WinRT: added support for the SDL_loadso APIs, via LoadPackagedLibrary

VisualC/SDL/SDL_VS2012_WinRT.vcxproj

@@ -53,6 +53,7 @@
       <CompileAsWinRT Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</CompileAsWinRT>
       <CompileAsWinRT Condition="'$(Configuration)|$(Platform)'=='Release|x64'">true</CompileAsWinRT>
     </ClCompile>
+    <ClCompile Include="..\..\src\core\windows\SDL_windows.c" />
     <ClCompile Include="..\..\src\cpuinfo\SDL_cpuinfo.c" />
     <ClCompile Include="..\..\src\events\SDL_clipboardevents.c" />
     <ClCompile Include="..\..\src\events\SDL_dropevents.c" />
@@ -68,6 +69,7 @@
     <ClCompile Include="..\..\src\haptic\SDL_haptic.c" />
     <ClCompile Include="..\..\src\joystick\dummy\SDL_sysjoystick.c" />
     <ClCompile Include="..\..\src\joystick\SDL_joystick.c" />
+    <ClCompile Include="..\..\src\loadso\windows\SDL_sysloadso.c" />
     <ClCompile Include="..\..\src\render\SDL_render.c" />
     <ClCompile Include="..\..\src\render\SDL_yuv_mmx.c" />
     <ClCompile Include="..\..\src\render\SDL_yuv_sw.c" />

include/SDL_config_windowsrt.h

@@ -146,9 +146,7 @@ typedef unsigned int uintptr_t;
 #define SDL_JOYSTICK_DISABLED	1
 
 /* Enable various shared object loading systems */
-// TODO, WinRT: adapt the Win32 shared object loading code for WinRT 
-#define SDL_LOADSO_DISABLED 1
-//#define SDL_LOADSO_WINDOWS	1
+#define SDL_LOADSO_WINDOWS	1
 
 /* Enable various threading systems */
 #define SDL_THREAD_STDCPP   1

src/core/windows/SDL_windows.c

@@ -20,12 +20,12 @@
 */
 #include "SDL_config.h"
 
-#ifdef __WIN32__
+#if defined(__WIN32__) || defined(__WINRT__)
 
 #include "SDL_error.h"
 #include "SDL_windows.h"
 
-#include <objbase.h>  /* for CoInitialize/CoUninitialize */
+#include <objbase.h>  /* for CoInitialize/CoUninitialize (Win32 only) */
 
 
 /* Sets an error message based on GetLastError() */
@@ -44,6 +44,14 @@ WIN_SetError(const char *prefix)
 HRESULT
 WIN_CoInitialize(void)
 {
+#ifdef __WINRT__
+    /* DLudwig: On WinRT, it is assumed that COM was initialized in main().
+       CoInitializeEx is available (not CoInitialize though), however
+       on WinRT, main() is typically declared with the [MTAThread]
+       attribute, which, AFAIK, should initialize COM.
+    */
+    return S_OK;
+#else
     const HRESULT hr = CoInitialize(NULL);
 
     /* S_FALSE means success, but someone else already initialized. */
@@ -53,12 +61,15 @@ WIN_CoInitialize(void)
     }
 
     return hr;
+#endif
 }
 
 void
 WIN_CoUninitialize(void)
 {
+#ifndef __WINRT__
     CoUninitialize();
+#endif
 }
 
 #endif /* __WIN32__ */

src/loadso/windows/SDL_sysloadso.c

@@ -33,7 +33,15 @@ void *
 SDL_LoadObject(const char *sofile)
 {
     LPTSTR tstr = WIN_UTF8ToString(sofile);
+#ifdef __WINRT__
+    /* WinRT only publically supports LoadPackagedLibrary() for loading .dll
+       files.  LoadLibrary() is a private API, and not available for apps
+       (that can be published to MS' Windows Store.)
+    */
+    void *handle = (void *) LoadPackagedLibrary(tstr, 0);
+#else
     void *handle = (void *) LoadLibrary(tstr);
+#endif
     SDL_free(tstr);
 
     /* Generate an error message if all loads failed */