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/**
* Copyright © 2015, 2016 Mattias Andrée <maandree@member.fsf.org>
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#include "common.h"
#include "daemonise.h"
COMMAND("satd")
USAGE("[-f]")
/**
* Create and lock the lock file, and its directory.
*
* @return A file descriptor to the lock file, -1 on error.
*/
static int
create_lock(void)
{
const char *dir;
char *path;
char *p;
pid_t pid = getpid();
int fd = -1, saved_errno = 0;
/* Create directory. */
dir = getenv("XDG_RUNTIME_DIR"), dir = (dir ? dir : "/run");
t (!(path = malloc(strlen(dir) * sizeof(char) + sizeof("/" PACKAGE "/lock"))));
p = stpcpy(stpcpy(path, dir), "/" PACKAGE);
t (mkdir(path, S_IRWXU) && (errno != EEXIST));
/* Open file. */
stpcpy(p, "/lock");
t (fd = open(path, O_RDWR | O_CREAT /* but not O_EXCL or O_TRUNC */, S_IRUSR | S_IWUSR), fd == -1);
/* Check that the daemon is not running, and mark it as running. */
if (flock(fd, LOCK_EX | LOCK_NB)) {
t (errno != EWOULDBLOCK);
fprintf(stderr, "%s: the daemon is already in reading.\n", argv0);
errno = 0;
goto fail;
}
/* Store PID in the file. */
/* Yes it is coming similar to a PID file, but this works if the started with -f. */
t (pwrite(fd, &pid, sizeof(pid), (off_t)0) < (ssize_t)sizeof(pid));
goto done;
fail:
saved_errno = errno, close(fd), fd = -1;
done:
free(path), errno = saved_errno;
return fd;
}
/**
* The sat daemon initialisation.
*
* @param argc Any value in [0, 2] is accepted.
* @param argv The name of the process, and -f if the process
* shall not be daemonised.
* @return 0 The process was successful.
* @return 1 The process failed queuing the job.
* @return 2 User error, you do not know what you are doing.
*/
int
main(int argc, char *argv[])
{
int state = -1, boot = -1, real = -1, lock = -1, foreground = 0;
char *path = NULL;
struct itimerspec spec;
/* Parse command line. */
if (argc > 0) argv0 = argv[0];
if (argc > 2) usage();
if ((argc == 2) && (!(foreground = !strcmp(argv[1], "-f"))))
usage();
/* Get hook-script pathname. */
t (set_hookpath());
/* Open/create lock file and state file, and create socket. */
GET_FD(lock, LOCK_FILENO, create_lock());
GET_FD(state, STATE_FILENO, open_state(O_RDWR | O_CREAT, &path));
/* Create timers. */
GET_FD(boot, BOOT_FILENO, timerfd_create(CLOCK_BOOTTIME, 0));
GET_FD(real, REAL_FILENO, timerfd_create(CLOCK_REALTIME, 0));
/* Configure timers. */
memset(&spec, 0, sizeof(spec));
t (timerfd_settime(boot, TFD_TIMER_ABSTIME, &spec, NULL));
t (timerfd_settime(real, TFD_TIMER_ABSTIME, &spec, NULL));
/* Daemonise. */
t (foreground ? 0 : daemonise("satd", DAEMONISE_KEEP_FDS | DAEMONISE_NEW_PID, 3, 4, 5, 6, -1));
/* Change to a process image without all this initialisation text. */
execl(LIBEXECDIR "/" PACKAGE "/satd-diminished", argv0, path, NULL);
fail:
if (errno)
perror(argv0);
free(path);
close(state), close(boot), close(real), close(lock);
undaemonise();
return 1;
}
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