#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <syslog.h>

#include "utils.h"

#define _POSIX_PATH_MAX 256


void set_procname(char *arg0, const char *newname)
{
	memset(arg0, 0, _POSIX_PATH_MAX);
	strncpy(arg0, newname, _POSIX_PATH_MAX);
}

pid_t daemonize(int stay_foreground)
{
    int status = -1;
    pid_t pid;

    /* Fork off the parent process */
    pid = fork();

    /* An error occurred */
    if (pid < 0)
        return pid;

    /* Success: Let the parent terminate */
    if (pid > 0) {
        if (!stay_foreground)
            exit(EXIT_SUCCESS);
        waitpid(-1, &status, 0);
        exit(EXIT_SUCCESS);
    }

    /* On success: The child process becomes session leader */
    if (!stay_foreground && setsid() < 0)
        exit(EXIT_FAILURE);

    /* Catch, ignore and handle signals */
    //TODO: Implement a working signal handler */
    //signal(SIGCHLD, SIG_IGN);
    //signal(SIGHUP, SIG_IGN);

    if (!stay_foreground) {
        /* Fork off for the second time*/
        pid = fork();

        /* An error occurred */
        if (pid < 0)
            exit(EXIT_FAILURE);

        /* Success: Let the parent terminate */
        if (pid > 0) {
            exit(EXIT_SUCCESS);
        }
    }

    /* Set new file permissions */
    umask(0);

    if (stay_foreground)
        return pid;

    /* Change the working directory to the root directory */
    /* or another appropriated directory */
    chdir("/");

    /* Close all open file descriptors */
    int x;
    for (x = sysconf(_SC_OPEN_MAX); x>=0; x--)
    {
        close (x);
    }

    return pid;
}