Systemd/src/hibernate-resume/hibernate-resume-generator.c

107 lines
3.0 KiB
C

/***
This file is part of systemd.
Copyright 2014 Ivan Shapovalov
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 <stdio.h>
#include "alloc-util.h"
#include "fstab-util.h"
#include "log.h"
#include "mkdir.h"
#include "proc-cmdline.h"
#include "special.h"
#include "string-util.h"
#include "unit-name.h"
#include "util.h"
static const char *arg_dest = "/tmp";
static char *arg_resume_device = NULL;
static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
if (streq(key, "resume")) {
char *s;
if (proc_cmdline_value_missing(key, value))
return 0;
s = fstab_node_to_udev_node(value);
if (!s)
return log_oom();
free(arg_resume_device);
arg_resume_device = s;
}
return 0;
}
static int process_resume(void) {
_cleanup_free_ char *name = NULL, *lnk = NULL;
int r;
if (!arg_resume_device)
return 0;
r = unit_name_from_path_instance("systemd-hibernate-resume", arg_resume_device, ".service", &name);
if (r < 0)
return log_error_errno(r, "Failed to generate unit name: %m");
lnk = strjoin(arg_dest, "/" SPECIAL_SYSINIT_TARGET ".wants/", name);
if (!lnk)
return log_oom();
mkdir_parents_label(lnk, 0755);
if (symlink(SYSTEM_DATA_UNIT_PATH "/systemd-hibernate-resume@.service", lnk) < 0)
return log_error_errno(errno, "Failed to create symlink %s: %m", lnk);
return 0;
}
int main(int argc, char *argv[]) {
int r = 0;
if (argc > 1 && argc != 4) {
log_error("This program takes three or no arguments.");
return EXIT_FAILURE;
}
if (argc > 1)
arg_dest = argv[1];
log_set_target(LOG_TARGET_SAFE);
log_parse_environment();
log_open();
umask(0022);
/* Don't even consider resuming outside of initramfs. */
if (!in_initrd())
return EXIT_SUCCESS;
r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
if (r < 0)
log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
r = process_resume();
free(arg_resume_device);
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}