From 09092f7ac45dc6fdfdc9358feca1ca4cfe6f2fb7 Mon Sep 17 00:00:00 2001
From: Jesse Barnes <jbarnes@virtuousgeek.org>
Date: Tue, 23 Mar 2010 09:47:08 -0700
Subject: [PATCH] GLX/DRI2: only expose swap control extensions if DDX support is present

Export DDX swap control status from the DRI2 module and check for it in
GLX when initializing extensions.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---
 glx/glxdri2.c          |   23 +++++++++--------------
 hw/xfree86/dri2/dri2.c |    8 ++++++++
 hw/xfree86/dri2/dri2.h |    2 ++
 3 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/glx/glxdri2.c b/glx/glxdri2.c
index edd29b0..e791bf6 100644
--- a/glx/glxdri2.c
+++ b/glx/glxdri2.c
@@ -616,6 +616,7 @@ glxDRILeaveVT (int index, int flags)
 static void
 initializeExtensions(__GLXDRIscreen *screen)
 {
+    ScreenPtr pScreen = screen->base.pScreen;
     const __DRIextension **extensions;
     int i;
 
@@ -625,10 +626,17 @@ initializeExtensions(__GLXDRIscreen *screen)
 			 "GLX_MESA_copy_sub_buffer");
     LogMessage(X_INFO, "AIGLX: enabled GLX_MESA_copy_sub_buffer\n");
 
-    /* FIXME: only if DDX supports it */
     __glXEnableExtension(screen->glx_enable_bits, "GLX_INTEL_swap_event");
     LogMessage(X_INFO, "AIGLX: enabled GLX_INTEL_swap_event\n");
 
+    if (DRI2HasSwapControl(pScreen)) {
+	__glXEnableExtension(screen->glx_enable_bits,
+			     "GLX_SGI_swap_control");
+	__glXEnableExtension(screen->glx_enable_bits,
+			     "GLX_MESA_swap_control");
+	LogMessage(X_INFO, "AIGLX: enabled GLX_SGI_swap_control and GLX_MESA_swap_control\n");
+    }
+
     for (i = 0; extensions[i]; i++) {
 #ifdef __DRI_READ_DRAWABLE
 	if (strcmp(extensions[i]->name, __DRI_READ_DRAWABLE) == 0) {
@@ -639,19 +647,6 @@ initializeExtensions(__GLXDRIscreen *screen)
 	}
 #endif
 
-#ifdef __DRI_SWAP_CONTROL
-	if (strcmp(extensions[i]->name, __DRI_SWAP_CONTROL) == 0) {
-	    screen->swapControl =
-		(const __DRIswapControlExtension *) extensions[i];
-	    __glXEnableExtension(screen->glx_enable_bits,
-				 "GLX_SGI_swap_control");
-	    __glXEnableExtension(screen->glx_enable_bits,
-				 "GLX_MESA_swap_control");
-	    
-	    LogMessage(X_INFO, "AIGLX: enabled GLX_SGI_swap_control and GLX_MESA_swap_control\n");
-	}
-#endif
-
 #ifdef __DRI_TEX_BUFFER
 	if (strcmp(extensions[i]->name, __DRI_TEX_BUFFER) == 0) {
 	    screen->texBuffer =
diff --git a/hw/xfree86/dri2/dri2.c b/hw/xfree86/dri2/dri2.c
index 8b4c36f..2bdb733 100644
--- a/hw/xfree86/dri2/dri2.c
+++ b/hw/xfree86/dri2/dri2.c
@@ -831,6 +831,14 @@ DRI2DestroyDrawable(DrawablePtr pDraw)
 }
 
 Bool
+DRI2HasSwapControl(ScreenPtr pScreen)
+{
+    DRI2ScreenPtr ds = DRI2GetScreen(pScreen);
+
+    return (ds->ScheduleSwap && ds->GetMSC);
+}
+
+Bool
 DRI2Connect(ScreenPtr pScreen, unsigned int driverType, int *fd,
 	    const char **driverName, const char **deviceName)
 {
diff --git a/hw/xfree86/dri2/dri2.h b/hw/xfree86/dri2/dri2.h
index e1881ba..ce8a5df 100644
--- a/hw/xfree86/dri2/dri2.h
+++ b/hw/xfree86/dri2/dri2.h
@@ -188,6 +188,8 @@ extern _X_EXPORT Bool DRI2ScreenInit(ScreenPtr	pScreen,
 
 extern _X_EXPORT void DRI2CloseScreen(ScreenPtr pScreen);
 
+extern _X_EXPORT Bool DRI2HasSwapControl(ScreenPtr pScreen);
+
 extern _X_EXPORT Bool DRI2Connect(ScreenPtr pScreen,
 		 unsigned int driverType,
 		 int *fd,
-- 
1.6.6.1