/*
* Copyright (c) 2008 Nicholas Marriott <[email protected]>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
* IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/

#include <sys/types.h>
#include <sys/ioctl.h>

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

#include "compat.h"

void fatal(const char *, ...);
void fatalx(const char *, ...);

pid_t
forkpty(int *master, char *name, struct termios *tio, struct winsize *ws)
{
       int     slave = -1;
       char   *path;
       pid_t   pid;

       if ((*master = open("/dev/ptmx", O_RDWR|O_NOCTTY)) == -1)
               return (-1);
       if (grantpt(*master) != 0)
               goto out;
       if (unlockpt(*master) != 0)
               goto out;

       if ((path = ptsname(*master)) == NULL)
               goto out;
       if (name != NULL)
               strlcpy(name, path, TTY_NAME_MAX);
       if ((slave = open(path, O_RDWR|O_NOCTTY)) == -1)
               goto out;

       switch (pid = fork()) {
       case -1:
               goto out;
       case 0:
               close(*master);

               setsid();
               if (ioctl(slave, TIOCSCTTY, NULL) == -1)
                       fatal("ioctl failed");

               if (tio != NULL && tcsetattr(slave, TCSAFLUSH, tio) == -1)
                       fatal("tcsetattr failed");
               if (ioctl(slave, TIOCSWINSZ, ws) == -1)
                       fatal("ioctl failed");

               dup2(slave, 0);
               dup2(slave, 1);
               dup2(slave, 2);
               if (slave > 2)
                       close(slave);
               return (0);
       }

       close(slave);
       return (pid);

out:
       if (*master != -1)
               close(*master);
       if (slave != -1)
               close(slave);
       return (-1);
}