headerB.GetHash()) == nullptr);
     }
 
     // Header AB should be rejected
     {
         BlockValidationState state;
-        BOOST_CHECK(
-            !Assert(m_node.chainman)
-                 ->ProcessNewBlockHeaders({headerAB}, true, state, &pindex));
+        BOOST_CHECK(!m_node.chainman->ProcessNewBlockHeaders(
+            {headerAB}, true, state, &pindex, test_checkpoints));
         BOOST_CHECK(state.IsInvalid());
         BOOST_CHECK(state.GetRejectReason() == "checkpoint mismatch");
         BOOST_CHECK(pindex == nullptr);
     }
 
     // Sanity check to ensure header was not saved in memory
     {
         LOCK(cs_main);
         BOOST_CHECK(m_node.chainman->m_blockman.LookupBlockIndex(
                         headerAB.GetHash()) == nullptr);
     }
 }
 
 BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/test/util/setup_common.cpp b/src/test/util/setup_common.cpp
index 1f2513370..d589e3544 100644
--- a/src/test/util/setup_common.cpp
+++ b/src/test/util/setup_common.cpp
@@ -1,626 +1,628 @@
 // Copyright (c) 2011-2019 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <test/util/setup_common.h>
 
 #include <kernel/mempool_entry.h>
 #include <kernel/validation_cache_sizes.h>
 
 #include <addrman.h>
 #include <banman.h>
 #include <chainparams.h>
 #include <config.h>
 #include <consensus/consensus.h>
 #include <consensus/merkle.h>
 #include <consensus/validation.h>
 #include <crypto/sha256.h>
 #include <init.h>
 #include <interfaces/chain.h>
 #include <logging.h>
 #include <mempool_args.h>
 #include <net.h>
 #include <net_processing.h>
 #include <node/blockstorage.h>
 #include <node/chainstate.h>
 #include <node/chainstatemanager_args.h>
 #include <node/context.h>
 #include <node/miner.h>
 #include <node/validation_cache_args.h>
 #include <noui.h>
 #include <pow/pow.h>
 #include <rpc/blockchain.h>
 #include <rpc/register.h>
 #include <rpc/server.h>
 #include <scheduler.h>
 #include <script/script_error.h>
 #include <script/scriptcache.h>
 #include <script/sigcache.h>
 #include <shutdown.h>
 #include <streams.h>
 #include <timedata.h>
 #include <txdb.h>
 #include <txmempool.h>
 #include <util/strencodings.h>
 #include <util/thread.h>
 #include <util/threadnames.h>
 #include <util/time.h>
 #include <util/translation.h>
 #include <util/vector.h>
 #include <validation.h>
 #include <validationinterface.h>
 #include <walletinitinterface.h>
 
 #include <test/util/mining.h>
 
 #include <algorithm>
 #include <functional>
 #include <memory>
 
 using kernel::ValidationCacheSizes;
 using node::ApplyArgsManOptions;
 using node::BlockAssembler;
 using node::CalculateCacheSizes;
 using node::fPruneMode;
 using node::fReindex;
 using node::LoadChainstate;
 using node::NodeContext;
 using node::VerifyLoadedChainstate;
 
 const std::function<std::string(const char *)> G_TRANSLATION_FUN = nullptr;
 
 FastRandomContext g_insecure_rand_ctx;
 /**
  * Random context to get unique temp data dirs. Separate from
  * g_insecure_rand_ctx, which can be seeded from a const env var
  */
 static FastRandomContext g_insecure_rand_ctx_temp_path;
 
 /**
  * Return the unsigned from the environment var if available,
  * otherwise 0
  */
 static uint256 GetUintFromEnv(const std::string &env_name) {
     const char *num = std::getenv(env_name.c_str());
     if (!num) {
         return {};
     }
     return uint256S(num);
 }
 
 void Seed(FastRandomContext &ctx) {
     // Should be enough to get the seed once for the process
     static uint256 seed{};
     static const std::string RANDOM_CTX_SEED{"RANDOM_CTX_SEED"};
     if (seed.IsNull()) {
         seed = GetUintFromEnv(RANDOM_CTX_SEED);
     }
     if (seed.IsNull()) {
         seed = GetRandHash();
     }
     LogPrintf("%s: Setting random seed for current tests to %s=%s\n", __func__,
               RANDOM_CTX_SEED, seed.GetHex());
     ctx = FastRandomContext(seed);
 }
 
 std::ostream &operator<<(std::ostream &os, const uint256 &num) {
     os << num.ToString();
     return os;
 }
 
 std::ostream &operator<<(std::ostream &os, const ScriptError &err) {
     os << ScriptErrorString(err);
     return os;
 }
 
 std::vector<const char *> fixture_extra_args{};
 
 BasicTestingSetup::BasicTestingSetup(
     const std::string &chainName, const std::vector<const char *> &extra_args)
     : m_path_root{fsbridge::GetTempDirectoryPath() /
                   "test_common_" PACKAGE_NAME /
                   g_insecure_rand_ctx_temp_path.rand256().ToString()},
       m_args{} {
     // clang-format off
     std::vector<const char *> arguments = Cat(
         {
             "dummy",
             "-printtoconsole=0",
             "-logsourcelocations",
             "-logtimemicros",
             "-debug",
             "-debugexclude=libevent",
             "-debugexclude=leveldb",
         },
         extra_args);
     // clang-format on
     arguments = Cat(arguments, fixture_extra_args);
     auto &config = const_cast<Config &>(GetConfig());
     SetMockTime(0);
     fs::create_directories(m_path_root);
     m_args.ForceSetArg("-datadir", fs::PathToString(m_path_root));
     gArgs.ForceSetArg("-datadir", fs::PathToString(m_path_root));
     gArgs.ClearPathCache();
     {
         SetupServerArgs(m_node);
         std::string error;
         const bool success{m_node.args->ParseParameters(
             arguments.size(), arguments.data(), error)};
         assert(success);
         assert(error.empty());
     }
     SelectParams(chainName);
     SeedInsecureRand();
     InitLogging(*m_node.args);
     AppInitParameterInteraction(config, *m_node.args);
     LogInstance().StartLogging();
     SHA256AutoDetect();
     ECC_Start();
     SetupEnvironment();
     SetupNetworking();
 
     ValidationCacheSizes validation_cache_sizes{};
     ApplyArgsManOptions(*m_node.args, validation_cache_sizes);
     Assert(InitSignatureCache(validation_cache_sizes.signature_cache_bytes));
     Assert(InitScriptExecutionCache(
         validation_cache_sizes.script_execution_cache_bytes));
 
     m_node.chain = interfaces::MakeChain(m_node, config.GetChainParams());
     g_wallet_init_interface.Construct(m_node);
 
     static bool noui_connected = false;
     if (!noui_connected) {
         noui_connect();
         noui_connected = true;
     }
 }
 
 BasicTestingSetup::~BasicTestingSetup() {
     LogInstance().DisconnectTestLogger();
     fs::remove_all(m_path_root);
     gArgs.ClearArgs();
     ECC_Stop();
 }
 CTxMemPool::Options MemPoolOptionsForTest(const NodeContext &node) {
     CTxMemPool::Options mempool_opts{
         // Default to always checking mempool regardless of
         // chainparams.DefaultConsistencyChecks for tests
         .check_ratio = 1,
     };
     const auto err{ApplyArgsManOptions(
         *node.args, ::GetConfig().GetChainParams(), mempool_opts)};
     Assert(!err);
     return mempool_opts;
 }
 
 ChainTestingSetup::ChainTestingSetup(
-    const std::string &chainName, const std::vector<const char *> &extra_args,
-    const Config &config)
+    const std::string &chainName, const std::vector<const char *> &extra_args)
     : BasicTestingSetup(chainName, extra_args) {
+    const Config &config = GetConfig();
+
     // We have to run a scheduler thread to prevent ActivateBestChain
     // from blocking due to queue overrun.
     m_node.scheduler = std::make_unique<CScheduler>();
     m_node.scheduler->m_service_thread =
         std::thread(util::TraceThread, "scheduler",
                     [&] { m_node.scheduler->serviceQueue(); });
     GetMainSignals().RegisterBackgroundSignalScheduler(*m_node.scheduler);
 
     m_node.mempool =
         std::make_unique<CTxMemPool>(MemPoolOptionsForTest(m_node));
 
     m_cache_sizes = CalculateCacheSizes(m_args);
 
     ChainstateManager::Options chainman_opts{
         .config = config,
         .adjusted_time_callback = GetAdjustedTime,
         .check_block_index = true,
     };
     ApplyArgsManOptions(*m_node.args, chainman_opts);
     m_node.chainman = std::make_unique<ChainstateManager>(chainman_opts);
     m_node.chainman->m_blockman.m_block_tree_db =
         std::make_unique<CBlockTreeDB>(m_cache_sizes.block_tree_db, true);
     // Call Upgrade on the block database so that the version field is set,
     // else LoadBlockIndexGuts will fail (see D8319).
     m_node.chainman->m_blockman.m_block_tree_db->Upgrade();
 
     constexpr int script_check_threads = 2;
     StartScriptCheckWorkerThreads(script_check_threads);
 }
 
 ChainTestingSetup::~ChainTestingSetup() {
     if (m_node.scheduler) {
         m_node.scheduler->stop();
     }
     StopScriptCheckWorkerThreads();
     GetMainSignals().FlushBackgroundCallbacks();
     GetMainSignals().UnregisterBackgroundSignalScheduler();
     m_node.connman.reset();
     m_node.banman.reset();
     m_node.addrman.reset();
     m_node.args = nullptr;
     m_node.mempool.reset();
     m_node.scheduler.reset();
     m_node.chainman.reset();
 }
 
 void TestingSetup::LoadVerifyActivateChainstate() {
     auto &chainman{*Assert(m_node.chainman)};
     node::ChainstateLoadOptions options;
     options.mempool = Assert(m_node.mempool.get());
     options.block_tree_db_in_memory = m_block_tree_db_in_memory;
     options.coins_db_in_memory = m_coins_db_in_memory;
     options.reindex = node::fReindex;
     options.reindex_chainstate =
         m_args.GetBoolArg("-reindex-chainstate", false);
     options.prune = chainman.m_blockman.IsPruneMode();
     options.check_blocks =
         m_args.GetIntArg("-checkblocks", DEFAULT_CHECKBLOCKS);
     options.check_level = m_args.GetIntArg("-checklevel", DEFAULT_CHECKLEVEL);
     options.require_full_verification =
         m_args.IsArgSet("-checkblocks") || m_args.IsArgSet("-checklevel");
     auto [status, error] = LoadChainstate(chainman, m_cache_sizes, options);
     assert(status == node::ChainstateLoadStatus::SUCCESS);
 
     std::tie(status, error) = VerifyLoadedChainstate(chainman, options);
     assert(status == node::ChainstateLoadStatus::SUCCESS);
 
     BlockValidationState state;
     if (!chainman.ActiveChainstate().ActivateBestChain(state)) {
         throw std::runtime_error(
             strprintf("ActivateBestChain failed. (%s)", state.ToString()));
     }
 }
 
 TestingSetup::TestingSetup(const std::string &chainName,
                            const std::vector<const char *> &extra_args,
                            const bool coins_db_in_memory,
-                           const bool block_tree_db_in_memory,
-                           const Config &config)
-    : ChainTestingSetup(chainName, extra_args, config),
+                           const bool block_tree_db_in_memory)
+    : ChainTestingSetup(chainName, extra_args),
       m_coins_db_in_memory(coins_db_in_memory),
       m_block_tree_db_in_memory(block_tree_db_in_memory) {
+    const Config &config = GetConfig();
+
     // Ideally we'd move all the RPC tests to the functional testing framework
     // instead of unit tests, but for now we need these here.
     RPCServer rpcServer;
     RegisterAllRPCCommands(config, rpcServer, tableRPC);
 
     /**
      * RPC does not come out of the warmup state on its own. Normally, this is
      * handled in bitcoind's init path, but unit tests do not trigger this
      * codepath, so we call it explicitly as part of setup.
      */
     std::string rpcWarmupStatus;
     if (RPCIsInWarmup(&rpcWarmupStatus)) {
         SetRPCWarmupFinished();
     }
 
     LoadVerifyActivateChainstate();
 
     m_node.addrman = std::make_unique<AddrMan>(
         /* asmap= */ std::vector<bool>(), /* consistency_check_ratio= */ 0);
     m_node.banman = std::make_unique<BanMan>(
         m_args.GetDataDirBase() / "banlist.dat", config.GetChainParams(),
         nullptr, DEFAULT_MISBEHAVING_BANTIME);
     // Deterministic randomness for tests.
     m_node.connman =
         std::make_unique<CConnman>(config, 0x1337, 0x1337, *m_node.addrman);
     m_node.peerman =
         PeerManager::make(*m_node.connman, *m_node.addrman, m_node.banman.get(),
                           *m_node.chainman, *m_node.mempool, false);
     {
         CConnman::Options options;
         options.m_msgproc.push_back(m_node.peerman.get());
         m_node.connman->Init(options);
     }
 }
 
 TestChain100Setup::TestChain100Setup(
     const std::string &chain_name, const std::vector<const char *> &extra_args,
     const bool coins_db_in_memory, const bool block_tree_db_in_memory)
     : TestingSetup{CBaseChainParams::REGTEST, extra_args, coins_db_in_memory,
                    block_tree_db_in_memory} {
     SetMockTime(1598887952);
     constexpr std::array<uint8_t, 32> vchKey = {
         {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
          0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}};
     coinbaseKey.Set(vchKey.begin(), vchKey.end(), true);
 
     // Generate a 100-block chain:
     this->mineBlocks(COINBASE_MATURITY);
 
     {
         LOCK(::cs_main);
         assert(
             m_node.chainman->ActiveTip()->GetBlockHash().ToString() ==
             "5afde277a26b6f36aee8f61a1dbf755587e1c6be63e654a88abe2a1ff0fbfb05");
     }
 }
 
 void TestChain100Setup::mineBlocks(int num_blocks) {
     CScript scriptPubKey = CScript() << ToByteVector(coinbaseKey.GetPubKey())
                                      << OP_CHECKSIG;
     for (int i = 0; i < num_blocks; i++) {
         std::vector<CMutableTransaction> noTxns;
         CBlock b = CreateAndProcessBlock(noTxns, scriptPubKey);
         SetMockTime(GetTime() + 1);
         m_coinbase_txns.push_back(b.vtx[0]);
     }
 }
 
 CBlock
 TestChain100Setup::CreateBlock(const std::vector<CMutableTransaction> &txns,
                                const CScript &scriptPubKey,
                                Chainstate &chainstate) {
     const Config &config = GetConfig();
     CBlock block = BlockAssembler{config, chainstate, nullptr}
                        .CreateNewBlock(scriptPubKey)
                        ->block;
 
     Assert(block.vtx.size() == 1);
     for (const CMutableTransaction &tx : txns) {
         block.vtx.push_back(MakeTransactionRef(tx));
     }
 
     // Order transactions by canonical order
     std::sort(std::begin(block.vtx) + 1, std::end(block.vtx),
               [](const std::shared_ptr<const CTransaction> &txa,
                  const std::shared_ptr<const CTransaction> &txb) -> bool {
                   return txa->GetId() < txb->GetId();
               });
 
     createCoinbaseAndMerkleRoot(&block,
                                 WITH_LOCK(m_node.chainman->GetMutex(),
                                           return m_node.chainman->ActiveTip()),
                                 config.GetMaxBlockSize());
 
     const Consensus::Params &params = config.GetChainParams().GetConsensus();
     while (!CheckProofOfWork(block.GetHash(), block.nBits, params)) {
         ++block.nNonce;
     }
 
     return block;
 }
 
 CBlock TestChain100Setup::CreateAndProcessBlock(
     const std::vector<CMutableTransaction> &txns, const CScript &scriptPubKey,
     Chainstate *chainstate) {
     if (!chainstate) {
         chainstate = &Assert(m_node.chainman)->ActiveChainstate();
     }
 
     const CBlock block = this->CreateBlock(txns, scriptPubKey, *chainstate);
     std::shared_ptr<const CBlock> shared_pblock =
         std::make_shared<const CBlock>(block);
     Assert(m_node.chainman)
         ->ProcessNewBlock(shared_pblock, true, true, nullptr);
 
     return block;
 }
 
 CMutableTransaction TestChain100Setup::CreateValidMempoolTransaction(
     CTransactionRef input_transaction, int input_vout, int input_height,
     CKey input_signing_key, CScript output_destination, Amount output_amount,
     bool submit) {
     // Transaction we will submit to the mempool
     CMutableTransaction mempool_txn;
 
     // Create an input
     COutPoint outpoint_to_spend(input_transaction->GetId(), input_vout);
     CTxIn input(outpoint_to_spend);
     mempool_txn.vin.push_back(input);
 
     // Create an output
     CTxOut output(output_amount, output_destination);
     mempool_txn.vout.push_back(output);
 
     // Sign the transaction
     // - Add the signing key to a keystore
     FillableSigningProvider keystore;
     keystore.AddKey(input_signing_key);
     // - Populate a CoinsViewCache with the unspent output
     CCoinsView coins_view;
     CCoinsViewCache coins_cache(&coins_view);
     AddCoins(coins_cache, *input_transaction.get(), input_height);
     // - Use GetCoin to properly populate utxo_to_spend,
     Coin utxo_to_spend;
     assert(coins_cache.GetCoin(outpoint_to_spend, utxo_to_spend));
     // - Then add it to a map to pass in to SignTransaction
     std::map<COutPoint, Coin> input_coins;
     input_coins.insert({outpoint_to_spend, utxo_to_spend});
     // - Default signature hashing type
     SigHashType nHashType = SigHashType().withForkId();
     std::map<int, std::string> input_errors;
     assert(SignTransaction(mempool_txn, &keystore, input_coins, nHashType,
                            input_errors));
 
     // If submit=true, add transaction to the mempool.
     if (submit) {
         LOCK(cs_main);
         const MempoolAcceptResult result = m_node.chainman->ProcessTransaction(
             MakeTransactionRef(mempool_txn));
         assert(result.m_result_type == MempoolAcceptResult::ResultType::VALID);
     }
 
     return mempool_txn;
 }
 
 TestChain100Setup::~TestChain100Setup() {
     SetMockTime(0);
 }
 
 std::vector<CTransactionRef>
 TestChain100Setup::PopulateMempool(FastRandomContext &det_rand,
                                    size_t num_transactions, bool submit) {
     std::vector<CTransactionRef> mempool_transactions;
     std::deque<std::pair<COutPoint, Amount>> unspent_prevouts;
     std::transform(m_coinbase_txns.begin(), m_coinbase_txns.end(),
                    std::back_inserter(unspent_prevouts), [](const auto &tx) {
                        return std::make_pair(COutPoint(tx->GetId(), 0),
                                              tx->vout[0].nValue);
                    });
     while (num_transactions > 0 && !unspent_prevouts.empty()) {
         // The number of inputs and outputs are random, between 1 and 24.
         CMutableTransaction mtx = CMutableTransaction();
         const size_t num_inputs = det_rand.randrange(24) + 1;
         Amount total_in{Amount::zero()};
         for (size_t n{0}; n < num_inputs; ++n) {
             if (unspent_prevouts.empty()) {
                 break;
             }
             const auto &[prevout, amount] = unspent_prevouts.front();
             mtx.vin.push_back(CTxIn(prevout, CScript()));
             total_in += amount;
             unspent_prevouts.pop_front();
         }
         const size_t num_outputs = det_rand.randrange(24) + 1;
         // Approximately 1000sat "fee," equal output amounts.
         const Amount amount_per_output =
             (total_in - 1000 * SATOSHI) / int(num_outputs);
         for (size_t n{0}; n < num_outputs; ++n) {
             CScript spk = CScript() << CScriptNum(num_transactions + n);
             mtx.vout.push_back(CTxOut(amount_per_output, spk));
         }
         CTransactionRef ptx = MakeTransactionRef(mtx);
         mempool_transactions.push_back(ptx);
         if (amount_per_output > 2000 * SATOSHI) {
             // If the value is high enough to fund another transaction + fees,
             // keep track of it so it can be used to build a more complex
             // transaction graph. Insert randomly into unspent_prevouts for
             // extra randomness in the resulting structures.
             for (size_t n{0}; n < num_outputs; ++n) {
                 unspent_prevouts.push_back(std::make_pair(
                     COutPoint(ptx->GetId(), n), amount_per_output));
                 std::swap(unspent_prevouts.back(),
                           unspent_prevouts[det_rand.randrange(
                               unspent_prevouts.size())]);
             }
         }
         if (submit) {
             LOCK2(m_node.mempool->cs, cs_main);
             LockPoints lp;
             m_node.mempool->addUnchecked(
                 CTxMemPoolEntryRef::make(ptx, 1000 * SATOSHI, 0, 1, 4, lp));
         }
         --num_transactions;
     }
     return mempool_transactions;
 }
 
 CTxMemPoolEntryRef
 TestMemPoolEntryHelper::FromTx(const CMutableTransaction &tx) const {
     return FromTx(MakeTransactionRef(tx));
 }
 
 CTxMemPoolEntryRef
 TestMemPoolEntryHelper::FromTx(const CTransactionRef &tx) const {
     CTxMemPoolEntry ret(tx, nFee, nTime, nHeight, nSigChecks, LockPoints());
     ret.SetEntryId(entryId);
     return CTxMemPoolEntryRef::make(std::move(ret));
 }
 
 /**
  * @returns a real block
  * (0000000000013b8ab2cd513b0261a14096412195a72a0c4827d229dcc7e0f7af) with 9
  * txs.
  */
 CBlock getBlock13b8a() {
     CBlock block;
     CDataStream stream(
         ParseHex(
             "0100000090f0a9f110702f808219ebea1173056042a714bad51b916cb680000000"
             "0000005275289558f51c9966699404ae2294730c3c9f9bda53523ce50e9b95e558"
             "da2fdb261b4d4c86041b1ab1bf9309010000000100000000000000000000000000"
             "00000000000000000000000000000000000000ffffffff07044c86041b0146ffff"
             "ffff0100f2052a01000000434104e18f7afbe4721580e81e8414fc8c24d7cfacf2"
             "54bb5c7b949450c3e997c2dc1242487a8169507b631eb3771f2b425483fb13102c"
             "4eb5d858eef260fe70fbfae0ac00000000010000000196608ccbafa16abada9027"
             "80da4dc35dafd7af05fa0da08cf833575f8cf9e836000000004a493046022100da"
             "b24889213caf43ae6adc41cf1c9396c08240c199f5225acf45416330fd7dbd0221"
             "00fe37900e0644bf574493a07fc5edba06dbc07c311b947520c2d514bc5725dcb4"
             "01ffffffff0100f2052a010000001976a914f15d1921f52e4007b146dfa60f369e"
             "d2fc393ce288ac000000000100000001fb766c1288458c2bafcfec81e48b24d98e"
             "c706de6b8af7c4e3c29419bfacb56d000000008c493046022100f268ba165ce0ad"
             "2e6d93f089cfcd3785de5c963bb5ea6b8c1b23f1ce3e517b9f022100da7c0f21ad"
             "c6c401887f2bfd1922f11d76159cbc597fbd756a23dcbb00f4d7290141042b4e86"
             "25a96127826915a5b109852636ad0da753c9e1d5606a50480cd0c40f1f8b8d8982"
             "35e571fe9357d9ec842bc4bba1827daaf4de06d71844d0057707966affffffff02"
             "80969800000000001976a9146963907531db72d0ed1a0cfb471ccb63923446f388"
             "ac80d6e34c000000001976a914f0688ba1c0d1ce182c7af6741e02658c7d4dfcd3"
             "88ac000000000100000002c40297f730dd7b5a99567eb8d27b78758f607507c522"
             "92d02d4031895b52f2ff010000008b483045022100f7edfd4b0aac404e5bab4fd3"
             "889e0c6c41aa8d0e6fa122316f68eddd0a65013902205b09cc8b2d56e1cd1f7f2f"
             "afd60a129ed94504c4ac7bdc67b56fe67512658b3e014104732012cb962afa90d3"
             "1b25d8fb0e32c94e513ab7a17805c14ca4c3423e18b4fb5d0e676841733cb83aba"
             "f975845c9f6f2a8097b7d04f4908b18368d6fc2d68ecffffffffca5065ff9617cb"
             "cba45eb23726df6498a9b9cafed4f54cbab9d227b0035ddefb000000008a473044"
             "022068010362a13c7f9919fa832b2dee4e788f61f6f5d344a7c2a0da6ae7406056"
             "58022006d1af525b9a14a35c003b78b72bd59738cd676f845d1ff3fc25049e0100"
             "3614014104732012cb962afa90d31b25d8fb0e32c94e513ab7a17805c14ca4c342"
             "3e18b4fb5d0e676841733cb83abaf975845c9f6f2a8097b7d04f4908b18368d6fc"
             "2d68ecffffffff01001ec4110200000043410469ab4181eceb28985b9b4e895c13"
             "fa5e68d85761b7eee311db5addef76fa8621865134a221bd01f28ec9999ee3e021"
             "e60766e9d1f3458c115fb28650605f11c9ac000000000100000001cdaf2f758e91"
             "c514655e2dc50633d1e4c84989f8aa90a0dbc883f0d23ed5c2fa010000008b4830"
             "4502207ab51be6f12a1962ba0aaaf24a20e0b69b27a94fac5adf45aa7d2d18ffd9"
             "236102210086ae728b370e5329eead9accd880d0cb070aea0c96255fae6c4f1ddc"
             "ce1fd56e014104462e76fd4067b3a0aa42070082dcb0bf2f388b6495cf33d78990"
             "4f07d0f55c40fbd4b82963c69b3dc31895d0c772c812b1d5fbcade15312ef1c0e8"
             "ebbb12dcd4ffffffff02404b4c00000000001976a9142b6ba7c9d796b75eef7942"
             "fc9288edd37c32f5c388ac002d3101000000001976a9141befba0cdc1ad5652937"
             "1864d9f6cb042faa06b588ac000000000100000001b4a47603e71b61bc3326efd9"
             "0111bf02d2f549b067f4c4a8fa183b57a0f800cb010000008a4730440220177c37"
             "f9a505c3f1a1f0ce2da777c339bd8339ffa02c7cb41f0a5804f473c9230220585b"
             "25a2ee80eb59292e52b987dad92acb0c64eced92ed9ee105ad153cdb12d0014104"
             "43bd44f683467e549dae7d20d1d79cbdb6df985c6e9c029c8d0c6cb46cc1a4d3cf"
             "7923c5021b27f7a0b562ada113bc85d5fda5a1b41e87fe6e8802817cf69996ffff"
             "ffff0280651406000000001976a9145505614859643ab7b547cd7f1f5e7e2a1232"
             "2d3788ac00aa0271000000001976a914ea4720a7a52fc166c55ff2298e07baf70a"
             "e67e1b88ac00000000010000000586c62cd602d219bb60edb14a3e204de0705176"
             "f9022fe49a538054fb14abb49e010000008c493046022100f2bc2aba2534becbdf"
             "062eb993853a42bbbc282083d0daf9b4b585bd401aa8c9022100b1d7fd7ee0b956"
             "00db8535bbf331b19eed8d961f7a8e54159c53675d5f69df8c014104462e76fd40"
             "67b3a0aa42070082dcb0bf2f388b6495cf33d789904f07d0f55c40fbd4b82963c6"
             "9b3dc31895d0c772c812b1d5fbcade15312ef1c0e8ebbb12dcd4ffffffff03ad0e"
             "58ccdac3df9dc28a218bcf6f1997b0a93306faaa4b3a28ae83447b217901000000"
             "8b483045022100be12b2937179da88599e27bb31c3525097a07cdb52422d165b3c"
             "a2f2020ffcf702200971b51f853a53d644ebae9ec8f3512e442b1bcb6c315a5b49"
             "1d119d10624c83014104462e76fd4067b3a0aa42070082dcb0bf2f388b6495cf33"
             "d789904f07d0f55c40fbd4b82963c69b3dc31895d0c772c812b1d5fbcade15312e"
             "f1c0e8ebbb12dcd4ffffffff2acfcab629bbc8685792603762c921580030ba144a"
             "f553d271716a95089e107b010000008b483045022100fa579a840ac258871365dd"
             "48cd7552f96c8eea69bd00d84f05b283a0dab311e102207e3c0ee9234814cfbb1b"
             "659b83671618f45abc1326b9edcc77d552a4f2a805c0014104462e76fd4067b3a0"
             "aa42070082dcb0bf2f388b6495cf33d789904f07d0f55c40fbd4b82963c69b3dc3"
             "1895d0c772c812b1d5fbcade15312ef1c0e8ebbb12dcd4ffffffffdcdc6023bbc9"
             "944a658ddc588e61eacb737ddf0a3cd24f113b5a8634c517fcd2000000008b4830"
             "450221008d6df731df5d32267954bd7d2dda2302b74c6c2a6aa5c0ca64ecbabc1a"
             "f03c75022010e55c571d65da7701ae2da1956c442df81bbf076cdbac25133f99d9"
             "8a9ed34c014104462e76fd4067b3a0aa42070082dcb0bf2f388b6495cf33d78990"
             "4f07d0f55c40fbd4b82963c69b3dc31895d0c772c812b1d5fbcade15312ef1c0e8"
             "ebbb12dcd4ffffffffe15557cd5ce258f479dfd6dc6514edf6d7ed5b21fcfa4a03"
             "8fd69f06b83ac76e010000008b483045022023b3e0ab071eb11de2eb1cc3a67261"
             "b866f86bf6867d4558165f7c8c8aca2d86022100dc6e1f53a91de3efe8f6351285"
             "0811f26284b62f850c70ca73ed5de8771fb451014104462e76fd4067b3a0aa4207"
             "0082dcb0bf2f388b6495cf33d789904f07d0f55c40fbd4b82963c69b3dc31895d0"
             "c772c812b1d5fbcade15312ef1c0e8ebbb12dcd4ffffffff01404b4c0000000000"
             "1976a9142b6ba7c9d796b75eef7942fc9288edd37c32f5c388ac00000000010000"
             "000166d7577163c932b4f9690ca6a80b6e4eb001f0a2fa9023df5595602aae96ed"
             "8d000000008a4730440220262b42546302dfb654a229cefc86432b89628ff259dc"
             "87edd1154535b16a67e102207b4634c020a97c3e7bbd0d4d19da6aa2269ad9dded"
             "4026e896b213d73ca4b63f014104979b82d02226b3a4597523845754d44f13639e"
             "3bf2df5e82c6aab2bdc79687368b01b1ab8b19875ae3c90d661a3d0a33161dab29"
             "934edeb36aa01976be3baf8affffffff02404b4c00000000001976a9144854e695"
             "a02af0aeacb823ccbc272134561e0a1688ac40420f00000000001976a914abee93"
             "376d6b37b5c2940655a6fcaf1c8e74237988ac0000000001000000014e3f8ef2e9"
             "1349a9059cb4f01e54ab2597c1387161d3da89919f7ea6acdbb371010000008c49"
             "304602210081f3183471a5ca22307c0800226f3ef9c353069e0773ac76bb580654"
             "d56aa523022100d4c56465bdc069060846f4fbf2f6b20520b2a80b08b168b31e66"
             "ddb9c694e240014104976c79848e18251612f8940875b2b08d06e6dc73b9840e88"
             "60c066b7e87432c477e9a59a453e71e6d76d5fe34058b800a098fc1740ce3012e8"
             "fc8a00c96af966ffffffff02c0e1e400000000001976a9144134e75a6fcb604203"
             "4aab5e18570cf1f844f54788ac404b4c00000000001976a9142b6ba7c9d796b75e"
             "ef7942fc9288edd37c32f5c388ac00000000"),
         SER_NETWORK, PROTOCOL_VERSION);
     stream >> block;
     return block;
 }
diff --git a/src/test/util/setup_common.h b/src/test/util/setup_common.h
index 80a7b2a24..504d99408 100644
--- a/src/test/util/setup_common.h
+++ b/src/test/util/setup_common.h
@@ -1,305 +1,303 @@
 // Copyright (c) 2015-2019 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_TEST_UTIL_SETUP_COMMON_H
 #define BITCOIN_TEST_UTIL_SETUP_COMMON_H
 
 #include <blockindex.h>
 #include <chainparamsbase.h>
 #include <config.h>
 #include <consensus/amount.h>
 #include <fs.h>
 #include <key.h>
 #include <node/caches.h>
 #include <node/context.h>
 #include <primitives/transaction.h>
 #include <pubkey.h>
 #include <random.h>
 #include <stdexcept>
 #include <txmempool.h>
 #include <util/check.h>
 #include <util/string.h>
 #include <util/system.h>
 #include <util/vector.h>
 
 #include <type_traits>
 #include <vector>
 
 class Config;
 
 // Enable BOOST_CHECK_EQUAL for enum class types
 template <typename T>
 std::ostream &operator<<(
     typename std::enable_if<std::is_enum<T>::value, std::ostream>::type &stream,
     const T &e) {
     return stream << static_cast<typename std::underlying_type<T>::type>(e);
 }
 
 /**
  * This global and the helpers that use it are not thread-safe.
  *
  * If thread-safety is needed, the global could be made thread_local (given
  * that thread_local is supported on all architectures we support) or a
  * per-thread instance could be used in the multi-threaded test.
  */
 extern FastRandomContext g_insecure_rand_ctx;
 
 /**
  * Flag to make GetRand in random.h return the same number
  */
 extern bool g_mock_deterministic_tests;
 
 enum class SeedRand {
     ZEROS, //!< Seed with a compile time constant of zeros
     SEED,  //!< Call the Seed() helper
 };
 
 /**
  * Seed the given random ctx or use the seed passed in via an
  * environment var
  */
 void Seed(FastRandomContext &ctx);
 
 static inline void SeedInsecureRand(SeedRand seed = SeedRand::SEED) {
     if (seed == SeedRand::ZEROS) {
         g_insecure_rand_ctx = FastRandomContext(/* deterministic */ true);
     } else {
         Seed(g_insecure_rand_ctx);
     }
 }
 
 static inline uint32_t InsecureRand32() {
     return g_insecure_rand_ctx.rand32();
 }
 static inline uint160 InsecureRand160() {
     return g_insecure_rand_ctx.rand160();
 }
 static inline uint256 InsecureRand256() {
     return g_insecure_rand_ctx.rand256();
 }
 static inline uint64_t InsecureRandBits(int bits) {
     return g_insecure_rand_ctx.randbits(bits);
 }
 static inline uint64_t InsecureRandRange(uint64_t range) {
     return g_insecure_rand_ctx.randrange(range);
 }
 static inline bool InsecureRandBool() {
     return g_insecure_rand_ctx.randbool();
 }
 
 static constexpr Amount CENT(COIN / 100);
 
 extern std::vector<const char *> fixture_extra_args;
 
 /**
  * Basic testing setup.
  * This just configures logging, data dir and chain parameters.
  */
 struct BasicTestingSetup {
     ECCVerifyHandle globalVerifyHandle;
     node::NodeContext m_node;
 
     explicit BasicTestingSetup(
         const std::string &chainName = CBaseChainParams::MAIN,
         const std::vector<const char *> &extra_args = {});
     ~BasicTestingSetup();
 
     const fs::path m_path_root;
     ArgsManager m_args;
 };
 
 CTxMemPool::Options MemPoolOptionsForTest(const node::NodeContext &node);
 
 /**
  * Testing setup that performs all steps up until right before
  * ChainstateManager gets initialized. Meant for testing ChainstateManager
  * initialization behaviour.
  */
 struct ChainTestingSetup : public BasicTestingSetup {
     node::CacheSizes m_cache_sizes{};
 
     explicit ChainTestingSetup(
         const std::string &chainName = CBaseChainParams::MAIN,
-        const std::vector<const char *> &extra_args = {},
-        const Config &config = ::GetConfig());
+        const std::vector<const char *> &extra_args = {});
     ~ChainTestingSetup();
 };
 
 /**
  * Testing setup that configures a complete environment.
  */
 struct TestingSetup : public ChainTestingSetup {
     bool m_coins_db_in_memory{true};
     bool m_block_tree_db_in_memory{true};
 
     void LoadVerifyActivateChainstate();
 
     explicit TestingSetup(const std::string &chainName = CBaseChainParams::MAIN,
                           const std::vector<const char *> &extra_args = {},
                           const bool coins_db_in_memory = true,
-                          const bool block_tree_db_in_memory = true,
-                          const Config &config = ::GetConfig());
+                          const bool block_tree_db_in_memory = true);
 };
 
 /** Identical to TestingSetup, but chain set to regtest */
 struct RegTestingSetup : public TestingSetup {
     RegTestingSetup() : TestingSetup{CBaseChainParams::REGTEST} {}
 };
 
 class CBlock;
 class Chainstate;
 class CMutableTransaction;
 class CScript;
 
 /**
  * Testing fixture that pre-creates a 100-block REGTEST-mode block chain
  */
 struct TestChain100Setup : public TestingSetup {
     TestChain100Setup(const std::string &chain_name = CBaseChainParams::REGTEST,
                       const std::vector<const char *> &extra_args = {},
                       const bool coins_db_in_memory = true,
                       const bool block_tree_db_in_memory = true);
 
     /**
      * Create a new block with just given transactions, coinbase paying to
      * scriptPubKey, and try to add it to the current chain.
      * If no chainstate is specified, default to the active.
      */
     CBlock CreateAndProcessBlock(const std::vector<CMutableTransaction> &txns,
                                  const CScript &scriptPubKey,
                                  Chainstate *chainstate = nullptr);
 
     /**
      * Create a new block with just given transactions, coinbase paying to
      * scriptPubKey.
      */
     CBlock CreateBlock(const std::vector<CMutableTransaction> &txns,
                        const CScript &scriptPubKey, Chainstate &chainstate);
 
     //! Mine a series of new blocks on the active chain.
     void mineBlocks(int num_blocks);
 
     /**
      * Create a transaction and submit to the mempool.
      *
      * @param input_transaction  The transaction to spend
      * @param input_vout         The vout to spend from the input_transaction
      * @param input_height       The height of the block that included the
      *                           input_transaction
      * @param input_signing_key  The key to spend the input_transaction
      * @param output_destination Where to send the output
      * @param output_amount      How much to send
      * @param submit             Whether or not to submit to mempool
      */
     CMutableTransaction CreateValidMempoolTransaction(
         CTransactionRef input_transaction, int input_vout, int input_height,
         CKey input_signing_key, CScript output_destination,
         Amount output_amount = COIN, bool submit = true);
 
     ~TestChain100Setup();
 
     /**
      * Create transactions spending from m_coinbase_txns. These transactions
      * will only spend coins that exist in the current chain, but may be
      * premature coinbase spends, have missing signatures, or violate some other
      * consensus rules. They should only be used for testing mempool
      * consistency. All transactions will have some random number of inputs and
      * outputs (between 1 and 24). Transactions may or may not be dependent upon
      * each other; if dependencies exit, every parent will always be somewhere
      * in the list before the child so each transaction can be submitted in the
      * same order they appear in the list.
      * @param[in]   submit      When true, submit transactions to the mempool.
      *                          When false, return them but don't submit them.
      * @returns A vector of transactions that can be submitted to the mempool.
      */
     std::vector<CTransactionRef> PopulateMempool(FastRandomContext &det_rand,
                                                  size_t num_transactions,
                                                  bool submit);
 
     // For convenience, coinbase transactions.
     std::vector<CTransactionRef> m_coinbase_txns;
     // private/public key needed to spend coinbase transactions.
     CKey coinbaseKey;
 };
 
 /**
  * Make a test setup that has disk access to the debug.log file disabled. Can
  * be used in "hot loops", for example fuzzing or benchmarking.
  */
 template <class T = const BasicTestingSetup>
 std::unique_ptr<T>
 MakeNoLogFileContext(const std::string &chain_name = CBaseChainParams::REGTEST,
                      const std::vector<const char *> &extra_args = {}) {
     const std::vector<const char *> arguments = Cat(
         {
             "-nodebuglogfile",
             "-nodebug",
         },
         extra_args);
 
     return std::make_unique<T>(chain_name, arguments);
 }
 
 struct TestMemPoolEntryHelper {
     // Default values
     Amount nFee;
     int64_t nTime;
     unsigned int nHeight;
     unsigned int nSigChecks;
     uint64_t entryId = 0;
 
     TestMemPoolEntryHelper() : nFee(), nTime(0), nHeight(1), nSigChecks(1) {}
 
     CTxMemPoolEntryRef FromTx(const CMutableTransaction &tx) const;
     CTxMemPoolEntryRef FromTx(const CTransactionRef &tx) const;
 
     // Change the default value
     TestMemPoolEntryHelper &Fee(Amount _fee) {
         nFee = _fee;
         return *this;
     }
     TestMemPoolEntryHelper &Time(int64_t _time) {
         nTime = _time;
         return *this;
     }
     TestMemPoolEntryHelper &Height(unsigned int _height) {
         nHeight = _height;
         return *this;
     }
     TestMemPoolEntryHelper &SigChecks(unsigned int _nSigChecks) {
         nSigChecks = _nSigChecks;
         return *this;
     }
     TestMemPoolEntryHelper &EntryId(uint64_t _entryId) {
         entryId = _entryId;
         return *this;
     }
 };
 
 enum class ScriptError;
 
 // define implicit conversions here so that these types may be used in
 // BOOST_*_EQUAL
 std::ostream &operator<<(std::ostream &os, const uint256 &num);
 std::ostream &operator<<(std::ostream &os, const ScriptError &err);
 
 CBlock getBlock13b8a();
 
 /**
  * BOOST_CHECK_EXCEPTION predicates to check the specific validation error.
  * Use as
  * BOOST_CHECK_EXCEPTION(code that throws, exception type, HasReason("foo"));
  */
 class HasReason {
 public:
     explicit HasReason(const std::string &reason) : m_reason(reason) {}
     bool operator()(const std::exception &e) const {
         return std::string(e.what()).find(m_reason) != std::string::npos;
     };
 
 private:
     const std::string m_reason;
 };
 
 #endif // BITCOIN_TEST_UTIL_SETUP_COMMON_H
diff --git a/src/validation.cpp b/src/validation.cpp
index ece734da0..bcd2d21c7 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -1,6561 +1,6562 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2018 The Bitcoin Core developers
 // Copyright (c) 2017-2020 The Bitcoin developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <validation.h>
 
 #include <kernel/disconnected_transactions.h>
 #include <kernel/mempool_entry.h>
 #include <kernel/mempool_persist.h>
 
 #include <arith_uint256.h>
 #include <avalanche/avalanche.h>
 #include <avalanche/processor.h>
 #include <blockvalidity.h>
 #include <chainparams.h>
 #include <checkpoints.h>
 #include <checkqueue.h>
 #include <config.h>
 #include <consensus/activation.h>
 #include <consensus/amount.h>
 #include <consensus/merkle.h>
 #include <consensus/tx_check.h>
 #include <consensus/tx_verify.h>
 #include <consensus/validation.h>
 #include <fs.h>
 #include <hash.h>
 #include <index/blockfilterindex.h>
 #include <logging.h>
 #include <logging/timer.h>
 #include <minerfund.h>
 #include <node/blockstorage.h>
 #include <node/coinstats.h>
 #include <node/ui_interface.h>
 #include <node/utxo_snapshot.h>
 #include <policy/block/minerfund.h>
 #include <policy/block/preconsensus.h>
 #include <policy/block/stakingrewards.h>
 #include <policy/policy.h>
 #include <policy/settings.h>
 #include <pow/pow.h>
 #include <primitives/block.h>
 #include <primitives/transaction.h>
 #include <random.h>
 #include <reverse_iterator.h>
 #include <script/script.h>
 #include <script/scriptcache.h>
 #include <script/sigcache.h>
 #include <shutdown.h>
 #include <tinyformat.h>
 #include <txdb.h>
 #include <txmempool.h>
 #include <undo.h>
 #include <util/check.h> // For NDEBUG compile time check
 #include <util/strencodings.h>
 #include <util/string.h>
 #include <util/system.h>
 #include <util/time.h>
 #include <util/trace.h>
 #include <util/translation.h>
 #include <validationinterface.h>
 #include <warnings.h>
 
 #include <algorithm>
 #include <atomic>
 #include <cassert>
 #include <chrono>
 #include <deque>
 #include <numeric>
 #include <optional>
 #include <string>
 #include <thread>
 
 using kernel::LoadMempool;
 
 using fsbridge::FopenFn;
 using node::BLOCKFILE_CHUNK_SIZE;
 using node::BlockManager;
 using node::BlockMap;
 using node::CCoinsStats;
 using node::CoinStatsHashType;
 using node::ComputeUTXOStats;
 using node::fReindex;
 using node::nPruneTarget;
 using node::OpenBlockFile;
 using node::ReadBlockFromDisk;
 using node::SnapshotMetadata;
 using node::UNDOFILE_CHUNK_SIZE;
 using node::UndoReadFromDisk;
 using node::UnlinkPrunedFiles;
 
 #define MICRO 0.000001
 #define MILLI 0.001
 
 /** Time to wait between writing blocks/block index to disk. */
 static constexpr std::chrono::hours DATABASE_WRITE_INTERVAL{1};
 /** Time to wait between flushing chainstate to disk. */
 static constexpr std::chrono::hours DATABASE_FLUSH_INTERVAL{24};
 const std::vector<std::string> CHECKLEVEL_DOC{
     "level 0 reads the blocks from disk",
     "level 1 verifies block validity",
     "level 2 verifies undo data",
     "level 3 checks disconnection of tip blocks",
     "level 4 tries to reconnect the blocks",
     "each level includes the checks of the previous levels",
 };
 
 GlobalMutex g_best_block_mutex;
 std::condition_variable g_best_block_cv;
 uint256 g_best_block;
 
 BlockValidationOptions::BlockValidationOptions(const Config &config)
     : excessiveBlockSize(config.GetMaxBlockSize()), checkPoW(true),
       checkMerkleRoot(true) {}
 
 const CBlockIndex *
 Chainstate::FindForkInGlobalIndex(const CBlockLocator &locator) const {
     AssertLockHeld(cs_main);
 
     // Find the latest block common to locator and chain - we expect that
     // locator.vHave is sorted descending by height.
     for (const BlockHash &hash : locator.vHave) {
         const CBlockIndex *pindex{m_blockman.LookupBlockIndex(hash)};
         if (pindex) {
             if (m_chain.Contains(pindex)) {
                 return pindex;
             }
             if (pindex->GetAncestor(m_chain.Height()) == m_chain.Tip()) {
                 return m_chain.Tip();
             }
         }
     }
     return m_chain.Genesis();
 }
 
 static uint32_t GetNextBlockScriptFlags(const CBlockIndex *pindex,
                                         const ChainstateManager &chainman);
 
 bool CheckSequenceLocksAtTip(CBlockIndex *tip, const CCoinsView &coins_view,
                              const CTransaction &tx, LockPoints *lp,
                              bool useExistingLockPoints) {
     assert(tip != nullptr);
 
     CBlockIndex index;
     index.pprev = tip;
     // CheckSequenceLocksAtTip() uses active_chainstate.m_chain.Height()+1 to
     // evaluate height based locks because when SequenceLocks() is called within
     // ConnectBlock(), the height of the block *being* evaluated is what is
     // used. Thus if we want to know if a transaction can be part of the *next*
     // block, we need to use one more than active_chainstate.m_chain.Height()
     index.nHeight = tip->nHeight + 1;
 
     std::pair<int, int64_t> lockPair;
     if (useExistingLockPoints) {
         assert(lp);
         lockPair.first = lp->height;
         lockPair.second = lp->time;
     } else {
         std::vector<int> prevheights;
         prevheights.resize(tx.vin.size());
         for (size_t txinIndex = 0; txinIndex < tx.vin.size(); txinIndex++) {
             const CTxIn &txin = tx.vin[txinIndex];
             Coin coin;
             if (!coins_view.GetCoin(txin.prevout, coin)) {
                 return error("%s: Missing input", __func__);
             }
             if (coin.GetHeight() == MEMPOOL_HEIGHT) {
                 // Assume all mempool transaction confirm in the next block
                 prevheights[txinIndex] = tip->nHeight + 1;
             } else {
                 prevheights[txinIndex] = coin.GetHeight();
             }
         }
         lockPair = CalculateSequenceLocks(tx, STANDARD_LOCKTIME_VERIFY_FLAGS,
                                           prevheights, index);
         if (lp) {
             lp->height = lockPair.first;
             lp->time = lockPair.second;
         }
     }
     return EvaluateSequenceLocks(index, lockPair);
 }
 
 // Command-line argument "-replayprotectionactivationtime=<timestamp>" will
 // cause the node to switch to replay protected SigHash ForkID value when the
 // median timestamp of the previous 11 blocks is greater than or equal to
 // <timestamp>. Defaults to the pre-defined timestamp when not set.
 static bool IsReplayProtectionEnabled(const Consensus::Params &params,
                                       int64_t nMedianTimePast) {
     return nMedianTimePast >= gArgs.GetIntArg("-replayprotectionactivationtime",
                                               params.leeKuanYewActivationTime);
 }
 
 static bool IsReplayProtectionEnabled(const Consensus::Params &params,
                                       const CBlockIndex *pindexPrev) {
     if (pindexPrev == nullptr) {
         return false;
     }
 
     return IsReplayProtectionEnabled(params, pindexPrev->GetMedianTimePast());
 }
 
 /**
  * Checks to avoid mempool polluting consensus critical paths since cached
  * signature and script validity results will be reused if we validate this
  * transaction again during block validation.
  */
 static bool CheckInputsFromMempoolAndCache(
     const CTransaction &tx, TxValidationState &state,
     const CCoinsViewCache &view, const CTxMemPool &pool, const uint32_t flags,
     PrecomputedTransactionData &txdata, int &nSigChecksOut,
     CCoinsViewCache &coins_tip) EXCLUSIVE_LOCKS_REQUIRED(cs_main, pool.cs) {
     AssertLockHeld(cs_main);
     AssertLockHeld(pool.cs);
 
     assert(!tx.IsCoinBase());
     for (const CTxIn &txin : tx.vin) {
         const Coin &coin = view.AccessCoin(txin.prevout);
 
         // This coin was checked in PreChecks and MemPoolAccept
         // has been holding cs_main since then.
         Assume(!coin.IsSpent());
         if (coin.IsSpent()) {
             return false;
         }
 
         // If the Coin is available, there are 2 possibilities:
         // it is available in our current ChainstateActive UTXO set,
         // or it's a UTXO provided by a transaction in our mempool.
         // Ensure the scriptPubKeys in Coins from CoinsView are correct.
         const CTransactionRef &txFrom = pool.get(txin.prevout.GetTxId());
         if (txFrom) {
             assert(txFrom->GetId() == txin.prevout.GetTxId());
             assert(txFrom->vout.size() > txin.prevout.GetN());
             assert(txFrom->vout[txin.prevout.GetN()] == coin.GetTxOut());
         } else {
             const Coin &coinFromUTXOSet = coins_tip.AccessCoin(txin.prevout);
             assert(!coinFromUTXOSet.IsSpent());
             assert(coinFromUTXOSet.GetTxOut() == coin.GetTxOut());
         }
     }
 
     // Call CheckInputScripts() to cache signature and script validity against
     // current tip consensus rules.
     return CheckInputScripts(tx, state, view, flags, /*sigCacheStore=*/true,
                              /*scriptCacheStore=*/true, txdata, nSigChecksOut);
 }
 
 namespace {
 
 class MemPoolAccept {
 public:
     MemPoolAccept(CTxMemPool &mempool, Chainstate &active_chainstate)
         : m_pool(mempool), m_view(&m_dummy),
           m_viewmempool(&active_chainstate.CoinsTip(), m_pool),
           m_active_chainstate(active_chainstate) {}
 
     // We put the arguments we're handed into a struct, so we can pass them
     // around easier.
     struct ATMPArgs {
         const Config &m_config;
         const int64_t m_accept_time;
         const bool m_bypass_limits;
         /*
          * Return any outpoints which were not previously present in the coins
          * cache, but were added as a result of validating the tx for mempool
          * acceptance. This allows the caller to optionally remove the cache
          * additions if the associated transaction ends up being rejected by
          * the mempool.
          */
         std::vector<COutPoint> &m_coins_to_uncache;
         const bool m_test_accept;
         const unsigned int m_heightOverride;
         /**
          * When true, the mempool will not be trimmed when individual
          * transactions are submitted in Finalize(). Instead, limits should be
          * enforced at the end to ensure the package is not partially submitted.
          */
         const bool m_package_submission;
 
         /** Parameters for single transaction mempool validation. */
         static ATMPArgs SingleAccept(const Config &config, int64_t accept_time,
                                      bool bypass_limits,
                                      std::vector<COutPoint> &coins_to_uncache,
                                      bool test_accept,
                                      unsigned int heightOverride) {
             return ATMPArgs{config,
                             accept_time,
                             bypass_limits,
                             coins_to_uncache,
                             test_accept,
                             heightOverride,
                             /*package_submission=*/false};
         }
 
         /**
          * Parameters for test package mempool validation through
          * testmempoolaccept.
          */
         static ATMPArgs
         PackageTestAccept(const Config &config, int64_t accept_time,
                           std::vector<COutPoint> &coins_to_uncache) {
             return ATMPArgs{config, accept_time,
                             /*bypass_limits=*/false, coins_to_uncache,
                             /*test_accept=*/true,
                             /*height_override=*/0,
                             // not submitting to mempool
                             /*package_submission=*/false};
         }
 
         /** Parameters for child-with-unconfirmed-parents package validation. */
         static ATMPArgs
         PackageChildWithParents(const Config &config, int64_t accept_time,
                                 std::vector<COutPoint> &coins_to_uncache) {
             return ATMPArgs{config,
                             accept_time,
                             /*bypass_limits=*/false,
                             coins_to_uncache,
                             /*test_accept=*/false,
                             /*height_override=*/0,
                             /*package_submission=*/true};
         }
 
     private:
         // Private ctor to avoid exposing details to clients and allowing the
         // possibility of mixing up the order of the arguments. Use static
         // functions above instead.
         ATMPArgs(const Config &config, int64_t accept_time, bool bypass_limits,
                  std::vector<COutPoint> &coins_to_uncache, bool test_accept,
                  unsigned int height_override, bool package_submission)
             : m_config{config}, m_accept_time{accept_time},
               m_bypass_limits{bypass_limits},
               m_coins_to_uncache{coins_to_uncache}, m_test_accept{test_accept},
               m_heightOverride{height_override}, m_package_submission{
                                                      package_submission} {}
     };
 
     // Single transaction acceptance
     MempoolAcceptResult AcceptSingleTransaction(const CTransactionRef &ptx,
                                                 ATMPArgs &args)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     /**
      * Multiple transaction acceptance. Transactions may or may not be
      * interdependent, but must not conflict with each other, and the
      * transactions cannot already be in the mempool. Parents must come
      * before children if any dependencies exist.
      */
     PackageMempoolAcceptResult
     AcceptMultipleTransactions(const std::vector<CTransactionRef> &txns,
                                ATMPArgs &args)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     /**
      * Package (more specific than just multiple transactions) acceptance.
      * Package must be a child with all of its unconfirmed parents, and
      * topologically sorted.
      */
     PackageMempoolAcceptResult AcceptPackage(const Package &package,
                                              ATMPArgs &args)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
 private:
     // All the intermediate state that gets passed between the various levels
     // of checking a given transaction.
     struct Workspace {
         Workspace(const CTransactionRef &ptx,
                   const uint32_t next_block_script_verify_flags)
             : m_ptx(ptx),
               m_next_block_script_verify_flags(next_block_script_verify_flags) {
         }
         /**
          * Mempool entry constructed for this transaction.
          * Constructed in PreChecks() but not inserted into the mempool until
          * Finalize().
          */
         std::unique_ptr<CTxMemPoolEntry> m_entry;
 
         /**
          * Virtual size of the transaction as used by the mempool, calculated
          * using serialized size of the transaction and sigchecks.
          */
         int64_t m_vsize;
         /**
          * Fees paid by this transaction: total input amounts subtracted by
          * total output amounts.
          */
         Amount m_base_fees;
 
         /**
          * Base fees + any fee delta set by the user with
          * prioritisetransaction.
          */
         Amount m_modified_fees;
 
         const CTransactionRef &m_ptx;
         TxValidationState m_state;
         /**
          * A temporary cache containing serialized transaction data for
          * signature verification.
          * Reused across PreChecks and ConsensusScriptChecks.
          */
         PrecomputedTransactionData m_precomputed_txdata;
 
         // ABC specific flags that are used in both PreChecks and
         // ConsensusScriptChecks
         const uint32_t m_next_block_script_verify_flags;
         int m_sig_checks_standard;
     };
 
     // Run the policy checks on a given transaction, excluding any script
     // checks. Looks up inputs, calculates feerate, considers replacement,
     // evaluates package limits, etc. As this function can be invoked for "free"
     // by a peer, only tests that are fast should be done here (to avoid CPU
     // DoS).
     bool PreChecks(ATMPArgs &args, Workspace &ws)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
 
     // Re-run the script checks, using consensus flags, and try to cache the
     // result in the scriptcache. This should be done after
     // PolicyScriptChecks(). This requires that all inputs either be in our
     // utxo set or in the mempool.
     bool ConsensusScriptChecks(const ATMPArgs &args, Workspace &ws)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
 
     // Try to add the transaction to the mempool, removing any conflicts first.
     // Returns true if the transaction is in the mempool after any size
     // limiting is performed, false otherwise.
     bool Finalize(const ATMPArgs &args, Workspace &ws)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
 
     // Submit all transactions to the mempool and call ConsensusScriptChecks to
     // add to the script cache - should only be called after successful
     // validation of all transactions in the package.
     // The package may end up partially-submitted after size limiting;
     // returns true if all transactions are successfully added to the mempool,
     // false otherwise.
     bool SubmitPackage(const ATMPArgs &args, std::vector<Workspace> &workspaces,
                        PackageValidationState &package_state,
                        std::map<const TxId, const MempoolAcceptResult> &results)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
 
 private:
     CTxMemPool &m_pool;
     CCoinsViewCache m_view;
     CCoinsViewMemPool m_viewmempool;
     CCoinsView m_dummy;
 
     Chainstate &m_active_chainstate;
 };
 
 bool MemPoolAccept::PreChecks(ATMPArgs &args, Workspace &ws) {
     AssertLockHeld(cs_main);
     AssertLockHeld(m_pool.cs);
     const CTransactionRef &ptx = ws.m_ptx;
     const CTransaction &tx = *ws.m_ptx;
     const TxId &txid = ws.m_ptx->GetId();
 
     // Copy/alias what we need out of args
     const int64_t nAcceptTime = args.m_accept_time;
     const bool bypass_limits = args.m_bypass_limits;
     std::vector<COutPoint> &coins_to_uncache = args.m_coins_to_uncache;
     const unsigned int heightOverride = args.m_heightOverride;
 
     // Alias what we need out of ws
     TxValidationState &state = ws.m_state;
     // Coinbase is only valid in a block, not as a loose transaction.
     if (!CheckRegularTransaction(tx, state)) {
         // state filled in by CheckRegularTransaction.
         return false;
     }
 
     // Rather not work on nonstandard transactions (unless -testnet)
     std::string reason;
     if (m_pool.m_require_standard &&
         !IsStandardTx(tx, m_pool.m_max_datacarrier_bytes,
                       m_pool.m_permit_bare_multisig,
                       m_pool.m_dust_relay_feerate, reason)) {
         return state.Invalid(TxValidationResult::TX_NOT_STANDARD, reason);
     }
 
     // Only accept nLockTime-using transactions that can be mined in the next
     // block; we don't want our mempool filled up with transactions that can't
     // be mined yet.
     TxValidationState ctxState;
     if (!ContextualCheckTransactionForCurrentBlock(
             m_active_chainstate.m_chain.Tip(),
             args.m_config.GetChainParams().GetConsensus(), tx, ctxState)) {
         // We copy the state from a dummy to ensure we don't increase the
         // ban score of peer for transaction that could be valid in the future.
         return state.Invalid(TxValidationResult::TX_PREMATURE_SPEND,
                              ctxState.GetRejectReason(),
                              ctxState.GetDebugMessage());
     }
 
     // Is it already in the memory pool?
     if (m_pool.exists(txid)) {
         return state.Invalid(TxValidationResult::TX_DUPLICATE,
                              "txn-already-in-mempool");
     }
 
     // Check for conflicts with in-memory transactions
     for (const CTxIn &txin : tx.vin) {
         const CTransaction *ptxConflicting = m_pool.GetConflictTx(txin.prevout);
         if (ptxConflicting) {
             // Disable replacement feature for good
             return state.Invalid(TxValidationResult::TX_CONFLICT,
                                  "txn-mempool-conflict");
         }
     }
 
     LockPoints lp;
     m_view.SetBackend(m_viewmempool);
 
     const CCoinsViewCache &coins_cache = m_active_chainstate.CoinsTip();
     // Do all inputs exist?
     for (const CTxIn &txin : tx.vin) {
         if (!coins_cache.HaveCoinInCache(txin.prevout)) {
             coins_to_uncache.push_back(txin.prevout);
         }
 
         // Note: this call may add txin.prevout to the coins cache
         // (coins_cache.cacheCoins) by way of FetchCoin(). It should be
         // removed later (via coins_to_uncache) if this tx turns out to be
         // invalid.
         if (!m_view.HaveCoin(txin.prevout)) {
             // Are inputs missing because we already have the tx?
             for (size_t out = 0; out < tx.vout.size(); out++) {
                 // Optimistically just do efficient check of cache for
                 // outputs.
                 if (coins_cache.HaveCoinInCache(COutPoint(txid, out))) {
                     return state.Invalid(TxValidationResult::TX_DUPLICATE,
                                          "txn-already-known");
                 }
             }
 
             // Otherwise assume this might be an orphan tx for which we just
             // haven't seen parents yet.
             return state.Invalid(TxValidationResult::TX_MISSING_INPUTS,
                                  "bad-txns-inputs-missingorspent");
         }
     }
 
     // Are the actual inputs available?
     if (!m_view.HaveInputs(tx)) {
         return state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY,
                              "bad-txns-inputs-spent");
     }
 
     // Bring the best block into scope.
     m_view.GetBestBlock();
 
     // we have all inputs cached now, so switch back to dummy (to protect
     // against bugs where we pull more inputs from disk that miss being
     // added to coins_to_uncache)
     m_view.SetBackend(m_dummy);
 
     assert(m_active_chainstate.m_blockman.LookupBlockIndex(
                m_view.GetBestBlock()) == m_active_chainstate.m_chain.Tip());
 
     // Only accept BIP68 sequence locked transactions that can be mined in
     // the next block; we don't want our mempool filled up with transactions
     // that can't be mined yet.
     // Pass in m_view which has all of the relevant inputs cached. Note that,
     // since m_view's backend was removed, it no longer pulls coins from the
     // mempool.
     if (!CheckSequenceLocksAtTip(m_active_chainstate.m_chain.Tip(), m_view, tx,
                                  &lp)) {
         return state.Invalid(TxValidationResult::TX_PREMATURE_SPEND,
                              "non-BIP68-final");
     }
 
     // The mempool holds txs for the next block, so pass height+1 to
     // CheckTxInputs
     if (!Consensus::CheckTxInputs(tx, state, m_view,
                                   m_active_chainstate.m_chain.Height() + 1,
                                   ws.m_base_fees)) {
         // state filled in by CheckTxInputs
         return false;
     }
 
     // Check for non-standard pay-to-script-hash in inputs
     if (m_pool.m_require_standard &&
         !AreInputsStandard(tx, m_view, ws.m_next_block_script_verify_flags)) {
         return state.Invalid(TxValidationResult::TX_INPUTS_NOT_STANDARD,
                              "bad-txns-nonstandard-inputs");
     }
 
     // ws.m_modified_fess includes any fee deltas from PrioritiseTransaction
     ws.m_modified_fees = ws.m_base_fees;
     m_pool.ApplyDelta(txid, ws.m_modified_fees);
 
     unsigned int nSize = tx.GetTotalSize();
 
     // No transactions are allowed below the min relay feerate except from
     // disconnected blocks.
     // Do not change this to use virtualsize without coordinating a network
     // policy upgrade.
     if (!bypass_limits &&
         ws.m_modified_fees < m_pool.m_min_relay_feerate.GetFee(nSize)) {
         return state.Invalid(
             TxValidationResult::TX_MEMPOOL_POLICY, "min relay fee not met",
             strprintf("%d < %d", ws.m_modified_fees,
                       m_pool.m_min_relay_feerate.GetFee(nSize)));
     }
 
     // Validate input scripts against standard script flags.
     const uint32_t scriptVerifyFlags =
         ws.m_next_block_script_verify_flags | STANDARD_SCRIPT_VERIFY_FLAGS;
     ws.m_precomputed_txdata = PrecomputedTransactionData{tx};
     if (!CheckInputScripts(tx, state, m_view, scriptVerifyFlags, true, false,
                            ws.m_precomputed_txdata, ws.m_sig_checks_standard)) {
         // State filled in by CheckInputScripts
         return false;
     }
 
     ws.m_entry = std::make_unique<CTxMemPoolEntry>(
         ptx, ws.m_base_fees, nAcceptTime,
         heightOverride ? heightOverride : m_active_chainstate.m_chain.Height(),
         ws.m_sig_checks_standard, lp);
 
     ws.m_vsize = ws.m_entry->GetTxVirtualSize();
 
     Amount mempoolRejectFee = m_pool.GetMinFee().GetFee(ws.m_vsize);
     if (!bypass_limits && mempoolRejectFee > Amount::zero() &&
         ws.m_modified_fees < mempoolRejectFee) {
         return state.Invalid(
             TxValidationResult::TX_MEMPOOL_POLICY, "mempool min fee not met",
             strprintf("%d < %d", ws.m_modified_fees, mempoolRejectFee));
     }
 
     return true;
 }
 
 bool MemPoolAccept::ConsensusScriptChecks(const ATMPArgs &args, Workspace &ws) {
     AssertLockHeld(cs_main);
     AssertLockHeld(m_pool.cs);
     const CTransaction &tx = *ws.m_ptx;
     const TxId &txid = tx.GetId();
     TxValidationState &state = ws.m_state;
 
     // Check again against the next block's script verification flags
     // to cache our script execution flags.
     //
     // This is also useful in case of bugs in the standard flags that cause
     // transactions to pass as valid when they're actually invalid. For
     // instance the STRICTENC flag was incorrectly allowing certain CHECKSIG
     // NOT scripts to pass, even though they were invalid.
     //
     // There is a similar check in CreateNewBlock() to prevent creating
     // invalid blocks (using TestBlockValidity), however allowing such
     // transactions into the mempool can be exploited as a DoS attack.
     int nSigChecksConsensus;
     if (!CheckInputsFromMempoolAndCache(
             tx, state, m_view, m_pool, ws.m_next_block_script_verify_flags,
             ws.m_precomputed_txdata, nSigChecksConsensus,
             m_active_chainstate.CoinsTip())) {
         // This can occur under some circumstances, if the node receives an
         // unrequested tx which is invalid due to new consensus rules not
         // being activated yet (during IBD).
         LogPrintf("BUG! PLEASE REPORT THIS! CheckInputScripts failed against "
                   "latest-block but not STANDARD flags %s, %s\n",
                   txid.ToString(), state.ToString());
         return Assume(false);
     }
 
     if (ws.m_sig_checks_standard != nSigChecksConsensus) {
         // We can't accept this transaction as we've used the standard count
         // for the mempool/mining, but the consensus count will be enforced
         // in validation (we don't want to produce bad block templates).
         return error(
             "%s: BUG! PLEASE REPORT THIS! SigChecks count differed between "
             "standard and consensus flags in %s",
             __func__, txid.ToString());
     }
     return true;
 }
 
 bool MemPoolAccept::Finalize(const ATMPArgs &args, Workspace &ws) {
     AssertLockHeld(cs_main);
     AssertLockHeld(m_pool.cs);
     const TxId &txid = ws.m_ptx->GetId();
     TxValidationState &state = ws.m_state;
     const bool bypass_limits = args.m_bypass_limits;
 
     // Store transaction in memory
     CTxMemPoolEntry *pentry = ws.m_entry.release();
     auto entry = CTxMemPoolEntryRef::acquire(pentry);
     m_pool.addUnchecked(entry);
 
     // Trim mempool and check if tx was trimmed.
     // If we are validating a package, don't trim here because we could evict a
     // previous transaction in the package. LimitMempoolSize() should be called
     // at the very end to make sure the mempool is still within limits and
     // package submission happens atomically.
     if (!args.m_package_submission && !bypass_limits) {
         m_pool.LimitSize(m_active_chainstate.CoinsTip());
         if (!m_pool.exists(txid)) {
             return state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY,
                                  "mempool full");
         }
     }
     return true;
 }
 
 // Get the coins spent by ptx from the coins_view. Assumes coins are present.
 static std::vector<Coin> getSpentCoins(const CTransactionRef &ptx,
                                        const CCoinsViewCache &coins_view) {
     std::vector<Coin> spent_coins;
     spent_coins.reserve(ptx->vin.size());
     for (const CTxIn &input : ptx->vin) {
         Coin coin;
         const bool coinFound = coins_view.GetCoin(input.prevout, coin);
         Assume(coinFound);
         spent_coins.push_back(std::move(coin));
     }
     return spent_coins;
 }
 
 bool MemPoolAccept::SubmitPackage(
     const ATMPArgs &args, std::vector<Workspace> &workspaces,
     PackageValidationState &package_state,
     std::map<const TxId, const MempoolAcceptResult> &results) {
     AssertLockHeld(cs_main);
     AssertLockHeld(m_pool.cs);
     // Sanity check: none of the transactions should be in the mempool.
     assert(std::all_of(
         workspaces.cbegin(), workspaces.cend(),
         [this](const auto &ws) { return !m_pool.exists(ws.m_ptx->GetId()); }));
 
     bool all_submitted = true;
     // ConsensusScriptChecks adds to the script cache and is therefore
     // consensus-critical; CheckInputsFromMempoolAndCache asserts that
     // transactions only spend coins available from the mempool or UTXO set.
     // Submit each transaction to the mempool immediately after calling
     // ConsensusScriptChecks to make the outputs available for subsequent
     // transactions.
     for (Workspace &ws : workspaces) {
         if (!ConsensusScriptChecks(args, ws)) {
             results.emplace(ws.m_ptx->GetId(),
                             MempoolAcceptResult::Failure(ws.m_state));
             // Since PreChecks() passed, this should never fail.
             all_submitted = Assume(false);
         }
 
         // If we call LimitMempoolSize() for each individual Finalize(), the
         // mempool will not take the transaction's descendant feerate into
         // account because it hasn't seen them yet. Also, we risk evicting a
         // transaction that a subsequent package transaction depends on.
         // Instead, allow the mempool to temporarily bypass limits, the maximum
         // package size) while submitting transactions individually and then
         // trim at the very end.
         if (!Finalize(args, ws)) {
             results.emplace(ws.m_ptx->GetId(),
                             MempoolAcceptResult::Failure(ws.m_state));
             // Since LimitMempoolSize() won't be called, this should never fail.
             all_submitted = Assume(false);
         }
     }
 
     // It may or may not be the case that all the transactions made it into the
     // mempool. Regardless, make sure we haven't exceeded max mempool size.
     m_pool.LimitSize(m_active_chainstate.CoinsTip());
     if (!all_submitted) {
         return false;
     }
 
     // Find the txids of the transactions that made it into the mempool. Allow
     // partial submission, but don't report success unless they all made it into
     // the mempool.
     for (Workspace &ws : workspaces) {
         if (m_pool.exists(ws.m_ptx->GetId())) {
             results.emplace(ws.m_ptx->GetId(), MempoolAcceptResult::Success(
                                                    ws.m_vsize, ws.m_base_fees));
             GetMainSignals().TransactionAddedToMempool(
                 ws.m_ptx,
                 std::make_shared<const std::vector<Coin>>(
                     getSpentCoins(ws.m_ptx, m_view)),
                 m_pool.GetAndIncrementSequence());
         } else {
             all_submitted = false;
             ws.m_state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY,
                                "mempool full");
             results.emplace(ws.m_ptx->GetId(),
                             MempoolAcceptResult::Failure(ws.m_state));
         }
     }
     return all_submitted;
 }
 
 MempoolAcceptResult
 MemPoolAccept::AcceptSingleTransaction(const CTransactionRef &ptx,
                                        ATMPArgs &args) {
     AssertLockHeld(cs_main);
     // mempool "read lock" (held through
     // GetMainSignals().TransactionAddedToMempool())
     LOCK(m_pool.cs);
 
     const CBlockIndex *tip = m_active_chainstate.m_chain.Tip();
 
     Workspace ws(ptx,
                  GetNextBlockScriptFlags(tip, m_active_chainstate.m_chainman));
 
     // Perform the inexpensive checks first and avoid hashing and signature
     // verification unless those checks pass, to mitigate CPU exhaustion
     // denial-of-service attacks.
     if (!PreChecks(args, ws)) {
         return MempoolAcceptResult::Failure(ws.m_state);
     }
 
     if (!ConsensusScriptChecks(args, ws)) {
         return MempoolAcceptResult::Failure(ws.m_state);
     }
 
     const TxId txid = ptx->GetId();
 
     // Mempool sanity check -- in our new mempool no tx can be added if its
     // outputs are already spent in the mempool (that is, no children before
     // parents allowed; the mempool must be consistent at all times).
     //
     // This means that on reorg, the disconnectpool *must* always import
     // the existing mempool tx's, clear the mempool, and then re-add
     // remaining tx's in topological order via this function. Our new mempool
     // has fast adds, so this is ok.
     if (auto it = m_pool.mapNextTx.lower_bound(COutPoint{txid, 0});
         it != m_pool.mapNextTx.end() && it->first->GetTxId() == txid) {
         LogPrintf("%s: BUG! PLEASE REPORT THIS! Attempt to add txid %s, but "
                   "its outputs are already spent in the "
                   "mempool\n",
                   __func__, txid.ToString());
         ws.m_state.Invalid(TxValidationResult::TX_CHILD_BEFORE_PARENT,
                            "txn-child-before-parent");
         return MempoolAcceptResult::Failure(ws.m_state);
     }
 
     // Tx was accepted, but not added
     if (args.m_test_accept) {
         return MempoolAcceptResult::Success(ws.m_vsize, ws.m_base_fees);
     }
 
     if (!Finalize(args, ws)) {
         return MempoolAcceptResult::Failure(ws.m_state);
     }
 
     GetMainSignals().TransactionAddedToMempool(
         ptx,
         std::make_shared<const std::vector<Coin>>(getSpentCoins(ptx, m_view)),
         m_pool.GetAndIncrementSequence());
 
     return MempoolAcceptResult::Success(ws.m_vsize, ws.m_base_fees);
 }
 
 PackageMempoolAcceptResult MemPoolAccept::AcceptMultipleTransactions(
     const std::vector<CTransactionRef> &txns, ATMPArgs &args) {
     AssertLockHeld(cs_main);
 
     // These context-free package limits can be done before taking the mempool
     // lock.
     PackageValidationState package_state;
     if (!CheckPackage(txns, package_state)) {
         return PackageMempoolAcceptResult(package_state, {});
     }
 
     std::vector<Workspace> workspaces{};
     workspaces.reserve(txns.size());
     std::transform(
         txns.cbegin(), txns.cend(), std::back_inserter(workspaces),
         [this](const auto &tx) {
             return Workspace(
                 tx, GetNextBlockScriptFlags(m_active_chainstate.m_chain.Tip(),
                                             m_active_chainstate.m_chainman));
         });
     std::map<const TxId, const MempoolAcceptResult> results;
 
     LOCK(m_pool.cs);
 
     // Do all PreChecks first and fail fast to avoid running expensive script
     // checks when unnecessary.
     for (Workspace &ws : workspaces) {
         if (!PreChecks(args, ws)) {
             package_state.Invalid(PackageValidationResult::PCKG_TX,
                                   "transaction failed");
             // Exit early to avoid doing pointless work. Update the failed tx
             // result; the rest are unfinished.
             results.emplace(ws.m_ptx->GetId(),
                             MempoolAcceptResult::Failure(ws.m_state));
             return PackageMempoolAcceptResult(package_state,
                                               std::move(results));
         }
         // Make the coins created by this transaction available for subsequent
         // transactions in the package to spend.
         m_viewmempool.PackageAddTransaction(ws.m_ptx);
         if (args.m_test_accept) {
             // When test_accept=true, transactions that pass PreChecks
             // are valid because there are no further mempool checks (passing
             // PreChecks implies passing ConsensusScriptChecks).
             results.emplace(ws.m_ptx->GetId(), MempoolAcceptResult::Success(
                                                    ws.m_vsize, ws.m_base_fees));
         }
     }
 
     if (args.m_test_accept) {
         return PackageMempoolAcceptResult(package_state, std::move(results));
     }
 
     if (!SubmitPackage(args, workspaces, package_state, results)) {
         package_state.Invalid(PackageValidationResult::PCKG_TX,
                               "submission failed");
         return PackageMempoolAcceptResult(package_state, std::move(results));
     }
 
     return PackageMempoolAcceptResult(package_state, std::move(results));
 }
 
 PackageMempoolAcceptResult MemPoolAccept::AcceptPackage(const Package &package,
                                                         ATMPArgs &args) {
     AssertLockHeld(cs_main);
     PackageValidationState package_state;
 
     // Check that the package is well-formed. If it isn't, we won't try to
     // validate any of the transactions and thus won't return any
     // MempoolAcceptResults, just a package-wide error.
 
     // Context-free package checks.
     if (!CheckPackage(package, package_state)) {
         return PackageMempoolAcceptResult(package_state, {});
     }
 
     // All transactions in the package must be a parent of the last transaction.
     // This is just an opportunity for us to fail fast on a context-free check
     // without taking the mempool lock.
     if (!IsChildWithParents(package)) {
         package_state.Invalid(PackageValidationResult::PCKG_POLICY,
                               "package-not-child-with-parents");
         return PackageMempoolAcceptResult(package_state, {});
     }
 
     // IsChildWithParents() guarantees the package is > 1 transactions.
     assert(package.size() > 1);
     // The package must be 1 child with all of its unconfirmed parents. The
     // package is expected to be sorted, so the last transaction is the child.
     const auto &child = package.back();
     std::unordered_set<TxId, SaltedTxIdHasher> unconfirmed_parent_txids;
     std::transform(
         package.cbegin(), package.cend() - 1,
         std::inserter(unconfirmed_parent_txids, unconfirmed_parent_txids.end()),
         [](const auto &tx) { return tx->GetId(); });
 
     // All child inputs must refer to a preceding package transaction or a
     // confirmed UTXO. The only way to verify this is to look up the child's
     // inputs in our current coins view (not including mempool), and enforce
     // that all parents not present in the package be available at chain tip.
     // Since this check can bring new coins into the coins cache, keep track of
     // these coins and uncache them if we don't end up submitting this package
     // to the mempool.
     const CCoinsViewCache &coins_tip_cache = m_active_chainstate.CoinsTip();
     for (const auto &input : child->vin) {
         if (!coins_tip_cache.HaveCoinInCache(input.prevout)) {
             args.m_coins_to_uncache.push_back(input.prevout);
         }
     }
     // Using the MemPoolAccept m_view cache allows us to look up these same
     // coins faster later. This should be connecting directly to CoinsTip, not
     // to m_viewmempool, because we specifically require inputs to be confirmed
     // if they aren't in the package.
     m_view.SetBackend(m_active_chainstate.CoinsTip());
     const auto package_or_confirmed = [this, &unconfirmed_parent_txids](
                                           const auto &input) {
         return unconfirmed_parent_txids.count(input.prevout.GetTxId()) > 0 ||
                m_view.HaveCoin(input.prevout);
     };
     if (!std::all_of(child->vin.cbegin(), child->vin.cend(),
                      package_or_confirmed)) {
         package_state.Invalid(PackageValidationResult::PCKG_POLICY,
                               "package-not-child-with-unconfirmed-parents");
         return PackageMempoolAcceptResult(package_state, {});
     }
     // Protect against bugs where we pull more inputs from disk that miss being
     // added to coins_to_uncache. The backend will be connected again when
     // needed in PreChecks.
     m_view.SetBackend(m_dummy);
 
     LOCK(m_pool.cs);
     std::map<const TxId, const MempoolAcceptResult> results;
     // Node operators are free to set their mempool policies however they
     // please, nodes may receive transactions in different orders, and malicious
     // counterparties may try to take advantage of policy differences to pin or
     // delay propagation of transactions. As such, it's possible for some
     // package transaction(s) to already be in the mempool, and we don't want to
     // reject the entire package in that case (as that could be a censorship
     // vector). De-duplicate the transactions that are already in the mempool,
     // and only call AcceptMultipleTransactions() with the new transactions.
     // This ensures we don't double-count transaction counts and sizes when
     // checking ancestor/descendant limits, or double-count transaction fees for
     // fee-related policy.
     std::vector<CTransactionRef> txns_new;
     for (const auto &tx : package) {
         const auto &txid = tx->GetId();
         // An already confirmed tx is treated as one not in mempool, because all
         // we know is that the inputs aren't available.
         if (m_pool.exists(txid)) {
             // Exact transaction already exists in the mempool.
             auto iter = m_pool.GetIter(txid);
             assert(iter != std::nullopt);
             results.emplace(txid, MempoolAcceptResult::MempoolTx(
                                       (*iter.value())->GetTxSize(),
                                       (*iter.value())->GetFee()));
         } else {
             // Transaction does not already exist in the mempool.
             txns_new.push_back(tx);
         }
     }
 
     // Nothing to do if the entire package has already been submitted.
     if (txns_new.empty()) {
         return PackageMempoolAcceptResult(package_state, std::move(results));
     }
     // Validate the (deduplicated) transactions as a package.
     auto submission_result = AcceptMultipleTransactions(txns_new, args);
     // Include already-in-mempool transaction results in the final result.
     for (const auto &[txid, mempoolaccept_res] : results) {
         submission_result.m_tx_results.emplace(txid, mempoolaccept_res);
     }
     return submission_result;
 }
 } // namespace
 
 MempoolAcceptResult AcceptToMemoryPool(Chainstate &active_chainstate,
                                        const CTransactionRef &tx,
                                        int64_t accept_time, bool bypass_limits,
                                        bool test_accept,
                                        unsigned int heightOverride) {
     AssertLockHeld(::cs_main);
     assert(active_chainstate.GetMempool() != nullptr);
     CTxMemPool &pool{*active_chainstate.GetMempool()};
 
     std::vector<COutPoint> coins_to_uncache;
     auto args = MemPoolAccept::ATMPArgs::SingleAccept(
         active_chainstate.m_chainman.GetConfig(), accept_time, bypass_limits,
         coins_to_uncache, test_accept, heightOverride);
     const MempoolAcceptResult result = MemPoolAccept(pool, active_chainstate)
                                            .AcceptSingleTransaction(tx, args);
     if (result.m_result_type != MempoolAcceptResult::ResultType::VALID) {
         // Remove coins that were not present in the coins cache before calling
         // ATMPW; this is to prevent memory DoS in case we receive a large
         // number of invalid transactions that attempt to overrun the in-memory
         // coins cache
         // (`CCoinsViewCache::cacheCoins`).
 
         for (const COutPoint &outpoint : coins_to_uncache) {
             active_chainstate.CoinsTip().Uncache(outpoint);
         }
     }
 
     // After we've (potentially) uncached entries, ensure our coins cache is
     // still within its size limits
     BlockValidationState stateDummy;
     active_chainstate.FlushStateToDisk(stateDummy, FlushStateMode::PERIODIC);
     return result;
 }
 
 PackageMempoolAcceptResult ProcessNewPackage(Chainstate &active_chainstate,
                                              CTxMemPool &pool,
                                              const Package &package,
                                              bool test_accept) {
     AssertLockHeld(cs_main);
     assert(!package.empty());
     assert(std::all_of(package.cbegin(), package.cend(),
                        [](const auto &tx) { return tx != nullptr; }));
 
     const Config &config = active_chainstate.m_chainman.GetConfig();
 
     std::vector<COutPoint> coins_to_uncache;
     const auto result = [&]() EXCLUSIVE_LOCKS_REQUIRED(cs_main) {
         AssertLockHeld(cs_main);
         if (test_accept) {
             auto args = MemPoolAccept::ATMPArgs::PackageTestAccept(
                 config, GetTime(), coins_to_uncache);
             return MemPoolAccept(pool, active_chainstate)
                 .AcceptMultipleTransactions(package, args);
         } else {
             auto args = MemPoolAccept::ATMPArgs::PackageChildWithParents(
                 config, GetTime(), coins_to_uncache);
             return MemPoolAccept(pool, active_chainstate)
                 .AcceptPackage(package, args);
         }
     }();
 
     // Uncache coins pertaining to transactions that were not submitted to the
     // mempool.
     if (test_accept || result.m_state.IsInvalid()) {
         for (const COutPoint &hashTx : coins_to_uncache) {
             active_chainstate.CoinsTip().Uncache(hashTx);
         }
     }
     // Ensure the coins cache is still within limits.
     BlockValidationState state_dummy;
     active_chainstate.FlushStateToDisk(state_dummy, FlushStateMode::PERIODIC);
     return result;
 }
 
 Amount GetBlockSubsidy(int nHeight, const Consensus::Params &consensusParams) {
     int halvings = nHeight / consensusParams.nSubsidyHalvingInterval;
     // Force block reward to zero when right shift is undefined.
     if (halvings >= 64) {
         return Amount::zero();
     }
 
     Amount nSubsidy = 50 * COIN;
     // Subsidy is cut in half every 210,000 blocks which will occur
     // approximately every 4 years.
     return ((nSubsidy / SATOSHI) >> halvings) * SATOSHI;
 }
 
 CoinsViews::CoinsViews(std::string ldb_name, size_t cache_size_bytes,
                        bool in_memory, bool should_wipe)
     : m_dbview(gArgs.GetDataDirNet() / ldb_name, cache_size_bytes, in_memory,
                should_wipe),
       m_catcherview(&m_dbview) {}
 
 void CoinsViews::InitCache() {
     AssertLockHeld(::cs_main);
     m_cacheview = std::make_unique<CCoinsViewCache>(&m_catcherview);
 }
 
 Chainstate::Chainstate(CTxMemPool *mempool, BlockManager &blockman,
                        ChainstateManager &chainman,
                        std::optional<BlockHash> from_snapshot_blockhash)
     : m_mempool(mempool), m_blockman(blockman), m_chainman(chainman),
       m_from_snapshot_blockhash(from_snapshot_blockhash) {}
 
 void Chainstate::InitCoinsDB(size_t cache_size_bytes, bool in_memory,
                              bool should_wipe, std::string leveldb_name) {
     if (m_from_snapshot_blockhash) {
         leveldb_name += node::SNAPSHOT_CHAINSTATE_SUFFIX;
     }
     m_coins_views = std::make_unique<CoinsViews>(leveldb_name, cache_size_bytes,
                                                  in_memory, should_wipe);
 }
 
 void Chainstate::InitCoinsCache(size_t cache_size_bytes) {
     AssertLockHeld(::cs_main);
     assert(m_coins_views != nullptr);
     m_coinstip_cache_size_bytes = cache_size_bytes;
     m_coins_views->InitCache();
 }
 
 // Note that though this is marked const, we may end up modifying
 // `m_cached_finished_ibd`, which is a performance-related implementation
 // detail. This function must be marked `const` so that `CValidationInterface`
 // clients (which are given a `const Chainstate*`) can call it.
 //
 bool Chainstate::IsInitialBlockDownload() const {
     // Optimization: pre-test latch before taking the lock.
     if (m_cached_finished_ibd.load(std::memory_order_relaxed)) {
         return false;
     }
 
     LOCK(cs_main);
     if (m_cached_finished_ibd.load(std::memory_order_relaxed)) {
         return false;
     }
     if (m_chainman.m_blockman.LoadingBlocks()) {
         return true;
     }
     if (m_chain.Tip() == nullptr) {
         return true;
     }
     if (m_chain.Tip()->nChainWork < m_chainman.MinimumChainWork()) {
         return true;
     }
     if (m_chain.Tip()->Time() <
         Now<NodeSeconds>() - m_chainman.m_options.max_tip_age) {
         return true;
     }
     LogPrintf("Leaving InitialBlockDownload (latching to false)\n");
     m_cached_finished_ibd.store(true, std::memory_order_relaxed);
     return false;
 }
 
 static void AlertNotify(const std::string &strMessage) {
     uiInterface.NotifyAlertChanged();
 #if defined(HAVE_SYSTEM)
     std::string strCmd = gArgs.GetArg("-alertnotify", "");
     if (strCmd.empty()) {
         return;
     }
 
     // Alert text should be plain ascii coming from a trusted source, but to be
     // safe we first strip anything not in safeChars, then add single quotes
     // around the whole string before passing it to the shell:
     std::string singleQuote("'");
     std::string safeStatus = SanitizeString(strMessage);
     safeStatus = singleQuote + safeStatus + singleQuote;
     ReplaceAll(strCmd, "%s", safeStatus);
 
     std::thread t(runCommand, strCmd);
     // thread runs free
     t.detach();
 #endif
 }
 
 void Chainstate::CheckForkWarningConditions() {
     AssertLockHeld(cs_main);
 
     // Before we get past initial download, we cannot reliably alert about forks
     // (we assume we don't get stuck on a fork before finishing our initial
     // sync)
     if (IsInitialBlockDownload()) {
         return;
     }
 
     // If our best fork is no longer within 72 blocks (+/- 12 hours if no one
     // mines it) of our head, or if it is back on the active chain, drop it
     if (m_best_fork_tip && (m_chain.Height() - m_best_fork_tip->nHeight >= 72 ||
                             m_chain.Contains(m_best_fork_tip))) {
         m_best_fork_tip = nullptr;
     }
 
     if (m_best_fork_tip ||
         (m_chainman.m_best_invalid &&
          m_chainman.m_best_invalid->nChainWork >
              m_chain.Tip()->nChainWork + (GetBlockProof(*m_chain.Tip()) * 6))) {
         if (!GetfLargeWorkForkFound() && m_best_fork_base) {
             std::string warning =
                 std::string("'Warning: Large-work fork detected, forking after "
                             "block ") +
                 m_best_fork_base->phashBlock->ToString() + std::string("'");
             AlertNotify(warning);
         }
 
         if (m_best_fork_tip && m_best_fork_base) {
             LogPrintf("%s: Warning: Large fork found\n  forking the "
                       "chain at height %d (%s)\n  lasting to height %d "
                       "(%s).\nChain state database corruption likely.\n",
                       __func__, m_best_fork_base->nHeight,
                       m_best_fork_base->phashBlock->ToString(),
                       m_best_fork_tip->nHeight,
                       m_best_fork_tip->phashBlock->ToString());
             SetfLargeWorkForkFound(true);
         } else {
             LogPrintf("%s: Warning: Found invalid chain at least ~6 blocks "
                       "longer than our best chain.\nChain state database "
                       "corruption likely.\n",
                       __func__);
             SetfLargeWorkInvalidChainFound(true);
         }
     } else {
         SetfLargeWorkForkFound(false);
         SetfLargeWorkInvalidChainFound(false);
     }
 }
 
 void Chainstate::CheckForkWarningConditionsOnNewFork(
     CBlockIndex *pindexNewForkTip) {
     AssertLockHeld(cs_main);
 
     // If we are on a fork that is sufficiently large, set a warning flag.
     const CBlockIndex *pfork = m_chain.FindFork(pindexNewForkTip);
 
     // We define a condition where we should warn the user about as a fork of at
     // least 7 blocks with a tip within 72 blocks (+/- 12 hours if no one mines
     // it) of ours. We use 7 blocks rather arbitrarily as it represents just
     // under 10% of sustained network hash rate operating on the fork, or a
     // chain that is entirely longer than ours and invalid (note that this
     // should be detected by both). We define it this way because it allows us
     // to only store the highest fork tip (+ base) which meets the 7-block
     // condition and from this always have the most-likely-to-cause-warning fork
     if (pfork &&
         (!m_best_fork_tip ||
          pindexNewForkTip->nHeight > m_best_fork_tip->nHeight) &&
         pindexNewForkTip->nChainWork - pfork->nChainWork >
             (GetBlockProof(*pfork) * 7) &&
         m_chain.Height() - pindexNewForkTip->nHeight < 72) {
         m_best_fork_tip = pindexNewForkTip;
         m_best_fork_base = pfork;
     }
 
     CheckForkWarningConditions();
 }
 
 // Called both upon regular invalid block discovery *and* InvalidateBlock
 void Chainstate::InvalidChainFound(CBlockIndex *pindexNew) {
     AssertLockHeld(cs_main);
     if (!m_chainman.m_best_invalid ||
         pindexNew->nChainWork > m_chainman.m_best_invalid->nChainWork) {
         m_chainman.m_best_invalid = pindexNew;
     }
     if (m_chainman.m_best_header != nullptr &&
         m_chainman.m_best_header->GetAncestor(pindexNew->nHeight) ==
             pindexNew) {
         m_chainman.m_best_header = m_chain.Tip();
     }
 
     // If the invalid chain found is supposed to be finalized, we need to move
     // back the finalization point.
     if (IsBlockAvalancheFinalized(pindexNew)) {
         LOCK(cs_avalancheFinalizedBlockIndex);
         m_avalancheFinalizedBlockIndex = pindexNew->pprev;
     }
 
     LogPrintf("%s: invalid block=%s  height=%d  log2_work=%f  date=%s\n",
               __func__, pindexNew->GetBlockHash().ToString(),
               pindexNew->nHeight,
               log(pindexNew->nChainWork.getdouble()) / log(2.0),
               FormatISO8601DateTime(pindexNew->GetBlockTime()));
     CBlockIndex *tip = m_chain.Tip();
     assert(tip);
     LogPrintf("%s:  current best=%s  height=%d  log2_work=%f  date=%s\n",
               __func__, tip->GetBlockHash().ToString(), m_chain.Height(),
               log(tip->nChainWork.getdouble()) / log(2.0),
               FormatISO8601DateTime(tip->GetBlockTime()));
 }
 
 // Same as InvalidChainFound, above, except not called directly from
 // InvalidateBlock, which does its own setBlockIndexCandidates management.
 void Chainstate::InvalidBlockFound(CBlockIndex *pindex,
                                    const BlockValidationState &state) {
     AssertLockHeld(cs_main);
     if (state.GetResult() != BlockValidationResult::BLOCK_MUTATED) {
         pindex->nStatus = pindex->nStatus.withFailed();
         m_chainman.m_failed_blocks.insert(pindex);
         m_blockman.m_dirty_blockindex.insert(pindex);
         InvalidChainFound(pindex);
     }
 }
 
 void SpendCoins(CCoinsViewCache &view, const CTransaction &tx, CTxUndo &txundo,
                 int nHeight) {
     // Mark inputs spent.
     if (tx.IsCoinBase()) {
         return;
     }
 
     txundo.vprevout.reserve(tx.vin.size());
     for (const CTxIn &txin : tx.vin) {
         txundo.vprevout.emplace_back();
         bool is_spent = view.SpendCoin(txin.prevout, &txundo.vprevout.back());
         assert(is_spent);
     }
 }
 
 void UpdateCoins(CCoinsViewCache &view, const CTransaction &tx, CTxUndo &txundo,
                  int nHeight) {
     SpendCoins(view, tx, txundo, nHeight);
     AddCoins(view, tx, nHeight);
 }
 
 bool CScriptCheck::operator()() {
     const CScript &scriptSig = ptxTo->vin[nIn].scriptSig;
     if (!VerifyScript(scriptSig, m_tx_out.scriptPubKey, nFlags,
                       CachingTransactionSignatureChecker(
                           ptxTo, nIn, m_tx_out.nValue, cacheStore, txdata),
                       metrics, &error)) {
         return false;
     }
     if ((pTxLimitSigChecks &&
          !pTxLimitSigChecks->consume_and_check(metrics.nSigChecks)) ||
         (pBlockLimitSigChecks &&
          !pBlockLimitSigChecks->consume_and_check(metrics.nSigChecks))) {
         // we can't assign a meaningful script error (since the script
         // succeeded), but remove the ScriptError::OK which could be
         // misinterpreted.
         error = ScriptError::SIGCHECKS_LIMIT_EXCEEDED;
         return false;
     }
     return true;
 }
 
 bool CheckInputScripts(const CTransaction &tx, TxValidationState &state,
                        const CCoinsViewCache &inputs, const uint32_t flags,
                        bool sigCacheStore, bool scriptCacheStore,
                        const PrecomputedTransactionData &txdata,
                        int &nSigChecksOut, TxSigCheckLimiter &txLimitSigChecks,
                        CheckInputsLimiter *pBlockLimitSigChecks,
                        std::vector<CScriptCheck> *pvChecks) {
     AssertLockHeld(cs_main);
     assert(!tx.IsCoinBase());
 
     if (pvChecks) {
         pvChecks->reserve(tx.vin.size());
     }
 
     // First check if script executions have been cached with the same flags.
     // Note that this assumes that the inputs provided are correct (ie that the
     // transaction hash which is in tx's prevouts properly commits to the
     // scriptPubKey in the inputs view of that transaction).
     ScriptCacheKey hashCacheEntry(tx, flags);
     if (IsKeyInScriptCache(hashCacheEntry, !scriptCacheStore, nSigChecksOut)) {
         if (!txLimitSigChecks.consume_and_check(nSigChecksOut) ||
             (pBlockLimitSigChecks &&
              !pBlockLimitSigChecks->consume_and_check(nSigChecksOut))) {
             return state.Invalid(TxValidationResult::TX_CONSENSUS,
                                  "too-many-sigchecks");
         }
         return true;
     }
 
     int nSigChecksTotal = 0;
 
     for (size_t i = 0; i < tx.vin.size(); i++) {
         const COutPoint &prevout = tx.vin[i].prevout;
         const Coin &coin = inputs.AccessCoin(prevout);
         assert(!coin.IsSpent());
 
         // We very carefully only pass in things to CScriptCheck which are
         // clearly committed to by tx's hash. This provides a sanity
         // check that our caching is not introducing consensus failures through
         // additional data in, eg, the coins being spent being checked as a part
         // of CScriptCheck.
 
         // Verify signature
         CScriptCheck check(coin.GetTxOut(), tx, i, flags, sigCacheStore, txdata,
                            &txLimitSigChecks, pBlockLimitSigChecks);
 
         // If pvChecks is not null, defer the check execution to the caller.
         if (pvChecks) {
             pvChecks->push_back(std::move(check));
             continue;
         }
 
         if (!check()) {
             ScriptError scriptError = check.GetScriptError();
             // Compute flags without the optional standardness flags.
             // This differs from MANDATORY_SCRIPT_VERIFY_FLAGS as it contains
             // additional upgrade flags (see AcceptToMemoryPoolWorker variable
             // extraFlags).
             uint32_t mandatoryFlags =
                 flags & ~STANDARD_NOT_MANDATORY_VERIFY_FLAGS;
             if (flags != mandatoryFlags) {
                 // Check whether the failure was caused by a non-mandatory
                 // script verification check. If so, ensure we return
                 // NOT_STANDARD instead of CONSENSUS to avoid downstream users
                 // splitting the network between upgraded and non-upgraded nodes
                 // by banning CONSENSUS-failing data providers.
                 CScriptCheck check2(coin.GetTxOut(), tx, i, mandatoryFlags,
                                     sigCacheStore, txdata);
                 if (check2()) {
                     return state.Invalid(
                         TxValidationResult::TX_NOT_STANDARD,
                         strprintf("non-mandatory-script-verify-flag (%s)",
                                   ScriptErrorString(scriptError)));
                 }
                 // update the error message to reflect the mandatory violation.
                 scriptError = check2.GetScriptError();
             }
 
             // MANDATORY flag failures correspond to
             // TxValidationResult::TX_CONSENSUS. Because CONSENSUS failures are
             // the most serious case of validation failures, we may need to
             // consider using RECENT_CONSENSUS_CHANGE for any script failure
             // that could be due to non-upgraded nodes which we may want to
             // support, to avoid splitting the network (but this depends on the
             // details of how net_processing handles such errors).
             return state.Invalid(
                 TxValidationResult::TX_CONSENSUS,
                 strprintf("mandatory-script-verify-flag-failed (%s)",
                           ScriptErrorString(scriptError)));
         }
 
         nSigChecksTotal += check.GetScriptExecutionMetrics().nSigChecks;
     }
 
     nSigChecksOut = nSigChecksTotal;
 
     if (scriptCacheStore && !pvChecks) {
         // We executed all of the provided scripts, and were told to cache the
         // result. Do so now.
         AddKeyInScriptCache(hashCacheEntry, nSigChecksTotal);
     }
 
     return true;
 }
 
 bool AbortNode(BlockValidationState &state, const std::string &strMessage,
                const bilingual_str &userMessage) {
     AbortNode(strMessage, userMessage);
     return state.Error(strMessage);
 }
 
 /** Restore the UTXO in a Coin at a given COutPoint. */
 DisconnectResult UndoCoinSpend(Coin &&undo, CCoinsViewCache &view,
                                const COutPoint &out) {
     bool fClean = true;
 
     if (view.HaveCoin(out)) {
         // Overwriting transaction output.
         fClean = false;
     }
 
     if (undo.GetHeight() == 0) {
         // Missing undo metadata (height and coinbase). Older versions included
         // this information only in undo records for the last spend of a
         // transactions' outputs. This implies that it must be present for some
         // other output of the same tx.
         const Coin &alternate = AccessByTxid(view, out.GetTxId());
         if (alternate.IsSpent()) {
             // Adding output for transaction without known metadata
             return DisconnectResult::FAILED;
         }
 
         // This is somewhat ugly, but hopefully utility is limited. This is only
         // useful when working from legacy on disck data. In any case, putting
         // the correct information in there doesn't hurt.
         const_cast<Coin &>(undo) = Coin(undo.GetTxOut(), alternate.GetHeight(),
                                         alternate.IsCoinBase());
     }
 
     // If the coin already exists as an unspent coin in the cache, then the
     // possible_overwrite parameter to AddCoin must be set to true. We have
     // already checked whether an unspent coin exists above using HaveCoin, so
     // we don't need to guess. When fClean is false, an unspent coin already
     // existed and it is an overwrite.
     view.AddCoin(out, std::move(undo), !fClean);
 
     return fClean ? DisconnectResult::OK : DisconnectResult::UNCLEAN;
 }
 
 /**
  * Undo the effects of this block (with given index) on the UTXO set represented
  * by coins. When FAILED is returned, view is left in an indeterminate state.
  */
 DisconnectResult Chainstate::DisconnectBlock(const CBlock &block,
                                              const CBlockIndex *pindex,
                                              CCoinsViewCache &view) {
     AssertLockHeld(::cs_main);
     CBlockUndo blockUndo;
     if (!UndoReadFromDisk(blockUndo, pindex)) {
         error("DisconnectBlock(): failure reading undo data");
         return DisconnectResult::FAILED;
     }
 
     return ApplyBlockUndo(std::move(blockUndo), block, pindex, view);
 }
 
 DisconnectResult ApplyBlockUndo(CBlockUndo &&blockUndo, const CBlock &block,
                                 const CBlockIndex *pindex,
                                 CCoinsViewCache &view) {
     bool fClean = true;
 
     if (blockUndo.vtxundo.size() + 1 != block.vtx.size()) {
         error("DisconnectBlock(): block and undo data inconsistent");
         return DisconnectResult::FAILED;
     }
 
     // First, restore inputs.
     for (size_t i = 1; i < block.vtx.size(); i++) {
         const CTransaction &tx = *(block.vtx[i]);
         CTxUndo &txundo = blockUndo.vtxundo[i - 1];
         if (txundo.vprevout.size() != tx.vin.size()) {
             error("DisconnectBlock(): transaction and undo data inconsistent");
             return DisconnectResult::FAILED;
         }
 
         for (size_t j = 0; j < tx.vin.size(); j++) {
             const COutPoint &out = tx.vin[j].prevout;
             DisconnectResult res =
                 UndoCoinSpend(std::move(txundo.vprevout[j]), view, out);
             if (res == DisconnectResult::FAILED) {
                 return DisconnectResult::FAILED;
             }
             fClean = fClean && res != DisconnectResult::UNCLEAN;
         }
         // At this point, all of txundo.vprevout should have been moved out.
     }
 
     // Second, revert created outputs.
     for (const auto &ptx : block.vtx) {
         const CTransaction &tx = *ptx;
         const TxId &txid = tx.GetId();
         const bool is_coinbase = tx.IsCoinBase();
 
         // Check that all outputs are available and match the outputs in the
         // block itself exactly.
         for (size_t o = 0; o < tx.vout.size(); o++) {
             if (tx.vout[o].scriptPubKey.IsUnspendable()) {
                 continue;
             }
 
             COutPoint out(txid, o);
             Coin coin;
             bool is_spent = view.SpendCoin(out, &coin);
             if (!is_spent || tx.vout[o] != coin.GetTxOut() ||
                 uint32_t(pindex->nHeight) != coin.GetHeight() ||
                 is_coinbase != coin.IsCoinBase()) {
                 // transaction output mismatch
                 fClean = false;
             }
         }
     }
 
     // Move best block pointer to previous block.
     view.SetBestBlock(block.hashPrevBlock);
 
     return fClean ? DisconnectResult::OK : DisconnectResult::UNCLEAN;
 }
 
 static CCheckQueue<CScriptCheck> scriptcheckqueue(128);
 
 void StartScriptCheckWorkerThreads(int threads_num) {
     scriptcheckqueue.StartWorkerThreads(threads_num);
 }
 
 void StopScriptCheckWorkerThreads() {
     scriptcheckqueue.StopWorkerThreads();
 }
 
 // Returns the script flags which should be checked for the block after
 // the given block.
 static uint32_t GetNextBlockScriptFlags(const CBlockIndex *pindex,
                                         const ChainstateManager &chainman) {
     const Consensus::Params &consensusparams = chainman.GetConsensus();
 
     uint32_t flags = SCRIPT_VERIFY_NONE;
 
     // Enforce P2SH (BIP16)
     if (DeploymentActiveAfter(pindex, chainman, Consensus::DEPLOYMENT_P2SH)) {
         flags |= SCRIPT_VERIFY_P2SH;
     }
 
     // Enforce the DERSIG (BIP66) rule.
     if (DeploymentActiveAfter(pindex, chainman, Consensus::DEPLOYMENT_DERSIG)) {
         flags |= SCRIPT_VERIFY_DERSIG;
     }
 
     // Start enforcing CHECKLOCKTIMEVERIFY (BIP65) rule.
     if (DeploymentActiveAfter(pindex, chainman, Consensus::DEPLOYMENT_CLTV)) {
         flags |= SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY;
     }
 
     // Start enforcing CSV (BIP68, BIP112 and BIP113) rule.
     if (DeploymentActiveAfter(pindex, chainman, Consensus::DEPLOYMENT_CSV)) {
         flags |= SCRIPT_VERIFY_CHECKSEQUENCEVERIFY;
     }
 
     // If the UAHF is enabled, we start accepting replay protected txns
     if (IsUAHFenabled(consensusparams, pindex)) {
         flags |= SCRIPT_VERIFY_STRICTENC;
         flags |= SCRIPT_ENABLE_SIGHASH_FORKID;
     }
 
     // If the DAA HF is enabled, we start rejecting transaction that use a high
     // s in their signature. We also make sure that signature that are supposed
     // to fail (for instance in multisig or other forms of smart contracts) are
     // null.
     if (IsDAAEnabled(consensusparams, pindex)) {
         flags |= SCRIPT_VERIFY_LOW_S;
         flags |= SCRIPT_VERIFY_NULLFAIL;
     }
 
     // When the magnetic anomaly fork is enabled, we start accepting
     // transactions using the OP_CHECKDATASIG opcode and it's verify
     // alternative. We also start enforcing push only signatures and
     // clean stack.
     if (IsMagneticAnomalyEnabled(consensusparams, pindex)) {
         flags |= SCRIPT_VERIFY_SIGPUSHONLY;
         flags |= SCRIPT_VERIFY_CLEANSTACK;
     }
 
     if (IsGravitonEnabled(consensusparams, pindex)) {
         flags |= SCRIPT_ENABLE_SCHNORR_MULTISIG;
         flags |= SCRIPT_VERIFY_MINIMALDATA;
     }
 
     if (IsPhononEnabled(consensusparams, pindex)) {
         flags |= SCRIPT_ENFORCE_SIGCHECKS;
     }
 
     // We make sure this node will have replay protection during the next hard
     // fork.
     if (IsReplayProtectionEnabled(consensusparams, pindex)) {
         flags |= SCRIPT_ENABLE_REPLAY_PROTECTION;
     }
 
     return flags;
 }
 
 static int64_t nTimeCheck = 0;
 static int64_t nTimeForks = 0;
 static int64_t nTimeVerify = 0;
 static int64_t nTimeConnect = 0;
 static int64_t nTimeIndex = 0;
 static int64_t nTimeTotal = 0;
 static int64_t nBlocksTotal = 0;
 
 /**
  * Apply the effects of this block (with given index) on the UTXO set
  * represented by coins. Validity checks that depend on the UTXO set are also
  * done; ConnectBlock() can fail if those validity checks fail (among other
  * reasons).
  */
 bool Chainstate::ConnectBlock(const CBlock &block, BlockValidationState &state,
                               CBlockIndex *pindex, CCoinsViewCache &view,
                               BlockValidationOptions options, Amount *blockFees,
                               bool fJustCheck) {
     AssertLockHeld(cs_main);
     assert(pindex);
 
     const BlockHash block_hash{block.GetHash()};
     assert(*pindex->phashBlock == block_hash);
 
     int64_t nTimeStart = GetTimeMicros();
 
     const CChainParams &params{m_chainman.GetParams()};
     const Consensus::Params &consensusParams = params.GetConsensus();
 
     // Check it again in case a previous version let a bad block in
     // NOTE: We don't currently (re-)invoke ContextualCheckBlock() or
     // ContextualCheckBlockHeader() here. This means that if we add a new
     // consensus rule that is enforced in one of those two functions, then we
     // may have let in a block that violates the rule prior to updating the
     // software, and we would NOT be enforcing the rule here. Fully solving
     // upgrade from one software version to the next after a consensus rule
     // change is potentially tricky and issue-specific.
     // Also, currently the rule against blocks more than 2 hours in the future
     // is enforced in ContextualCheckBlockHeader(); we wouldn't want to
     // re-enforce that rule here (at least until we make it impossible for
     // m_adjusted_time_callback() to go backward).
     if (!CheckBlock(block, state, consensusParams,
                     options.withCheckPoW(!fJustCheck)
                         .withCheckMerkleRoot(!fJustCheck))) {
         if (state.GetResult() == BlockValidationResult::BLOCK_MUTATED) {
             // We don't write down blocks to disk if they may have been
             // corrupted, so this should be impossible unless we're having
             // hardware problems.
             return AbortNode(state, "Corrupt block found indicating potential "
                                     "hardware failure; shutting down");
         }
         return error("%s: Consensus::CheckBlock: %s", __func__,
                      state.ToString());
     }
 
     // Verify that the view's current state corresponds to the previous block
     BlockHash hashPrevBlock =
         pindex->pprev == nullptr ? BlockHash() : pindex->pprev->GetBlockHash();
     assert(hashPrevBlock == view.GetBestBlock());
 
     nBlocksTotal++;
 
     // Special case for the genesis block, skipping connection of its
     // transactions (its coinbase is unspendable)
     if (block_hash == consensusParams.hashGenesisBlock) {
         if (!fJustCheck) {
             view.SetBestBlock(pindex->GetBlockHash());
         }
 
         return true;
     }
 
     bool fScriptChecks = true;
     if (!m_chainman.AssumedValidBlock().IsNull()) {
         // We've been configured with the hash of a block which has been
         // externally verified to have a valid history. A suitable default value
         // is included with the software and updated from time to time. Because
         // validity relative to a piece of software is an objective fact these
         // defaults can be easily reviewed. This setting doesn't force the
         // selection of any particular chain but makes validating some faster by
         // effectively caching the result of part of the verification.
         BlockMap::const_iterator it{
             m_blockman.m_block_index.find(m_chainman.AssumedValidBlock())};
         if (it != m_blockman.m_block_index.end()) {
             if (it->second.GetAncestor(pindex->nHeight) == pindex &&
                 m_chainman.m_best_header->GetAncestor(pindex->nHeight) ==
                     pindex &&
                 m_chainman.m_best_header->nChainWork >=
                     m_chainman.MinimumChainWork()) {
                 // This block is a member of the assumed verified chain and an
                 // ancestor of the best header.
                 // Script verification is skipped when connecting blocks under
                 // the assumevalid block. Assuming the assumevalid block is
                 // valid this is safe because block merkle hashes are still
                 // computed and checked, Of course, if an assumed valid block is
                 // invalid due to false scriptSigs this optimization would allow
                 // an invalid chain to be accepted.
                 // The equivalent time check discourages hash power from
                 // extorting the network via DOS attack into accepting an
                 // invalid block through telling users they must manually set
                 // assumevalid. Requiring a software change or burying the
                 // invalid block, regardless of the setting, makes it hard to
                 // hide the implication of the demand. This also avoids having
                 // release candidates that are hardly doing any signature
                 // verification at all in testing without having to artificially
                 // set the default assumed verified block further back. The test
                 // against the minimum chain work prevents the skipping when
                 // denied access to any chain at least as good as the expected
                 // chain.
                 fScriptChecks = (GetBlockProofEquivalentTime(
                                      *m_chainman.m_best_header, *pindex,
                                      *m_chainman.m_best_header,
                                      consensusParams) <= 60 * 60 * 24 * 7 * 2);
             }
         }
     }
 
     int64_t nTime1 = GetTimeMicros();
     nTimeCheck += nTime1 - nTimeStart;
     LogPrint(BCLog::BENCH, "    - Sanity checks: %.2fms [%.2fs (%.2fms/blk)]\n",
              MILLI * (nTime1 - nTimeStart), nTimeCheck * MICRO,
              nTimeCheck * MILLI / nBlocksTotal);
 
     // Do not allow blocks that contain transactions which 'overwrite' older
     // transactions, unless those are already completely spent. If such
     // overwrites are allowed, coinbases and transactions depending upon those
     // can be duplicated to remove the ability to spend the first instance --
     // even after being sent to another address.
     // See BIP30, CVE-2012-1909, and http://r6.ca/blog/20120206T005236Z.html
     // for more information. This rule was originally applied to all blocks
     // with a timestamp after March 15, 2012, 0:00 UTC. Now that the whole
     // chain is irreversibly beyond that time it is applied to all blocks
     // except the two in the chain that violate it. This prevents exploiting
     // the issue against nodes during their initial block download.
     bool fEnforceBIP30 = !((pindex->nHeight == 91842 &&
                             pindex->GetBlockHash() ==
                                 uint256S("0x00000000000a4d0a398161ffc163c503763"
                                          "b1f4360639393e0e4c8e300e0caec")) ||
                            (pindex->nHeight == 91880 &&
                             pindex->GetBlockHash() ==
                                 uint256S("0x00000000000743f190a18c5577a3c2d2a1f"
                                          "610ae9601ac046a38084ccb7cd721")));
 
     // Once BIP34 activated it was not possible to create new duplicate
     // coinbases and thus other than starting with the 2 existing duplicate
     // coinbase pairs, not possible to create overwriting txs. But by the time
     // BIP34 activated, in each of the existing pairs the duplicate coinbase had
     // overwritten the first before the first had been spent. Since those
     // coinbases are sufficiently buried it's no longer possible to create
     // further duplicate transactions descending from the known pairs either. If
     // we're on the known chain at height greater than where BIP34 activated, we
     // can save the db accesses needed for the BIP30 check.
 
     // BIP34 requires that a block at height X (block X) has its coinbase
     // scriptSig start with a CScriptNum of X (indicated height X).  The above
     // logic of no longer requiring BIP30 once BIP34 activates is flawed in the
     // case that there is a block X before the BIP34 height of 227,931 which has
     // an indicated height Y where Y is greater than X.  The coinbase for block
     // X would also be a valid coinbase for block Y, which could be a BIP30
     // violation.  An exhaustive search of all mainnet coinbases before the
     // BIP34 height which have an indicated height greater than the block height
     // reveals many occurrences. The 3 lowest indicated heights found are
     // 209,921, 490,897, and 1,983,702 and thus coinbases for blocks at these 3
     // heights would be the first opportunity for BIP30 to be violated.
 
     // The search reveals a great many blocks which have an indicated height
     // greater than 1,983,702, so we simply remove the optimization to skip
     // BIP30 checking for blocks at height 1,983,702 or higher.  Before we reach
     // that block in another 25 years or so, we should take advantage of a
     // future consensus change to do a new and improved version of BIP34 that
     // will actually prevent ever creating any duplicate coinbases in the
     // future.
     static constexpr int BIP34_IMPLIES_BIP30_LIMIT = 1983702;
 
     // There is no potential to create a duplicate coinbase at block 209,921
     // because this is still before the BIP34 height and so explicit BIP30
     // checking is still active.
 
     // The final case is block 176,684 which has an indicated height of
     // 490,897. Unfortunately, this issue was not discovered until about 2 weeks
     // before block 490,897 so there was not much opportunity to address this
     // case other than to carefully analyze it and determine it would not be a
     // problem. Block 490,897 was, in fact, mined with a different coinbase than
     // block 176,684, but it is important to note that even if it hadn't been or
     // is remined on an alternate fork with a duplicate coinbase, we would still
     // not run into a BIP30 violation.  This is because the coinbase for 176,684
     // is spent in block 185,956 in transaction
     // d4f7fbbf92f4a3014a230b2dc70b8058d02eb36ac06b4a0736d9d60eaa9e8781.  This
     // spending transaction can't be duplicated because it also spends coinbase
     // 0328dd85c331237f18e781d692c92de57649529bd5edf1d01036daea32ffde29.  This
     // coinbase has an indicated height of over 4.2 billion, and wouldn't be
     // duplicatable until that height, and it's currently impossible to create a
     // chain that long. Nevertheless we may wish to consider a future soft fork
     // which retroactively prevents block 490,897 from creating a duplicate
     // coinbase. The two historical BIP30 violations often provide a confusing
     // edge case when manipulating the UTXO and it would be simpler not to have
     // another edge case to deal with.
 
     // testnet3 has no blocks before the BIP34 height with indicated heights
     // post BIP34 before approximately height 486,000,000 and presumably will
     // be reset before it reaches block 1,983,702 and starts doing unnecessary
     // BIP30 checking again.
     assert(pindex->pprev);
     CBlockIndex *pindexBIP34height =
         pindex->pprev->GetAncestor(consensusParams.BIP34Height);
     // Only continue to enforce if we're below BIP34 activation height or the
     // block hash at that height doesn't correspond.
     fEnforceBIP30 =
         fEnforceBIP30 &&
         (!pindexBIP34height ||
          !(pindexBIP34height->GetBlockHash() == consensusParams.BIP34Hash));
 
     // TODO: Remove BIP30 checking from block height 1,983,702 on, once we have
     // a consensus change that ensures coinbases at those heights can not
     // duplicate earlier coinbases.
     if (fEnforceBIP30 || pindex->nHeight >= BIP34_IMPLIES_BIP30_LIMIT) {
         for (const auto &tx : block.vtx) {
             for (size_t o = 0; o < tx->vout.size(); o++) {
                 if (view.HaveCoin(COutPoint(tx->GetId(), o))) {
                     LogPrintf("ERROR: ConnectBlock(): tried to overwrite "
                               "transaction\n");
                     return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                                          "bad-txns-BIP30");
                 }
             }
         }
     }
 
     // Enforce BIP68 (sequence locks).
     int nLockTimeFlags = 0;
     if (DeploymentActiveAt(*pindex, consensusParams,
                            Consensus::DEPLOYMENT_CSV)) {
         nLockTimeFlags |= LOCKTIME_VERIFY_SEQUENCE;
     }
 
     const uint32_t flags = GetNextBlockScriptFlags(pindex->pprev, m_chainman);
 
     int64_t nTime2 = GetTimeMicros();
     nTimeForks += nTime2 - nTime1;
     LogPrint(BCLog::BENCH, "    - Fork checks: %.2fms [%.2fs (%.2fms/blk)]\n",
              MILLI * (nTime2 - nTime1), nTimeForks * MICRO,
              nTimeForks * MILLI / nBlocksTotal);
 
     std::vector<int> prevheights;
     Amount nFees = Amount::zero();
     int nInputs = 0;
 
     // Limit the total executed signature operations in the block, a consensus
     // rule. Tracking during the CPU-consuming part (validation of uncached
     // inputs) is per-input atomic and validation in each thread stops very
     // quickly after the limit is exceeded, so an adversary cannot cause us to
     // exceed the limit by much at all.
     CheckInputsLimiter nSigChecksBlockLimiter(
         GetMaxBlockSigChecksCount(options.getExcessiveBlockSize()));
 
     std::vector<TxSigCheckLimiter> nSigChecksTxLimiters;
     nSigChecksTxLimiters.resize(block.vtx.size() - 1);
 
     CBlockUndo blockundo;
     blockundo.vtxundo.resize(block.vtx.size() - 1);
 
     CCheckQueueControl<CScriptCheck> control(fScriptChecks ? &scriptcheckqueue
                                                            : nullptr);
 
     // Add all outputs
     try {
         for (const auto &ptx : block.vtx) {
             AddCoins(view, *ptx, pindex->nHeight);
         }
     } catch (const std::logic_error &e) {
         // This error will be thrown from AddCoin if we try to connect a block
         // containing duplicate transactions. Such a thing should normally be
         // caught early nowadays (due to ContextualCheckBlock's CTOR
         // enforcement) however some edge cases can escape that:
         // - ContextualCheckBlock does not get re-run after saving the block to
         // disk, and older versions may have saved a weird block.
         // - its checks are not applied to pre-CTOR chains, which we might visit
         // with checkpointing off.
         LogPrintf("ERROR: ConnectBlock(): tried to overwrite transaction\n");
         return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                              "tx-duplicate");
     }
 
     size_t txIndex = 0;
     // nSigChecksRet may be accurate (found in cache) or 0 (checks were
     // deferred into vChecks).
     int nSigChecksRet;
     for (const auto &ptx : block.vtx) {
         const CTransaction &tx = *ptx;
         const bool isCoinBase = tx.IsCoinBase();
         nInputs += tx.vin.size();
 
         {
             Amount txfee = Amount::zero();
             TxValidationState tx_state;
             if (!isCoinBase &&
                 !Consensus::CheckTxInputs(tx, tx_state, view, pindex->nHeight,
                                           txfee)) {
                 // Any transaction validation failure in ConnectBlock is a block
                 // consensus failure.
                 state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                               tx_state.GetRejectReason(),
                               tx_state.GetDebugMessage());
 
                 return error("%s: Consensus::CheckTxInputs: %s, %s", __func__,
                              tx.GetId().ToString(), state.ToString());
             }
             nFees += txfee;
         }
 
         if (!MoneyRange(nFees)) {
             LogPrintf("ERROR: %s: accumulated fee in the block out of range.\n",
                       __func__);
             return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                                  "bad-txns-accumulated-fee-outofrange");
         }
 
         // The following checks do not apply to the coinbase.
         if (isCoinBase) {
             continue;
         }
 
         // Check that transaction is BIP68 final BIP68 lock checks (as
         // opposed to nLockTime checks) must be in ConnectBlock because they
         // require the UTXO set.
         prevheights.resize(tx.vin.size());
         for (size_t j = 0; j < tx.vin.size(); j++) {
             prevheights[j] = view.AccessCoin(tx.vin[j].prevout).GetHeight();
         }
 
         if (!SequenceLocks(tx, nLockTimeFlags, prevheights, *pindex)) {
             LogPrintf("ERROR: %s: contains a non-BIP68-final transaction\n",
                       __func__);
             return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                                  "bad-txns-nonfinal");
         }
 
         // Don't cache results if we're actually connecting blocks (still
         // consult the cache, though).
         bool fCacheResults = fJustCheck;
 
         const bool fEnforceSigCheck = flags & SCRIPT_ENFORCE_SIGCHECKS;
         if (!fEnforceSigCheck) {
             // Historically, there has been transactions with a very high
             // sigcheck count, so we need to disable this check for such
             // transactions.
             nSigChecksTxLimiters[txIndex] = TxSigCheckLimiter::getDisabled();
         }
 
         std::vector<CScriptCheck> vChecks;
         TxValidationState tx_state;
         if (fScriptChecks &&
             !CheckInputScripts(tx, tx_state, view, flags, fCacheResults,
                                fCacheResults, PrecomputedTransactionData(tx),
                                nSigChecksRet, nSigChecksTxLimiters[txIndex],
                                &nSigChecksBlockLimiter, &vChecks)) {
             // Any transaction validation failure in ConnectBlock is a block
             // consensus failure
             state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                           tx_state.GetRejectReason(),
                           tx_state.GetDebugMessage());
             return error(
                 "ConnectBlock(): CheckInputScripts on %s failed with %s",
                 tx.GetId().ToString(), state.ToString());
         }
 
         control.Add(vChecks);
 
         // Note: this must execute in the same iteration as CheckTxInputs (not
         // in a separate loop) in order to detect double spends. However,
         // this does not prevent double-spending by duplicated transaction
         // inputs in the same transaction (cf. CVE-2018-17144) -- that check is
         // done in CheckBlock (CheckRegularTransaction).
         SpendCoins(view, tx, blockundo.vtxundo.at(txIndex), pindex->nHeight);
         txIndex++;
     }
 
     int64_t nTime3 = GetTimeMicros();
     nTimeConnect += nTime3 - nTime2;
     LogPrint(BCLog::BENCH,
              "      - Connect %u transactions: %.2fms (%.3fms/tx, %.3fms/txin) "
              "[%.2fs (%.2fms/blk)]\n",
              (unsigned)block.vtx.size(), MILLI * (nTime3 - nTime2),
              MILLI * (nTime3 - nTime2) / block.vtx.size(),
              nInputs <= 1 ? 0 : MILLI * (nTime3 - nTime2) / (nInputs - 1),
              nTimeConnect * MICRO, nTimeConnect * MILLI / nBlocksTotal);
 
     const Amount blockReward =
         nFees + GetBlockSubsidy(pindex->nHeight, consensusParams);
     if (block.vtx[0]->GetValueOut() > blockReward) {
         LogPrintf("ERROR: ConnectBlock(): coinbase pays too much (actual=%d vs "
                   "limit=%d)\n",
                   block.vtx[0]->GetValueOut(), blockReward);
         return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                              "bad-cb-amount");
     }
 
     if (blockFees) {
         *blockFees = nFees;
     }
 
     if (!control.Wait()) {
         return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                              "blk-bad-inputs", "parallel script check failed");
     }
 
     int64_t nTime4 = GetTimeMicros();
     nTimeVerify += nTime4 - nTime2;
     LogPrint(
         BCLog::BENCH,
         "    - Verify %u txins: %.2fms (%.3fms/txin) [%.2fs (%.2fms/blk)]\n",
         nInputs - 1, MILLI * (nTime4 - nTime2),
         nInputs <= 1 ? 0 : MILLI * (nTime4 - nTime2) / (nInputs - 1),
         nTimeVerify * MICRO, nTimeVerify * MILLI / nBlocksTotal);
 
     if (fJustCheck) {
         return true;
     }
 
     if (!m_blockman.WriteUndoDataForBlock(blockundo, state, pindex, params)) {
         return false;
     }
 
     if (!pindex->IsValid(BlockValidity::SCRIPTS)) {
         pindex->RaiseValidity(BlockValidity::SCRIPTS);
         m_blockman.m_dirty_blockindex.insert(pindex);
     }
 
     assert(pindex->phashBlock);
     // add this block to the view's block chain
     view.SetBestBlock(pindex->GetBlockHash());
 
     int64_t nTime5 = GetTimeMicros();
     nTimeIndex += nTime5 - nTime4;
     LogPrint(BCLog::BENCH, "    - Index writing: %.2fms [%.2fs (%.2fms/blk)]\n",
              MILLI * (nTime5 - nTime4), nTimeIndex * MICRO,
              nTimeIndex * MILLI / nBlocksTotal);
 
     TRACE6(validation, block_connected, block_hash.data(), pindex->nHeight,
            block.vtx.size(), nInputs, nSigChecksRet,
            // in microseconds (µs)
            nTime5 - nTimeStart);
 
     return true;
 }
 
 CoinsCacheSizeState Chainstate::GetCoinsCacheSizeState() {
     AssertLockHeld(::cs_main);
     return this->GetCoinsCacheSizeState(m_coinstip_cache_size_bytes,
                                         m_mempool ? m_mempool->m_max_size_bytes
                                                   : 0);
 }
 
 CoinsCacheSizeState
 Chainstate::GetCoinsCacheSizeState(size_t max_coins_cache_size_bytes,
                                    size_t max_mempool_size_bytes) {
     AssertLockHeld(::cs_main);
     int64_t nMempoolUsage = m_mempool ? m_mempool->DynamicMemoryUsage() : 0;
     int64_t cacheSize = CoinsTip().DynamicMemoryUsage();
     int64_t nTotalSpace =
         max_coins_cache_size_bytes +
         std::max<int64_t>(int64_t(max_mempool_size_bytes) - nMempoolUsage, 0);
 
     //! No need to periodic flush if at least this much space still available.
     static constexpr int64_t MAX_BLOCK_COINSDB_USAGE_BYTES =
         10 * 1024 * 1024; // 10MB
     int64_t large_threshold = std::max(
         (9 * nTotalSpace) / 10, nTotalSpace - MAX_BLOCK_COINSDB_USAGE_BYTES);
 
     if (cacheSize > nTotalSpace) {
         LogPrintf("Cache size (%s) exceeds total space (%s)\n", cacheSize,
                   nTotalSpace);
         return CoinsCacheSizeState::CRITICAL;
     } else if (cacheSize > large_threshold) {
         return CoinsCacheSizeState::LARGE;
     }
     return CoinsCacheSizeState::OK;
 }
 
 bool Chainstate::FlushStateToDisk(BlockValidationState &state,
                                   FlushStateMode mode, int nManualPruneHeight) {
     LOCK(cs_main);
     assert(this->CanFlushToDisk());
     std::set<int> setFilesToPrune;
     bool full_flush_completed = false;
 
     const size_t coins_count = CoinsTip().GetCacheSize();
     const size_t coins_mem_usage = CoinsTip().DynamicMemoryUsage();
 
     try {
         {
             bool fFlushForPrune = false;
             bool fDoFullFlush = false;
 
             CoinsCacheSizeState cache_state = GetCoinsCacheSizeState();
             LOCK(m_blockman.cs_LastBlockFile);
             if (m_blockman.IsPruneMode() &&
                 (m_blockman.m_check_for_pruning || nManualPruneHeight > 0) &&
                 !fReindex) {
                 // Make sure we don't prune above the blockfilterindexes
                 // bestblocks. Pruning is height-based.
                 int last_prune = m_chain.Height();
                 ForEachBlockFilterIndex([&](BlockFilterIndex &index) {
                     last_prune = std::max(
                         1, std::min(last_prune,
                                     index.GetSummary().best_block_height));
                 });
 
                 if (nManualPruneHeight > 0) {
                     LOG_TIME_MILLIS_WITH_CATEGORY(
                         "find files to prune (manual)", BCLog::BENCH);
                     m_blockman.FindFilesToPruneManual(
                         setFilesToPrune,
                         std::min(last_prune, nManualPruneHeight),
                         m_chain.Height());
                 } else {
                     LOG_TIME_MILLIS_WITH_CATEGORY("find files to prune",
                                                   BCLog::BENCH);
                     m_blockman.FindFilesToPrune(
                         setFilesToPrune,
                         m_chainman.GetParams().PruneAfterHeight(),
                         m_chain.Height(), last_prune, IsInitialBlockDownload());
                     m_blockman.m_check_for_pruning = false;
                 }
                 if (!setFilesToPrune.empty()) {
                     fFlushForPrune = true;
                     if (!m_blockman.m_have_pruned) {
                         m_blockman.m_block_tree_db->WriteFlag(
                             "prunedblockfiles", true);
                         m_blockman.m_have_pruned = true;
                     }
                 }
             }
             const auto nNow = GetTime<std::chrono::microseconds>();
             // Avoid writing/flushing immediately after startup.
             if (m_last_write.count() == 0) {
                 m_last_write = nNow;
             }
             if (m_last_flush.count() == 0) {
                 m_last_flush = nNow;
             }
             // The cache is large and we're within 10% and 10 MiB of the limit,
             // but we have time now (not in the middle of a block processing).
             bool fCacheLarge = mode == FlushStateMode::PERIODIC &&
                                cache_state >= CoinsCacheSizeState::LARGE;
             // The cache is over the limit, we have to write now.
             bool fCacheCritical = mode == FlushStateMode::IF_NEEDED &&
                                   cache_state >= CoinsCacheSizeState::CRITICAL;
             // It's been a while since we wrote the block index to disk. Do this
             // frequently, so we don't need to redownload after a crash.
             bool fPeriodicWrite = mode == FlushStateMode::PERIODIC &&
                                   nNow > m_last_write + DATABASE_WRITE_INTERVAL;
             // It's been very long since we flushed the cache. Do this
             // infrequently, to optimize cache usage.
             bool fPeriodicFlush = mode == FlushStateMode::PERIODIC &&
                                   nNow > m_last_flush + DATABASE_FLUSH_INTERVAL;
             // Combine all conditions that result in a full cache flush.
             fDoFullFlush = (mode == FlushStateMode::ALWAYS) || fCacheLarge ||
                            fCacheCritical || fPeriodicFlush || fFlushForPrune;
             // Write blocks and block index to disk.
             if (fDoFullFlush || fPeriodicWrite) {
                 // Ensure we can write block index
                 if (!CheckDiskSpace(gArgs.GetBlocksDirPath())) {
                     return AbortNode(state, "Disk space is too low!",
                                      _("Disk space is too low!"));
                 }
 
                 {
                     LOG_TIME_MILLIS_WITH_CATEGORY(
                         "write block and undo data to disk", BCLog::BENCH);
 
                     // First make sure all block and undo data is flushed to
                     // disk.
                     m_blockman.FlushBlockFile();
                 }
                 // Then update all block file information (which may refer to
                 // block and undo files).
                 {
                     LOG_TIME_MILLIS_WITH_CATEGORY("write block index to disk",
                                                   BCLog::BENCH);
 
                     if (!m_blockman.WriteBlockIndexDB()) {
                         return AbortNode(
                             state, "Failed to write to block index database");
                     }
                 }
 
                 // Finally remove any pruned files
                 if (fFlushForPrune) {
                     LOG_TIME_MILLIS_WITH_CATEGORY("unlink pruned files",
                                                   BCLog::BENCH);
 
                     UnlinkPrunedFiles(setFilesToPrune);
                 }
                 m_last_write = nNow;
             }
             // Flush best chain related state. This can only be done if the
             // blocks / block index write was also done.
             if (fDoFullFlush && !CoinsTip().GetBestBlock().IsNull()) {
                 LOG_TIME_MILLIS_WITH_CATEGORY(
                     strprintf("write coins cache to disk (%d coins, %.2fkB)",
                               coins_count, coins_mem_usage / 1000),
                     BCLog::BENCH);
 
                 // Typical Coin structures on disk are around 48 bytes in size.
                 // Pushing a new one to the database can cause it to be written
                 // twice (once in the log, and once in the tables). This is
                 // already an overestimation, as most will delete an existing
                 // entry or overwrite one. Still, use a conservative safety
                 // factor of 2.
                 if (!CheckDiskSpace(gArgs.GetDataDirNet(),
                                     48 * 2 * 2 * CoinsTip().GetCacheSize())) {
                     return AbortNode(state, "Disk space is too low!",
                                      _("Disk space is too low!"));
                 }
 
                 // Flush the chainstate (which may refer to block index
                 // entries).
                 if (!CoinsTip().Flush()) {
                     return AbortNode(state, "Failed to write to coin database");
                 }
                 m_last_flush = nNow;
                 full_flush_completed = true;
             }
 
             TRACE5(utxocache, flush,
                    // in microseconds (µs)
                    GetTimeMicros() - nNow.count(), uint32_t(mode), coins_count,
                    uint64_t(coins_mem_usage), fFlushForPrune);
         }
 
         if (full_flush_completed) {
             // Update best block in wallet (so we can detect restored wallets).
             GetMainSignals().ChainStateFlushed(m_chain.GetLocator());
         }
     } catch (const std::runtime_error &e) {
         return AbortNode(state, std::string("System error while flushing: ") +
                                     e.what());
     }
     return true;
 }
 
 void Chainstate::ForceFlushStateToDisk() {
     BlockValidationState state;
     if (!this->FlushStateToDisk(state, FlushStateMode::ALWAYS)) {
         LogPrintf("%s: failed to flush state (%s)\n", __func__,
                   state.ToString());
     }
 }
 
 void Chainstate::PruneAndFlush() {
     BlockValidationState state;
     m_blockman.m_check_for_pruning = true;
     if (!this->FlushStateToDisk(state, FlushStateMode::NONE)) {
         LogPrintf("%s: failed to flush state (%s)\n", __func__,
                   state.ToString());
     }
 }
 
 static void UpdateTipLog(const CCoinsViewCache &coins_tip,
                          const CBlockIndex *tip, const CChainParams &params,
                          const std::string &func_name,
                          const std::string &prefix)
     EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {
     AssertLockHeld(::cs_main);
     LogPrintf("%s%s: new best=%s height=%d version=0x%08x log2_work=%f tx=%ld "
               "date='%s' progress=%f cache=%.1fMiB(%utxo)\n",
               prefix, func_name, tip->GetBlockHash().ToString(), tip->nHeight,
               tip->nVersion, log(tip->nChainWork.getdouble()) / log(2.0),
               tip->GetChainTxCount(),
               FormatISO8601DateTime(tip->GetBlockTime()),
               GuessVerificationProgress(params.TxData(), tip),
               coins_tip.DynamicMemoryUsage() * (1.0 / (1 << 20)),
               coins_tip.GetCacheSize());
 }
 
 void Chainstate::UpdateTip(const CBlockIndex *pindexNew) {
     AssertLockHeld(::cs_main);
     const auto &coins_tip = CoinsTip();
 
     const CChainParams &params{m_chainman.GetParams()};
 
     // The remainder of the function isn't relevant if we are not acting on
     // the active chainstate, so return if need be.
     if (this != &m_chainman.ActiveChainstate()) {
         // Only log every so often so that we don't bury log messages at the
         // tip.
         constexpr int BACKGROUND_LOG_INTERVAL = 2000;
         if (pindexNew->nHeight % BACKGROUND_LOG_INTERVAL == 0) {
             UpdateTipLog(coins_tip, pindexNew, params, __func__,
                          "[background validation] ");
         }
         return;
     }
 
     // New best block
     if (m_mempool) {
         m_mempool->AddTransactionsUpdated(1);
     }
 
     {
         LOCK(g_best_block_mutex);
         g_best_block = pindexNew->GetBlockHash();
         g_best_block_cv.notify_all();
     }
 
     UpdateTipLog(coins_tip, pindexNew, params, __func__, "");
 }
 
 /**
  * Disconnect m_chain's tip.
  * After calling, the mempool will be in an inconsistent state, with
  * transactions from disconnected blocks being added to disconnectpool. You
  * should make the mempool consistent again by calling updateMempoolForReorg.
  * with cs_main held.
  *
  * If disconnectpool is nullptr, then no disconnected transactions are added to
  * disconnectpool (note that the caller is responsible for mempool consistency
  * in any case).
  */
 bool Chainstate::DisconnectTip(BlockValidationState &state,
                                DisconnectedBlockTransactions *disconnectpool) {
     AssertLockHeld(cs_main);
     if (m_mempool) {
         AssertLockHeld(m_mempool->cs);
     }
 
     CBlockIndex *pindexDelete = m_chain.Tip();
     const Consensus::Params &consensusParams = m_chainman.GetConsensus();
 
     assert(pindexDelete);
 
     // Read block from disk.
     std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>();
     CBlock &block = *pblock;
     if (!ReadBlockFromDisk(block, pindexDelete, consensusParams)) {
         return error("DisconnectTip(): Failed to read block");
     }
 
     // Apply the block atomically to the chain state.
     int64_t nStart = GetTimeMicros();
     {
         CCoinsViewCache view(&CoinsTip());
         assert(view.GetBestBlock() == pindexDelete->GetBlockHash());
         if (DisconnectBlock(block, pindexDelete, view) !=
             DisconnectResult::OK) {
             return error("DisconnectTip(): DisconnectBlock %s failed",
                          pindexDelete->GetBlockHash().ToString());
         }
 
         bool flushed = view.Flush();
         assert(flushed);
     }
 
     LogPrint(BCLog::BENCH, "- Disconnect block: %.2fms\n",
              (GetTimeMicros() - nStart) * MILLI);
 
     // Write the chain state to disk, if necessary.
     if (!FlushStateToDisk(state, FlushStateMode::IF_NEEDED)) {
         return false;
     }
 
     if (m_mempool) {
         // If this block is deactivating a fork, we move all mempool
         // transactions in front of disconnectpool for reprocessing in a future
         // updateMempoolForReorg call
         if (pindexDelete->pprev != nullptr &&
             GetNextBlockScriptFlags(pindexDelete, m_chainman) !=
                 GetNextBlockScriptFlags(pindexDelete->pprev, m_chainman)) {
             LogPrint(BCLog::MEMPOOL,
                      "Disconnecting mempool due to rewind of upgrade block\n");
             if (disconnectpool) {
                 disconnectpool->importMempool(*m_mempool);
             }
             m_mempool->clear();
         }
 
         if (disconnectpool) {
             disconnectpool->addForBlock(block.vtx, *m_mempool);
         }
     }
 
     m_chain.SetTip(pindexDelete->pprev);
 
     UpdateTip(pindexDelete->pprev);
     // Let wallets know transactions went from 1-confirmed to
     // 0-confirmed or conflicted:
     GetMainSignals().BlockDisconnected(pblock, pindexDelete);
     return true;
 }
 
 static int64_t nTimeReadFromDisk = 0;
 static int64_t nTimeConnectTotal = 0;
 static int64_t nTimeFlush = 0;
 static int64_t nTimeChainState = 0;
 static int64_t nTimePostConnect = 0;
 
 struct PerBlockConnectTrace {
     CBlockIndex *pindex = nullptr;
     std::shared_ptr<const CBlock> pblock;
     PerBlockConnectTrace() {}
 };
 
 /**
  * Used to track blocks whose transactions were applied to the UTXO state as a
  * part of a single ActivateBestChainStep call.
  *
  * This class is single-use, once you call GetBlocksConnected() you have to
  * throw it away and make a new one.
  */
 class ConnectTrace {
 private:
     std::vector<PerBlockConnectTrace> blocksConnected;
 
 public:
     explicit ConnectTrace() : blocksConnected(1) {}
 
     void BlockConnected(CBlockIndex *pindex,
                         std::shared_ptr<const CBlock> pblock) {
         assert(!blocksConnected.back().pindex);
         assert(pindex);
         assert(pblock);
         blocksConnected.back().pindex = pindex;
         blocksConnected.back().pblock = std::move(pblock);
         blocksConnected.emplace_back();
     }
 
     std::vector<PerBlockConnectTrace> &GetBlocksConnected() {
         // We always keep one extra block at the end of our list because blocks
         // are added after all the conflicted transactions have been filled in.
         // Thus, the last entry should always be an empty one waiting for the
         // transactions from the next block. We pop the last entry here to make
         // sure the list we return is sane.
         assert(!blocksConnected.back().pindex);
         blocksConnected.pop_back();
         return blocksConnected;
     }
 };
 
 /**
  * Connect a new block to m_chain. pblock is either nullptr or a pointer to
  * a CBlock corresponding to pindexNew, to bypass loading it again from disk.
  *
  * The block is added to connectTrace if connection succeeds.
  */
 bool Chainstate::ConnectTip(BlockValidationState &state,
                             BlockPolicyValidationState &blockPolicyState,
                             CBlockIndex *pindexNew,
                             const std::shared_ptr<const CBlock> &pblock,
                             ConnectTrace &connectTrace,
                             DisconnectedBlockTransactions &disconnectpool) {
     AssertLockHeld(cs_main);
     if (m_mempool) {
         AssertLockHeld(m_mempool->cs);
     }
 
     const Consensus::Params &consensusParams = m_chainman.GetConsensus();
 
     assert(pindexNew->pprev == m_chain.Tip());
     // Read block from disk.
     int64_t nTime1 = GetTimeMicros();
     std::shared_ptr<const CBlock> pthisBlock;
     if (!pblock) {
         std::shared_ptr<CBlock> pblockNew = std::make_shared<CBlock>();
         if (!ReadBlockFromDisk(*pblockNew, pindexNew, consensusParams)) {
             return AbortNode(state, "Failed to read block");
         }
         pthisBlock = pblockNew;
     } else {
         pthisBlock = pblock;
     }
 
     const CBlock &blockConnecting = *pthisBlock;
 
     // Apply the block atomically to the chain state.
     int64_t nTime2 = GetTimeMicros();
     nTimeReadFromDisk += nTime2 - nTime1;
     int64_t nTime3;
     LogPrint(BCLog::BENCH, "  - Load block from disk: %.2fms [%.2fs]\n",
              (nTime2 - nTime1) * MILLI, nTimeReadFromDisk * MICRO);
     {
         Amount blockFees{Amount::zero()};
         CCoinsViewCache view(&CoinsTip());
         bool rv = ConnectBlock(blockConnecting, state, pindexNew, view,
                                BlockValidationOptions(m_chainman.GetConfig()),
                                &blockFees);
         GetMainSignals().BlockChecked(blockConnecting, state);
         if (!rv) {
             if (state.IsInvalid()) {
                 InvalidBlockFound(pindexNew, state);
             }
 
             return error("%s: ConnectBlock %s failed, %s", __func__,
                          pindexNew->GetBlockHash().ToString(),
                          state.ToString());
         }
 
         /**
          * The block is valid by consensus rules so now we check if the block
          * passes all block policy checks. If not, then park the block and bail.
          *
          * We check block parking policies before flushing changes to the UTXO
          * set. This allows us to avoid rewinding everything immediately after.
          *
          * Only check block parking policies the first time the block is
          * connected. Avalanche voting can override the parking decision made by
          * these policies.
          */
         const BlockHash blockhash = pindexNew->GetBlockHash();
         if (!IsInitialBlockDownload() &&
             !m_filterParkingPoliciesApplied.contains(blockhash)) {
             m_filterParkingPoliciesApplied.insert(blockhash);
 
             const Amount blockReward =
                 blockFees +
                 GetBlockSubsidy(pindexNew->nHeight, consensusParams);
 
             std::vector<std::unique_ptr<ParkingPolicy>> parkingPolicies;
             parkingPolicies.emplace_back(std::make_unique<MinerFundPolicy>(
                 consensusParams, *pindexNew, blockConnecting, blockReward));
 
             if (g_avalanche) {
                 parkingPolicies.emplace_back(
                     std::make_unique<StakingRewardsPolicy>(
                         consensusParams, *pindexNew, blockConnecting,
                         blockReward));
 
                 if (m_mempool) {
                     parkingPolicies.emplace_back(
                         std::make_unique<PreConsensusPolicy>(
                             *pindexNew, blockConnecting, m_mempool));
                 }
             }
 
             // If any block policy is violated, bail on the first one found
             if (std::find_if_not(parkingPolicies.begin(), parkingPolicies.end(),
                                  [&](const auto &policy) {
                                      bool ret = (*policy)(blockPolicyState);
                                      if (!ret) {
                                          LogPrintf(
                                              "Park block because it "
                                              "violated a block policy: %s\n",
                                              blockPolicyState.ToString());
                                      }
                                      return ret;
                                  }) != parkingPolicies.end()) {
                 pindexNew->nStatus = pindexNew->nStatus.withParked();
                 m_blockman.m_dirty_blockindex.insert(pindexNew);
                 return false;
             }
         }
 
         nTime3 = GetTimeMicros();
         nTimeConnectTotal += nTime3 - nTime2;
         assert(nBlocksTotal > 0);
         LogPrint(BCLog::BENCH,
                  "  - Connect total: %.2fms [%.2fs (%.2fms/blk)]\n",
                  (nTime3 - nTime2) * MILLI, nTimeConnectTotal * MICRO,
                  nTimeConnectTotal * MILLI / nBlocksTotal);
         bool flushed = view.Flush();
         assert(flushed);
     }
 
     int64_t nTime4 = GetTimeMicros();
     nTimeFlush += nTime4 - nTime3;
     LogPrint(BCLog::BENCH, "  - Flush: %.2fms [%.2fs (%.2fms/blk)]\n",
              (nTime4 - nTime3) * MILLI, nTimeFlush * MICRO,
              nTimeFlush * MILLI / nBlocksTotal);
 
     // Write the chain state to disk, if necessary.
     if (!FlushStateToDisk(state, FlushStateMode::IF_NEEDED)) {
         return false;
     }
 
     int64_t nTime5 = GetTimeMicros();
     nTimeChainState += nTime5 - nTime4;
     LogPrint(BCLog::BENCH,
              "  - Writing chainstate: %.2fms [%.2fs (%.2fms/blk)]\n",
              (nTime5 - nTime4) * MILLI, nTimeChainState * MICRO,
              nTimeChainState * MILLI / nBlocksTotal);
 
     // Remove conflicting transactions from the mempool;
     if (m_mempool) {
         disconnectpool.removeForBlock(blockConnecting.vtx, *m_mempool);
 
         // If this block is activating a fork, we move all mempool transactions
         // in front of disconnectpool for reprocessing in a future
         // updateMempoolForReorg call
         if (pindexNew->pprev != nullptr &&
             GetNextBlockScriptFlags(pindexNew, m_chainman) !=
                 GetNextBlockScriptFlags(pindexNew->pprev, m_chainman)) {
             LogPrint(
                 BCLog::MEMPOOL,
                 "Disconnecting mempool due to acceptance of upgrade block\n");
             disconnectpool.importMempool(*m_mempool);
         }
     }
 
     // Update m_chain & related variables.
     m_chain.SetTip(pindexNew);
     UpdateTip(pindexNew);
 
     int64_t nTime6 = GetTimeMicros();
     nTimePostConnect += nTime6 - nTime5;
     nTimeTotal += nTime6 - nTime1;
     LogPrint(BCLog::BENCH,
              "  - Connect postprocess: %.2fms [%.2fs (%.2fms/blk)]\n",
              (nTime6 - nTime5) * MILLI, nTimePostConnect * MICRO,
              nTimePostConnect * MILLI / nBlocksTotal);
     LogPrint(BCLog::BENCH, "- Connect block: %.2fms [%.2fs (%.2fms/blk)]\n",
              (nTime6 - nTime1) * MILLI, nTimeTotal * MICRO,
              nTimeTotal * MILLI / nBlocksTotal);
 
     // If we are the background validation chainstate, check to see if we are
     // done validating the snapshot (i.e. our tip has reached the snapshot's
     // base block).
     if (this != &m_chainman.ActiveChainstate()) {
         // This call may set `m_disabled`, which is referenced immediately
         // afterwards in ActivateBestChain, so that we stop connecting blocks
         // past the snapshot base.
         m_chainman.MaybeCompleteSnapshotValidation();
     }
 
     connectTrace.BlockConnected(pindexNew, std::move(pthisBlock));
     return true;
 }
 
 /**
  * Return the tip of the chain with the most work in it, that isn't known to be
  * invalid (it's however far from certain to be valid).
  */
 CBlockIndex *Chainstate::FindMostWorkChain(
     std::vector<const CBlockIndex *> &blocksToReconcile) {
     AssertLockHeld(::cs_main);
     do {
         CBlockIndex *pindexNew = nullptr;
 
         // Find the best candidate header.
         {
             std::set<CBlockIndex *, CBlockIndexWorkComparator>::reverse_iterator
                 it = setBlockIndexCandidates.rbegin();
             if (it == setBlockIndexCandidates.rend()) {
                 return nullptr;
             }
             pindexNew = *it;
         }
 
         // If this block will cause an avalanche finalized block to be reorged,
         // then we park it.
         {
             LOCK(cs_avalancheFinalizedBlockIndex);
             if (m_avalancheFinalizedBlockIndex &&
                 !AreOnTheSameFork(pindexNew, m_avalancheFinalizedBlockIndex)) {
                 LogPrintf("Park block %s because it forks prior to the "
                           "avalanche finalized chaintip.\n",
                           pindexNew->GetBlockHash().ToString());
                 pindexNew->nStatus = pindexNew->nStatus.withParked();
                 m_blockman.m_dirty_blockindex.insert(pindexNew);
             }
         }
 
         const bool fAvalancheEnabled = isAvalancheEnabled(gArgs);
         const bool fAutoUnpark =
             gArgs.GetBoolArg("-automaticunparking", !fAvalancheEnabled);
 
         const CBlockIndex *pindexFork = m_chain.FindFork(pindexNew);
 
         // Check whether all blocks on the path between the currently active
         // chain and the candidate are valid. Just going until the active chain
         // is an optimization, as we know all blocks in it are valid already.
         CBlockIndex *pindexTest = pindexNew;
         bool hasValidAncestor = true;
         while (hasValidAncestor && pindexTest && pindexTest != pindexFork) {
             assert(pindexTest->HaveTxsDownloaded() || pindexTest->nHeight == 0);
 
             // If this is a parked chain, but it has enough PoW, clear the park
             // state.
             bool fParkedChain = pindexTest->nStatus.isOnParkedChain();
             if (fAutoUnpark && fParkedChain) {
                 const CBlockIndex *pindexTip = m_chain.Tip();
 
                 // During initialization, pindexTip and/or pindexFork may be
                 // null. In this case, we just ignore the fact that the chain is
                 // parked.
                 if (!pindexTip || !pindexFork) {
                     UnparkBlock(pindexTest);
                     continue;
                 }
 
                 // A parked chain can be unparked if it has twice as much PoW
                 // accumulated as the main chain has since the fork block.
                 CBlockIndex const *pindexExtraPow = pindexTip;
                 arith_uint256 requiredWork = pindexTip->nChainWork;
                 switch (pindexTip->nHeight - pindexFork->nHeight) {
                     // Limit the penality for depth 1, 2 and 3 to half a block
                     // worth of work to ensure we don't fork accidentally.
                     case 3:
                     case 2:
                         pindexExtraPow = pindexExtraPow->pprev;
                     // FALLTHROUGH
                     case 1: {
                         const arith_uint256 deltaWork =
                             pindexExtraPow->nChainWork - pindexFork->nChainWork;
                         requiredWork += (deltaWork >> 1);
                         break;
                     }
                     default:
                         requiredWork +=
                             pindexExtraPow->nChainWork - pindexFork->nChainWork;
                         break;
                 }
 
                 if (pindexNew->nChainWork > requiredWork) {
                     // We have enough, clear the parked state.
                     LogPrintf("Unpark chain up to block %s as it has "
                               "accumulated enough PoW.\n",
                               pindexNew->GetBlockHash().ToString());
                     fParkedChain = false;
                     UnparkBlock(pindexTest);
                 }
             }
 
             // Pruned nodes may have entries in setBlockIndexCandidates for
             // which block files have been deleted. Remove those as candidates
             // for the most work chain if we come across them; we can't switch
             // to a chain unless we have all the non-active-chain parent blocks.
             bool fInvalidChain = pindexTest->nStatus.isInvalid();
             bool fMissingData = !pindexTest->nStatus.hasData();
             if (!(fInvalidChain || fParkedChain || fMissingData)) {
                 // The current block is acceptable, move to the parent, up to
                 // the fork point.
                 pindexTest = pindexTest->pprev;
                 continue;
             }
 
             // Candidate chain is not usable (either invalid or parked or
             // missing data)
             hasValidAncestor = false;
             setBlockIndexCandidates.erase(pindexTest);
 
             if (fInvalidChain && (m_chainman.m_best_invalid == nullptr ||
                                   pindexNew->nChainWork >
                                       m_chainman.m_best_invalid->nChainWork)) {
                 m_chainman.m_best_invalid = pindexNew;
             }
 
             if (fParkedChain && (m_chainman.m_best_parked == nullptr ||
                                  pindexNew->nChainWork >
                                      m_chainman.m_best_parked->nChainWork)) {
                 m_chainman.m_best_parked = pindexNew;
             }
 
             LogPrintf("Considered switching to better tip %s but that chain "
                       "contains a%s%s%s block.\n",
                       pindexNew->GetBlockHash().ToString(),
                       fInvalidChain ? "n invalid" : "",
                       fParkedChain ? " parked" : "",
                       fMissingData ? " missing-data" : "");
 
             CBlockIndex *pindexFailed = pindexNew;
             // Remove the entire chain from the set.
             while (pindexTest != pindexFailed) {
                 if (fInvalidChain || fParkedChain) {
                     pindexFailed->nStatus =
                         pindexFailed->nStatus.withFailedParent(fInvalidChain)
                             .withParkedParent(fParkedChain);
                 } else if (fMissingData) {
                     // If we're missing data, then add back to
                     // m_blocks_unlinked, so that if the block arrives in the
                     // future we can try adding to setBlockIndexCandidates
                     // again.
                     m_blockman.m_blocks_unlinked.insert(
                         std::make_pair(pindexFailed->pprev, pindexFailed));
                 }
                 setBlockIndexCandidates.erase(pindexFailed);
                 pindexFailed = pindexFailed->pprev;
             }
 
             if (fInvalidChain || fParkedChain) {
                 // We discovered a new chain tip that is either parked or
                 // invalid, we may want to warn.
                 CheckForkWarningConditionsOnNewFork(pindexNew);
             }
         }
 
         if (fAvalancheEnabled && g_avalanche) {
             blocksToReconcile.push_back(pindexNew);
         }
 
         // We found a candidate that has valid ancestors. This is our guy.
         if (hasValidAncestor) {
             return pindexNew;
         }
     } while (true);
 }
 
 /**
  * Delete all entries in setBlockIndexCandidates that are worse than the current
  * tip.
  */
 void Chainstate::PruneBlockIndexCandidates() {
     // Note that we can't delete the current block itself, as we may need to
     // return to it later in case a reorganization to a better block fails.
     auto it = setBlockIndexCandidates.begin();
     while (it != setBlockIndexCandidates.end() &&
            setBlockIndexCandidates.value_comp()(*it, m_chain.Tip())) {
         setBlockIndexCandidates.erase(it++);
     }
 
     // Either the current tip or a successor of it we're working towards is left
     // in setBlockIndexCandidates.
     assert(!setBlockIndexCandidates.empty());
 }
 
 /**
  * Try to make some progress towards making pindexMostWork the active block.
  * pblock is either nullptr or a pointer to a CBlock corresponding to
  * pindexMostWork.
  *
  * @returns true unless a system error occurred
  */
 bool Chainstate::ActivateBestChainStep(
     BlockValidationState &state, CBlockIndex *pindexMostWork,
     const std::shared_ptr<const CBlock> &pblock, bool &fInvalidFound,
     ConnectTrace &connectTrace) {
     AssertLockHeld(cs_main);
     if (m_mempool) {
         AssertLockHeld(m_mempool->cs);
     }
 
     const CBlockIndex *pindexOldTip = m_chain.Tip();
     const CBlockIndex *pindexFork = m_chain.FindFork(pindexMostWork);
 
     // Disconnect active blocks which are no longer in the best chain.
     bool fBlocksDisconnected = false;
     DisconnectedBlockTransactions disconnectpool;
     while (m_chain.Tip() && m_chain.Tip() != pindexFork) {
         if (!fBlocksDisconnected) {
             // Import and clear mempool; we must do this to preserve
             // topological ordering in the mempool index. This is ok since
             // inserts into the mempool are very fast now in our new
             // implementation.
             disconnectpool.importMempool(*m_mempool);
         }
 
         if (!DisconnectTip(state, &disconnectpool)) {
             // This is likely a fatal error, but keep the mempool consistent,
             // just in case. Only remove from the mempool in this case.
             if (m_mempool) {
                 disconnectpool.updateMempoolForReorg(*this, false, *m_mempool);
             }
 
             // If we're unable to disconnect a block during normal operation,
             // then that is a failure of our local system -- we should abort
             // rather than stay on a less work chain.
             AbortNode(state,
                       "Failed to disconnect block; see debug.log for details");
             return false;
         }
 
         fBlocksDisconnected = true;
     }
 
     // Build list of new blocks to connect.
     std::vector<CBlockIndex *> vpindexToConnect;
     bool fContinue = true;
     int nHeight = pindexFork ? pindexFork->nHeight : -1;
     while (fContinue && nHeight != pindexMostWork->nHeight) {
         // Don't iterate the entire list of potential improvements toward the
         // best tip, as we likely only need a few blocks along the way.
         int nTargetHeight = std::min(nHeight + 32, pindexMostWork->nHeight);
         vpindexToConnect.clear();
         vpindexToConnect.reserve(nTargetHeight - nHeight);
         CBlockIndex *pindexIter = pindexMostWork->GetAncestor(nTargetHeight);
         while (pindexIter && pindexIter->nHeight != nHeight) {
             vpindexToConnect.push_back(pindexIter);
             pindexIter = pindexIter->pprev;
         }
 
         nHeight = nTargetHeight;
 
         // Connect new blocks.
         for (CBlockIndex *pindexConnect : reverse_iterate(vpindexToConnect)) {
             BlockPolicyValidationState blockPolicyState;
             if (!ConnectTip(state, blockPolicyState, pindexConnect,
                             pindexConnect == pindexMostWork
                                 ? pblock
                                 : std::shared_ptr<const CBlock>(),
                             connectTrace, disconnectpool)) {
                 if (state.IsInvalid()) {
                     // The block violates a consensus rule.
                     if (state.GetResult() !=
                         BlockValidationResult::BLOCK_MUTATED) {
                         InvalidChainFound(vpindexToConnect.back());
                     }
                     state = BlockValidationState();
                     fInvalidFound = true;
                     fContinue = false;
                     break;
                 }
 
                 if (blockPolicyState.IsInvalid()) {
                     // The block violates a policy rule.
                     fContinue = false;
                     break;
                 }
 
                 // A system error occurred (disk space, database error, ...).
                 // Make the mempool consistent with the current tip, just in
                 // case any observers try to use it before shutdown.
                 if (m_mempool) {
                     disconnectpool.updateMempoolForReorg(*this, false,
                                                          *m_mempool);
                 }
                 return false;
             } else {
                 PruneBlockIndexCandidates();
                 if (!pindexOldTip ||
                     m_chain.Tip()->nChainWork > pindexOldTip->nChainWork) {
                     // We're in a better position than we were. Return
                     // temporarily to release the lock.
                     fContinue = false;
                     break;
                 }
             }
         }
     }
 
     if (m_mempool) {
         if (fBlocksDisconnected || !disconnectpool.isEmpty()) {
             // If any blocks were disconnected, we need to update the mempool
             // even if disconnectpool is empty. The disconnectpool may also be
             // non-empty if the mempool was imported due to new validation rules
             // being in effect.
             LogPrint(BCLog::MEMPOOL,
                      "Updating mempool due to reorganization or "
                      "rules upgrade/downgrade\n");
             disconnectpool.updateMempoolForReorg(*this, true, *m_mempool);
         }
 
         m_mempool->check(this->CoinsTip(), this->m_chain.Height() + 1);
     }
 
     // Callbacks/notifications for a new best chain.
     if (fInvalidFound) {
         CheckForkWarningConditionsOnNewFork(pindexMostWork);
     } else {
         CheckForkWarningConditions();
     }
 
     return true;
 }
 
 static SynchronizationState GetSynchronizationState(bool init) {
     if (!init) {
         return SynchronizationState::POST_INIT;
     }
     if (::fReindex) {
         return SynchronizationState::INIT_REINDEX;
     }
     return SynchronizationState::INIT_DOWNLOAD;
 }
 
 static bool NotifyHeaderTip(Chainstate &chainstate) LOCKS_EXCLUDED(cs_main) {
     bool fNotify = false;
     bool fInitialBlockDownload = false;
     static CBlockIndex *pindexHeaderOld = nullptr;
     CBlockIndex *pindexHeader = nullptr;
     {
         LOCK(cs_main);
         pindexHeader = chainstate.m_chainman.m_best_header;
 
         if (pindexHeader != pindexHeaderOld) {
             fNotify = true;
             fInitialBlockDownload = chainstate.IsInitialBlockDownload();
             pindexHeaderOld = pindexHeader;
         }
     }
 
     // Send block tip changed notifications without cs_main
     if (fNotify) {
         uiInterface.NotifyHeaderTip(
             GetSynchronizationState(fInitialBlockDownload),
             pindexHeader->nHeight, pindexHeader->nTime, false);
     }
     return fNotify;
 }
 
 static void LimitValidationInterfaceQueue() LOCKS_EXCLUDED(cs_main) {
     AssertLockNotHeld(cs_main);
 
     if (GetMainSignals().CallbacksPending() > 10) {
         SyncWithValidationInterfaceQueue();
     }
 }
 
 bool Chainstate::ActivateBestChain(BlockValidationState &state,
                                    std::shared_ptr<const CBlock> pblock,
                                    bool skip_checkblockindex) {
     AssertLockNotHeld(m_chainstate_mutex);
 
     // Note that while we're often called here from ProcessNewBlock, this is
     // far from a guarantee. Things in the P2P/RPC will often end up calling
     // us in the middle of ProcessNewBlock - do not assume pblock is set
     // sanely for performance or correctness!
     AssertLockNotHeld(::cs_main);
 
     // ABC maintains a fair degree of expensive-to-calculate internal state
     // because this function periodically releases cs_main so that it does not
     // lock up other threads for too long during large connects - and to allow
     // for e.g. the callback queue to drain we use m_chainstate_mutex to enforce
     // mutual exclusion so that only one caller may execute this function at a
     // time
     LOCK(m_chainstate_mutex);
 
     // Belt-and-suspenders check that we aren't attempting to advance the
     // background chainstate past the snapshot base block.
     if (WITH_LOCK(::cs_main, return m_disabled)) {
         LogPrintf("m_disabled is set - this chainstate should not be in "
                   "operation. Please report this as a bug. %s\n",
                   PACKAGE_BUGREPORT);
         return false;
     }
 
     CBlockIndex *pindexMostWork = nullptr;
     CBlockIndex *pindexNewTip = nullptr;
     int nStopAtHeight = gArgs.GetIntArg("-stopatheight", DEFAULT_STOPATHEIGHT);
     do {
         // Block until the validation queue drains. This should largely
         // never happen in normal operation, however may happen during
         // reindex, causing memory blowup if we run too far ahead.
         // Note that if a validationinterface callback ends up calling
         // ActivateBestChain this may lead to a deadlock! We should
         // probably have a DEBUG_LOCKORDER test for this in the future.
         LimitValidationInterfaceQueue();
 
         std::vector<const CBlockIndex *> blocksToReconcile;
         bool blocks_connected = false;
 
         {
             LOCK(cs_main);
             // Lock transaction pool for at least as long as it takes for
             // connectTrace to be consumed
             LOCK(MempoolMutex());
             CBlockIndex *starting_tip = m_chain.Tip();
             do {
                 // We absolutely may not unlock cs_main until we've made forward
                 // progress (with the exception of shutdown due to hardware
                 // issues, low disk space, etc).
 
                 // Destructed before cs_main is unlocked
                 ConnectTrace connectTrace;
 
                 if (pindexMostWork == nullptr) {
                     pindexMostWork = FindMostWorkChain(blocksToReconcile);
                 }
 
                 // Whether we have anything to do at all.
                 if (pindexMostWork == nullptr ||
                     pindexMostWork == m_chain.Tip()) {
                     break;
                 }
 
                 bool fInvalidFound = false;
                 std::shared_ptr<const CBlock> nullBlockPtr;
                 if (!ActivateBestChainStep(
                         state, pindexMostWork,
                         pblock && pblock->GetHash() ==
                                       pindexMostWork->GetBlockHash()
                             ? pblock
                             : nullBlockPtr,
                         fInvalidFound, connectTrace)) {
                     // A system error occurred
                     return false;
                 }
                 blocks_connected = true;
 
                 if (fInvalidFound ||
                     (pindexMostWork && pindexMostWork->nStatus.isParked())) {
                     // Wipe cache, we may need another branch now.
                     pindexMostWork = nullptr;
                 }
 
                 pindexNewTip = m_chain.Tip();
                 for (const PerBlockConnectTrace &trace :
                      connectTrace.GetBlocksConnected()) {
                     assert(trace.pblock && trace.pindex);
                     GetMainSignals().BlockConnected(trace.pblock, trace.pindex);
                 }
 
                 // This will have been toggled in
                 // ActivateBestChainStep -> ConnectTip ->
                 // MaybeCompleteSnapshotValidation, if at all, so we should
                 // catch it here.
                 //
                 // Break this do-while to ensure we don't advance past the base
                 // snapshot.
                 if (m_disabled) {
                     break;
                 }
             } while (!m_chain.Tip() ||
                      (starting_tip && CBlockIndexWorkComparator()(
                                           m_chain.Tip(), starting_tip)));
 
             // Check the index once we're done with the above loop, since
             // we're going to release cs_main soon. If the index is in a bad
             // state now, then it's better to know immediately rather than
             // randomly have it cause a problem in a race.
             if (!skip_checkblockindex) {
                 CheckBlockIndex();
             }
 
             if (blocks_connected) {
                 const CBlockIndex *pindexFork = m_chain.FindFork(starting_tip);
                 bool fInitialDownload = IsInitialBlockDownload();
 
                 // Notify external listeners about the new tip.
                 // Enqueue while holding cs_main to ensure that UpdatedBlockTip
                 // is called in the order in which blocks are connected
                 if (pindexFork != pindexNewTip) {
                     // Notify ValidationInterface subscribers
                     GetMainSignals().UpdatedBlockTip(pindexNewTip, pindexFork,
                                                      fInitialDownload);
 
                     // Always notify the UI if a new block tip was connected
                     uiInterface.NotifyBlockTip(
                         GetSynchronizationState(fInitialDownload),
                         pindexNewTip);
                 }
             }
         }
         // When we reach this point, we switched to a new tip (stored in
         // pindexNewTip).
         if (g_avalanche) {
             for (const CBlockIndex *pindex : blocksToReconcile) {
                 g_avalanche->addToReconcile(pindex);
                 g_avalanche->computeStakingReward(pindex);
             }
         }
 
         if (!blocks_connected) {
             return true;
         }
 
         if (nStopAtHeight && pindexNewTip &&
             pindexNewTip->nHeight >= nStopAtHeight) {
             StartShutdown();
         }
 
         if (WITH_LOCK(::cs_main, return m_disabled)) {
             // Background chainstate has reached the snapshot base block, so
             // exit.
             break;
         }
 
         // We check shutdown only after giving ActivateBestChainStep a chance to
         // run once so that we never shutdown before connecting the genesis
         // block during LoadChainTip(). Previously this caused an assert()
         // failure during shutdown in such cases as the UTXO DB flushing checks
         // that the best block hash is non-null.
         if (ShutdownRequested()) {
             break;
         }
     } while (pindexNewTip != pindexMostWork);
 
     // Write changes periodically to disk, after relay.
     if (!FlushStateToDisk(state, FlushStateMode::PERIODIC)) {
         return false;
     }
 
     return true;
 }
 
 bool Chainstate::PreciousBlock(BlockValidationState &state,
                                CBlockIndex *pindex) {
     AssertLockNotHeld(m_chainstate_mutex);
     AssertLockNotHeld(::cs_main);
     {
         LOCK(cs_main);
         if (pindex->nChainWork < m_chain.Tip()->nChainWork) {
             // Nothing to do, this block is not at the tip.
             return true;
         }
 
         if (m_chain.Tip()->nChainWork > nLastPreciousChainwork) {
             // The chain has been extended since the last call, reset the
             // counter.
             nBlockReverseSequenceId = -1;
         }
 
         nLastPreciousChainwork = m_chain.Tip()->nChainWork;
         setBlockIndexCandidates.erase(pindex);
         pindex->nSequenceId = nBlockReverseSequenceId;
         if (nBlockReverseSequenceId > std::numeric_limits<int32_t>::min()) {
             // We can't keep reducing the counter if somebody really wants to
             // call preciousblock 2**31-1 times on the same set of tips...
             nBlockReverseSequenceId--;
         }
 
         // In case this was parked, unpark it.
         UnparkBlock(pindex);
 
         // Make sure it is added to the candidate list if appropriate.
         if (pindex->IsValid(BlockValidity::TRANSACTIONS) &&
             pindex->HaveTxsDownloaded()) {
             setBlockIndexCandidates.insert(pindex);
             PruneBlockIndexCandidates();
         }
     }
 
     return ActivateBestChain(state);
 }
 
 namespace {
 // Leverage RAII to run a functor at scope end
 template <typename Func> struct Defer {
     Func func;
     Defer(Func &&f) : func(std::move(f)) {}
     ~Defer() { func(); }
 };
 } // namespace
 
 bool Chainstate::UnwindBlock(BlockValidationState &state, CBlockIndex *pindex,
                              bool invalidate) {
     // Genesis block can't be invalidated or parked
     assert(pindex);
     if (pindex->nHeight == 0) {
         return false;
     }
 
     CBlockIndex *to_mark_failed_or_parked = pindex;
     bool pindex_was_in_chain = false;
     int disconnected = 0;
 
     // We do not allow ActivateBestChain() to run while UnwindBlock() is
     // running, as that could cause the tip to change while we disconnect
     // blocks. (Note for backport of Core PR16849: we acquire
     // LOCK(m_chainstate_mutex) in the Park, Invalidate and FinalizeBlock
     // functions due to differences in our code)
     AssertLockHeld(m_chainstate_mutex);
 
     // We'll be acquiring and releasing cs_main below, to allow the validation
     // callbacks to run. However, we should keep the block index in a
     // consistent state as we disconnect blocks -- in particular we need to
     // add equal-work blocks to setBlockIndexCandidates as we disconnect.
     // To avoid walking the block index repeatedly in search of candidates,
     // build a map once so that we can look up candidate blocks by chain
     // work as we go.
     std::multimap<const arith_uint256, CBlockIndex *> candidate_blocks_by_work;
 
     {
         LOCK(cs_main);
         for (auto &entry : m_blockman.m_block_index) {
             CBlockIndex *candidate = &entry.second;
             // We don't need to put anything in our active chain into the
             // multimap, because those candidates will be found and considered
             // as we disconnect.
             // Instead, consider only non-active-chain blocks that have at
             // least as much work as where we expect the new tip to end up.
             if (!m_chain.Contains(candidate) &&
                 !CBlockIndexWorkComparator()(candidate, pindex->pprev) &&
                 candidate->IsValid(BlockValidity::TRANSACTIONS) &&
                 candidate->HaveTxsDownloaded()) {
                 candidate_blocks_by_work.insert(
                     std::make_pair(candidate->nChainWork, candidate));
             }
         }
     }
 
     {
         LOCK(cs_main);
         // Lock for as long as disconnectpool is in scope to make sure
         // UpdateMempoolForReorg is called after DisconnectTip without unlocking
         // in between
         LOCK(MempoolMutex());
 
         constexpr int maxDisconnectPoolBlocks = 10;
         bool ret = false;
         DisconnectedBlockTransactions disconnectpool;
         // After 10 blocks this becomes nullptr, so that DisconnectTip will
         // stop giving us unwound block txs if we are doing a deep unwind.
         DisconnectedBlockTransactions *optDisconnectPool = &disconnectpool;
 
         // Disable thread safety analysis because we can't require m_mempool->cs
         // as m_mempool can be null. We keep the runtime analysis though.
         Defer deferred([&]() NO_THREAD_SAFETY_ANALYSIS {
             AssertLockHeld(cs_main);
             if (m_mempool && !disconnectpool.isEmpty()) {
                 AssertLockHeld(m_mempool->cs);
                 // DisconnectTip will add transactions to disconnectpool.
                 // When all unwinding is done and we are on a new tip, we must
                 // add all transactions back to the mempool against the new tip.
                 disconnectpool.updateMempoolForReorg(*this,
                                                      /* fAddToMempool = */ ret,
                                                      *m_mempool);
             }
         });
 
         // Disconnect (descendants of) pindex, and mark them invalid.
         while (true) {
             if (ShutdownRequested()) {
                 break;
             }
 
             // Make sure the queue of validation callbacks doesn't grow
             // unboundedly.
             // FIXME this commented code is a regression and could cause OOM if
             // a very old block is invalidated via the invalidateblock RPC.
             // This can be uncommented if the main signals are moved away from
             // cs_main or this code is refactored so that cs_main can be
             // released at this point.
             //
             // LimitValidationInterfaceQueue();
 
             if (!m_chain.Contains(pindex)) {
                 break;
             }
 
             if (m_mempool && disconnected == 0) {
                 // On first iteration, we grab all the mempool txs to preserve
                 // topological ordering. This has the side-effect of temporarily
                 // clearing the mempool, but we will re-add later in
                 // updateMempoolForReorg() (above). This technique guarantees
                 // mempool consistency as well as ensures that our topological
                 // entry_id index is always correct.
                 disconnectpool.importMempool(*m_mempool);
             }
 
             pindex_was_in_chain = true;
             CBlockIndex *invalid_walk_tip = m_chain.Tip();
 
             // ActivateBestChain considers blocks already in m_chain
             // unconditionally valid already, so force disconnect away from it.
 
             ret = DisconnectTip(state, optDisconnectPool);
             ++disconnected;
 
             if (optDisconnectPool && disconnected > maxDisconnectPoolBlocks) {
                 // Stop using the disconnect pool after 10 blocks. After 10
                 // blocks we no longer add block tx's to the disconnectpool.
                 // However, when this scope ends we will reconcile what's
                 // in the pool with the new tip (in the deferred d'tor above).
                 optDisconnectPool = nullptr;
             }
 
             if (!ret) {
                 return false;
             }
 
             assert(invalid_walk_tip->pprev == m_chain.Tip());
 
             // We immediately mark the disconnected blocks as invalid.
             // This prevents a case where pruned nodes may fail to
             // invalidateblock and be left unable to start as they have no tip
             // candidates (as there are no blocks that meet the "have data and
             // are not invalid per nStatus" criteria for inclusion in
             // setBlockIndexCandidates).
 
             invalid_walk_tip->nStatus =
                 invalidate ? invalid_walk_tip->nStatus.withFailed()
                            : invalid_walk_tip->nStatus.withParked();
 
             m_blockman.m_dirty_blockindex.insert(invalid_walk_tip);
             setBlockIndexCandidates.insert(invalid_walk_tip->pprev);
 
             if (invalid_walk_tip == to_mark_failed_or_parked->pprev &&
                 (invalidate ? to_mark_failed_or_parked->nStatus.hasFailed()
                             : to_mark_failed_or_parked->nStatus.isParked())) {
                 // We only want to mark the last disconnected block as
                 // Failed (or Parked); its children need to be FailedParent (or
                 // ParkedParent) instead.
                 to_mark_failed_or_parked->nStatus =
                     (invalidate
                          ? to_mark_failed_or_parked->nStatus.withFailed(false)
                                .withFailedParent()
                          : to_mark_failed_or_parked->nStatus.withParked(false)
                                .withParkedParent());
 
                 m_blockman.m_dirty_blockindex.insert(to_mark_failed_or_parked);
             }
 
             // Add any equal or more work headers to setBlockIndexCandidates
             auto candidate_it = candidate_blocks_by_work.lower_bound(
                 invalid_walk_tip->pprev->nChainWork);
             while (candidate_it != candidate_blocks_by_work.end()) {
                 if (!CBlockIndexWorkComparator()(candidate_it->second,
                                                  invalid_walk_tip->pprev)) {
                     setBlockIndexCandidates.insert(candidate_it->second);
                     candidate_it = candidate_blocks_by_work.erase(candidate_it);
                 } else {
                     ++candidate_it;
                 }
             }
 
             // Track the last disconnected block, so we can correct its
             // FailedParent (or ParkedParent) status in future iterations, or,
             // if it's the last one, call InvalidChainFound on it.
             to_mark_failed_or_parked = invalid_walk_tip;
         }
     }
 
     CheckBlockIndex();
 
     {
         LOCK(cs_main);
         if (m_chain.Contains(to_mark_failed_or_parked)) {
             // If the to-be-marked invalid block is in the active chain,
             // something is interfering and we can't proceed.
             return false;
         }
 
         // Mark pindex (or the last disconnected block) as invalid (or parked),
         // even when it never was in the main chain.
         to_mark_failed_or_parked->nStatus =
             invalidate ? to_mark_failed_or_parked->nStatus.withFailed()
                        : to_mark_failed_or_parked->nStatus.withParked();
         m_blockman.m_dirty_blockindex.insert(to_mark_failed_or_parked);
         if (invalidate) {
             m_chainman.m_failed_blocks.insert(to_mark_failed_or_parked);
         }
 
         // If any new blocks somehow arrived while we were disconnecting
         // (above), then the pre-calculation of what should go into
         // setBlockIndexCandidates may have missed entries. This would
         // technically be an inconsistency in the block index, but if we clean
         // it up here, this should be an essentially unobservable error.
         // Loop back over all block index entries and add any missing entries
         // to setBlockIndexCandidates.
         for (auto &[_, block_index] : m_blockman.m_block_index) {
             if (block_index.IsValid(BlockValidity::TRANSACTIONS) &&
                 block_index.HaveTxsDownloaded() &&
                 !setBlockIndexCandidates.value_comp()(&block_index,
                                                       m_chain.Tip())) {
                 setBlockIndexCandidates.insert(&block_index);
             }
         }
 
         if (invalidate) {
             InvalidChainFound(to_mark_failed_or_parked);
         }
     }
 
     // Only notify about a new block tip if the active chain was modified.
     if (pindex_was_in_chain) {
         uiInterface.NotifyBlockTip(
             GetSynchronizationState(IsInitialBlockDownload()),
             to_mark_failed_or_parked->pprev);
     }
     return true;
 }
 
 bool Chainstate::InvalidateBlock(BlockValidationState &state,
                                  CBlockIndex *pindex) {
     AssertLockNotHeld(m_chainstate_mutex);
     AssertLockNotHeld(::cs_main);
     // See 'Note for backport of Core PR16849' in Chainstate::UnwindBlock
     LOCK(m_chainstate_mutex);
 
     return UnwindBlock(state, pindex, true);
 }
 
 bool Chainstate::ParkBlock(BlockValidationState &state, CBlockIndex *pindex) {
     AssertLockNotHeld(m_chainstate_mutex);
     AssertLockNotHeld(::cs_main);
     // See 'Note for backport of Core PR16849' in Chainstate::UnwindBlock
     LOCK(m_chainstate_mutex);
 
     return UnwindBlock(state, pindex, false);
 }
 
 template <typename F>
 bool Chainstate::UpdateFlagsForBlock(CBlockIndex *pindexBase,
                                      CBlockIndex *pindex, F f) {
     BlockStatus newStatus = f(pindex->nStatus);
     if (pindex->nStatus != newStatus &&
         (!pindexBase ||
          pindex->GetAncestor(pindexBase->nHeight) == pindexBase)) {
         pindex->nStatus = newStatus;
         m_blockman.m_dirty_blockindex.insert(pindex);
         if (newStatus.isValid()) {
             m_chainman.m_failed_blocks.erase(pindex);
         }
 
         if (pindex->IsValid(BlockValidity::TRANSACTIONS) &&
             pindex->HaveTxsDownloaded() &&
             setBlockIndexCandidates.value_comp()(m_chain.Tip(), pindex)) {
             setBlockIndexCandidates.insert(pindex);
         }
         return true;
     }
     return false;
 }
 
 template <typename F, typename C, typename AC>
 void Chainstate::UpdateFlags(CBlockIndex *pindex, CBlockIndex *&pindexReset,
                              F f, C fChild, AC fAncestorWasChanged) {
     AssertLockHeld(cs_main);
 
     // Update the current block and ancestors; while we're doing this, identify
     // which was the deepest ancestor we changed.
     CBlockIndex *pindexDeepestChanged = pindex;
     for (auto pindexAncestor = pindex; pindexAncestor != nullptr;
          pindexAncestor = pindexAncestor->pprev) {
         if (UpdateFlagsForBlock(nullptr, pindexAncestor, f)) {
             pindexDeepestChanged = pindexAncestor;
         }
     }
 
     if (pindexReset &&
         pindexReset->GetAncestor(pindexDeepestChanged->nHeight) ==
             pindexDeepestChanged) {
         // reset pindexReset if it had a modified ancestor.
         pindexReset = nullptr;
     }
 
     // Update all blocks under modified blocks.
     for (auto &[_, block_index] : m_blockman.m_block_index) {
         UpdateFlagsForBlock(pindex, &block_index, fChild);
         UpdateFlagsForBlock(pindexDeepestChanged, &block_index,
                             fAncestorWasChanged);
     }
 }
 
 void Chainstate::ResetBlockFailureFlags(CBlockIndex *pindex) {
     AssertLockHeld(cs_main);
 
     UpdateFlags(
         pindex, m_chainman.m_best_invalid,
         [](const BlockStatus status) {
             return status.withClearedFailureFlags();
         },
         [](const BlockStatus status) {
             return status.withClearedFailureFlags();
         },
         [](const BlockStatus status) {
             return status.withFailedParent(false);
         });
 }
 
 void Chainstate::UnparkBlockImpl(CBlockIndex *pindex, bool fClearChildren) {
     AssertLockHeld(cs_main);
 
     UpdateFlags(
         pindex, m_chainman.m_best_parked,
         [](const BlockStatus status) {
             return status.withClearedParkedFlags();
         },
         [fClearChildren](const BlockStatus status) {
             return fClearChildren ? status.withClearedParkedFlags()
                                   : status.withParkedParent(false);
         },
         [](const BlockStatus status) {
             return status.withParkedParent(false);
         });
 }
 
 void Chainstate::UnparkBlockAndChildren(CBlockIndex *pindex) {
     return UnparkBlockImpl(pindex, true);
 }
 
 void Chainstate::UnparkBlock(CBlockIndex *pindex) {
     return UnparkBlockImpl(pindex, false);
 }
 
 bool Chainstate::AvalancheFinalizeBlock(CBlockIndex *pindex) {
     if (!pindex) {
         return false;
     }
 
     if (!m_chain.Contains(pindex)) {
         LogPrint(BCLog::AVALANCHE,
                  "The block to mark finalized by avalanche is not on the "
                  "active chain: %s\n",
                  pindex->GetBlockHash().ToString());
         return false;
     }
 
     if (g_avalanche) {
         g_avalanche->cleanupStakingRewards(pindex->nHeight);
     }
 
     if (IsBlockAvalancheFinalized(pindex)) {
         return true;
     }
 
     {
         LOCK(cs_avalancheFinalizedBlockIndex);
         m_avalancheFinalizedBlockIndex = pindex;
     }
 
     GetMainSignals().BlockFinalized(pindex);
 
     return true;
 }
 
 void Chainstate::ClearAvalancheFinalizedBlock() {
     LOCK(cs_avalancheFinalizedBlockIndex);
     m_avalancheFinalizedBlockIndex = nullptr;
 }
 
 bool Chainstate::IsBlockAvalancheFinalized(const CBlockIndex *pindex) const {
     LOCK(cs_avalancheFinalizedBlockIndex);
     return pindex && m_avalancheFinalizedBlockIndex &&
            m_avalancheFinalizedBlockIndex->GetAncestor(pindex->nHeight) ==
                pindex;
 }
 
 /**
  * Mark a block as having its data received and checked (up to
  * BLOCK_VALID_TRANSACTIONS).
  */
 void Chainstate::ReceivedBlockTransactions(const CBlock &block,
                                            CBlockIndex *pindexNew,
                                            const FlatFilePos &pos) {
     pindexNew->nTx = block.vtx.size();
     pindexNew->nSize = ::GetSerializeSize(block, PROTOCOL_VERSION);
     pindexNew->nFile = pos.nFile;
     pindexNew->nDataPos = pos.nPos;
     pindexNew->nUndoPos = 0;
     pindexNew->nStatus = pindexNew->nStatus.withData();
     pindexNew->RaiseValidity(BlockValidity::TRANSACTIONS);
     m_blockman.m_dirty_blockindex.insert(pindexNew);
 
     if (pindexNew->UpdateChainStats()) {
         // If pindexNew is the genesis block or all parents are
         // BLOCK_VALID_TRANSACTIONS.
         std::deque<CBlockIndex *> queue;
         queue.push_back(pindexNew);
 
         // Recursively process any descendant blocks that now may be eligible to
         // be connected.
         while (!queue.empty()) {
             CBlockIndex *pindex = queue.front();
             queue.pop_front();
             pindex->UpdateChainStats();
             if (pindex->nSequenceId == 0) {
                 // We assign a sequence is when transaction are received to
                 // prevent a miner from being able to broadcast a block but not
                 // its content. However, a sequence id may have been set
                 // manually, for instance via PreciousBlock, in which case, we
                 // don't need to assign one.
                 pindex->nSequenceId = nBlockSequenceId++;
             }
 
             if (m_chain.Tip() == nullptr ||
                 !setBlockIndexCandidates.value_comp()(pindex, m_chain.Tip())) {
                 setBlockIndexCandidates.insert(pindex);
             }
 
             std::pair<std::multimap<CBlockIndex *, CBlockIndex *>::iterator,
                       std::multimap<CBlockIndex *, CBlockIndex *>::iterator>
                 range = m_blockman.m_blocks_unlinked.equal_range(pindex);
             while (range.first != range.second) {
                 std::multimap<CBlockIndex *, CBlockIndex *>::iterator it =
                     range.first;
                 queue.push_back(it->second);
                 range.first++;
                 m_blockman.m_blocks_unlinked.erase(it);
             }
         }
     } else if (pindexNew->pprev &&
                pindexNew->pprev->IsValid(BlockValidity::TREE)) {
         m_blockman.m_blocks_unlinked.insert(
             std::make_pair(pindexNew->pprev, pindexNew));
     }
 }
 
 /**
  * Return true if the provided block header is valid.
  * Only verify PoW if blockValidationOptions is configured to do so.
  * This allows validation of headers on which the PoW hasn't been done.
  * For example: to validate template handed to mining software.
  * Do not call this for any check that depends on the context.
  * For context-dependent calls, see ContextualCheckBlockHeader.
  */
 static bool CheckBlockHeader(const CBlockHeader &block,
                              BlockValidationState &state,
                              const Consensus::Params &params,
                              BlockValidationOptions validationOptions) {
     // Check proof of work matches claimed amount
     if (validationOptions.shouldValidatePoW() &&
         !CheckProofOfWork(block.GetHash(), block.nBits, params)) {
         return state.Invalid(BlockValidationResult::BLOCK_INVALID_HEADER,
                              "high-hash", "proof of work failed");
     }
 
     return true;
 }
 
 bool CheckBlock(const CBlock &block, BlockValidationState &state,
                 const Consensus::Params &params,
                 BlockValidationOptions validationOptions) {
     // These are checks that are independent of context.
     if (block.fChecked) {
         return true;
     }
 
     // Check that the header is valid (particularly PoW).  This is mostly
     // redundant with the call in AcceptBlockHeader.
     if (!CheckBlockHeader(block, state, params, validationOptions)) {
         return false;
     }
 
     // Check the merkle root.
     if (validationOptions.shouldValidateMerkleRoot()) {
         bool mutated;
         uint256 hashMerkleRoot2 = BlockMerkleRoot(block, &mutated);
         if (block.hashMerkleRoot != hashMerkleRoot2) {
             return state.Invalid(BlockValidationResult::BLOCK_MUTATED,
                                  "bad-txnmrklroot", "hashMerkleRoot mismatch");
         }
 
         // Check for merkle tree malleability (CVE-2012-2459): repeating
         // sequences of transactions in a block without affecting the merkle
         // root of a block, while still invalidating it.
         if (mutated) {
             return state.Invalid(BlockValidationResult::BLOCK_MUTATED,
                                  "bad-txns-duplicate", "duplicate transaction");
         }
     }
 
     // All potential-corruption validation must be done before we do any
     // transaction validation, as otherwise we may mark the header as invalid
     // because we receive the wrong transactions for it.
 
     // First transaction must be coinbase.
     if (block.vtx.empty()) {
         return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                              "bad-cb-missing", "first tx is not coinbase");
     }
 
     // Size limits.
     auto nMaxBlockSize = validationOptions.getExcessiveBlockSize();
 
     // Bail early if there is no way this block is of reasonable size.
     if ((block.vtx.size() * MIN_TRANSACTION_SIZE) > nMaxBlockSize) {
         return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                              "bad-blk-length", "size limits failed");
     }
 
     auto currentBlockSize = ::GetSerializeSize(block, PROTOCOL_VERSION);
     if (currentBlockSize > nMaxBlockSize) {
         return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                              "bad-blk-length", "size limits failed");
     }
 
     // And a valid coinbase.
     TxValidationState tx_state;
     if (!CheckCoinbase(*block.vtx[0], tx_state)) {
         return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                              tx_state.GetRejectReason(),
                              strprintf("Coinbase check failed (txid %s) %s",
                                        block.vtx[0]->GetId().ToString(),
                                        tx_state.GetDebugMessage()));
     }
 
     // Check transactions for regularity, skipping the first. Note that this
     // is the first time we check that all after the first are !IsCoinBase.
     for (size_t i = 1; i < block.vtx.size(); i++) {
         auto *tx = block.vtx[i].get();
         if (!CheckRegularTransaction(*tx, tx_state)) {
             return state.Invalid(
                 BlockValidationResult::BLOCK_CONSENSUS,
                 tx_state.GetRejectReason(),
                 strprintf("Transaction check failed (txid %s) %s",
                           tx->GetId().ToString(), tx_state.GetDebugMessage()));
         }
     }
 
     if (validationOptions.shouldValidatePoW() &&
         validationOptions.shouldValidateMerkleRoot()) {
         block.fChecked = true;
     }
 
     return true;
 }
 
 bool HasValidProofOfWork(const std::vector<CBlockHeader> &headers,
                          const Consensus::Params &consensusParams) {
     return std::all_of(headers.cbegin(), headers.cend(),
                        [&](const auto &header) {
                            return CheckProofOfWork(
                                header.GetHash(), header.nBits, consensusParams);
                        });
 }
 
 arith_uint256 CalculateHeadersWork(const std::vector<CBlockHeader> &headers) {
     arith_uint256 total_work{0};
     for (const CBlockHeader &header : headers) {
         CBlockIndex dummy(header);
         total_work += GetBlockProof(dummy);
     }
     return total_work;
 }
 
 /**
  * Context-dependent validity checks.
  * By "context", we mean only the previous block headers, but not the UTXO
  * set; UTXO-related validity checks are done in ConnectBlock().
  * NOTE: This function is not currently invoked by ConnectBlock(), so we
  * should consider upgrade issues if we change which consensus rules are
  * enforced in this function (eg by adding a new consensus rule). See comment
  * in ConnectBlock().
  * Note that -reindex-chainstate skips the validation that happens here!
  */
-static bool ContextualCheckBlockHeader(const CBlockHeader &block,
-                                       BlockValidationState &state,
-                                       BlockManager &blockman,
-                                       ChainstateManager &chainman,
-                                       const CBlockIndex *pindexPrev,
-                                       NodeClock::time_point now)
+static bool ContextualCheckBlockHeader(
+    const CBlockHeader &block, BlockValidationState &state,
+    BlockManager &blockman, ChainstateManager &chainman,
+    const CBlockIndex *pindexPrev, NodeClock::time_point now,
+    const std::optional<CCheckpointData> &test_checkpoints = std::nullopt)
     EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {
     AssertLockHeld(::cs_main);
     assert(pindexPrev != nullptr);
     const int nHeight = pindexPrev->nHeight + 1;
 
     const CChainParams &params = chainman.GetParams();
 
     // Check proof of work
     if (block.nBits != GetNextWorkRequired(pindexPrev, &block, params)) {
         LogPrintf("bad bits after height: %d\n", pindexPrev->nHeight);
         return state.Invalid(BlockValidationResult::BLOCK_INVALID_HEADER,
                              "bad-diffbits", "incorrect proof of work");
     }
 
     // Check against checkpoints
     if (chainman.m_options.checkpoints_enabled) {
-        const CCheckpointData &checkpoints = params.Checkpoints();
+        const CCheckpointData &checkpoints =
+            test_checkpoints ? test_checkpoints.value() : params.Checkpoints();
 
         // Check that the block chain matches the known block chain up to a
         // checkpoint.
         if (!Checkpoints::CheckBlock(checkpoints, nHeight, block.GetHash())) {
             LogPrint(BCLog::VALIDATION,
                      "ERROR: %s: rejected by checkpoint lock-in at %d\n",
                      __func__, nHeight);
             return state.Invalid(BlockValidationResult::BLOCK_CHECKPOINT,
                                  "checkpoint mismatch");
         }
 
         // Don't accept any forks from the main chain prior to last checkpoint.
         // GetLastCheckpoint finds the last checkpoint in MapCheckpoints that's
         // in our BlockIndex().
 
         const CBlockIndex *pcheckpoint =
             blockman.GetLastCheckpoint(checkpoints);
         if (pcheckpoint && nHeight < pcheckpoint->nHeight) {
             LogPrint(BCLog::VALIDATION,
                      "ERROR: %s: forked chain older than last checkpoint "
                      "(height %d)\n",
                      __func__, nHeight);
             return state.Invalid(BlockValidationResult::BLOCK_CHECKPOINT,
                                  "bad-fork-prior-to-checkpoint");
         }
     }
 
     // Check timestamp against prev
     if (block.GetBlockTime() <= pindexPrev->GetMedianTimePast()) {
         return state.Invalid(BlockValidationResult::BLOCK_INVALID_HEADER,
                              "time-too-old", "block's timestamp is too early");
     }
 
     // Check timestamp
     if (block.Time() > now + std::chrono::seconds{MAX_FUTURE_BLOCK_TIME}) {
         return state.Invalid(BlockValidationResult::BLOCK_TIME_FUTURE,
                              "time-too-new",
                              "block timestamp too far in the future");
     }
 
     // Reject blocks with outdated version
     if ((block.nVersion < 2 &&
          DeploymentActiveAfter(pindexPrev, chainman,
                                Consensus::DEPLOYMENT_HEIGHTINCB)) ||
         (block.nVersion < 3 &&
          DeploymentActiveAfter(pindexPrev, chainman,
                                Consensus::DEPLOYMENT_DERSIG)) ||
         (block.nVersion < 4 &&
          DeploymentActiveAfter(pindexPrev, chainman,
                                Consensus::DEPLOYMENT_CLTV))) {
         return state.Invalid(
             BlockValidationResult::BLOCK_INVALID_HEADER,
             strprintf("bad-version(0x%08x)", block.nVersion),
             strprintf("rejected nVersion=0x%08x block", block.nVersion));
     }
 
     return true;
 }
 
 bool ContextualCheckTransactionForCurrentBlock(
     const CBlockIndex *active_chain_tip, const Consensus::Params &params,
     const CTransaction &tx, TxValidationState &state) {
     AssertLockHeld(cs_main);
     // TODO: Make active_chain_tip a reference
     assert(active_chain_tip);
 
     // ContextualCheckTransactionForCurrentBlock() uses
     // active_chain_tip.Height()+1 to evaluate nLockTime because when
     // IsFinalTx() is called within AcceptBlock(), the height of the
     // block *being* evaluated is what is used. Thus if we want to know if a
     // transaction can be part of the *next* block, we need to call
     // ContextualCheckTransaction() with one more than
     // active_chain_tip.Height().
     const int nBlockHeight = active_chain_tip->nHeight + 1;
 
     // BIP113 will require that time-locked transactions have nLockTime set to
     // less than the median time of the previous block they're contained in.
     // When the next block is created its previous block will be the current
     // chain tip, so we use that to calculate the median time passed to
     // ContextualCheckTransaction().
     // This time can also be used for consensus upgrades.
     const int64_t nMedianTimePast{active_chain_tip->GetMedianTimePast()};
 
     return ContextualCheckTransaction(params, tx, state, nBlockHeight,
                                       nMedianTimePast);
 }
 
 /**
  * NOTE: This function is not currently invoked by ConnectBlock(), so we
  * should consider upgrade issues if we change which consensus rules are
  * enforced in this function (eg by adding a new consensus rule). See comment
  * in ConnectBlock().
  * Note that -reindex-chainstate skips the validation that happens here!
  */
 static bool ContextualCheckBlock(const CBlock &block,
                                  BlockValidationState &state,
                                  const ChainstateManager &chainman,
                                  const CBlockIndex *pindexPrev) {
     const int nHeight = pindexPrev == nullptr ? 0 : pindexPrev->nHeight + 1;
 
     // Enforce BIP113 (Median Time Past).
     bool enforce_locktime_median_time_past{false};
     if (DeploymentActiveAfter(pindexPrev, chainman,
                               Consensus::DEPLOYMENT_CSV)) {
         assert(pindexPrev != nullptr);
         enforce_locktime_median_time_past = true;
     }
 
     const int64_t nMedianTimePast =
         pindexPrev == nullptr ? 0 : pindexPrev->GetMedianTimePast();
 
     const int64_t nLockTimeCutoff{enforce_locktime_median_time_past
                                       ? nMedianTimePast
                                       : block.GetBlockTime()};
 
     const Consensus::Params params = chainman.GetConsensus();
     const bool fIsMagneticAnomalyEnabled =
         IsMagneticAnomalyEnabled(params, pindexPrev);
 
     // Check transactions:
     // - canonical ordering
     // - ensure they are finalized
     // - check they have the minimum size
     const CTransaction *prevTx = nullptr;
     for (const auto &ptx : block.vtx) {
         const CTransaction &tx = *ptx;
         if (fIsMagneticAnomalyEnabled) {
             if (prevTx && (tx.GetId() <= prevTx->GetId())) {
                 if (tx.GetId() == prevTx->GetId()) {
                     return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                                          "tx-duplicate",
                                          strprintf("Duplicated transaction %s",
                                                    tx.GetId().ToString()));
                 }
 
                 return state.Invalid(
                     BlockValidationResult::BLOCK_CONSENSUS, "tx-ordering",
                     strprintf("Transaction order is invalid (%s < %s)",
                               tx.GetId().ToString(),
                               prevTx->GetId().ToString()));
             }
 
             if (prevTx || !tx.IsCoinBase()) {
                 prevTx = &tx;
             }
         }
 
         TxValidationState tx_state;
         if (!ContextualCheckTransaction(params, tx, tx_state, nHeight,
                                         nLockTimeCutoff)) {
             return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                                  tx_state.GetRejectReason(),
                                  tx_state.GetDebugMessage());
         }
     }
 
     // Enforce rule that the coinbase starts with serialized block height
     if (DeploymentActiveAfter(pindexPrev, chainman,
                               Consensus::DEPLOYMENT_HEIGHTINCB)) {
         CScript expect = CScript() << nHeight;
         if (block.vtx[0]->vin[0].scriptSig.size() < expect.size() ||
             !std::equal(expect.begin(), expect.end(),
                         block.vtx[0]->vin[0].scriptSig.begin())) {
             return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
                                  "bad-cb-height",
                                  "block height mismatch in coinbase");
         }
     }
 
     return true;
 }
 
 /**
  * If the provided block header is valid, add it to the block index.
  *
  * Returns true if the block is successfully added to the block index.
  */
-bool ChainstateManager::AcceptBlockHeader(const CBlockHeader &block,
-                                          BlockValidationState &state,
-                                          CBlockIndex **ppindex,
-                                          bool min_pow_checked) {
+bool ChainstateManager::AcceptBlockHeader(
+    const CBlockHeader &block, BlockValidationState &state,
+    CBlockIndex **ppindex, bool min_pow_checked,
+    const std::optional<CCheckpointData> &test_checkpoints) {
     AssertLockHeld(cs_main);
     const Config &config = this->GetConfig();
     const CChainParams &chainparams = config.GetChainParams();
 
     // Check for duplicate
     BlockHash hash = block.GetHash();
     BlockMap::iterator miSelf{m_blockman.m_block_index.find(hash)};
     if (hash != chainparams.GetConsensus().hashGenesisBlock) {
         if (miSelf != m_blockman.m_block_index.end()) {
             // Block header is already known.
             CBlockIndex *pindex = &(miSelf->second);
             if (ppindex) {
                 *ppindex = pindex;
             }
 
             if (pindex->nStatus.isInvalid()) {
                 LogPrint(BCLog::VALIDATION, "%s: block %s is marked invalid\n",
                          __func__, hash.ToString());
                 return state.Invalid(
                     BlockValidationResult::BLOCK_CACHED_INVALID, "duplicate");
             }
 
             return true;
         }
 
         if (!CheckBlockHeader(block, state, chainparams.GetConsensus(),
                               BlockValidationOptions(config))) {
             LogPrint(BCLog::VALIDATION,
                      "%s: Consensus::CheckBlockHeader: %s, %s\n", __func__,
                      hash.ToString(), state.ToString());
             return false;
         }
 
         // Get prev block index
         BlockMap::iterator mi{
             m_blockman.m_block_index.find(block.hashPrevBlock)};
         if (mi == m_blockman.m_block_index.end()) {
             LogPrint(BCLog::VALIDATION,
                      "header %s has prev block not found: %s\n",
                      hash.ToString(), block.hashPrevBlock.ToString());
             return state.Invalid(BlockValidationResult::BLOCK_MISSING_PREV,
                                  "prev-blk-not-found");
         }
 
         CBlockIndex *pindexPrev = &((*mi).second);
         assert(pindexPrev);
         if (pindexPrev->nStatus.isInvalid()) {
             LogPrint(BCLog::VALIDATION,
                      "header %s has prev block invalid: %s\n", hash.ToString(),
                      block.hashPrevBlock.ToString());
             return state.Invalid(BlockValidationResult::BLOCK_INVALID_PREV,
                                  "bad-prevblk");
         }
 
-        if (!ContextualCheckBlockHeader(block, state, m_blockman, *this,
-                                        pindexPrev,
-                                        m_options.adjusted_time_callback())) {
+        if (!ContextualCheckBlockHeader(
+                block, state, m_blockman, *this, pindexPrev,
+                m_options.adjusted_time_callback(), test_checkpoints)) {
             LogPrint(BCLog::VALIDATION,
                      "%s: Consensus::ContextualCheckBlockHeader: %s, %s\n",
                      __func__, hash.ToString(), state.ToString());
             return false;
         }
 
         /* Determine if this block descends from any block which has been found
          * invalid (m_failed_blocks), then mark pindexPrev and any blocks
          * between them as failed. For example:
          *
          *                D3
          *              /
          *      B2 - C2
          *    /         \
          *  A             D2 - E2 - F2
          *    \
          *      B1 - C1 - D1 - E1
          *
          * In the case that we attempted to reorg from E1 to F2, only to find
          * C2 to be invalid, we would mark D2, E2, and F2 as BLOCK_FAILED_CHILD
          * but NOT D3 (it was not in any of our candidate sets at the time).
          *
          * In any case D3 will also be marked as BLOCK_FAILED_CHILD at restart
          * in LoadBlockIndex.
          */
         if (!pindexPrev->IsValid(BlockValidity::SCRIPTS)) {
             // The above does not mean "invalid": it checks if the previous
             // block hasn't been validated up to BlockValidity::SCRIPTS. This is
             // a performance optimization, in the common case of adding a new
             // block to the tip, we don't need to iterate over the failed blocks
             // list.
             for (const CBlockIndex *failedit : m_failed_blocks) {
                 if (pindexPrev->GetAncestor(failedit->nHeight) == failedit) {
                     assert(failedit->nStatus.hasFailed());
                     CBlockIndex *invalid_walk = pindexPrev;
                     while (invalid_walk != failedit) {
                         invalid_walk->nStatus =
                             invalid_walk->nStatus.withFailedParent();
                         m_blockman.m_dirty_blockindex.insert(invalid_walk);
                         invalid_walk = invalid_walk->pprev;
                     }
                     LogPrint(BCLog::VALIDATION,
                              "header %s has prev block invalid: %s\n",
                              hash.ToString(), block.hashPrevBlock.ToString());
                     return state.Invalid(
                         BlockValidationResult::BLOCK_INVALID_PREV,
                         "bad-prevblk");
                 }
             }
         }
     }
     if (!min_pow_checked) {
         LogPrint(BCLog::VALIDATION,
                  "%s: not adding new block header %s, missing anti-dos "
                  "proof-of-work validation\n",
                  __func__, hash.ToString());
         return state.Invalid(BlockValidationResult::BLOCK_HEADER_LOW_WORK,
                              "too-little-chainwork");
     }
     CBlockIndex *pindex{m_blockman.AddToBlockIndex(block, m_best_header)};
 
     if (ppindex) {
         *ppindex = pindex;
     }
 
     return true;
 }
 
 // Exposed wrapper for AcceptBlockHeader
 bool ChainstateManager::ProcessNewBlockHeaders(
     const std::vector<CBlockHeader> &headers, bool min_pow_checked,
-    BlockValidationState &state, const CBlockIndex **ppindex) {
+    BlockValidationState &state, const CBlockIndex **ppindex,
+    const std::optional<CCheckpointData> &test_checkpoints) {
     AssertLockNotHeld(cs_main);
     {
         LOCK(cs_main);
         for (const CBlockHeader &header : headers) {
             // Use a temp pindex instead of ppindex to avoid a const_cast
             CBlockIndex *pindex = nullptr;
-            bool accepted =
-                AcceptBlockHeader(header, state, &pindex, min_pow_checked);
+            bool accepted = AcceptBlockHeader(
+                header, state, &pindex, min_pow_checked, test_checkpoints);
             ActiveChainstate().CheckBlockIndex();
 
             if (!accepted) {
                 return false;
             }
 
             if (ppindex) {
                 *ppindex = pindex;
             }
         }
     }
 
     if (NotifyHeaderTip(ActiveChainstate())) {
         if (ActiveChainstate().IsInitialBlockDownload() && ppindex &&
             *ppindex) {
             const CBlockIndex &last_accepted{**ppindex};
             const int64_t blocks_left{
                 (GetTime() - last_accepted.GetBlockTime()) /
                 this->GetConsensus().nPowTargetSpacing};
             const double progress{100.0 * last_accepted.nHeight /
                                   (last_accepted.nHeight + blocks_left)};
             LogPrintf("Synchronizing blockheaders, height: %d (~%.2f%%)\n",
                       last_accepted.nHeight, progress);
         }
     }
     return true;
 }
 
 void ChainstateManager::ReportHeadersPresync(const arith_uint256 &work,
                                              int64_t height,
                                              int64_t timestamp) {
     AssertLockNotHeld(cs_main);
     const auto &chainstate = ActiveChainstate();
     {
         LOCK(cs_main);
         // Don't report headers presync progress if we already have a
         // post-minchainwork header chain.
         // This means we lose reporting for potentially legimate, but unlikely,
         // deep reorgs, but prevent attackers that spam low-work headers from
         // filling our logs.
         if (m_best_header->nChainWork >=
             UintToArith256(GetConsensus().nMinimumChainWork)) {
             return;
         }
         // Rate limit headers presync updates to 4 per second, as these are not
         // subject to DoS protection.
         auto now = Now<SteadyMilliseconds>();
         if (now < m_last_presync_update + 250ms) {
             return;
         }
         m_last_presync_update = now;
     }
     bool initial_download = chainstate.IsInitialBlockDownload();
     uiInterface.NotifyHeaderTip(GetSynchronizationState(initial_download),
                                 height, timestamp, /*presync=*/true);
     if (initial_download) {
         const int64_t blocks_left{(GetTime() - timestamp) /
                                   GetConsensus().nPowTargetSpacing};
         const double progress{100.0 * height / (height + blocks_left)};
         LogPrintf("Pre-synchronizing blockheaders, height: %d (~%.2f%%)\n",
                   height, progress);
     }
 }
 
 /**
  * Store a block on disk.
  *
  * @param[in,out] pblock     The block we want to accept.
  * @param[in]     fRequested A boolean to indicate if this block was requested
  *                           from our peers.
  * @param[in]     dbp        If non-null, the disk position of the block.
  * @param[in,out] fNewBlock  True if block was first received via this call.
  * @param[in]     min_pow_checked  True if proof-of-work anti-DoS checks have
  *                                 been done by caller for headers chain
  * @return True if the block is accepted as a valid block and written to disk.
  */
 bool Chainstate::AcceptBlock(const std::shared_ptr<const CBlock> &pblock,
                              BlockValidationState &state, bool fRequested,
                              const FlatFilePos *dbp, bool *fNewBlock,
                              bool min_pow_checked) {
     AssertLockHeld(cs_main);
 
     const CBlock &block = *pblock;
     if (fNewBlock) {
         *fNewBlock = false;
     }
 
     CBlockIndex *pindex = nullptr;
 
     bool accepted_header{
         m_chainman.AcceptBlockHeader(block, state, &pindex, min_pow_checked)};
     CheckBlockIndex();
 
     if (!accepted_header) {
         return false;
     }
 
     // Try to process all requested blocks that we don't have, but only
     // process an unrequested block if it's new and has enough work to
     // advance our tip, and isn't too many blocks ahead.
     bool fAlreadyHave = pindex->nStatus.hasData();
 
     // TODO: deal better with return value and error conditions for duplicate
     // and unrequested blocks.
     if (fAlreadyHave) {
         return true;
     }
 
     // Compare block header timestamps and received times of the block and the
     // chaintip.  If they have the same chain height, use these diffs as a
     // tie-breaker, attempting to pick the more honestly-mined block.
     int64_t newBlockTimeDiff = std::llabs(pindex->GetReceivedTimeDiff());
     int64_t chainTipTimeDiff =
         m_chain.Tip() ? std::llabs(m_chain.Tip()->GetReceivedTimeDiff()) : 0;
 
     bool isSameHeight =
         m_chain.Tip() && (pindex->nChainWork == m_chain.Tip()->nChainWork);
     if (isSameHeight) {
         LogPrintf("Chain tip timestamp-to-received-time difference: hash=%s, "
                   "diff=%d\n",
                   m_chain.Tip()->GetBlockHash().ToString(), chainTipTimeDiff);
         LogPrintf("New block timestamp-to-received-time difference: hash=%s, "
                   "diff=%d\n",
                   pindex->GetBlockHash().ToString(), newBlockTimeDiff);
     }
 
     bool fHasMoreOrSameWork =
         (m_chain.Tip() ? pindex->nChainWork >= m_chain.Tip()->nChainWork
                        : true);
 
     // Blocks that are too out-of-order needlessly limit the effectiveness of
     // pruning, because pruning will not delete block files that contain any
     // blocks which are too close in height to the tip.  Apply this test
     // regardless of whether pruning is enabled; it should generally be safe to
     // not process unrequested blocks.
     bool fTooFarAhead{pindex->nHeight >
                       m_chain.Height() + int(MIN_BLOCKS_TO_KEEP)};
 
     // TODO: Decouple this function from the block download logic by removing
     // fRequested
     // This requires some new chain data structure to efficiently look up if a
     // block is in a chain leading to a candidate for best tip, despite not
     // being such a candidate itself.
     // Note that this would break the getblockfrompeer RPC
 
     // If we didn't ask for it:
     if (!fRequested) {
         // This is a previously-processed block that was pruned.
         if (pindex->nTx != 0) {
             return true;
         }
 
         // Don't process less-work chains.
         if (!fHasMoreOrSameWork) {
             return true;
         }
 
         // Block height is too high.
         if (fTooFarAhead) {
             return true;
         }
 
         // Protect against DoS attacks from low-work chains.
         // If our tip is behind, a peer could try to send us
         // low-work blocks on a fake chain that we would never
         // request; don't process these.
         if (pindex->nChainWork < m_chainman.MinimumChainWork()) {
             return true;
         }
     }
 
     const CChainParams &params{m_chainman.GetParams()};
     const Consensus::Params &consensusParams = params.GetConsensus();
 
     if (!CheckBlock(block, state, consensusParams,
                     BlockValidationOptions(m_chainman.GetConfig())) ||
         !ContextualCheckBlock(block, state, m_chainman, pindex->pprev)) {
         if (state.IsInvalid() &&
             state.GetResult() != BlockValidationResult::BLOCK_MUTATED) {
             pindex->nStatus = pindex->nStatus.withFailed();
             m_blockman.m_dirty_blockindex.insert(pindex);
         }
 
         return error("%s: %s (block %s)", __func__, state.ToString(),
                      block.GetHash().ToString());
     }
 
     // If connecting the new block would require rewinding more than one block
     // from the active chain (i.e., a "deep reorg"), then mark the new block as
     // parked. If it has enough work then it will be automatically unparked
     // later, during FindMostWorkChain. We mark the block as parked at the very
     // last minute so we can make sure everything is ready to be reorged if
     // needed.
     if (gArgs.GetBoolArg("-parkdeepreorg", true)) {
         const CBlockIndex *pindexFork = m_chain.FindFork(pindex);
         if (pindexFork && pindexFork->nHeight + 1 < m_chain.Height()) {
             LogPrintf("Park block %s as it would cause a deep reorg.\n",
                       pindex->GetBlockHash().ToString());
             pindex->nStatus = pindex->nStatus.withParked();
             m_blockman.m_dirty_blockindex.insert(pindex);
         }
     }
 
     // Header is valid/has work and the merkle tree is good.
     // Relay now, but if it does not build on our best tip, let the
     // SendMessages loop relay it.
     if (!IsInitialBlockDownload() && m_chain.Tip() == pindex->pprev) {
         GetMainSignals().NewPoWValidBlock(pindex, pblock);
     }
 
     // Write block to history file
     if (fNewBlock) {
         *fNewBlock = true;
     }
     try {
         FlatFilePos blockPos{m_blockman.SaveBlockToDisk(block, pindex->nHeight,
                                                         m_chain, params, dbp)};
         if (blockPos.IsNull()) {
             state.Error(strprintf(
                 "%s: Failed to find position to write new block to disk",
                 __func__));
             return false;
         }
         ReceivedBlockTransactions(block, pindex, blockPos);
     } catch (const std::runtime_error &e) {
         return AbortNode(state, std::string("System error: ") + e.what());
     }
 
     FlushStateToDisk(state, FlushStateMode::NONE);
 
     CheckBlockIndex();
 
     return true;
 }
 
 bool ChainstateManager::ProcessNewBlock(
     const std::shared_ptr<const CBlock> &block, bool force_processing,
     bool min_pow_checked, bool *new_block) {
     AssertLockNotHeld(cs_main);
 
     {
         if (new_block) {
             *new_block = false;
         }
 
         BlockValidationState state;
 
         // CheckBlock() does not support multi-threaded block validation
         // because CBlock::fChecked can cause data race.
         // Therefore, the following critical section must include the
         // CheckBlock() call as well.
         LOCK(cs_main);
 
         // Skipping AcceptBlock() for CheckBlock() failures means that we will
         // never mark a block as invalid if CheckBlock() fails.  This is
         // protective against consensus failure if there are any unknown form
         // s of block malleability that cause CheckBlock() to fail; see e.g.
         // CVE-2012-2459 and
         // https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2019-February/016697.html.
         // Because CheckBlock() is not very expensive, the anti-DoS benefits of
         // caching failure (of a definitely-invalid block) are not substantial.
         bool ret = CheckBlock(*block, state, this->GetConsensus(),
                               BlockValidationOptions(this->GetConfig()));
         if (ret) {
             // Store to disk
             ret = ActiveChainstate().AcceptBlock(block, state, force_processing,
                                                  nullptr, new_block,
                                                  min_pow_checked);
         }
 
         if (!ret) {
             GetMainSignals().BlockChecked(*block, state);
             return error("%s: AcceptBlock FAILED (%s)", __func__,
                          state.ToString());
         }
     }
 
     NotifyHeaderTip(ActiveChainstate());
 
     // Only used to report errors, not invalidity - ignore it
     BlockValidationState state;
     if (!ActiveChainstate().ActivateBestChain(state, block)) {
         return error("%s: ActivateBestChain failed (%s)", __func__,
                      state.ToString());
     }
 
     return true;
 }
 
 MempoolAcceptResult
 ChainstateManager::ProcessTransaction(const CTransactionRef &tx,
                                       bool test_accept) {
     AssertLockHeld(cs_main);
     Chainstate &active_chainstate = ActiveChainstate();
     if (!active_chainstate.GetMempool()) {
         TxValidationState state;
         state.Invalid(TxValidationResult::TX_NO_MEMPOOL, "no-mempool");
         return MempoolAcceptResult::Failure(state);
     }
     auto result = AcceptToMemoryPool(active_chainstate, tx, GetTime(),
                                      /*bypass_limits=*/false, test_accept);
     active_chainstate.GetMempool()->check(
         active_chainstate.CoinsTip(), active_chainstate.m_chain.Height() + 1);
     return result;
 }
 
 bool TestBlockValidity(
     BlockValidationState &state, const CChainParams &params,
     Chainstate &chainstate, const CBlock &block, CBlockIndex *pindexPrev,
     const std::function<NodeClock::time_point()> &adjusted_time_callback,
     BlockValidationOptions validationOptions) {
     AssertLockHeld(cs_main);
     assert(pindexPrev && pindexPrev == chainstate.m_chain.Tip());
     CCoinsViewCache viewNew(&chainstate.CoinsTip());
     BlockHash block_hash(block.GetHash());
     CBlockIndex indexDummy(block);
     indexDummy.pprev = pindexPrev;
     indexDummy.nHeight = pindexPrev->nHeight + 1;
     indexDummy.phashBlock = &block_hash;
 
     // NOTE: CheckBlockHeader is called by CheckBlock
     if (!ContextualCheckBlockHeader(block, state, chainstate.m_blockman,
                                     chainstate.m_chainman, pindexPrev,
                                     adjusted_time_callback())) {
         return error("%s: Consensus::ContextualCheckBlockHeader: %s", __func__,
                      state.ToString());
     }
 
     if (!CheckBlock(block, state, params.GetConsensus(), validationOptions)) {
         return error("%s: Consensus::CheckBlock: %s", __func__,
                      state.ToString());
     }
 
     if (!ContextualCheckBlock(block, state, chainstate.m_chainman,
                               pindexPrev)) {
         return error("%s: Consensus::ContextualCheckBlock: %s", __func__,
                      state.ToString());
     }
 
     if (!chainstate.ConnectBlock(block, state, &indexDummy, viewNew,
                                  validationOptions, nullptr, true)) {
         return false;
     }
 
     assert(state.IsValid());
     return true;
 }
 
 /* This function is called from the RPC code for pruneblockchain */
 void PruneBlockFilesManual(Chainstate &active_chainstate,
                            int nManualPruneHeight) {
     BlockValidationState state;
     if (active_chainstate.FlushStateToDisk(state, FlushStateMode::NONE,
                                            nManualPruneHeight)) {
         LogPrintf("%s: failed to flush state (%s)\n", __func__,
                   state.ToString());
     }
 }
 
 void Chainstate::LoadMempool(const fs::path &load_path,
                              FopenFn mockable_fopen_function) {
     if (!m_mempool) {
         return;
     }
     ::LoadMempool(*m_mempool, load_path, *this, mockable_fopen_function);
     m_mempool->SetLoadTried(!ShutdownRequested());
 }
 
 bool Chainstate::LoadChainTip() {
     AssertLockHeld(cs_main);
     const CCoinsViewCache &coins_cache = CoinsTip();
     // Never called when the coins view is empty
     assert(!coins_cache.GetBestBlock().IsNull());
     const CBlockIndex *tip = m_chain.Tip();
 
     if (tip && tip->GetBlockHash() == coins_cache.GetBestBlock()) {
         return true;
     }
 
     // Load pointer to end of best chain
     CBlockIndex *pindex =
         m_blockman.LookupBlockIndex(coins_cache.GetBestBlock());
     if (!pindex) {
         return false;
     }
     m_chain.SetTip(pindex);
     PruneBlockIndexCandidates();
 
     tip = m_chain.Tip();
     LogPrintf(
         "Loaded best chain: hashBestChain=%s height=%d date=%s progress=%f\n",
         tip->GetBlockHash().ToString(), m_chain.Height(),
         FormatISO8601DateTime(tip->GetBlockTime()),
         GuessVerificationProgress(m_chainman.GetParams().TxData(), tip));
     return true;
 }
 
 CVerifyDB::CVerifyDB() {
     uiInterface.ShowProgress(_("Verifying blocks...").translated, 0, false);
 }
 
 CVerifyDB::~CVerifyDB() {
     uiInterface.ShowProgress("", 100, false);
 }
 
 VerifyDBResult CVerifyDB::VerifyDB(Chainstate &chainstate,
                                    CCoinsView &coinsview, int nCheckLevel,
                                    int nCheckDepth) {
     AssertLockHeld(cs_main);
 
     const Config &config = chainstate.m_chainman.GetConfig();
     const CChainParams &params = config.GetChainParams();
     const Consensus::Params &consensusParams = params.GetConsensus();
 
     if (chainstate.m_chain.Tip() == nullptr ||
         chainstate.m_chain.Tip()->pprev == nullptr) {
         return VerifyDBResult::SUCCESS;
     }
 
     // Verify blocks in the best chain
     if (nCheckDepth <= 0 || nCheckDepth > chainstate.m_chain.Height()) {
         nCheckDepth = chainstate.m_chain.Height();
     }
 
     nCheckLevel = std::max(0, std::min(4, nCheckLevel));
     LogPrintf("Verifying last %i blocks at level %i\n", nCheckDepth,
               nCheckLevel);
 
     CCoinsViewCache coins(&coinsview);
     CBlockIndex *pindex;
     CBlockIndex *pindexFailure = nullptr;
     int nGoodTransactions = 0;
     BlockValidationState state;
     int reportDone = 0;
     bool skipped_no_block_data{false};
     bool skipped_l3_checks{false};
     LogPrintf("Verification progress: 0%%\n");
 
     const bool is_snapshot_cs{!chainstate.m_from_snapshot_blockhash};
 
     for (pindex = chainstate.m_chain.Tip(); pindex && pindex->pprev;
          pindex = pindex->pprev) {
         const int percentageDone = std::max(
             1, std::min(99, (int)(((double)(chainstate.m_chain.Height() -
                                             pindex->nHeight)) /
                                   (double)nCheckDepth *
                                   (nCheckLevel >= 4 ? 50 : 100))));
         if (reportDone < percentageDone / 10) {
             // report every 10% step
             LogPrintf("Verification progress: %d%%\n", percentageDone);
             reportDone = percentageDone / 10;
         }
 
         uiInterface.ShowProgress(_("Verifying blocks...").translated,
                                  percentageDone, false);
         if (pindex->nHeight <= chainstate.m_chain.Height() - nCheckDepth) {
             break;
         }
 
         if ((chainstate.m_blockman.IsPruneMode() || is_snapshot_cs) &&
             !pindex->nStatus.hasData()) {
             // If pruning or running under an assumeutxo snapshot, only go
             // back as far as we have data.
             LogPrintf("VerifyDB(): block verification stopping at height %d "
                       "(no data). This could be due to pruning or use of an "
                       "assumeutxo snapshot.\n",
                       pindex->nHeight);
             skipped_no_block_data = true;
             break;
         }
 
         CBlock block;
 
         // check level 0: read from disk
         if (!ReadBlockFromDisk(block, pindex, consensusParams)) {
             LogPrintf(
                 "Verification error: ReadBlockFromDisk failed at %d, hash=%s\n",
                 pindex->nHeight, pindex->GetBlockHash().ToString());
             return VerifyDBResult::CORRUPTED_BLOCK_DB;
         }
 
         // check level 1: verify block validity
         if (nCheckLevel >= 1 && !CheckBlock(block, state, consensusParams,
                                             BlockValidationOptions(config))) {
             LogPrintf(
                 "Verification error: found bad block at %d, hash=%s (%s)\n",
                 pindex->nHeight, pindex->GetBlockHash().ToString(),
                 state.ToString());
             return VerifyDBResult::CORRUPTED_BLOCK_DB;
         }
 
         // check level 2: verify undo validity
         if (nCheckLevel >= 2 && pindex) {
             CBlockUndo undo;
             if (!pindex->GetUndoPos().IsNull()) {
                 if (!UndoReadFromDisk(undo, pindex)) {
                     LogPrintf("Verification error: found bad undo data at %d, "
                               "hash=%s\n",
                               pindex->nHeight,
                               pindex->GetBlockHash().ToString());
                     return VerifyDBResult::CORRUPTED_BLOCK_DB;
                 }
             }
         }
         // check level 3: check for inconsistencies during memory-only
         // disconnect of tip blocks
         size_t curr_coins_usage = coins.DynamicMemoryUsage() +
                                   chainstate.CoinsTip().DynamicMemoryUsage();
 
         if (nCheckLevel >= 3) {
             if (curr_coins_usage <= chainstate.m_coinstip_cache_size_bytes) {
                 assert(coins.GetBestBlock() == pindex->GetBlockHash());
                 DisconnectResult res =
                     chainstate.DisconnectBlock(block, pindex, coins);
                 if (res == DisconnectResult::FAILED) {
                     LogPrintf("Verification error: irrecoverable inconsistency "
                               "in block data at %d, hash=%s\n",
                               pindex->nHeight,
                               pindex->GetBlockHash().ToString());
                     return VerifyDBResult::CORRUPTED_BLOCK_DB;
                 }
                 if (res == DisconnectResult::UNCLEAN) {
                     nGoodTransactions = 0;
                     pindexFailure = pindex;
                 } else {
                     nGoodTransactions += block.vtx.size();
                 }
             } else {
                 skipped_l3_checks = true;
             }
         }
 
         if (ShutdownRequested()) {
             return VerifyDBResult::INTERRUPTED;
         }
     }
 
     if (pindexFailure) {
         LogPrintf("Verification error: coin database inconsistencies found "
                   "(last %i blocks, %i good transactions before that)\n",
                   chainstate.m_chain.Height() - pindexFailure->nHeight + 1,
                   nGoodTransactions);
         return VerifyDBResult::CORRUPTED_BLOCK_DB;
     }
     if (skipped_l3_checks) {
         LogPrintf("Skipped verification of level >=3 (insufficient database "
                   "cache size). Consider increasing -dbcache.\n");
     }
 
     // store block count as we move pindex at check level >= 4
     int block_count = chainstate.m_chain.Height() - pindex->nHeight;
 
     // check level 4: try reconnecting blocks
     if (nCheckLevel >= 4 && !skipped_l3_checks) {
         while (pindex != chainstate.m_chain.Tip()) {
             const int percentageDone = std::max(
                 1, std::min(99, 100 - int(double(chainstate.m_chain.Height() -
                                                  pindex->nHeight) /
                                           double(nCheckDepth) * 50)));
             if (reportDone < percentageDone / 10) {
                 // report every 10% step
                 LogPrintf("Verification progress: %d%%\n", percentageDone);
                 reportDone = percentageDone / 10;
             }
             uiInterface.ShowProgress(_("Verifying blocks...").translated,
                                      percentageDone, false);
             pindex = chainstate.m_chain.Next(pindex);
             CBlock block;
             if (!ReadBlockFromDisk(block, pindex, consensusParams)) {
                 LogPrintf("Verification error: ReadBlockFromDisk failed at %d, "
                           "hash=%s\n",
                           pindex->nHeight, pindex->GetBlockHash().ToString());
                 return VerifyDBResult::CORRUPTED_BLOCK_DB;
             }
             if (!chainstate.ConnectBlock(block, state, pindex, coins,
                                          BlockValidationOptions(config))) {
                 LogPrintf("Verification error: found unconnectable block at "
                           "%d, hash=%s (%s)\n",
                           pindex->nHeight, pindex->GetBlockHash().ToString(),
                           state.ToString());
                 return VerifyDBResult::CORRUPTED_BLOCK_DB;
             }
             if (ShutdownRequested()) {
                 return VerifyDBResult::INTERRUPTED;
             }
         }
     }
 
     LogPrintf("Verification: No coin database inconsistencies in last %i "
               "blocks (%i transactions)\n",
               block_count, nGoodTransactions);
 
     if (skipped_l3_checks) {
         return VerifyDBResult::SKIPPED_L3_CHECKS;
     }
     if (skipped_no_block_data) {
         return VerifyDBResult::SKIPPED_MISSING_BLOCKS;
     }
     return VerifyDBResult::SUCCESS;
 }
 
 /**
  * Apply the effects of a block on the utxo cache, ignoring that it may already
  * have been applied.
  */
 bool Chainstate::RollforwardBlock(const CBlockIndex *pindex,
                                   CCoinsViewCache &view) {
     AssertLockHeld(cs_main);
     // TODO: merge with ConnectBlock
     CBlock block;
     if (!ReadBlockFromDisk(block, pindex, m_chainman.GetConsensus())) {
         return error("ReplayBlock(): ReadBlockFromDisk failed at %d, hash=%s",
                      pindex->nHeight, pindex->GetBlockHash().ToString());
     }
 
     for (const CTransactionRef &tx : block.vtx) {
         // Pass check = true as every addition may be an overwrite.
         AddCoins(view, *tx, pindex->nHeight, true);
     }
 
     for (const CTransactionRef &tx : block.vtx) {
         if (tx->IsCoinBase()) {
             continue;
         }
 
         for (const CTxIn &txin : tx->vin) {
             view.SpendCoin(txin.prevout);
         }
     }
 
     return true;
 }
 
 bool Chainstate::ReplayBlocks() {
     LOCK(cs_main);
 
     CCoinsView &db = this->CoinsDB();
     CCoinsViewCache cache(&db);
 
     std::vector<BlockHash> hashHeads = db.GetHeadBlocks();
     if (hashHeads.empty()) {
         // We're already in a consistent state.
         return true;
     }
     if (hashHeads.size() != 2) {
         return error("ReplayBlocks(): unknown inconsistent state");
     }
 
     uiInterface.ShowProgress(_("Replaying blocks...").translated, 0, false);
     LogPrintf("Replaying blocks\n");
 
     // Old tip during the interrupted flush.
     const CBlockIndex *pindexOld = nullptr;
     // New tip during the interrupted flush.
     const CBlockIndex *pindexNew;
     // Latest block common to both the old and the new tip.
     const CBlockIndex *pindexFork = nullptr;
 
     if (m_blockman.m_block_index.count(hashHeads[0]) == 0) {
         return error(
             "ReplayBlocks(): reorganization to unknown block requested");
     }
 
     pindexNew = &(m_blockman.m_block_index[hashHeads[0]]);
 
     if (!hashHeads[1].IsNull()) {
         // The old tip is allowed to be 0, indicating it's the first flush.
         if (m_blockman.m_block_index.count(hashHeads[1]) == 0) {
             return error(
                 "ReplayBlocks(): reorganization from unknown block requested");
         }
 
         pindexOld = &(m_blockman.m_block_index[hashHeads[1]]);
         pindexFork = LastCommonAncestor(pindexOld, pindexNew);
         assert(pindexFork != nullptr);
     }
 
     // Rollback along the old branch.
     while (pindexOld != pindexFork) {
         if (pindexOld->nHeight > 0) {
             // Never disconnect the genesis block.
             CBlock block;
             if (!ReadBlockFromDisk(block, pindexOld,
                                    m_chainman.GetConsensus())) {
                 return error("RollbackBlock(): ReadBlockFromDisk() failed at "
                              "%d, hash=%s",
                              pindexOld->nHeight,
                              pindexOld->GetBlockHash().ToString());
             }
 
             LogPrintf("Rolling back %s (%i)\n",
                       pindexOld->GetBlockHash().ToString(), pindexOld->nHeight);
             DisconnectResult res = DisconnectBlock(block, pindexOld, cache);
             if (res == DisconnectResult::FAILED) {
                 return error(
                     "RollbackBlock(): DisconnectBlock failed at %d, hash=%s",
                     pindexOld->nHeight, pindexOld->GetBlockHash().ToString());
             }
 
             // If DisconnectResult::UNCLEAN is returned, it means a non-existing
             // UTXO was deleted, or an existing UTXO was overwritten. It
             // corresponds to cases where the block-to-be-disconnect never had
             // all its operations applied to the UTXO set. However, as both
             // writing a UTXO and deleting a UTXO are idempotent operations, the
             // result is still a version of the UTXO set with the effects of
             // that block undone.
         }
         pindexOld = pindexOld->pprev;
     }
 
     // Roll forward from the forking point to the new tip.
     int nForkHeight = pindexFork ? pindexFork->nHeight : 0;
     for (int nHeight = nForkHeight + 1; nHeight <= pindexNew->nHeight;
          ++nHeight) {
         const CBlockIndex &pindex{*Assert(pindexNew->GetAncestor(nHeight))};
         LogPrintf("Rolling forward %s (%i)\n", pindex.GetBlockHash().ToString(),
                   nHeight);
         uiInterface.ShowProgress(_("Replaying blocks...").translated,
                                  (int)((nHeight - nForkHeight) * 100.0 /
                                        (pindexNew->nHeight - nForkHeight)),
                                  false);
         if (!RollforwardBlock(&pindex, cache)) {
             return false;
         }
     }
 
     cache.SetBestBlock(pindexNew->GetBlockHash());
     cache.Flush();
     uiInterface.ShowProgress("", 100, false);
     return true;
 }
 
 // May NOT be used after any connections are up as much of the peer-processing
 // logic assumes a consistent block index state
 void Chainstate::UnloadBlockIndex() {
     AssertLockHeld(::cs_main);
     nBlockSequenceId = 1;
     m_best_fork_tip = nullptr;
     m_best_fork_base = nullptr;
     setBlockIndexCandidates.clear();
 }
 
 bool ChainstateManager::LoadBlockIndex() {
     AssertLockHeld(cs_main);
     // Load block index from databases
     bool needs_init = fReindex;
     if (!fReindex) {
         bool ret = m_blockman.LoadBlockIndexDB(GetConsensus());
         if (!ret) {
             return false;
         }
 
         std::vector<CBlockIndex *> vSortedByHeight{
             m_blockman.GetAllBlockIndices()};
         std::sort(vSortedByHeight.begin(), vSortedByHeight.end(),
                   CBlockIndexHeightOnlyComparator());
 
         // Find start of assumed-valid region.
         int first_assumed_valid_height = std::numeric_limits<int>::max();
 
         for (const CBlockIndex *block : vSortedByHeight) {
             if (block->IsAssumedValid()) {
                 auto chainstates = GetAll();
 
                 // If we encounter an assumed-valid block index entry, ensure
                 // that we have one chainstate that tolerates assumed-valid
                 // entries and another that does not (i.e. the background
                 // validation chainstate), since assumed-valid entries should
                 // always be pending validation by a fully-validated chainstate.
                 auto any_chain = [&](auto fnc) {
                     return std::any_of(chainstates.cbegin(), chainstates.cend(),
                                        fnc);
                 };
                 assert(any_chain([](auto chainstate) {
                     return chainstate->reliesOnAssumedValid();
                 }));
                 assert(any_chain([](auto chainstate) {
                     return !chainstate->reliesOnAssumedValid();
                 }));
 
                 first_assumed_valid_height = block->nHeight;
                 LogPrintf("Saw first assumedvalid block at height %d (%s)\n",
                           first_assumed_valid_height, block->ToString());
                 break;
             }
         }
 
         for (CBlockIndex *pindex : vSortedByHeight) {
             if (ShutdownRequested()) {
                 return false;
             }
             if (pindex->IsAssumedValid() ||
                 (pindex->IsValid(BlockValidity::TRANSACTIONS) &&
                  (pindex->HaveTxsDownloaded() || pindex->pprev == nullptr))) {
                 // Fill each chainstate's block candidate set. Only add
                 // assumed-valid blocks to the tip candidate set if the
                 // chainstate is allowed to rely on assumed-valid blocks.
                 //
                 // If all setBlockIndexCandidates contained the assumed-valid
                 // blocks, the background chainstate's ActivateBestChain() call
                 // would add assumed-valid blocks to the chain (based on how
                 // FindMostWorkChain() works). Obviously we don't want this
                 // since the purpose of the background validation chain is to
                 // validate assumed-valid blocks.
                 //
                 // Note: This is considering all blocks whose height is greater
                 // or equal to the first assumed-valid block to be assumed-valid
                 // blocks, and excluding them from the background chainstate's
                 // setBlockIndexCandidates set. This does mean that some blocks
                 // which are not technically assumed-valid (later blocks on a
                 // fork beginning before the first assumed-valid block) might
                 // not get added to the background chainstate, but this is ok,
                 // because they will still be attached to the active chainstate
                 // if they actually contain more work.
                 //
                 // Instead of this height-based approach, an earlier attempt was
                 // made at detecting "holistically" whether the block index
                 // under consideration relied on an assumed-valid ancestor, but
                 // this proved to be too slow to be practical.
                 for (Chainstate *chainstate : GetAll()) {
                     if (chainstate->reliesOnAssumedValid() ||
                         pindex->nHeight < first_assumed_valid_height) {
                         chainstate->setBlockIndexCandidates.insert(pindex);
                     }
                 }
             }
 
             if (pindex->nStatus.isInvalid() &&
                 (!m_best_invalid ||
                  pindex->nChainWork > m_best_invalid->nChainWork)) {
                 m_best_invalid = pindex;
             }
 
             if (pindex->nStatus.isOnParkedChain() &&
                 (!m_best_parked ||
                  pindex->nChainWork > m_best_parked->nChainWork)) {
                 m_best_parked = pindex;
             }
 
             if (pindex->IsValid(BlockValidity::TREE) &&
                 (m_best_header == nullptr ||
                  CBlockIndexWorkComparator()(m_best_header, pindex))) {
                 m_best_header = pindex;
             }
         }
 
         needs_init = m_blockman.m_block_index.empty();
     }
 
     if (needs_init) {
         // Everything here is for *new* reindex/DBs. Thus, though
         // LoadBlockIndexDB may have set fReindex if we shut down
         // mid-reindex previously, we don't check fReindex and
         // instead only check it prior to LoadBlockIndexDB to set
         // needs_init.
 
         LogPrintf("Initializing databases...\n");
     }
     return true;
 }
 
 bool Chainstate::LoadGenesisBlock() {
     LOCK(cs_main);
 
     const CChainParams &params{m_chainman.GetParams()};
 
     // Check whether we're already initialized by checking for genesis in
     // m_blockman.m_block_index. Note that we can't use m_chain here, since it
     // is set based on the coins db, not the block index db, which is the only
     // thing loaded at this point.
     if (m_blockman.m_block_index.count(params.GenesisBlock().GetHash())) {
         return true;
     }
 
     try {
         const CBlock &block = params.GenesisBlock();
         FlatFilePos blockPos{
             m_blockman.SaveBlockToDisk(block, 0, m_chain, params, nullptr)};
         if (blockPos.IsNull()) {
             return error("%s: writing genesis block to disk failed", __func__);
         }
         CBlockIndex *pindex =
             m_blockman.AddToBlockIndex(block, m_chainman.m_best_header);
         ReceivedBlockTransactions(block, pindex, blockPos);
     } catch (const std::runtime_error &e) {
         return error("%s: failed to write genesis block: %s", __func__,
                      e.what());
     }
 
     return true;
 }
 
 void Chainstate::LoadExternalBlockFile(
     FILE *fileIn, FlatFilePos *dbp,
     std::multimap<BlockHash, FlatFilePos> *blocks_with_unknown_parent) {
     AssertLockNotHeld(m_chainstate_mutex);
 
     // Either both should be specified (-reindex), or neither (-loadblock).
     assert(!dbp == !blocks_with_unknown_parent);
 
     int64_t nStart = GetTimeMillis();
     const CChainParams &params{m_chainman.GetParams()};
 
     int nLoaded = 0;
     try {
         // This takes over fileIn and calls fclose() on it in the CBufferedFile
         // destructor. Make sure we have at least 2*MAX_TX_SIZE space in there
         // so any transaction can fit in the buffer.
         CBufferedFile blkdat(fileIn, 2 * MAX_TX_SIZE, MAX_TX_SIZE + 8, SER_DISK,
                              CLIENT_VERSION);
         uint64_t nRewind = blkdat.GetPos();
         while (!blkdat.eof()) {
             if (ShutdownRequested()) {
                 return;
             }
 
             blkdat.SetPos(nRewind);
             // Start one byte further next time, in case of failure.
             nRewind++;
             // Remove former limit.
             blkdat.SetLimit();
             unsigned int nSize = 0;
             try {
                 // Locate a header.
                 uint8_t buf[CMessageHeader::MESSAGE_START_SIZE];
                 blkdat.FindByte(char(params.DiskMagic()[0]));
                 nRewind = blkdat.GetPos() + 1;
                 blkdat >> buf;
                 if (memcmp(buf, params.DiskMagic().data(),
                            CMessageHeader::MESSAGE_START_SIZE)) {
                     continue;
                 }
 
                 // Read size.
                 blkdat >> nSize;
                 if (nSize < 80) {
                     continue;
                 }
             } catch (const std::exception &) {
                 // No valid block header found; don't complain.
                 break;
             }
 
             try {
                 // read block
                 uint64_t nBlockPos = blkdat.GetPos();
                 if (dbp) {
                     dbp->nPos = nBlockPos;
                 }
                 blkdat.SetLimit(nBlockPos + nSize);
                 std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>();
                 CBlock &block = *pblock;
                 blkdat >> block;
                 nRewind = blkdat.GetPos();
 
                 const BlockHash hash = block.GetHash();
                 {
                     LOCK(cs_main);
                     // detect out of order blocks, and store them for later
                     if (hash != params.GetConsensus().hashGenesisBlock &&
                         !m_blockman.LookupBlockIndex(block.hashPrevBlock)) {
                         LogPrint(
                             BCLog::REINDEX,
                             "%s: Out of order block %s, parent %s not known\n",
                             __func__, hash.ToString(),
                             block.hashPrevBlock.ToString());
                         if (dbp && blocks_with_unknown_parent) {
                             blocks_with_unknown_parent->emplace(
                                 block.hashPrevBlock, *dbp);
                         }
                         continue;
                     }
 
                     // process in case the block isn't known yet
                     const CBlockIndex *pindex =
                         m_blockman.LookupBlockIndex(hash);
                     if (!pindex || !pindex->nStatus.hasData()) {
                         BlockValidationState state;
                         if (AcceptBlock(pblock, state, true, dbp, nullptr,
                                         true)) {
                             nLoaded++;
                         }
                         if (state.IsError()) {
                             break;
                         }
                     } else if (hash != params.GetConsensus().hashGenesisBlock &&
                                pindex->nHeight % 1000 == 0) {
                         LogPrint(
                             BCLog::REINDEX,
                             "Block Import: already had block %s at height %d\n",
                             hash.ToString(), pindex->nHeight);
                     }
                 }
 
                 // Activate the genesis block so normal node progress can
                 // continue
                 if (hash == params.GetConsensus().hashGenesisBlock) {
                     BlockValidationState state;
                     if (!ActivateBestChain(state, nullptr)) {
                         break;
                     }
                 }
 
                 if (m_blockman.IsPruneMode() && !fReindex && pblock) {
                     // Must update the tip for pruning to work while importing
                     // with -loadblock. This is a tradeoff to conserve disk
                     // space at the expense of time spent updating the tip to be
                     // able to prune. Otherwise, ActivateBestChain won't be
                     // called by the import process until after all of the block
                     // files are loaded. ActivateBestChain can be called by
                     // concurrent network message processing, but that is not
                     // reliable for the purpose of pruning while importing.
                     BlockValidationState state;
                     if (!ActivateBestChain(state, pblock)) {
                         LogPrint(BCLog::REINDEX,
                                  "failed to activate chain (%s)\n",
                                  state.ToString());
                         break;
                     }
                 }
 
                 NotifyHeaderTip(*this);
 
                 if (!blocks_with_unknown_parent) {
                     continue;
                 }
 
                 // Recursively process earlier encountered successors of this
                 // block
                 std::deque<BlockHash> queue;
                 queue.push_back(hash);
                 while (!queue.empty()) {
                     BlockHash head = queue.front();
                     queue.pop_front();
                     auto range = blocks_with_unknown_parent->equal_range(head);
                     while (range.first != range.second) {
                         std::multimap<BlockHash, FlatFilePos>::iterator it =
                             range.first;
                         std::shared_ptr<CBlock> pblockrecursive =
                             std::make_shared<CBlock>();
                         if (ReadBlockFromDisk(*pblockrecursive, it->second,
                                               params.GetConsensus())) {
                             LogPrint(
                                 BCLog::REINDEX,
                                 "%s: Processing out of order child %s of %s\n",
                                 __func__, pblockrecursive->GetHash().ToString(),
                                 head.ToString());
                             LOCK(cs_main);
                             BlockValidationState dummy;
                             if (AcceptBlock(pblockrecursive, dummy, true,
                                             &it->second, nullptr, true)) {
                                 nLoaded++;
                                 queue.push_back(pblockrecursive->GetHash());
                             }
                         }
                         range.first++;
                         blocks_with_unknown_parent->erase(it);
                         NotifyHeaderTip(*this);
                     }
                 }
             } catch (const std::exception &e) {
                 // Historical bugs added extra data to the block files that does
                 // not deserialize cleanly. Commonly this data is between
                 // readable blocks, but it does not really matter. Such data is
                 // not fatal to the import process. The code that reads the
                 // block files deals with invalid data by simply ignoring it. It
                 // continues to search for the next {4 byte magic message start
                 // bytes + 4 byte length + block} that does deserialize cleanly
                 // and passes all of the other block validation checks dealing
                 // with POW and the merkle root, etc... We merely note with this
                 // informational log message when unexpected data is
                 // encountered. We could also be experiencing a storage system
                 // read error, or a read of a previous bad write. These are
                 // possible, but less likely scenarios. We don't have enough
                 // information to tell a difference here. The reindex process is
                 // not the place to attempt to clean and/or compact the block
                 // files. If so desired, a studious node operator may use
                 // knowledge of the fact that the block files are not entirely
                 // pristine in order to prepare a set of pristine, and perhaps
                 // ordered, block files for later reindexing.
                 LogPrint(BCLog::REINDEX,
                          "%s: unexpected data at file offset 0x%x - %s. "
                          "continuing\n",
                          __func__, (nRewind - 1), e.what());
             }
         }
     } catch (const std::runtime_error &e) {
         AbortNode(std::string("System error: ") + e.what());
     }
 
     LogPrintf("Loaded %i blocks from external file in %dms\n", nLoaded,
               GetTimeMillis() - nStart);
 }
 
 void Chainstate::CheckBlockIndex() {
     if (!m_chainman.ShouldCheckBlockIndex()) {
         return;
     }
 
     LOCK(cs_main);
 
     // During a reindex, we read the genesis block and call CheckBlockIndex
     // before ActivateBestChain, so we have the genesis block in
     // m_blockman.m_block_index but no active chain. (A few of the tests when
     // iterating the block tree require that m_chain has been initialized.)
     if (m_chain.Height() < 0) {
         assert(m_blockman.m_block_index.size() <= 1);
         return;
     }
 
     // Build forward-pointing map of the entire block tree.
     std::multimap<CBlockIndex *, CBlockIndex *> forward;
     for (auto &[_, block_index] : m_blockman.m_block_index) {
         forward.emplace(block_index.pprev, &block_index);
     }
 
     assert(forward.size() == m_blockman.m_block_index.size());
 
     std::pair<std::multimap<CBlockIndex *, CBlockIndex *>::iterator,
               std::multimap<CBlockIndex *, CBlockIndex *>::iterator>
         rangeGenesis = forward.equal_range(nullptr);
     CBlockIndex *pindex = rangeGenesis.first->second;
     rangeGenesis.first++;
     // There is only one index entry with parent nullptr.
     assert(rangeGenesis.first == rangeGenesis.second);
 
     // Iterate over the entire block tree, using depth-first search.
     // Along the way, remember whether there are blocks on the path from genesis
     // block being explored which are the first to have certain properties.
     size_t nNodes = 0;
     int nHeight = 0;
     // Oldest ancestor of pindex which is invalid.
     CBlockIndex *pindexFirstInvalid = nullptr;
     // Oldest ancestor of pindex which is parked.
     CBlockIndex *pindexFirstParked = nullptr;
     // Oldest ancestor of pindex which does not have data available.
     CBlockIndex *pindexFirstMissing = nullptr;
     // Oldest ancestor of pindex for which nTx == 0.
     CBlockIndex *pindexFirstNeverProcessed = nullptr;
     // Oldest ancestor of pindex which does not have BLOCK_VALID_TREE
     // (regardless of being valid or not).
     CBlockIndex *pindexFirstNotTreeValid = nullptr;
     // Oldest ancestor of pindex which does not have BLOCK_VALID_TRANSACTIONS
     // (regardless of being valid or not).
     CBlockIndex *pindexFirstNotTransactionsValid = nullptr;
     // Oldest ancestor of pindex which does not have BLOCK_VALID_CHAIN
     // (regardless of being valid or not).
     CBlockIndex *pindexFirstNotChainValid = nullptr;
     // Oldest ancestor of pindex which does not have BLOCK_VALID_SCRIPTS
     // (regardless of being valid or not).
     CBlockIndex *pindexFirstNotScriptsValid = nullptr;
     while (pindex != nullptr) {
         nNodes++;
         if (pindexFirstInvalid == nullptr && pindex->nStatus.hasFailed()) {
             pindexFirstInvalid = pindex;
         }
         if (pindexFirstParked == nullptr && pindex->nStatus.isParked()) {
             pindexFirstParked = pindex;
         }
         // Assumed-valid index entries will not have data since we haven't
         // downloaded the full block yet.
         if (pindexFirstMissing == nullptr && !pindex->nStatus.hasData() &&
             !pindex->IsAssumedValid()) {
             pindexFirstMissing = pindex;
         }
         if (pindexFirstNeverProcessed == nullptr && pindex->nTx == 0) {
             pindexFirstNeverProcessed = pindex;
         }
         if (pindex->pprev != nullptr && pindexFirstNotTreeValid == nullptr &&
             pindex->nStatus.getValidity() < BlockValidity::TREE) {
             pindexFirstNotTreeValid = pindex;
         }
         if (pindex->pprev != nullptr && !pindex->IsAssumedValid()) {
             if (pindexFirstNotTransactionsValid == nullptr &&
                 pindex->nStatus.getValidity() < BlockValidity::TRANSACTIONS) {
                 pindexFirstNotTransactionsValid = pindex;
             }
             if (pindexFirstNotChainValid == nullptr &&
                 pindex->nStatus.getValidity() < BlockValidity::CHAIN) {
                 pindexFirstNotChainValid = pindex;
             }
             if (pindexFirstNotScriptsValid == nullptr &&
                 pindex->nStatus.getValidity() < BlockValidity::SCRIPTS) {
                 pindexFirstNotScriptsValid = pindex;
             }
         }
 
         // Begin: actual consistency checks.
         if (pindex->pprev == nullptr) {
             // Genesis block checks.
             // Genesis block's hash must match.
             assert(pindex->GetBlockHash() ==
                    m_chainman.GetConsensus().hashGenesisBlock);
             // The current active chain's genesis block must be this block.
             assert(pindex == m_chain.Genesis());
         }
         if (!pindex->HaveTxsDownloaded()) {
             // nSequenceId can't be set positive for blocks that aren't linked
             // (negative is used for preciousblock)
             assert(pindex->nSequenceId <= 0);
         }
         // VALID_TRANSACTIONS is equivalent to nTx > 0 for all nodes (whether or
         // not pruning has occurred). HAVE_DATA is only equivalent to nTx > 0
         // (or VALID_TRANSACTIONS) if no pruning has occurred.
         // Unless these indexes are assumed valid and pending block download on
         // a background chainstate.
         if (!m_blockman.m_have_pruned && !pindex->IsAssumedValid()) {
             // If we've never pruned, then HAVE_DATA should be equivalent to nTx
             // > 0
             assert(pindex->nStatus.hasData() == (pindex->nTx > 0));
             assert(pindexFirstMissing == pindexFirstNeverProcessed);
         } else if (pindex->nStatus.hasData()) {
             // If we have pruned, then we can only say that HAVE_DATA implies
             // nTx > 0
             assert(pindex->nTx > 0);
         }
         if (pindex->nStatus.hasUndo()) {
             assert(pindex->nStatus.hasData());
         }
         if (pindex->IsAssumedValid()) {
             // Assumed-valid blocks should have some nTx value.
             assert(pindex->nTx > 0);
             // Assumed-valid blocks should connect to the main chain.
             assert(pindex->nStatus.getValidity() >= BlockValidity::TREE);
         } else {
             // Otherwise there should only be an nTx value if we have
             // actually seen a block's transactions.
             // This is pruning-independent.
             assert((pindex->nStatus.getValidity() >=
                     BlockValidity::TRANSACTIONS) == (pindex->nTx > 0));
         }
         // All parents having had data (at some point) is equivalent to all
         // parents being VALID_TRANSACTIONS, which is equivalent to
         // HaveTxsDownloaded(). All parents having had data (at some point) is
         // equivalent to all parents being VALID_TRANSACTIONS, which is
         // equivalent to HaveTxsDownloaded().
         assert((pindexFirstNeverProcessed == nullptr) ==
                (pindex->HaveTxsDownloaded()));
         assert((pindexFirstNotTransactionsValid == nullptr) ==
                (pindex->HaveTxsDownloaded()));
         // nHeight must be consistent.
         assert(pindex->nHeight == nHeight);
         // For every block except the genesis block, the chainwork must be
         // larger than the parent's.
         assert(pindex->pprev == nullptr ||
                pindex->nChainWork >= pindex->pprev->nChainWork);
         // The pskip pointer must point back for all but the first 2 blocks.
         assert(nHeight < 2 ||
                (pindex->pskip && (pindex->pskip->nHeight < nHeight)));
         // All m_blockman.m_block_index entries must at least be TREE valid
         assert(pindexFirstNotTreeValid == nullptr);
         if (pindex->nStatus.getValidity() >= BlockValidity::TREE) {
             // TREE valid implies all parents are TREE valid
             assert(pindexFirstNotTreeValid == nullptr);
         }
         if (pindex->nStatus.getValidity() >= BlockValidity::CHAIN) {
             // CHAIN valid implies all parents are CHAIN valid
             assert(pindexFirstNotChainValid == nullptr);
         }
         if (pindex->nStatus.getValidity() >= BlockValidity::SCRIPTS) {
             // SCRIPTS valid implies all parents are SCRIPTS valid
             assert(pindexFirstNotScriptsValid == nullptr);
         }
         if (pindexFirstInvalid == nullptr) {
             // Checks for not-invalid blocks.
             // The failed mask cannot be set for blocks without invalid parents.
             assert(!pindex->nStatus.isInvalid());
         }
         if (pindexFirstParked == nullptr) {
             // Checks for not-parked blocks.
             // The parked mask cannot be set for blocks without parked parents.
             // (i.e., hasParkedParent only if an ancestor is properly parked).
             assert(!pindex->nStatus.isOnParkedChain());
         }
         if (!CBlockIndexWorkComparator()(pindex, m_chain.Tip()) &&
             pindexFirstNeverProcessed == nullptr) {
             if (pindexFirstInvalid == nullptr) {
                 // Don't perform this check for the background chainstate since
                 // its setBlockIndexCandidates shouldn't have some entries (i.e.
                 // those past the snapshot block) which do exist in the block
                 // index for the active chainstate.
                 if (this == &m_chainman.ActiveChainstate()) {
                     // If this block sorts at least as good as the current tip
                     // and is valid and we have all data for its parents, it
                     // must be in setBlockIndexCandidates or be parked.
                     if (pindexFirstMissing == nullptr) {
                         assert(pindex->nStatus.isOnParkedChain() ||
                                setBlockIndexCandidates.count(pindex));
                     }
                     // m_chain.Tip() must also be there even if some data has
                     // been pruned.
                     if (pindex == m_chain.Tip()) {
                         assert(setBlockIndexCandidates.count(pindex));
                     }
                 }
                 // If some parent is missing, then it could be that this block
                 // was in setBlockIndexCandidates but had to be removed because
                 // of the missing data. In this case it must be in
                 // m_blocks_unlinked -- see test below.
             }
         } else {
             // If this block sorts worse than the current tip or some ancestor's
             // block has never been seen, it cannot be in
             // setBlockIndexCandidates.
             assert(setBlockIndexCandidates.count(pindex) == 0);
         }
         // Check whether this block is in m_blocks_unlinked.
         std::pair<std::multimap<CBlockIndex *, CBlockIndex *>::iterator,
                   std::multimap<CBlockIndex *, CBlockIndex *>::iterator>
             rangeUnlinked =
                 m_blockman.m_blocks_unlinked.equal_range(pindex->pprev);
         bool foundInUnlinked = false;
         while (rangeUnlinked.first != rangeUnlinked.second) {
             assert(rangeUnlinked.first->first == pindex->pprev);
             if (rangeUnlinked.first->second == pindex) {
                 foundInUnlinked = true;
                 break;
             }
             rangeUnlinked.first++;
         }
         if (pindex->pprev && pindex->nStatus.hasData() &&
             pindexFirstNeverProcessed != nullptr &&
             pindexFirstInvalid == nullptr) {
             // If this block has block data available, some parent was never
             // received, and has no invalid parents, it must be in
             // m_blocks_unlinked.
             assert(foundInUnlinked);
         }
         if (!pindex->nStatus.hasData()) {
             // Can't be in m_blocks_unlinked if we don't HAVE_DATA
             assert(!foundInUnlinked);
         }
         if (pindexFirstMissing == nullptr) {
             // We aren't missing data for any parent -- cannot be in
             // m_blocks_unlinked.
             assert(!foundInUnlinked);
         }
         if (pindex->pprev && pindex->nStatus.hasData() &&
             pindexFirstNeverProcessed == nullptr &&
             pindexFirstMissing != nullptr) {
             // We HAVE_DATA for this block, have received data for all parents
             // at some point, but we're currently missing data for some parent.
             // We must have pruned.
             assert(m_blockman.m_have_pruned);
             // This block may have entered m_blocks_unlinked if:
             //  - it has a descendant that at some point had more work than the
             //    tip, and
             //  - we tried switching to that descendant but were missing
             //    data for some intermediate block between m_chain and the
             //    tip.
             // So if this block is itself better than m_chain.Tip() and it
             // wasn't in
             // setBlockIndexCandidates, then it must be in m_blocks_unlinked.
             if (!CBlockIndexWorkComparator()(pindex, m_chain.Tip()) &&
                 setBlockIndexCandidates.count(pindex) == 0) {
                 if (pindexFirstInvalid == nullptr) {
                     assert(foundInUnlinked);
                 }
             }
         }
         // Perhaps too slow
         // assert(pindex->GetBlockHash() == pindex->GetBlockHeader().GetHash());
         // End: actual consistency checks.
 
         // Try descending into the first subnode.
         std::pair<std::multimap<CBlockIndex *, CBlockIndex *>::iterator,
                   std::multimap<CBlockIndex *, CBlockIndex *>::iterator>
             range = forward.equal_range(pindex);
         if (range.first != range.second) {
             // A subnode was found.
             pindex = range.first->second;
             nHeight++;
             continue;
         }
         // This is a leaf node. Move upwards until we reach a node of which we
         // have not yet visited the last child.
         while (pindex) {
             // We are going to either move to a parent or a sibling of pindex.
             // If pindex was the first with a certain property, unset the
             // corresponding variable.
             if (pindex == pindexFirstInvalid) {
                 pindexFirstInvalid = nullptr;
             }
             if (pindex == pindexFirstParked) {
                 pindexFirstParked = nullptr;
             }
             if (pindex == pindexFirstMissing) {
                 pindexFirstMissing = nullptr;
             }
             if (pindex == pindexFirstNeverProcessed) {
                 pindexFirstNeverProcessed = nullptr;
             }
             if (pindex == pindexFirstNotTreeValid) {
                 pindexFirstNotTreeValid = nullptr;
             }
             if (pindex == pindexFirstNotTransactionsValid) {
                 pindexFirstNotTransactionsValid = nullptr;
             }
             if (pindex == pindexFirstNotChainValid) {
                 pindexFirstNotChainValid = nullptr;
             }
             if (pindex == pindexFirstNotScriptsValid) {
                 pindexFirstNotScriptsValid = nullptr;
             }
             // Find our parent.
             CBlockIndex *pindexPar = pindex->pprev;
             // Find which child we just visited.
             std::pair<std::multimap<CBlockIndex *, CBlockIndex *>::iterator,
                       std::multimap<CBlockIndex *, CBlockIndex *>::iterator>
                 rangePar = forward.equal_range(pindexPar);
             while (rangePar.first->second != pindex) {
                 // Our parent must have at least the node we're coming from as
                 // child.
                 assert(rangePar.first != rangePar.second);
                 rangePar.first++;
             }
             // Proceed to the next one.
             rangePar.first++;
             if (rangePar.first != rangePar.second) {
                 // Move to the sibling.
                 pindex = rangePar.first->second;
                 break;
             } else {
                 // Move up further.
                 pindex = pindexPar;
                 nHeight--;
                 continue;
             }
         }
     }
 
     // Check that we actually traversed the entire map.
     assert(nNodes == forward.size());
 }
 
 std::string Chainstate::ToString() {
     AssertLockHeld(::cs_main);
     CBlockIndex *tip = m_chain.Tip();
     return strprintf("Chainstate [%s] @ height %d (%s)",
                      m_from_snapshot_blockhash ? "snapshot" : "ibd",
                      tip ? tip->nHeight : -1,
                      tip ? tip->GetBlockHash().ToString() : "null");
 }
 
 bool Chainstate::ResizeCoinsCaches(size_t coinstip_size, size_t coinsdb_size) {
     AssertLockHeld(::cs_main);
     if (coinstip_size == m_coinstip_cache_size_bytes &&
         coinsdb_size == m_coinsdb_cache_size_bytes) {
         // Cache sizes are unchanged, no need to continue.
         return true;
     }
     size_t old_coinstip_size = m_coinstip_cache_size_bytes;
     m_coinstip_cache_size_bytes = coinstip_size;
     m_coinsdb_cache_size_bytes = coinsdb_size;
     CoinsDB().ResizeCache(coinsdb_size);
 
     LogPrintf("[%s] resized coinsdb cache to %.1f MiB\n", this->ToString(),
               coinsdb_size * (1.0 / 1024 / 1024));
     LogPrintf("[%s] resized coinstip cache to %.1f MiB\n", this->ToString(),
               coinstip_size * (1.0 / 1024 / 1024));
 
     BlockValidationState state;
     bool ret;
 
     if (coinstip_size > old_coinstip_size) {
         // Likely no need to flush if cache sizes have grown.
         ret = FlushStateToDisk(state, FlushStateMode::IF_NEEDED);
     } else {
         // Otherwise, flush state to disk and deallocate the in-memory coins
         // map.
         ret = FlushStateToDisk(state, FlushStateMode::ALWAYS);
         CoinsTip().ReallocateCache();
     }
     return ret;
 }
 
 //! Guess how far we are in the verification process at the given block index
 //! require cs_main if pindex has not been validated yet (because the chain's
 //! transaction count might be unset) This conditional lock requirement might be
 //! confusing, see: https://github.com/bitcoin/bitcoin/issues/15994
 double GuessVerificationProgress(const ChainTxData &data,
                                  const CBlockIndex *pindex) {
     if (pindex == nullptr) {
         return 0.0;
     }
 
     int64_t nNow = time(nullptr);
 
     double fTxTotal;
     if (pindex->GetChainTxCount() <= data.nTxCount) {
         fTxTotal = data.nTxCount + (nNow - data.nTime) * data.dTxRate;
     } else {
         fTxTotal = pindex->GetChainTxCount() +
                    (nNow - pindex->GetBlockTime()) * data.dTxRate;
     }
 
     return std::min<double>(pindex->GetChainTxCount() / fTxTotal, 1.0);
 }
 
 std::optional<BlockHash> ChainstateManager::SnapshotBlockhash() const {
     LOCK(::cs_main);
     if (m_active_chainstate && m_active_chainstate->m_from_snapshot_blockhash) {
         // If a snapshot chainstate exists, it will always be our active.
         return m_active_chainstate->m_from_snapshot_blockhash;
     }
     return std::nullopt;
 }
 
 std::vector<Chainstate *> ChainstateManager::GetAll() {
     LOCK(::cs_main);
     std::vector<Chainstate *> out;
 
     for (Chainstate *pchainstate :
          {m_ibd_chainstate.get(), m_snapshot_chainstate.get()}) {
         if (this->IsUsable(pchainstate)) {
             out.push_back(pchainstate);
         }
     }
 
     return out;
 }
 
 Chainstate &ChainstateManager::InitializeChainstate(CTxMemPool *mempool) {
     AssertLockHeld(::cs_main);
     assert(!m_ibd_chainstate);
     assert(!m_active_chainstate);
 
     m_ibd_chainstate = std::make_unique<Chainstate>(mempool, m_blockman, *this);
     m_active_chainstate = m_ibd_chainstate.get();
     return *m_active_chainstate;
 }
 
 const AssumeutxoData *ExpectedAssumeutxo(const int height,
                                          const CChainParams &chainparams) {
     const MapAssumeutxo &valid_assumeutxos_map = chainparams.Assumeutxo();
     const auto assumeutxo_found = valid_assumeutxos_map.find(height);
 
     if (assumeutxo_found != valid_assumeutxos_map.end()) {
         return &assumeutxo_found->second;
     }
     return nullptr;
 }
 
 static bool DeleteCoinsDBFromDisk(const fs::path &db_path, bool is_snapshot)
     EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {
     AssertLockHeld(::cs_main);
 
     if (is_snapshot) {
         fs::path base_blockhash_path =
             db_path / node::SNAPSHOT_BLOCKHASH_FILENAME;
 
         try {
             const bool existed{fs::remove(base_blockhash_path)};
             if (!existed) {
                 LogPrintf("[snapshot] snapshot chainstate dir being removed "
                           "lacks %s file\n",
                           fs::PathToString(node::SNAPSHOT_BLOCKHASH_FILENAME));
             }
         } catch (const fs::filesystem_error &e) {
             LogPrintf("[snapshot] failed to remove file %s: %s\n",
                       fs::PathToString(base_blockhash_path),
                       fsbridge::get_filesystem_error_message(e));
         }
     }
 
     std::string path_str = fs::PathToString(db_path);
     LogPrintf("Removing leveldb dir at %s\n", path_str);
 
     // We have to destruct before this call leveldb::DB in order to release the
     // db lock, otherwise `DestroyDB` will fail. See `leveldb::~DBImpl()`.
     const bool destroyed = dbwrapper::DestroyDB(path_str, {}).ok();
 
     if (!destroyed) {
         LogPrintf("error: leveldb DestroyDB call failed on %s\n", path_str);
     }
 
     // Datadir should be removed from filesystem; otherwise initialization may
     // detect it on subsequent statups and get confused.
     //
     // If the base_blockhash_path removal above fails in the case of snapshot
     // chainstates, this will return false since leveldb won't remove a
     // non-empty directory.
     return destroyed && !fs::exists(db_path);
 }
 
 bool ChainstateManager::ActivateSnapshot(AutoFile &coins_file,
                                          const SnapshotMetadata &metadata,
                                          bool in_memory) {
     BlockHash base_blockhash = metadata.m_base_blockhash;
 
     if (this->SnapshotBlockhash()) {
         LogPrintf("[snapshot] can't activate a snapshot-based chainstate more "
                   "than once\n");
         return false;
     }
 
     int64_t current_coinsdb_cache_size{0};
     int64_t current_coinstip_cache_size{0};
 
     // Cache percentages to allocate to each chainstate.
     //
     // These particular percentages don't matter so much since they will only be
     // relevant during snapshot activation; caches are rebalanced at the
     // conclusion of this function. We want to give (essentially) all available
     // cache capacity to the snapshot to aid the bulk load later in this
     // function.
     static constexpr double IBD_CACHE_PERC = 0.01;
     static constexpr double SNAPSHOT_CACHE_PERC = 0.99;
 
     {
         LOCK(::cs_main);
         // Resize the coins caches to ensure we're not exceeding memory limits.
         //
         // Allocate the majority of the cache to the incoming snapshot
         // chainstate, since (optimistically) getting to its tip will be the top
         // priority. We'll need to call `MaybeRebalanceCaches()` once we're done
         // with this function to ensure the right allocation (including the
         // possibility that no snapshot was activated and that we should restore
         // the active chainstate caches to their original size).
         //
         current_coinsdb_cache_size =
             this->ActiveChainstate().m_coinsdb_cache_size_bytes;
         current_coinstip_cache_size =
             this->ActiveChainstate().m_coinstip_cache_size_bytes;
 
         // Temporarily resize the active coins cache to make room for the
         // newly-created snapshot chain.
         this->ActiveChainstate().ResizeCoinsCaches(
             static_cast<size_t>(current_coinstip_cache_size * IBD_CACHE_PERC),
             static_cast<size_t>(current_coinsdb_cache_size * IBD_CACHE_PERC));
     }
 
     auto snapshot_chainstate =
         WITH_LOCK(::cs_main, return std::make_unique<Chainstate>(
                                  /* mempool */ nullptr, m_blockman, *this,
                                  base_blockhash));
 
     {
         LOCK(::cs_main);
         snapshot_chainstate->InitCoinsDB(
             static_cast<size_t>(current_coinsdb_cache_size *
                                 SNAPSHOT_CACHE_PERC),
             in_memory, false, "chainstate");
         snapshot_chainstate->InitCoinsCache(static_cast<size_t>(
             current_coinstip_cache_size * SNAPSHOT_CACHE_PERC));
     }
 
     bool snapshot_ok = this->PopulateAndValidateSnapshot(*snapshot_chainstate,
                                                          coins_file, metadata);
 
     // If not in-memory, persist the base blockhash for use during subsequent
     // initialization.
     if (!in_memory) {
         LOCK(::cs_main);
         if (!node::WriteSnapshotBaseBlockhash(*snapshot_chainstate)) {
             snapshot_ok = false;
         }
     }
     if (!snapshot_ok) {
         LOCK(::cs_main);
         this->MaybeRebalanceCaches();
 
         // PopulateAndValidateSnapshot can return (in error) before the leveldb
         // datadir has been created, so only attempt removal if we got that far.
         if (auto snapshot_datadir = node::FindSnapshotChainstateDir()) {
             // We have to destruct leveldb::DB in order to release the db lock,
             // otherwise DestroyDB() (in DeleteCoinsDBFromDisk()) will fail. See
             // `leveldb::~DBImpl()`. Destructing the chainstate (and so
             // resetting the coinsviews object) does this.
             snapshot_chainstate.reset();
             bool removed =
                 DeleteCoinsDBFromDisk(*snapshot_datadir, /*is_snapshot=*/true);
             if (!removed) {
                 AbortNode(
                     strprintf("Failed to remove snapshot chainstate dir (%s). "
                               "Manually remove it before restarting.\n",
                               fs::PathToString(*snapshot_datadir)));
             }
         }
         return false;
     }
 
     {
         LOCK(::cs_main);
         assert(!m_snapshot_chainstate);
         m_snapshot_chainstate.swap(snapshot_chainstate);
         const bool chaintip_loaded = m_snapshot_chainstate->LoadChainTip();
         assert(chaintip_loaded);
 
         m_active_chainstate = m_snapshot_chainstate.get();
 
         LogPrintf("[snapshot] successfully activated snapshot %s\n",
                   base_blockhash.ToString());
         LogPrintf("[snapshot] (%.2f MB)\n",
                   m_snapshot_chainstate->CoinsTip().DynamicMemoryUsage() /
                       (1000 * 1000));
 
         this->MaybeRebalanceCaches();
     }
     return true;
 }
 
 static void FlushSnapshotToDisk(CCoinsViewCache &coins_cache,
                                 bool snapshot_loaded) {
     LOG_TIME_MILLIS_WITH_CATEGORY_MSG_ONCE(
         strprintf("%s (%.2f MB)",
                   snapshot_loaded ? "saving snapshot chainstate"
                                   : "flushing coins cache",
                   coins_cache.DynamicMemoryUsage() / (1000 * 1000)),
         BCLog::LogFlags::ALL);
 
     coins_cache.Flush();
 }
 
 struct StopHashingException : public std::exception {
     const char *what() const throw() override {
         return "ComputeUTXOStats interrupted by shutdown.";
     }
 };
 
 static void SnapshotUTXOHashBreakpoint() {
     if (ShutdownRequested()) {
         throw StopHashingException();
     }
 }
 
 bool ChainstateManager::PopulateAndValidateSnapshot(
     Chainstate &snapshot_chainstate, AutoFile &coins_file,
     const SnapshotMetadata &metadata) {
     // It's okay to release cs_main before we're done using `coins_cache`
     // because we know that nothing else will be referencing the newly created
     // snapshot_chainstate yet.
     CCoinsViewCache &coins_cache =
         *WITH_LOCK(::cs_main, return &snapshot_chainstate.CoinsTip());
 
     BlockHash base_blockhash = metadata.m_base_blockhash;
 
     CBlockIndex *snapshot_start_block = WITH_LOCK(
         ::cs_main, return m_blockman.LookupBlockIndex(base_blockhash));
 
     if (!snapshot_start_block) {
         // Needed for ComputeUTXOStats and ExpectedAssumeutxo to determine the
         // height and to avoid a crash when base_blockhash.IsNull()
         LogPrintf("[snapshot] Did not find snapshot start blockheader %s\n",
                   base_blockhash.ToString());
         return false;
     }
 
     int base_height = snapshot_start_block->nHeight;
     auto maybe_au_data = ExpectedAssumeutxo(base_height, GetParams());
 
     if (!maybe_au_data) {
         LogPrintf("[snapshot] assumeutxo height in snapshot metadata not "
                   "recognized (%d) - refusing to load snapshot\n",
                   base_height);
         return false;
     }
 
     const AssumeutxoData &au_data = *maybe_au_data;
 
     COutPoint outpoint;
     Coin coin;
     const uint64_t coins_count = metadata.m_coins_count;
     uint64_t coins_left = metadata.m_coins_count;
 
     LogPrintf("[snapshot] loading coins from snapshot %s\n",
               base_blockhash.ToString());
     int64_t coins_processed{0};
 
     while (coins_left > 0) {
         try {
             coins_file >> outpoint;
             coins_file >> coin;
         } catch (const std::ios_base::failure &) {
             LogPrintf("[snapshot] bad snapshot format or truncated snapshot "
                       "after deserializing %d coins\n",
                       coins_count - coins_left);
             return false;
         }
         if (coin.GetHeight() > uint32_t(base_height) ||
             // Avoid integer wrap-around in coinstats.cpp:ApplyHash
             outpoint.GetN() >=
                 std::numeric_limits<decltype(outpoint.GetN())>::max()) {
             LogPrintf(
                 "[snapshot] bad snapshot data after deserializing %d coins\n",
                 coins_count - coins_left);
             return false;
         }
         coins_cache.EmplaceCoinInternalDANGER(std::move(outpoint),
                                               std::move(coin));
 
         --coins_left;
         ++coins_processed;
 
         if (coins_processed % 1000000 == 0) {
             LogPrintf("[snapshot] %d coins loaded (%.2f%%, %.2f MB)\n",
                       coins_processed,
                       static_cast<float>(coins_processed) * 100 /
                           static_cast<float>(coins_count),
                       coins_cache.DynamicMemoryUsage() / (1000 * 1000));
         }
 
         // Batch write and flush (if we need to) every so often.
         //
         // If our average Coin size is roughly 41 bytes, checking every 120,000
         // coins means <5MB of memory imprecision.
         if (coins_processed % 120000 == 0) {
             if (ShutdownRequested()) {
                 return false;
             }
 
             const auto snapshot_cache_state = WITH_LOCK(
                 ::cs_main, return snapshot_chainstate.GetCoinsCacheSizeState());
 
             if (snapshot_cache_state >= CoinsCacheSizeState::CRITICAL) {
                 // This is a hack - we don't know what the actual best block is,
                 // but that doesn't matter for the purposes of flushing the
                 // cache here. We'll set this to its correct value
                 // (`base_blockhash`) below after the coins are loaded.
                 coins_cache.SetBestBlock(BlockHash{GetRandHash()});
 
                 // No need to acquire cs_main since this chainstate isn't being
                 // used yet.
                 FlushSnapshotToDisk(coins_cache, /*snapshot_loaded=*/false);
             }
         }
     }
 
     // Important that we set this. This and the coins_cache accesses above are
     // sort of a layer violation, but either we reach into the innards of
     // CCoinsViewCache here or we have to invert some of the Chainstate to
     // embed them in a snapshot-activation-specific CCoinsViewCache bulk load
     // method.
     coins_cache.SetBestBlock(base_blockhash);
 
     bool out_of_coins{false};
     try {
         coins_file >> outpoint;
     } catch (const std::ios_base::failure &) {
         // We expect an exception since we should be out of coins.
         out_of_coins = true;
     }
     if (!out_of_coins) {
         LogPrintf("[snapshot] bad snapshot - coins left over after "
                   "deserializing %d coins\n",
                   coins_count);
         return false;
     }
 
     LogPrintf("[snapshot] loaded %d (%.2f MB) coins from snapshot %s\n",
               coins_count, coins_cache.DynamicMemoryUsage() / (1000 * 1000),
               base_blockhash.ToString());
 
     // No need to acquire cs_main since this chainstate isn't being used yet.
     FlushSnapshotToDisk(coins_cache, /*snapshot_loaded=*/true);
 
     assert(coins_cache.GetBestBlock() == base_blockhash);
 
     // As above, okay to immediately release cs_main here since no other context
     // knows about the snapshot_chainstate.
     CCoinsViewDB *snapshot_coinsdb =
         WITH_LOCK(::cs_main, return &snapshot_chainstate.CoinsDB());
 
     std::optional<CCoinsStats> maybe_stats;
 
     try {
         maybe_stats = ComputeUTXOStats(CoinStatsHashType::HASH_SERIALIZED,
                                        snapshot_coinsdb, m_blockman,
                                        SnapshotUTXOHashBreakpoint);
     } catch (StopHashingException const &) {
         return false;
     }
     if (!maybe_stats.has_value()) {
         LogPrintf("[snapshot] failed to generate coins stats\n");
         return false;
     }
 
     // Assert that the deserialized chainstate contents match the expected
     // assumeutxo value.
     if (AssumeutxoHash{maybe_stats->hashSerialized} !=
         au_data.hash_serialized) {
         LogPrintf("[snapshot] bad snapshot content hash: expected %s, got %s\n",
                   au_data.hash_serialized.ToString(),
                   maybe_stats->hashSerialized.ToString());
         return false;
     }
 
     snapshot_chainstate.m_chain.SetTip(snapshot_start_block);
 
     // The remainder of this function requires modifying data protected by
     // cs_main.
     LOCK(::cs_main);
 
     // Fake various pieces of CBlockIndex state:
     CBlockIndex *index = nullptr;
 
     // Don't make any modifications to the genesis block.
     // This is especially important because we don't want to erroneously
     // apply ASSUMED_VALID_FLAG to genesis, which would happen if we didn't
     // skip it here (since it apparently isn't BlockValidity::SCRIPTS).
     constexpr int AFTER_GENESIS_START{1};
 
     for (int i = AFTER_GENESIS_START; i <= snapshot_chainstate.m_chain.Height();
          ++i) {
         index = snapshot_chainstate.m_chain[i];
 
         // Fake nTx so that LoadBlockIndex() loads assumed-valid CBlockIndex
         // entries (among other things)
         if (!index->nTx) {
             index->nTx = 1;
         }
         // Fake nChainTx so that GuessVerificationProgress reports accurately
         index->nChainTx = index->pprev->nChainTx + index->nTx;
 
         // Mark unvalidated block index entries beneath the snapshot base block
         // as assumed-valid.
         if (!index->IsValid(BlockValidity::SCRIPTS)) {
             // This flag will be removed once the block is fully validated by a
             // background chainstate.
             index->nStatus = index->nStatus.withAssumedValid();
         }
 
         m_blockman.m_dirty_blockindex.insert(index);
         // Changes to the block index will be flushed to disk after this call
         // returns in `ActivateSnapshot()`, when `MaybeRebalanceCaches()` is
         // called, since we've added a snapshot chainstate and therefore will
         // have to downsize the IBD chainstate, which will result in a call to
         // `FlushStateToDisk(ALWAYS)`.
     }
 
     assert(index);
     index->nChainTx = au_data.nChainTx;
     snapshot_chainstate.setBlockIndexCandidates.insert(snapshot_start_block);
 
     LogPrintf("[snapshot] validated snapshot (%.2f MB)\n",
               coins_cache.DynamicMemoryUsage() / (1000 * 1000));
     return true;
 }
 
 // Currently, this function holds cs_main for its duration, which could be for
 // multiple minutes due to the ComputeUTXOStats call. This hold is necessary
 // because we need to avoid advancing the background validation chainstate
 // farther than the snapshot base block - and this function is also invoked
 // from within ConnectTip, i.e. from within ActivateBestChain, so cs_main is
 // held anyway.
 //
 // Eventually (TODO), we could somehow separate this function's runtime from
 // maintenance of the active chain, but that will either require
 //
 //  (i) setting `m_disabled` immediately and ensuring all chainstate accesses go
 //      through IsUsable() checks, or
 //
 //  (ii) giving each chainstate its own lock instead of using cs_main for
 //  everything.
 SnapshotCompletionResult ChainstateManager::MaybeCompleteSnapshotValidation(
     std::function<void(bilingual_str)> shutdown_fnc) {
     AssertLockHeld(cs_main);
     if (m_ibd_chainstate.get() == &this->ActiveChainstate() ||
         !this->IsUsable(m_snapshot_chainstate.get()) ||
         !this->IsUsable(m_ibd_chainstate.get()) ||
         !m_ibd_chainstate->m_chain.Tip()) {
         // Nothing to do - this function only applies to the background
         // validation chainstate.
         return SnapshotCompletionResult::SKIPPED;
     }
     const int snapshot_tip_height = this->ActiveHeight();
     const int snapshot_base_height = *Assert(this->GetSnapshotBaseHeight());
     const CBlockIndex &index_new = *Assert(m_ibd_chainstate->m_chain.Tip());
 
     if (index_new.nHeight < snapshot_base_height) {
         // Background IBD not complete yet.
         return SnapshotCompletionResult::SKIPPED;
     }
 
     assert(SnapshotBlockhash());
     BlockHash snapshot_blockhash = *Assert(SnapshotBlockhash());
 
     auto handle_invalid_snapshot = [&]() EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {
         bilingual_str user_error = strprintf(
             _("%s failed to validate the -assumeutxo snapshot state. "
               "This indicates a hardware problem, or a bug in the software, or "
               "a bad software modification that allowed an invalid snapshot to "
               "be loaded. As a result of this, the node will shut down and "
               "stop using any state that was built on the snapshot, resetting "
               "the chain height from %d to %d. On the next restart, the node "
               "will resume syncing from %d without using any snapshot data. "
               "Please report this incident to %s, including how you obtained "
               "the snapshot. The invalid snapshot chainstate has been left on "
               "disk in case it is helpful in diagnosing the issue that caused "
               "this error."),
             PACKAGE_NAME, snapshot_tip_height, snapshot_base_height,
             snapshot_base_height, PACKAGE_BUGREPORT);
 
         LogPrintf("[snapshot] !!! %s\n", user_error.original);
         LogPrintf("[snapshot] deleting snapshot, reverting to validated chain, "
                   "and stopping node\n");
 
         m_active_chainstate = m_ibd_chainstate.get();
         m_snapshot_chainstate->m_disabled = true;
         assert(!this->IsUsable(m_snapshot_chainstate.get()));
         assert(this->IsUsable(m_ibd_chainstate.get()));
 
         m_snapshot_chainstate->InvalidateCoinsDBOnDisk();
 
         shutdown_fnc(user_error);
     };
 
     if (index_new.GetBlockHash() != snapshot_blockhash) {
         LogPrintf(
             "[snapshot] supposed base block %s does not match the "
             "snapshot base block %s (height %d). Snapshot is not valid.\n",
             index_new.ToString(), snapshot_blockhash.ToString(),
             snapshot_base_height);
         handle_invalid_snapshot();
         return SnapshotCompletionResult::BASE_BLOCKHASH_MISMATCH;
     }
 
     assert(index_new.nHeight == snapshot_base_height);
 
     int curr_height = m_ibd_chainstate->m_chain.Height();
 
     assert(snapshot_base_height == curr_height);
     assert(snapshot_base_height == index_new.nHeight);
     assert(this->IsUsable(m_snapshot_chainstate.get()));
     assert(this->GetAll().size() == 2);
 
     CCoinsViewDB &ibd_coins_db = m_ibd_chainstate->CoinsDB();
     m_ibd_chainstate->ForceFlushStateToDisk();
 
     auto maybe_au_data = ExpectedAssumeutxo(curr_height, GetParams());
     if (!maybe_au_data) {
         LogPrintf("[snapshot] assumeutxo data not found for height "
                   "(%d) - refusing to validate snapshot\n",
                   curr_height);
         handle_invalid_snapshot();
         return SnapshotCompletionResult::MISSING_CHAINPARAMS;
     }
 
     const AssumeutxoData &au_data = *maybe_au_data;
     std::optional<CCoinsStats> maybe_ibd_stats;
     LogPrintf(
         "[snapshot] computing UTXO stats for background chainstate to validate "
         "snapshot - this could take a few minutes\n");
     try {
         maybe_ibd_stats =
             ComputeUTXOStats(CoinStatsHashType::HASH_SERIALIZED, &ibd_coins_db,
                              m_blockman, SnapshotUTXOHashBreakpoint);
     } catch (StopHashingException const &) {
         return SnapshotCompletionResult::STATS_FAILED;
     }
 
     if (!maybe_ibd_stats) {
         LogPrintf(
             "[snapshot] failed to generate stats for validation coins db\n");
         // While this isn't a problem with the snapshot per se, this condition
         // prevents us from validating the snapshot, so we should shut down and
         // let the user handle the issue manually.
         handle_invalid_snapshot();
         return SnapshotCompletionResult::STATS_FAILED;
     }
     const auto &ibd_stats = *maybe_ibd_stats;
 
     // Compare the background validation chainstate's UTXO set hash against the
     // hard-coded assumeutxo hash we expect.
     //
     // TODO: For belt-and-suspenders, we could cache the UTXO set
     // hash for the snapshot when it's loaded in its chainstate's leveldb. We
     // could then reference that here for an additional check.
     if (AssumeutxoHash{ibd_stats.hashSerialized} != au_data.hash_serialized) {
         LogPrintf("[snapshot] hash mismatch: actual=%s, expected=%s\n",
                   ibd_stats.hashSerialized.ToString(),
                   au_data.hash_serialized.ToString());
         handle_invalid_snapshot();
         return SnapshotCompletionResult::HASH_MISMATCH;
     }
 
     LogPrintf("[snapshot] snapshot beginning at %s has been fully validated\n",
               snapshot_blockhash.ToString());
 
     m_ibd_chainstate->m_disabled = true;
     this->MaybeRebalanceCaches();
 
     return SnapshotCompletionResult::SUCCESS;
 }
 
 Chainstate &ChainstateManager::ActiveChainstate() const {
     LOCK(::cs_main);
     assert(m_active_chainstate);
     return *m_active_chainstate;
 }
 
 bool ChainstateManager::IsSnapshotActive() const {
     LOCK(::cs_main);
     return m_snapshot_chainstate &&
            m_active_chainstate == m_snapshot_chainstate.get();
 }
 void ChainstateManager::MaybeRebalanceCaches() {
     AssertLockHeld(::cs_main);
     bool ibd_usable = this->IsUsable(m_ibd_chainstate.get());
     bool snapshot_usable = this->IsUsable(m_snapshot_chainstate.get());
     assert(ibd_usable || snapshot_usable);
 
     if (ibd_usable && !snapshot_usable) {
         LogPrintf("[snapshot] allocating all cache to the IBD chainstate\n");
         // Allocate everything to the IBD chainstate.
         m_ibd_chainstate->ResizeCoinsCaches(m_total_coinstip_cache,
                                             m_total_coinsdb_cache);
     } else if (snapshot_usable && !ibd_usable) {
         // If background validation has completed and snapshot is our active
         // chain...
         LogPrintf(
             "[snapshot] allocating all cache to the snapshot chainstate\n");
         // Allocate everything to the snapshot chainstate.
         m_snapshot_chainstate->ResizeCoinsCaches(m_total_coinstip_cache,
                                                  m_total_coinsdb_cache);
     } else if (ibd_usable && snapshot_usable) {
         // If both chainstates exist, determine who needs more cache based on
         // IBD status.
         //
         // Note: shrink caches first so that we don't inadvertently overwhelm
         // available memory.
         if (m_snapshot_chainstate->IsInitialBlockDownload()) {
             m_ibd_chainstate->ResizeCoinsCaches(m_total_coinstip_cache * 0.05,
                                                 m_total_coinsdb_cache * 0.05);
             m_snapshot_chainstate->ResizeCoinsCaches(
                 m_total_coinstip_cache * 0.95, m_total_coinsdb_cache * 0.95);
         } else {
             m_snapshot_chainstate->ResizeCoinsCaches(
                 m_total_coinstip_cache * 0.05, m_total_coinsdb_cache * 0.05);
             m_ibd_chainstate->ResizeCoinsCaches(m_total_coinstip_cache * 0.95,
                                                 m_total_coinsdb_cache * 0.95);
         }
     }
 }
 
 void ChainstateManager::ResetChainstates() {
     m_ibd_chainstate.reset();
     m_snapshot_chainstate.reset();
     m_active_chainstate = nullptr;
 }
 
 /**
  * Apply default chain params to nullopt members.
  * This helps to avoid coding errors around the accidental use of the compare
  * operators that accept nullopt, thus ignoring the intended default value.
  */
 static ChainstateManager::Options &&Flatten(ChainstateManager::Options &&opts) {
     if (!opts.check_block_index.has_value()) {
         opts.check_block_index =
             opts.config.GetChainParams().DefaultConsistencyChecks();
     }
 
     if (!opts.minimum_chain_work.has_value()) {
         opts.minimum_chain_work = UintToArith256(
             opts.config.GetChainParams().GetConsensus().nMinimumChainWork);
     }
     if (!opts.assumed_valid_block.has_value()) {
         opts.assumed_valid_block =
             opts.config.GetChainParams().GetConsensus().defaultAssumeValid;
     }
     Assert(opts.adjusted_time_callback);
     return std::move(opts);
 }
 
 ChainstateManager::ChainstateManager(Options options)
     : m_options{Flatten(std::move(options))} {}
 
 bool ChainstateManager::DetectSnapshotChainstate(CTxMemPool *mempool) {
     assert(!m_snapshot_chainstate);
     std::optional<fs::path> path = node::FindSnapshotChainstateDir();
     if (!path) {
         return false;
     }
     std::optional<BlockHash> base_blockhash =
         node::ReadSnapshotBaseBlockhash(*path);
     if (!base_blockhash) {
         return false;
     }
     LogPrintf("[snapshot] detected active snapshot chainstate (%s) - loading\n",
               fs::PathToString(*path));
 
     this->ActivateExistingSnapshot(mempool, *base_blockhash);
     return true;
 }
 
 Chainstate &
 ChainstateManager::ActivateExistingSnapshot(CTxMemPool *mempool,
                                             BlockHash base_blockhash) {
     assert(!m_snapshot_chainstate);
     m_snapshot_chainstate = std::make_unique<Chainstate>(mempool, m_blockman,
                                                          *this, base_blockhash);
     LogPrintf("[snapshot] switching active chainstate to %s\n",
               m_snapshot_chainstate->ToString());
     m_active_chainstate = m_snapshot_chainstate.get();
     return *m_snapshot_chainstate;
 }
 
 void Chainstate::InvalidateCoinsDBOnDisk() {
     AssertLockHeld(::cs_main);
     // Should never be called on a non-snapshot chainstate.
     assert(m_from_snapshot_blockhash);
     auto storage_path_maybe = this->CoinsDB().StoragePath();
     // Should never be called with a non-existent storage path.
     assert(storage_path_maybe);
     fs::path snapshot_datadir = *storage_path_maybe;
 
     // Coins views no longer usable.
     m_coins_views.reset();
 
     auto invalid_path = snapshot_datadir + "_INVALID";
     std::string dbpath = fs::PathToString(snapshot_datadir);
     std::string target = fs::PathToString(invalid_path);
     LogPrintf("[snapshot] renaming snapshot datadir %s to %s\n", dbpath,
               target);
 
     // The invalid snapshot datadir is simply moved and not deleted because we
     // may want to do forensics later during issue investigation. The user is
     // instructed accordingly in MaybeCompleteSnapshotValidation().
     try {
         fs::rename(snapshot_datadir, invalid_path);
     } catch (const fs::filesystem_error &e) {
         auto src_str = fs::PathToString(snapshot_datadir);
         auto dest_str = fs::PathToString(invalid_path);
 
         LogPrintf("%s: error renaming file '%s' -> '%s': %s\n", __func__,
                   src_str, dest_str, e.what());
         AbortNode(strprintf("Rename of '%s' -> '%s' failed. "
                             "You should resolve this by manually moving or "
                             "deleting the invalid "
                             "snapshot directory %s, otherwise you will "
                             "encounter the same error again "
                             "on the next startup.",
                             src_str, dest_str, src_str));
     }
 }
 
 const CBlockIndex *ChainstateManager::GetSnapshotBaseBlock() const {
     const auto blockhash_op = this->SnapshotBlockhash();
     if (!blockhash_op) {
         return nullptr;
     }
     return Assert(m_blockman.LookupBlockIndex(*blockhash_op));
 }
 
 std::optional<int> ChainstateManager::GetSnapshotBaseHeight() const {
     const CBlockIndex *base = this->GetSnapshotBaseBlock();
     return base ? std::make_optional(base->nHeight) : std::nullopt;
 }
 
 bool ChainstateManager::ValidatedSnapshotCleanup() {
     AssertLockHeld(::cs_main);
     auto get_storage_path = [](auto &chainstate) EXCLUSIVE_LOCKS_REQUIRED(
                                 ::cs_main) -> std::optional<fs::path> {
         if (!(chainstate && chainstate->HasCoinsViews())) {
             return {};
         }
         return chainstate->CoinsDB().StoragePath();
     };
     std::optional<fs::path> ibd_chainstate_path_maybe =
         get_storage_path(m_ibd_chainstate);
     std::optional<fs::path> snapshot_chainstate_path_maybe =
         get_storage_path(m_snapshot_chainstate);
 
     if (!this->IsSnapshotValidated()) {
         // No need to clean up.
         return false;
     }
     // If either path doesn't exist, that means at least one of the chainstates
     // is in-memory, in which case we can't do on-disk cleanup. You'd better be
     // in a unittest!
     if (!ibd_chainstate_path_maybe || !snapshot_chainstate_path_maybe) {
         LogPrintf("[snapshot] snapshot chainstate cleanup cannot happen with "
                   "in-memory chainstates. You are testing, right?\n");
         return false;
     }
 
     const auto &snapshot_chainstate_path = *snapshot_chainstate_path_maybe;
     const auto &ibd_chainstate_path = *ibd_chainstate_path_maybe;
 
     // Since we're going to be moving around the underlying leveldb filesystem
     // content for each chainstate, make sure that the chainstates (and their
     // constituent CoinsViews members) have been destructed first.
     //
     // The caller of this method will be responsible for reinitializing
     // chainstates if they want to continue operation.
     this->ResetChainstates();
 
     // No chainstates should be considered usable.
     assert(this->GetAll().size() == 0);
 
     LogPrintf("[snapshot] deleting background chainstate directory (now "
               "unnecessary) (%s)\n",
               fs::PathToString(ibd_chainstate_path));
 
     fs::path tmp_old{ibd_chainstate_path + "_todelete"};
 
     auto rename_failed_abort = [](fs::path p_old, fs::path p_new,
                                   const fs::filesystem_error &err) {
         LogPrintf("Error renaming file (%s): %s\n", fs::PathToString(p_old),
                   err.what());
         AbortNode(strprintf(
             "Rename of '%s' -> '%s' failed. "
             "Cannot clean up the background chainstate leveldb directory.",
             fs::PathToString(p_old), fs::PathToString(p_new)));
     };
 
     try {
         fs::rename(ibd_chainstate_path, tmp_old);
     } catch (const fs::filesystem_error &e) {
         rename_failed_abort(ibd_chainstate_path, tmp_old, e);
         throw;
     }
 
     LogPrintf("[snapshot] moving snapshot chainstate (%s) to "
               "default chainstate directory (%s)\n",
               fs::PathToString(snapshot_chainstate_path),
               fs::PathToString(ibd_chainstate_path));
 
     try {
         fs::rename(snapshot_chainstate_path, ibd_chainstate_path);
     } catch (const fs::filesystem_error &e) {
         rename_failed_abort(snapshot_chainstate_path, ibd_chainstate_path, e);
         throw;
     }
 
     if (!DeleteCoinsDBFromDisk(tmp_old, /*is_snapshot=*/false)) {
         // No need to AbortNode because once the unneeded bg chainstate data is
         // moved, it will not interfere with subsequent initialization.
         LogPrintf("Deletion of %s failed. Please remove it manually, as the "
                   "directory is now unnecessary.\n",
                   fs::PathToString(tmp_old));
     } else {
         LogPrintf("[snapshot] deleted background chainstate directory (%s)\n",
                   fs::PathToString(ibd_chainstate_path));
     }
     return true;
 }
diff --git a/src/validation.h b/src/validation.h
index 61abf492d..5a4e88618 100644
--- a/src/validation.h
+++ b/src/validation.h
@@ -1,1503 +1,1504 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2019 The Bitcoin Core developers
 // Copyright (c) 2017-2020 The Bitcoin developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_VALIDATION_H
 #define BITCOIN_VALIDATION_H
 
 #if defined(HAVE_CONFIG_H)
 #include <config/bitcoin-config.h>
 #endif
 
 #include <arith_uint256.h>
 #include <attributes.h>
 #include <blockfileinfo.h>
 #include <blockindexcomparators.h>
 #include <bloom.h>
 #include <chain.h>
 #include <chainparams.h>
 #include <config.h>
 #include <consensus/amount.h>
 #include <consensus/consensus.h>
 #include <deploymentstatus.h>
 #include <disconnectresult.h>
 #include <flatfile.h>
 #include <fs.h>
 #include <kernel/chainstatemanager_opts.h>
 #include <kernel/cs_main.h>
 #include <node/blockstorage.h>
 #include <policy/packages.h>
 #include <script/script_error.h>
 #include <script/script_metrics.h>
 #include <shutdown.h>
 #include <sync.h>
 #include <txdb.h>
 #include <txmempool.h> // For CTxMemPool::cs
 #include <uint256.h>
 #include <util/check.h>
 #include <util/translation.h>
 
 #include <atomic>
 #include <cstdint>
 #include <map>
 #include <memory>
 #include <optional>
 #include <set>
 #include <string>
 #include <thread>
 #include <utility>
 #include <vector>
 
 class BlockPolicyValidationState;
 class CChainParams;
 class Chainstate;
 class ChainstateManager;
 class CScriptCheck;
 class CTxMemPool;
 class CTxUndo;
 class DisconnectedBlockTransactions;
 
 struct ChainTxData;
 struct FlatFilePos;
 struct PrecomputedTransactionData;
 struct LockPoints;
 struct AssumeutxoData;
 namespace node {
 class SnapshotMetadata;
 } // namespace node
 namespace Consensus {
 struct Params;
 } // namespace Consensus
 
 namespace Consensus {
 struct Params;
 }
 
 #define MIN_TRANSACTION_SIZE                                                   \
     (::GetSerializeSize(CTransaction(), PROTOCOL_VERSION))
 
 /** Maximum number of dedicated script-checking threads allowed */
 static const int MAX_SCRIPTCHECK_THREADS = 15;
 /** -par default (number of script-checking threads, 0 = auto) */
 static const int DEFAULT_SCRIPTCHECK_THREADS = 0;
 
 static const bool DEFAULT_PEERBLOOMFILTERS = true;
 
 /** Default for -stopatheight */
 static const int DEFAULT_STOPATHEIGHT = 0;
 /**
  * Block files containing a block-height within MIN_BLOCKS_TO_KEEP of
  * ActiveChain().Tip() will not be pruned.
  */
 static const unsigned int MIN_BLOCKS_TO_KEEP = 288;
 static const signed int DEFAULT_CHECKBLOCKS = 6;
 static const unsigned int DEFAULT_CHECKLEVEL = 3;
 /**
  * Require that user allocate at least 550 MiB for block & undo files
  * (blk???.dat and rev???.dat)
  * At 1MB per block, 288 blocks = 288MB.
  * Add 15% for Undo data = 331MB
  * Add 20% for Orphan block rate = 397MB
  * We want the low water mark after pruning to be at least 397 MB and since we
  * prune in full block file chunks, we need the high water mark which triggers
  * the prune to be one 128MB block file + added 15% undo data = 147MB greater
  * for a total of 545MB
  * Setting the target to >= 550 MiB will make it likely we can respect the
  * target.
  */
 static const uint64_t MIN_DISK_SPACE_FOR_BLOCK_FILES = 550 * 1024 * 1024;
 
 /** Current sync state passed to tip changed callbacks. */
 enum class SynchronizationState { INIT_REINDEX, INIT_DOWNLOAD, POST_INIT };
 
 extern GlobalMutex g_best_block_mutex;
 extern std::condition_variable g_best_block_cv;
 /** Used to notify getblocktemplate RPC of new tips. */
 extern uint256 g_best_block;
 
 /** Documentation for argument 'checklevel'. */
 extern const std::vector<std::string> CHECKLEVEL_DOC;
 
 class BlockValidationOptions {
 private:
     uint64_t excessiveBlockSize;
     bool checkPoW : 1;
     bool checkMerkleRoot : 1;
 
 public:
     // Do full validation by default
     explicit BlockValidationOptions(const Config &config);
     explicit BlockValidationOptions(uint64_t _excessiveBlockSize,
                                     bool _checkPow = true,
                                     bool _checkMerkleRoot = true)
         : excessiveBlockSize(_excessiveBlockSize), checkPoW(_checkPow),
           checkMerkleRoot(_checkMerkleRoot) {}
 
     BlockValidationOptions withCheckPoW(bool _checkPoW = true) const {
         BlockValidationOptions ret = *this;
         ret.checkPoW = _checkPoW;
         return ret;
     }
 
     BlockValidationOptions
     withCheckMerkleRoot(bool _checkMerkleRoot = true) const {
         BlockValidationOptions ret = *this;
         ret.checkMerkleRoot = _checkMerkleRoot;
         return ret;
     }
 
     bool shouldValidatePoW() const { return checkPoW; }
     bool shouldValidateMerkleRoot() const { return checkMerkleRoot; }
     uint64_t getExcessiveBlockSize() const { return excessiveBlockSize; }
 };
 
 /**
  * Run instances of script checking worker threads
  */
 void StartScriptCheckWorkerThreads(int threads_num);
 
 /**
  * Stop all of the script checking worker threads
  */
 void StopScriptCheckWorkerThreads();
 
 Amount GetBlockSubsidy(int nHeight, const Consensus::Params &consensusParams);
 
 bool AbortNode(BlockValidationState &state, const std::string &strMessage,
                const bilingual_str &userMessage = bilingual_str{});
 
 /**
  * Guess verification progress (as a fraction between 0.0=genesis and
  * 1.0=current tip).
  */
 double GuessVerificationProgress(const ChainTxData &data,
                                  const CBlockIndex *pindex);
 
 /** Prune block files up to a given height */
 void PruneBlockFilesManual(Chainstate &active_chainstate,
                            int nManualPruneHeight);
 
 /**
  * Validation result for a single transaction mempool acceptance.
  */
 struct MempoolAcceptResult {
     /** Used to indicate the results of mempool validation. */
     enum class ResultType {
         //! Fully validated, valid.
         VALID,
         //! Invalid.
         INVALID,
         //! Valid, transaction was already in the mempool.
         MEMPOOL_ENTRY,
     };
     const ResultType m_result_type;
     const TxValidationState m_state;
 
     // The following fields are only present when m_result_type =
     // ResultType::VALID or MEMPOOL_ENTRY
     /**
      * Virtual size as used by the mempool, calculated using serialized size
      * and sigchecks.
      */
     const std::optional<int64_t> m_vsize;
     /** Raw base fees in satoshis. */
     const std::optional<Amount> m_base_fees;
     static MempoolAcceptResult Failure(TxValidationState state) {
         return MempoolAcceptResult(state);
     }
 
     /** Constructor for success case */
     static MempoolAcceptResult Success(int64_t vsize, Amount fees) {
         return MempoolAcceptResult(ResultType::VALID, vsize, fees);
     }
 
     /**
      * Constructor for already-in-mempool case. It wouldn't replace any
      * transactions.
      */
     static MempoolAcceptResult MempoolTx(int64_t vsize, Amount fees) {
         return MempoolAcceptResult(ResultType::MEMPOOL_ENTRY, vsize, fees);
     }
 
     // Private constructors. Use static methods MempoolAcceptResult::Success,
     // etc. to construct.
 private:
     /** Constructor for failure case */
     explicit MempoolAcceptResult(TxValidationState state)
         : m_result_type(ResultType::INVALID), m_state(state),
           m_base_fees(std::nullopt) {
         // Can be invalid or error
         Assume(!state.IsValid());
     }
 
     /** Generic constructor for success cases */
     explicit MempoolAcceptResult(ResultType result_type, int64_t vsize,
                                  Amount fees)
         : m_result_type(result_type), m_vsize{vsize}, m_base_fees(fees) {}
 };
 
 /**
  * Validation result for package mempool acceptance.
  */
 struct PackageMempoolAcceptResult {
     const PackageValidationState m_state;
     /**
      * Map from txid to finished MempoolAcceptResults. The client is
      * responsible for keeping track of the transaction objects themselves.
      * If a result is not present, it means validation was unfinished for that
      * transaction. If there was a package-wide error (see result in m_state),
      * m_tx_results will be empty.
      */
     std::map<const TxId, const MempoolAcceptResult> m_tx_results;
 
     explicit PackageMempoolAcceptResult(
         PackageValidationState state,
         std::map<const TxId, const MempoolAcceptResult> &&results)
         : m_state{state}, m_tx_results(std::move(results)) {}
 
     /**
      * Constructor to create a PackageMempoolAcceptResult from a
      * MempoolAcceptResult
      */
     explicit PackageMempoolAcceptResult(const TxId &txid,
                                         const MempoolAcceptResult &result)
         : m_tx_results{{txid, result}} {}
 };
 
 /**
  * Try to add a transaction to the mempool. This is an internal function and is
  * exposed only for testing. Client code should use
  * ChainstateManager::ProcessTransaction()
  *
  * @param[in]  active_chainstate  Reference to the active chainstate.
  * @param[in]  tx                 The transaction to submit for mempool
  *                                acceptance.
  * @param[in]  accept_time        The timestamp for adding the transaction to
  *                                the mempool.
  *                                It is also used to determine when the entry
  *                                expires.
  * @param[in]  bypass_limits      When true, don't enforce mempool fee and
  *                                capacity limits.
  * @param[in]  test_accept        When true, run validation checks but don't
  *                                submit to mempool.
  * @param[in]  heightOverride     Override the block height of the transaction.
  *                                Used only upon reorg.
  *
  * @returns a MempoolAcceptResult indicating whether the transaction was
  *     accepted/rejected with reason.
  */
 MempoolAcceptResult
 AcceptToMemoryPool(Chainstate &active_chainstate, const CTransactionRef &tx,
                    int64_t accept_time, bool bypass_limits,
                    bool test_accept = false, unsigned int heightOverride = 0)
     EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
 /**
  * Validate (and maybe submit) a package to the mempool.
  * See doc/policy/packages.md for full detailson package validation rules.
  *
  * @param[in]    test_accept     When true, run validation checks but don't
  *                               submit to mempool.
  * @returns a PackageMempoolAcceptResult which includes a MempoolAcceptResult
  *     for each transaction. If a transaction fails, validation will exit early
  *     and some results may be missing. It is also possible for the package to
  *     be partially submitted.
  */
 PackageMempoolAcceptResult
 ProcessNewPackage(Chainstate &active_chainstate, CTxMemPool &pool,
                   const Package &txns, bool test_accept)
     EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
 /**
  * Simple class for regulating resource usage during CheckInputScripts (and
  * CScriptCheck), atomic so as to be compatible with parallel validation.
  */
 class CheckInputsLimiter {
 protected:
     std::atomic<int64_t> remaining;
 
 public:
     explicit CheckInputsLimiter(int64_t limit) : remaining(limit) {}
 
     bool consume_and_check(int consumed) {
         auto newvalue = (remaining -= consumed);
         return newvalue >= 0;
     }
 
     bool check() { return remaining >= 0; }
 };
 
 class TxSigCheckLimiter : public CheckInputsLimiter {
 public:
     TxSigCheckLimiter() : CheckInputsLimiter(MAX_TX_SIGCHECKS) {}
 
     // Let's make this bad boy copiable.
     TxSigCheckLimiter(const TxSigCheckLimiter &rhs)
         : CheckInputsLimiter(rhs.remaining.load()) {}
 
     TxSigCheckLimiter &operator=(const TxSigCheckLimiter &rhs) {
         remaining = rhs.remaining.load();
         return *this;
     }
 
     static TxSigCheckLimiter getDisabled() {
         TxSigCheckLimiter txLimiter;
         // Historically, there has not been a transaction with more than 20k sig
         // checks on testnet or mainnet, so this effectively disable sigchecks.
         txLimiter.remaining = 20000;
         return txLimiter;
     }
 };
 
 class ConnectTrace;
 
 /**
  * Check whether all of this transaction's input scripts succeed.
  *
  * This involves ECDSA signature checks so can be computationally intensive.
  * This function should only be called after the cheap sanity checks in
  * CheckTxInputs passed.
  *
  * If pvChecks is not nullptr, script checks are pushed onto it instead of being
  * performed inline. Any script checks which are not necessary (eg due to script
  * execution cache hits) are, obviously, not pushed onto pvChecks/run.
  *
  * Upon success nSigChecksOut will be filled in with either:
  * - correct total for all inputs, or,
  * - 0, in the case when checks were pushed onto pvChecks (i.e., a cache miss
  * with pvChecks non-null), in which case the total can be found by executing
  * pvChecks and adding the results.
  *
  * Setting sigCacheStore/scriptCacheStore to false will remove elements from the
  * corresponding cache which are matched. This is useful for checking blocks
  * where we will likely never need the cache entry again.
  *
  * pLimitSigChecks can be passed to limit the sigchecks count either in parallel
  * or serial validation. With pvChecks null (serial validation), breaking the
  * pLimitSigChecks limit will abort evaluation early and return false. With
  * pvChecks not-null (parallel validation): the cached nSigChecks may itself
  * break the limit in which case false is returned, OR, each entry in the
  * returned pvChecks must be executed exactly once in order to probe the limit
  * accurately.
  */
 bool CheckInputScripts(const CTransaction &tx, TxValidationState &state,
                        const CCoinsViewCache &view, const uint32_t flags,
                        bool sigCacheStore, bool scriptCacheStore,
                        const PrecomputedTransactionData &txdata,
                        int &nSigChecksOut, TxSigCheckLimiter &txLimitSigChecks,
                        CheckInputsLimiter *pBlockLimitSigChecks,
                        std::vector<CScriptCheck> *pvChecks)
     EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
 /**
  * Handy shortcut to full fledged CheckInputScripts call.
  */
 static inline bool
 CheckInputScripts(const CTransaction &tx, TxValidationState &state,
                   const CCoinsViewCache &view, const uint32_t flags,
                   bool sigCacheStore, bool scriptCacheStore,
                   const PrecomputedTransactionData &txdata, int &nSigChecksOut)
     EXCLUSIVE_LOCKS_REQUIRED(cs_main) {
     TxSigCheckLimiter nSigChecksTxLimiter;
     return CheckInputScripts(tx, state, view, flags, sigCacheStore,
                              scriptCacheStore, txdata, nSigChecksOut,
                              nSigChecksTxLimiter, nullptr, nullptr);
 }
 
 /**
  * Mark all the coins corresponding to a given transaction inputs as spent.
  */
 void SpendCoins(CCoinsViewCache &view, const CTransaction &tx, CTxUndo &txundo,
                 int nHeight);
 
 /**
  * Apply the effects of this transaction on the UTXO set represented by view.
  */
 void UpdateCoins(CCoinsViewCache &view, const CTransaction &tx, CTxUndo &txundo,
                  int nHeight);
 
 /**
  * Check if transaction will be BIP68 final in the next block to be created on
  * top of tip.
  * @param[in]   tip             Chain tip to check tx sequence locks against.
  *     For example, the tip of the current active chain.
  * @param[in]   coins_view      Any CCoinsView that provides access to the
  *     relevant coins for checking sequence locks. For example, it can be a
  *     CCoinsViewCache that isn't connected to anything but contains all the
  *     relevant coins, or a CCoinsViewMemPool that is connected to the mempool
  *     and chainstate UTXO set. In the latter case, the caller is responsible
  *     for holding the appropriate locks to ensure that calls to GetCoin()
  *     return correct coins.
  * Simulates calling SequenceLocks() with data from the tip passed in.
  * Optionally stores in LockPoints the resulting height and time
  * calculated and the hash of the block needed for calculation or skips the
  * calculation and uses the LockPoints passed in for evaluation. The LockPoints
  * should not be considered valid if CheckSequenceLocksAtTip returns false.
  */
 bool CheckSequenceLocksAtTip(CBlockIndex *tip, const CCoinsView &coins_view,
                              const CTransaction &tx, LockPoints *lp = nullptr,
                              bool useExistingLockPoints = false);
 
 /**
  * Closure representing one script verification.
  * Note that this stores references to the spending transaction.
  *
  * Note that if pLimitSigChecks is passed, then failure does not imply that
  * scripts have failed.
  */
 class CScriptCheck {
 private:
     CTxOut m_tx_out;
     const CTransaction *ptxTo;
     unsigned int nIn;
     uint32_t nFlags;
     bool cacheStore;
     ScriptError error;
     ScriptExecutionMetrics metrics;
     PrecomputedTransactionData txdata;
     TxSigCheckLimiter *pTxLimitSigChecks;
     CheckInputsLimiter *pBlockLimitSigChecks;
 
 public:
     CScriptCheck()
         : ptxTo(nullptr), nIn(0), nFlags(0), cacheStore(false),
           error(ScriptError::UNKNOWN), txdata(), pTxLimitSigChecks(nullptr),
           pBlockLimitSigChecks(nullptr) {}
 
     CScriptCheck(const CTxOut &outIn, const CTransaction &txToIn,
                  unsigned int nInIn, uint32_t nFlagsIn, bool cacheIn,
                  const PrecomputedTransactionData &txdataIn,
                  TxSigCheckLimiter *pTxLimitSigChecksIn = nullptr,
                  CheckInputsLimiter *pBlockLimitSigChecksIn = nullptr)
         : m_tx_out(outIn), ptxTo(&txToIn), nIn(nInIn), nFlags(nFlagsIn),
           cacheStore(cacheIn), error(ScriptError::UNKNOWN), txdata(txdataIn),
           pTxLimitSigChecks(pTxLimitSigChecksIn),
           pBlockLimitSigChecks(pBlockLimitSigChecksIn) {}
 
     bool operator()();
 
     void swap(CScriptCheck &check) noexcept {
         std::swap(ptxTo, check.ptxTo);
         std::swap(m_tx_out, check.m_tx_out);
         std::swap(nIn, check.nIn);
         std::swap(nFlags, check.nFlags);
         std::swap(cacheStore, check.cacheStore);
         std::swap(error, check.error);
         std::swap(metrics, check.metrics);
         std::swap(txdata, check.txdata);
         std::swap(pTxLimitSigChecks, check.pTxLimitSigChecks);
         std::swap(pBlockLimitSigChecks, check.pBlockLimitSigChecks);
     }
 
     ScriptError GetScriptError() const { return error; }
 
     ScriptExecutionMetrics GetScriptExecutionMetrics() const { return metrics; }
 };
 
 /** Functions for validating blocks and updating the block tree */
 
 /**
  * Context-independent validity checks.
  *
  * Returns true if the provided block is valid (has valid header,
  * transactions are valid, block is a valid size, etc.)
  */
 bool CheckBlock(const CBlock &block, BlockValidationState &state,
                 const Consensus::Params &params,
                 BlockValidationOptions validationOptions);
 
 /**
  * This is a variant of ContextualCheckTransaction which computes the contextual
  * check for a transaction based on the chain tip.
  *
  * See consensus/consensus.h for flag definitions.
  */
 bool ContextualCheckTransactionForCurrentBlock(
     const CBlockIndex *active_chain_tip, const Consensus::Params &params,
     const CTransaction &tx, TxValidationState &state)
     EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
 /**
  * Check a block is completely valid from start to finish (only works on top of
  * our current best block)
  */
 bool TestBlockValidity(
     BlockValidationState &state, const CChainParams &params,
     Chainstate &chainstate, const CBlock &block, CBlockIndex *pindexPrev,
     const std::function<NodeClock::time_point()> &adjusted_time_callback,
     BlockValidationOptions validationOptions) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
 /**
  * Check with the proof of work on each blockheader matches the value in nBits
  */
 bool HasValidProofOfWork(const std::vector<CBlockHeader> &headers,
                          const Consensus::Params &consensusParams);
 
 /** Return the sum of the work on a given set of headers */
 arith_uint256 CalculateHeadersWork(const std::vector<CBlockHeader> &headers);
 
 enum class VerifyDBResult {
     SUCCESS,
     CORRUPTED_BLOCK_DB,
     INTERRUPTED,
     SKIPPED_L3_CHECKS,
     SKIPPED_MISSING_BLOCKS,
 };
 
 /**
  * RAII wrapper for VerifyDB: Verify consistency of the block and coin
  * databases.
  */
 class CVerifyDB {
 public:
     CVerifyDB();
 
     ~CVerifyDB();
 
     [[nodiscard]] VerifyDBResult VerifyDB(Chainstate &chainstate,
                                           CCoinsView &coinsview,
                                           int nCheckLevel, int nCheckDepth)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 };
 
 /** @see Chainstate::FlushStateToDisk */
 enum class FlushStateMode { NONE, IF_NEEDED, PERIODIC, ALWAYS };
 
 /**
  * A convenience class for constructing the CCoinsView* hierarchy used
  * to facilitate access to the UTXO set.
  *
  * This class consists of an arrangement of layered CCoinsView objects,
  * preferring to store and retrieve coins in memory via `m_cacheview` but
  * ultimately falling back on cache misses to the canonical store of UTXOs on
  * disk, `m_dbview`.
  */
 class CoinsViews {
 public:
     //! The lowest level of the CoinsViews cache hierarchy sits in a leveldb
     //! database on disk. All unspent coins reside in this store.
     CCoinsViewDB m_dbview GUARDED_BY(cs_main);
 
     //! This view wraps access to the leveldb instance and handles read errors
     //! gracefully.
     CCoinsViewErrorCatcher m_catcherview GUARDED_BY(cs_main);
 
     //! This is the top layer of the cache hierarchy - it keeps as many coins in
     //! memory as can fit per the dbcache setting.
     std::unique_ptr<CCoinsViewCache> m_cacheview GUARDED_BY(cs_main);
 
     //! This constructor initializes CCoinsViewDB and CCoinsViewErrorCatcher
     //! instances, but it *does not* create a CCoinsViewCache instance by
     //! default. This is done separately because the presence of the cache has
     //! implications on whether or not we're allowed to flush the cache's state
     //! to disk, which should not be done until the health of the database is
     //! verified.
     //!
     //! All arguments forwarded onto CCoinsViewDB.
     CoinsViews(std::string ldb_name, size_t cache_size_bytes, bool in_memory,
                bool should_wipe);
 
     //! Initialize the CCoinsViewCache member.
     void InitCache() EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 };
 
 enum class CoinsCacheSizeState {
     //! The coins cache is in immediate need of a flush.
     CRITICAL = 2,
     //! The cache is at >= 90% capacity.
     LARGE = 1,
     OK = 0
 };
 
 /**
  * Chainstate stores and provides an API to update our local knowledge of the
  * current best chain.
  *
  * Eventually, the API here is targeted at being exposed externally as a
  * consumable libconsensus library, so any functions added must only call
  * other class member functions, pure functions in other parts of the consensus
  * library, callbacks via the validation interface, or read/write-to-disk
  * functions (eventually this will also be via callbacks).
  *
  * Anything that is contingent on the current tip of the chain is stored here,
  * whereas block information and metadata independent of the current tip is
  * kept in `BlockManager`.
  */
 class Chainstate {
 protected:
     /**
      * The ChainState Mutex.
      * A lock that must be held when modifying this ChainState.
      */
     Mutex m_chainstate_mutex;
 
     /**
      * Every received block is assigned a unique and increasing identifier, so
      * we know which one to give priority in case of a fork.
      * Blocks loaded from disk are assigned id 0, so start the counter at 1.
      */
     std::atomic<int32_t> nBlockSequenceId{1};
     /** Decreasing counter (used by subsequent preciousblock calls). */
     int32_t nBlockReverseSequenceId = -1;
     /** chainwork for the last block that preciousblock has been applied to. */
     arith_uint256 nLastPreciousChainwork = 0;
 
     /**
      * Whether this chainstate is undergoing initial block download.
      *
      * Mutable because we need to be able to mark IsInitialBlockDownload()
      * const, which latches this for caching purposes.
      */
     mutable std::atomic<bool> m_cached_finished_ibd{false};
 
     //! Optional mempool that is kept in sync with the chain.
     //! Only the active chainstate has a mempool.
     CTxMemPool *m_mempool;
 
     //! Manages the UTXO set, which is a reflection of the contents of
     //! `m_chain`.
     std::unique_ptr<CoinsViews> m_coins_views;
 
     //! This toggle exists for use when doing background validation for UTXO
     //! snapshots.
     //!
     //! In the expected case, it is set once the background validation chain
     //! reaches the same height as the base of the snapshot and its UTXO set is
     //! found to hash to the expected assumeutxo value. It signals that we
     //! should no longer connect blocks to the background chainstate. When set
     //! on the background validation chainstate, it signifies that we have fully
     //! validated the snapshot chainstate.
     //!
     //! In the unlikely case that the snapshot chainstate is found to be
     //! invalid, this is set to true on the snapshot chainstate.
     bool m_disabled GUARDED_BY(::cs_main){false};
 
     mutable Mutex cs_avalancheFinalizedBlockIndex;
 
     /**
      * The best block via avalanche voting.
      * This block cannot be reorged in any way except by explicit user action.
      */
     const CBlockIndex *m_avalancheFinalizedBlockIndex
         GUARDED_BY(cs_avalancheFinalizedBlockIndex) = nullptr;
 
     /**
      * Filter to prevent parking a block due to block policies more than once.
      * After first application of block policies, Avalanche voting will
      * determine the final acceptance state. Rare false positives will be
      * reconciled by the network and should not have any negative impact.
      */
     CRollingBloomFilter m_filterParkingPoliciesApplied =
         CRollingBloomFilter{1000, 0.000001};
 
     CBlockIndex const *m_best_fork_tip = nullptr;
     CBlockIndex const *m_best_fork_base = nullptr;
 
 public:
     //! Reference to a BlockManager instance which itself is shared across all
     //! Chainstate instances.
     node::BlockManager &m_blockman;
 
     //! The chainstate manager that owns this chainstate. The reference is
     //! necessary so that this instance can check whether it is the active
     //! chainstate within deeply nested method calls.
     ChainstateManager &m_chainman;
 
     explicit Chainstate(
         CTxMemPool *mempool, node::BlockManager &blockman,
         ChainstateManager &chainman,
         std::optional<BlockHash> from_snapshot_blockhash = std::nullopt);
 
     /**
      * Initialize the CoinsViews UTXO set database management data structures.
      * The in-memory cache is initialized separately.
      *
      * All parameters forwarded to CoinsViews.
      */
     void InitCoinsDB(size_t cache_size_bytes, bool in_memory, bool should_wipe,
                      std::string leveldb_name = "chainstate");
 
     //! Initialize the in-memory coins cache (to be done after the health of the
     //! on-disk database is verified).
     void InitCoinsCache(size_t cache_size_bytes)
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     //! @returns whether or not the CoinsViews object has been fully initialized
     //! and we can
     //!          safely flush this object to disk.
     bool CanFlushToDisk() const EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {
         AssertLockHeld(::cs_main);
         return m_coins_views && m_coins_views->m_cacheview;
     }
 
     //! The current chain of blockheaders we consult and build on.
     //! @see CChain, CBlockIndex.
     CChain m_chain;
 
     /**
      * The blockhash which is the base of the snapshot this chainstate was
      * created from.
      *
      * std::nullopt if this chainstate was not created from a snapshot.
      */
     const std::optional<BlockHash> m_from_snapshot_blockhash{};
 
     //! Return true if this chainstate relies on blocks that are assumed-valid.
     //! In practice this means it was created based on a UTXO snapshot.
     bool reliesOnAssumedValid() {
         return m_from_snapshot_blockhash.has_value();
     }
 
     /**
      * The set of all CBlockIndex entries with either BLOCK_VALID_TRANSACTIONS
      * (for itself and all ancestors) *or* BLOCK_ASSUMED_VALID (if using
      * background chainstates) and as good as our current tip or better.
      * Entries may be failed, though, and pruning nodes may be missing the data
      * for the block.
      */
     std::set<CBlockIndex *, CBlockIndexWorkComparator> setBlockIndexCandidates;
 
     //! @returns A reference to the in-memory cache of the UTXO set.
     CCoinsViewCache &CoinsTip() EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {
         AssertLockHeld(::cs_main);
         Assert(m_coins_views);
         return *Assert(m_coins_views->m_cacheview);
     }
 
     //! @returns A reference to the on-disk UTXO set database.
     CCoinsViewDB &CoinsDB() EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {
         AssertLockHeld(::cs_main);
         return Assert(m_coins_views)->m_dbview;
     }
 
     //! @returns A pointer to the mempool.
     CTxMemPool *GetMempool() { return m_mempool; }
 
     //! @returns A reference to a wrapped view of the in-memory UTXO set that
     //!     handles disk read errors gracefully.
     CCoinsViewErrorCatcher &CoinsErrorCatcher()
         EXCLUSIVE_LOCKS_REQUIRED(cs_main) {
         AssertLockHeld(::cs_main);
         return Assert(m_coins_views)->m_catcherview;
     }
 
     //! Destructs all objects related to accessing the UTXO set.
     void ResetCoinsViews() { m_coins_views.reset(); }
 
     //! Does this chainstate have a UTXO set attached?
     bool HasCoinsViews() const { return (bool)m_coins_views; }
 
     //! The cache size of the on-disk coins view.
     size_t m_coinsdb_cache_size_bytes{0};
 
     //! The cache size of the in-memory coins view.
     size_t m_coinstip_cache_size_bytes{0};
 
     //! Resize the CoinsViews caches dynamically and flush state to disk.
     //! @returns true unless an error occurred during the flush.
     bool ResizeCoinsCaches(size_t coinstip_size, size_t coinsdb_size)
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     /**
      * Import blocks from an external file
      *
      * During reindexing, this function is called for each block file
      * (datadir/blocks/blk?????.dat). It reads all blocks contained in the given
      * file and attempts to process them (add them to the block index). The
      * blocks may be out of order within each file and across files. Often this
      * function reads a block but finds that its parent hasn't been read yet, so
      * the block can't be processed yet. The function will add an entry to the
      * blocks_with_unknown_parent map (which is passed as an argument), so that
      * when the block's parent is later read and processed, this function can
      * re-read the child block from disk and process it.
      *
      * Because a block's parent may be in a later file, not just later in the
      * same file, the blocks_with_unknown_parent map must be passed in and out
      * with each call. It's a multimap, rather than just a map, because multiple
      * blocks may have the same parent (when chain splits or stale blocks
      * exist). It maps from parent-hash to child-disk-position.
      *
      * This function can also be used to read blocks from user-specified block
      * files using the -loadblock= option. There's no unknown-parent tracking,
      * so the last two arguments are omitted.
      *
      *
      * @param[in]     fileIn  FILE handle to file containing blocks to read
      * @param[in]     dbp     (optional) Disk block position (only for reindex)
      * @param[in,out] blocks_with_unknown_parent
      *                        (optional) Map of disk positions for blocks with
      *                        unknown parent, key is parent block hash
      *                        (only used for reindex)
      */
     void LoadExternalBlockFile(FILE *fileIn, FlatFilePos *dbp = nullptr,
                                std::multimap<BlockHash, FlatFilePos>
                                    *blocks_with_unknown_parent = nullptr)
         EXCLUSIVE_LOCKS_REQUIRED(!m_chainstate_mutex,
                                  !cs_avalancheFinalizedBlockIndex);
 
     /**
      * Update the on-disk chain state.
      * The caches and indexes are flushed depending on the mode we're called
      * with if they're too large, if it's been a while since the last write, or
      * always and in all cases if we're in prune mode and are deleting files.
      *
      * If FlushStateMode::NONE is used, then FlushStateToDisk(...) won't do
      * anything besides checking if we need to prune.
      *
      * @returns true unless a system error occurred
      */
     bool FlushStateToDisk(BlockValidationState &state, FlushStateMode mode,
                           int nManualPruneHeight = 0);
 
     //! Unconditionally flush all changes to disk.
     void ForceFlushStateToDisk();
 
     //! Prune blockfiles from the disk if necessary and then flush chainstate
     //! changes if we pruned.
     void PruneAndFlush();
 
     /**
      * Find the best known block, and make it the tip of the block chain. The
      * result is either failure or an activated best chain. pblock is either
      * nullptr or a pointer to a block that is already loaded (to avoid loading
      * it again from disk).
      *
      * ActivateBestChain is split into steps (see ActivateBestChainStep) so that
      * we avoid holding cs_main for an extended period of time; the length of
      * this call may be quite long during reindexing or a substantial reorg.
      *
      * May not be called with cs_main held. May not be called in a
      * validationinterface callback.
      *
      * Note that if this is called while a snapshot chainstate is active, and if
      * it is called on a background chainstate whose tip has reached the base
      * block of the snapshot, its execution will take *MINUTES* while it hashes
      * the background UTXO set to verify the assumeutxo value the snapshot was
      * activated with. `cs_main` will be held during this time.
      *
      * @param[in] skip_checkblockindex (optional)
      *     If true, skip calling CheckBlockIndex even if -checkblockindex is
      *     true. If false (default behavior), respect the -checkblockindex arg.
      *     This is used in tests when we need to skip the checks only
      *     temporarily, and resume normal behavior later.
      * @returns true unless a system error occurred
      */
     bool ActivateBestChain(BlockValidationState &state,
                            std::shared_ptr<const CBlock> pblock = nullptr,
                            bool skip_checkblockindex = false)
         EXCLUSIVE_LOCKS_REQUIRED(!m_chainstate_mutex,
                                  !cs_avalancheFinalizedBlockIndex)
             LOCKS_EXCLUDED(cs_main);
 
     bool AcceptBlock(const std::shared_ptr<const CBlock> &pblock,
                      BlockValidationState &state, bool fRequested,
                      const FlatFilePos *dbp, bool *fNewBlock,
                      bool min_pow_checked) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     // Block (dis)connection on a given view:
     DisconnectResult DisconnectBlock(const CBlock &block,
                                      const CBlockIndex *pindex,
                                      CCoinsViewCache &view)
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
     bool ConnectBlock(const CBlock &block, BlockValidationState &state,
                       CBlockIndex *pindex, CCoinsViewCache &view,
                       BlockValidationOptions options,
                       Amount *blockFees = nullptr, bool fJustCheck = false)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     // Apply the effects of a block disconnection on the UTXO set.
     bool DisconnectTip(BlockValidationState &state,
                        DisconnectedBlockTransactions *disconnectpool)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_mempool->cs);
 
     // Manual block validity manipulation:
     /**
      * Mark a block as precious and reorganize.
      *
      * May not be called in a validationinterface callback.
      */
     bool PreciousBlock(BlockValidationState &state, CBlockIndex *pindex)
         EXCLUSIVE_LOCKS_REQUIRED(!m_chainstate_mutex,
                                  !cs_avalancheFinalizedBlockIndex)
             LOCKS_EXCLUDED(cs_main);
     /** Mark a block as invalid. */
     bool InvalidateBlock(BlockValidationState &state, CBlockIndex *pindex)
         LOCKS_EXCLUDED(cs_main)
             EXCLUSIVE_LOCKS_REQUIRED(!m_chainstate_mutex,
                                      !cs_avalancheFinalizedBlockIndex);
     /** Park a block. */
     bool ParkBlock(BlockValidationState &state, CBlockIndex *pindex)
         LOCKS_EXCLUDED(cs_main)
             EXCLUSIVE_LOCKS_REQUIRED(!m_chainstate_mutex,
                                      !cs_avalancheFinalizedBlockIndex);
 
     /**
      * Mark a block as finalized by avalanche.
      */
     bool AvalancheFinalizeBlock(CBlockIndex *pindex)
         EXCLUSIVE_LOCKS_REQUIRED(!cs_avalancheFinalizedBlockIndex);
 
     /**
      * Clear avalanche finalization.
      */
     void ClearAvalancheFinalizedBlock()
         EXCLUSIVE_LOCKS_REQUIRED(!cs_avalancheFinalizedBlockIndex);
 
     /**
      * Checks if a block is finalized by avalanche voting.
      */
     bool IsBlockAvalancheFinalized(const CBlockIndex *pindex) const
         EXCLUSIVE_LOCKS_REQUIRED(!cs_avalancheFinalizedBlockIndex);
 
     /** Remove invalidity status from a block and its descendants. */
     void ResetBlockFailureFlags(CBlockIndex *pindex)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
     template <typename F>
     bool UpdateFlagsForBlock(CBlockIndex *pindexBase, CBlockIndex *pindex, F f)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
     template <typename F, typename C, typename AC>
     void UpdateFlags(CBlockIndex *pindex, CBlockIndex *&pindexReset, F f,
                      C fChild, AC fAncestorWasChanged)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     /** Remove parked status from a block and its descendants. */
     void UnparkBlockAndChildren(CBlockIndex *pindex)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     /** Remove parked status from a block. */
     void UnparkBlock(CBlockIndex *pindex) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     /** Replay blocks that aren't fully applied to the database. */
     bool ReplayBlocks();
 
     /**
      * Ensures we have a genesis block in the block tree, possibly writing one
      * to disk.
      */
     bool LoadGenesisBlock();
 
     void PruneBlockIndexCandidates();
 
     void UnloadBlockIndex() EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     /**
      * Check whether we are doing an initial block download (synchronizing from
      * disk or network)
      */
     bool IsInitialBlockDownload() const;
 
     /** Find the last common block of this chain and a locator. */
     const CBlockIndex *FindForkInGlobalIndex(const CBlockLocator &locator) const
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     /**
      * Make various assertions about the state of the block index.
      *
      * By default this only executes fully when using the Regtest chain; see:
      * m_options.check_block_index.
      */
     void CheckBlockIndex();
 
     /** Load the persisted mempool from disk */
     void
     LoadMempool(const fs::path &load_path,
                 fsbridge::FopenFn mockable_fopen_function = fsbridge::fopen);
 
     /** Update the chain tip based on database information, i.e. CoinsTip()'s
      * best block. */
     bool LoadChainTip() EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     //! Dictates whether we need to flush the cache to disk or not.
     //!
     //! @return the state of the size of the coins cache.
     CoinsCacheSizeState GetCoinsCacheSizeState()
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     CoinsCacheSizeState
     GetCoinsCacheSizeState(size_t max_coins_cache_size_bytes,
                            size_t max_mempool_size_bytes)
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     std::string ToString() EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     //! Indirection necessary to make lock annotations work with an optional
     //! mempool.
     RecursiveMutex *MempoolMutex() const LOCK_RETURNED(m_mempool->cs) {
         return m_mempool ? &m_mempool->cs : nullptr;
     }
 
 private:
     bool ActivateBestChainStep(BlockValidationState &state,
                                CBlockIndex *pindexMostWork,
                                const std::shared_ptr<const CBlock> &pblock,
                                bool &fInvalidFound, ConnectTrace &connectTrace)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_mempool->cs,
                                  !cs_avalancheFinalizedBlockIndex);
     bool ConnectTip(BlockValidationState &state,
                     BlockPolicyValidationState &blockPolicyState,
                     CBlockIndex *pindexNew,
                     const std::shared_ptr<const CBlock> &pblock,
                     ConnectTrace &connectTrace,
                     DisconnectedBlockTransactions &disconnectpool)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_mempool->cs,
                                  !cs_avalancheFinalizedBlockIndex);
     void InvalidBlockFound(CBlockIndex *pindex,
                            const BlockValidationState &state)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main, !cs_avalancheFinalizedBlockIndex);
     CBlockIndex *
     FindMostWorkChain(std::vector<const CBlockIndex *> &blocksToReconcile)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main, !cs_avalancheFinalizedBlockIndex);
     void ReceivedBlockTransactions(const CBlock &block, CBlockIndex *pindexNew,
                                    const FlatFilePos &pos)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     bool RollforwardBlock(const CBlockIndex *pindex, CCoinsViewCache &inputs)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     void UnparkBlockImpl(CBlockIndex *pindex, bool fClearChildren)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     bool UnwindBlock(BlockValidationState &state, CBlockIndex *pindex,
                      bool invalidate)
         EXCLUSIVE_LOCKS_REQUIRED(m_chainstate_mutex,
                                  !cs_avalancheFinalizedBlockIndex);
 
     void CheckForkWarningConditions() EXCLUSIVE_LOCKS_REQUIRED(cs_main);
     void CheckForkWarningConditionsOnNewFork(CBlockIndex *pindexNewForkTip)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
     void InvalidChainFound(CBlockIndex *pindexNew)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main, !cs_avalancheFinalizedBlockIndex);
 
     const CBlockIndex *FindBlockToFinalize(CBlockIndex *pindexNew)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     /**
      * Check warning conditions and do some notifications on new chain tip set.
      */
     void UpdateTip(const CBlockIndex *pindexNew)
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     std::chrono::microseconds m_last_write{0};
     std::chrono::microseconds m_last_flush{0};
 
     /**
      * In case of an invalid snapshot, rename the coins leveldb directory so
      * that it can be examined for issue diagnosis.
      */
     void InvalidateCoinsDBOnDisk() EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     friend ChainstateManager;
 };
 
 enum class SnapshotCompletionResult {
     SUCCESS,
     SKIPPED,
 
     // Expected assumeutxo configuration data is not found for the height of the
     // base block.
     MISSING_CHAINPARAMS,
 
     // Failed to generate UTXO statistics (to check UTXO set hash) for the
     // background chainstate.
     STATS_FAILED,
 
     // The UTXO set hash of the background validation chainstate does not match
     // the one expected by assumeutxo chainparams.
     HASH_MISMATCH,
 
     // The blockhash of the current tip of the background validation chainstate
     // does not match the one expected by the snapshot chainstate.
     BASE_BLOCKHASH_MISMATCH,
 };
 
 /**
  * Provides an interface for creating and interacting with one or two
  * chainstates: an IBD chainstate generated by downloading blocks, and
  * an optional snapshot chainstate loaded from a UTXO snapshot. Managed
  * chainstates can be maintained at different heights simultaneously.
  *
  * This class provides abstractions that allow the retrieval of the current
  * most-work chainstate ("Active") as well as chainstates which may be in
  * background use to validate UTXO snapshots.
  *
  * Definitions:
  *
  * *IBD chainstate*: a chainstate whose current state has been "fully"
  *   validated by the initial block download process.
  *
  * *Snapshot chainstate*: a chainstate populated by loading in an
  *    assumeutxo UTXO snapshot.
  *
  * *Active chainstate*: the chainstate containing the current most-work
  *    chain. Consulted by most parts of the system (net_processing,
  *    wallet) as a reflection of the current chain and UTXO set.
  *    This may either be an IBD chainstate or a snapshot chainstate.
  *
  * *Background IBD chainstate*: an IBD chainstate for which the
  *    IBD process is happening in the background while use of the
  *    active (snapshot) chainstate allows the rest of the system to function.
  */
 class ChainstateManager {
 private:
     //! The chainstate used under normal operation (i.e. "regular" IBD) or, if
     //! a snapshot is in use, for background validation.
     //!
     //! Its contents (including on-disk data) will be deleted *upon shutdown*
     //! after background validation of the snapshot has completed. We do not
     //! free the chainstate contents immediately after it finishes validation
     //! to cautiously avoid a case where some other part of the system is still
     //! using this pointer (e.g. net_processing).
     //!
     //! Once this pointer is set to a corresponding chainstate, it will not
     //! be reset until init.cpp:Shutdown().
     //!
     //! This is especially important when, e.g., calling ActivateBestChain()
     //! on all chainstates because we are not able to hold ::cs_main going into
     //! that call.
     std::unique_ptr<Chainstate> m_ibd_chainstate GUARDED_BY(::cs_main);
 
     //! A chainstate initialized on the basis of a UTXO snapshot. If this is
     //! non-null, it is always our active chainstate.
     //!
     //! Once this pointer is set to a corresponding chainstate, it will not
     //! be reset until init.cpp:Shutdown().
     //!
     //! This is especially important when, e.g., calling ActivateBestChain()
     //! on all chainstates because we are not able to hold ::cs_main going into
     //! that call.
     std::unique_ptr<Chainstate> m_snapshot_chainstate GUARDED_BY(::cs_main);
 
     //! Points to either the ibd or snapshot chainstate; indicates our
     //! most-work chain.
     //!
     //! Once this pointer is set to a corresponding chainstate, it will not
     //! be reset until init.cpp:Shutdown().
     //!
     //! This is especially important when, e.g., calling ActivateBestChain()
     //! on all chainstates because we are not able to hold ::cs_main going into
     //! that call.
     Chainstate *m_active_chainstate GUARDED_BY(::cs_main){nullptr};
 
     CBlockIndex *m_best_invalid GUARDED_BY(::cs_main){nullptr};
     CBlockIndex *m_best_parked GUARDED_BY(::cs_main){nullptr};
 
     //! Internal helper for ActivateSnapshot().
     [[nodiscard]] bool
     PopulateAndValidateSnapshot(Chainstate &snapshot_chainstate,
                                 AutoFile &coins_file,
                                 const node::SnapshotMetadata &metadata);
     /**
      * If a block header hasn't already been seen, call CheckBlockHeader on it,
      * ensure that it doesn't descend from an invalid block, and then add it to
      * m_block_index.
      * Caller must set min_pow_checked=true in order to add a new header to the
      * block index (permanent memory storage), indicating that the header is
      * known to be part of a sufficiently high-work chain (anti-dos check).
      */
-    bool AcceptBlockHeader(const CBlockHeader &block,
-                           BlockValidationState &state, CBlockIndex **ppindex,
-                           bool min_pow_checked)
+    bool AcceptBlockHeader(
+        const CBlockHeader &block, BlockValidationState &state,
+        CBlockIndex **ppindex, bool min_pow_checked,
+        const std::optional<CCheckpointData> &test_checkpoints = std::nullopt)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
     friend Chainstate;
 
     //! Returns nullptr if no snapshot has been loaded.
     const CBlockIndex *GetSnapshotBaseBlock() const
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     //! Return the height of the base block of the snapshot in use, if one
     //! exists, else nullopt.
     std::optional<int> GetSnapshotBaseHeight() const
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     //! Return true if a chainstate is considered usable.
     //!
     //! This is false when a background validation chainstate has completed its
     //! validation of an assumed-valid chainstate, or when a snapshot
     //! chainstate has been found to be invalid.
     bool IsUsable(const Chainstate *const pchainstate) const
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {
         return pchainstate && !pchainstate->m_disabled;
     }
 
     /** Most recent headers presync progress update, for rate-limiting. */
     SteadyMilliseconds m_last_presync_update GUARDED_BY(::cs_main){};
 
 public:
     using Options = kernel::ChainstateManagerOpts;
 
     explicit ChainstateManager(Options options);
 
     const Config &GetConfig() const { return m_options.config; }
 
     const CChainParams &GetParams() const {
         return m_options.config.GetChainParams();
     }
     const Consensus::Params &GetConsensus() const {
         return m_options.config.GetChainParams().GetConsensus();
     }
     bool ShouldCheckBlockIndex() const {
         return *Assert(m_options.check_block_index);
     }
     const arith_uint256 &MinimumChainWork() const {
         return *Assert(m_options.minimum_chain_work);
     }
     const BlockHash &AssumedValidBlock() const {
         return *Assert(m_options.assumed_valid_block);
     }
 
     /**
      * Alias for ::cs_main.
      * Should be used in new code to make it easier to make ::cs_main a member
      * of this class.
      * Generally, methods of this class should be annotated to require this
      * mutex. This will make calling code more verbose, but also help to:
      * - Clarify that the method will acquire a mutex that heavily affects
      *   overall performance.
      * - Force call sites to think how long they need to acquire the mutex to
      *   get consistent results.
      */
     RecursiveMutex &GetMutex() const LOCK_RETURNED(::cs_main) {
         return ::cs_main;
     }
 
     const Options m_options;
     std::thread m_load_block;
     //! A single BlockManager instance is shared across each constructed
     //! chainstate to avoid duplicating block metadata.
     node::BlockManager m_blockman;
 
     /**
      * In order to efficiently track invalidity of headers, we keep the set of
      * blocks which we tried to connect and found to be invalid here (ie which
      * were set to BLOCK_FAILED_VALID since the last restart). We can then
      * walk this set and check if a new header is a descendant of something in
      * this set, preventing us from having to walk m_block_index when we try
      * to connect a bad block and fail.
      *
      * While this is more complicated than marking everything which descends
      * from an invalid block as invalid at the time we discover it to be
      * invalid, doing so would require walking all of m_block_index to find all
      * descendants. Since this case should be very rare, keeping track of all
      * BLOCK_FAILED_VALID blocks in a set should be just fine and work just as
      * well.
      *
      * Because we already walk m_block_index in height-order at startup, we go
      * ahead and mark descendants of invalid blocks as FAILED_CHILD at that
      * time, instead of putting things in this set.
      */
     std::set<CBlockIndex *> m_failed_blocks;
 
     /**
      * Best header we've seen so far (used for getheaders queries' starting
      * points).
      */
     CBlockIndex *m_best_header GUARDED_BY(::cs_main){nullptr};
 
     //! The total number of bytes available for us to use across all in-memory
     //! coins caches. This will be split somehow across chainstates.
     int64_t m_total_coinstip_cache{0};
     //
     //! The total number of bytes available for us to use across all leveldb
     //! coins databases. This will be split somehow across chainstates.
     int64_t m_total_coinsdb_cache{0};
 
     //! Instantiate a new chainstate.
     //!
     //! @param[in] mempool              The mempool to pass to the chainstate
     //                                  constructor
     Chainstate &InitializeChainstate(CTxMemPool *mempool)
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     //! Get all chainstates currently being used.
     std::vector<Chainstate *> GetAll();
 
     //! Construct and activate a Chainstate on the basis of UTXO snapshot data.
     //!
     //! Steps:
     //!
     //! - Initialize an unused Chainstate.
     //! - Load its `CoinsViews` contents from `coins_file`.
     //! - Verify that the hash of the resulting coinsdb matches the expected
     //!   hash per assumeutxo chain parameters.
     //! - Wait for our headers chain to include the base block of the snapshot.
     //! - "Fast forward" the tip of the new chainstate to the base of the
     //!   snapshot, faking nTx* block index data along the way.
     //! - Move the new chainstate to `m_snapshot_chainstate` and make it our
     //!   ActiveChainstate().
     [[nodiscard]] bool ActivateSnapshot(AutoFile &coins_file,
                                         const node::SnapshotMetadata &metadata,
                                         bool in_memory);
 
     //! Once the background validation chainstate has reached the height which
     //! is the base of the UTXO snapshot in use, compare its coins to ensure
     //! they match those expected by the snapshot.
     //!
     //! If the coins match (expected), then mark the validation chainstate for
     //! deletion and continue using the snapshot chainstate as active.
     //! Otherwise, revert to using the ibd chainstate and shutdown.
     SnapshotCompletionResult MaybeCompleteSnapshotValidation(
         std::function<void(bilingual_str)> shutdown_fnc =
             [](bilingual_str msg) { AbortNode(msg.original, msg); })
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     //! The most-work chain.
     Chainstate &ActiveChainstate() const;
     CChain &ActiveChain() const EXCLUSIVE_LOCKS_REQUIRED(GetMutex()) {
         return ActiveChainstate().m_chain;
     }
     int ActiveHeight() const EXCLUSIVE_LOCKS_REQUIRED(GetMutex()) {
         return ActiveChain().Height();
     }
     CBlockIndex *ActiveTip() const EXCLUSIVE_LOCKS_REQUIRED(GetMutex()) {
         return ActiveChain().Tip();
     }
 
     node::BlockMap &BlockIndex() EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {
         AssertLockHeld(::cs_main);
         return m_blockman.m_block_index;
     }
 
     //! @returns true if a snapshot-based chainstate is in use. Also implies
     //!          that a background validation chainstate is also in use.
     bool IsSnapshotActive() const;
 
     std::optional<BlockHash> SnapshotBlockhash() const;
 
     //! Is there a snapshot in use and has it been fully validated?
     bool IsSnapshotValidated() const EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {
         return m_snapshot_chainstate && m_ibd_chainstate &&
                m_ibd_chainstate->m_disabled;
     }
 
     /**
      * Process an incoming block. This only returns after the best known valid
      * block is made active. Note that it does not, however, guarantee that the
      * specific block passed to it has been checked for validity!
      *
      * If you want to *possibly* get feedback on whether block is valid, you
      * must install a CValidationInterface (see validationinterface.h) - this
      * will have its BlockChecked method called whenever *any* block completes
      * validation.
      *
      * Note that we guarantee that either the proof-of-work is valid on block,
      * or (and possibly also) BlockChecked will have been called.
      *
      * May not be called in a validationinterface callback.
      *
      * @param[in]   block  The block we want to process.
      * @param[in]   force_processing Process this block even if unrequested;
      *                               used for non-network block sources.
      * @param[in]   min_pow_checked  True if proof-of-work anti-DoS checks have
      *                               been done by caller for headers chain
      *                               (note: only affects headers acceptance; if
      *                               block header is already present in block
      *                               index then this parameter has no effect)
      * @param[out]  new_block A boolean which is set to indicate if the block
      * was first received via this call.
      * @returns     If the block was processed, independently of block validity
      */
     bool ProcessNewBlock(const std::shared_ptr<const CBlock> &block,
                          bool force_processing, bool min_pow_checked,
                          bool *new_block) LOCKS_EXCLUDED(cs_main);
 
     /**
      * Process incoming block headers.
      *
      * May not be called in a validationinterface callback.
      *
      * @param[in]  block         The block headers themselves.
      * @param[in]  min_pow_checked  True if proof-of-work anti-DoS checks have
      *                              been done by caller for headers chain
      * @param[out] state         This may be set to an Error state if any error
      *                           occurred processing them.
      * @param[out] ppindex       If set, the pointer will be set to point to the
      *                           last new block index object for the given
      * headers.
      * @return True if block headers were accepted as valid.
      */
-    bool ProcessNewBlockHeaders(const std::vector<CBlockHeader> &block,
-                                bool min_pow_checked,
-                                BlockValidationState &state,
-                                const CBlockIndex **ppindex = nullptr)
+    bool ProcessNewBlockHeaders(
+        const std::vector<CBlockHeader> &block, bool min_pow_checked,
+        BlockValidationState &state, const CBlockIndex **ppindex = nullptr,
+        const std::optional<CCheckpointData> &test_checkpoints = std::nullopt)
         LOCKS_EXCLUDED(cs_main);
 
     /**
      * Try to add a transaction to the memory pool.
      *
      * @param[in]  tx              The transaction to submit for mempool
      *                             acceptance.
      * @param[in]  test_accept     When true, run validation checks but don't
      *                             submit to mempool.
      */
     [[nodiscard]] MempoolAcceptResult
     ProcessTransaction(const CTransactionRef &tx, bool test_accept = false)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     //! Load the block tree and coins database from disk, initializing state if
     //! we're running with -reindex
     bool LoadBlockIndex() EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     //! Check to see if caches are out of balance and if so, call
     //! ResizeCoinsCaches() as needed.
     void MaybeRebalanceCaches() EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     /**
      * This is used by net_processing to report pre-synchronization progress of
      * headers, as headers are not yet fed to validation during that time, but
      * validation is (for now) responsible for logging and signalling through
      * NotifyHeaderTip, so it needs this information.
      */
     void ReportHeadersPresync(const arith_uint256 &work, int64_t height,
                               int64_t timestamp);
 
     //! When starting up, search the datadir for a chainstate based on a UTXO
     //! snapshot that is in the process of being validated.
     bool DetectSnapshotChainstate(CTxMemPool *mempool)
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     void ResetChainstates() EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     //! Switch the active chainstate to one based on a UTXO snapshot that was
     //! loaded previously.
     Chainstate &ActivateExistingSnapshot(CTxMemPool *mempool,
                                          BlockHash base_blockhash)
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     //! If we have validated a snapshot chain during this runtime, copy its
     //! chainstate directory over to the main `chainstate` location, completing
     //! validation of the snapshot.
     //!
     //! If the cleanup succeeds, the caller will need to ensure chainstates are
     //! reinitialized, since ResetChainstates() will be called before leveldb
     //! directories are moved or deleted.
     //!
     //! @sa node/chainstate:LoadChainstate()
     bool ValidatedSnapshotCleanup() EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 };
 
 /** Deployment* info via ChainstateManager */
 template <typename DEP>
 bool DeploymentActiveAfter(const CBlockIndex *pindexPrev,
                            const ChainstateManager &chainman, DEP dep) {
     return DeploymentActiveAfter(pindexPrev, chainman.GetConsensus(), dep);
 }
 
 template <typename DEP>
 bool DeploymentActiveAt(const CBlockIndex &index,
                         const ChainstateManager &chainman, DEP dep) {
     return DeploymentActiveAt(index, chainman.GetConsensus(), dep);
 }
 
 /**
  * Return the expected assumeutxo value for a given height, if one exists.
  *
  * @param[in] height Get the assumeutxo value for this height.
  *
  * @returns empty if no assumeutxo configuration exists for the given height.
  */
 const AssumeutxoData *ExpectedAssumeutxo(const int height,
                                          const CChainParams &params);
 
 #endif // BITCOIN_VALIDATION_H