1 files changed, 92 insertions, 12 deletions

diff --git a/src/gallium/state_trackers/wgl/stw_ext_context.c b/src/gallium/state_trackers/wgl/stw_ext_context.c
index 4dd00bb4f94..0049896b8df 100644
--- a/src/gallium/state_trackers/wgl/stw_ext_context.c
+++ b/src/gallium/state_trackers/wgl/stw_ext_context.c
@@ -22,6 +22,8 @@
  * OTHER DEALINGS IN THE SOFTWARE.
  */
 
+#include <stdio.h>
+#include <assert.h>
 #include <windows.h>
 
 #define WGL_WGLEXT_PROTOTYPES
@@ -31,10 +33,31 @@
 
 #include "stw_icd.h"
 #include "stw_context.h"
+#include "stw_device.h"
 
+
+/**
+ * The implementation of this function is tricky.  The OPENGL32.DLL library
+ * remaps the context IDs returned by our stw_create_context_attribs()
+ * function to different values returned to the caller of wglCreateContext().
+ * That is, DHGLRC (driver) handles are not equivalent to HGLRC (public)
+ * handles.
+ *
+ * So we need to generate a new HGLRC ID here.  We do that by calling
+ * the regular wglCreateContext() function.  Then, we replace the newly-
+ * created stw_context with a new stw_context that reflects the arguments
+ * to this function.
+ */
 HGLRC WINAPI
 wglCreateContextAttribsARB(HDC hDC, HGLRC hShareContext, const int *attribList)
 {
+   typedef HGLRC (*wglCreateContext_t)(HDC hdc);
+   typedef BOOL (*wglDeleteContext_t)(HGLRC hglrc);
+   HGLRC context;
+   static HMODULE opengl_lib = 0;
+   static wglCreateContext_t wglCreateContext_func = 0;
+   static wglDeleteContext_t wglDeleteContext_func = 0;
+
    int majorVersion = 1, minorVersion = 0, layerPlane = 0;
    int contextFlags = 0x0;
    int profileMask = WGL_CONTEXT_CORE_PROFILE_BIT_ARB;
@@ -67,7 +90,7 @@ wglCreateContextAttribsARB(HDC hDC, HGLRC hShareContext, const int *attribList)
          default:
             /* bad attribute */
             SetLastError(ERROR_INVALID_PARAMETER);
-            return NULL;
+            return 0;
          }
       }
    }
@@ -77,46 +100,103 @@ wglCreateContextAttribsARB(HDC hDC, HGLRC hShareContext, const int *attribList)
    case 1:
       if (minorVersion < 0 || minorVersion > 5) {
          SetLastError(ERROR_INVALID_VERSION_ARB);
-         return NULL;
+         return 0;
       }
       break;
    case 2:
       if (minorVersion < 0 || minorVersion > 1) {
          SetLastError(ERROR_INVALID_VERSION_ARB);
-         return NULL;
+         return 0;
       }
       break;
    case 3:
       if (minorVersion < 0 || minorVersion > 3) {
          SetLastError(ERROR_INVALID_VERSION_ARB);
-         return NULL;
+         return 0;
       }
       break;
    case 4:
       if (minorVersion < 0 || minorVersion > 2) {
          SetLastError(ERROR_INVALID_VERSION_ARB);
-         return NULL;
+         return 0;
       }
       break;
    default:
-      return NULL;
+      return 0;
    }
 
    if ((contextFlags & WGL_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB) &&
        majorVersion < 3) {
       SetLastError(ERROR_INVALID_VERSION_ARB);
-      return NULL;
+      return 0;
    }
 
    /* check profileMask */
    if (profileMask != WGL_CONTEXT_CORE_PROFILE_BIT_ARB &&
        profileMask != WGL_CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB) {
       SetLastError(ERROR_INVALID_PROFILE_ARB);
-      return NULL;
+      return 0;
+   }
+
+   /* Get pointer to OPENGL32.DLL's wglCreate/DeleteContext() functions */
+   if (opengl_lib == 0) {
+      /* Open the OPENGL32.DLL library */
+      opengl_lib = LoadLibraryA("OPENGL32.DLL");
+      if (!opengl_lib) {
+         fprintf(stderr, "wgl: LoadLibrary(OPENGL32.DLL) failed\n");
+         fflush(stderr);
+         return 0;
+      }
+
+      /* Get pointer to wglCreateContext() function */
+      wglCreateContext_func = (wglCreateContext_t)
+         GetProcAddress(opengl_lib, "wglCreateContext");
+      if (!wglCreateContext_func) {
+         fprintf(stderr, "wgl: failed to get wglCreateContext()\n");
+         fflush(stderr);
+         return 0;
+      }
+
+      /* Get pointer to wglDeleteContext() function */
+      wglDeleteContext_func = (wglDeleteContext_t)
+         GetProcAddress(opengl_lib, "wglDeleteContext");
+      if (!wglDeleteContext_func) {
+         fprintf(stderr, "wgl: failed to get wglDeleteContext()\n");
+         fflush(stderr);
+         return 0;
+      }
+   }
+
+   /* Call wglCreateContext to get a valid context ID */
+   context = wglCreateContext_func(hDC);
+
+   if (context) {
+      /* Now replace the context we just created with a new one that reflects
+       * the attributes passed to this function.
+       */
+      DHGLRC dhglrc, c, share_dhglrc = 0;
+
+      /* Convert public HGLRC to driver DHGLRC */
+      if (stw_dev && stw_dev->callbacks.wglCbGetDhglrc) {
+         dhglrc = stw_dev->callbacks.wglCbGetDhglrc(context);
+         if (hShareContext)
+            share_dhglrc = stw_dev->callbacks.wglCbGetDhglrc(hShareContext);
+      }
+      else {
+         /* not using ICD */
+         dhglrc = (DHGLRC) context;
+         share_dhglrc = (DHGLRC) hShareContext;
+      }
+
+      c = stw_create_context_attribs(hDC, layerPlane, share_dhglrc,
+                                     majorVersion, minorVersion,
+                                     contextFlags, profileMask,
+                                     dhglrc);
+      if (!c) {
+         wglDeleteContext_func(context);
+         context = 0;
+      }
    }
 
-   return (HGLRC) stw_create_context_attribs(hDC, layerPlane,
-                                             (DHGLRC) (UINT_PTR) hShareContext,
-                                             majorVersion, minorVersion,
-                                             contextFlags, profileMask);
+   return context;
 }