meillo@0: /* child.c, Copyright (C) 2000 by Oliver Kurth,
meillo@0:  *
meillo@0:  * This program is free software; you can redistribute it and/or modify
meillo@0:  * it under the terms of the GNU General Public License as published by
meillo@0:  * the Free Software Foundation; either version 2 of the License, or
meillo@0:  * (at your option) any later version.
meillo@0:  * 
meillo@0:  * This program is distributed in the hope that it will be useful,
meillo@0:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
meillo@0:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
meillo@0:  * GNU General Public License for more details.
meillo@0:  *
meillo@0:  * You should have received a copy of the GNU General Public License
meillo@0:  * along with this program; if not, write to the Free Software
meillo@0:  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
meillo@0:  */
meillo@0: 
meillo@0: #include <errno.h>
meillo@0: #include <stdio.h>
meillo@0: #include <stdlib.h>
meillo@0: #include <unistd.h>
meillo@0: #include <signal.h>
meillo@0: #include <sys/types.h>
meillo@0: #include <sys/socket.h>
meillo@0: #include <syslog.h>
meillo@0: #include <string.h>
meillo@0: 
meillo@0: #include "masqmail.h"
meillo@0: 
meillo@0: int volatile sigchild_seen = 0;
meillo@0: 
meillo@0: static
meillo@0: void sigchild_handler(int sig)
meillo@0: {
meillo@0:   sigchild_seen = 1;
meillo@0:   signal(SIGHUP, sigchild_handler);
meillo@0: }
meillo@0: 
meillo@0: int child(const char *command)
meillo@0: {
meillo@0:   int pipe[2];
meillo@0: 
meillo@0:   if (socketpair(AF_UNIX, SOCK_STREAM, 0, pipe) == 0){
meillo@0:     pid_t pid;
meillo@0:       
meillo@0:     /*
meillo@0:     sigchild_seen = 0;
meillo@0:     signal(SIGCHLD, sigchild_handler);
meillo@0:     */
meillo@0: 
meillo@0:     pid = fork();
meillo@0:     if(pid == 0){
meillo@0:       int i, max_fd = sysconf(_SC_OPEN_MAX);
meillo@0:       /* child */
meillo@0:       dup2(pipe[0], 0);
meillo@0:       dup2(pipe[0], 1);
meillo@0:       dup2(pipe[0], 2);
meillo@0: 
meillo@0:       if(max_fd <= 0) max_fd = 64;
meillo@0:       for(i = 3; i < max_fd; i++)
meillo@0: 	close(i);
meillo@0: 
meillo@0:       {
meillo@0: 	char *argv [] = { "/bin/sh", "-c", (char*) command, NULL };
meillo@0: 	execve (*argv, argv, NULL);
meillo@0:       }
meillo@0:       logwrite(LOG_ALERT, "execve failed: %s\n", strerror(errno));
meillo@0:       _exit(EXIT_FAILURE);
meillo@0:     }else if(pid == -1){
meillo@0:       return -1;
meillo@0:     }else{
meillo@0:       close(pipe[0]);
meillo@0:       return pipe[1];
meillo@0:     }
meillo@0:   }
meillo@0:   return -2;
meillo@0: }
meillo@0: 
meillo@0: