1
0
mirror of https://github.com/systemd/systemd.git synced 2024-11-08 11:27:32 +03:00
systemd/src/system-update-generator/system-update-generator.c
2014-06-13 13:26:32 +02:00

78 lines
2.0 KiB
C

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2012 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 <errno.h>
#include <unistd.h>
#include "log.h"
#include "util.h"
#include "unit-name.h"
#include "path-util.h"
/*
* Implements the logic described in
* http://freedesktop.org/wiki/Software/systemd/SystemUpdates
*/
static const char *arg_dest = "/tmp";
static int generate_symlink(void) {
const char *p = NULL;
if (access("/system-update", F_OK) < 0) {
if (errno == ENOENT)
return 0;
log_error("Failed to check for system update: %m");
return -EINVAL;
}
p = strappenda(arg_dest, "/default.target");
if (symlink(SYSTEM_DATA_UNIT_PATH "/system-update.target", p) < 0) {
log_error("Failed to create symlink %s: %m", p);
return -errno;
}
return 0;
}
int main(int argc, char *argv[]) {
int r;
if (argc > 1 && argc != 4) {
log_error("This program takes three or no arguments.");
return EXIT_FAILURE;
}
if (argc > 1)
arg_dest = argv[2];
log_set_target(LOG_TARGET_SAFE);
log_parse_environment();
log_open();
umask(0022);
r = generate_symlink();
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}