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/* See LICENSE file for copyright and license details. */
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/signalfd.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include "util.h"
static void sigpoweroff(void);
static void sigreap(void);
static void sigreboot(void);
static void spawn(char *const []);
static struct {
int sig;
void (*handler)(void);
} sigmap[] = {
{ SIGUSR1, sigpoweroff },
{ SIGCHLD, sigreap },
{ SIGINT, sigreboot },
};
#include "config.h"
static sigset_t set;
int
main(void)
{
struct signalfd_siginfo si;
int fd;
int i;
ssize_t n;
if (getpid() != 1)
return EXIT_FAILURE;
setsid();
sigemptyset(&set);
for (i = 0; i < LEN(sigmap); i++)
sigaddset(&set, sigmap[i].sig);
sigprocmask(SIG_BLOCK, &set, NULL);
fd = signalfd(-1, &set, SFD_CLOEXEC);
if (fd < 0)
eprintf("sinit: signalfd:");
spawn(rcinitcmd);
while (1) {
n = read(fd, &si, sizeof(si));
if (n < 0)
eprintf("sinit: read:");
if (n != sizeof(si))
continue;
for (i = 0; i < LEN(sigmap); i++)
if (sigmap[i].sig == si.ssi_signo)
sigmap[i].handler();
}
/* not reachable */
return EXIT_SUCCESS;
}
static void
sigpoweroff(void)
{
spawn(rcpoweroffcmd);
}
static void
sigreap(void)
{
while (waitpid(-1, NULL, WNOHANG) > 0)
;
}
static void
sigreboot(void)
{
spawn(rcrebootcmd);
}
static void
spawn(char *const argv[])
{
pid_t pid;
pid = fork();
if (pid < 0) {
weprintf("sinit: fork:");
} else if (pid == 0) {
sigprocmask(SIG_UNBLOCK, &set, NULL);
setsid();
setpgid(0, 0);
execvp(argv[0], argv);
weprintf("sinit: execvp %s:", argv[0]);
_exit(errno == ENOENT ? 127 : 126);
}
}
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