Install custom XIOError handler to abort on IO error

Allows debugging the core file to see what went wrong

Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/src/xlib_client.c b/src/xlib_client.c
index a612910..80bd66a 100644
--- a/src/xlib_client.c
+++ b/src/xlib_client.c
@@ -29,14 +29,29 @@
 #include <X11/Xlibint.h>
 #include <assert.h>
 #include <sys/types.h>
+#include <stdio.h>
+#include <errno.h>
 
 static pid_t server_pid;
 
+static int
+XhivIOError(Display *dpy) {
+    fprintf(stderr, "XIO:  fatal IO error %d (%s) on X server \"%s\"\r\n",
+            errno, strerror (errno), DisplayString (dpy));
+    fprintf (stderr,
+         "      after %lu requests (%lu known processed) with %d events remaining.\r\n",
+             NextRequest(dpy) - 1, LastKnownRequestProcessed(dpy),
+             QLength(dpy));
+    abort();
+}
+
 Display *
 XhivOpenDisplay(xhiv_response *responses) {
     char *dpyname;
     Display *dpy;
 
+    XSetIOErrorHandler(XhivIOError);
+
     dpyname = XhivOpenServer(responses, &server_pid);
     assert(dpyname != NULL);