diff --git a/src/wallet/db.cpp b/src/wallet/db.cpp
index 035b72ee5..26573a407 100644
--- a/src/wallet/db.cpp
+++ b/src/wallet/db.cpp
@@ -1,744 +1,741 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2016 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 "db.h"
 
 #include "addrman.h"
 #include "fs.h"
 #include "hash.h"
 #include "protocol.h"
 #include "util.h"
 #include "utilstrencodings.h"
 
 #include <boost/thread.hpp>
 #include <boost/version.hpp>
 
 #include <cstdint>
 
 #ifndef WIN32
 #include <sys/stat.h>
 #endif
 
 //
 // CDB
 //
 
 CDBEnv bitdb;
 
 void CDBEnv::EnvShutdown() {
     if (!fDbEnvInit) {
         return;
     }
 
     fDbEnvInit = false;
     int ret = dbenv->close(0);
     if (ret != 0) {
         LogPrintf("CDBEnv::EnvShutdown: Error %d shutting down database "
                   "environment: %s\n",
                   ret, DbEnv::strerror(ret));
     }
 
     if (!fMockDb) {
         DbEnv(uint32_t(0)).remove(strPath.c_str(), 0);
     }
 }
 
 void CDBEnv::Reset() {
     delete dbenv;
     dbenv = new DbEnv(DB_CXX_NO_EXCEPTIONS);
     fDbEnvInit = false;
     fMockDb = false;
 }
 
 CDBEnv::CDBEnv() : dbenv(nullptr) {
     Reset();
 }
 
 CDBEnv::~CDBEnv() {
     EnvShutdown();
     delete dbenv;
     dbenv = nullptr;
 }
 
 void CDBEnv::Close() {
     EnvShutdown();
 }
 
 bool CDBEnv::Open(const fs::path &pathIn) {
     if (fDbEnvInit) {
         return true;
     }
 
     boost::this_thread::interruption_point();
 
     strPath = pathIn.string();
     fs::path pathLogDir = pathIn / "database";
     TryCreateDirectories(pathLogDir);
     fs::path pathErrorFile = pathIn / "db.log";
     LogPrintf("CDBEnv::Open: LogDir=%s ErrorFile=%s\n", pathLogDir.string(),
               pathErrorFile.string());
 
     unsigned int nEnvFlags = 0;
     if (gArgs.GetBoolArg("-privdb", DEFAULT_WALLET_PRIVDB)) {
         nEnvFlags |= DB_PRIVATE;
     }
 
     dbenv->set_lg_dir(pathLogDir.string().c_str());
     // 1 MiB should be enough for just the wallet
     dbenv->set_cachesize(0, 0x100000, 1);
     dbenv->set_lg_bsize(0x10000);
     dbenv->set_lg_max(1048576);
     dbenv->set_lk_max_locks(40000);
     dbenv->set_lk_max_objects(40000);
     /// debug
     dbenv->set_errfile(fsbridge::fopen(pathErrorFile, "a"));
     dbenv->set_flags(DB_AUTO_COMMIT, 1);
     dbenv->set_flags(DB_TXN_WRITE_NOSYNC, 1);
     dbenv->log_set_config(DB_LOG_AUTO_REMOVE, 1);
     int ret =
         dbenv->open(strPath.c_str(),
                     DB_CREATE | DB_INIT_LOCK | DB_INIT_LOG | DB_INIT_MPOOL |
                         DB_INIT_TXN | DB_THREAD | DB_RECOVER | nEnvFlags,
                     S_IRUSR | S_IWUSR);
     if (ret != 0) {
         return error(
             "CDBEnv::Open: Error %d opening database environment: %s\n", ret,
             DbEnv::strerror(ret));
     }
 
     fDbEnvInit = true;
     fMockDb = false;
     return true;
 }
 
 void CDBEnv::MakeMock() {
     if (fDbEnvInit) {
         throw std::runtime_error("CDBEnv::MakeMock: Already initialized");
     }
 
     boost::this_thread::interruption_point();
 
     LogPrint(BCLog::DB, "CDBEnv::MakeMock\n");
 
     dbenv->set_cachesize(1, 0, 1);
     dbenv->set_lg_bsize(10485760 * 4);
     dbenv->set_lg_max(10485760);
     dbenv->set_lk_max_locks(10000);
     dbenv->set_lk_max_objects(10000);
     dbenv->set_flags(DB_AUTO_COMMIT, 1);
     dbenv->log_set_config(DB_LOG_IN_MEMORY, 1);
     int ret =
         dbenv->open(nullptr,
                     DB_CREATE | DB_INIT_LOCK | DB_INIT_LOG | DB_INIT_MPOOL |
                         DB_INIT_TXN | DB_THREAD | DB_PRIVATE,
                     S_IRUSR | S_IWUSR);
     if (ret > 0) {
         throw std::runtime_error(strprintf(
             "CDBEnv::MakeMock: Error %d opening database environment.", ret));
     }
 
     fDbEnvInit = true;
     fMockDb = true;
 }
 
 CDBEnv::VerifyResult CDBEnv::Verify(const std::string &strFile,
                                     recoverFunc_type recoverFunc,
                                     std::string &out_backup_filename) {
     LOCK(cs_db);
     assert(mapFileUseCount.count(strFile) == 0);
 
     Db db(dbenv, 0);
     int result = db.verify(strFile.c_str(), nullptr, nullptr, 0);
     if (result == 0) {
         return VERIFY_OK;
     } else if (recoverFunc == nullptr) {
         return RECOVER_FAIL;
     }
 
     // Try to recover:
     bool fRecovered = (*recoverFunc)(strFile, out_backup_filename);
     return (fRecovered ? RECOVER_OK : RECOVER_FAIL);
 }
 
 bool CDB::Recover(const std::string &filename, void *callbackDataIn,
                   bool (*recoverKVcallback)(void *callbackData,
                                             CDataStream ssKey,
                                             CDataStream ssValue),
                   std::string &newFilename) {
     // Recovery procedure:
     // Move wallet file to walletfilename.timestamp.bak
     // Call Salvage with fAggressive=true to get as much data as possible.
     // Rewrite salvaged data to fresh wallet file.
     // Set -rescan so any missing transactions will be found.
     int64_t now = GetTime();
     newFilename = strprintf("%s.%d.bak", filename, now);
 
     int result = bitdb.dbenv->dbrename(nullptr, filename.c_str(), nullptr,
                                        newFilename.c_str(), DB_AUTO_COMMIT);
     if (result == 0) {
         LogPrintf("Renamed %s to %s\n", filename, newFilename);
     } else {
         LogPrintf("Failed to rename %s to %s\n", filename, newFilename);
         return false;
     }
 
     std::vector<CDBEnv::KeyValPair> salvagedData;
     bool fSuccess = bitdb.Salvage(newFilename, true, salvagedData);
     if (salvagedData.empty()) {
         LogPrintf("Salvage(aggressive) found no records in %s.\n", newFilename);
         return false;
     }
     LogPrintf("Salvage(aggressive) found %u records\n", salvagedData.size());
 
     std::unique_ptr<Db> pdbCopy(new Db(bitdb.dbenv, 0));
     int ret = pdbCopy->open(nullptr,          // Txn pointer
                             filename.c_str(), // Filename
                             "main",           // Logical db name
                             DB_BTREE,         // Database type
                             DB_CREATE,        // Flags
                             0);
     if (ret > 0) {
         LogPrintf("Cannot create database file %s\n", filename);
         return false;
     }
 
     DbTxn *ptxn = bitdb.TxnBegin();
     for (CDBEnv::KeyValPair &row : salvagedData) {
         if (recoverKVcallback) {
             CDataStream ssKey(row.first, SER_DISK, CLIENT_VERSION);
             CDataStream ssValue(row.second, SER_DISK, CLIENT_VERSION);
             std::string strType, strErr;
             if (!(*recoverKVcallback)(callbackDataIn, ssKey, ssValue)) {
                 continue;
             }
         }
         Dbt datKey(&row.first[0], row.first.size());
         Dbt datValue(&row.second[0], row.second.size());
         int ret2 = pdbCopy->put(ptxn, &datKey, &datValue, DB_NOOVERWRITE);
         if (ret2 > 0) {
             fSuccess = false;
         }
     }
     ptxn->commit(0);
     pdbCopy->close(0);
 
     return fSuccess;
 }
 
 bool CDB::VerifyEnvironment(const std::string &walletFile,
                             const fs::path &dataDir, std::string &errorStr) {
     LogPrintf("Using BerkeleyDB version %s\n", DbEnv::version(0, 0, 0));
     LogPrintf("Using wallet %s\n", walletFile);
 
     // Wallet file must be a plain filename without a directory
     if (walletFile != fs::basename(walletFile) + fs::extension(walletFile)) {
         errorStr = strprintf(_("Wallet %s resides outside data directory %s"),
                              walletFile, dataDir.string());
         return false;
     }
 
     if (!bitdb.Open(dataDir)) {
         // try moving the database env out of the way
         fs::path pathDatabase = dataDir / "database";
         fs::path pathDatabaseBak =
             dataDir / strprintf("database.%d.bak", GetTime());
         try {
             fs::rename(pathDatabase, pathDatabaseBak);
             LogPrintf("Moved old %s to %s. Retrying.\n", pathDatabase.string(),
                       pathDatabaseBak.string());
         } catch (const fs::filesystem_error &) {
             // failure is ok (well, not really, but it's not worse than what we
             // started with)
         }
 
         // try again
         if (!bitdb.Open(dataDir)) {
             // if it still fails, it probably means we can't even create the
             // database env
             errorStr = strprintf(
                 _("Error initializing wallet database environment %s!"),
                 GetDataDir());
             return false;
         }
     }
     return true;
 }
 
 bool CDB::VerifyDatabaseFile(const std::string &walletFile,
                              const fs::path &dataDir, std::string &warningStr,
                              std::string &errorStr,
                              CDBEnv::recoverFunc_type recoverFunc) {
     if (fs::exists(dataDir / walletFile)) {
         std::string backup_filename;
         CDBEnv::VerifyResult r =
             bitdb.Verify(walletFile, recoverFunc, backup_filename);
         if (r == CDBEnv::RECOVER_OK) {
             warningStr = strprintf(
                 _("Warning: Wallet file corrupt, data salvaged!"
                   " Original %s saved as %s in %s; if"
                   " your balance or transactions are incorrect you should"
                   " restore from a backup."),
                 walletFile, backup_filename, dataDir);
         }
         if (r == CDBEnv::RECOVER_FAIL) {
             errorStr = strprintf(_("%s corrupt, salvage failed"), walletFile);
             return false;
         }
     }
     // also return true if files does not exists
     return true;
 }
 
 /* End of headers, beginning of key/value data */
 static const char *HEADER_END = "HEADER=END";
 /* End of key/value data */
 static const char *DATA_END = "DATA=END";
 
 bool CDBEnv::Salvage(const std::string &strFile, bool fAggressive,
                      std::vector<CDBEnv::KeyValPair> &vResult) {
     LOCK(cs_db);
     assert(mapFileUseCount.count(strFile) == 0);
 
     u_int32_t flags = DB_SALVAGE;
     if (fAggressive) {
         flags |= DB_AGGRESSIVE;
     }
 
     std::stringstream strDump;
 
     Db db(dbenv, 0);
     int result = db.verify(strFile.c_str(), nullptr, &strDump, flags);
     if (result == DB_VERIFY_BAD) {
         LogPrintf("CDBEnv::Salvage: Database salvage found errors, all data "
                   "may not be recoverable.\n");
         if (!fAggressive) {
             LogPrintf("CDBEnv::Salvage: Rerun with aggressive mode to ignore "
                       "errors and continue.\n");
             return false;
         }
     }
     if (result != 0 && result != DB_VERIFY_BAD) {
         LogPrintf("CDBEnv::Salvage: Database salvage failed with result %d.\n",
                   result);
         return false;
     }
 
     // Format of bdb dump is ascii lines:
     // header lines...
     // HEADER=END
     //  hexadecimal key
     //  hexadecimal value
     //  ... repeated
     // DATA=END
 
     std::string strLine;
     while (!strDump.eof() && strLine != HEADER_END) {
         // Skip past header
         getline(strDump, strLine);
     }
 
     std::string keyHex, valueHex;
     while (!strDump.eof() && keyHex != DATA_END) {
         getline(strDump, keyHex);
         if (keyHex != DATA_END) {
             if (strDump.eof()) {
                 break;
             }
             getline(strDump, valueHex);
             if (valueHex == DATA_END) {
                 LogPrintf("CDBEnv::Salvage: WARNING: Number of keys in data "
                           "does not match number of values.\n");
                 break;
             }
             vResult.push_back(make_pair(ParseHex(keyHex), ParseHex(valueHex)));
         }
     }
 
     if (keyHex != DATA_END) {
         LogPrintf("CDBEnv::Salvage: WARNING: Unexpected end of file while "
                   "reading salvage output.\n");
         return false;
     }
 
     return (result == 0);
 }
 
 void CDBEnv::CheckpointLSN(const std::string &strFile) {
     dbenv->txn_checkpoint(0, 0, 0);
     if (fMockDb) {
         return;
     }
     dbenv->lsn_reset(strFile.c_str(), 0);
 }
 
 CDB::CDB(CWalletDBWrapper &dbw, const char *pszMode, bool fFlushOnCloseIn)
     : pdb(nullptr), activeTxn(nullptr) {
     int ret;
     fReadOnly = (!strchr(pszMode, '+') && !strchr(pszMode, 'w'));
     fFlushOnClose = fFlushOnCloseIn;
     env = dbw.env;
     if (dbw.IsDummy()) {
         return;
     }
 
     const std::string &strFilename = dbw.strFile;
 
     bool fCreate = strchr(pszMode, 'c') != nullptr;
     unsigned int nFlags = DB_THREAD;
     if (fCreate) {
         nFlags |= DB_CREATE;
     }
 
     {
         LOCK(env->cs_db);
         if (!env->Open(GetDataDir())) {
             throw std::runtime_error(
                 "CDB: Failed to open database environment.");
         }
 
-        strFile = strFilename;
-        ++env->mapFileUseCount[strFile];
-        pdb = env->mapDb[strFile];
+        pdb = env->mapDb[strFilename];
         if (pdb == nullptr) {
-            pdb = new Db(env->dbenv, 0);
+            std::unique_ptr<Db> pdb_temp(new Db(env->dbenv, 0));
 
             bool fMockDb = env->IsMock();
             if (fMockDb) {
-                DbMpoolFile *mpf = pdb->get_mpf();
+                DbMpoolFile *mpf = pdb_temp->get_mpf();
                 ret = mpf->set_flags(DB_MPOOL_NOFILE, 1);
                 if (ret != 0) {
                     throw std::runtime_error(
                         strprintf("CDB: Failed to configure for no temp file "
                                   "backing for database %s",
-                                  strFile));
+                                  strFilename));
                 }
             }
 
-            ret =
-                pdb->open(nullptr,                             // Txn pointer
-                          fMockDb ? nullptr : strFile.c_str(), // Filename
-                          fMockDb ? strFile.c_str() : "main", // Logical db name
-                          DB_BTREE,                           // Database type
-                          nFlags,                             // Flags
-                          0);
+            ret = pdb_temp->open(
+                nullptr,                                 // Txn pointer
+                fMockDb ? nullptr : strFilename.c_str(), // Filename
+                fMockDb ? strFilename.c_str() : "main",  // Logical db name
+                DB_BTREE,                                // Database type
+                nFlags,                                  // Flags
+                0);
 
             if (ret != 0) {
-                delete pdb;
-                pdb = nullptr;
-                --env->mapFileUseCount[strFile];
-                strFile = "";
                 throw std::runtime_error(strprintf(
                     "CDB: Error %d, can't open database %s", ret, strFilename));
             }
 
+            pdb = pdb_temp.release();
+            env->mapDb[strFilename] = pdb;
+
             if (fCreate && !Exists(std::string("version"))) {
                 bool fTmp = fReadOnly;
                 fReadOnly = false;
                 WriteVersion(CLIENT_VERSION);
                 fReadOnly = fTmp;
             }
-
-            env->mapDb[strFile] = pdb;
         }
+        ++env->mapFileUseCount[strFilename];
+        strFile = strFilename;
     }
 }
 
 void CDB::Flush() {
     if (activeTxn) {
         return;
     }
 
     // Flush database activity from memory pool to disk log
     unsigned int nMinutes = 0;
     if (fReadOnly) {
         nMinutes = 1;
     }
 
     env->dbenv->txn_checkpoint(
         nMinutes ? gArgs.GetArg("-dblogsize", DEFAULT_WALLET_DBLOGSIZE) * 1024
                  : 0,
         nMinutes, 0);
 }
 
 void CWalletDBWrapper::IncrementUpdateCounter() {
     ++nUpdateCounter;
 }
 
 void CDB::Close() {
     if (!pdb) {
         return;
     }
     if (activeTxn) {
         activeTxn->abort();
     }
     activeTxn = nullptr;
     pdb = nullptr;
 
     if (fFlushOnClose) {
         Flush();
     }
 
     LOCK(env->cs_db);
     --env->mapFileUseCount[strFile];
 }
 
 void CDBEnv::CloseDb(const std::string &strFile) {
     LOCK(cs_db);
     if (mapDb[strFile] != nullptr) {
         // Close the database handle
         Db *pdb = mapDb[strFile];
         pdb->close(0);
         delete pdb;
         mapDb[strFile] = nullptr;
     }
 }
 
 bool CDB::Rewrite(CWalletDBWrapper &dbw, const char *pszSkip) {
     if (dbw.IsDummy()) {
         return true;
     }
     CDBEnv *env = dbw.env;
     const std::string &strFile = dbw.strFile;
     while (true) {
         {
             LOCK(env->cs_db);
             if (!env->mapFileUseCount.count(strFile) ||
                 env->mapFileUseCount[strFile] == 0) {
                 // Flush log data to the dat file
                 env->CloseDb(strFile);
                 env->CheckpointLSN(strFile);
                 env->mapFileUseCount.erase(strFile);
 
                 bool fSuccess = true;
                 LogPrintf("CDB::Rewrite: Rewriting %s...\n", strFile);
                 std::string strFileRes = strFile + ".rewrite";
                 {
                     // surround usage of db with extra {}
                     CDB db(dbw, "r");
                     Db *pdbCopy = new Db(env->dbenv, 0);
 
                     int ret = pdbCopy->open(nullptr,            // Txn pointer
                                             strFileRes.c_str(), // Filename
                                             "main",    // Logical db name
                                             DB_BTREE,  // Database type
                                             DB_CREATE, // Flags
                                             0);
                     if (ret > 0) {
                         LogPrintf(
                             "CDB::Rewrite: Can't create database file %s\n",
                             strFileRes);
                         fSuccess = false;
                     }
 
                     Dbc *pcursor = db.GetCursor();
                     if (pcursor)
                         while (fSuccess) {
                             CDataStream ssKey(SER_DISK, CLIENT_VERSION);
                             CDataStream ssValue(SER_DISK, CLIENT_VERSION);
                             int ret1 = db.ReadAtCursor(pcursor, ssKey, ssValue);
                             if (ret1 == DB_NOTFOUND) {
                                 pcursor->close();
                                 break;
                             }
                             if (ret1 != 0) {
                                 pcursor->close();
                                 fSuccess = false;
                                 break;
                             }
                             if (pszSkip &&
                                 strncmp(ssKey.data(), pszSkip,
                                         std::min(ssKey.size(),
                                                  strlen(pszSkip))) == 0) {
                                 continue;
                             }
                             if (strncmp(ssKey.data(), "\x07version", 8) == 0) {
                                 // Update version:
                                 ssValue.clear();
                                 ssValue << CLIENT_VERSION;
                             }
                             Dbt datKey(ssKey.data(), ssKey.size());
                             Dbt datValue(ssValue.data(), ssValue.size());
                             int ret2 = pdbCopy->put(nullptr, &datKey, &datValue,
                                                     DB_NOOVERWRITE);
                             if (ret2 > 0) {
                                 fSuccess = false;
                             }
                         }
                     if (fSuccess) {
                         db.Close();
                         env->CloseDb(strFile);
                         if (pdbCopy->close(0)) {
                             fSuccess = false;
                         }
                         delete pdbCopy;
                     }
                 }
                 if (fSuccess) {
                     Db dbA(env->dbenv, 0);
                     if (dbA.remove(strFile.c_str(), nullptr, 0)) {
                         fSuccess = false;
                     }
                     Db dbB(env->dbenv, 0);
                     if (dbB.rename(strFileRes.c_str(), nullptr, strFile.c_str(),
                                    0)) {
                         fSuccess = false;
                     }
                 }
                 if (!fSuccess) {
                     LogPrintf(
                         "CDB::Rewrite: Failed to rewrite database file %s\n",
                         strFileRes);
                 }
                 return fSuccess;
             }
         }
         MilliSleep(100);
     }
     return false;
 }
 
 void CDBEnv::Flush(bool fShutdown) {
     int64_t nStart = GetTimeMillis();
     // Flush log data to the actual data file on all files that are not in use
     LogPrint(BCLog::DB, "CDBEnv::Flush: Flush(%s)%s\n",
              fShutdown ? "true" : "false",
              fDbEnvInit ? "" : " database not started");
     if (!fDbEnvInit) {
         return;
     }
     {
         LOCK(cs_db);
         std::map<std::string, int>::iterator mi = mapFileUseCount.begin();
         while (mi != mapFileUseCount.end()) {
             std::string strFile = (*mi).first;
             int nRefCount = (*mi).second;
             LogPrint(BCLog::DB,
                      "CDBEnv::Flush: Flushing %s (refcount = %d)...\n", strFile,
                      nRefCount);
             if (nRefCount == 0) {
                 // Move log data to the dat file
                 CloseDb(strFile);
                 LogPrint(BCLog::DB, "CDBEnv::Flush: %s checkpoint\n", strFile);
                 dbenv->txn_checkpoint(0, 0, 0);
                 LogPrint(BCLog::DB, "CDBEnv::Flush: %s detach\n", strFile);
                 if (!fMockDb) {
                     dbenv->lsn_reset(strFile.c_str(), 0);
                 }
                 LogPrint(BCLog::DB, "CDBEnv::Flush: %s closed\n", strFile);
                 mapFileUseCount.erase(mi++);
             } else {
                 mi++;
             }
         }
         LogPrint(BCLog::DB, "CDBEnv::Flush: Flush(%s)%s took %15dms\n",
                  fShutdown ? "true" : "false",
                  fDbEnvInit ? "" : " database not started",
                  GetTimeMillis() - nStart);
         if (fShutdown) {
             char **listp;
             if (mapFileUseCount.empty()) {
                 dbenv->log_archive(&listp, DB_ARCH_REMOVE);
                 Close();
                 if (!fMockDb) {
                     fs::remove_all(fs::path(strPath) / "database");
                 }
             }
         }
     }
 }
 
 bool CDB::PeriodicFlush(CWalletDBWrapper &dbw) {
     if (dbw.IsDummy()) {
         return true;
     }
     bool ret = false;
     CDBEnv *env = dbw.env;
     const std::string &strFile = dbw.strFile;
     TRY_LOCK(bitdb.cs_db, lockDb);
     if (lockDb) {
         // Don't do this if any databases are in use
         int nRefCount = 0;
         std::map<std::string, int>::iterator mit = env->mapFileUseCount.begin();
         while (mit != env->mapFileUseCount.end()) {
             nRefCount += (*mit).second;
             mit++;
         }
 
         if (nRefCount == 0) {
             boost::this_thread::interruption_point();
             std::map<std::string, int>::iterator mi =
                 env->mapFileUseCount.find(strFile);
             if (mi != env->mapFileUseCount.end()) {
                 LogPrint(BCLog::DB, "Flushing %s\n", strFile);
                 int64_t nStart = GetTimeMillis();
 
                 // Flush wallet file so it's self contained
                 env->CloseDb(strFile);
                 env->CheckpointLSN(strFile);
 
                 env->mapFileUseCount.erase(mi++);
                 LogPrint(BCLog::DB, "Flushed %s %dms\n", strFile,
                          GetTimeMillis() - nStart);
                 ret = true;
             }
         }
     }
 
     return ret;
 }
 
 bool CWalletDBWrapper::Rewrite(const char *pszSkip) {
     return CDB::Rewrite(*this, pszSkip);
 }
 
 bool CWalletDBWrapper::Backup(const std::string &strDest) {
     if (IsDummy()) {
         return false;
     }
     while (true) {
         {
             LOCK(env->cs_db);
             if (!env->mapFileUseCount.count(strFile) ||
                 env->mapFileUseCount[strFile] == 0) {
                 // Flush log data to the dat file
                 env->CloseDb(strFile);
                 env->CheckpointLSN(strFile);
                 env->mapFileUseCount.erase(strFile);
 
                 // Copy wallet file.
                 fs::path pathSrc = GetDataDir() / strFile;
                 fs::path pathDest(strDest);
                 if (fs::is_directory(pathDest)) {
                     pathDest /= strFile;
                 }
 
                 try {
                     if (fs::equivalent(pathSrc, pathDest)) {
                         LogPrintf("cannot backup to wallet source file %s\n",
                                   pathDest.string());
                         return false;
                     }
 
                     fs::copy_file(pathSrc, pathDest,
                                   fs::copy_option::overwrite_if_exists);
                     LogPrintf("copied %s to %s\n", strFile, pathDest.string());
                     return true;
                 } catch (const fs::filesystem_error &e) {
                     LogPrintf("error copying %s to %s - %s\n", strFile,
                               pathDest.string(), e.what());
                     return false;
                 }
             }
         }
         MilliSleep(100);
     }
     return false;
 }
 
 void CWalletDBWrapper::Flush(bool shutdown) {
     if (!IsDummy()) {
         env->Flush(shutdown);
     }
 }