Function backupDb

app/redis-6.2.6/src/db.c:467–493

Store a backup of the database for later use, and put an empty one * instead of it. */

/* Store a backup of the database for later use, and put an empty one
 * instead of it. */
dbBackup *backupDb(void) {
    dbBackup *backup = zmalloc(sizeof(dbBackup));

    /* Backup main DBs. */
    backup->dbarray = zmalloc(sizeof(redisDb)*server.dbnum);
    for (int i=0; i<server.dbnum; i++) {
        backup->dbarray[i] = server.db[i];
        server.db[i].dict = dictCreate(&dbDictType,NULL);
        server.db[i].expires = dictCreate(&dbExpiresDictType,NULL);
    }

    /* Backup cluster slots to keys map if enable cluster. */
    if (server.cluster_enabled) {
        backup->slots_to_keys = server.cluster->slots_to_keys;
        memcpy(backup->slots_keys_count, server.cluster->slots_keys_count,
            sizeof(server.cluster->slots_keys_count));
        server.cluster->slots_to_keys = raxNew();
        memset(server.cluster->slots_keys_count, 0,
            sizeof(server.cluster->slots_keys_count));
    }

    moduleFireServerEvent(REDISMODULE_EVENT_REPL_BACKUP,
                          REDISMODULE_SUBEVENT_REPL_BACKUP_CREATE,
                          NULL);

    return backup;
}

/* Discard a previously created backup, this can be slow (similar to FLUSHALL)
 * Arguments are similar to the ones of emptyDb, see EMPTYDB_ flags. */