From 6f8e6f9a19559c24947b6b22c68b4722865746ff Mon Sep 17 00:00:00 2001
From: Geoffrey McRae <geoff@hostfission.com>
Date: Thu, 5 Jan 2023 17:31:20 +1100
Subject: [PATCH] [client] x11: catch and print details of X11 errors with a
 backtrace

---
 client/displayservers/X11/x11.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/client/displayservers/X11/x11.c b/client/displayservers/X11/x11.c
index f36db977..a23c1be9 100644
--- a/client/displayservers/X11/x11.c
+++ b/client/displayservers/X11/x11.c
@@ -242,12 +242,31 @@ out:
   return;
 }
 
+static int x11ErrorHandler(Display * display, XErrorEvent * error)
+{
+  char errorText[1024];
+  XGetErrorText(display, error->error_code, errorText, sizeof(errorText));
+
+  DEBUG_ERROR("X11 Error: %s", errorText);
+  DEBUG_PRINT_BACKTRACE();
+  return 0;
+}
+
+static int x11IOErrorHandler(Display * display)
+{
+  DEBUG_FATAL("Fatal X11 IO Error");
+  return 0;
+}
+
 static bool x11Init(const LG_DSInitParams params)
 {
   XIDeviceInfo *devinfo;
   int count;
   int event, error;
 
+  XSetErrorHandler(x11ErrorHandler);
+  XSetIOErrorHandler(x11IOErrorHandler);
+
   memset(&x11, 0, sizeof(x11));
   x11.xValuator = -1;
   x11.yValuator = -1;