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#include "daemon.h"
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/types.h>
#include <grp.h>
#include <pwd.h>
#include <string.h>
static gid_t get_gid(const char *grp)
{
char *eptr;
gid_t xid = strtoul(grp, &eptr, 10);
struct group *gr;
errno = 0;
if(!*eptr)
gr = getgrgid(xid);
else
gr = getgrnam(grp);
return !gr ? 0 : gr->gr_gid;
}
static uid_t get_uid(const char *usr, gid_t *gid)
{
char *eptr;
uid_t xid = strtoul(usr, &eptr, 10);
struct passwd *pw;
errno = 0;
if(!*eptr)
pw = getpwuid(xid);
else
pw = getpwnam(usr);
if(!pw)
return 0;
if(!gid)
*gid = pw->pw_gid;
return pw->pw_uid;
}
Daemon::Daemon()
{}
Daemon::~Daemon()
{}
int Daemon::run(const char *user, const char* group, bool detach)
{
int f;
int fd;
gid_t gid = 0;
uid_t uid = 0;
if(user && *user) {
uid = get_uid(user, &gid);
if(errno) {
fprintf(stderr, "Could resolve user \"%s\"", user);
perror("");
}
}
if(group && *group) {
gid = get_gid(group);
if(errno) {
fprintf(stderr, "Could not resolve group \"%s\"", group);
perror("");
}
}
chdir("/");
umask(0);
if(detach) {
switch(fork()) {
case -1:
perror("Fork in daemon.cc");
return 1;
case 0:
break;
default:
return 0;
}
}
if(gid) {
if(setgid(gid) != 0) {
fprintf(stderr, "Failed to change to group \"%s\" (gid: %d), quitting.\n", group, gid);
perror("");
fprintf(stderr, "Runnning daemon as current group\n");
}
}
if(uid) {
if(setuid(uid) != 0) {
fprintf(stderr, "Failed to change to user \"%s\" (uid: %d), quitting.\n", user, uid);
perror("");
fprintf(stderr, "Runnning daemon as current user\n");
}
}
fd = open("/dev/null", O_NOCTTY | O_RDWR, 0666);
dup2(0, fd);
dup2(1, fd);
dup2(2, fd);
close(fd);
setsid();
signal (SIGTERM, SIG_IGN);
signal (SIGHUP, SIG_IGN);
if(detach) signal (SIGINT, SIG_IGN);
return daemon_main();
}
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