Guido van Rossum | 54f22ed | 2000-02-04 15:10:34 +0000 | [diff] [blame] | 1 | """Pseudo terminal utilities.""" |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 2 | |
| 3 | # Bugs: No signal handling. Doesn't set slave termios and window size. |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 4 | # Only tested on Linux. |
| 5 | # See: W. Richard Stevens. 1992. Advanced Programming in the |
| 6 | # UNIX Environment. Chapter 19. |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 7 | # Author: Steen Lumholt -- with additions by Guido. |
| 8 | |
| 9 | from select import select |
Fred Drake | 66aaaae | 2001-05-10 05:17:02 +0000 | [diff] [blame] | 10 | import os |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 11 | import tty |
| 12 | |
Skip Montanaro | c62c81e | 2001-02-12 02:00:42 +0000 | [diff] [blame] | 13 | __all__ = ["openpty","fork","spawn"] |
| 14 | |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 15 | STDIN_FILENO = 0 |
| 16 | STDOUT_FILENO = 1 |
| 17 | STDERR_FILENO = 2 |
| 18 | |
| 19 | CHILD = 0 |
| 20 | |
Fred Drake | 8cef4cf | 2000-06-28 16:40:38 +0000 | [diff] [blame] | 21 | def openpty(): |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 22 | """openpty() -> (master_fd, slave_fd) |
| 23 | Open a pty master/slave pair, using os.openpty() if possible.""" |
Fred Drake | 8cef4cf | 2000-06-28 16:40:38 +0000 | [diff] [blame] | 24 | |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 25 | try: |
| 26 | return os.openpty() |
| 27 | except (AttributeError, OSError): |
| 28 | pass |
| 29 | master_fd, slave_name = _open_terminal() |
| 30 | slave_fd = slave_open(slave_name) |
| 31 | return master_fd, slave_fd |
Fred Drake | 8cef4cf | 2000-06-28 16:40:38 +0000 | [diff] [blame] | 32 | |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 33 | def master_open(): |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 34 | """master_open() -> (master_fd, slave_name) |
| 35 | Open a pty master and return the fd, and the filename of the slave end. |
| 36 | Deprecated, use openpty() instead.""" |
Fred Drake | 8cef4cf | 2000-06-28 16:40:38 +0000 | [diff] [blame] | 37 | |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 38 | try: |
| 39 | master_fd, slave_fd = os.openpty() |
| 40 | except (AttributeError, OSError): |
| 41 | pass |
| 42 | else: |
| 43 | slave_name = os.ttyname(slave_fd) |
| 44 | os.close(slave_fd) |
| 45 | return master_fd, slave_name |
Fred Drake | 8cef4cf | 2000-06-28 16:40:38 +0000 | [diff] [blame] | 46 | |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 47 | return _open_terminal() |
Fred Drake | 8cef4cf | 2000-06-28 16:40:38 +0000 | [diff] [blame] | 48 | |
| 49 | def _open_terminal(): |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 50 | """Open pty master and return (master_fd, tty_name). |
| 51 | SGI and generic BSD version, for when openpty() fails.""" |
| 52 | try: |
| 53 | import sgi |
| 54 | except ImportError: |
| 55 | pass |
| 56 | else: |
| 57 | try: |
Guido van Rossum | cd16bf6 | 2007-06-13 18:07:49 +0000 | [diff] [blame] | 58 | tty_name, master_fd = sgi._getpty(os.O_RDWR, 0o666, 0) |
Guido van Rossum | b940e11 | 2007-01-10 16:19:56 +0000 | [diff] [blame] | 59 | except IOError as msg: |
Collin Winter | ce36ad8 | 2007-08-30 01:19:48 +0000 | [diff] [blame] | 60 | raise os.error(msg) |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 61 | return master_fd, tty_name |
| 62 | for x in 'pqrstuvwxyzPQRST': |
| 63 | for y in '0123456789abcdef': |
| 64 | pty_name = '/dev/pty' + x + y |
| 65 | try: |
Fred Drake | 66aaaae | 2001-05-10 05:17:02 +0000 | [diff] [blame] | 66 | fd = os.open(pty_name, os.O_RDWR) |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 67 | except os.error: |
| 68 | continue |
| 69 | return (fd, '/dev/tty' + x + y) |
Collin Winter | ce36ad8 | 2007-08-30 01:19:48 +0000 | [diff] [blame] | 70 | raise os.error('out of pty devices') |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 71 | |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 72 | def slave_open(tty_name): |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 73 | """slave_open(tty_name) -> slave_fd |
| 74 | Open the pty slave and acquire the controlling terminal, returning |
| 75 | opened filedescriptor. |
| 76 | Deprecated, use openpty() instead.""" |
Fred Drake | 8cef4cf | 2000-06-28 16:40:38 +0000 | [diff] [blame] | 77 | |
Martin v. Löwis | 14e73b1 | 2003-01-01 09:51:12 +0000 | [diff] [blame] | 78 | result = os.open(tty_name, os.O_RDWR) |
| 79 | try: |
| 80 | from fcntl import ioctl, I_PUSH |
| 81 | except ImportError: |
| 82 | return result |
| 83 | try: |
Tim Peters | 2c60f7a | 2003-01-29 03:49:43 +0000 | [diff] [blame] | 84 | ioctl(result, I_PUSH, "ptem") |
| 85 | ioctl(result, I_PUSH, "ldterm") |
Martin v. Löwis | 14e73b1 | 2003-01-01 09:51:12 +0000 | [diff] [blame] | 86 | except IOError: |
| 87 | pass |
| 88 | return result |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 89 | |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 90 | def fork(): |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 91 | """fork() -> (pid, master_fd) |
| 92 | Fork and make the child a session leader with a controlling terminal.""" |
Fred Drake | 8cef4cf | 2000-06-28 16:40:38 +0000 | [diff] [blame] | 93 | |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 94 | try: |
| 95 | pid, fd = os.forkpty() |
| 96 | except (AttributeError, OSError): |
| 97 | pass |
| 98 | else: |
| 99 | if pid == CHILD: |
| 100 | try: |
| 101 | os.setsid() |
| 102 | except OSError: |
| 103 | # os.forkpty() already set us session leader |
| 104 | pass |
| 105 | return pid, fd |
Fred Drake | 8cef4cf | 2000-06-28 16:40:38 +0000 | [diff] [blame] | 106 | |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 107 | master_fd, slave_fd = openpty() |
| 108 | pid = os.fork() |
| 109 | if pid == CHILD: |
| 110 | # Establish a new session. |
| 111 | os.setsid() |
| 112 | os.close(master_fd) |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 113 | |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 114 | # Slave becomes stdin/stdout/stderr of child. |
| 115 | os.dup2(slave_fd, STDIN_FILENO) |
| 116 | os.dup2(slave_fd, STDOUT_FILENO) |
| 117 | os.dup2(slave_fd, STDERR_FILENO) |
| 118 | if (slave_fd > STDERR_FILENO): |
| 119 | os.close (slave_fd) |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 120 | |
Thomas Wouters | 89f507f | 2006-12-13 04:49:30 +0000 | [diff] [blame] | 121 | # Explicitly open the tty to make it become a controlling tty. |
| 122 | tmp_fd = os.open(os.ttyname(STDOUT_FILENO), os.O_RDWR) |
| 123 | os.close(tmp_fd) |
Thomas Wouters | 902d6eb | 2007-01-09 23:18:33 +0000 | [diff] [blame] | 124 | else: |
| 125 | os.close(slave_fd) |
Thomas Wouters | 9fe394c | 2007-02-05 01:24:16 +0000 | [diff] [blame] | 126 | |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 127 | # Parent and child process. |
| 128 | return pid, master_fd |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 129 | |
Fred Drake | 8cef4cf | 2000-06-28 16:40:38 +0000 | [diff] [blame] | 130 | def _writen(fd, data): |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 131 | """Write all the data to a descriptor.""" |
Antoine Pitrou | 9cadb1b | 2008-09-15 23:02:56 +0000 | [diff] [blame] | 132 | while data: |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 133 | n = os.write(fd, data) |
| 134 | data = data[n:] |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 135 | |
Fred Drake | 8cef4cf | 2000-06-28 16:40:38 +0000 | [diff] [blame] | 136 | def _read(fd): |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 137 | """Default read function.""" |
| 138 | return os.read(fd, 1024) |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 139 | |
Fred Drake | 8cef4cf | 2000-06-28 16:40:38 +0000 | [diff] [blame] | 140 | def _copy(master_fd, master_read=_read, stdin_read=_read): |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 141 | """Parent copy loop. |
| 142 | Copies |
| 143 | pty master -> standard output (master_read) |
| 144 | standard input -> pty master (stdin_read)""" |
Gregory P. Smith | 05f5953 | 2012-02-16 00:29:12 -0800 | [diff] [blame] | 145 | fds = [master_fd, STDIN_FILENO] |
| 146 | while True: |
| 147 | rfds, wfds, xfds = select(fds, [], []) |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 148 | if master_fd in rfds: |
| 149 | data = master_read(master_fd) |
Gregory P. Smith | 05f5953 | 2012-02-16 00:29:12 -0800 | [diff] [blame] | 150 | if not data: # Reached EOF. |
| 151 | fds.remove(master_fd) |
| 152 | else: |
| 153 | os.write(STDOUT_FILENO, data) |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 154 | if STDIN_FILENO in rfds: |
| 155 | data = stdin_read(STDIN_FILENO) |
Gregory P. Smith | 05f5953 | 2012-02-16 00:29:12 -0800 | [diff] [blame] | 156 | if not data: |
| 157 | fds.remove(STDIN_FILENO) |
| 158 | else: |
| 159 | _writen(master_fd, data) |
Guido van Rossum | 23cb2a8 | 1994-09-12 10:36:35 +0000 | [diff] [blame] | 160 | |
Fred Drake | 8cef4cf | 2000-06-28 16:40:38 +0000 | [diff] [blame] | 161 | def spawn(argv, master_read=_read, stdin_read=_read): |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 162 | """Create a spawned process.""" |
| 163 | if type(argv) == type(''): |
| 164 | argv = (argv,) |
| 165 | pid, master_fd = fork() |
| 166 | if pid == CHILD: |
Guido van Rossum | 68468eb | 2003-02-27 20:14:51 +0000 | [diff] [blame] | 167 | os.execlp(argv[0], *argv) |
Martin v. Löwis | 6c611fa | 2002-07-28 09:42:57 +0000 | [diff] [blame] | 168 | try: |
| 169 | mode = tty.tcgetattr(STDIN_FILENO) |
| 170 | tty.setraw(STDIN_FILENO) |
| 171 | restore = 1 |
| 172 | except tty.error: # This is the same as termios.error |
| 173 | restore = 0 |
Tim Peters | 2344fae | 2001-01-15 00:50:52 +0000 | [diff] [blame] | 174 | try: |
| 175 | _copy(master_fd, master_read, stdin_read) |
Martin v. Löwis | 6c611fa | 2002-07-28 09:42:57 +0000 | [diff] [blame] | 176 | except (IOError, OSError): |
| 177 | if restore: |
| 178 | tty.tcsetattr(STDIN_FILENO, tty.TCSAFLUSH, mode) |
Andrew M. Kuchling | a2c9a98 | 2004-06-05 16:27:16 +0000 | [diff] [blame] | 179 | |
| 180 | os.close(master_fd) |
Gregory P. Smith | 0f21adf7 | 2012-09-29 12:41:03 -0700 | [diff] [blame] | 181 | return os.waitpid(pid, 0)[1] |