Function RM_GetCommandKeys

app/redis-6.2.6/src/module.c:8981–9027

For a specified command, parse its arguments and return an array that * contains the indexes of all key name arguments. This function is * essnetially a more efficient way to do COMMAND GETKEYS. * * A NULL return value indicates the specified command has no keys, or * an error condition. Error conditions are indicated by setting errno * as folllows: * * * ENOENT: Specified command does not

 * must explicitly call RM_Free() to free it.
 */
int *RM_GetCommandKeys(RedisModuleCtx *ctx, RedisModuleString **argv, int argc, int *num_keys) {
    UNUSED(ctx);
    struct redisCommand *cmd;
    int *res = NULL;

    /* Find command */
    if ((cmd = lookupCommand(argv[0]->ptr)) == NULL) {
        errno = ENOENT;
        return NULL;
    }

    /* Bail out if command has no keys */
    if (cmd->getkeys_proc == NULL && cmd->firstkey == 0) {
        errno = 0;
        return NULL;
    }

    if ((cmd->arity > 0 && cmd->arity != argc) || (argc < -cmd->arity)) {
        errno = EINVAL;
        return NULL;
    }

    getKeysResult result = GETKEYS_RESULT_INIT;
    getKeysFromCommand(cmd, argv, argc, &result);

    *num_keys = result.numkeys;
    if (!result.numkeys) {
        errno = 0;
        getKeysFreeResult(&result);
        return NULL;
    }

    if (result.keys == result.keysbuf) {
        /* If the result is using a stack based array, copy it. */
        unsigned long int size = sizeof(int) * result.numkeys;
        res = zmalloc(size);
        memcpy(res, result.keys, size);
    } else {
        /* We return the heap based array and intentionally avoid calling
         * getKeysFreeResult() here, as it is the caller's responsibility
         * to free this array.
         */
        res = result.keys;
    }

    return res;
}

/* Return the name of the command currently running */
const char *RM_GetCurrentCommandName(RedisModuleCtx *ctx) {