From c9665c24d178c33a4736f90e68c8ca0f2350024e Mon Sep 17 00:00:00 2001
From: "Steinar H. Gunderson" <steinar+vlc@gunderson.no>
Date: Tue, 28 Sep 2010 00:07:02 +0200
Subject: [PATCH] Make AddRef() and Release() atomic.

---
 modules/access/sdi.cpp | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/modules/access/sdi.cpp b/modules/access/sdi.cpp
index ec93c27cf6..9c6946e950 100644
--- a/modules/access/sdi.cpp
+++ b/modules/access/sdi.cpp
@@ -16,6 +16,7 @@
 #include <vlc_picture.h>
 #include <vlc_charset.h>
 #include <vlc_fs.h>
+#include <vlc_atomic.h>
 
 #include <arpa/inet.h>
 
@@ -126,32 +127,31 @@ struct demux_sys_t
 class DeckLinkCaptureDelegate : public IDeckLinkInputCallback
 {
 public:
-    DeckLinkCaptureDelegate( demux_t *p_demux ) : m_ref_(1), p_demux_(p_demux) {}
+    DeckLinkCaptureDelegate( demux_t *p_demux ) : p_demux_(p_demux)
+    {
+        vlc_atomic_set( &m_ref_, 1 );
+    }
 
     virtual HRESULT STDMETHODCALLTYPE QueryInterface(REFIID iid, LPVOID *ppv) { return E_NOINTERFACE; }
 
-    /* Note: AddRef() and Release() here are not thread safe. */
-
     virtual ULONG STDMETHODCALLTYPE AddRef(void)
     {
-        return ++m_ref_;
+        return vlc_atomic_inc( &m_ref_ );
     }
 
     virtual ULONG STDMETHODCALLTYPE Release(void)
     {
-        if ( --m_ref_ == 0 )
-        {
+        uintptr_t new_ref = vlc_atomic_dec( &m_ref_ );
+        if ( new_ref == 0 )
             delete this;
-            return 0;
-        }
-        return m_ref_;
+        return new_ref;
     }
 
     virtual HRESULT STDMETHODCALLTYPE VideoInputFormatChanged(BMDVideoInputFormatChangedEvents, IDeckLinkDisplayMode*, BMDDetectedVideoInputFormatFlags);
     virtual HRESULT STDMETHODCALLTYPE VideoInputFrameArrived(IDeckLinkVideoInputFrame*, IDeckLinkAudioInputPacket*);
 
 private:
-    int m_ref_;
+    vlc_atomic_t m_ref_;
     demux_t *p_demux_;
 };
 
-- 
2.39.2