/* child.c, Copyright (C) 2000 by Oliver Kurth,
 *
 * This program 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 2 of the License, or
 * (at your option) any later version.
 * 
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <syslog.h>
#include <string.h>

#include "masqmail.h"

int volatile sigchild_seen = 0;

static
void sigchild_handler(int sig)
{
  sigchild_seen = 1;
  signal(SIGHUP, sigchild_handler);
}

int child(const char *command)
{
  int pipe[2];

  if (socketpair(AF_UNIX, SOCK_STREAM, 0, pipe) == 0){
    pid_t pid;
      
    /*
    sigchild_seen = 0;
    signal(SIGCHLD, sigchild_handler);
    */

    pid = fork();
    if(pid == 0){
      int i, max_fd = sysconf(_SC_OPEN_MAX);
      /* child */
      dup2(pipe[0], 0);
      dup2(pipe[0], 1);
      dup2(pipe[0], 2);

      if(max_fd <= 0) max_fd = 64;
      for(i = 3; i < max_fd; i++)
	close(i);

      {
	char *argv [] = { "/bin/sh", "-c", (char*) command, NULL };
	execve (*argv, argv, NULL);
      }
      logwrite(LOG_ALERT, "execve failed: %s\n", strerror(errno));
      _exit(EXIT_FAILURE);
    }else if(pid == -1){
      return -1;
    }else{
      close(pipe[0]);
      return pipe[1];
    }
  }
  return -2;
}