Add callback on chat room subject change.

include/linphone/api/c-callbacks.h

@@ -183,6 +183,13 @@ typedef void (*LinphoneChatRoomCbsParticipantAdminStatusChangedCb) (LinphoneChat
  */
 typedef void (*LinphoneChatRoomCbsStateChangedCb) (LinphoneChatRoom *cr, LinphoneChatRoomState newState);
 
+/**
+ * Callback used to notify that the subject of a chat room has changed.
+ * @param[in] cr #LinphoneChatRoom object
+ * @param[in] subject The new subject of the chat room
+ */
+typedef void (*LinphoneChatRoomCbsSubjectChangedCb) (LinphoneChatRoom *cr, const char *subject);
+
 /**
  * Callback used to notify a chat room that a message has been received but we were unable to decrypt it
  * @param cr #LinphoneChatRoom involved in this conversation

include/linphone/api/c-chat-room-cbs.h

@@ -144,6 +144,20 @@ LINPHONE_PUBLIC LinphoneChatRoomCbsStateChangedCb linphone_chat_room_cbs_get_sta
  */
 LINPHONE_PUBLIC void linphone_chat_room_cbs_set_state_changed (LinphoneChatRoomCbs *cbs, LinphoneChatRoomCbsStateChangedCb cb);
 
+/**
+ * Get the subject changed callback.
+ * @param[in] cbs LinphoneChatRoomCbs object.
+ * @return The current subject changed callback.
+ */
+LINPHONE_PUBLIC LinphoneChatRoomCbsSubjectChangedCb linphone_chat_room_cbs_get_subject_changed (const LinphoneChatRoomCbs *cbs);
+
+/**
+ * Set the subject changed callback.
+ * @param[in] cbs LinphoneChatRoomCbs object.
+ * @param[in] cb The subject changed callback to be used.
+ */
+LINPHONE_PUBLIC void linphone_chat_room_cbs_set_subject_changed (LinphoneChatRoomCbs *cbs, LinphoneChatRoomCbsSubjectChangedCb cb);
+
 /**
  * Get the undecryptable message received callback.
  * @param[in] cbs LinphoneChatRoomCbs object.

src/c-wrapper/api/c-chat-room-cbs.cpp

@@ -31,6 +31,7 @@ struct _LinphoneChatRoomCbs {
 	LinphoneChatRoomCbsParticipantRemovedCb participantRemovedCb;
 	LinphoneChatRoomCbsParticipantAdminStatusChangedCb participantAdminStatusChangedCb;
 	LinphoneChatRoomCbsStateChangedCb stateChangedCb;
+	LinphoneChatRoomCbsSubjectChangedCb subjectChangedCb;
 	LinphoneChatRoomCbsUndecryptableMessageReceivedCb undecryptableMessageReceivedCb;
 };
 
@@ -116,6 +117,14 @@ void linphone_chat_room_cbs_set_state_changed (LinphoneChatRoomCbs *cbs, Linphon
 	cbs->stateChangedCb = cb;
 }
 
+LinphoneChatRoomCbsSubjectChangedCb linphone_chat_room_cbs_get_subject_changed (const LinphoneChatRoomCbs *cbs) {
+	return cbs->subjectChangedCb;
+}
+
+void linphone_chat_room_cbs_set_subject_changed (LinphoneChatRoomCbs *cbs, LinphoneChatRoomCbsSubjectChangedCb cb) {
+	cbs->subjectChangedCb = cb;
+}
+
 LinphoneChatRoomCbsUndecryptableMessageReceivedCb linphone_chat_room_cbs_get_undecryptable_message_received (const LinphoneChatRoomCbs *cbs) {
 	return cbs->undecryptableMessageReceivedCb;
 }

src/chat/client-group-chat-room.cpp

@@ -184,6 +184,15 @@ void ClientGroupChatRoom::onParticipantSetAdmin (const Address &addr, bool isAdm
 		cb(cr, L_GET_C_BACK_PTR(participant), isAdmin);
 }
 
+void ClientGroupChatRoom::onSubjectChanged (const std::string &subject) {
+	this->subject = subject;
+	LinphoneChatRoom *cr = L_GET_C_BACK_PTR(this);
+	LinphoneChatRoomCbs *cbs = linphone_chat_room_get_callbacks(cr);
+	LinphoneChatRoomCbsSubjectChangedCb cb = linphone_chat_room_cbs_get_subject_changed(cbs);
+	if (cb)
+		cb(cr, subject.c_str());
+}
+
 // -----------------------------------------------------------------------------
 
 void ClientGroupChatRoom::onCallSessionStateChanged (const CallSession &session, LinphoneCallState state, const string &message) {

src/chat/client-group-chat-room.h

@@ -59,6 +59,7 @@ private:
 	void onParticipantAdded (const Address &addr) override;
 	void onParticipantRemoved (const Address &addr) override;
 	void onParticipantSetAdmin (const Address &addr, bool isAdmin) override;
+	void onSubjectChanged (const std::string &subject) override;
 
 private:
 	/* CallSessionListener */

src/conference/conference-listener.h

@@ -32,6 +32,7 @@ public:
 	virtual void onParticipantAdded (const Address &addr) = 0;
 	virtual void onParticipantRemoved (const Address &addr) = 0;
 	virtual void onParticipantSetAdmin (const Address &addr, bool isAdmin) = 0;
+	virtual void onSubjectChanged (const std::string &subject) = 0;
 };
 
 LINPHONE_END_NAMESPACE

src/conference/remote-conference.cpp

@@ -92,4 +92,6 @@ void RemoteConference::onParticipantRemoved (const Address &addr) {}
 
 void RemoteConference::onParticipantSetAdmin (const Address &addr, bool isAdmin) {}
 
+void RemoteConference::onSubjectChanged (const std::string &subject) {}
+
 LINPHONE_END_NAMESPACE

src/conference/remote-conference.h

@@ -48,6 +48,7 @@ protected:
 	void onParticipantAdded (const Address &addr) override;
 	void onParticipantRemoved (const Address &addr) override;
 	void onParticipantSetAdmin (const Address &addr, bool isAdmin) override;
+	void onSubjectChanged (const std::string &subject) override;
 
 protected:
 	RemoteConferenceEventHandler *eventHandler = nullptr;