SDL_DXGIGetOutputInfo() checks input parameters and returns a boolean value whether or not it succeeded.

include/SDL_system.h

@@ -59,7 +59,7 @@ extern DECLSPEC IDirect3DDevice9* SDLCALL SDL_RenderGetD3D9Device(SDL_Renderer *
    These can be passed to EnumAdapters and EnumOutputs respectively to get the objects
    required to create a DX10 or DX11 device and swap chain.
  */
-extern DECLSPEC void SDLCALL SDL_DXGIGetOutputInfo( int displayIndex, int *adapterIndex, int *outputIndex );
+extern DECLSPEC SDL_bool SDLCALL SDL_DXGIGetOutputInfo( int displayIndex, int *adapterIndex, int *outputIndex );
 
 #endif /* __WIN32__ */
 

src/dynapi/SDL_dynapi_procs.h

@@ -604,5 +604,5 @@ SDL_DYNAPI_PROC(SDL_bool,SDL_HasAVX,(void),(),return)
 SDL_DYNAPI_PROC(SDL_AssertionHandler,SDL_GetDefaultAssertionHandler,(void),(),return)
 SDL_DYNAPI_PROC(SDL_AssertionHandler,SDL_GetAssertionHandler,(void **a),(a),return)
 #ifdef __WIN32__
-SDL_DYNAPI_PROC(void,SDL_DXGIGetOutputInfo,(int a,int *b, int *c),(a,b,c),)
+SDL_DYNAPI_PROC(SDL_bool,SDL_DXGIGetOutputInfo,(int a,int *b, int *c),(a,b,c),return)
 #endif

src/video/windows/SDL_windowsvideo.c

@@ -253,7 +253,7 @@ SDL_bool
 DXGI_LoadDLL(void **pDXGIDLL, IDXGIFactory **pDXGIFactory)
 {
     *pDXGIDLL = SDL_LoadObject("DXGI.DLL");
-	if (*pDXGIDLL ) {
+    if (!*pDXGIDLL) {
         HRESULT (WINAPI *CreateDXGI)( REFIID riid, void **ppFactory );
 
         CreateDXGI =
@@ -279,54 +279,68 @@ DXGI_LoadDLL( void **pDXGIDLL , IDXGIFactory **pDXGIFactory )
 }
 
 
-void
+SDL_bool
 SDL_DXGIGetOutputInfo(int displayIndex, int *adapterIndex, int *outputIndex)
 {
+    SDL_DisplayData *pData = (SDL_DisplayData *)SDL_GetDisplayDriverData(displayIndex);
     void *pDXGIDLL;
     IDXGIFactory *pDXGIFactory;
+    IDXGIAdapter *pDXGIAdapter;
+    IDXGIOutput* pDXGIOutput;
+    int nAdapter = 0, nOutput = 0;
+    char *displayName;
+
+    if (!adapterIndex) {
+        SDL_InvalidParamError("adapterIndex");
+        return SDL_FALSE;
+    }
+
+    if (!outputIndex) {
+        SDL_InvalidParamError("outputIndex");
+        return SDL_FALSE;
+    }
 
     *adapterIndex = -1;
     *outputIndex = -1;
 
-	if (!DXGI_LoadDLL(&pDXGIDLL, &pDXGIFactory)) {
-		SDL_SetError("Unable to create DXGI interface");
-	} else {
-		SDL_DisplayData *pData = (SDL_DisplayData *)SDL_GetDisplayDriverData(displayIndex);
-
     if (!pData) {
         SDL_SetError("Invalid display index");
-		} else {
+        return SDL_FALSE;
-			char *displayName = WIN_StringToUTF8(pData->DeviceName);
+    }
-			int nAdapter = 0, nOutput = 0;
+
-			IDXGIAdapter* pDXGIAdapter;
+    if (!DXGI_LoadDLL(&pDXGIDLL, &pDXGIFactory)) {
-			while ( *adapterIndex == -1 && IDXGIFactory_EnumAdapters(pDXGIFactory, nAdapter, &pDXGIAdapter) != DXGI_ERROR_NOT_FOUND ) {
+        SDL_SetError("Unable to create DXGI interface");
-				IDXGIOutput* pDXGIOutput;
+        return SDL_FALSE;
-				while ( *adapterIndex == -1 && IDXGIAdapter_EnumOutputs(pDXGIAdapter, nOutput, &pDXGIOutput) != DXGI_ERROR_NOT_FOUND ) {
+    }
+
+    displayName = WIN_StringToUTF8(pData->DeviceName);
+    while (*adapterIndex == -1 && SUCCEEDED(IDXGIFactory_EnumAdapters(pDXGIFactory, nAdapter, &pDXGIAdapter))) {
+        while (*adapterIndex == -1 && SUCCEEDED(IDXGIAdapter_EnumOutputs(pDXGIAdapter, nOutput, &pDXGIOutput))) {
             DXGI_OUTPUT_DESC outputDesc;
             if (SUCCEEDED(IDXGIOutput_GetDesc(pDXGIOutput, &outputDesc))) {
                 char *outputName = WIN_StringToUTF8(outputDesc.DeviceName);
-
+                if (SDL_strcmp(outputName, displayName) == 0) {
-						if(!SDL_strcmp(outputName, displayName)) {
                     *adapterIndex = nAdapter;
                     *outputIndex = nOutput;
                 }
-
                 SDL_free( outputName );
             }
-
             IDXGIOutput_Release(pDXGIOutput);
             nOutput++;
         }
-
         IDXGIAdapter_Release(pDXGIAdapter);
         nAdapter++;
     }
     SDL_free(displayName);
-		}
 
-		/* free up the D3D stuff we inited */
+    /* free up the DXGI factory */
-		IDXGIFactory_AddRef( pDXGIFactory );
+    IDXGIFactory_Release(pDXGIFactory);
     SDL_UnloadObject(pDXGIDLL);
+
+    if (*adapterIndex == -1) {
+        return SDL_FALSE;
+    } else {
+        return SDL_TRUE;
     }
 }