Implement new screen extension API.

This new API lets the loader examine DRI level extensions provided by the
driver in a forward compatible manner.

Much of the churn in the DRI interface is adding support for new
extensions or removing old, unused extensions.  This new extension
mechanism lets the loader query the extensions provided by the driver
and implement the extensions it knows about.  Deprecating extensions
is done by not exporting that extension in the list, which doesn't
require keeping old function pointers around to preserve ABI.

2 files changed, 23 insertions, 0 deletions

diff --git a/src/glx/x11/glxext.c b/src/glx/x11/glxext.c
index ee8e238bec..cb187717f1 100644
--- a/src/glx/x11/glxext.c
+++ b/src/glx/x11/glxext.c
@@ -1011,6 +1011,18 @@ CallCreateNewScreen(Display *dpy, int scrn, __GLXscreenConfigs *psc,
 
     return psp;
 }
+
+static void queryExtensions(__GLXscreenConfigs *psc)
+{
+    const __DRIextension **extensions;
+    int i;
+
+    extensions = psc->driScreen.getExtensions(&psc->driScreen);
+    for (i = 0; extensions[i]; i++) {
+	/* Unknown extension, just ignore... */
+    }
+}
+
 #endif /* GLX_DIRECT_RENDERING */
 
 
@@ -1205,6 +1217,8 @@ static Bool AllocAndFetchScreenConfigs(Display *dpy, __GLXdisplayPrivate *priv)
 		    CallCreateNewScreen(dpy, i, psc,
 					& priv->driDisplay,
 					priv->driDisplay.createNewScreen[i] );
+		if (psc->driScreen.private != NULL)
+		    queryExtensions(psc);
 	    }
 	}
 #endif
diff --git a/src/mesa/drivers/dri/common/dri_util.c b/src/mesa/drivers/dri/common/dri_util.c
index 84a6d819de..c8be7b0706 100644
--- a/src/mesa/drivers/dri/common/dri_util.c
+++ b/src/mesa/drivers/dri/common/dri_util.c
@@ -624,6 +624,14 @@ driCreateNewContext(__DRIscreen *screen, const __GLcontextModes *modes,
 }
 /*@}*/
 
+static const __DRIextension **
+driGetExtensions(__DRIscreen *screen)
+{
+    __DRIscreenPrivate *psp = screen->private;
+    static const __DRIextension *extensions[1];
+
+    return extensions;
+}
 
 /*****************************************************************/
 /** \name Screen handling functions                              */
@@ -750,6 +758,7 @@ void * __DRI_CREATE_NEW_SCREEN( int scrn, __DRIscreen *psc,
     psp->dummyContextPriv.driScreenPriv = NULL;
 
     psc->destroyScreen     = driDestroyScreen;
+    psc->getExtensions     = driGetExtensions;
     psc->createNewDrawable = driCreateNewDrawable;
     psc->getMSC            = driGetMSC;
     psc->createNewContext  = driCreateNewContext;