Method Rewrite

src/wallet/db.cpp:575–661

}

bool BerkeleyBatch::Rewrite(BerkeleyDatabase& database, const char* pszSkip)
{
    if (database.IsDummy()) {
        return true;
    }
    BerkeleyEnvironment *env = database.env;
    const std::string& strFile = database.strFile;
    while (true) {
        {
            LOCK(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("BerkeleyBatch::Rewrite: Rewriting %s...\n", strFile);
                std::string strFileRes = strFile + ".rewrite";
                { // surround usage of db with extra {}
                    BerkeleyBatch db(database, "r");
                    std::unique_ptr<Db> pdbCopy = MakeUnique<Db>(env->dbenv.get(), 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("BerkeleyBatch::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;
                            } else 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());