compat/forkpty-aix.c

   1 /*
   2  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
   3  *
   4  * Permission to use, copy, modify, and distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
  13  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  14  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include <sys/types.h>
  18 #include <sys/ioctl.h>
  19
  20 #include <fcntl.h>
  21 #include <stdlib.h>
  22 #include <stropts.h>
  23 #include <unistd.h>
  24 #include <errno.h>
  25
  26 #include "compat.h"
  27
  28 void fatal(const char *, ...);
  29 void fatalx(const char *, ...);
  30
  31 pid_t
  32 forkpty(int *master, __unused char *name, struct termios *tio,
  33     struct winsize *ws)
  34 {
  35         int     slave = -1, fd, pipe_fd[2];
  36         char   *path, dummy;
  37         pid_t   pid;
  38
  39         if (pipe(pipe_fd) == -1)
  40                 return (-1);
  41
  42         if ((*master = open("/dev/ptc", O_RDWR|O_NOCTTY)) == -1)
  43                 goto out;
  44
  45         if ((path = ttyname(*master)) == NULL)
  46                 goto out;
  47
  48         if (name != NULL)
  49                 strlcpy(name, path, TTY_NAME_MAX);
  50
  51         if ((slave = open(path, O_RDWR|O_NOCTTY)) == -1)
  52                 goto out;
  53
  54         switch (pid = fork()) {
  55         case -1:
  56                 goto out;
  57         case 0:
  58                 close(*master);
  59
  60                 close(pipe_fd[1]);
  61                 while (read(pipe_fd[0], &dummy, 1) == -1) {
  62                         if (errno != EINTR)
  63                                 break;
  64                 }
  65                 close(pipe_fd[0]);
  66
  67                 fd = open(_PATH_TTY, O_RDWR|O_NOCTTY);
  68                 if (fd >= 0) {
  69                         ioctl(fd, TIOCNOTTY, NULL);
  70                         close(fd);
  71                 }
  72
  73                 if (setsid() < 0)
  74                         fatal("setsid");
  75
  76                 fd = open(_PATH_TTY, O_RDWR|O_NOCTTY);
  77                 if (fd >= 0)
  78                         fatalx("open succeeded (failed to disconnect)");
  79
  80                 fd = open(path, O_RDWR);
  81                 if (fd < 0)
  82                         fatal("open failed");
  83                 close(fd);
  84
  85                 fd = open("/dev/tty", O_WRONLY);
  86                 if (fd < 0)
  87                         fatal("open failed");
  88                 close(fd);
  89
  90                 if (tio != NULL && tcsetattr(slave, TCSAFLUSH, tio) == -1)
  91                         fatal("tcsetattr failed");
  92                 if (ioctl(slave, TIOCSWINSZ, ws) == -1)
  93                         fatal("ioctl failed");
  94
  95                 dup2(slave, 0);
  96                 dup2(slave, 1);
  97                 dup2(slave, 2);
  98                 if (slave > 2)
  99                         close(slave);
 100
 101                 return (0);
 102         }
 103
 104         close(slave);
 105
 106         close(pipe_fd[0]);
 107         close(pipe_fd[1]);
 108         return (pid);
 109
 110 out:
 111         if (*master != -1)
 112                 close(*master);
 113         if (slave != -1)
 114                 close(slave);
 115
 116         close(pipe_fd[0]);
 117         close(pipe_fd[1]);
 118         return (-1);
 119 }