12to11/xerror.c
2022-09-12 13:24:50 +00:00

119 lines
3.2 KiB
C

/* Wayland compositor running on top of an X server.
Copyright (C) 2022 to various contributors.
This file is part of 12to11.
12to11 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 3 of the License, or (at your
option) any later version.
12to11 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 12to11. If not, see <https://www.gnu.org/licenses/>. */
#include <stdio.h>
#include <stdlib.h>
#include "compositor.h"
#include <X11/extensions/XInput.h>
/* X error handling routines. The entry point into this code is
CatchXErrors, which starts catching X errors in the following code,
and UncatchXErrors, which syncs (if necessary) and saves any
received XErrorEvent into a provided buffer.
This code is not reentrant since it doesn't have to take care of
many complicated scenarios that the Emacs code needs. */
/* First request from which errors should be caught. -1 if we are not
currently catching errors. */
static unsigned long first_error_req;
/* XErrorEvent any error that happens while errors are being caught
will be saved in. */
static XErrorEvent error;
/* True if any error was caught. */
static Bool error_caught;
void
CatchXErrors (void)
{
first_error_req = XNextRequest (compositor.display);
error_caught = False;
}
Bool
UncatchXErrors (XErrorEvent *event)
{
/* Try to avoid syncing to obtain errors if we know none could have
been generated, because either no request has been made, or all
requests have been processed. */
if ((LastKnownRequestProcessed (compositor.display)
!= XNextRequest (compositor.display) - 1)
&& (NextRequest (compositor.display)
> first_error_req))
/* If none of those conditions apply, catch errors now. */
XSync (compositor.display, False);
first_error_req = -1;
if (!event)
return error_caught;
if (!error_caught)
return False;
*event = error;
return True;
}
static int
ErrorHandler (Display *display, XErrorEvent *event)
{
char buf[256];
if (first_error_req != -1
&& event->serial >= first_error_req)
{
error = *event;
error_caught = True;
return 0;
}
if (XLHandleErrorForDmabuf (event))
return 0;
if (event->error_code == (xi_first_error + XI_BadDevice))
/* Various XI requests can result in XI_BadDevice errors if the
device has been removed on the X server, but we have not yet
processed the corresponding hierarchy events. */
return 0;
XGetErrorText (display, event->error_code, buf, sizeof buf);
fprintf (stderr, "X protocol error: %s on protocol request %d\n",
buf, event->request_code);
exit (70);
}
void
InitXErrors (void)
{
first_error_req = -1;
XSetErrorHandler (ErrorHandler);
/* Allow debugging by setting an environment variable. */
if (getenv ("SYNCHRONIZE"))
XSynchronize (compositor.display, True);
}