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//#include "daemon.h"
#include "umbrella.h"
#include "log.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <signal.h>
#include <sys/stat.h>
#include <sys/signalfd.h>
/*
* Create a directory and all parents, like mkdir -p.
* Returns 0 if the directory exists or was created, -1 on error.
*/
static int mkdirp(const char *path, mode_t mode) {
char tmp[MAX_PATH];
char *p;
size_t len;
snprintf(tmp, sizeof(tmp), "%s", path);
len = strlen(tmp);
if (tmp[len - 1] == '/')
tmp[len - 1] = '\0';
for (p = tmp + 1; *p; p++) {
if (*p == '/') {
*p = '\0';
if (mkdir(tmp, mode) != 0 && errno != EEXIST)
return -1;
*p = '/';
}
}
if (mkdir(tmp, mode) != 0 && errno != EEXIST)
return -1;
return 0;
}
int daemon_daemonize(int foreground) {
if (foreground)
return 0;
pid_t pid = fork();
if (pid < 0) {
perror("fork");
return -1;
}
if (pid > 0)
exit(0); /* parent exits */
/* Child: become session leader */
if (setsid() < 0) {
perror("setsid");
return -1;
}
/* Fork again so we're not a session leader (can't acquire a tty) */
pid = fork();
if (pid < 0) {
perror("fork");
return -1;
}
if (pid > 0)
exit(0);
/* Redirect stdin/stdout/stderr to /dev/null */
int dev_null = open("/dev/null", O_RDWR);
if (dev_null >= 0) {
dup2(dev_null, STDIN_FILENO);
dup2(dev_null, STDOUT_FILENO);
dup2(dev_null, STDERR_FILENO);
if (dev_null > STDERR_FILENO)
close(dev_null);
}
umask(027);
return 0;
}
int daemon_write_pid(void) {
/* Ensure the run directory exists */
if (mkdirp("/run/umbrella", 0755) != 0 && errno != EEXIST) {
log_error("Could not create /run/umbrella: %s", strerror(errno));
return -1;
}
FILE *f = fopen(UMBRELLA_PID_FILE, "w");
if (!f) {
log_error("Could not write pid file %s: %s",
UMBRELLA_PID_FILE, strerror(errno));
return -1;
}
fprintf(f, "%d\n", (int)getpid());
fclose(f);
return 0;
}
int daemon_init(void) {
/* Ensure runtime and log directories exist */
if (mkdirp("/run/umbrella", 0755) != 0 && errno != EEXIST) {
log_error("mkdirp /run/umbrella: %s", strerror(errno));
return -1;
}
if (mkdirp("/var/log/umbrella", 0755) != 0 && errno != EEXIST) {
log_error("mkdirp /var/log/umbrella: %s", strerror(errno));
return -1;
}
if (daemon_write_pid() != 0)
return -1;
/*
* Set up a signalfd so signals arrive as readable events on the
* epoll loop rather than interrupting syscalls unpredictably.
* We block the signals first, then read them via the fd.
*/
sigset_t mask;
sigemptyset(&mask);
sigaddset(&mask, SIGINT);
sigaddset(&mask, SIGTERM);
sigaddset(&mask, SIGCHLD); /* child process state changes */
sigaddset(&mask, SIGHUP); /* reload config */
sigaddset(&mask, SIGPIPE); /* ignore broken pipe */
if (sigprocmask(SIG_BLOCK, &mask, NULL) != 0) {
log_error("sigprocmask: %s", strerror(errno));
return -1;
}
int sfd = signalfd(-1, &mask, SFD_NONBLOCK | SFD_CLOEXEC);
if (sfd < 0) {
log_error("signalfd: %s", strerror(errno));
return -1;
}
g.signal_fd = sfd;
log_info("Daemon initialized (pid %d)", (int)getpid());
return 0;
}
void daemon_cleanup(void) {
log_info("Cleaning up...");
unlink(UMBRELLA_PID_FILE);
unlink(UMBRELLA_SOCK_PATH);
}
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