Adding ref_count in structure MSFactory to keep track of users through initializations.

Modifying ms_factory_destroy to destroy it and its contents when no one is using it anymore.
Modifying ms_factory_uninit to destroy the card manager and webcam manager when there is
 no  references to them.

include/mediastreamer2/msfactory.h

@@ -42,6 +42,7 @@ struct _MSFactory{
 	int mtu;
 	bool_t statistics_enabled;
 	bool_t voip_initd;
+	int ref_count;
 };
 
 typedef struct _MSFactory MSFactory;
@@ -80,6 +81,12 @@ LINPHONE_DEPRECATED MS2_PUBLIC MSFactory *ms_factory_get_fallback(void);
 **/
 MS2_PUBLIC void ms_factory_destroy(MSFactory *factory);
 
+/**
+ * Exits the factory : unset voip and destroys the factory if there is no references to it.
+ * Ensures it can be destroyed before destroying all objects created by the factory.
+ **/
+MS2_PUBLIC MSFactory* ms_factory_exit(MSFactory* factory);
+
 MS2_PUBLIC void ms_factory_register_filter(MSFactory *factory, MSFilterDesc *desc);
 
 /**

src/base/msfactory.c

@@ -240,27 +240,39 @@ MSFactory *ms_factory_new(void){
 	return obj;
 }
 
+
 /**
  * Destroy the factory.
  * This should be done after destroying all objects created by the factory.
 **/
 void ms_factory_destroy(MSFactory *factory){
-	ms_factory_uninit_plugins(factory);
-	//if (factory->evq) ms_event_queue_destroy(factory->evq, factory);
-	if (factory->evq) ms_factory_destroy_event_queue(factory);
-	factory->formats=ms_list_free_with_data(factory->formats,(void(*)(void*))ms_fmt_descriptor_destroy);
-	factory->desc_list=ms_list_free(factory->desc_list);
-	ms_list_for_each(factory->stats_list,ms_free);
-	factory->stats_list=ms_list_free(factory->stats_list);
-	factory->offer_answer_provider_list = ms_list_free(factory->offer_answer_provider_list);
-	ms_list_for_each(factory->platform_tags, ms_free);
-	factory->platform_tags = ms_list_free(factory->platform_tags);
-	if (factory->plugins_dir) ms_free(factory->plugins_dir);
-	ms_free(factory);
+	factory->ref_count--;
+	if (factory->ref_count == 0){
+		ms_factory_uninit_plugins(factory);
+		//if (factory->evq) ms_event_queue_destroy(factory->evq, factory);
+		if (factory->evq) ms_factory_destroy_event_queue(factory);
+		factory->formats=ms_list_free_with_data(factory->formats,(void(*)(void*))ms_fmt_descriptor_destroy);
+		factory->desc_list=ms_list_free(factory->desc_list);
+		ms_list_for_each(factory->stats_list,ms_free);
+		factory->stats_list=ms_list_free(factory->stats_list);
+		factory->offer_answer_provider_list = ms_list_free(factory->offer_answer_provider_list);
+		ms_list_for_each(factory->platform_tags, ms_free);
+		factory->platform_tags = ms_list_free(factory->platform_tags);
+		if (factory->plugins_dir) ms_free(factory->plugins_dir);
+		ms_free(factory);
+	}
+
 	//if (factory==fallback_factory) fallback_factory=NULL;
 }
-
-
+//
+//MSFactory* ms_factory_exit(MSFactory* factory){
+//	ms_factory_uninit_voip(factory);
+//
+//		ms_factory_destroy(factory);
+//		return NULL;
+//	}
+//	return factory;
+//}
 
 void ms_factory_register_filter(MSFactory* factory, MSFilterDesc* desc ) {
 	if (desc->id==MS_FILTER_NOT_SET_ID){

src/voip/msvoip.c

@@ -265,7 +265,7 @@ void ms_factory_init_voip(MSFactory *obj){
 	int i;
 	
 	ms_srtp_init();
-	
+	obj->ref_count++;
 	/* register builtin VoIP MSFilter's */
 	for (i=0;ms_voip_filter_descs[i]!=NULL;i++){
 		ms_factory_register_filter(obj,ms_voip_filter_descs[i]);
@@ -323,19 +323,21 @@ void ms_factory_init_voip(MSFactory *obj){
 
 void ms_factory_uninit_voip(MSFactory *obj){
 	ms_srtp_shutdown();
-	if (obj->voip_initd){
+	managers_ref--;
+	if (managers_ref==0){
+		ms_snd_card_manager_destroy();
 #ifdef VIDEO_ENABLED
-		ms_video_presets_manager_destroy(obj->video_presets_manager);
+		ms_web_cam_manager_destroy();
 #endif
-		managers_ref--;
-		if (managers_ref==0){
-			ms_snd_card_manager_destroy();
+	if (obj->voip_initd){
 #ifdef VIDEO_ENABLED
-			ms_web_cam_manager_destroy();
+		ms_video_presets_manager_destroy(obj->video_presets_manager);
 #endif
+
 		}
+		obj->voip_initd = FALSE;
 	}
-	obj->voip_initd = FALSE;
+	
 }
 
 void ms_voip_exit(){