Add reference counting to the ALC contexts

2 files changed, 65 insertions, 25 deletions

diff --git a/Alc/ALc.c b/Alc/ALc.c
index 0cca6026..d7ddc15c 100644
--- a/Alc/ALc.c
+++ b/Alc/ALc.c
@@ -1361,11 +1361,41 @@ static ALvoid InitContext(ALCcontext *pContext)
 */
 static ALCvoid FreeContext(ALCcontext *context)
 {
+    LockLists();
+    if(context == GlobalContext)
+        GlobalContext = NULL;
+    UnlockLists();
+
+    if(context->SourceMap.size > 0)
+    {
+        ERR("FreeContext(%p): deleting %d Source(s)\n", context, context->SourceMap.size);
+        ReleaseALSources(context);
+    }
+    ResetUIntMap(&context->SourceMap);
+
+    if(context->EffectSlotMap.size > 0)
+    {
+        ERR("FreeContext(%p): deleting %d AuxiliaryEffectSlot(s)\n", context, context->EffectSlotMap.size);
+        ReleaseALAuxiliaryEffectSlots(context);
+    }
+    ResetUIntMap(&context->EffectSlotMap);
+
+    free(context->ActiveSources);
+    context->ActiveSources = NULL;
+    context->MaxActiveSources = 0;
+    context->ActiveSourceCount = 0;
+
     //Invalidate context
     memset(context, 0, sizeof(ALCcontext));
     free(context);
 }
 
+static void ALCcontext_Deref(ALCcontext *context)
+{
+    if(DecrementRef(&context->ref) == 0)
+        FreeContext(context);
+}
+
 ///////////////////////////////////////////////////////
 
 
@@ -1998,6 +2028,8 @@ ALC_API ALCcontext* ALC_APIENTRY alcCreateContext(ALCdevice *device, const ALCin
         ALContext = calloc(1, sizeof(ALCcontext));
         if(ALContext)
         {
+            ALContext->ref = 1;
+
             ALContext->MaxActiveSources = 256;
             ALContext->ActiveSources = malloc(sizeof(ALContext->ActiveSources[0]) *
                                               ALContext->MaxActiveSources);
@@ -2059,11 +2091,6 @@ ALC_API ALCvoid ALC_APIENTRY alcDestroyContext(ALCcontext *context)
     *list = (*list)->next;
     g_ulContextCount--;
 
-    if(context == tls_get(LocalContext))
-        tls_set(LocalContext, NULL);
-    if(context == GlobalContext)
-        GlobalContext = NULL;
-
     Device = context->Device;
     LockDevice(Device);
     for(i = 0;i < Device->NumContexts;i++)
@@ -2084,26 +2111,7 @@ ALC_API ALCvoid ALC_APIENTRY alcDestroyContext(ALCcontext *context)
     }
     UnlockLists();
 
-    if(context->SourceMap.size > 0)
-    {
-        ERR("alcDestroyContext(): deleting %d Source(s)\n", context->SourceMap.size);
-        ReleaseALSources(context);
-    }
-    ResetUIntMap(&context->SourceMap);
-
-    if(context->EffectSlotMap.size > 0)
-    {
-        ERR("alcDestroyContext(): deleting %d AuxiliaryEffectSlot(s)\n", context->EffectSlotMap.size);
-        ReleaseALAuxiliaryEffectSlots(context);
-    }
-    ResetUIntMap(&context->EffectSlotMap);
-
-    free(context->ActiveSources);
-    context->ActiveSources = NULL;
-    context->MaxActiveSources = 0;
-    context->ActiveSourceCount = 0;
-
-    FreeContext(context);
+    ALCcontext_Deref(context);
 }
 
 
diff --git a/OpenAL32/Include/alMain.h b/OpenAL32/Include/alMain.h
index 2f30a953..0a006ee9 100644
--- a/OpenAL32/Include/alMain.h
+++ b/OpenAL32/Include/alMain.h
@@ -229,6 +229,36 @@ void *GetSymbol(void *handle, const char *name);
 
 #endif
 
+#ifdef __GNUC__
+typedef ALuint RefCount;
+static __inline RefCount IncrementRef(volatile RefCount *ptr)
+{ return __sync_add_and_fetch(ptr, 1); }
+static __inline RefCount DecrementRef(volatile RefCount *ptr)
+{ return __sync_sub_and_fetch(ptr, 1); }
+
+#elif defined(_WIN32)
+
+typedef LONG RefCount;
+static __inline RefCount IncrementRef(volatile RefCount *ptr)
+{ return InterlockedInrement(ptr); }
+static __inline RefCount DecrementRef(volatile RefCount *ptr)
+{ return InterlockedDecrement(ptr); }
+
+#elif defined(__APPLE__)
+
+#include <libkern/OSAtomic.h>
+
+typedef int32_t RefCount;
+static __inline RefCount IncrementRef(volatile RefCount *ptr)
+{ return OSAtomicIncrement32Barrier(ptr); }
+static __inline RefCount DecrementRef(volatile RefCount *ptr)
+{ return OSAtomicDecrement32Barrier(ptr); }
+
+#else
+#error "No atomic functions available on this platform!"
+#endif
+
+
 #include "alListener.h"
 #include "alu.h"
 
@@ -477,6 +507,8 @@ struct ALCdevice_struct
 
 struct ALCcontext_struct
 {
+    volatile RefCount ref;
+
     ALlistener  Listener;
 
     UIntMap SourceMap;