Function rememberSlaveKeyWithExpire

src/expire.cpp:667–695

Track keys that received an EXPIRE or similar command in the context * of a writable replica. */

/* Track keys that received an EXPIRE or similar command in the context
 * of a writable replica. */
void rememberSlaveKeyWithExpire(redisDb *db, robj *key) {
    if (slaveKeysWithExpire == NULL) {
        static dictType dt = {
            dictSdsHash,                /* hash function */
            NULL,                       /* key dup */
            NULL,                       /* val dup */
            dictSdsKeyCompare,          /* key compare */
            dictSdsDestructor,          /* key destructor */
            NULL,                       /* val destructor */
            NULL                        /* allow to expand */
        };
        slaveKeysWithExpire = dictCreate(&dt,NULL);
    }
    if (db->id > 63) return;

    dictEntry *de = dictAddOrFind(slaveKeysWithExpire,ptrFromObj(key));
    /* If the entry was just created, set it to a copy of the SDS string
     * representing the key: we don't want to need to take those keys
     * in sync with the main DB. The keys will be removed by expireSlaveKeys()
     * as it scans to find keys to remove. */
    if (de->key == ptrFromObj(key)) {
        de->key = sdsdup(szFromObj(key));
        dictSetUnsignedIntegerVal(de,0);
    }

    uint64_t dbids = dictGetUnsignedIntegerVal(de);
    dbids |= (uint64_t)1 << db->id;
    dictSetUnsignedIntegerVal(de,dbids);
}

/* Return the number of keys we are tracking. */
size_t getSlaveKeyWithExpireCount(void) {