diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index a22ed6dc3..69254eaa4 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -1,1012 +1,1010 @@
 # Copyright (c) 2017 The Bitcoin developers
 
 project(bitcoind)
 
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
 # Default visibility is hidden on all targets.
 set(CMAKE_C_VISIBILITY_PRESET hidden)
 set(CMAKE_CXX_VISIBILITY_PRESET hidden)
 
 option(BUILD_BITCOIN_WALLET "Activate the wallet functionality" ON)
 option(BUILD_BITCOIN_ZMQ "Activate the ZeroMQ functionalities" ON)
 option(BUILD_BITCOIN_CLI "Build bitcoin-cli" ON)
 option(BUILD_BITCOIN_TX "Build bitcoin-tx" ON)
 option(BUILD_BITCOIN_QT "Build bitcoin-qt" ON)
 option(BUILD_BITCOIN_SEEDER "Build bitcoin-seeder" ON)
 option(BUILD_LIBBITCOINCONSENSUS "Build the bitcoinconsenus shared library" ON)
 option(BUILD_BITCOIN_CHAINSTATE "Build bitcoin-chainstate" OFF)
 option(ENABLE_BIP70 "Enable BIP70 (payment protocol) support in GUI" ON)
 option(ENABLE_HARDENING "Harden the executables" ON)
 option(ENABLE_REDUCE_EXPORTS "Reduce the amount of exported symbols" OFF)
 option(ENABLE_STATIC_LIBSTDCXX "Statically link libstdc++" OFF)
 option(ENABLE_GLIBC_BACK_COMPAT "Enable Glibc compatibility features" OFF)
 option(ENABLE_QRCODE "Enable QR code display" ON)
 option(ENABLE_UPNP "Enable UPnP support" ON)
 option(START_WITH_UPNP "Make UPnP the default to map ports" OFF)
 option(ENABLE_NATPMP "Enable NAT-PMP support" ON)
 option(START_WITH_NATPMP "Make NAT-PMP the default to map ports" OFF)
 option(ENABLE_CLANG_TIDY "Enable clang-tidy checks for Bitcoin ABC" OFF)
 option(ENABLE_PROFILING "Select the profiling tool to use" OFF)
 option(ENABLE_TRACING "Enable eBPF user static defined tracepoints" OFF)
 
 # Linker option
 if(CMAKE_CROSSCOMPILING)
 	set(DEFAULT_LINKER "")
 elseif(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
 	set(DEFAULT_LINKER lld)
 elseif(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
 	set(DEFAULT_LINKER gold)
 else()
 	set(DEFAULT_LINKER "")
 endif()
 set(USE_LINKER "${DEFAULT_LINKER}" CACHE STRING "Linker to be used (default: ${DEFAULT_LINKER}). Set to empty string to use the system's default.")
 
 set(OS_WITH_JEMALLOC_AS_SYSTEM_DEFAULT
 	"Android"
 	"FreeBSD"
 	"NetBSD"
 )
 if(NOT CMAKE_SYSTEM_NAME IN_LIST OS_WITH_JEMALLOC_AS_SYSTEM_DEFAULT)
 	set(USE_JEMALLOC_DEFAULT ON)
 endif()
 
 # FIXME: Building against jemalloc causes the software to segfault on OSX.
 # See https://github.com/Bitcoin-ABC/bitcoin-abc/issues/401
 if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin" AND NOT CMAKE_CROSSCOMPILING)
 	set(USE_JEMALLOC_DEFAULT OFF)
 endif()
 
 option(USE_JEMALLOC "Use jemalloc as an allocation library" ${USE_JEMALLOC_DEFAULT})
 
 if(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
 	set(DEFAULT_ENABLE_DBUS_NOTIFICATIONS ON)
 endif()
 option(ENABLE_DBUS_NOTIFICATIONS "Enable DBus desktop notifications. Linux only." ${DEFAULT_ENABLE_DBUS_NOTIFICATIONS})
 
 # If ccache is available, then use it.
 find_program(CCACHE ccache)
 if(CCACHE)
 	message(STATUS "Using ccache: ${CCACHE}")
 	set(CMAKE_C_COMPILER_LAUNCHER ${CCACHE})
 	set(CMAKE_CXX_COMPILER_LAUNCHER ${CCACHE})
 endif(CCACHE)
 
 # Disable what we do not need for the native build.
 include(NativeExecutable)
 native_add_cmake_flags(
 	"-DBUILD_BITCOIN_WALLET=OFF"
 	"-DBUILD_BITCOIN_CHRONIK=OFF"
 	"-DBUILD_BITCOIN_QT=OFF"
 	"-DBUILD_BITCOIN_ZMQ=OFF"
 	"-DENABLE_QRCODE=OFF"
 	"-DENABLE_NATPMP=OFF"
 	"-DENABLE_UPNP=OFF"
 	"-DUSE_JEMALLOC=OFF"
 	"-DENABLE_CLANG_TIDY=OFF"
 	"-DENABLE_BIP70=OFF"
 	"-DUSE_LINKER="
 )
 
 if(ENABLE_CLANG_TIDY)
 	include(ClangTidy)
 endif()
 
 if(ENABLE_SANITIZERS)
 	include(Sanitizers)
 	enable_sanitizers(${ENABLE_SANITIZERS})
 endif()
 
 include(AddCompilerFlags)
 
 if(USE_LINKER)
 	set(LINKER_FLAG "-fuse-ld=${USE_LINKER}")
 	custom_check_linker_flag(IS_LINKER_SUPPORTED ${LINKER_FLAG})
 	if(NOT IS_LINKER_SUPPORTED)
 		message(FATAL_ERROR "The ${USE_LINKER} linker is not supported, make sure ${USE_LINKER} is properly installed or use -DUSE_LINKER= to use the system's linker")
 	endif()
 
 	add_linker_flags(${LINKER_FLAG})
 
 	# Remember the selected linker, it will be used for the subsequent
 	# custom_check_linker_flag calls
 	set(GLOBAL_LINKER_FLAGS ${LINKER_FLAG} CACHE INTERNAL "Additional linker flags for flag support checking")
 endif()
 
 # Prefer -g3, defaults to -g if unavailable
 foreach(LANGUAGE C CXX)
 	set(COMPILER_DEBUG_LEVEL -g)
 	check_compiler_flags(G3_IS_SUPPORTED ${LANGUAGE} -g3)
 	if(${G3_IS_SUPPORTED})
 		set(COMPILER_DEBUG_LEVEL -g3)
 	endif()
 	add_compile_options_to_configuration_for_language(Debug ${LANGUAGE} ${COMPILER_DEBUG_LEVEL})
 endforeach()
 
 # Define some debugging symbols when the Debug build type is selected.
 add_compile_definitions_to_configuration(Debug DEBUG DEBUG_LOCKORDER ABORT_ON_FAILED_ASSUME)
 
 # Add -ftrapv when building in Debug
 add_compile_options_to_configuration(Debug -ftrapv)
 
 # All versions of gcc that we commonly use for building are subject to bug
 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90348. To work around that, set
 # -fstack-reuse=none for all gcc builds. (Only gcc understands this flag)
 if(CMAKE_CXX_COMPILER_ID MATCHES "GNU")
 	add_compiler_flags(-fstack-reuse=none)
 endif()
 
 if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 	# Ensure that WINDRES_PREPROC is enabled when using windres.
 	list(APPEND CMAKE_RC_FLAGS "-DWINDRES_PREPROC")
 
 	# Build all static so there is no dll file to distribute.
 	add_linker_flags(-static)
 
 	add_compile_definitions(
 		# Windows 7
 		_WIN32_WINNT=0x0601
 		# Internet Explorer 5.01 (!)
 		_WIN32_IE=0x0501
 		# Define WIN32_LEAN_AND_MEAN to exclude APIs such as Cryptography, DDE,
 		# RPC, Shell, and Windows Sockets.
 		WIN32_LEAN_AND_MEAN
 	)
 
 	# We require Windows 7 (NT 6.1) or later
 	add_linker_flags(-Wl,--major-subsystem-version,6 -Wl,--minor-subsystem-version,1)
 endif()
 
 if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
 	add_compile_definitions(MAC_OSX OBJC_OLD_DISPATCH_PROTOTYPES=0)
 	add_linker_flags(-Wl,-dead_strip_dylibs)
 endif()
 
 if(ENABLE_REDUCE_EXPORTS)
 	# Default visibility is set by CMAKE_<LANG>_VISIBILITY_PRESET, but this
 	# doesn't tell if the visibility set is effective.
 	# Check if the flag -fvisibility=hidden is supported, as using the hidden
 	# visibility is a requirement to reduce exports.
 	check_compiler_flags(HAS_CXX_FVISIBILITY CXX -fvisibility=hidden)
 	if(NOT HAS_CXX_FVISIBILITY)
 		message(FATAL_ERROR "Cannot set default symbol visibility. Use -DENABLE_REDUCE_EXPORTS=OFF.")
 	endif()
 
 	# Also hide symbols from static libraries
 	add_linker_flags(-Wl,--exclude-libs,libstdc++)
 endif()
 
 # Enable statically linking libstdc++
 if(ENABLE_STATIC_LIBSTDCXX)
 	add_linker_flags(-static-libstdc++)
 endif()
 
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)
 
 if(ENABLE_HARDENING)
 	# Enable stack protection
 	add_cxx_compiler_flags(-fstack-protector-all -Wstack-protector)
 
 	# Enable control-flow enforcement
 	add_cxx_compiler_flags(-fcf-protection=full)
 
 	if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 		# stack-clash-protection does not work properly when building for Windows.
 		# See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90458
 		add_cxx_compiler_flags(-fstack-clash-protection)
 	endif()
 	add_linker_flags(-Wl,-z,noexecstack)
 
 	# Enable some buffer overflow checking, except in -O0 builds which
 	# do not support them
 	add_compiler_flags(-U_FORTIFY_SOURCE)
 	add_compile_options($<$<NOT:$<CONFIG:Debug>>:-D_FORTIFY_SOURCE=2>)
 
 	# Enable ASLR (these flags are primarily targeting MinGw)
 	add_linker_flags(-Wl,--enable-reloc-section -Wl,--dynamicbase -Wl,--nxcompat -Wl,--high-entropy-va)
 
 	# Make the relocated sections read-only
 	add_linker_flags(-Wl,-z,relro -Wl,-z,now)
 
 	# Avoids mixing code pages with data to improve cache performance as well
 	# as security
 	add_linker_flags(-Wl,-z,separate-code)
 
 	# CMake provides the POSITION_INDEPENDENT_CODE property to set PIC/PIE.
 	cmake_policy(SET CMP0083 NEW)
 	include(CheckPIESupported)
 	check_pie_supported()
 
 	if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 		# MinGw provides its own libssp for stack smashing protection
 		link_libraries(ssp)
 	endif()
 endif()
 
 if(ENABLE_PROFILING MATCHES "gprof")
 	message(STATUS "Enable profiling with gprof")
 
 	# -pg is incompatible with -pie. Since hardening and profiling together
 	# doesn't make sense, we simply make them mutually exclusive here.
 	# Additionally, hardened toolchains may force -pie by default, in which
 	# case it needs to be turned off with -no-pie.
 	if(ENABLE_HARDENING)
 		message(FATAL_ERROR "Profiling with gprof requires disabling hardening with -DENABLE_HARDENING=OFF.")
 	endif()
 	add_linker_flags(-no-pie)
 
 	add_compiler_flags(-pg)
 	add_linker_flags(-pg)
 endif()
 
 # Enable warning
 add_c_compiler_flags(-Wnested-externs -Wstrict-prototypes)
 add_compiler_flags(
 	-Wall
 	-Wextra
 	-Wformat
 	-Wgnu
 	-Wvla
 	-Wcast-align
 	-Wunused-parameter
 	-Wmissing-braces
 	-Wthread-safety
 	-Wrange-loop-analysis
 	-Wredundant-decls
 	-Wunreachable-code-loop-increment
 	-Wsign-compare
 	-Wconditional-uninitialized
 	-Wduplicated-branches
 	-Wduplicated-cond
 	-Wlogical-op
 	-Wdocumentation
 )
 add_compiler_flag_group(-Wformat -Wformat-security)
 add_cxx_compiler_flags(
 	-Wredundant-move
 	-Woverloaded-virtual
 )
 
 if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
 	# GCC has no flag variant which is granular enough to avoid raising the clang
 	# -Wshadow-uncaptured-local equivalent. This is causing a lot of warnings
 	# on serialize.h which cannot be disabled locally, so drop the flag.
 	add_compiler_flags(
 		-Wshadow
 		-Wshadow-field
 	)
 endif()
 
 option(EXTRA_WARNINGS "Enable extra warnings" OFF)
 if(EXTRA_WARNINGS)
 	add_cxx_compiler_flags(-Wsuggest-override)
 else()
 	add_compiler_flags(
 		-Wno-unused-parameter
 		-Wno-implicit-fallthrough
 		-Wno-psabi
 	)
 endif()
 
 # libtool style configure
 add_subdirectory(config)
 
 # Enable LFS (Large File Support) on targets that don't have it natively.
 # This should be defined before the libraries are included as leveldb need the
 # definition to be set.
 if(NOT HAVE_LARGE_FILE_SUPPORT)
 	add_compile_definitions(_FILE_OFFSET_BITS=64)
 	add_linker_flags(-Wl,--large-address-aware)
 endif()
 
 if(ENABLE_GLIBC_BACK_COMPAT)
 	# Wrap some glibc functions with ours
 	add_linker_flags(-Wl,--wrap=exp)
 	add_linker_flags(-Wl,--wrap=log)
 	add_linker_flags(-Wl,--wrap=log2)
 	add_linker_flags(-Wl,--wrap=pow)
 
 	if(NOT HAVE_LARGE_FILE_SUPPORT)
 		add_linker_flags(-Wl,--wrap=fcntl -Wl,--wrap=fcntl64)
 	endif()
 endif()
 
 if(USE_JEMALLOC)
 	# Most of the sanitizers require their instrumented allocation functions to
 	# be fully functional. This is obviously the case for all the memory related
 	# sanitizers (asan, lsan, msan) but not only.
 	if(ENABLE_SANITIZERS)
 		message(WARNING "Jemalloc is incompatible with the sanitizers and has been disabled.")
 	else()
 		find_package(Jemalloc 3.6.0 REQUIRED)
 		link_libraries(Jemalloc::jemalloc)
 	endif()
 endif()
 
 # These flags are needed for using std::filesystem with GCC < 9.1 & Clang < 9.0
 # Since these are optional libraries they need to be placed accordingly on the
 # command line.
 add_linker_flags(-lstdc++fs -lc++fs)
 custom_check_linker_flag(LINKER_HAS_STDCXXFS "-lstdc++fs")
 if(LINKER_HAS_STDCXXFS)
     link_libraries(stdc++fs)
 endif()
 custom_check_linker_flag(LINKER_HAS_CXXFS "-lc++fs")
 if(LINKER_HAS_CXXFS)
     link_libraries(c++fs)
 endif()
 
 
 # Make sure that all the global compiler and linker flags are set BEFORE
 # including the libraries so they apply as needed.
 
 
 # libraries
 add_subdirectory(crypto)
 add_subdirectory(leveldb)
 add_subdirectory(secp256k1)
 add_subdirectory(univalue)
 
 # Find the git root, and returns the full path to the .git/logs/HEAD file if
 # it exists.
 function(find_git_head_logs_file RESULT)
 	find_package(Git)
 	if(GIT_FOUND)
 		execute_process(
 			COMMAND "${GIT_EXECUTABLE}" "rev-parse" "--show-toplevel"
 			WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
 			OUTPUT_VARIABLE GIT_ROOT
 			RESULT_VARIABLE GIT_RESULT
 			OUTPUT_STRIP_TRAILING_WHITESPACE
 			ERROR_QUIET
 		)
 
 		if(GIT_RESULT EQUAL 0)
 			set(GIT_LOGS_DIR "${GIT_ROOT}/.git/logs")
 			set(GIT_HEAD_LOGS_FILE "${GIT_LOGS_DIR}/HEAD")
 			# If the .git/logs/HEAD does not exist, create it
 			if(NOT EXISTS "${GIT_HEAD_LOGS_FILE}")
 				file(MAKE_DIRECTORY "${GIT_LOGS_DIR}")
 				file(TOUCH "${GIT_HEAD_LOGS_FILE}")
 			endif()
 			set(${RESULT} "${GIT_HEAD_LOGS_FILE}" PARENT_SCOPE)
 		endif()
 	endif()
 endfunction()
 
 find_git_head_logs_file(GIT_HEAD_LOGS_FILE)
 
 set(OBJ_DIR "${CMAKE_CURRENT_BINARY_DIR}/obj")
 file(MAKE_DIRECTORY "${OBJ_DIR}")
 set(BUILD_HEADER "${OBJ_DIR}/build.h")
 set(BUILD_HEADER_TMP "${BUILD_HEADER}.tmp")
 
 add_custom_command(
 	DEPENDS
 		"${GIT_HEAD_LOGS_FILE}"
 		"${CMAKE_SOURCE_DIR}/share/genbuild.sh"
 	OUTPUT
 		"${BUILD_HEADER}"
 	COMMAND
 		"${CMAKE_SOURCE_DIR}/share/genbuild.sh"
 		"${BUILD_HEADER_TMP}"
 		"${CMAKE_SOURCE_DIR}"
 	COMMAND
 		${CMAKE_COMMAND} -E copy_if_different "${BUILD_HEADER_TMP}" "${BUILD_HEADER}"
 	COMMAND
 		${CMAKE_COMMAND} -E remove "${BUILD_HEADER_TMP}"
 )
 
 # Because the Bitcoin ABc source code is disorganised, we
 # end up with a bunch of libraries without any apparent
 # cohesive structure. This is inherited from Bitcoin Core
 # and reflecting this.
 # TODO: Improve the structure once cmake is rocking.
 
 # Various completely unrelated features shared by all executables.
 add_library(util
 	chainparamsbase.cpp
 	clientversion.cpp
 	compat/glibcxx_sanity.cpp
 	compat/strnlen.cpp
 	currencyunit.cpp
 	fs.cpp
 	interfaces/handler.cpp
 	logging.cpp
 	random.cpp
 	randomenv.cpp
 	rcu.cpp
 	rpc/request.cpp
 	support/cleanse.cpp
 	support/lockedpool.cpp
 	sync.cpp
 	threadinterrupt.cpp
 	uint256.cpp
 	util/asmap.cpp
 	util/bip32.cpp
 	util/bytevectorhash.cpp
 	util/check.cpp
 	util/hasher.cpp
 	util/error.cpp
 	util/getuniquepath.cpp
 	util/message.cpp
 	util/moneystr.cpp
 	util/readwritefile.cpp
 	util/settings.cpp
 	util/string.cpp
 	util/sock.cpp
 	util/spanparsing.cpp
 	util/strencodings.cpp
 	util/string.cpp
 	util/system.cpp
 	util/thread.cpp
 	util/threadnames.cpp
 	util/time.cpp
 	util/tokenpipe.cpp
 	util/url.cpp
 
 	# obj/build.h
 	"${BUILD_HEADER}"
 )
 
 target_compile_definitions(util PUBLIC HAVE_CONFIG_H HAVE_BUILD_INFO)
 target_include_directories(util
 	PUBLIC
 		.
 		# To access the config/ and obj/ directories
 		${CMAKE_CURRENT_BINARY_DIR}
 )
 
 if(ENABLE_GLIBC_BACK_COMPAT)
 	target_sources(util PRIVATE compat/glibc_compat.cpp)
 endif()
 
 # Work around jemalloc printing harmless warnings to stderr with qemu.
 # We match the emulator against qemu but not ^qemu so we are compatible with the
 # use of absolute paths.
 if(CMAKE_CROSSCOMPILING AND USE_JEMALLOC AND CMAKE_CROSSCOMPILING_EMULATOR MATCHES "qemu-.+")
 	message(WARNING "Overriding Jemalloc malloc_message() function for use with QEMU.")
 	target_sources(util PRIVATE jemalloc_message.cpp)
 endif()
 
 set(Boost_USE_STATIC_LIBS ON)
 
 macro(link_windows_dependencies TARGET)
 	find_package(SHLWAPI REQUIRED)
 	target_link_libraries(${TARGET} SHLWAPI::shlwapi)
 
 	find_library(WS2_32_LIBRARY NAMES ws2_32)
 	target_link_libraries(${TARGET} ${WS2_32_LIBRARY})
 endmacro()
 
 # Target specific configs
 if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 	set(Boost_USE_STATIC_RUNTIME ON)
 	set(Boost_THREADAPI win32)
 
 	link_windows_dependencies(util)
 endif()
 
 target_link_libraries(util univalue crypto)
 
 macro(link_event TARGET)
 	non_native_target_link_libraries(${TARGET} Event 2.0.22 ${ARGN})
 endmacro()
 
 link_event(util event)
 
 macro(link_boost_headers_only TARGET)
 	non_native_target_link_headers_only(${TARGET} Boost 1.64 ${ARGN})
 endmacro()
 
 link_boost_headers_only(util headers)
 
 set(THREADS_PREFER_PTHREAD_FLAG ON)
 find_package(Threads REQUIRED)
 target_link_libraries(util Threads::Threads)
 
 function(add_network_sources NETWORK_SOURCES)
 	set(NETWORK_DIR abc)
 
 	list(TRANSFORM
 		ARGN
 		PREPEND "networks/${NETWORK_DIR}/"
 		OUTPUT_VARIABLE NETWORK_SOURCES
 	)
 	set(NETWORK_SOURCES ${NETWORK_SOURCES} PARENT_SCOPE)
 endfunction()
 
 add_network_sources(NETWORK_SOURCES
 	checkpoints.cpp
 	chainparamsconstants.cpp
 )
 
 # More completely unrelated features shared by all executables.
 # Because nothing says this is different from util than "common"
 add_library(common
 	base58.cpp
 	common/bloom.cpp
 	cashaddr.cpp
 	cashaddrenc.cpp
 	chainparams.cpp
 	config.cpp
 	consensus/merkle.cpp
 	coins.cpp
 	compressor.cpp
 	eventloop.cpp
 	feerate.cpp
 	core_read.cpp
 	core_write.cpp
 	key.cpp
 	key_io.cpp
 	merkleblock.cpp
 	net_permissions.cpp
 	netaddress.cpp
 	netbase.cpp
 	outputtype.cpp
 	policy/policy.cpp
 	primitives/block.cpp
 	protocol.cpp
 	psbt.cpp
 	rpc/rawtransaction_util.cpp
 	rpc/util.cpp
 	scheduler.cpp
 	warnings.cpp
 
 	${NETWORK_SOURCES}
 )
 
 target_link_libraries(common bitcoinconsensus util secp256k1 script)
 
 # script library
 add_library(script
 	script/bitfield.cpp
 	script/descriptor.cpp
 	script/interpreter.cpp
 	script/script.cpp
 	script/script_error.cpp
 	script/sigencoding.cpp
 	script/sign.cpp
 	script/signingprovider.cpp
 	script/standard.cpp
 )
 
 target_link_libraries(script common)
 
 # libbitcoinconsensus
 add_library(bitcoinconsensus
 	arith_uint256.cpp
 	hash.cpp
 	primitives/transaction.cpp
 	pubkey.cpp
 	uint256.cpp
 	util/strencodings.cpp
 	consensus/amount.cpp
 	consensus/tx_check.cpp
 )
 
 target_link_libraries(bitcoinconsensus script)
 
 include(InstallationHelper)
 if(BUILD_LIBBITCOINCONSENSUS)
 	target_compile_definitions(bitcoinconsensus
 		PUBLIC
 			BUILD_BITCOIN_INTERNAL
 			HAVE_CONSENSUS_LIB
 	)
 
 	install_shared_library(bitcoinconsensus
 		script/bitcoinconsensus.cpp
 		PUBLIC_HEADER script/bitcoinconsensus.h
 	)
 endif()
 
 # Bitcoin server facilities
 add_library(server
 	addrdb.cpp
 	addrman.cpp
 	avalanche/avalanche.cpp
 	avalanche/compactproofs.cpp
 	avalanche/delegation.cpp
 	avalanche/delegationbuilder.cpp
 	avalanche/peermanager.cpp
 	avalanche/processor.cpp
 	avalanche/proof.cpp
 	avalanche/proofid.cpp
 	avalanche/proofbuilder.cpp
 	avalanche/proofpool.cpp
 	avalanche/voterecord.cpp
 	banman.cpp
 	blockencodings.cpp
 	blockfileinfo.cpp
 	blockfilter.cpp
 	blockindex.cpp
 	chain.cpp
 	checkpoints.cpp
 	config.cpp
 	consensus/activation.cpp
 	consensus/tx_verify.cpp
 	dbwrapper.cpp
 	deploymentstatus.cpp
 	dnsseeds.cpp
 	flatfile.cpp
 	headerssync.cpp
 	httprpc.cpp
 	httpserver.cpp
 	i2p.cpp
 	index/base.cpp
 	index/blockfilterindex.cpp
 	index/coinstatsindex.cpp
 	index/txindex.cpp
 	init.cpp
 	init/common.cpp
 	invrequest.cpp
 	kernel/cs_main.cpp
 	kernel/disconnected_transactions.cpp
 	kernel/mempool_persist.cpp
 	mapport.cpp
 	mempool_args.cpp
 	minerfund.cpp
 	net.cpp
 	net_processing.cpp
 	node/blockmanager_args.cpp
 	node/blockstorage.cpp
 	node/caches.cpp
 	node/chainstate.cpp
 	node/chainstatemanager_args.cpp
 	node/coin.cpp
 	node/coinstats.cpp
 	node/context.cpp
 	node/interfaces.cpp
 	node/mempool_persist_args.cpp
 	node/miner.cpp
 	node/psbt.cpp
 	node/transaction.cpp
 	node/ui_interface.cpp
 	node/utxo_snapshot.cpp
 	node/validation_cache_args.cpp
 	noui.cpp
 	policy/block/minerfund.cpp
 	policy/block/preconsensus.cpp
 	policy/block/stakingrewards.cpp
 	policy/fees.cpp
 	policy/packages.cpp
 	policy/settings.cpp
 	pow/aserti32d.cpp
 	pow/daa.cpp
 	pow/eda.cpp
 	pow/grasberg.cpp
 	pow/pow.cpp
 	rest.cpp
 	rpc/abc.cpp
 	rpc/avalanche.cpp
 	rpc/blockchain.cpp
 	rpc/command.cpp
 	rpc/mempool.cpp
 	rpc/mining.cpp
 	rpc/misc.cpp
 	rpc/net.cpp
 	rpc/rawtransaction.cpp
 	rpc/server.cpp
 	rpc/server_util.cpp
 	rpc/txoutproof.cpp
 	script/scriptcache.cpp
 	script/sigcache.cpp
 	shutdown.cpp
 	timedata.cpp
 	torcontrol.cpp
 	txdb.cpp
 	txmempool.cpp
 	txorphanage.cpp
 	validation.cpp
 	validationinterface.cpp
 	versionbits.cpp
 )
 
 target_include_directories(server PRIVATE leveldb/helpers/memenv)
 
 target_link_libraries(server
 	bitcoinconsensus
 	leveldb
 	memenv
 )
 
 link_event(server event)
 if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 	link_event(server pthreads)
 endif()
 
 if(ENABLE_UPNP)
 	find_package(MiniUPnPc 1.9 REQUIRED)
 	target_link_libraries(server MiniUPnPc::miniupnpc)
 
 	if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 		# TODO: check if we are really using a static library. Assume this is
 		# the one from the depends for now since the native windows build is not
 		# supported.
 		target_compile_definitions(server
 			PUBLIC -DSTATICLIB
 			PUBLIC -DMINIUPNP_STATICLIB
 		)
 	endif()
 endif()
 
 if(ENABLE_NATPMP)
 	find_package(NATPMP REQUIRED)
 	target_link_libraries(server NATPMP::natpmp)
 
 	if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 		target_compile_definitions(server
 			PUBLIC -DSTATICLIB
 			PUBLIC -DNATPMP_STATICLIB
 		)
 	endif()
 endif()
 
 # Test suites.
 add_subdirectory(test)
 add_subdirectory(avalanche/test)
 add_subdirectory(pow/test)
 
 # Benchmark suite.
 add_subdirectory(bench)
 
 include(BinaryTest)
 include(WindowsVersionInfo)
 
 # Wallet
 if(BUILD_BITCOIN_WALLET)
 	add_subdirectory(wallet)
 	target_link_libraries(server wallet)
 
 	# bitcoin-wallet
 	add_executable(bitcoin-wallet bitcoin-wallet.cpp)
 	generate_windows_version_info(bitcoin-wallet
 		DESCRIPTION "CLI tool for ${PACKAGE_NAME} wallets"
 	)
 
 	target_link_libraries(bitcoin-wallet wallet-tool common util)
 
 	add_to_symbols_check(bitcoin-wallet)
 	add_to_security_check(bitcoin-wallet)
 
 	install_target(bitcoin-wallet)
 	install_manpages(bitcoin-wallet)
 else()
 	target_sources(server PRIVATE dummywallet.cpp)
 endif()
 
 # ZeroMQ
 if(BUILD_BITCOIN_ZMQ)
 	add_subdirectory(zmq)
 	target_link_libraries(server zmq)
 
 	# FIXME: This is needed because of an unwanted dependency:
 	# zmqpublishnotifier.cpp -> blockstorage.h -> txdb.h -> dbwrapper.h -> leveldb/db.h
 	target_link_libraries(zmq leveldb)
 endif()
 
 # RPC client support
 add_library(rpcclient
 	compat/stdin.cpp
 	rpc/client.cpp
 )
 
 target_link_libraries(rpcclient univalue util)
 
 # bitcoin-seeder
 if(BUILD_BITCOIN_SEEDER)
 	add_subdirectory(seeder)
 endif()
 
 # bitcoin-cli
 if(BUILD_BITCOIN_CLI)
 	add_executable(bitcoin-cli bitcoin-cli.cpp)
 	generate_windows_version_info(bitcoin-cli
 		DESCRIPTION "JSON-RPC client for ${PACKAGE_NAME}"
 	)
 
 	target_link_libraries(bitcoin-cli common rpcclient)
 	link_event(bitcoin-cli event)
 
 	add_to_symbols_check(bitcoin-cli)
 	add_to_security_check(bitcoin-cli)
 
 	install_target(bitcoin-cli)
 	install_manpages(bitcoin-cli)
 endif()
 
 # bitcoin-tx
 if(BUILD_BITCOIN_TX)
 	add_executable(bitcoin-tx bitcoin-tx.cpp)
 	generate_windows_version_info(bitcoin-tx
 		DESCRIPTION "CLI Bitcoin transaction editor utility"
 	)
 
 	target_link_libraries(bitcoin-tx bitcoinconsensus)
 
 	add_to_symbols_check(bitcoin-tx)
 	add_to_security_check(bitcoin-tx)
 
 	install_target(bitcoin-tx)
 	install_manpages(bitcoin-tx)
 endif()
 
 # bitcoin-chainstate
 if(BUILD_BITCOIN_CHAINSTATE)
 	# TODO: libbitcoinkernel is a work in progress consensus engine library, as more
 	#       and more modules are decoupled from the consensus engine, this list will
 	#       shrink to only those which are absolutely necessary. For example, things
 	#       like index/*.cpp will be removed.
 	add_library(bitcoinkernel
 		kernel/bitcoinkernel.cpp
 		kernel/cs_main.cpp
 		kernel/disconnected_transactions.cpp
 		kernel/mempool_persist.cpp
 		arith_uint256.cpp
 		blockfileinfo.cpp
-		blockfilter.cpp
 		blockindex.cpp
 		common/bloom.cpp
 		chain.cpp
 		chainparamsbase.cpp
 		chainparams.cpp
 		checkpoints.cpp
 		clientversion.cpp
 		coins.cpp
 		compat/glibcxx_sanity.cpp
 		compressor.cpp
 		config.cpp
 		consensus/activation.cpp
 		consensus/amount.cpp
 		consensus/merkle.cpp
 		consensus/tx_check.cpp
 		consensus/tx_verify.cpp
 		core_read.cpp
 		dbwrapper.cpp
 		deploymentstatus.cpp
 		eventloop.cpp
 		feerate.cpp
 		flatfile.cpp
 		fs.cpp
 		hash.cpp
 		index/base.cpp
-		index/blockfilterindex.cpp
 		index/coinstatsindex.cpp
 		init/common.cpp
 		key.cpp
 		logging.cpp
 		networks/abc/chainparamsconstants.cpp
 		networks/abc/checkpoints.cpp
 		node/blockstorage.cpp
 		node/chainstate.cpp
 		node/coinstats.cpp
 		node/ui_interface.cpp
 		node/utxo_snapshot.cpp
 		policy/fees.cpp
 		policy/packages.cpp
 		policy/policy.cpp
 		policy/settings.cpp
 		pow/aserti32d.cpp
 		pow/daa.cpp
 		pow/eda.cpp
 		pow/pow.cpp
 		primitives/block.cpp
 		primitives/transaction.cpp
 		pubkey.cpp
 		random.cpp
 		randomenv.cpp
 		rcu.cpp
 		scheduler.cpp
 		script/bitfield.cpp
 		script/interpreter.cpp
 		script/script.cpp
 		script/scriptcache.cpp
 		script/script_error.cpp
 		script/sigcache.cpp
 		script/sigencoding.cpp
 		script/standard.cpp
 		shutdown.cpp
 		support/cleanse.cpp
 		support/lockedpool.cpp
 		sync.cpp
 		threadinterrupt.cpp
 		txdb.cpp
 		txmempool.cpp
 		uint256.cpp
 		util/bytevectorhash.cpp
 		util/check.cpp
 		util/getuniquepath.cpp
 		util/hasher.cpp
 		util/moneystr.cpp
 		util/settings.cpp
 		util/strencodings.cpp
 		util/string.cpp
 		util/system.cpp
 		util/thread.cpp
 		util/threadnames.cpp
 		util/time.cpp
 		util/tokenpipe.cpp
 		validation.cpp
 		validationinterface.cpp
 		versionbits.cpp
 		warnings.cpp
 
 		# Bitcoin ABC specific dependencies that will not go away with Core backports
 		addrdb.cpp   # via banman.cpp
 		addrman.cpp  # via net.cpp
 		banman.cpp   # via net.cpp
 		base58.cpp   # via key_io.cpp
 		avalanche/avalanche.cpp
 		avalanche/delegation.cpp
 		avalanche/delegationbuilder.cpp
 		avalanche/peermanager.cpp
 		avalanche/processor.cpp
 		avalanche/proof.cpp
 		avalanche/proofid.cpp
 		avalanche/proofpool.cpp
 		avalanche/voterecord.cpp
 		cashaddr.cpp         # via cashaddrenc.cpp
 		cashaddrenc.cpp      # via key_io.cpp
 		dnsseeds.cpp         # via net.cpp (GetRandomizedDNSSeeds)
 		i2p.cpp              # via net.cppTx
 		key_io.cpp           # avalanche/processor.cpp uses DecodeSecret
 		minerfund.cpp        # via policy/block/minerfund.cpp
 		net.cpp              # avalanche uses CConnman
 		netaddress.cpp       # via net.cpp
 		netbase.cpp          # via net.cpp
 		net_permissions.cpp  # via net.cpp
 		policy/block/minerfund.cpp
 		policy/block/preconsensus.cpp
 		policy/block/stakingrewards.cpp
 		protocol.cpp            # avalanche/processor.cpp uses NetMsgType
 		timedata.cpp            # via net.cpp
 		util/asmap.cpp          # via netaddress.cpp
 		util/error.cpp          # via net_permissions.cpp (ResolveErrMsg)
 		util/readwritefile.cpp  # via i2p.cpp
 		util/sock.cpp           # via net.cpp
 	)
 
 	target_include_directories(bitcoinkernel
 		PUBLIC
 			.
 			leveldb/helpers/memenv
 			# To access the config/ and obj/ directories
 			${CMAKE_CURRENT_BINARY_DIR}
 	)
 	target_link_libraries(bitcoinkernel crypto univalue secp256k1 leveldb memenv)
 	link_boost_headers_only(bitcoinkernel headers)
 
 	if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 		link_windows_dependencies(bitcoinkernel)
 	endif()
 
 	add_executable(bitcoin-chainstate bitcoin-chainstate.cpp)
 
 	target_link_libraries(bitcoin-chainstate bitcoinkernel)
 
 	generate_windows_version_info(bitcoin-chainstate
 		DESCRIPTION "CLI Datadir information utility (experimental)"
 	)
 
 	add_to_symbols_check(bitcoin-chainstate)
 	add_to_security_check(bitcoin-chainstate)
 endif()
 
 # bitcoind
 add_executable(bitcoind bitcoind.cpp)
 target_link_libraries(bitcoind server)
 generate_windows_version_info(bitcoind
 	DESCRIPTION "Bitcoin node with a JSON-RPC server"
 )
 add_to_symbols_check(bitcoind)
 add_to_security_check(bitcoind)
 
 install_target(bitcoind)
 install_manpages(bitcoind)
 
 # Bitcoin-qt
 if(BUILD_BITCOIN_QT)
 	add_subdirectory(qt)
 endif()
diff --git a/src/index/base.cpp b/src/index/base.cpp
index 203a79181..6bd2048cc 100644
--- a/src/index/base.cpp
+++ b/src/index/base.cpp
@@ -1,394 +1,417 @@
 // Copyright (c) 2017-2018 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 <chain.h>
 #include <chainparams.h>
 #include <config.h>
 #include <index/base.h>
 #include <node/blockstorage.h>
 #include <node/ui_interface.h>
 #include <shutdown.h>
 #include <tinyformat.h>
 #include <util/thread.h>
 #include <util/translation.h>
 #include <validation.h> // For Chainstate
 #include <warnings.h>
 
 #include <functional>
 
 using node::ReadBlockFromDisk;
 
 constexpr uint8_t DB_BEST_BLOCK{'B'};
 
 constexpr int64_t SYNC_LOG_INTERVAL = 30;           // secon
 constexpr int64_t SYNC_LOCATOR_WRITE_INTERVAL = 30; // seconds
 
 template <typename... Args>
 static void FatalError(const char *fmt, const Args &...args) {
     std::string strMessage = tfm::format(fmt, args...);
     SetMiscWarning(Untranslated(strMessage));
     LogPrintf("*** %s\n", strMessage);
     AbortError(_("A fatal internal error occurred, see debug.log for details"));
     StartShutdown();
 }
 
 BaseIndex::DB::DB(const fs::path &path, size_t n_cache_size, bool f_memory,
                   bool f_wipe, bool f_obfuscate)
     : CDBWrapper(path, n_cache_size, f_memory, f_wipe, f_obfuscate) {}
 
 bool BaseIndex::DB::ReadBestBlock(CBlockLocator &locator) const {
     bool success = Read(DB_BEST_BLOCK, locator);
     if (!success) {
         locator.SetNull();
     }
     return success;
 }
 
 void BaseIndex::DB::WriteBestBlock(CDBBatch &batch,
                                    const CBlockLocator &locator) {
     batch.Write(DB_BEST_BLOCK, locator);
 }
 
 BaseIndex::~BaseIndex() {
     Interrupt();
     Stop();
 }
 
 bool BaseIndex::Init() {
     CBlockLocator locator;
     if (!GetDB().ReadBestBlock(locator)) {
         locator.SetNull();
     }
 
     LOCK(cs_main);
     CChain &active_chain = m_chainstate->m_chain;
     if (locator.IsNull()) {
-        m_best_block_index = nullptr;
+        SetBestBlockIndex(nullptr);
     } else {
-        m_best_block_index = m_chainstate->FindForkInGlobalIndex(locator);
+        SetBestBlockIndex(m_chainstate->FindForkInGlobalIndex(locator));
     }
     m_synced = m_best_block_index.load() == active_chain.Tip();
     if (!m_synced) {
         bool prune_violation = false;
         if (!m_best_block_index) {
             // index is not built yet
             // make sure we have all block data back to the genesis
             prune_violation = node::GetFirstStoredBlock(active_chain.Tip()) !=
                               active_chain.Genesis();
         }
         // in case the index has a best block set and is not fully synced
         // check if we have the required blocks to continue building the index
         else {
             const CBlockIndex *block_to_test = m_best_block_index.load();
             if (!active_chain.Contains(block_to_test)) {
                 // if the bestblock is not part of the mainchain, find the fork
                 // and make sure we have all data down to the fork
                 block_to_test = active_chain.FindFork(block_to_test);
             }
             const CBlockIndex *block = active_chain.Tip();
             prune_violation = true;
             // check backwards from the tip if we have all block data until we
             // reach the indexes bestblock
             while (block_to_test && block && block->nStatus.hasData()) {
                 if (block_to_test == block) {
                     prune_violation = false;
                     break;
                 }
                 // block->pprev must exist at this point, since block_to_test is
                 // part of the chain and thus must be encountered when going
                 // backwards from the tip
                 assert(block->pprev);
                 block = block->pprev;
             }
         }
         if (prune_violation) {
             return InitError(strprintf(
                 Untranslated("%s best block of the index goes beyond pruned "
                              "data. Please disable the index or reindex (which "
                              "will download the whole blockchain again)"),
                 GetName()));
         }
     }
     return true;
 }
 
 static const CBlockIndex *NextSyncBlock(const CBlockIndex *pindex_prev,
                                         CChain &chain)
     EXCLUSIVE_LOCKS_REQUIRED(cs_main) {
     AssertLockHeld(cs_main);
 
     if (!pindex_prev) {
         return chain.Genesis();
     }
 
     const CBlockIndex *pindex = chain.Next(pindex_prev);
     if (pindex) {
         return pindex;
     }
 
     return chain.Next(chain.FindFork(pindex_prev));
 }
 
 void BaseIndex::ThreadSync() {
     const CBlockIndex *pindex = m_best_block_index.load();
     if (!m_synced) {
         auto &consensus_params = GetConfig().GetChainParams().GetConsensus();
 
         int64_t last_log_time = 0;
         int64_t last_locator_write_time = 0;
         while (true) {
             if (m_interrupt) {
-                m_best_block_index = pindex;
+                SetBestBlockIndex(pindex);
                 // No need to handle errors in Commit. If it fails, the error
                 // will be already be logged. The best way to recover is to
                 // continue, as index cannot be corrupted by a missed commit to
                 // disk for an advanced index state.
                 Commit();
                 return;
             }
 
             {
                 LOCK(cs_main);
                 const CBlockIndex *pindex_next =
                     NextSyncBlock(pindex, m_chainstate->m_chain);
                 if (!pindex_next) {
-                    m_best_block_index = pindex;
+                    SetBestBlockIndex(pindex);
                     m_synced = true;
                     // No need to handle errors in Commit. See rationale above.
                     Commit();
                     break;
                 }
                 if (pindex_next->pprev != pindex &&
                     !Rewind(pindex, pindex_next->pprev)) {
                     FatalError(
                         "%s: Failed to rewind index %s to a previous chain tip",
                         __func__, GetName());
                     return;
                 }
                 pindex = pindex_next;
             }
 
             int64_t current_time = GetTime();
             if (last_log_time + SYNC_LOG_INTERVAL < current_time) {
                 LogPrintf("Syncing %s with block chain from height %d\n",
                           GetName(), pindex->nHeight);
                 last_log_time = current_time;
             }
 
             if (last_locator_write_time + SYNC_LOCATOR_WRITE_INTERVAL <
                 current_time) {
-                m_best_block_index = pindex;
+                SetBestBlockIndex(pindex);
                 last_locator_write_time = current_time;
                 // No need to handle errors in Commit. See rationale above.
                 Commit();
             }
 
             CBlock block;
             if (!ReadBlockFromDisk(block, pindex, consensus_params)) {
                 FatalError("%s: Failed to read block %s from disk", __func__,
                            pindex->GetBlockHash().ToString());
                 return;
             }
             if (!WriteBlock(block, pindex)) {
                 FatalError("%s: Failed to write block %s to index database",
                            __func__, pindex->GetBlockHash().ToString());
                 return;
             }
         }
     }
 
     if (pindex) {
         LogPrintf("%s is enabled at height %d\n", GetName(), pindex->nHeight);
     } else {
         LogPrintf("%s is enabled\n", GetName());
     }
 }
 
 bool BaseIndex::Commit() {
     CDBBatch batch(GetDB());
     if (!CommitInternal(batch) || !GetDB().WriteBatch(batch)) {
         return error("%s: Failed to commit latest %s state", __func__,
                      GetName());
     }
     return true;
 }
 
 bool BaseIndex::CommitInternal(CDBBatch &batch) {
     LOCK(cs_main);
     // Don't commit anything if we haven't indexed any block yet
     // (this could happen if init is interrupted).
     if (m_best_block_index == nullptr) {
         return false;
     }
     GetDB().WriteBestBlock(batch, GetLocator(m_best_block_index));
     return true;
 }
 
 bool BaseIndex::Rewind(const CBlockIndex *current_tip,
                        const CBlockIndex *new_tip) {
     assert(current_tip == m_best_block_index);
     assert(current_tip->GetAncestor(new_tip->nHeight) == new_tip);
 
     // In the case of a reorg, ensure persisted block locator is not stale.
     // Pruning has a minimum of 288 blocks-to-keep and getting the index
     // out of sync may be possible but a users fault.
     // In case we reorg beyond the pruned depth, ReadBlockFromDisk would
     // throw and lead to a graceful shutdown
-    m_best_block_index = new_tip;
+    SetBestBlockIndex(new_tip);
     if (!Commit()) {
         // If commit fails, revert the best block index to avoid corruption.
-        m_best_block_index = current_tip;
+        SetBestBlockIndex(current_tip);
         return false;
     }
 
     return true;
 }
 
 void BaseIndex::BlockConnected(const std::shared_ptr<const CBlock> &block,
                                const CBlockIndex *pindex) {
     if (!m_synced) {
         return;
     }
 
     const CBlockIndex *best_block_index = m_best_block_index.load();
     if (!best_block_index) {
         if (pindex->nHeight != 0) {
             FatalError("%s: First block connected is not the genesis block "
                        "(height=%d)",
                        __func__, pindex->nHeight);
             return;
         }
     } else {
         // Ensure block connects to an ancestor of the current best block. This
         // should be the case most of the time, but may not be immediately after
         // the the sync thread catches up and sets m_synced. Consider the case
         // where there is a reorg and the blocks on the stale branch are in the
         // ValidationInterface queue backlog even after the sync thread has
         // caught up to the new chain tip. In this unlikely event, log a warning
         // and let the queue clear.
         if (best_block_index->GetAncestor(pindex->nHeight - 1) !=
             pindex->pprev) {
             LogPrintf("%s: WARNING: Block %s does not connect to an ancestor "
                       "of known best chain (tip=%s); not updating index\n",
                       __func__, pindex->GetBlockHash().ToString(),
                       best_block_index->GetBlockHash().ToString());
             return;
         }
         if (best_block_index != pindex->pprev &&
             !Rewind(best_block_index, pindex->pprev)) {
             FatalError("%s: Failed to rewind index %s to a previous chain tip",
                        __func__, GetName());
             return;
         }
     }
 
     if (WriteBlock(*block, pindex)) {
-        m_best_block_index = pindex;
+        // Setting the best block index is intentionally the last step of this
+        // function, so BlockUntilSyncedToCurrentChain callers waiting for the
+        // best block index to be updated can rely on the block being fully
+        // processed, and the index object being safe to delete.
+        SetBestBlockIndex(pindex);
     } else {
         FatalError("%s: Failed to write block %s to index", __func__,
                    pindex->GetBlockHash().ToString());
         return;
     }
 }
 
 void BaseIndex::ChainStateFlushed(const CBlockLocator &locator) {
     if (!m_synced) {
         return;
     }
 
     const BlockHash &locator_tip_hash = locator.vHave.front();
     const CBlockIndex *locator_tip_index;
     {
         LOCK(cs_main);
         locator_tip_index =
             m_chainstate->m_blockman.LookupBlockIndex(locator_tip_hash);
     }
 
     if (!locator_tip_index) {
         FatalError("%s: First block (hash=%s) in locator was not found",
                    __func__, locator_tip_hash.ToString());
         return;
     }
 
     // This checks that ChainStateFlushed callbacks are received after
     // BlockConnected. The check may fail immediately after the the sync thread
     // catches up and sets m_synced. Consider the case where there is a reorg
     // and the blocks on the stale branch are in the ValidationInterface queue
     // backlog even after the sync thread has caught up to the new chain tip. In
     // this unlikely event, log a warning and let the queue clear.
     const CBlockIndex *best_block_index = m_best_block_index.load();
     if (best_block_index->GetAncestor(locator_tip_index->nHeight) !=
         locator_tip_index) {
         LogPrintf("%s: WARNING: Locator contains block (hash=%s) not on known "
                   "best chain (tip=%s); not writing index locator\n",
                   __func__, locator_tip_hash.ToString(),
                   best_block_index->GetBlockHash().ToString());
         return;
     }
 
     // No need to handle errors in Commit. If it fails, the error will be
     // already be logged. The best way to recover is to continue, as index
     // cannot be corrupted by a missed commit to disk for an advanced index
     // state.
     Commit();
 }
 
 bool BaseIndex::BlockUntilSyncedToCurrentChain() const {
     AssertLockNotHeld(cs_main);
 
     if (!m_synced) {
         return false;
     }
 
     {
         // Skip the queue-draining stuff if we know we're caught up with
         // m_chain.Tip().
         LOCK(cs_main);
         const CBlockIndex *chain_tip = m_chainstate->m_chain.Tip();
         const CBlockIndex *best_block_index = m_best_block_index.load();
         if (best_block_index->GetAncestor(chain_tip->nHeight) == chain_tip) {
             return true;
         }
     }
 
     LogPrintf("%s: %s is catching up on block notifications\n", __func__,
               GetName());
     SyncWithValidationInterfaceQueue();
     return true;
 }
 
 void BaseIndex::Interrupt() {
     m_interrupt();
 }
 
 bool BaseIndex::Start(Chainstate &active_chainstate) {
     m_chainstate = &active_chainstate;
     // Need to register this ValidationInterface before running Init(), so that
     // callbacks are not missed if Init sets m_synced to true.
     RegisterValidationInterface(this);
     if (!Init()) {
         return false;
     }
 
     m_thread_sync =
         std::thread(&util::TraceThread, GetName(), [this] { ThreadSync(); });
     return true;
 }
 
 void BaseIndex::Stop() {
     UnregisterValidationInterface(this);
 
     if (m_thread_sync.joinable()) {
         m_thread_sync.join();
     }
 }
 
 IndexSummary BaseIndex::GetSummary() const {
     IndexSummary summary{};
     summary.name = GetName();
     summary.synced = m_synced;
     summary.best_block_height =
         m_best_block_index ? m_best_block_index.load()->nHeight : 0;
     return summary;
 }
+
+void BaseIndex::SetBestBlockIndex(const CBlockIndex *block) {
+    assert(!m_chainstate->m_blockman.IsPruneMode() || AllowPrune());
+
+    if (AllowPrune() && block) {
+        node::PruneLockInfo prune_lock;
+        prune_lock.height_first = block->nHeight;
+        WITH_LOCK(::cs_main, m_chainstate->m_blockman.UpdatePruneLock(
+                                 GetName(), prune_lock));
+    }
+
+    // Intentionally set m_best_block_index as the last step in this function,
+    // after updating prune locks above, and after making any other references
+    // to *this, so the BlockUntilSyncedToCurrentChain function (which checks
+    // m_best_block_index as an optimization) can be used to wait for the last
+    // BlockConnected notification and safely assume that prune locks are
+    // updated and that the index object is safe to delete.
+    m_best_block_index = block;
+}
diff --git a/src/index/base.h b/src/index/base.h
index 999a60757..b5900fadb 100644
--- a/src/index/base.h
+++ b/src/index/base.h
@@ -1,135 +1,140 @@
 // Copyright (c) 2017-2018 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_INDEX_BASE_H
 #define BITCOIN_INDEX_BASE_H
 
 #include <dbwrapper.h>
 #include <threadinterrupt.h>
 #include <validationinterface.h>
 
 class CBlock;
 class CBlockIndex;
 class Chainstate;
 
 struct IndexSummary {
     std::string name;
     bool synced{false};
     int best_block_height{0};
 };
 
 /**
  * Base class for indices of blockchain data. This implements
  * CValidationInterface and ensures blocks are indexed sequentially according
  * to their position in the active chain.
  */
 class BaseIndex : public CValidationInterface {
 protected:
     /**
      * The database stores a block locator of the chain the database is synced
      * to so that the TxIndex can efficiently determine the point it last
      * stopped at. A locator is used instead of a simple hash of the chain tip
      * because blocks and block index entries may not be flushed to disk until
      * after this database is updated.
      */
     class DB : public CDBWrapper {
     public:
         DB(const fs::path &path, size_t n_cache_size, bool f_memory = false,
            bool f_wipe = false, bool f_obfuscate = false);
 
         /// Read block locator of the chain that the index is in sync with.
         bool ReadBestBlock(CBlockLocator &locator) const;
 
         /// Write block locator of the chain that the index is in sync with.
         void WriteBestBlock(CDBBatch &batch, const CBlockLocator &locator);
     };
 
 private:
     /// Whether the index is in sync with the main chain. The flag is flipped
     /// from false to true once, after which point this starts processing
     /// ValidationInterface notifications to stay in sync.
     std::atomic<bool> m_synced{false};
 
     /// The last block in the chain that the index is in sync with.
     std::atomic<const CBlockIndex *> m_best_block_index{nullptr};
 
     std::thread m_thread_sync;
     CThreadInterrupt m_interrupt;
 
     /// Sync the index with the block index starting from the current best
     /// block. Intended to be run in its own thread, m_thread_sync, and can be
     /// interrupted with m_interrupt. Once the index gets in sync, the m_synced
     /// flag is set and the BlockConnected ValidationInterface callback takes
     /// over and the sync thread exits.
     void ThreadSync();
 
     /// Write the current index state (eg. chain block locator and
     /// subclass-specific items) to disk.
     ///
     /// Recommendations for error handling:
     /// If called on a successor of the previous committed best block in the
     /// index, the index can continue processing without risk of corruption,
     /// though the index state will need to catch up from further behind on
     /// reboot. If the new state is not a successor of the previous state (due
     /// to a chain reorganization), the index must halt until Commit succeeds or
     /// else it could end up getting corrupted.
     bool Commit();
 
+    virtual bool AllowPrune() const = 0;
+
 protected:
     Chainstate *m_chainstate{nullptr};
 
     void BlockConnected(const std::shared_ptr<const CBlock> &block,
                         const CBlockIndex *pindex) override;
 
     void ChainStateFlushed(const CBlockLocator &locator) override;
 
     const CBlockIndex *CurrentIndex() { return m_best_block_index.load(); };
 
     /// Initialize internal state from the database and block index.
     [[nodiscard]] virtual bool Init();
 
     /// Write update index entries for a newly connected block.
     virtual bool WriteBlock(const CBlock &block, const CBlockIndex *pindex) {
         return true;
     }
 
     /// Virtual method called internally by Commit that can be overridden to
     /// atomically commit more index state.
     virtual bool CommitInternal(CDBBatch &batch);
 
     /// Rewind index to an earlier chain tip during a chain reorg. The tip must
     /// be an ancestor of the current best block.
     virtual bool Rewind(const CBlockIndex *current_tip,
                         const CBlockIndex *new_tip);
 
     virtual DB &GetDB() const = 0;
 
     /// Get the name of the index for display in logs.
     virtual const char *GetName() const = 0;
 
+    /// Update the internal best block index as well as the prune lock.
+    void SetBestBlockIndex(const CBlockIndex *block);
+
 public:
     /// Destructor interrupts sync thread if running and blocks until it exits.
     virtual ~BaseIndex();
 
     /// Blocks the current thread until the index is caught up to the current
     /// state of the block chain. This only blocks if the index has gotten in
     /// sync once and only needs to process blocks in the ValidationInterface
     /// queue. If the index is catching up from far behind, this method does
     /// not block and immediately returns false.
     bool BlockUntilSyncedToCurrentChain() const LOCKS_EXCLUDED(::cs_main);
 
     void Interrupt();
 
     /// Start initializes the sync state and registers the instance as a
     /// ValidationInterface so that it stays in sync with blockchain updates.
     [[nodiscard]] bool Start(Chainstate &active_chainstate);
 
     /// Stops the instance from staying in sync with blockchain updates.
     void Stop();
 
     /// Get a summary of the index and its state.
     IndexSummary GetSummary() const;
 };
 
 #endif // BITCOIN_INDEX_BASE_H
diff --git a/src/index/blockfilterindex.h b/src/index/blockfilterindex.h
index d6a89769f..585b15fb3 100644
--- a/src/index/blockfilterindex.h
+++ b/src/index/blockfilterindex.h
@@ -1,112 +1,114 @@
 // Copyright (c) 2018 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_INDEX_BLOCKFILTERINDEX_H
 #define BITCOIN_INDEX_BLOCKFILTERINDEX_H
 
 #include <blockfilter.h>
 #include <chain.h>
 #include <flatfile.h>
 #include <index/base.h>
 #include <util/hasher.h>
 
 static const char *const DEFAULT_BLOCKFILTERINDEX = "0";
 
 /** Interval between compact filter checkpoints. See BIP 157. */
 static constexpr int CFCHECKPT_INTERVAL = 1000;
 
 /**
  * BlockFilterIndex is used to store and retrieve block filters, hashes, and
  * headers for a range of blocks by height. An index is constructed for each
  * supported filter type with its own database (ie. filter data for different
  * types are stored in separate databases).
  *
  * This index is used to serve BIP 157 net requests.
  */
 class BlockFilterIndex final : public BaseIndex {
 private:
     BlockFilterType m_filter_type;
     std::string m_name;
     std::unique_ptr<BaseIndex::DB> m_db;
 
     FlatFilePos m_next_filter_pos;
     std::unique_ptr<FlatFileSeq> m_filter_fileseq;
 
     bool ReadFilterFromDisk(const FlatFilePos &pos, BlockFilter &filter) const;
     size_t WriteFilterToDisk(FlatFilePos &pos, const BlockFilter &filter);
 
     Mutex m_cs_headers_cache;
     /**
      * Cache of block hash to filter header, to avoid disk access when
      * responding to getcfcheckpt.
      */
     std::unordered_map<BlockHash, uint256, FilterHeaderHasher>
         m_headers_cache GUARDED_BY(m_cs_headers_cache);
 
+    bool AllowPrune() const override { return true; }
+
 protected:
     bool Init() override;
 
     bool CommitInternal(CDBBatch &batch) override;
 
     bool WriteBlock(const CBlock &block, const CBlockIndex *pindex) override;
 
     bool Rewind(const CBlockIndex *current_tip,
                 const CBlockIndex *new_tip) override;
 
     BaseIndex::DB &GetDB() const override { return *m_db; }
 
     const char *GetName() const override { return m_name.c_str(); }
 
 public:
     /** Constructs the index, which becomes available to be queried. */
     explicit BlockFilterIndex(BlockFilterType filter_type, size_t n_cache_size,
                               bool f_memory = false, bool f_wipe = false);
 
     BlockFilterType GetFilterType() const { return m_filter_type; }
 
     /** Get a single filter by block. */
     bool LookupFilter(const CBlockIndex *block_index,
                       BlockFilter &filter_out) const;
 
     /** Get a single filter header by block. */
     bool LookupFilterHeader(const CBlockIndex *block_index, uint256 &header_out)
         EXCLUSIVE_LOCKS_REQUIRED(!m_cs_headers_cache);
 
     /** Get a range of filters between two heights on a chain. */
     bool LookupFilterRange(int start_height, const CBlockIndex *stop_index,
                            std::vector<BlockFilter> &filters_out) const;
 
     /** Get a range of filter hashes between two heights on a chain. */
     bool LookupFilterHashRange(int start_height, const CBlockIndex *stop_index,
                                std::vector<uint256> &hashes_out) const;
 };
 
 /**
  * Get a block filter index by type. Returns nullptr if index has not been
  * initialized or was already destroyed.
  */
 BlockFilterIndex *GetBlockFilterIndex(BlockFilterType filter_type);
 
 /** Iterate over all running block filter indexes, invoking fn on each. */
 void ForEachBlockFilterIndex(std::function<void(BlockFilterIndex &)> fn);
 
 /**
  * Initialize a block filter index for the given type if one does not already
  * exist. Returns true if a new index is created and false if one has already
  * been initialized.
  */
 bool InitBlockFilterIndex(BlockFilterType filter_type, size_t n_cache_size,
                           bool f_memory = false, bool f_wipe = false);
 
 /**
  * Destroy the block filter index with the given type. Returns false if no such
  * index exists. This just releases the allocated memory and closes the database
  * connection, it does not delete the index data.
  */
 bool DestroyBlockFilterIndex(BlockFilterType filter_type);
 
 /** Destroy all open block filter indexes. */
 void DestroyAllBlockFilterIndexes();
 
 #endif // BITCOIN_INDEX_BLOCKFILTERINDEX_H
diff --git a/src/index/coinstatsindex.h b/src/index/coinstatsindex.h
index 0ad1c8d25..53a1c9236 100644
--- a/src/index/coinstatsindex.h
+++ b/src/index/coinstatsindex.h
@@ -1,69 +1,71 @@
 // Copyright (c) 2020-2021 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_INDEX_COINSTATSINDEX_H
 #define BITCOIN_INDEX_COINSTATSINDEX_H
 
 #include <chain.h>
 #include <crypto/muhash.h>
 #include <flatfile.h>
 #include <index/base.h>
 #include <node/coinstats.h>
 
 struct Amount;
 
 static constexpr bool DEFAULT_COINSTATSINDEX{false};
 
 /**
  * CoinStatsIndex maintains statistics on the UTXO set.
  */
 class CoinStatsIndex final : public BaseIndex {
 private:
     std::string m_name;
     std::unique_ptr<BaseIndex::DB> m_db;
 
     MuHash3072 m_muhash;
     uint64_t m_transaction_output_count{0};
     uint64_t m_bogo_size{0};
     Amount m_total_amount{Amount::zero()};
     Amount m_total_subsidy{Amount::zero()};
     Amount m_total_unspendable_amount{Amount::zero()};
     Amount m_total_prevout_spent_amount{Amount::zero()};
     Amount m_total_new_outputs_ex_coinbase_amount{Amount::zero()};
     Amount m_total_coinbase_amount{Amount::zero()};
     Amount m_total_unspendables_genesis_block{Amount::zero()};
     Amount m_total_unspendables_bip30{Amount::zero()};
     Amount m_total_unspendables_scripts{Amount::zero()};
     Amount m_total_unspendables_unclaimed_rewards{Amount::zero()};
 
     bool ReverseBlock(const CBlock &block, const CBlockIndex *pindex);
 
+    bool AllowPrune() const override { return true; }
+
 protected:
     bool Init() override;
 
     bool CommitInternal(CDBBatch &batch) override;
 
     bool WriteBlock(const CBlock &block, const CBlockIndex *pindex) override;
 
     bool Rewind(const CBlockIndex *current_tip,
                 const CBlockIndex *new_tip) override;
 
     BaseIndex::DB &GetDB() const override { return *m_db; }
 
     const char *GetName() const override { return "coinstatsindex"; }
 
 public:
     // Constructs the index, which becomes available to be queried.
     explicit CoinStatsIndex(size_t n_cache_size, bool f_memory = false,
                             bool f_wipe = false);
 
     // Look up stats for a specific block using CBlockIndex
     std::optional<node::CCoinsStats>
     LookUpStats(const CBlockIndex *block_index) const;
 };
 
 /// The global UTXO set hash object.
 extern std::unique_ptr<CoinStatsIndex> g_coin_stats_index;
 
 #endif // BITCOIN_INDEX_COINSTATSINDEX_H
diff --git a/src/index/txindex.h b/src/index/txindex.h
index 017a0d599..f7c641405 100644
--- a/src/index/txindex.h
+++ b/src/index/txindex.h
@@ -1,59 +1,61 @@
 // Copyright (c) 2017-2018 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_INDEX_TXINDEX_H
 #define BITCOIN_INDEX_TXINDEX_H
 
 #include <index/base.h>
 
 #include <memory>
 
 struct BlockHash;
 struct TxId;
 
 static constexpr bool DEFAULT_TXINDEX{false};
 
 /**
  * TxIndex is used to look up transactions included in the blockchain by ID.
  * The index is written to a LevelDB database and records the filesystem
  * location of each transaction by transaction ID.
  */
 class TxIndex final : public BaseIndex {
 protected:
     class DB;
 
 private:
     const std::unique_ptr<DB> m_db;
 
+    bool AllowPrune() const override { return false; }
+
 protected:
     bool WriteBlock(const CBlock &block, const CBlockIndex *pindex) override;
 
     BaseIndex::DB &GetDB() const override;
 
     const char *GetName() const override { return "txindex"; }
 
 public:
     /// Constructs the index, which becomes available to be queried.
     explicit TxIndex(size_t n_cache_size, bool f_memory = false,
                      bool f_wipe = false);
 
     // Destructor is declared because this class contains a unique_ptr to an
     // incomplete type.
     virtual ~TxIndex() override;
 
     /// Look up a transaction by identifier.
     ///
     /// @param[in]   txid  The ID of the transaction to be returned.
     /// @param[out]  block_hash  The hash of the block the transaction is found
     /// in.
     /// @param[out]  tx  The transaction itself.
     /// @return  true if transaction is found, false otherwise
     bool FindTx(const TxId &txid, BlockHash &block_hash,
                 CTransactionRef &tx) const;
 };
 
 /// The global transaction index, used in GetTransaction. May be null.
 extern std::unique_ptr<TxIndex> g_txindex;
 
 #endif // BITCOIN_INDEX_TXINDEX_H
diff --git a/src/node/blockstorage.cpp b/src/node/blockstorage.cpp
index d2b5137fc..e8274306b 100644
--- a/src/node/blockstorage.cpp
+++ b/src/node/blockstorage.cpp
@@ -1,999 +1,1005 @@
 // Copyright (c) 2011-2022 The Bitcoin developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <node/blockstorage.h>
 
 #include <blockindexcomparators.h>
 #include <chain.h>
 #include <chainparams.h>
 #include <clientversion.h>
 #include <config.h>
 #include <consensus/validation.h>
 #include <flatfile.h>
 #include <fs.h>
 #include <hash.h>
 #include <pow/pow.h>
 #include <reverse_iterator.h>
 #include <shutdown.h>
 #include <streams.h>
 #include <undo.h>
 #include <util/system.h>
 #include <validation.h>
 
 #include <map>
 #include <unordered_map>
 
 namespace node {
 std::atomic_bool fReindex(false);
 
 static FILE *OpenUndoFile(const FlatFilePos &pos, bool fReadOnly = false);
 
 static FlatFileSeq BlockFileSeq();
 static FlatFileSeq UndoFileSeq();
 
 std::vector<CBlockIndex *> BlockManager::GetAllBlockIndices() {
     AssertLockHeld(cs_main);
     std::vector<CBlockIndex *> rv;
     rv.reserve(m_block_index.size());
     for (auto &[_, block_index] : m_block_index) {
         rv.push_back(&block_index);
     }
     return rv;
 }
 
 CBlockIndex *BlockManager::LookupBlockIndex(const BlockHash &hash) {
     AssertLockHeld(cs_main);
     BlockMap::iterator it = m_block_index.find(hash);
     return it == m_block_index.end() ? nullptr : &it->second;
 }
 
 const CBlockIndex *BlockManager::LookupBlockIndex(const BlockHash &hash) const {
     AssertLockHeld(cs_main);
     BlockMap::const_iterator it = m_block_index.find(hash);
     return it == m_block_index.end() ? nullptr : &it->second;
 }
 
 CBlockIndex *BlockManager::AddToBlockIndex(const CBlockHeader &block,
                                            CBlockIndex *&best_header) {
     AssertLockHeld(cs_main);
 
     const auto [mi, inserted] =
         m_block_index.try_emplace(block.GetHash(), block);
     if (!inserted) {
         return &mi->second;
     }
     CBlockIndex *pindexNew = &(*mi).second;
 
     // We assign the sequence id to blocks only when the full data is available,
     // to avoid miners withholding blocks but broadcasting headers, to get a
     // competitive advantage.
     pindexNew->nSequenceId = 0;
 
     pindexNew->phashBlock = &((*mi).first);
     BlockMap::iterator miPrev = m_block_index.find(block.hashPrevBlock);
     if (miPrev != m_block_index.end()) {
         pindexNew->pprev = &(*miPrev).second;
         pindexNew->nHeight = pindexNew->pprev->nHeight + 1;
         pindexNew->BuildSkip();
     }
     pindexNew->nTimeReceived = GetTime();
     pindexNew->nTimeMax =
         (pindexNew->pprev
              ? std::max(pindexNew->pprev->nTimeMax, pindexNew->nTime)
              : pindexNew->nTime);
     pindexNew->nChainWork =
         (pindexNew->pprev ? pindexNew->pprev->nChainWork : 0) +
         GetBlockProof(*pindexNew);
     pindexNew->RaiseValidity(BlockValidity::TREE);
     if (best_header == nullptr ||
         best_header->nChainWork < pindexNew->nChainWork) {
         best_header = pindexNew;
     }
 
     m_dirty_blockindex.insert(pindexNew);
     return pindexNew;
 }
 
 void BlockManager::PruneOneBlockFile(const int fileNumber) {
     AssertLockHeld(cs_main);
     LOCK(cs_LastBlockFile);
 
     for (auto &entry : m_block_index) {
         CBlockIndex *pindex = &entry.second;
         if (pindex->nFile == fileNumber) {
             pindex->nStatus = pindex->nStatus.withData(false).withUndo(false);
             pindex->nFile = 0;
             pindex->nDataPos = 0;
             pindex->nUndoPos = 0;
             m_dirty_blockindex.insert(pindex);
 
             // Prune from m_blocks_unlinked -- any block we prune would have
             // to be downloaded again in order to consider its chain, at which
             // point it would be considered as a candidate for
             // m_blocks_unlinked or setBlockIndexCandidates.
             auto range = m_blocks_unlinked.equal_range(pindex->pprev);
             while (range.first != range.second) {
                 std::multimap<CBlockIndex *, CBlockIndex *>::iterator _it =
                     range.first;
                 range.first++;
                 if (_it->second == pindex) {
                     m_blocks_unlinked.erase(_it);
                 }
             }
         }
     }
 
     m_blockfile_info[fileNumber].SetNull();
     m_dirty_fileinfo.insert(fileNumber);
 }
 
 void BlockManager::FindFilesToPruneManual(std::set<int> &setFilesToPrune,
                                           int nManualPruneHeight,
                                           int chain_tip_height) {
     assert(IsPruneMode() && nManualPruneHeight > 0);
 
     LOCK2(cs_main, cs_LastBlockFile);
     if (chain_tip_height < 0) {
         return;
     }
 
     // last block to prune is the lesser of (user-specified height,
     // MIN_BLOCKS_TO_KEEP from the tip)
     unsigned int nLastBlockWeCanPrune{std::min(
         (unsigned)nManualPruneHeight, chain_tip_height - MIN_BLOCKS_TO_KEEP)};
     int count = 0;
     for (int fileNumber = 0; fileNumber < m_last_blockfile; fileNumber++) {
         if (m_blockfile_info[fileNumber].nSize == 0 ||
             m_blockfile_info[fileNumber].nHeightLast > nLastBlockWeCanPrune) {
             continue;
         }
         PruneOneBlockFile(fileNumber);
         setFilesToPrune.insert(fileNumber);
         count++;
     }
     LogPrintf("Prune (Manual): prune_height=%d removed %d blk/rev pairs\n",
               nLastBlockWeCanPrune, count);
 }
 
 void BlockManager::FindFilesToPrune(std::set<int> &setFilesToPrune,
                                     uint64_t nPruneAfterHeight,
                                     int chain_tip_height, int prune_height,
                                     bool is_ibd) {
     LOCK2(cs_main, cs_LastBlockFile);
     if (chain_tip_height < 0 || GetPruneTarget() == 0) {
         return;
     }
     if (uint64_t(chain_tip_height) <= nPruneAfterHeight) {
         return;
     }
 
     unsigned int nLastBlockWeCanPrune = std::min(
         prune_height, chain_tip_height - static_cast<int>(MIN_BLOCKS_TO_KEEP));
     uint64_t nCurrentUsage = CalculateCurrentUsage();
     // We don't check to prune until after we've allocated new space for files,
     // so we should leave a buffer under our target to account for another
     // allocation before the next pruning.
     uint64_t nBuffer = BLOCKFILE_CHUNK_SIZE + UNDOFILE_CHUNK_SIZE;
     uint64_t nBytesToPrune;
     int count = 0;
 
     if (nCurrentUsage + nBuffer >= GetPruneTarget()) {
         // On a prune event, the chainstate DB is flushed.
         // To avoid excessive prune events negating the benefit of high dbcache
         // values, we should not prune too rapidly.
         // So when pruning in IBD, increase the buffer a bit to avoid a re-prune
         // too soon.
         if (is_ibd) {
             // Since this is only relevant during IBD, we use a fixed 10%
             nBuffer += GetPruneTarget() / 10;
         }
 
         for (int fileNumber = 0; fileNumber < m_last_blockfile; fileNumber++) {
             nBytesToPrune = m_blockfile_info[fileNumber].nSize +
                             m_blockfile_info[fileNumber].nUndoSize;
 
             if (m_blockfile_info[fileNumber].nSize == 0) {
                 continue;
             }
 
             // are we below our target?
             if (nCurrentUsage + nBuffer < GetPruneTarget()) {
                 break;
             }
 
             // don't prune files that could have a block within
             // MIN_BLOCKS_TO_KEEP of the main chain's tip but keep scanning
             if (m_blockfile_info[fileNumber].nHeightLast >
                 nLastBlockWeCanPrune) {
                 continue;
             }
 
             PruneOneBlockFile(fileNumber);
             // Queue up the files for removal
             setFilesToPrune.insert(fileNumber);
             nCurrentUsage -= nBytesToPrune;
             count++;
         }
     }
 
     LogPrint(BCLog::PRUNE,
              "Prune: target=%dMiB actual=%dMiB diff=%dMiB "
              "max_prune_height=%d removed %d blk/rev pairs\n",
              GetPruneTarget() / 1024 / 1024, nCurrentUsage / 1024 / 1024,
              (int64_t(GetPruneTarget()) - int64_t(nCurrentUsage)) / 1024 / 1024,
              nLastBlockWeCanPrune, count);
 }
 
+void BlockManager::UpdatePruneLock(const std::string &name,
+                                   const PruneLockInfo &lock_info) {
+    AssertLockHeld(::cs_main);
+    m_prune_locks[name] = lock_info;
+}
+
 CBlockIndex *BlockManager::InsertBlockIndex(const BlockHash &hash) {
     AssertLockHeld(cs_main);
 
     if (hash.IsNull()) {
         return nullptr;
     }
 
     const auto [mi, inserted] = m_block_index.try_emplace(hash);
     CBlockIndex *pindex = &(*mi).second;
     if (inserted) {
         pindex->phashBlock = &((*mi).first);
     }
     return pindex;
 }
 
 bool BlockManager::LoadBlockIndex() {
     AssertLockHeld(cs_main);
     if (!m_block_tree_db->LoadBlockIndexGuts(
             GetConsensus(),
             [this](const BlockHash &hash) EXCLUSIVE_LOCKS_REQUIRED(cs_main) {
                 return this->InsertBlockIndex(hash);
             })) {
         return false;
     }
 
     // Calculate nChainWork
     std::vector<CBlockIndex *> vSortedByHeight{GetAllBlockIndices()};
     std::sort(vSortedByHeight.begin(), vSortedByHeight.end(),
               CBlockIndexHeightOnlyComparator());
 
     for (CBlockIndex *pindex : vSortedByHeight) {
         if (ShutdownRequested()) {
             return false;
         }
         pindex->nChainWork = (pindex->pprev ? pindex->pprev->nChainWork : 0) +
                              GetBlockProof(*pindex);
         pindex->nTimeMax =
             (pindex->pprev ? std::max(pindex->pprev->nTimeMax, pindex->nTime)
                            : pindex->nTime);
 
         // We can link the chain of blocks for which we've received
         // transactions at some point, or blocks that are assumed-valid on the
         // basis of snapshot load (see PopulateAndValidateSnapshot()).
         // Pruned nodes may have deleted the block.
         if (pindex->nTx > 0) {
             if (!pindex->UpdateChainStats() && pindex->pprev) {
                 m_blocks_unlinked.insert(std::make_pair(pindex->pprev, pindex));
             }
         }
 
         if (!pindex->nStatus.hasFailed() && pindex->pprev &&
             pindex->pprev->nStatus.hasFailed()) {
             pindex->nStatus = pindex->nStatus.withFailedParent();
             m_dirty_blockindex.insert(pindex);
         }
 
         if (pindex->pprev) {
             pindex->BuildSkip();
         }
     }
 
     return true;
 }
 
 bool BlockManager::WriteBlockIndexDB() {
     std::vector<std::pair<int, const CBlockFileInfo *>> vFiles;
     vFiles.reserve(m_dirty_fileinfo.size());
     for (int i : m_dirty_fileinfo) {
         vFiles.push_back(std::make_pair(i, &m_blockfile_info[i]));
     }
 
     m_dirty_fileinfo.clear();
 
     std::vector<const CBlockIndex *> vBlocks;
     vBlocks.reserve(m_dirty_blockindex.size());
     for (const CBlockIndex *cbi : m_dirty_blockindex) {
         vBlocks.push_back(cbi);
     }
 
     m_dirty_blockindex.clear();
 
     if (!m_block_tree_db->WriteBatchSync(vFiles, m_last_blockfile, vBlocks)) {
         return false;
     }
     return true;
 }
 
 bool BlockManager::LoadBlockIndexDB() {
     if (!LoadBlockIndex()) {
         return false;
     }
 
     // Load block file info
     m_block_tree_db->ReadLastBlockFile(m_last_blockfile);
     m_blockfile_info.resize(m_last_blockfile + 1);
     LogPrintf("%s: last block file = %i\n", __func__, m_last_blockfile);
     for (int nFile = 0; nFile <= m_last_blockfile; nFile++) {
         m_block_tree_db->ReadBlockFileInfo(nFile, m_blockfile_info[nFile]);
     }
     LogPrintf("%s: last block file info: %s\n", __func__,
               m_blockfile_info[m_last_blockfile].ToString());
     for (int nFile = m_last_blockfile + 1; true; nFile++) {
         CBlockFileInfo info;
         if (m_block_tree_db->ReadBlockFileInfo(nFile, info)) {
             m_blockfile_info.push_back(info);
         } else {
             break;
         }
     }
 
     // Check presence of blk files
     LogPrintf("Checking all blk files are present...\n");
     std::set<int> setBlkDataFiles;
     for (const auto &[_, block_index] : m_block_index) {
         if (block_index.nStatus.hasData()) {
             setBlkDataFiles.insert(block_index.nFile);
         }
     }
 
     for (const int i : setBlkDataFiles) {
         FlatFilePos pos(i, 0);
         if (CAutoFile(OpenBlockFile(pos, true), SER_DISK, CLIENT_VERSION)
                 .IsNull()) {
             return false;
         }
     }
 
     // Check whether we have ever pruned block & undo files
     m_block_tree_db->ReadFlag("prunedblockfiles", m_have_pruned);
     if (m_have_pruned) {
         LogPrintf(
             "LoadBlockIndexDB(): Block files have previously been pruned\n");
     }
 
     // Check whether we need to continue reindexing
     if (m_block_tree_db->IsReindexing()) {
         fReindex = true;
     }
 
     return true;
 }
 
 const CBlockIndex *
 BlockManager::GetLastCheckpoint(const CCheckpointData &data) {
     const MapCheckpoints &checkpoints = data.mapCheckpoints;
 
     for (const MapCheckpoints::value_type &i : reverse_iterate(checkpoints)) {
         const BlockHash &hash = i.second;
         const CBlockIndex *pindex = LookupBlockIndex(hash);
         if (pindex) {
             return pindex;
         }
     }
 
     return nullptr;
 }
 
 bool BlockManager::IsBlockPruned(const CBlockIndex *pblockindex) {
     AssertLockHeld(::cs_main);
     return (m_have_pruned && !pblockindex->nStatus.hasData() &&
             pblockindex->nTx > 0);
 }
 
 const CBlockIndex *GetFirstStoredBlock(const CBlockIndex *start_block) {
     AssertLockHeld(::cs_main);
     assert(start_block);
     const CBlockIndex *last_block = start_block;
     while (last_block->pprev && (last_block->pprev->nStatus.hasData())) {
         last_block = last_block->pprev;
     }
     return last_block;
 }
 
 // If we're using -prune with -reindex, then delete block files that will be
 // ignored by the reindex.  Since reindexing works by starting at block file 0
 // and looping until a blockfile is missing, do the same here to delete any
 // later block files after a gap. Also delete all rev files since they'll be
 // rewritten by the reindex anyway. This ensures that m_blockfile_info is in
 // sync with what's actually on disk by the time we start downloading, so that
 // pruning works correctly.
 void CleanupBlockRevFiles() {
     std::map<std::string, fs::path> mapBlockFiles;
 
     // Glob all blk?????.dat and rev?????.dat files from the blocks directory.
     // Remove the rev files immediately and insert the blk file paths into an
     // ordered map keyed by block file index.
     LogPrintf("Removing unusable blk?????.dat and rev?????.dat files for "
               "-reindex with -prune\n");
     for (const auto &file : fs::directory_iterator{gArgs.GetBlocksDirPath()}) {
         const std::string path = fs::PathToString(file.path().filename());
         if (fs::is_regular_file(file) && path.length() == 12 &&
             path.substr(8, 4) == ".dat") {
             if (path.substr(0, 3) == "blk") {
                 mapBlockFiles[path.substr(3, 5)] = file.path();
             } else if (path.substr(0, 3) == "rev") {
                 remove(file.path());
             }
         }
     }
 
     // Remove all block files that aren't part of a contiguous set starting at
     // zero by walking the ordered map (keys are block file indices) by keeping
     // a separate counter. Once we hit a gap (or if 0 doesn't exist) start
     // removing block files.
     int contiguousCounter = 0;
     for (const auto &item : mapBlockFiles) {
         if (atoi(item.first) == contiguousCounter) {
             contiguousCounter++;
             continue;
         }
         remove(item.second);
     }
 }
 
 CBlockFileInfo *BlockManager::GetBlockFileInfo(size_t n) {
     LOCK(cs_LastBlockFile);
 
     return &m_blockfile_info.at(n);
 }
 
 static bool UndoWriteToDisk(const CBlockUndo &blockundo, FlatFilePos &pos,
                             const BlockHash &hashBlock,
                             const CMessageHeader::MessageMagic &messageStart) {
     // Open history file to append
     CAutoFile fileout(OpenUndoFile(pos), SER_DISK, CLIENT_VERSION);
     if (fileout.IsNull()) {
         return error("%s: OpenUndoFile failed", __func__);
     }
 
     // Write index header
     unsigned int nSize = GetSerializeSize(blockundo, fileout.GetVersion());
     fileout << messageStart << nSize;
 
     // Write undo data
     long fileOutPos = ftell(fileout.Get());
     if (fileOutPos < 0) {
         return error("%s: ftell failed", __func__);
     }
     pos.nPos = (unsigned int)fileOutPos;
     fileout << blockundo;
 
     // calculate & write checksum
     CHashWriter hasher(SER_GETHASH, PROTOCOL_VERSION);
     hasher << hashBlock;
     hasher << blockundo;
     fileout << hasher.GetHash();
 
     return true;
 }
 
 bool UndoReadFromDisk(CBlockUndo &blockundo, const CBlockIndex *pindex) {
     const FlatFilePos pos{WITH_LOCK(::cs_main, return pindex->GetUndoPos())};
 
     if (pos.IsNull()) {
         return error("%s: no undo data available", __func__);
     }
 
     // Open history file to read
     CAutoFile filein(OpenUndoFile(pos, true), SER_DISK, CLIENT_VERSION);
     if (filein.IsNull()) {
         return error("%s: OpenUndoFile failed", __func__);
     }
 
     // Read block
     uint256 hashChecksum;
     // We need a CHashVerifier as reserializing may lose data
     CHashVerifier<CAutoFile> verifier(&filein);
     try {
         verifier << pindex->pprev->GetBlockHash();
         verifier >> blockundo;
         filein >> hashChecksum;
     } catch (const std::exception &e) {
         return error("%s: Deserialize or I/O error - %s", __func__, e.what());
     }
 
     // Verify checksum
     if (hashChecksum != verifier.GetHash()) {
         return error("%s: Checksum mismatch", __func__);
     }
 
     return true;
 }
 
 void BlockManager::FlushUndoFile(int block_file, bool finalize) {
     FlatFilePos undo_pos_old(block_file,
                              m_blockfile_info[block_file].nUndoSize);
     if (!UndoFileSeq().Flush(undo_pos_old, finalize)) {
         AbortNode("Flushing undo file to disk failed. This is likely the "
                   "result of an I/O error.");
     }
 }
 
 void BlockManager::FlushBlockFile(bool fFinalize, bool finalize_undo) {
     LOCK(cs_LastBlockFile);
 
     if (m_blockfile_info.empty()) {
         // Return if we haven't loaded any blockfiles yet. This happens during
         // chainstate init, when we call
         // ChainstateManager::MaybeRebalanceCaches() (which then calls
         // FlushStateToDisk()), resulting in a call to this function before we
         // have populated `m_blockfile_info` via LoadBlockIndexDB().
         return;
     }
     assert(static_cast<int>(m_blockfile_info.size()) > m_last_blockfile);
 
     FlatFilePos block_pos_old(m_last_blockfile,
                               m_blockfile_info[m_last_blockfile].nSize);
     if (!BlockFileSeq().Flush(block_pos_old, fFinalize)) {
         AbortNode("Flushing block file to disk failed. This is likely the "
                   "result of an I/O error.");
     }
     // we do not always flush the undo file, as the chain tip may be lagging
     // behind the incoming blocks,
     // e.g. during IBD or a sync after a node going offline
     if (!fFinalize || finalize_undo) {
         FlushUndoFile(m_last_blockfile, finalize_undo);
     }
 }
 
 uint64_t BlockManager::CalculateCurrentUsage() {
     LOCK(cs_LastBlockFile);
 
     uint64_t retval = 0;
     for (const CBlockFileInfo &file : m_blockfile_info) {
         retval += file.nSize + file.nUndoSize;
     }
 
     return retval;
 }
 
 void UnlinkPrunedFiles(const std::set<int> &setFilesToPrune) {
     for (const int i : setFilesToPrune) {
         FlatFilePos pos(i, 0);
         fs::remove(BlockFileSeq().FileName(pos));
         fs::remove(UndoFileSeq().FileName(pos));
         LogPrint(BCLog::BLOCKSTORE, "Prune: %s deleted blk/rev (%05u)\n",
                  __func__, i);
     }
 }
 
 static FlatFileSeq BlockFileSeq() {
     return FlatFileSeq(gArgs.GetBlocksDirPath(), "blk",
                        gArgs.GetBoolArg("-fastprune", false)
                            ? 0x4000 /* 16kb */
                            : BLOCKFILE_CHUNK_SIZE);
 }
 
 static FlatFileSeq UndoFileSeq() {
     return FlatFileSeq(gArgs.GetBlocksDirPath(), "rev", UNDOFILE_CHUNK_SIZE);
 }
 
 FILE *OpenBlockFile(const FlatFilePos &pos, bool fReadOnly) {
     return BlockFileSeq().Open(pos, fReadOnly);
 }
 
 /** Open an undo file (rev?????.dat) */
 static FILE *OpenUndoFile(const FlatFilePos &pos, bool fReadOnly) {
     return UndoFileSeq().Open(pos, fReadOnly);
 }
 
 fs::path GetBlockPosFilename(const FlatFilePos &pos) {
     return BlockFileSeq().FileName(pos);
 }
 
 bool BlockManager::FindBlockPos(FlatFilePos &pos, unsigned int nAddSize,
                                 unsigned int nHeight, CChain &active_chain,
                                 uint64_t nTime, bool fKnown) {
     LOCK(cs_LastBlockFile);
 
     unsigned int nFile = fKnown ? pos.nFile : m_last_blockfile;
     if (m_blockfile_info.size() <= nFile) {
         m_blockfile_info.resize(nFile + 1);
     }
 
     bool finalize_undo = false;
     if (!fKnown) {
         unsigned int max_blockfile_size{MAX_BLOCKFILE_SIZE};
         // Use smaller blockfiles in test-only -fastprune mode - but avoid
         // the possibility of having a block not fit into the block file.
         if (gArgs.GetBoolArg("-fastprune", false)) {
             max_blockfile_size = 0x10000; // 64kiB
             if (nAddSize >= max_blockfile_size) {
                 // dynamically adjust the blockfile size to be larger than the
                 // added size
                 max_blockfile_size = nAddSize + 1;
             }
         }
         // TODO: we will also need to dynamically adjust the blockfile size
         //   or raise MAX_BLOCKFILE_SIZE when we reach block sizes larger than
         //   128 MiB
         assert(nAddSize < max_blockfile_size);
         while (m_blockfile_info[nFile].nSize + nAddSize >= max_blockfile_size) {
             // when the undo file is keeping up with the block file, we want to
             // flush it explicitly when it is lagging behind (more blocks arrive
             // than are being connected), we let the undo block write case
             // handle it
             finalize_undo = (m_blockfile_info[nFile].nHeightLast ==
                              (unsigned int)active_chain.Tip()->nHeight);
             nFile++;
             if (m_blockfile_info.size() <= nFile) {
                 m_blockfile_info.resize(nFile + 1);
             }
         }
         pos.nFile = nFile;
         pos.nPos = m_blockfile_info[nFile].nSize;
     }
 
     if ((int)nFile != m_last_blockfile) {
         if (!fKnown) {
             LogPrint(BCLog::BLOCKSTORE, "Leaving block file %i: %s\n",
                      m_last_blockfile,
                      m_blockfile_info[m_last_blockfile].ToString());
         }
         FlushBlockFile(!fKnown, finalize_undo);
         m_last_blockfile = nFile;
     }
 
     m_blockfile_info[nFile].AddBlock(nHeight, nTime);
     if (fKnown) {
         m_blockfile_info[nFile].nSize =
             std::max(pos.nPos + nAddSize, m_blockfile_info[nFile].nSize);
     } else {
         m_blockfile_info[nFile].nSize += nAddSize;
     }
 
     if (!fKnown) {
         bool out_of_space;
         size_t bytes_allocated =
             BlockFileSeq().Allocate(pos, nAddSize, out_of_space);
         if (out_of_space) {
             return AbortNode("Disk space is too low!",
                              _("Disk space is too low!"));
         }
         if (bytes_allocated != 0 && IsPruneMode()) {
             m_check_for_pruning = true;
         }
     }
 
     m_dirty_fileinfo.insert(nFile);
     return true;
 }
 
 bool BlockManager::FindUndoPos(BlockValidationState &state, int nFile,
                                FlatFilePos &pos, unsigned int nAddSize) {
     pos.nFile = nFile;
 
     LOCK(cs_LastBlockFile);
 
     pos.nPos = m_blockfile_info[nFile].nUndoSize;
     m_blockfile_info[nFile].nUndoSize += nAddSize;
     m_dirty_fileinfo.insert(nFile);
 
     bool out_of_space;
     size_t bytes_allocated =
         UndoFileSeq().Allocate(pos, nAddSize, out_of_space);
     if (out_of_space) {
         return AbortNode(state, "Disk space is too low!",
                          _("Disk space is too low!"));
     }
     if (bytes_allocated != 0 && IsPruneMode()) {
         m_check_for_pruning = true;
     }
 
     return true;
 }
 
 static bool WriteBlockToDisk(const CBlock &block, FlatFilePos &pos,
                              const CMessageHeader::MessageMagic &messageStart) {
     // Open history file to append
     CAutoFile fileout(OpenBlockFile(pos), SER_DISK, CLIENT_VERSION);
     if (fileout.IsNull()) {
         return error("WriteBlockToDisk: OpenBlockFile failed");
     }
 
     // Write index header
     unsigned int nSize = GetSerializeSize(block, fileout.GetVersion());
     fileout << messageStart << nSize;
 
     // Write block
     long fileOutPos = ftell(fileout.Get());
     if (fileOutPos < 0) {
         return error("WriteBlockToDisk: ftell failed");
     }
 
     pos.nPos = (unsigned int)fileOutPos;
     fileout << block;
 
     return true;
 }
 
 bool BlockManager::WriteUndoDataForBlock(const CBlockUndo &blockundo,
                                          BlockValidationState &state,
                                          CBlockIndex &block) {
     AssertLockHeld(::cs_main);
     // Write undo information to disk
     if (block.GetUndoPos().IsNull()) {
         FlatFilePos _pos;
         if (!FindUndoPos(state, block.nFile, _pos,
                          ::GetSerializeSize(blockundo, CLIENT_VERSION) + 40)) {
             return error("ConnectBlock(): FindUndoPos failed");
         }
         if (!UndoWriteToDisk(blockundo, _pos, block.pprev->GetBlockHash(),
                              GetParams().DiskMagic())) {
             return AbortNode(state, "Failed to write undo data");
         }
         // rev files are written in block height order, whereas blk files are
         // written as blocks come in (often out of order) we want to flush the
         // rev (undo) file once we've written the last block, which is indicated
         // by the last height in the block file info as below; note that this
         // does not catch the case where the undo writes are keeping up with the
         // block writes (usually when a synced up node is getting newly mined
         // blocks) -- this case is caught in the FindBlockPos function
         if (_pos.nFile < m_last_blockfile &&
             static_cast<uint32_t>(block.nHeight) ==
                 m_blockfile_info[_pos.nFile].nHeightLast) {
             FlushUndoFile(_pos.nFile, true);
         }
 
         // update nUndoPos in block index
         block.nUndoPos = _pos.nPos;
         block.nStatus = block.nStatus.withUndo();
         m_dirty_blockindex.insert(&block);
     }
 
     return true;
 }
 
 bool ReadBlockFromDisk(CBlock &block, const FlatFilePos &pos,
                        const Consensus::Params &params) {
     block.SetNull();
 
     // Open history file to read
     CAutoFile filein(OpenBlockFile(pos, true), SER_DISK, CLIENT_VERSION);
     if (filein.IsNull()) {
         return error("ReadBlockFromDisk: OpenBlockFile failed for %s",
                      pos.ToString());
     }
 
     // Read block
     try {
         filein >> block;
     } catch (const std::exception &e) {
         return error("%s: Deserialize or I/O error - %s at %s", __func__,
                      e.what(), pos.ToString());
     }
 
     // Check the header
     if (!CheckProofOfWork(block.GetHash(), block.nBits, params)) {
         return error("ReadBlockFromDisk: Errors in block header at %s",
                      pos.ToString());
     }
 
     return true;
 }
 
 bool ReadBlockFromDisk(CBlock &block, const CBlockIndex *pindex,
                        const Consensus::Params &params) {
     const FlatFilePos block_pos{
         WITH_LOCK(cs_main, return pindex->GetBlockPos())};
 
     if (!ReadBlockFromDisk(block, block_pos, params)) {
         return false;
     }
 
     if (block.GetHash() != pindex->GetBlockHash()) {
         return error("ReadBlockFromDisk(CBlock&, CBlockIndex*): GetHash() "
                      "doesn't match index for %s at %s",
                      pindex->ToString(), block_pos.ToString());
     }
 
     return true;
 }
 
 bool ReadTxFromDisk(CMutableTransaction &tx, const FlatFilePos &pos) {
     // Open history file to read
     CAutoFile filein(OpenBlockFile(pos, true), SER_DISK, CLIENT_VERSION);
     if (filein.IsNull()) {
         return error("ReadTxFromDisk: OpenBlockFile failed for %s",
                      pos.ToString());
     }
 
     // Read tx
     try {
         filein >> tx;
     } catch (const std::exception &e) {
         return error("%s: Deserialize or I/O error - %s at %s", __func__,
                      e.what(), pos.ToString());
     }
 
     return true;
 }
 
 bool ReadTxUndoFromDisk(CTxUndo &tx_undo, const FlatFilePos &pos) {
     // Open undo file to read
     CAutoFile filein(OpenUndoFile(pos, true), SER_DISK, CLIENT_VERSION);
     if (filein.IsNull()) {
         return error("ReadTxUndoFromDisk: OpenUndoFile failed for %s",
                      pos.ToString());
     }
 
     // Read undo data
     try {
         filein >> tx_undo;
     } catch (const std::exception &e) {
         return error("%s: Deserialize or I/O error - %s at %s", __func__,
                      e.what(), pos.ToString());
     }
 
     return true;
 }
 
 FlatFilePos BlockManager::SaveBlockToDisk(const CBlock &block, int nHeight,
                                           CChain &active_chain,
                                           const FlatFilePos *dbp) {
     unsigned int nBlockSize = ::GetSerializeSize(block, CLIENT_VERSION);
     FlatFilePos blockPos;
     const auto position_known{dbp != nullptr};
     if (position_known) {
         blockPos = *dbp;
     } else {
         // When known, blockPos.nPos points at the offset of the block data in
         // the blk file. That already accounts for the serialization header
         // present in the file (the 4 magic message start bytes + the 4 length
         // bytes = 8 bytes = BLOCK_SERIALIZATION_HEADER_SIZE). We add
         // BLOCK_SERIALIZATION_HEADER_SIZE only for new blocks since they will
         // have the serialization header added when written to disk.
         nBlockSize +=
             static_cast<unsigned int>(BLOCK_SERIALIZATION_HEADER_SIZE);
     }
     if (!FindBlockPos(blockPos, nBlockSize, nHeight, active_chain,
                       block.GetBlockTime(), position_known)) {
         error("%s: FindBlockPos failed", __func__);
         return FlatFilePos();
     }
     if (!position_known) {
         if (!WriteBlockToDisk(block, blockPos, GetParams().DiskMagic())) {
             AbortNode("Failed to write block");
             return FlatFilePos();
         }
     }
     return blockPos;
 }
 
 class ImportingNow {
     std::atomic<bool> &m_importing;
 
 public:
     ImportingNow(std::atomic<bool> &importing) : m_importing{importing} {
         assert(m_importing == false);
         m_importing = true;
     }
     ~ImportingNow() {
         assert(m_importing == true);
         m_importing = false;
     }
 };
 
 void ThreadImport(ChainstateManager &chainman,
                   std::vector<fs::path> vImportFiles, const ArgsManager &args,
                   const fs::path &mempool_path) {
     ScheduleBatchPriority();
 
     {
         ImportingNow imp{chainman.m_blockman.m_importing};
 
         // -reindex
         if (fReindex) {
             int nFile = 0;
             // Map of disk positions for blocks with unknown parent (only used
             // for reindex);  parent hash -> child disk position, multiple
             // children can have the same parent.
             std::multimap<BlockHash, FlatFilePos> blocks_with_unknown_parent;
             while (true) {
                 FlatFilePos pos(nFile, 0);
                 if (!fs::exists(GetBlockPosFilename(pos))) {
                     // No block files left to reindex
                     break;
                 }
                 FILE *file = OpenBlockFile(pos, true);
                 if (!file) {
                     // This error is logged in OpenBlockFile
                     break;
                 }
                 LogPrintf("Reindexing block file blk%05u.dat...\n",
                           (unsigned int)nFile);
                 chainman.ActiveChainstate().LoadExternalBlockFile(
                     file, &pos, &blocks_with_unknown_parent);
                 if (ShutdownRequested()) {
                     LogPrintf("Shutdown requested. Exit %s\n", __func__);
                     return;
                 }
                 nFile++;
             }
             WITH_LOCK(
                 ::cs_main,
                 chainman.m_blockman.m_block_tree_db->WriteReindexing(false));
             fReindex = false;
             LogPrintf("Reindexing finished\n");
             // To avoid ending up in a situation without genesis block, re-try
             // initializing (no-op if reindexing worked):
             chainman.ActiveChainstate().LoadGenesisBlock();
         }
 
         // -loadblock=
         for (const fs::path &path : vImportFiles) {
             FILE *file = fsbridge::fopen(path, "rb");
             if (file) {
                 LogPrintf("Importing blocks file %s...\n",
                           fs::PathToString(path));
                 chainman.ActiveChainstate().LoadExternalBlockFile(file);
                 if (ShutdownRequested()) {
                     LogPrintf("Shutdown requested. Exit %s\n", __func__);
                     return;
                 }
             } else {
                 LogPrintf("Warning: Could not open blocks file %s\n",
                           fs::PathToString(path));
             }
         }
 
         // Reconsider blocks we know are valid. They may have been marked
         // invalid by, for instance, running an outdated version of the node
         // software.
         const MapCheckpoints &checkpoints =
             chainman.GetParams().Checkpoints().mapCheckpoints;
         for (const MapCheckpoints::value_type &i : checkpoints) {
             const BlockHash &hash = i.second;
 
             LOCK(cs_main);
             CBlockIndex *pblockindex =
                 chainman.m_blockman.LookupBlockIndex(hash);
             if (pblockindex && !pblockindex->nStatus.isValid()) {
                 LogPrintf("Reconsidering checkpointed block %s ...\n",
                           hash.GetHex());
                 chainman.ActiveChainstate().ResetBlockFailureFlags(pblockindex);
             }
 
             if (pblockindex && pblockindex->nStatus.isOnParkedChain()) {
                 LogPrintf("Unparking checkpointed block %s ...\n",
                           hash.GetHex());
                 chainman.ActiveChainstate().UnparkBlockAndChildren(pblockindex);
             }
         }
 
         // scan for better chains in the block chain database, that are not yet
         // connected in the active best chain
 
         // We can't hold cs_main during ActivateBestChain even though we're
         // accessing the chainman unique_ptrs since ABC requires us not to be
         // holding cs_main, so retrieve the relevant pointers before the ABC
         // call.
         for (Chainstate *chainstate :
              WITH_LOCK(::cs_main, return chainman.GetAll())) {
             BlockValidationState state;
             if (!chainstate->ActivateBestChain(state, nullptr)) {
                 LogPrintf("Failed to connect best block (%s)\n",
                           state.ToString());
                 StartShutdown();
                 return;
             }
         }
 
         if (args.GetBoolArg("-stopafterblockimport",
                             DEFAULT_STOPAFTERBLOCKIMPORT)) {
             LogPrintf("Stopping after block import\n");
             StartShutdown();
             return;
         }
     } // End scope of ImportingNow
     chainman.ActiveChainstate().LoadMempool(mempool_path);
 }
 } // namespace node
diff --git a/src/node/blockstorage.h b/src/node/blockstorage.h
index 57979d280..25f5a3273 100644
--- a/src/node/blockstorage.h
+++ b/src/node/blockstorage.h
@@ -1,275 +1,280 @@
 // Copyright (c) 2011-2021 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_NODE_BLOCKSTORAGE_H
 #define BITCOIN_NODE_BLOCKSTORAGE_H
 
 #include <cstdint>
 #include <unordered_map>
 #include <vector>
 
 #include <chain.h>
 #include <chainparams.h>
 #include <fs.h>
 #include <kernel/blockmanager_opts.h>
 #include <kernel/cs_main.h>
 #include <protocol.h> // For CMessageHeader::MessageStartChars
 #include <sync.h>
 #include <txdb.h>
 
 class ArgsManager;
 class BlockValidationState;
 class CBlock;
 class CBlockFileInfo;
 class CBlockHeader;
 class CBlockUndo;
 class CChain;
 class CChainParams;
 class CTxUndo;
 class Chainstate;
 class ChainstateManager;
 struct CCheckpointData;
 class Config;
 struct FlatFilePos;
 namespace Consensus {
 struct Params;
 }
 
 namespace node {
 static constexpr bool DEFAULT_STOPAFTERBLOCKIMPORT{false};
 
 /** The pre-allocation chunk size for blk?????.dat files (since 0.8) */
 static constexpr unsigned int BLOCKFILE_CHUNK_SIZE = 0x1000000; // 16 MiB
 /** The pre-allocation chunk size for rev?????.dat files (since 0.8) */
 static const unsigned int UNDOFILE_CHUNK_SIZE = 0x100000; // 1 MiB
 /** The maximum size of a blk?????.dat file (since 0.8) */
 static const unsigned int MAX_BLOCKFILE_SIZE = 0x8000000; // 128 MiB
 
 /** Size of header written by WriteBlockToDisk before a serialized CBlock */
 static constexpr size_t BLOCK_SERIALIZATION_HEADER_SIZE =
     CMessageHeader::MESSAGE_START_SIZE + sizeof(unsigned int);
 
 extern std::atomic_bool fReindex;
 
 // Because validation code takes pointers to the map's CBlockIndex objects, if
 // we ever switch to another associative container, we need to either use a
 // container that has stable addressing (true of all std associative
 // containers), or make the key a `std::unique_ptr<CBlockIndex>`
 using BlockMap = std::unordered_map<BlockHash, CBlockIndex, BlockHasher>;
 
 struct PruneLockInfo {
     //! Height of earliest block that should be kept and not pruned
     int height_first{std::numeric_limits<int>::max()};
 };
 
 /**
  * Maintains a tree of blocks (stored in `m_block_index`) which is consulted
  * to determine where the most-work tip is.
  *
  * This data is used mostly in `Chainstate` - information about, e.g.,
  * candidate tips is not maintained here.
  */
 class BlockManager {
     friend Chainstate;
     friend ChainstateManager;
 
 private:
     const CChainParams &GetParams() const { return m_opts.chainparams; }
     const Consensus::Params &GetConsensus() const {
         return m_opts.chainparams.GetConsensus();
     }
     /**
      * Load the blocktree off disk and into memory. Populate certain metadata
      * per index entry (nStatus, nChainWork, nTimeMax, etc.) as well as
      * peripheral collections like m_dirty_blockindex.
      */
     bool LoadBlockIndex() EXCLUSIVE_LOCKS_REQUIRED(cs_main);
     void FlushBlockFile(bool fFinalize = false, bool finalize_undo = false);
     void FlushUndoFile(int block_file, bool finalize = false);
     bool FindBlockPos(FlatFilePos &pos, unsigned int nAddSize,
                       unsigned int nHeight, CChain &active_chain,
                       uint64_t nTime, bool fKnown);
     bool FindUndoPos(BlockValidationState &state, int nFile, FlatFilePos &pos,
                      unsigned int nAddSize);
 
     /**
      * Calculate the block/rev files to delete based on height specified
      * by user with RPC command pruneblockchain
      */
     void FindFilesToPruneManual(std::set<int> &setFilesToPrune,
                                 int nManualPruneHeight, int chain_tip_height);
 
     /**
      * Prune block and undo files (blk???.dat and undo???.dat) so that the disk
      * space used is less than a user-defined target. The user sets the target
      * (in MB) on the command line or in config file.  This will be run on
      * startup and whenever new space is allocated in a block or undo file,
      * staying below the target. Changing back to unpruned requires a reindex
      * (which in this case means the blockchain must be re-downloaded.)
      *
      * Pruning functions are called from FlushStateToDisk when the
      * m_check_for_pruning flag has been set. Block and undo files are deleted
      * in lock-step (when blk00003.dat is deleted, so is rev00003.dat.) Pruning
      * cannot take place until the longest chain is at least a certain length
      * (CChainParams::nPruneAfterHeight). Pruning will never delete a block
      * within a defined distance (currently 288) from the active chain's tip.
      * The block index is updated by unsetting HAVE_DATA and HAVE_UNDO for any
      * blocks that were stored in the deleted files. A db flag records the fact
      * that at least some block files have been pruned.
      *
      * @param[out]   setFilesToPrune   The set of file indices that can be
      *                                 unlinked will be returned
      */
     void FindFilesToPrune(std::set<int> &setFilesToPrune,
                           uint64_t nPruneAfterHeight, int chain_tip_height,
                           int prune_height, bool is_ibd);
 
     RecursiveMutex cs_LastBlockFile;
     std::vector<CBlockFileInfo> m_blockfile_info;
     int m_last_blockfile = 0;
     /**
      * Global flag to indicate we should check to see if there are
      * block/undo files that should be deleted.  Set on startup
      * or if we allocate more file space when we're in prune mode
      */
     bool m_check_for_pruning = false;
 
     const bool m_prune_mode;
 
     /** Dirty block index entries. */
     std::set<CBlockIndex *> m_dirty_blockindex;
 
     /** Dirty block file entries. */
     std::set<int> m_dirty_fileinfo;
 
     /**
      * Map from external index name to oldest block that must not be pruned.
      *
      * @note Internally, only blocks at height
      *     (height_first - PRUNE_LOCK_BUFFER - 1) and below will be pruned,
      *     but callers should avoid assuming any particular buffer size.
      */
     std::unordered_map<std::string, PruneLockInfo>
         m_prune_locks GUARDED_BY(::cs_main);
 
     const kernel::BlockManagerOpts m_opts;
 
 public:
     using Options = kernel::BlockManagerOpts;
 
     explicit BlockManager(Options opts)
         : m_prune_mode{opts.prune_target > 0}, m_opts{std::move(opts)} {};
 
     std::atomic<bool> m_importing{false};
 
     BlockMap m_block_index GUARDED_BY(cs_main);
 
     std::vector<CBlockIndex *> GetAllBlockIndices()
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     /**
      * All pairs A->B, where A (or one of its ancestors) misses transactions,
      * but B has transactions. Pruned nodes may have entries where B is missing
      * data.
      */
     std::multimap<CBlockIndex *, CBlockIndex *> m_blocks_unlinked;
 
     std::unique_ptr<CBlockTreeDB> m_block_tree_db GUARDED_BY(::cs_main);
 
     bool WriteBlockIndexDB() EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
     bool LoadBlockIndexDB() EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     CBlockIndex *AddToBlockIndex(const CBlockHeader &block,
                                  CBlockIndex *&best_header)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
     /** Create a new block index entry for a given block hash */
     CBlockIndex *InsertBlockIndex(const BlockHash &hash)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     //! Mark one block file as pruned (modify associated database entries)
     void PruneOneBlockFile(const int fileNumber)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     CBlockIndex *LookupBlockIndex(const BlockHash &hash)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
     const CBlockIndex *LookupBlockIndex(const BlockHash &hash) const
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     /** Get block file info entry for one block file */
     CBlockFileInfo *GetBlockFileInfo(size_t n);
 
     bool WriteUndoDataForBlock(const CBlockUndo &blockundo,
                                BlockValidationState &state, CBlockIndex &block)
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     /**
      * Store block on disk. If dbp is not nullptr, then it provides the known
      * position of the block within a block file on disk.
      */
     FlatFilePos SaveBlockToDisk(const CBlock &block, int nHeight,
                                 CChain &active_chain, const FlatFilePos *dbp);
 
     /** Whether running in -prune mode. */
     [[nodiscard]] bool IsPruneMode() const { return m_prune_mode; }
 
     /** Attempt to stay below this number of bytes of block files. */
     [[nodiscard]] uint64_t GetPruneTarget() const {
         return m_opts.prune_target;
     }
     static constexpr auto PRUNE_TARGET_MANUAL{
         std::numeric_limits<uint64_t>::max()};
 
     [[nodiscard]] bool LoadingBlocks() const { return m_importing || fReindex; }
 
     /**
      * Calculate the amount of disk space the block & undo files currently use
      */
     uint64_t CalculateCurrentUsage();
 
     //! Returns last CBlockIndex* that is a checkpoint
     const CBlockIndex *GetLastCheckpoint(const CCheckpointData &data)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
     /** True if any block files have ever been pruned. */
     bool m_have_pruned = false;
 
     //! Check whether the block associated with this index entry is pruned or
     //! not.
     bool IsBlockPruned(const CBlockIndex *pblockindex)
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
+
+    //! Create or update a prune lock identified by its name
+    void UpdatePruneLock(const std::string &name,
+                         const PruneLockInfo &lock_info)
+        EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 };
 
 //! Find the first block that is not pruned
 const CBlockIndex *GetFirstStoredBlock(const CBlockIndex *start_block)
     EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
 void CleanupBlockRevFiles();
 
 /** Open a block file (blk?????.dat) */
 FILE *OpenBlockFile(const FlatFilePos &pos, bool fReadOnly = false);
 /** Translation to a filesystem path. */
 fs::path GetBlockPosFilename(const FlatFilePos &pos);
 
 /**
  *  Actually unlink the specified files
  */
 void UnlinkPrunedFiles(const std::set<int> &setFilesToPrune);
 
 /** Functions for disk access for blocks */
 bool ReadBlockFromDisk(CBlock &block, const FlatFilePos &pos,
                        const Consensus::Params &consensusParams);
 bool ReadBlockFromDisk(CBlock &block, const CBlockIndex *pindex,
                        const Consensus::Params &consensusParams);
 bool UndoReadFromDisk(CBlockUndo &blockundo, const CBlockIndex *pindex);
 
 /** Functions for disk access for txs */
 bool ReadTxFromDisk(CMutableTransaction &tx, const FlatFilePos &pos);
 bool ReadTxUndoFromDisk(CTxUndo &tx, const FlatFilePos &pos);
 
 void ThreadImport(ChainstateManager &chainman,
                   std::vector<fs::path> vImportFiles, const ArgsManager &args,
                   const fs::path &mempool_path);
 } // namespace node
 
 #endif // BITCOIN_NODE_BLOCKSTORAGE_H
diff --git a/src/validation.cpp b/src/validation.cpp
index 18708d619..e43a7664b 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -1,6629 +1,6623 @@
 // 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::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",
 };
 /**
  * The number of blocks to keep below the deepest prune lock.
  * There is nothing special about this number. It is higher than what we
  * expect to see in regular mainnet reorgs, but not so high that it would
  * noticeably interfere with the pruning mechanism.
  * */
 static constexpr int PRUNE_LOCK_BUFFER{10};
 
 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.augustoActivationTime);
 }
 
 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(
             *Assert(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)) {
         return false;
     }
 
     if (!pindex->IsValid(BlockValidity::SCRIPTS)) {
         pindex->RaiseValidity(BlockValidity::SCRIPTS);
         m_blockman.m_dirty_blockindex.insert(pindex);
     }
 
     // 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 any of the prune locks bestblocks.
                 // Pruning is height-based.
                 int last_prune{m_chain.Height()};
                 // prune lock that actually was the limiting factor, only used
                 // for logging
                 std::optional<std::string> limiting_lock;
-                ForEachBlockFilterIndex([&](BlockFilterIndex &index) {
-                    last_prune = std::max(
-                        1, std::min(last_prune,
-                                    index.GetSummary().best_block_height));
-                });
 
                 for (const auto &prune_lock : m_blockman.m_prune_locks) {
                     if (prune_lock.second.height_first ==
                         std::numeric_limits<int>::max()) {
                         continue;
                     }
                     // Remove the buffer and one additional block here to get
                     // actual height that is outside of the buffer
                     const int lock_height{prune_lock.second.height_first -
                                           PRUNE_LOCK_BUFFER - 1};
                     last_prune = std::max(1, std::min(last_prune, lock_height));
                     if (last_prune == lock_height) {
                         limiting_lock = prune_lock.first;
                     }
                 }
 
                 if (limiting_lock) {
                     LogPrint(BCLog::PRUNE, "%s limited pruning to height %d\n",
                              limiting_lock.value(), last_prune);
                 }
 
                 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);
     assert(pindexDelete->pprev);
 
     // 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);
 
     {
         // Prune locks that began at or after the tip should be moved backward
         // so they get a chance to reorg
         const int max_height_first{pindexDelete->nHeight - 1};
         for (auto &prune_lock : m_blockman.m_prune_locks) {
             if (prune_lock.second.height_first <= max_height_first) {
                 continue;
             }
 
             prune_lock.second.height_first = max_height_first;
             LogPrint(BCLog::PRUNE, "%s prune lock moved back to %d\n",
                      prune_lock.first, max_height_first);
         }
     }
 
     // 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,
     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 =
             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);
 
     // 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,
     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(), 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,
     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, 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, 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();
         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, 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);
         // nRewind indicates where to resume scanning in case something goes
         // wrong, such as a block fails to deserialize.
         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(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.
                 // (this happens at the end of every blk.dat file)
                 break;
             }
 
             try {
                 // read block header
                 const uint64_t nBlockPos{blkdat.GetPos()};
                 if (dbp) {
                     dbp->nPos = nBlockPos;
                 }
                 blkdat.SetLimit(nBlockPos + nSize);
                 CBlockHeader header;
                 blkdat >> header;
                 const BlockHash hash{header.GetHash()};
                 // Skip the rest of this block (this may read from disk
                 // into memory); position to the marker before the next block,
                 // but it's still possible to rewind to the start of the
                 // current block (without a disk read).
                 nRewind = nBlockPos + nSize;
                 blkdat.SkipTo(nRewind);
 
                 // needs to remain available after the cs_main lock is released
                 // to avoid duplicate reads from disk
                 std::shared_ptr<CBlock> pblock{};
 
                 {
                     LOCK(cs_main);
                     // detect out of order blocks, and store them for later
                     if (hash != params.GetConsensus().hashGenesisBlock &&
                         !m_blockman.LookupBlockIndex(header.hashPrevBlock)) {
                         LogPrint(
                             BCLog::REINDEX,
                             "%s: Out of order block %s, parent %s not known\n",
                             __func__, hash.ToString(),
                             header.hashPrevBlock.ToString());
                         if (dbp && blocks_with_unknown_parent) {
                             blocks_with_unknown_parent->emplace(
                                 header.hashPrevBlock, *dbp);
                         }
                         continue;
                     }
 
                     // process in case the block isn't known yet
                     const CBlockIndex *pindex =
                         m_blockman.LookupBlockIndex(hash);
                     if (!pindex || !pindex->nStatus.hasData()) {
                         // This block can be processed immediately; rewind to
                         // its start, read and deserialize it.
                         blkdat.SetPos(nBlockPos);
                         pblock = std::make_shared<CBlock>();
                         blkdat >> *pblock;
                         nRewind = blkdat.GetPos();
 
                         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 will be 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()));
 
         auto rename_result = m_snapshot_chainstate->InvalidateCoinsDBOnDisk();
         if (!rename_result) {
             user_error = strprintf(Untranslated("%s\n%s"), user_error,
                                    util::ErrorString(rename_result));
         }
 
         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, node::BlockManager::Options blockman_options)
     : m_options{Flatten(std::move(options))}, m_blockman{std::move(
                                                   blockman_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;
 }
 
 util::Result<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());
         return util::Error{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)};
     }
     return {};
 }
 
 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/test/lint/lint-circular-dependencies.sh b/test/lint/lint-circular-dependencies.sh
index 2f4f1bcc4..beaa006a4 100755
--- a/test/lint/lint-circular-dependencies.sh
+++ b/test/lint/lint-circular-dependencies.sh
@@ -1,83 +1,81 @@
 #!/usr/bin/env bash
 #
 # Copyright (c) 2018 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 #
 # Check for circular dependencies
 
 export LC_ALL=C
 
 set -euo pipefail
 
 : "${TOPLEVEL:=$(git rev-parse --show-toplevel)}"
 
 EXPECTED_CIRCULAR_DEPENDENCIES=(
     "node/blockstorage -> validation -> node/blockstorage"
     "node/utxo_snapshot -> validation -> node/utxo_snapshot"
-    "index/blockfilterindex -> node/blockstorage -> validation -> index/blockfilterindex"
-    "index/base -> validation -> index/blockfilterindex -> index/base"
     "index/coinstatsindex -> node/coinstats -> index/coinstatsindex"
     "qt/addresstablemodel -> qt/walletmodel -> qt/addresstablemodel"
     "qt/bitcoingui -> qt/walletframe -> qt/bitcoingui"
     "qt/recentrequeststablemodel -> qt/walletmodel -> qt/recentrequeststablemodel"
     "qt/transactiontablemodel -> qt/walletmodel -> qt/transactiontablemodel"
     "wallet/fees -> wallet/wallet -> wallet/fees"
     "wallet/rpcwallet -> wallet/wallet -> wallet/rpcwallet"
     "wallet/wallet -> wallet/walletdb -> wallet/wallet"
     "avalanche/processor -> validation -> avalanche/processor"
     "avalanche/processor -> policy/block/stakingrewards -> avalanche/processor"
     "chainparams -> protocol -> chainparams"
     "chainparamsbase -> util/system -> chainparamsbase"
     "script/scriptcache -> validation -> script/scriptcache"
     "seeder/bitcoin -> seeder/db -> seeder/bitcoin"
     "chainparams -> protocol -> config -> chainparams"
     "avalanche/peermanager -> avalanche/proofpool -> avalanche/peermanager"
     "node/coinstats -> validation -> node/coinstats"
     "kernel/mempool_persist -> validation -> kernel/mempool_persist"
     "kernel/disconnected_transactions -> validation -> kernel/disconnected_transactions"
 )
 
 EXIT_CODE=0
 
 CIRCULAR_DEPENDENCIES=()
 
 pushd "${TOPLEVEL}"
 
 IFS=$'\n'
 for CIRC in $(cd src && ../contrib/devtools/circular-dependencies.py {*,*/*,*/*/*}.{h,cpp} | sed -e 's/^Circular dependency: //'); do
     CIRCULAR_DEPENDENCIES+=("$CIRC")
     IS_EXPECTED_CIRC=0
     for EXPECTED_CIRC in "${EXPECTED_CIRCULAR_DEPENDENCIES[@]}"; do
         if [[ "${CIRC}" == "${EXPECTED_CIRC}" ]]; then
             IS_EXPECTED_CIRC=1
             break
         fi
     done
     if [[ ${IS_EXPECTED_CIRC} == 0 ]]; then
         echo "A new circular dependency in the form of \"${CIRC}\" appears to have been introduced."
         echo
         EXIT_CODE=1
     fi
 done
 
 for EXPECTED_CIRC in "${EXPECTED_CIRCULAR_DEPENDENCIES[@]}"; do
     IS_PRESENT_EXPECTED_CIRC=0
     for CIRC in "${CIRCULAR_DEPENDENCIES[@]}"; do
         if [[ "${CIRC}" == "${EXPECTED_CIRC}" ]]; then
             IS_PRESENT_EXPECTED_CIRC=1
             break
         fi
     done
     if [[ ${IS_PRESENT_EXPECTED_CIRC} == 0 ]]; then
         echo "Good job! The circular dependency \"${EXPECTED_CIRC}\" is no longer present."
         echo "Please remove it from EXPECTED_CIRCULAR_DEPENDENCIES in $0"
         echo "to make sure this circular dependency is not accidentally reintroduced."
         echo
         EXIT_CODE=1
     fi
 done
 
 popd
 
 exit ${EXIT_CODE}