新增mk_media_source_broadcast_msg接口

通过该接口可以广播webrtc datachannel消息给webrtc播放器

api/include/mk_events_objects.h

@@ -100,6 +100,9 @@ API_EXPORT int API_CALL mk_media_source_get_total_reader_count(const mk_media_so
 API_EXPORT int API_CALL mk_media_source_get_track_count(const mk_media_source ctx);
 // copy track reference by index from MediaSource, please use mk_track_unref to release it
 API_EXPORT mk_track API_CALL mk_media_source_get_track(const mk_media_source ctx, int index);
+// MediaSource::broadcastMessage
+API_EXPORT int API_CALL mk_media_source_broadcast_msg(const mk_media_source ctx, const char *msg, size_t len);
+
 /**
  * 直播源在ZLMediaKit中被称作为MediaSource，
  * 目前支持3种，分别是RtmpMediaSource、RtspMediaSource、HlsMediaSource

api/source/mk_events_objects.cpp

@@ -214,6 +214,16 @@ API_EXPORT mk_track API_CALL mk_media_source_get_track(const mk_media_source ctx
     return (mk_track) new Track::Ptr(std::move(tracks[index]));
 }
 
+API_EXPORT int API_CALL mk_media_source_broadcast_msg(const mk_media_source ctx, const char *msg, size_t len) {
+    assert(ctx && msg && len);
+    MediaSource *src = (MediaSource *)ctx;
+
+    Any any;
+    Buffer::Ptr buffer = std::make_shared<BufferLikeString>(std::string(msg, len));
+    any.set(std::move(buffer));
+    src->broadcastMessage(any);
+}
+
 API_EXPORT int API_CALL mk_media_source_close(const mk_media_source ctx,int force){
     assert(ctx);
     MediaSource *src = (MediaSource *)ctx;