struct stasis_subscription *internal_stasis_subscribe(
struct stasis_topic *topic,
stasis_subscription_cb callback,
void *data,
int needs_mailbox,
int use_thread_pool)
{
RAII_VAR(struct stasis_subscription *, sub, NULL, ao2_cleanup);
if (!topic) {
return NULL;
}
/* The ao2 lock is used for join_cond. */
sub = ao2_t_alloc(sizeof(*sub), subscription_dtor, stasis_topic_name(topic));
if (!sub) {
return NULL;
}
ast_uuid_generate_str(sub->uniqueid, sizeof(sub->uniqueid));
if (needs_mailbox) {
char tps_name[AST_TASKPROCESSOR_MAX_NAME + 1];
/* Create name with seq number appended. */
ast_taskprocessor_build_name(tps_name, sizeof(tps_name), "sub%c:%s",
use_thread_pool ? 'p' : 'm',
stasis_topic_name(topic));
/*
* With a small number of subscribers, a thread-per-sub is
* acceptable. For a large number of subscribers, a thread
* pool should be used.
*/
if (use_thread_pool) {
sub->mailbox = ast_threadpool_serializer(tps_name, pool);
} else {
sub->mailbox = ast_taskprocessor_get(tps_name, TPS_REF_DEFAULT);
}
if (!sub->mailbox) {
return NULL;
}
ast_taskprocessor_set_local(sub->mailbox, sub);
/* Taskprocessor has a reference */
ao2_ref(sub, +1);
}
ao2_ref(topic, +1);
sub->topic = topic;
sub->callback = callback;
sub->data = data;
ast_cond_init(&sub->join_cond, NULL);
if (topic_add_subscription(topic, sub) != 0) {
return NULL;
}
send_subscription_subscribe(topic, sub);
ao2_ref(sub, +1);
return sub;
}
struct stasis_subscription *internal_stasis_subscribe(
struct stasis_topic *topic,
stasis_subscription_cb callback,
void *data,
int needs_mailbox,
int use_thread_pool)
{
RAII_VAR(struct stasis_subscription *, sub, NULL, ao2_cleanup);
if (!topic) {
return NULL;
}
/* The ao2 lock is used for join_cond. */
sub = ao2_t_alloc(sizeof(*sub), subscription_dtor, topic->name);
if (!sub) {
return NULL;
}
ast_uuid_generate_str(sub->uniqueid, sizeof(sub->uniqueid));
if (needs_mailbox) {
/* With a small number of subscribers, a thread-per-sub is
* acceptable. For larger number of subscribers, a thread
* pool should be used.
*/
if (use_thread_pool) {
sub->mailbox = ast_threadpool_serializer(sub->uniqueid, pool);
} else {
sub->mailbox = ast_taskprocessor_get(sub->uniqueid,
TPS_REF_DEFAULT);
}
if (!sub->mailbox) {
return NULL;
}
ast_taskprocessor_set_local(sub->mailbox, sub);
/* Taskprocessor has a reference */
ao2_ref(sub, +1);
}
ao2_ref(topic, +1);
sub->topic = topic;
sub->callback = callback;
sub->data = data;
ast_cond_init(&sub->join_cond, NULL);
if (topic_add_subscription(topic, sub) != 0) {
return NULL;
}
send_subscription_subscribe(topic, sub);
ao2_ref(sub, +1);
return sub;
}
/*!
* \brief Add a subscriber to a topic.
* \param topic Topic
* \param sub Subscriber
* \return 0 on success
* \return Non-zero on error
*/
static int topic_add_subscription(struct stasis_topic *topic, struct stasis_subscription *sub)
{
size_t idx;
SCOPED_AO2LOCK(lock, topic);
/* The reference from the topic to the subscription is shared with
* the owner of the subscription, which will explicitly unsubscribe
* to release it.
*
* If we bumped the refcount here, the owner would have to unsubscribe
* and cleanup, which is a bit awkward. */
AST_VECTOR_APPEND(&topic->subscribers, sub);
for (idx = 0; idx < AST_VECTOR_SIZE(&topic->upstream_topics); ++idx) {
topic_add_subscription(
AST_VECTOR_GET(&topic->upstream_topics, idx), sub);
}
return 0;
}
struct stasis_forward *stasis_forward_all(struct stasis_topic *from_topic,
struct stasis_topic *to_topic)
{
int res;
size_t idx;
RAII_VAR(struct stasis_forward *, forward, NULL, ao2_cleanup);
if (!from_topic || !to_topic) {
return NULL;
}
forward = ao2_alloc_options(sizeof(*forward), forward_dtor, AO2_ALLOC_OPT_LOCK_NOLOCK);
if (!forward) {
return NULL;
}
/* Forwards to ourselves are implicit. */
if (to_topic == from_topic) {
return ao2_bump(forward);
}
forward->from_topic = ao2_bump(from_topic);
forward->to_topic = ao2_bump(to_topic);
topic_lock_both(to_topic, from_topic);
res = AST_VECTOR_APPEND(&to_topic->upstream_topics, from_topic);
if (res != 0) {
ao2_unlock(from_topic);
ao2_unlock(to_topic);
return NULL;
}
for (idx = 0; idx < AST_VECTOR_SIZE(&to_topic->subscribers); ++idx) {
topic_add_subscription(from_topic, AST_VECTOR_GET(&to_topic->subscribers, idx));
}
ao2_unlock(from_topic);
ao2_unlock(to_topic);
return ao2_bump(forward);
}
