Function trackingRememberKeys

src/tracking.cpp:217–248

This function is called after the execution of a readonly command in the * case the client 'c' has keys tracking enabled and the tracking is not * in BCAST mode. It will populate the tracking invalidation table according * to the keys the user fetched, so that Redis will know what are the clients * that should receive an invalidation message with certain groups of keys * are modified. */

 * that should receive an invalidation message with certain groups of keys
 * are modified. */
void trackingRememberKeys(client *c) {
    /* Return if we are in optin/out mode and the right CACHING command
     * was/wasn't given in order to modify the default behavior. */
    uint64_t optin = c->flags & CLIENT_TRACKING_OPTIN;
    uint64_t optout = c->flags & CLIENT_TRACKING_OPTOUT;
    uint64_t caching_given = c->flags & CLIENT_TRACKING_CACHING;
    if ((optin && !caching_given) || (optout && caching_given)) return;

    getKeysResult result = GETKEYS_RESULT_INIT;
    int numkeys = getKeysFromCommand(c->cmd,c->argv,c->argc,&result);
    if (!numkeys) {
        getKeysFreeResult(&result);
        return;
    }

    int *keys = result.keys;

    for(int j = 0; j < numkeys; j++) {
        int idx = keys[j];
        sds sdskey = szFromObj(c->argv[idx]);
        rax *ids = (rax*)raxFind(TrackingTable,(unsigned char*)sdskey,sdslen(sdskey));
        if (ids == raxNotFound) {
            ids = raxNew();
            int inserted = raxTryInsert(TrackingTable,(unsigned char*)sdskey,
                                        sdslen(sdskey),ids, NULL);
            serverAssert(inserted == 1);
        }
        if (raxTryInsert(ids,(unsigned char*)&c->id,sizeof(c->id),NULL,NULL))
            TrackingTableTotalItems++;
    }
    getKeysFreeResult(&result);
}

/* Given a key name, this function sends an invalidation message in the
 * proper channel (depending on RESP version: PubSub or Push message) and