C++ (Cpp) qb_rb_chunk_step Examples

Example #1

File: ringbuffer.c Project: ip1981/libqb

int32_t
qb_rb_chunk_commit(struct qb_ringbuffer_s * rb, size_t len)
{
	uint32_t old_write_pt;

	if (rb == NULL) {
		return -EINVAL;
	}
	/*
	 * commit the magic & chunk_size
	 */
	old_write_pt = rb->shared_hdr->write_pt;
	rb->shared_data[old_write_pt] = len;
	rb->shared_data[old_write_pt + 1] = QB_RB_CHUNK_MAGIC;

	/*
	 * commit the new write pointer
	 */
	rb->shared_hdr->write_pt = qb_rb_chunk_step(rb, old_write_pt);

	DEBUG_PRINTF("%s: read: %u, write: %u (was:%u)\n", __func__,
		     rb->shared_hdr->read_pt, rb->shared_hdr->write_pt,
		     old_write_pt);

	/*
	 * post the notification to the reader
	 */
	return rb->sem_post_fn(rb);
}

Example #2

File: ringbuffer.c Project: inouekazu/libqb

static int
_rb_chunk_reclaim(struct qb_ringbuffer_s * rb)
{
	uint32_t old_read_pt;
	uint32_t new_read_pt;
	uint32_t old_chunk_size;
	uint32_t chunk_magic;
	int rc = 0;

	old_read_pt = rb->shared_hdr->read_pt;
	chunk_magic = QB_RB_CHUNK_MAGIC_GET(rb, old_read_pt);
	if (chunk_magic != QB_RB_CHUNK_MAGIC) {
		return -EINVAL;
	}

	old_chunk_size = QB_RB_CHUNK_SIZE_GET(rb, old_read_pt);
	new_read_pt = qb_rb_chunk_step(rb, old_read_pt);

	/*
	 * clear the header
	 */
	rb->shared_data[old_read_pt] = 0;
	QB_RB_CHUNK_MAGIC_SET(rb, old_read_pt, QB_RB_CHUNK_MAGIC_DEAD);

	/*
	 * set the new read pointer after clearing the header
	 * to prevent a situation where a fast writer will write their
	 * new chunk between setting the new read pointer and clearing the
	 * header.
	 */
	rb->shared_hdr->read_pt = new_read_pt;

	if (rb->notifier.reclaim_fn) {
		rc = rb->notifier.reclaim_fn(rb->notifier.instance,
						 old_chunk_size);
		if (rc < 0) {
			errno = -rc;
			qb_util_perror(LOG_WARNING, "reclaim_fn");
		}
	}

	DEBUG_PRINTF("reclaim [%zd]: read: %u -> %u, write: %u\n",
		     (rb->notifier.q_len_fn ?
		      rb->notifier.q_len_fn(rb->notifier.instance) : 0),
		     old_read_pt,
		     rb->shared_hdr->read_pt,
		     rb->shared_hdr->write_pt);

	return rc;
}

Example #3

File: ringbuffer.c Project: ip1981/libqb

void
qb_rb_chunk_reclaim(struct qb_ringbuffer_s * rb)
{
	uint32_t old_read_pt;

	if (rb == NULL || qb_rb_space_used(rb) == 0) {
		return;
	}
	old_read_pt = rb->shared_hdr->read_pt;
	qb_rb_chunk_check(rb, old_read_pt);

	rb->shared_hdr->read_pt = qb_rb_chunk_step(rb, old_read_pt);

	/*
	 * clear the header
	 */
	rb->shared_data[old_read_pt] = 0;
	rb->shared_data[old_read_pt + 1] = 0;

	DEBUG_PRINTF("%s: read: %u (was:%u), write: %u\n", __func__,
		     rb->shared_hdr->read_pt, old_read_pt,
		     rb->shared_hdr->write_pt);
}

Example #4

File: ringbuffer.c Project: inouekazu/libqb

int32_t
qb_rb_chunk_commit(struct qb_ringbuffer_s * rb, size_t len)
{
	uint32_t old_write_pt;

	if (rb == NULL) {
		return -EINVAL;
	}
	/*
	 * commit the magic & chunk_size
	 */
	old_write_pt = rb->shared_hdr->write_pt;
	rb->shared_data[old_write_pt] = len;

	/*
	 * commit the new write pointer
	 */
	rb->shared_hdr->write_pt = qb_rb_chunk_step(rb, old_write_pt);
	QB_RB_CHUNK_MAGIC_SET(rb, old_write_pt, QB_RB_CHUNK_MAGIC);

	DEBUG_PRINTF("commit [%zd] read: %u, write: %u -> %u (%u)\n",
		     (rb->notifier.q_len_fn ?
		      rb->notifier.q_len_fn(rb->notifier.instance) : 0),
		     rb->shared_hdr->read_pt,
		     old_write_pt,
		     rb->shared_hdr->write_pt,
		     rb->shared_hdr->word_size);

	/*
	 * post the notification to the reader
	 */
	if (rb->notifier.post_fn) {
		return rb->notifier.post_fn(rb->notifier.instance, len);
	}
	return 0;
}