Add support for the in-progress ALC_EXT_thread_local_context extension

Alc/ALc.c

@@ -111,6 +111,10 @@ static ALCfunction  alcFunctions[] = {
     { "alcCaptureStart",            (ALvoid *) alcCaptureStart          },
     { "alcCaptureStop",             (ALvoid *) alcCaptureStop           },
     { "alcCaptureSamples",          (ALvoid *) alcCaptureSamples        },
+
+    { "alcMakeCurrent",             (ALvoid *) alcMakeCurrent           },
+    { "alcGetThreadContext",        (ALvoid *) alcGetThreadContext      },
+
     { NULL,                         (ALvoid *) NULL                     }
 };
 
@@ -175,7 +179,7 @@ static ALCchar *alcDefaultAllDeviceSpecifier;
 static ALCchar *alcCaptureDefaultDeviceSpecifier;
 
 
-static ALCchar alcExtensionList[] = "ALC_ENUMERATE_ALL_EXT ALC_ENUMERATION_EXT ALC_EXT_CAPTURE ALC_EXT_disconnect ALC_EXT_EFX";
+static ALCchar alcExtensionList[] = "ALC_ENUMERATE_ALL_EXT ALC_ENUMERATION_EXT ALC_EXT_CAPTURE ALC_EXT_disconnect ALC_EXT_EFX ALC_EXTX_thread_local_context";
 static ALCint alcMajorVersion = 1;
 static ALCint alcMinorVersion = 1;
 
@@ -197,6 +201,9 @@ static CRITICAL_SECTION g_csMutex;
 static ALCcontext *g_pContextList = NULL;
 static ALCuint     g_ulContextCount = 0;
 
+// Thread-local current context
+static tls_type LocalContext;
+
 // Context Error
 static ALCenum g_eLastContextError = ALC_NO_ERROR;
 
@@ -229,6 +236,8 @@ BOOL APIENTRY DllMain(HANDLE hModule,DWORD ul_reason_for_call,LPVOID lpReserved)
             for(i = 0;BackendList[i].Deinit;i++)
                 BackendList[i].Deinit();
 
+            tls_delete(LocalContext);
+
             FreeALConfig();
             ALTHUNK_EXIT();
             DeleteCriticalSection(&g_csMutex);
@@ -252,6 +261,8 @@ static void my_deinit()
     for(i = 0;BackendList[i].Deinit;i++)
         BackendList[i].Deinit();
 
+    tls_delete(LocalContext);
+
     FreeALConfig();
     ALTHUNK_EXIT();
     DeleteCriticalSection(&g_csMutex);
@@ -305,6 +316,8 @@ static void InitAL(void)
         ALTHUNK_INIT();
         ReadALConfig();
 
+        tls_create(&LocalContext);
+
         devs = GetConfigValue(NULL, "drivers", "");
         if(devs[0])
         {
@@ -509,10 +522,18 @@ ALCcontext *GetContextSuspended(void)
 
     SuspendContext(NULL);
 
-    pContext = g_pContextList;
-    while(pContext && !pContext->InUse)
-        pContext = pContext->next;
-
+    pContext = tls_get(LocalContext);
+    if(pContext && !IsContext(pContext))
+    {
+        tls_set(LocalContext, NULL);
+        pContext = NULL;
+    }
+    if(!pContext)
+    {
+        pContext = g_pContextList;
+        while(pContext && !pContext->InUse)
+            pContext = pContext->next;
+    }
     if(pContext)
         SuspendContext(pContext);
 
@@ -1306,6 +1327,21 @@ ALCAPI ALCvoid ALCAPIENTRY alcDestroyContext(ALCcontext *context)
     Returns the currently active Context
 */
 ALCAPI ALCcontext * ALCAPIENTRY alcGetCurrentContext(ALCvoid)
+{
+    ALCcontext *pContext;
+
+    if((pContext=GetContextSuspended()) != NULL)
+        ProcessContext(pContext);
+
+    return pContext;
+}
+
+/*
+    alcGetThreadContext
+
+    Returns the currently active thread-local Context
+*/
+ALCcontext * ALCAPIENTRY alcGetThreadContext(void)
 {
     ALCcontext *pContext = NULL;
 
@@ -1313,9 +1349,12 @@ ALCAPI ALCcontext * ALCAPIENTRY alcGetCurrentContext(ALCvoid)
 
     SuspendContext(NULL);
 
-    pContext = g_pContextList;
-    while ((pContext) && (!pContext->InUse))
-        pContext = pContext->next;
+    pContext = tls_get(LocalContext);
+    if(pContext && !IsContext(pContext))
+    {
+        tls_set(LocalContext, NULL);
+        pContext = NULL;
+    }
 
     ProcessContext(NULL);
 
@@ -1374,6 +1413,8 @@ ALCAPI ALCboolean ALCAPIENTRY alcMakeContextCurrent(ALCcontext *context)
             ALContext->InUse=AL_TRUE;
             ProcessContext(ALContext);
         }
+
+        tls_set(LocalContext, NULL);
     }
     else
     {
@@ -1386,6 +1427,33 @@ ALCAPI ALCboolean ALCAPIENTRY alcMakeContextCurrent(ALCcontext *context)
     return bReturn;
 }
 
+/*
+    alcMakeCurrent
+
+    Makes the given Context the active Context for the current thread
+*/
+ALCboolean ALCAPIENTRY alcMakeCurrent(ALCcontext *context)
+{
+    ALboolean bReturn = AL_TRUE;
+
+    InitAL();
+
+    SuspendContext(NULL);
+
+    // context must be a valid Context or NULL
+    if(context == NULL || IsContext(context))
+        tls_set(LocalContext, context);
+    else
+    {
+        SetALCError(ALC_INVALID_CONTEXT);
+        bReturn = AL_FALSE;
+    }
+
+    ProcessContext(NULL);
+
+    return bReturn;
+}
+
 
 static ALenum GetFormatFromString(const char *str)
 {

OpenAL32/Include/alMain.h

@@ -20,6 +20,12 @@
 #endif
 #include <windows.h>
 
+typedef DWORD tls_type;
+#define tls_create(x) (*(x) = TlsAlloc())
+#define tls_delete(x) TlsFree((x))
+#define tls_get(x) TlsGetValue((x))
+#define tls_set(x, a) TlsSetValue((x), (a))
+
 #else
 
 #include <assert.h>
@@ -33,6 +39,12 @@
 
 #define IsBadWritePtr(a,b) (0)
 
+typedef pthread_key_t tls_type;
+#define tls_create(x) pthread_key_create((x), NULL)
+#define tls_delete(x) pthread_key_delete((x))
+#define tls_get(x) pthread_getspecific((x))
+#define tls_set(x, a) pthread_setspecific((x), (a))
+
 typedef pthread_mutex_t CRITICAL_SECTION;
 static inline void EnterCriticalSection(CRITICAL_SECTION *cs)
 {
@@ -314,6 +326,9 @@ const char *GetConfigValue(const char *blockName, const char *keyName, const cha
 int GetConfigValueInt(const char *blockName, const char *keyName, int def);
 float GetConfigValueFloat(const char *blockName, const char *keyName, float def);
 
+ALCboolean  ALCAPIENTRY alcMakeCurrent(ALCcontext *context);
+ALCcontext* ALCAPIENTRY alcGetThreadContext(void);
+
 #ifdef __cplusplus
 }
 #endif

include/AL/alext.h

@@ -144,6 +144,12 @@ typedef ALvoid (AL_APIENTRY*PFNALUNMAPDATABUFFEREXTPROC)(ALuint uiBuffer);
 #define ALC_CONNECTED                            0x313
 #endif
 
+#ifndef ALC_EXT_thread_local_context
+#define ALC_EXT_thread_local_context 1
+typedef ALCboolean (ALCAPIENTRY*PFNALCMAKECURRENTPROC)(ALCcontext *context);
+typedef ALCcontext* (ALCAPIENTRY*PFNALCGETTHREADCONTEXTPROC)(void);
+#endif
+
 #ifdef __cplusplus
 }
 #endif