X-Git-Url: https://git.artsoft.org/?a=blobdiff_plain;f=src%2Flibgame%2Fx11.c;h=fe022c5bf3f8ddb1f50d9d8c7b776c4f7694894b;hb=9991027ba0e61f105a15d517461614fce184ba48;hp=12f4e1e4268cabf8e8b39591d442bc67905d3f99;hpb=1ca582ff344bd825e03229636cee6d006e19251f;p=rocksndiamonds.git

diff --git a/src/libgame/x11.c b/src/libgame/x11.c
index 12f4e1e4..fe022c5b 100644
--- a/src/libgame/x11.c
+++ b/src/libgame/x11.c
@@ -22,6 +22,13 @@
 static void X11InitDisplay();
 static DrawWindow *X11InitWindow();
 
+static int X11DebugErrorHandler(Display *display, XErrorEvent *event)
+{
+  int x = 0;
+
+  return 1 / x;		/* !!! crash program to give backtrace in gdb !!! */
+}
+
 void X11InitVideoDisplay(void)
 {
   /* initialize X11 video */
@@ -55,6 +62,14 @@ static void X11InitDisplay()
     Error(ERR_EXIT, "cannot connect to X server %s",
 	  XDisplayName(options.display_name));
 
+  if (options.debug_x11_sync)
+  {
+    Error(ERR_WARN, "running in X11 synchronous mode (debug only)");
+
+    XSynchronize(display, True);
+    XSetErrorHandler(X11DebugErrorHandler);
+  }
+
   screen = DefaultScreen(display);
   visual = DefaultVisual(display, screen);
   depth  = DefaultDepth(display, screen);