path: root/camel/camel-process.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
 *  Authors: Jeffrey Stedfast <fejj@ximian.com>
 *
 *  Copyright 2003 Ximian, Inc. (www.ximian.com)
 *
 *  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., 59 Temple Street #330, Boston, MA 02111-1307, USA.
 *
 */


#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <unistd.h>
#include <fcntl.h>
#include <errno.h>

#include "camel-process.h"


pid_t
camel_process_fork (const char *path, char **argv, int *infd, int *outfd, int *errfd, CamelException *ex)
{
    int errnosav, fd[6], i;
    pid_t pid;
    
    for (i = 0; i < 6; i++)
        fds[i] = -1;
    
    for (i = 0; i < 6; i += 2) {
        if (pipe (fd + i) == -1) {
            errnosav = errno;
            camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                          _("Failed to create pipe to '%s': %s"),
                          argv[0], strerror (errno));
            
            for (i = 0; i < 6; i++) {
                if (fd[i] == -1)
                    break;
                close (fd[i]);
            }
            
            errno = errnosav;
            
            return -1;
        }
    }
    
    if (!(pid = fork ())) {
        /* child process */
        int maxfd, nullfd = -1;
        
        if (!outfd || !errfd)
            nullfd = open ("/dev/null", O_WRONLY);
        
        if (dup2 (fd[0], STDIN_FILENO) == -1)
            _exit (255);
        
        if (dup2 (outfd ? fd[3] : nullfd, STDOUT_FILENO) == -1)
            _exit (255);
        
        if (dup2 (errfd ? fd[5] : nullfd, STDERR_FILENO) == -1)
            _exit (255);
        
        setsid ();
        
        if ((maxfd = sysconf (_SC_OPEN_MAX)) > 0) {
            for (i = 0; i < maxfd; i++) {
                if (i != STDIN_FILENO && i != STDOUT_FILENO && i != STDERR_FILENO)
                    close (i);
            }
        }
        
        execv (path, argv);
        _exit (255);
    } else if (pid == -1) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("Failed to create create child process '%s': %s"),
                      argv[0], strerror (errno));
        return -1;
    }
    
    /* parent process */
    close (fd[0]);
    close (fd[3]);
    close (fd[5]);
    
    if (infd)
        *infd = fd[1];
    else
        close (fd[1]);
    
    if (outfd)
        *outfd = fd[2];
    else
        close (fd[2]);
    
    if (errfd)
        *errfd = fd[4];
    else
        close (fd[4]);
    
    return pid;
}


int
camel_process_wait (pid_t pid)
{
    sigset_t mask, omask;
    int status;
    pid_t r;
    
    sigemptyset (&mask);
    sigaddset (&mask, SIGALRM);
    sigprocmask (SIG_BLOCK, &mask, &omask);
    alarm (1);
    
    r = waitpid (pid, &status, 0);
    
    alarm (0);
    sigprocmask (SIG_SETMASK, &omask, NULL);
    
    if (r == (pid_t) -1 && errno == EINTR) {
        kill (pid, SIGTERM);
        sleep (1);
        r = waitpid (pid, &status, WNOHANG);
        if (r == (pid_t) 0) {
            kill (pid, SIGKILL);
            sleep (1);
            r = waitpid (pid, &status, WNOHANG);
        }
    }
    
    if (r != (pid_t) -1 && WIFEXITED (status))
        return WEXITSTATUS (status);
    else
        return -1;
}