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;
}
static struct stasis_message_router *stasis_message_router_create_internal(
struct stasis_topic *topic, int use_thread_pool)
{
int res;
RAII_VAR(struct stasis_message_router *, router, NULL, ao2_cleanup);
router = ao2_t_alloc(sizeof(*router), router_dtor, stasis_topic_name(topic));
if (!router) {
return NULL;
}
res = 0;
res |= AST_VECTOR_INIT(&router->routes, 0);
res |= AST_VECTOR_INIT(&router->cache_routes, 0);
if (res) {
return NULL;
}
if (use_thread_pool) {
router->subscription = stasis_subscribe_pool(topic, router_dispatch, router);
} else {
router->subscription = stasis_subscribe(topic, router_dispatch, router);
}
if (!router->subscription) {
return NULL;
}
ao2_ref(router, +1);
return router;
}
static void caching_topic_exec(void *data, struct stasis_subscription *sub,
struct stasis_message *message)
{
RAII_VAR(struct stasis_caching_topic *, caching_topic_needs_unref, NULL, ao2_cleanup);
struct stasis_caching_topic *caching_topic = data;
const char *id = NULL;
ast_assert(caching_topic != NULL);
ast_assert(caching_topic->topic != NULL);
ast_assert(caching_topic->cache != NULL);
ast_assert(caching_topic->cache->id_fn != NULL);
if (stasis_subscription_final_message(sub, message)) {
caching_topic_needs_unref = caching_topic;
}
/* Handle cache clear event */
if (stasis_cache_clear_type() == stasis_message_type(message)) {
RAII_VAR(struct stasis_message *, old_snapshot, NULL, ao2_cleanup);
RAII_VAR(struct stasis_message *, update, NULL, ao2_cleanup);
struct stasis_message *clear_msg = stasis_message_data(message);
const char *clear_id = caching_topic->cache->id_fn(clear_msg);
struct stasis_message_type *clear_type = stasis_message_type(clear_msg);
ast_assert(clear_type != NULL);
if (clear_id) {
old_snapshot = cache_put(caching_topic->cache, clear_type, clear_id, NULL);
if (old_snapshot) {
update = update_create(old_snapshot, NULL);
stasis_publish(caching_topic->topic, update);
return;
}
ast_log(LOG_ERROR,
"Attempting to remove an item from the %s cache that isn't there: %s %s\n",
stasis_topic_name(caching_topic->topic), stasis_message_type_name(clear_type), clear_id);
return;
}
}
id = caching_topic->cache->id_fn(message);
if (id == NULL) {
/* Object isn't cached; discard */
} else {
/* Update the cache */
RAII_VAR(struct stasis_message *, old_snapshot, NULL, ao2_cleanup);
RAII_VAR(struct stasis_message *, update, NULL, ao2_cleanup);
old_snapshot = cache_put(caching_topic->cache, stasis_message_type(message), id, message);
update = update_create(old_snapshot, message);
if (update == NULL) {
return;
}
stasis_publish(caching_topic->topic, update);
}
}
static int topic_pool_entry_cmp(void *obj, void *arg, int flags)
{
const struct topic_pool_entry *object_left = obj;
const struct topic_pool_entry *object_right = arg;
const char *right_key = arg;
int cmp;
switch (flags & OBJ_SEARCH_MASK) {
case OBJ_SEARCH_OBJECT:
right_key = stasis_topic_name(object_right->topic);
/* Fall through */
case OBJ_SEARCH_KEY:
cmp = strcasecmp(stasis_topic_name(object_left->topic), right_key);
break;
case OBJ_SEARCH_PARTIAL_KEY:
/* Not supported by container */
ast_assert(0);
cmp = -1;
break;
default:
/*
* What arg points to is specific to this traversal callback
* and has no special meaning to astobj2.
*/
cmp = 0;
break;
}
if (cmp) {
return 0;
}
/*
* At this point the traversal callback is identical to a sorted
* container.
*/
return CMP_MATCH;
}
static int topic_pool_entry_hash(const void *obj, const int flags)
{
const struct topic_pool_entry *object;
const char *key;
switch (flags & OBJ_SEARCH_MASK) {
case OBJ_SEARCH_KEY:
key = obj;
break;
case OBJ_SEARCH_OBJECT:
object = obj;
key = stasis_topic_name(object->topic);
break;
default:
/* Hash can only work on something with a full key. */
ast_assert(0);
return 0;
}
return ast_str_case_hash(key);
}
struct stasis_caching_topic *stasis_caching_topic_create(struct stasis_topic *original_topic, struct stasis_cache *cache)
{
RAII_VAR(struct stasis_caching_topic *, caching_topic, NULL, ao2_cleanup);
struct stasis_subscription *sub;
RAII_VAR(char *, new_name, NULL, ast_free);
int ret;
ret = ast_asprintf(&new_name, "%s-cached", stasis_topic_name(original_topic));
if (ret < 0) {
return NULL;
}
caching_topic = ao2_alloc_options(sizeof(*caching_topic),
stasis_caching_topic_dtor, AO2_ALLOC_OPT_LOCK_NOLOCK);
if (caching_topic == NULL) {
return NULL;
}
caching_topic->topic = stasis_topic_create(new_name);
if (caching_topic->topic == NULL) {
return NULL;
}
ao2_ref(cache, +1);
caching_topic->cache = cache;
sub = internal_stasis_subscribe(original_topic, caching_topic_exec, caching_topic, 0);
if (sub == NULL) {
return NULL;
}
ao2_ref(original_topic, +1);
caching_topic->original_topic = original_topic;
/* This is for the reference contained in the subscription above */
ao2_ref(caching_topic, +1);
caching_topic->sub = sub;
/* The subscription holds the reference, so no additional ref bump. */
return caching_topic;
}
