ssize_t qb_rb_chunk_peek(struct qb_ringbuffer_s * rb, void **data_out, int32_t timeout) { uint32_t read_pt; uint32_t chunk_size; uint32_t chunk_magic; int32_t res; if (rb == NULL) { return -EINVAL; } res = rb->sem_timedwait_fn(rb, timeout); if (res < 0 && res != -EIDRM) { if (res != -ETIMEDOUT) { qb_util_perror(LOG_ERR, "sem_timedwait"); } return res; } read_pt = rb->shared_hdr->read_pt; chunk_size = QB_RB_CHUNK_SIZE_GET(rb, read_pt); chunk_magic = QB_RB_CHUNK_MAGIC_GET(rb, read_pt); *data_out = &rb->shared_data[read_pt + QB_RB_CHUNK_HEADER_WORDS]; if (chunk_magic != QB_RB_CHUNK_MAGIC) { errno = ENOMSG; return 0; } else { return chunk_size; } }
ssize_t qb_rb_chunk_peek(struct qb_ringbuffer_s * rb, void **data_out, int32_t timeout) { uint32_t read_pt; uint32_t chunk_size; uint32_t chunk_magic; int32_t res = 0; if (rb == NULL) { return -EINVAL; } if (rb->notifier.timedwait_fn) { res = rb->notifier.timedwait_fn(rb->notifier.instance, timeout); } if (res < 0 && res != -EIDRM) { if (res == -ETIMEDOUT) { return 0; } else { errno = -res; qb_util_perror(LOG_ERR, "sem_timedwait"); } return res; } read_pt = rb->shared_hdr->read_pt; chunk_magic = QB_RB_CHUNK_MAGIC_GET(rb, read_pt); if (chunk_magic != QB_RB_CHUNK_MAGIC) { if (rb->notifier.post_fn) { (void)rb->notifier.post_fn(rb->notifier.instance, res); } return 0; } chunk_size = QB_RB_CHUNK_SIZE_GET(rb, read_pt); *data_out = QB_RB_CHUNK_DATA_GET(rb, read_pt); return chunk_size; }
ssize_t qb_rb_chunk_read(struct qb_ringbuffer_s * rb, void *data_out, size_t len, int32_t timeout) { uint32_t read_pt; uint32_t chunk_size; uint32_t chunk_magic; int32_t res = 0; if (rb == NULL) { return -EINVAL; } if (rb->notifier.timedwait_fn) { res = rb->notifier.timedwait_fn(rb->notifier.instance, timeout); } if (res < 0 && res != -EIDRM) { if (res != -ETIMEDOUT) { errno = -res; qb_util_perror(LOG_ERR, "sem_timedwait"); } return res; } read_pt = rb->shared_hdr->read_pt; chunk_magic = QB_RB_CHUNK_MAGIC_GET(rb, read_pt); if (chunk_magic != QB_RB_CHUNK_MAGIC) { if (rb->notifier.timedwait_fn == NULL) { return -ETIMEDOUT; } else { (void)rb->notifier.post_fn(rb->notifier.instance, res); #ifdef EBADMSG return -EBADMSG; #else return -EINVAL; #endif } } chunk_size = QB_RB_CHUNK_SIZE_GET(rb, read_pt); if (len < chunk_size) { qb_util_log(LOG_ERR, "trying to recv chunk of size %d but %d available", len, chunk_size); if (rb->notifier.post_fn) { (void)rb->notifier.post_fn(rb->notifier.instance, chunk_size); } return -ENOBUFS; } memcpy(data_out, QB_RB_CHUNK_DATA_GET(rb, read_pt), chunk_size); _rb_chunk_reclaim(rb); return chunk_size; }
static void qb_rb_chunk_check(struct qb_ringbuffer_s * rb, uint32_t pointer) { uint32_t chunk_size; uint32_t chunk_magic = QB_RB_CHUNK_MAGIC_GET(rb, pointer); if (chunk_magic != QB_RB_CHUNK_MAGIC) { chunk_size = QB_RB_CHUNK_SIZE_GET(rb, pointer); printf("size: %x\n", chunk_size); printf("magic: %x\n", chunk_magic); print_header(rb); assert(0); } }
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; }