Function RM_StreamTrimByLength

app/redis-6.2.6/src/module.c:3701–3714

Trim a stream by length, similar to XTRIM with MAXLEN. * * - `key`: Key opened for writing. * - `flags`: A bitfield of * - `REDISMODULE_STREAM_TRIM_APPROX`: Trim less if it improves performance, * like XTRIM with `~`. * - `length`: The number of stream entries to keep after trimming. * * Returns the number of entries deleted. On failure, a negative value is * returned and `errno` is

 * - EBADF if the key is not opened for writing
 */
long long RM_StreamTrimByLength(RedisModuleKey *key, int flags, long long length) {
    if (!key || (flags & ~(REDISMODULE_STREAM_TRIM_APPROX)) || length < 0) {
        errno = EINVAL;
        return -1;
    } else if (!key->value || key->value->type != OBJ_STREAM) {
        errno = ENOTSUP;
        return -1;
    } else if (!(key->mode & REDISMODULE_WRITE)) {
        errno = EBADF;
        return -1;
    }
    int approx = flags & REDISMODULE_STREAM_TRIM_APPROX ? 1 : 0;
    return streamTrimByLength((stream *)key->value->ptr, length, approx);
}

/* Trim a stream by ID, similar to XTRIM with MINID.
 *