src/libs/bsd/pty.cpp

   1 /*
   2  * Copyright 2008, Ingo Weinhold, ingo_weinhold@gmx.de. All rights reserved.
   3  * Copyright 2010, Jérôme Duval, korli@users.berlios.de. All rights reserved.
   4  * Distributed under the terms of the MIT License.
   5  */
   6
   7 #include <pty.h>
   8
   9 #include <errno.h>
  10 #include <fcntl.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13
  14
  15 int
  16 openpty(int* _master, int* _slave, char* name, struct termios* termAttrs,
  17         struct winsize* windowSize)
  18 {
  19         int master = posix_openpt(O_RDWR);
  20         if (master < 0)
  21         return -1;
  22
  23         int slave;
  24         const char *ttyName;
  25         if (grantpt(master) != 0 || unlockpt(master) != 0
  26                 || (ttyName = ptsname(master)) == NULL
  27                 || (slave = open(ttyName, O_RDWR | O_NOCTTY)) < 0) {
  28                 close(master);
  29                 return -1;
  30         }
  31
  32         if ((termAttrs != NULL && tcsetattr(master, TCSANOW, termAttrs) != 0)
  33                 || (windowSize != NULL
  34                         && ioctl(master, TIOCSWINSZ, windowSize, sizeof(winsize)) != 0)) {
  35                 close(slave);
  36                 close(master);
  37                 return -1;
  38         }
  39
  40         *_master = master;
  41         *_slave = slave;
  42
  43         if (name != NULL)
  44                 strcpy(name, ttyName);
  45
  46         return 0;
  47 }
  48
  49
  50 int
  51 login_tty(int fd)
  52 {
  53         setsid();
  54
  55         if (ioctl(fd, TIOCSCTTY, NULL) != 0)
  56                 return -1;
  57
  58         dup2(fd, 0);
  59         dup2(fd, 1);
  60         dup2(fd, 2);
  61
  62         close(fd);
  63         return 0;
  64 }
  65
  66
  67 pid_t
  68 forkpty(int* _master, char* name, struct termios* termAttrs,
  69         struct winsize* windowSize)
  70 {
  71         int master, slave;
  72         if (openpty(&master, &slave, name, termAttrs, windowSize) != 0)
  73                 return -1;
  74
  75         int pid = fork();
  76         if (pid < 0) {
  77                 close(master);
  78                 close(slave);
  79                 return -1;
  80         }
  81         // child
  82         if (pid == 0) {
  83                 close(master);
  84                 return login_tty(slave);
  85         }
  86
  87         // parent
  88         close (slave);
  89         *_master = master;
  90         return pid;
  91 }