dri2: support glXWaitGL & glXWaitX by copying fake front to front and

vice-versa.
(cherry picked from commit 2a8b8077d8f6001eb57deba60e1009fc99c28668)

Signed-off-by: Keith Packard <keithp@keithp.com>

4 files changed, 67 insertions, 11 deletions

diff --git a/glx/glxcmds.c b/glx/glxcmds.c
index 71f15442a..ff8b126be 100644
--- a/glx/glxcmds.c
+++ b/glx/glxcmds.c
@@ -748,29 +748,46 @@ int __glXDisp_QueryVersion(__GLXclientState *cl, GLbyte *pc)
 int __glXDisp_WaitGL(__GLXclientState *cl, GLbyte *pc)
 {
     xGLXWaitGLReq *req = (xGLXWaitGLReq *)pc;
+    GLXContextTag tag = req->contextTag;
+    __GLXcontext *glxc = NULL;
     int error;
+
+    if (tag) {
+	glxc = __glXLookupContextByTag(cl, tag);
+	if (!glxc)
+	    return __glXError(GLXBadContextTag);
     
-    if (!__glXForceCurrent(cl, req->contextTag, &error)) {
-	return error;
+	if (!__glXForceCurrent(cl, req->contextTag, &error))
+	    return error;
+
+	CALL_Finish( GET_DISPATCH(), () );
     }
-    CALL_Finish( GET_DISPATCH(), () );
+
+    if (glxc && glxc->drawPriv->waitGL)
+	(*glxc->drawPriv->waitGL)(glxc->drawPriv);
+
     return Success;
 }
 
 int __glXDisp_WaitX(__GLXclientState *cl, GLbyte *pc)
 {
     xGLXWaitXReq *req = (xGLXWaitXReq *)pc;
+    GLXContextTag tag = req->contextTag;
+    __GLXcontext *glxc = NULL;
     int error;
+
+    if (tag) {
+	glxc = __glXLookupContextByTag(cl, tag);
+	if (!glxc)
+	    return __glXError(GLXBadContextTag);
     
-    if (!__glXForceCurrent(cl, req->contextTag, &error)) {
-	return error;
+	if (!__glXForceCurrent(cl, req->contextTag, &error))
+	    return error;
     }
-    /*
-    ** In a multithreaded server that had separate X and GL threads, we would
-    ** have to wait for the X thread to finish before returning.  As it stands,
-    ** this sample implementation only supports singlethreaded servers, and
-    ** nothing needs to be done here.
-    */
+
+    if (glxc && glxc->drawPriv->waitGL)
+	(*glxc->drawPriv->waitGL)(glxc->drawPriv);
+
     return Success;
 }
 
diff --git a/glx/glxdrawable.h b/glx/glxdrawable.h
index 4f61f8b97..f5a040359 100644
--- a/glx/glxdrawable.h
+++ b/glx/glxdrawable.h
@@ -49,6 +49,8 @@ struct __GLXdrawable {
     GLboolean (*swapBuffers)(__GLXdrawable *);
     void      (*copySubBuffer)(__GLXdrawable *drawable,
 			       int x, int y, int w, int h);
+    void      (*waitX)(__GLXdrawable *);
+    void      (*waitGL)(__GLXdrawable *);
 
     DrawablePtr pDraw;
     XID drawId;
diff --git a/glx/glxdri.c b/glx/glxdri.c
index 8d614d08a..64606ab5a 100644
--- a/glx/glxdri.c
+++ b/glx/glxdri.c
@@ -706,6 +706,8 @@ __glXDRIscreenCreateDrawable(__GLXscreen *screen,
     private->base.destroy       = __glXDRIdrawableDestroy;
     private->base.swapBuffers   = __glXDRIdrawableSwapBuffers;
     private->base.copySubBuffer = __glXDRIdrawableCopySubBuffer;
+    private->base.waitX		= NULL;
+    private->base.waitGL	= NULL;
 
     __glXenterServer(GL_FALSE);
     retval = DRICreateDrawable(screen->pScreen, serverClient,
diff --git a/glx/glxdri2.c b/glx/glxdri2.c
index 836fea4d8..146ea828f 100644
--- a/glx/glxdri2.c
+++ b/glx/glxdri2.c
@@ -143,6 +143,39 @@ __glXDRIdrawableSwapBuffers(__GLXdrawable *drawable)
     return TRUE;
 }
 
+static void
+__glXDRIdrawableWaitX(__GLXdrawable *drawable)
+{
+    __GLXDRIdrawable *private = (__GLXDRIdrawable *) drawable;
+    BoxRec box;
+    RegionRec region;
+
+    box.x1 = 0;
+    box.y1 = 0;
+    box.x2 = private->width;
+    box.y2 = private->height;
+    REGION_INIT(drawable->pDraw->pScreen, &region, &box, 0);
+
+    DRI2CopyRegion(drawable->pDraw, &region,
+		   DRI2BufferFakeFrontLeft, DRI2BufferFrontLeft);
+}
+
+static void
+__glXDRIdrawableWaitGL(__GLXdrawable *drawable)
+{
+    __GLXDRIdrawable *private = (__GLXDRIdrawable *) drawable;
+    BoxRec box;
+    RegionRec region;
+
+    box.x1 = 0;
+    box.y1 = 0;
+    box.x2 = private->width;
+    box.y2 = private->height;
+    REGION_INIT(drawable->pDraw->pScreen, &region, &box, 0);
+
+    DRI2CopyRegion(drawable->pDraw, &region,
+		   DRI2BufferFrontLeft, DRI2BufferFakeFrontLeft);
+}
 
 static int
 __glXDRIdrawableSwapInterval(__GLXdrawable *drawable, int interval)
@@ -351,6 +384,8 @@ __glXDRIscreenCreateDrawable(__GLXscreen *screen,
     private->base.destroy       = __glXDRIdrawableDestroy;
     private->base.swapBuffers   = __glXDRIdrawableSwapBuffers;
     private->base.copySubBuffer = __glXDRIdrawableCopySubBuffer;
+    private->base.waitGL	= __glXDRIdrawableWaitGL;
+    private->base.waitX		= __glXDRIdrawableWaitX;
 
     if (DRI2CreateDrawable(pDraw)) {
 	    xfree(private);