[xserver patch v4 3/5] glx: Enforce a 1:1 correspondence between GLX and X11 windows.

[Francisco Jerez]

The spec says (regarding glXCreateWindow): "If there is already a
GLXFBConfig associated with win (as a result of a previous
glXCreateWindow call), then a BadAlloc error is generated.". It will
also come useful to implement DRI2InvalidateBuffers for the indirect
case.

Signed-off-by: Francisco Jerez <currojerez at riseup.net>
---
 glx/glxcmds.c   |   51 +++++++++++++++++++++++++++++++++++++++++++++------
 glx/glxserver.h |    1 +
 2 files changed, 46 insertions(+), 6 deletions(-)

diff --git a/glx/glxcmds.c b/glx/glxcmds.c
index 77afbf4..0e1c89c 100644
--- a/glx/glxcmds.c
+++ b/glx/glxcmds.c
@@ -51,6 +51,15 @@
 #include "indirect_table.h"
 #include "indirect_util.h"
 
+static int glxWindowPrivateKeyIndex;
+static DevPrivateKey glxWindowPrivateKey = &glxWindowPrivateKeyIndex;
+
+__GLXdrawable *
+glxGetDrawableFromWindow(WindowPtr pWin)
+{
+	return dixLookupPrivate(&pWin->devPrivates, glxWindowPrivateKey);
+}
+
 static int
 validGlxScreen(ClientPtr client, int screen, __GLXscreen **pGlxScreen, int *err)
 {
@@ -473,6 +482,7 @@ __glXGetDrawable(__GLXcontext *glxc, GLXDrawable drawId, ClientPtr client,
 		 int *error)
 {
     DrawablePtr pDraw;
+    WindowPtr pWin;
     __GLXdrawable *pGlxDraw;
     int rc;
 
@@ -499,6 +509,12 @@ __glXGetDrawable(__GLXcontext *glxc, GLXDrawable drawId, ClientPtr client,
 	return NULL;
     }
 
+    pWin = (WindowPtr)pDraw;
+
+    pGlxDraw = glxGetDrawableFromWindow(pWin);
+    if (pGlxDraw)
+	    return pGlxDraw;
+
     if (pDraw->pScreen != glxc->pGlxScreen->pScreen) {
 	client->errorValue = pDraw->pScreen->myNum;
 	*error = BadMatch;
@@ -519,6 +535,8 @@ __glXGetDrawable(__GLXcontext *glxc, GLXDrawable drawId, ClientPtr client,
 	return NULL;
     }
 
+    dixSetPrivate(&pWin->devPrivates, glxWindowPrivateKey, pGlxDraw);
+
     return pGlxDraw;
 }
 
@@ -1107,9 +1125,10 @@ __glXDrawableRelease(__GLXdrawable *drawable)
     }
 }
 
-static int 
+static int
 DoCreateGLXDrawable(ClientPtr client, __GLXscreen *pGlxScreen, __GLXconfig *config,
-		    DrawablePtr pDraw, XID glxDrawableId, int type)
+		    DrawablePtr pDraw, XID glxDrawableId, int type,
+		    __GLXdrawable **ret)
 {
     __GLXdrawable *pGlxDraw;
 
@@ -1128,6 +1147,9 @@ DoCreateGLXDrawable(ClientPtr client, __GLXscreen *pGlxScreen, __GLXconfig *conf
 	return BadAlloc;
     }
 
+    if (ret)
+	*ret = pGlxDraw;
+
     return Success;
 }
 
@@ -1149,7 +1171,7 @@ DoCreateGLXPixmap(ClientPtr client, __GLXscreen *pGlxScreen, __GLXconfig *config
     }
 
     err = DoCreateGLXDrawable(client, pGlxScreen, config, pDraw,
-			      glxDrawableId, GLX_DRAWABLE_PIXMAP);
+			      glxDrawableId, GLX_DRAWABLE_PIXMAP, NULL);
 
     if (err == Success)
 	((PixmapPtr) pDraw)->refcnt++;
@@ -1305,7 +1327,7 @@ DoCreatePbuffer(ClientPtr client, int screenNum, XID fbconfigId,
     __glXleaveServer(GL_FALSE);
 
     return DoCreateGLXDrawable(client, pGlxScreen, config, &pPixmap->drawable,
-			       glxDrawableId, GLX_DRAWABLE_PBUFFER);
+			       glxDrawableId, GLX_DRAWABLE_PBUFFER, NULL);
 }
 
 int __glXDisp_CreatePbuffer(__GLXclientState *cl, GLbyte *pc)
@@ -1409,6 +1431,8 @@ int __glXDisp_CreateWindow(__GLXclientState *cl, GLbyte *pc)
     __GLXscreen		*pGlxScreen;
     ClientPtr		 client = cl->client;
     DrawablePtr		 pDraw;
+    WindowPtr		 pWin;
+    __GLXdrawable	*pGlxDraw;
     int			 err;
 
     if (!validGlxScreen(client, req->screen, &pGlxScreen, &err))
@@ -1422,11 +1446,26 @@ int __glXDisp_CreateWindow(__GLXclientState *cl, GLbyte *pc)
 	return BadWindow;
     }
 
+    pWin = (WindowPtr)pDraw;
+
+    /* Make sure there're no already associated GLX drawables. */
+    if (glxGetDrawableFromWindow(pWin)) {
+	client->errorValue = req->window;
+	return BadAlloc;
+    }
+
     if (!validGlxFBConfigForWindow(client, config, pDraw, &err))
 	return err;
 
-    return DoCreateGLXDrawable(client, pGlxScreen, config,
-			       pDraw, req->glxwindow, GLX_DRAWABLE_WINDOW);
+    err = DoCreateGLXDrawable(client, pGlxScreen, config,
+			      pDraw, req->glxwindow,
+			      GLX_DRAWABLE_WINDOW, &pGlxDraw);
+    if (err)
+	return err;
+
+    dixSetPrivate(&pWin->devPrivates, glxWindowPrivateKey, pGlxDraw);
+
+    return Success;
 }
 
 int __glXDisp_DestroyWindow(__GLXclientState *cl, GLbyte *pc)
diff --git a/glx/glxserver.h b/glx/glxserver.h
index 1daf977..3c49b5e 100644
--- a/glx/glxserver.h
+++ b/glx/glxserver.h
@@ -80,6 +80,7 @@ typedef struct __GLXcontext __GLXcontext;
 
 extern __GLXscreen *glxGetScreen(ScreenPtr pScreen);
 extern __GLXclientState *glxGetClient(ClientPtr pClient);
+extern __GLXdrawable *glxGetDrawableFromWindow(WindowPtr pWin);
 
 /************************************************************************/
 
-- 
1.6.4.4