int main(int argc, char *argv[]) {
pager = getenv("PAGER");
if (pager == NULL)
pager = "less";
/* Set number of processes and pipes depending on if we should run grep */
args = (argc > 1) ? 1 : 0;
num_procs = 3 + args;
num_pipes = 2 + args;
pipes_init();
exec_proc(STDIN_FILENO, pipes[0][1], "printenv", argv);
if (args) {
exec_proc(pipes[0][0], pipes[args][1], "grep", argv);
}
exec_proc(pipes[args][0], pipes[1 + args][1], "sort", argv);
exec_proc(pipes[1 +args][0], STDOUT_FILENO, "less", argv);
close_all_fd();
wait_for_kids();
return 0;
}
void wf_daemon_action(int nochdir, int noclose, __sighandler_t exit_call)
{
int i, fd;
pid_t pid;
struct rlimit rl;
struct sigaction sa;
// clear file creation mask
umask(0);
if(getrlimit(RLIMIT_NOFILE, &rl) < 0)
rl.rlim_max = 0;
pid = fork();
if(pid < 0)
exit(1);
else if(pid == 0)
exit(0);
else
setsid();
sa.sa_handler = SIG_IGN;
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
sigaction(SIGHUP, &sa, NULL);
if(fork()!= 0)
exit(0);
if(!nochdir)
chdir("/");
if(rl.rlim_max == 0)
close_all_fd(!noclose);
else{
if(rl.rlim_max == RLIM_INFINITY)
rl.rlim_max = 1024;
for(i = noclose ? 3 : 0; i<rl.rlim_max; i++)
close(i);
}
if(!noclose){
fd = open("/dev/null", O_WRONLY);
if(fd >= 0){
if(fd != STDOUT_FILENO)
dup2(fd, STDOUT_FILENO);
if(fd != STDERR_FILENO)
dup2(fd, STDERR_FILENO);
close(fd);
}
}
signal(SIGINT, exit_call);
signal(SIGTERM, exit_call);
}
static void __core_restart(int soft)
{
char exe[PATH_MAX];
pthread_sigmask(SIG_SETMASK, &orig_set, NULL);
#ifdef USE_BACKUP
if (soft)
backup_restore_fd();
else
#endif
close_all_fd();
sprintf(exe, "/proc/%u/exe", getpid());
readlink(exe, exe, PATH_MAX);
while (1) {
execv(exe, argv);
sleep(3);
}
}
/*
Forks and executes the "program" with arguments args in a different process.
STDIN and STDOUT are redirected to fd_in and fd_out and used for the required
inter-process communication.
*/
pid_t exec_proc(int fd_in, int fd_out, char *program, char *argv[]) {
pid_t pid = fork();
if (pid == 0) {
/*Duplicate stdin and stdout file descriptors*/
int ret;
char *ptr[2];
ret = dup2(fd_in, STDIN_FILENO);
if (ret == -1) {
perror("exec_proc\n");
exit(-1);
}
ret = dup2(fd_out, STDOUT_FILENO);
if (ret == -1) {
perror("exec_proc\n");
exit(-1);
}
/* Close all file descriptors in pipes */
close_all_fd();
/* NULL args for all programs but grep */
ptr[0] = program;
ptr[1] = (char*) NULL;
/* Execute */
if (!strcmp(program, "grep")) {
execvp(program, argv);
exit(-1);
} else if (!strcmp(program, pager)) {
int exec_ret;
exec_ret = execvp(program, ptr);
/* If pager fails, default to more */
if (exec_ret == -1) {
execvp("more", ptr);
}
} else {
execvp(program, ptr);
exit(-1);
}
} else if (pid == -1) {
perror("exec_proc");
exit(-1);
}
return pid;
}
