Function SDL_ClearDataQueue

deps/SDL2/src/SDL_dataqueue.c:97–138

}

void
SDL_ClearDataQueue(SDL_DataQueue *queue, const size_t slack)
{
    const size_t packet_size = queue ? queue->packet_size : 1;
    const size_t slackpackets = (slack + (packet_size-1)) / packet_size;
    SDL_DataQueuePacket *packet;
    SDL_DataQueuePacket *prev = NULL;
    size_t i;

    if (!queue) {
        return;
    }

    packet = queue->head;

    /* merge the available pool and the current queue into one list. */
    if (packet) {
        queue->tail->next = queue->pool;
    } else {
        packet = queue->pool;
    }

    /* Remove the queued packets from the device. */
    queue->tail = NULL;
    queue->head = NULL;
    queue->queued_bytes = 0;
    queue->pool = packet;

    /* Optionally keep some slack in the pool to reduce malloc pressure. */
    for (i = 0; packet && (i < slackpackets); i++) {
        prev = packet;
        packet = packet->next;
    }

    if (prev) {
        prev->next = NULL;
    } else {
        queue->pool = NULL;
    }

    SDL_FreeDataQueueList(packet);  /* free extra packets */
}

static SDL_DataQueuePacket *
AllocateDataQueuePacket(SDL_DataQueue *queue)