/*
     This file is part of GNUnet
     (C) 2010 Christian Grothoff (and other contributing authors)

     GNUnet is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published
     by the Free Software Foundation; either version 3, or (at your
     option) any later version.

     GNUnet is distributed in the hope that it will be useful, but
     WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     General Public License for more details.

     You should have received a copy of the GNU General Public License
     along with GNUnet; see the file COPYING.  If not, write to the
     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.
*/

/**
 * @file contrib/timeout_watchdog.c
 * @brief small tool starting a child process, waiting that it terminates or killing it after a given timeout period
 * @author Matthias Wachs
 */

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

static pid_t child;

static void sigchld_handler(int val)
{
  int status = 0;
  int ret = 0;
  
  waitpid (child, &status, 0);
  if (WIFEXITED(status) == 1)
  {
    ret = WEXITSTATUS(status);
    printf("Test process exited with result %u\n", ret);
  }
  if (WIFSIGNALED(status) == 1)
  {
    printf("Test process was signaled %u\n", WTERMSIG(status));
    ret = WTERMSIG(status);
  }   
  exit(ret);  
}

static void sigint_handler(int val)
{ 
  kill(0, val);
  exit(val);
}

int main(int argc, char *argv[])
{
int timeout = 0;
pid_t gpid =0;

if (argc < 3)
{  
  printf("arg 1: timeout in sec., arg 2: executable, arg<n> arguments\n");     
  exit(1);
}

timeout = atoi(argv[1]);

if (timeout == 0)
  timeout = 600;   

/* with getpgid() it does not compile, but getpgrp is the BSD version and working */
gpid = getpgrp();

signal(SIGCHLD, sigchld_handler);
signal(SIGABRT, sigint_handler);
signal(SIGFPE,  sigint_handler);
signal(SIGILL,  sigint_handler);
signal(SIGINT,  sigint_handler);
signal(SIGSEGV, sigint_handler);
signal(SIGTERM, sigint_handler);

child = fork();
if (child==0)
{
  /*  int setpgrp(pid_t pid, pid_t pgid); is not working on this machine*/
   //setpgrp (0, pid_t gpid);
   setpgid(0,gpid);
   execvp(argv[2],&argv[2]);
   exit(1);
}
if (child > 0)
{
  sleep(timeout);
  printf("Child processes were killed after timeout of %u seconds\n",timeout);
  kill(0,SIGTERM);
  exit(1);
}  
exit(1);
}

/* end of timeout_watchdog.c */