Don't try to send grants for not realized windows

gui-agent/Makefile

@@ -23,9 +23,9 @@ CC ?= gcc
 CFLAGS += -I../include/ `pkg-config --cflags vchan` -g -Wall -Wextra -Werror -fPIC \
 	  -Wmissing-prototypes -Wstrict-prototypes -Wold-style-declaration \
 	  -Wold-style-definition
-OBJS = vmside.o txrx-vchan.o error.o list.o encoding.o
+OBJS = vmside.o txrx-vchan.o error.o list.o encoding.o video-ext-client.o
 LIBS = -lX11 -lXdamage -lXcomposite -lXfixes `pkg-config --libs vchan` -lqubesdb \
-	   -lunistring
+	   -lunistring -lXext
 
 
 all: qubes-gui qubes-gui-runuser

gui-agent/video-ext-client.c

@@ -0,0 +1,117 @@
+/*
+ * The Qubes OS Project, https://www.qubes-os.org/
+ *
+ * Copyright (C) 2025  Simon Gaiser <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "video-ext-client.h"
+
+#include <X11/Xlibint.h>
+#include <X11/extensions/Xext.h>
+#include <X11/extensions/extutil.h>
+
+static int close_display(Display *dpy, XExtCodes *codes);
+static Bool wire_to_event(Display *dpy, XEvent *libEv, xEvent *wireEv);
+
+static XExtensionHooks ext_hooks = {
+    NULL,          // create_gc
+    NULL,          // copy_gc
+    NULL,          // flush_gc
+    NULL,          // free_gc
+    NULL,          // create_font
+    NULL,          // free_font
+    close_display, // close_display
+    wire_to_event, // wire_to_event
+    NULL,          // event_to_wire (we don't need SendEvent)
+    NULL,          // error
+    NULL,          // error_string
+};
+
+static XExtensionInfo _ext_info;
+static XExtensionInfo *ext_info = &_ext_info;
+static const char * ext_name = QVE_NAME;
+
+#define QVECheckExtension(dpy, info, val) \
+    XextCheckExtension(dpy, info, ext_name, val)
+
+static XEXT_GENERATE_FIND_DISPLAY(find_display,
+                                  ext_info,
+                                  ext_name,
+                                  &ext_hooks,
+                                  QVENumberEvents,
+                                  NULL);
+
+static XEXT_GENERATE_CLOSE_DISPLAY(close_display, ext_info);
+
+static Bool
+wire_to_event(Display *dpy, XEvent *libEv, xEvent *wireEv)
+{
+    XExtDisplayInfo *info = find_display(dpy);
+
+    QVECheckExtension(dpy, info, False);
+
+    BYTE type = wireEv->u.u.type;
+    if ((type & 0x7f) != info->codes->first_event + QVEWindowRealized) {
+        return False;
+    }
+
+    XQVEWindowRealizedEvent *qLibEv = (XQVEWindowRealizedEvent *)libEv;
+    xQVEWindowRealizedEvent *qWireEv = (xQVEWindowRealizedEvent *)wireEv;
+
+    qLibEv->type = type & 0x7f;
+    qLibEv->serial = _XSetLastRequestRead(dpy, (xGenericReply *)wireEv);
+    qLibEv->send_event = (type & 0x80) != 0;
+    qLibEv->display = dpy;
+    qLibEv->window = qWireEv->window;
+    qLibEv->unrealized =
+        (qWireEv->detail & QVEWindowRealizedDetailUnrealized) != 0;
+
+    return True;
+}
+
+Bool
+XQVEQueryExtension(Display *dpy, int *event_base)
+{
+    XExtDisplayInfo *info = find_display(dpy);
+
+    if (!XextHasExtension(info)) {
+        return False;
+    }
+
+    *event_base = info->codes->first_event;
+    return True;
+}
+
+Bool
+XQVERegister(Display *dpy)
+{
+    XExtDisplayInfo *info = find_display(dpy);
+
+    QVECheckExtension(dpy, info, False);
+
+    LockDisplay(dpy);
+    xQVEReq *req;
+#define X_QVE X_QVERegister
+    GetReq(QVE, req);
+#undef X_QVE
+    req->reqType = info->codes->major_opcode;
+    req->QVEReqType = X_QVERegister;
+    UnlockDisplay(dpy);
+    SyncHandle();
+
+    return True;
+}

gui-agent/video-ext-client.h

@@ -0,0 +1,36 @@
+/*
+ * The Qubes OS Project, https://www.qubes-os.org/
+ *
+ * Copyright (C) 2025  Simon Gaiser <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#pragma once
+
+#include "qubes-video-ext.h"
+#include <X11/Xlib.h>
+
+typedef struct {
+    int type;
+    unsigned long serial;
+    Bool send_event;
+    Display *display;
+    Window window;
+    Bool unrealized;
+} XQVEWindowRealizedEvent;
+
+Bool XQVERegister(Display *dpy);
+Bool XQVEQueryExtension(Display *dpy, int *event_base);