MT#61625 make recursive update_init_subs

Instead of explicitly triggering an update of subscribers for A and B
during an offer/answer, trigger it only for one side (A) and then
iterate through all subscribers and subsriptions and update them all.
This automatically triggers an update for B, as well as any other
existing subscriptions that might be affected. Use a monotonically
increading update iterator counter to track which medias have been
updated so we don't run into infinite recursion.

Change-Id: Ie2fba8ff9c5a011bbe932559ac06e1634029a091

daemon/call.c

@@ -2621,8 +2621,12 @@ void codecs_offer_answer(struct call_media *media, struct call_media *other_medi
 /* called with call->master_lock held in W */
 __attribute__((nonnull(1)))
 static void __update_init_subscribers(struct call_media *media, struct stream_params *sp,
-		sdp_ng_flags *flags, enum ng_opmode opmode)
+		sdp_ng_flags *flags, enum ng_opmode opmode, unsigned int iter)
 {
+	if (media->update_iter == iter)
+		return;
+	media->update_iter = iter;
+
 	recording_setup_media(media);
 
 	/* should be set on media directly? Currently absent */
@@ -2643,6 +2647,13 @@ static void __update_init_subscribers(struct call_media *media, struct stream_pa
 		struct call_media * sub_media = ms->media;
 		if (!__streams_set_sinks(media, sub_media, flags, &ms->attrs))
 			ilog(LOG_WARN, "Error initialising streams");
+		__update_init_subscribers(sub_media, NULL, NULL, opmode, iter);
+	}
+	for (__auto_type l = media->media_subscriptions.head; l; l = l->next)
+	{
+		struct media_subscription * ms = l->data;
+		struct call_media *sub_media = ms->media;
+		__update_init_subscribers(sub_media, NULL, NULL, opmode, iter);
 	}
 
 	/* we are now ready to fire up ICE if so desired and requested */
@@ -2663,21 +2674,36 @@ static void __update_init_subscribers(struct call_media *media, struct stream_pa
 		mqtt_timer_start(&media->mqtt_timer, media->call, media);
 }
 
+__attribute__((nonnull(1)))
+static void update_init_subscribers(struct call_media *media, struct stream_params *sp,
+		sdp_ng_flags *flags, enum ng_opmode opmode)
+{
+	g_autoptr(GHashTable) recurs_ht = g_hash_table_new(g_direct_hash, g_direct_equal);
+	__update_init_subscribers(media, sp, flags, opmode, ++media->call->update_iter);
+}
+
 /* called with call->master_lock held in W */
 void update_init_monologue_subscribers(struct call_monologue *ml, enum ng_opmode opmode) {
+	unsigned int update_iter = ++ml->call->update_iter;
+
 	for (unsigned int i = 0; i < ml->medias->len; i++)
 	{
 		struct call_media *media = ml->medias->pdata[i];
 		if (!media)
 			continue;
-		__update_init_subscribers(media, NULL, NULL, opmode);
+		__update_init_subscribers(media, NULL, NULL, opmode, update_iter);
 	}
 }
 
 /* called with call->master_lock held in W */
 static void __update_init_medias(const medias_q *medias, enum ng_opmode opmode) {
+	if (!medias->length)
+		return;
+
+	unsigned int update_iter = ++medias->head->data->call->update_iter;
+
 	for (auto_iter(l, medias->head); l; l = l->next)
-		__update_init_subscribers(l->data, NULL, NULL, opmode);
+		__update_init_subscribers(l->data, NULL, NULL, opmode, update_iter);
 }
 
 /* called with call->master_lock held in W */
@@ -3238,8 +3264,7 @@ int monologue_offer_answer(struct call_monologue *monologues[2], sdp_streams_q *
 				goto error_ports;
 		}
 
-		__update_init_subscribers(sender_media, sp, flags, flags->opmode);
+		update_init_subscribers(sender_media, sp, flags, flags->opmode);
-		__update_init_subscribers(receiver_media, NULL, NULL, flags->opmode);
 		__update_init_medias(&old_medias, flags->opmode);
 
 		media_update_transcoding_flag(receiver_media);
@@ -3657,8 +3682,7 @@ static int monologue_subscribe_request1(struct call_monologue *src_ml, struct ca
 		if (!__init_streams(dst_media, NULL, flags))
 			return -1;
 
-		__update_init_subscribers(src_media, NULL, NULL, flags->opmode);
+		update_init_subscribers(src_media, NULL, NULL, flags->opmode);
-		__update_init_subscribers(dst_media, NULL, NULL, flags->opmode);
 	}
 
 	return 0;
@@ -3750,7 +3774,7 @@ int monologue_subscribe_answer(struct call_monologue *dst_ml, sdp_ng_flags *flag
 		/* TODO: check answer SDP parameters */
 		MEDIA_SET(dst_media, INITIALIZED);
 
-		__update_init_subscribers(dst_media, sp, flags, flags->opmode);
+		update_init_subscribers(dst_media, sp, flags, flags->opmode);
 		__media_unconfirm(dst_media, "subscribe answer event");
 	}
 
@@ -3768,7 +3792,7 @@ int monologue_subscribe_answer(struct call_monologue *dst_ml, sdp_ng_flags *flag
 			struct media_subscription * ms = sub->data;
 			if (!g_queue_find(&mls, ms->monologue)) {
 				media_update_transcoding_flag(ms->media);
-				__update_init_subscribers(ms->media, NULL, NULL, flags->opmode);
+				update_init_subscribers(ms->media, NULL, NULL, flags->opmode);
 				__media_unconfirm(ms->media, "subscribe answer event");
 				g_queue_push_tail(&mls, ms->monologue);
 			}
@@ -3798,12 +3822,12 @@ int monologue_unsubscribe(struct call_monologue *dst_ml, sdp_ng_flags *flags) {
 
 			__media_unconfirm(src_media, "media unsubscribe");
 			__unsubscribe_media_link(media, l);
-			__update_init_subscribers(src_media, NULL, NULL, flags->opmode);
+			update_init_subscribers(src_media, NULL, NULL, flags->opmode);
 
 			l = next;
 		}
 
-		__update_init_subscribers(media, NULL, NULL, flags->opmode);
+		update_init_subscribers(media, NULL, NULL, flags->opmode);
 	}
 
 	return 0;
@@ -3863,8 +3887,7 @@ void dialogue_connect(struct call_monologue *src_ml, struct call_monologue *dst_
 		codec_handlers_update(dst_media, src_media,
 				.allow_asymmetric = !!flags->allow_asymmetric_codecs);
 
-		__update_init_subscribers(src_media, NULL, NULL, flags->opmode);
+		update_init_subscribers(src_media, NULL, NULL, flags->opmode);
-		__update_init_subscribers(dst_media, NULL, NULL, flags->opmode);
 		__update_init_medias(&medias, flags->opmode);
 	}
 }

include/call.h

@@ -557,6 +557,7 @@ struct call_media {
 	int			maxptime;			/* from SDP */
 
 	atomic64		media_flags;
+	unsigned int		update_iter;
 };
 
 TYPED_GPTRARRAY(medias_arr, struct call_media)
@@ -798,6 +799,7 @@ struct call {
 	enum block_dtmf_mode	block_dtmf;
 
 	atomic64		call_flags;
+	unsigned int		update_iter;
 	unsigned int media_rec_slots;
 };