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/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2011 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <string.h>
#include <unistd.h>
#include <libudev.h>
#include "util.h"
#include "mkdir.h"
int main(int argc, char *argv[]) {
struct udev *udev = NULL;
struct udev_enumerate *enumerator = NULL;
struct udev_list_entry *first, *item;
int i;
const char *seat = NULL;
char **new_argv;
char *path = NULL, *device_node = NULL;
int r;
FILE *f = NULL;
/* This binary will go away as soon as X natively supports
* display enumeration with udev in a way that covers both PCI
* and USB. */
/* This will simply determine the fb device id of the graphics
* device assigned to a seat and write a configuration file
* from it and then spawn the real X server. */
/* If this file is removed, don't forget to remove the code
* that invokes this in gdm and other display managers. */
for (i = 1; i < argc; i++)
if (streq(argv[i], "-seat"))
seat = argv[i+1];
if (isempty(seat) || streq(seat, "seat0")) {
argv[0] = (char*) X_SERVER;
execv(X_SERVER, argv);
log_error("Failed to execute real X server: %m");
goto fail;
}
udev = udev_new();
if (!udev) {
log_error("Failed to allocate udev environment.");
goto fail;
}
enumerator = udev_enumerate_new(udev);
if (!enumerator) {
log_error("Failed to allocate udev enumerator.");
goto fail;
}
udev_enumerate_add_match_subsystem(enumerator, "graphics");
udev_enumerate_add_match_tag(enumerator, seat);
r = udev_enumerate_scan_devices(enumerator);
if (r < 0) {
log_error("Failed to enumerate devices.");
goto fail;
}
first = udev_enumerate_get_list_entry(enumerator);
udev_list_entry_foreach(item, first) {
struct udev_device *d;
const char *dn;
d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));
if (!d)
continue;
dn = udev_device_get_devnode(d);
if (dn) {
device_node = strdup(dn);
if (!device_node) {
udev_device_unref(d);
log_error("Out of memory.");
goto fail;
}
}
udev_device_unref(d);
if (device_node)
break;
}
if (!device_node) {
log_error("Failed to find device node for seat %s.", seat);
goto fail;
}
r = mkdir_safe_label("/run/systemd/multi-session-x", 0755, 0, 0);
if (r < 0) {
log_error("Failed to create directory: %s", strerror(-r));
goto fail;
}
path = strappend("/run/systemd/multi-session-x/", seat);
if (!path) {
log_error("Out of memory.");
goto fail;
}
f = fopen(path, "we");
if (!f) {
log_error("Failed to write configuration file: %m");
goto fail;
}
fprintf(f,
"Section \"Device\"\n"
" Identifier \"udev\"\n"
" Driver \"fbdev\"\n"
" Option \"fbdev\" \"%s\"\n"
"EndSection\n"
"Section \"ServerFlags\"\n"
" Option \"AutoAddDevices\" \"True\"\n"
" Option \"AllowEmptyInput\" \"True\"\n"
" Option \"DontVTSwitch\" \"True\"\n"
"EndSection\n"
"Section \"InputClass\"\n"
" Identifier \"Force Input Devices to Seat\"\n"
" Option \"GrabDevice\" \"True\"\n"
"EndSection\n",
device_node);
fflush(f);
if (ferror(f)) {
log_error("Failed to write configuration file: %m");
goto fail;
}
fclose(f);
f = NULL;
new_argv = alloca(sizeof(char*) * (argc + 3 + 1));
memcpy(new_argv, argv, sizeof(char*) * (argc + 2 + 1));
new_argv[0] = (char*) X_SERVER;
new_argv[argc+0] = (char*) "-config";
new_argv[argc+1] = path;
new_argv[argc+2] = (char*) "-sharevts";
new_argv[argc+3] = NULL;
udev_enumerate_unref(enumerator);
enumerator = NULL;
udev_unref(udev);
udev = NULL;
free(device_node);
device_node = NULL;
execv(X_SERVER, new_argv);
log_error("Failed to execute real X server: %m");
fail:
if (enumerator)
udev_enumerate_unref(enumerator);
if (udev)
udev_unref(udev);
free(path);
free(device_node);
if (f)
fclose(f);
return EXIT_FAILURE;
}
|
