adding functions create_worker_subscriber_channel_sentinel_locked,...

adding functions create_worker_subscriber_channel_sentinel_locked, create_channel_subscription and assing_subscription_to_channel_locked to group the logics responsable to add a subscriber to a channel

src/ngx_http_push_stream_module_subscriber.c

@@ -28,6 +28,9 @@
 static ngx_http_push_stream_worker_subscriber_t *ngx_http_push_stream_subscriber_prepare_request_to_keep_connected(ngx_http_request_t *r);
 static void                                      ngx_http_push_stream_registry_subscriber_locked(ngx_http_push_stream_worker_subscriber_t *worker_subscriber);
 static void                                      ngx_http_push_stream_send_old_messages(ngx_http_request_t *r, ngx_http_push_stream_channel_t *channel, ngx_uint_t backtrack, time_t if_modified_since);
+static ngx_http_push_stream_pid_queue_t         *ngx_http_push_stream_create_worker_subscriber_channel_sentinel_locked(ngx_slab_pool_t *shpool, ngx_str_t *channel_id, ngx_log_t *log);
+static ngx_http_push_stream_subscription_t      *ngx_http_push_stream_create_channel_subscription(ngx_http_request_t *r, ngx_http_push_stream_channel_t *channel);
+static ngx_int_t                                 ngx_http_push_stream_assing_subscription_to_channel_locked(ngx_str_t *channel_id, ngx_http_push_stream_subscription_t *subscription, ngx_http_push_stream_subscription_t *subscriptions_sentinel, ngx_http_push_stream_pid_queue_t *worker_subscribers_sentinel, ngx_log_t *log);
 
 static ngx_int_t
 ngx_http_push_stream_subscriber_handler(ngx_http_request_t *r)
@@ -158,88 +161,47 @@ ngx_http_push_stream_subscriber_handler(ngx_http_request_t *r)
 static ngx_int_t
 ngx_http_push_stream_subscriber_assign_channel(ngx_slab_pool_t *shpool, ngx_http_push_stream_loc_conf_t *cf, ngx_http_request_t *r, ngx_http_push_stream_requested_channel_t *requested_channel, time_t if_modified_since, ngx_http_push_stream_subscription_t *subscriptions_sentinel, ngx_pool_t *temp_pool)
 {
-    ngx_http_push_stream_pid_queue_t           *sentinel, *cur, *found;
+    ngx_http_push_stream_pid_queue_t           *cur, *worker_subscribers_sentinel = NULL;
     ngx_http_push_stream_channel_t             *channel;
-    ngx_http_push_stream_subscriber_t          *subscriber;
-    ngx_http_push_stream_subscriber_t          *subscriber_sentinel;
     ngx_http_push_stream_subscription_t        *subscription;
+    ngx_int_t                                   result;
 
-    channel = ngx_http_push_stream_find_channel(requested_channel->id, r->connection->log);
-    if (channel == NULL) {
+    if ((channel = ngx_http_push_stream_find_channel(requested_channel->id, r->connection->log)) == NULL) {
         // channel not found
         ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "push stream module: unable to allocate shared memory for channel %s", requested_channel->id->data);
         return NGX_ERROR;
     }
 
-    sentinel = &channel->workers_with_subscribers;
-    cur = sentinel;
+    cur = &channel->workers_with_subscribers;
 
-    found = NULL;
-    while ((cur = (ngx_http_push_stream_pid_queue_t *) ngx_queue_next(&cur->queue)) != sentinel) {
+    while ((cur = (ngx_http_push_stream_pid_queue_t *) ngx_queue_next(&cur->queue)) != &channel->workers_with_subscribers) {
         if (cur->pid == ngx_pid) {
-            found = cur;
+            worker_subscribers_sentinel = cur;
             break;
         }
     }
 
-    if (found == NULL) { // found nothing
+    if (worker_subscribers_sentinel == NULL) { // found nothing
         ngx_shmtx_lock(&shpool->mutex);
-        // check if channel still exists
-        channel = ngx_http_push_stream_find_channel_locked(requested_channel->id, r->connection->log);
-        if (channel == NULL) {
-            ngx_shmtx_unlock(&(shpool)->mutex);
-            ngx_log_error(NGX_LOG_ERR, (r)->connection->log, 0, "push stream module: something goes very wrong, arrived on ngx_http_push_stream_subscriber_assign_channel without created channel %s", requested_channel->id->data);
-            return NGX_ERROR;
-        }
-
-        if ((found = ngx_slab_alloc_locked(shpool, sizeof(ngx_http_push_stream_pid_queue_t))) == NULL) {
-            ngx_shmtx_unlock(&shpool->mutex);
-            ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "push stream module: unable to allocate worker subscriber queue marker in shared memory");
+        worker_subscribers_sentinel = ngx_http_push_stream_create_worker_subscriber_channel_sentinel_locked(shpool, requested_channel->id, r->connection->log);
+        ngx_shmtx_unlock(&shpool->mutex);
+        if (worker_subscribers_sentinel == NULL) {
             return NGX_ERROR;
         }
-        // initialize
-        ngx_queue_insert_tail(&sentinel->queue, &found->queue);
-
-        found->pid = ngx_pid;
-        found->slot = ngx_process_slot;
-        ngx_queue_init(&found->subscriber_sentinel.queue);
-        ngx_shmtx_unlock(&shpool->mutex);
     }
 
-    if ((subscription = ngx_palloc(r->pool, sizeof(ngx_http_push_stream_subscription_t))) == NULL) {
-        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "push stream module: unable to allocate subscribed channel reference");
-        return NGX_ERROR;
-    }
-
-    if ((subscriber = ngx_palloc(r->pool, sizeof(ngx_http_push_stream_subscriber_t))) == NULL) { // unable to allocate request queue element
-        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "push stream module: unable to allocate subscribed channel reference");
+    if ((subscription = ngx_http_push_stream_create_channel_subscription(r, channel)) == NULL) {
         return NGX_ERROR;
     }
 
-    subscriber_sentinel = &found->subscriber_sentinel;
-
-    subscriber->request = r;
-
-    subscription->channel = channel;
-    subscription->subscriber = subscriber;
-
     // send old messages to new subscriber
     ngx_http_push_stream_send_old_messages(r, channel, requested_channel->backtrack_messages, if_modified_since);
 
     ngx_shmtx_lock(&shpool->mutex);
-    // check if channel still exists
-    channel = ngx_http_push_stream_find_channel_locked(requested_channel->id, r->connection->log);
-    if (channel == NULL) {
-        ngx_shmtx_unlock(&(shpool)->mutex);
-        ngx_log_error(NGX_LOG_ERR, (r)->connection->log, 0, "push stream module: something goes very wrong, arrived on ngx_http_push_stream_subscriber_assign_channel without created channel %s", requested_channel->id->data);
-        return NGX_ERROR;
-    }
-    channel->subscribers++; // do this only when we know everything went okay
-    ngx_queue_insert_tail(&subscriptions_sentinel->queue, &subscription->queue);
-    ngx_queue_insert_tail(&subscriber_sentinel->queue, &subscriber->queue);
+    result = ngx_http_push_stream_assing_subscription_to_channel_locked(requested_channel->id, subscription, subscriptions_sentinel, worker_subscribers_sentinel, r->connection->log);
     ngx_shmtx_unlock(&shpool->mutex);
 
-    return NGX_OK;
+    return result;
 }
 
 ngx_http_push_stream_requested_channel_t *
@@ -429,3 +391,70 @@ ngx_http_push_stream_send_old_messages(ngx_http_request_t *r, ngx_http_push_stre
         }
     }
 }
+
+static ngx_http_push_stream_pid_queue_t *
+ngx_http_push_stream_create_worker_subscriber_channel_sentinel_locked(ngx_slab_pool_t *shpool, ngx_str_t *channel_id, ngx_log_t *log)
+{
+    ngx_http_push_stream_pid_queue_t     *worker_sentinel;
+    ngx_http_push_stream_channel_t       *channel;
+
+    // check if channel still exists
+    if ((channel = ngx_http_push_stream_find_channel_locked(channel_id, log)) == NULL) {
+        ngx_log_error(NGX_LOG_ERR, log, 0, "push stream module: something goes very wrong, arrived on ngx_http_push_stream_subscriber_assign_channel without created channel %s", channel_id->data);
+        return NULL;
+    }
+
+    if ((worker_sentinel = ngx_slab_alloc_locked(shpool, sizeof(ngx_http_push_stream_pid_queue_t))) == NULL) {
+        ngx_log_error(NGX_LOG_ERR, log, 0, "push stream module: unable to allocate worker subscriber queue marker in shared memory");
+        return NULL;
+    }
+
+    // initialize
+    ngx_queue_insert_tail(&channel->workers_with_subscribers.queue, &worker_sentinel->queue);
+
+    worker_sentinel->pid = ngx_pid;
+    worker_sentinel->slot = ngx_process_slot;
+    ngx_queue_init(&worker_sentinel->subscriber_sentinel.queue);
+
+    return worker_sentinel;
+}
+
+static ngx_http_push_stream_subscription_t *
+ngx_http_push_stream_create_channel_subscription(ngx_http_request_t *r, ngx_http_push_stream_channel_t *channel)
+{
+    ngx_http_push_stream_subscription_t        *subscription;
+    ngx_http_push_stream_subscriber_t          *subscriber;
+
+    if ((subscription = ngx_palloc(r->pool, sizeof(ngx_http_push_stream_subscription_t))) == NULL) {
+        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "push stream module: unable to allocate subscribed channel reference");
+        return NULL;
+    }
+
+    if ((subscriber = ngx_palloc(r->pool, sizeof(ngx_http_push_stream_subscriber_t))) == NULL) { // unable to allocate request queue element
+        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "push stream module: unable to allocate subscribed channel reference");
+        return NULL;
+    }
+
+    subscriber->request = r;
+
+    subscription->channel = channel;
+    subscription->subscriber = subscriber;
+
+    return subscription;
+}
+
+static ngx_int_t
+ngx_http_push_stream_assing_subscription_to_channel_locked(ngx_str_t *channel_id, ngx_http_push_stream_subscription_t *subscription, ngx_http_push_stream_subscription_t *subscriptions_sentinel, ngx_http_push_stream_pid_queue_t *worker_subscribers_sentinel, ngx_log_t *log)
+{
+	ngx_http_push_stream_channel_t *channel;
+
+	// check if channel still exists
+	if ((channel = ngx_http_push_stream_find_channel_locked(channel_id, log)) == NULL) {
+		ngx_log_error(NGX_LOG_ERR, log, 0, "push stream module: something goes very wrong, arrived on ngx_http_push_stream_subscriber_assign_channel without created channel %s", channel_id->data);
+		return NGX_ERROR;
+	}
+	channel->subscribers++; // do this only when we know everything went okay
+	ngx_queue_insert_tail(&subscriptions_sentinel->queue, &subscription->queue);
+	ngx_queue_insert_tail(&worker_subscribers_sentinel->subscriber_sentinel.queue, &subscription->subscriber->queue);
+	return NGX_OK;
+}