[vlc-commits] cppcx: Fix a crash when releasing the EventManager

[Hugo Beauzée-Luyssen]

libvlcpp | branch: master | Hugo Beauzée-Luyssen <hugo at beauzee.fr> | Thu Jul 30 11:14:07 2015 +0200| [bd6ff48af25e7d2670b16efd31b87d0d4c3c4f65] | committer: Hugo Beauzée-Luyssen

cppcx: Fix a crash when releasing the EventManager

We don't want to hold a copy of the event manager, but rather a reference. The C++/CX type is intented to be solely a wrapper to the actual type.
Furthermore, if due to C++/CX being garbage collected, holding a copy means the EventManagerCX destructor might be called after MediaPlayerCX's destructor, since it only decreases the EventManagerCX's refcount.
Calling EventManagerCX's destructor without a valid libvlc_media_player_t (ie. VLC::MediaPlayer being deleted) will cause undefined behavior. By storing a reference, we ensure we just forward the events registrations to the actual VLC::EventManager, and that the GC won't bite us when releasing resources.

> http://git.videolan.org/gitweb.cgi/libvlcpp.git/?a=commit;h=bd6ff48af25e7d2670b16efd31b87d0d4c3c4f65
---

 cppcx/EventManagerCX.hpp |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cppcx/EventManagerCX.hpp b/cppcx/EventManagerCX.hpp
index 6683e31..b53931e 100644
--- a/cppcx/EventManagerCX.hpp
+++ b/cppcx/EventManagerCX.hpp
@@ -524,7 +524,7 @@ namespace libVLCX
         MediaPlayerEventManager(VLC::MediaPlayerEventManager& em);
 
     private:
-        VLC::MediaPlayerEventManager m_em;
+        VLC::MediaPlayerEventManager& m_em;
         std::vector<VLC::EventManager::RegisteredEvent> m_events;
     };