TT#189201 allow `to-label` usage for media blocking

This distinguishes `to-label` from `set-label` for media blocking
methods, when previously they were synonymous.

Upgrade sink determination to list at the same time.

Change-Id: I5b35c78f2f307867b51b5376d5a6afbd79128d99

README.md

@@ -695,7 +695,7 @@ Optionally included keys are:
 	back in logs and statistics output. For some commands (e.g. `block media`) the given label is not
 	used to set the label of the call participant, but rather to select an existing call participant.
 
-* `set-label` or `to-label`
+* `set-label`
 
 	Some commands (e.g. `block media`) use the given `label` to select
 	an existing call participant. For these commands, `set-label` instead
@@ -703,6 +703,15 @@ Optionally included keys are:
 	the selected call participant (if selected via `from-tag`) or for the
 	newly created participant (e.g. for `subscribe request`).
 
+* `to-label`
+
+	Commands that allow selection of two call participants (e.g. `block
+	media`) can use `label` instead of `from-tag` to select the first call
+	participant. The `to-label` can then be used instead of `to-tag` to
+	select the other call participant.
+
+	For `subscribe request` the `to-label` is synonymous with `set-label`.
+
 * `flags`
 
 	The value of the `flags` key is a list. The list contains zero or more of the following strings.
@@ -2014,7 +2023,7 @@ block media for just a single media flow. This is relevant to scenarios that
 involve forked media that were established with one or more `subscribe
 request`. To select just one media flow for media blocking, in addition to
 selecting a source call participant as above, a destination call participant
-must be specified using the `to-tag` key in the message.
+must be specified using the `to-tag` or `to-label`key in the message.
 
 `silence media` and `unsilence media` Messages
 ----------------------------------------------

daemon/call_interfaces.c

@@ -1105,10 +1105,12 @@ static void call_ng_main_flags(struct sdp_ng_flags *out, str *key, bencode_item_
 		case CSH_LOOKUP("label"):
 			out->label = s;
 			break;
-		case CSH_LOOKUP("to-label"):
 		case CSH_LOOKUP("set-label"):
 			out->set_label = s;
 			break;
+		case CSH_LOOKUP("to-label"):
+			out->to_label = s;
+			break;
 		case CSH_LOOKUP("address"):
 			out->address = s;
 			break;
@@ -2659,6 +2661,7 @@ static const char *call_block_silence_media(bencode_item_t *input, bool on_off,
 		return errstr;
 
 	if (monologue) {
+		AUTO_CLEANUP(GQueue sinks, g_queue_clear) = G_QUEUE_INIT;
 		if (flags.to_tag.len) {
 			struct call_monologue *sink = g_hash_table_lookup(call->tags, &flags.to_tag);
 			if (!sink) {
@@ -2668,6 +2671,22 @@ static const char *call_block_silence_media(bencode_item_t *input, bool on_off,
 						lcase_verb);
 				return "Media flow not found (to-tag not found)";
 			}
+			g_queue_push_tail(&sinks, sink);
+		}
+		else if (flags.to_label.len) {
+			struct call_monologue *sink = g_hash_table_lookup(call->labels, &flags.to_label);
+			if (!sink) {
+				ilog(LOG_WARN, "Media flow '" STR_FORMAT_M "' -> label '" STR_FORMAT "' doesn't "
+						"exist for media %s (to-label not found)",
+						STR_FMT_M(&monologue->tag), STR_FMT(&flags.to_label),
+						lcase_verb);
+				return "Media flow not found (to-label not found)";
+			}
+			g_queue_push_tail(&sinks, sink);
+		}
+		if (sinks.length) {
+			for (GList *l = sinks.head; l; l = l->next) {
+				struct call_monologue *sink = l->data;
 				GList *link = g_hash_table_lookup(monologue->subscribers_ht, sink);
 				if (!link) {
 					ilog(LOG_WARN, "Media flow '" STR_FORMAT_M "' -> '" STR_FORMAT_M "' doesn't "
@@ -2683,6 +2702,7 @@ static const char *call_block_silence_media(bencode_item_t *input, bool on_off,
 						ucase_verb,
 						STR_FMT_M(&monologue->tag), STR_FMT_M(&sink->tag));
 				G_STRUCT_MEMBER(bool, &cs->attrs, attr_offset) = on_off;
+			}
 			update_init_subscribers(monologue, OP_OTHER);
 		}
 		else {
@@ -2999,6 +3019,8 @@ const char *call_subscribe_request_ng(bencode_item_t *input, bencode_item_t *out
 	// the `label=` option was possibly used above to select the from-tag --
 	// switch it out with `to-label=` or `set-label=` for monologue_subscribe_request
 	// below which sets the label based on `label` for a newly created monologue
+	flags.label = flags.to_label;
+	if (flags.set_label.len) // set-label takes priority
 		flags.label = flags.set_label;
 
 	// get destination monologue

include/call_interfaces.h

@@ -40,6 +40,7 @@ struct sdp_ng_flags {
 	str metadata;
 	str label;
 	str set_label;
+	str to_label;
 	str address;
 	sockaddr_t xmlrpc_callback;
 	GQueue codec_strip;