Remove screenConfigs from __DRIscreen.

The screenConfigs field of __DRIscreen points back to the containing
__GLXscreenConfigs struct.  This is a serious abstraction violation; it
assumes that the loader is libGL and that there *is* a __GLXscreenConfigs
type in the loader.

Using the containerOf macro, we can get from the __DRIscreen pointer to
the containing __GLXscreenConfigs struct, at a place in the stack
where the above is a valid assumption.  Besides, the __DRI* structs shouldn't
hold state other than the private pointer.

3 files changed, 14 insertions, 3 deletions

diff --git a/src/glx/x11/glxext.c b/src/glx/x11/glxext.c
index 85c990d4fc..45b1dde91b 100644
--- a/src/glx/x11/glxext.c
+++ b/src/glx/x11/glxext.c
@@ -1203,7 +1203,6 @@ static Bool AllocAndFetchScreenConfigs(Display *dpy, __GLXdisplayPrivate *priv)
 	    if (priv->driDisplay.createNewScreen &&
 		priv->driDisplay.createNewScreen[i]) {
 
-		psc->driScreen.screenConfigs = (void *)psc;
 		psc->driScreen.private =
 		    CallCreateNewScreen(dpy, i, psc,
 					& priv->driDisplay,
diff --git a/src/glx/x11/glxextensions.c b/src/glx/x11/glxextensions.c
index 1d99b61db0..96964d1db1 100644
--- a/src/glx/x11/glxextensions.c
+++ b/src/glx/x11/glxextensions.c
@@ -356,6 +356,7 @@ __glXProcessServerString( const struct extension_info * ext,
    }
 }
 
+#ifdef GLX_DIRECT_RENDERING
 
 /**
  * Enable a named GLX extension on a given screen.
@@ -370,14 +371,18 @@ __glXProcessServerString( const struct extension_info * ext,
  * \since Internal API version 20030813.
  */
 void
-__glXScrEnableExtension( __GLXscreenConfigs *psc, const char * name )
+__glXScrEnableExtension( __DRIscreen *driScreen, const char * name )
 {
+    __GLXscreenConfigs *psc =
+	containerOf(driScreen, __GLXscreenConfigs, driScreen);
+
    __glXExtensionsCtr();
    __glXExtensionsCtrScreen(psc);
    set_glx_extension( known_glx_extensions, name, strlen( name ), GL_TRUE,
 		      psc->direct_support );
 }
 
+#endif
 
 /**
  * Initialize global extension support tables.
diff --git a/src/glx/x11/glxextensions.h b/src/glx/x11/glxextensions.h
index a4241b6b7f..62bbf116e9 100644
--- a/src/glx/x11/glxextensions.h
+++ b/src/glx/x11/glxextensions.h
@@ -234,7 +234,14 @@ extern GLboolean __glXExtensionBitIsEnabled( struct __GLXscreenConfigsRec *psc,
 extern const char * __glXGetClientExtensions( void );
 extern void __glXCalculateUsableExtensions( struct __GLXscreenConfigsRec *psc,
     GLboolean display_is_direct_capable, int server_minor_version );
-extern void __glXScrEnableExtension( struct __GLXscreenConfigsRec *psc, const char * name );
+
+#ifdef GLX_DIRECT_RENDERING
+
+struct __DRIscreenRec;
+extern void __glXScrEnableExtension( struct __DRIscreenRec *driScreen, const char * name );
+
+#endif
+
 extern void __glXCalculateUsableGLExtensions( struct __GLXcontextRec * gc,
     const char * server_string, int major_version, int minor_version );
 extern void __glXGetGLVersion( int * major_version, int * minor_version );