--- /dev/null
+"""Pseudo terminal utilities."""\r
+\r
+# Bugs: No signal handling. Doesn't set slave termios and window size.\r
+# Only tested on Linux.\r
+# See: W. Richard Stevens. 1992. Advanced Programming in the\r
+# UNIX Environment. Chapter 19.\r
+# Author: Steen Lumholt -- with additions by Guido.\r
+\r
+from select import select, error\r
+import os\r
+\r
+# Absurd: import termios and then delete it. This is to force an attempt\r
+# to import pty to raise an ImportError on platforms that lack termios.\r
+# Without this explicit import of termios here, some other module may\r
+# import tty first, which in turn imports termios and dies with an\r
+# ImportError then. But since tty *does* exist across platforms, that\r
+# leaves a damaged module object for tty in sys.modules, and the import\r
+# of tty here then appears to work despite that the tty imported is junk.\r
+import termios\r
+del termios\r
+\r
+import tty\r
+\r
+__all__ = ["openpty","fork","spawn","th_spawn","popen2"]\r
+\r
+STDIN_FILENO = 0\r
+STDOUT_FILENO = 1\r
+STDERR_FILENO = 2\r
+\r
+CHILD = 0\r
+\r
+def openpty():\r
+ """openpty() -> (master_fd, slave_fd)\r
+ Open a pty master/slave pair, using os.openpty() if possible."""\r
+\r
+ try:\r
+ return os.openpty()\r
+ except (AttributeError, OSError):\r
+ pass\r
+ master_fd, slave_name = _open_terminal()\r
+ slave_fd = slave_open(slave_name)\r
+ return master_fd, slave_fd\r
+\r
+def master_open():\r
+ """master_open() -> (master_fd, slave_name)\r
+ Open a pty master and return the fd, and the filename of the slave end.\r
+ Deprecated, use openpty() instead."""\r
+\r
+ try:\r
+ master_fd, slave_fd = os.openpty()\r
+ except (AttributeError, OSError):\r
+ pass\r
+ else:\r
+ slave_name = os.ttyname(slave_fd)\r
+ os.close(slave_fd)\r
+ return master_fd, slave_name\r
+\r
+ return _open_terminal()\r
+\r
+def _open_terminal():\r
+ """Open pty master and return (master_fd, tty_name).\r
+ SGI and generic BSD version, for when openpty() fails."""\r
+ try:\r
+ import sgi\r
+ except ImportError:\r
+ pass\r
+ else:\r
+ try:\r
+ tty_name, master_fd = sgi._getpty(os.O_RDWR, 0666, 0)\r
+ except IOError, msg:\r
+ raise os.error, msg\r
+ return master_fd, tty_name\r
+ for x in 'pqrstuvwxyzPQRST':\r
+ for y in '0123456789abcdef':\r
+ pty_name = '/dev/pty' + x + y\r
+ try:\r
+ fd = os.open(pty_name, os.O_RDWR)\r
+ except os.error:\r
+ continue\r
+ return (fd, '/dev/tty' + x + y)\r
+ raise os.error, 'out of pty devices'\r
+\r
+def slave_open(tty_name):\r
+ """slave_open(tty_name) -> slave_fd\r
+ Open the pty slave and acquire the controlling terminal, returning\r
+ opened filedescriptor.\r
+ Deprecated, use openpty() instead."""\r
+\r
+ return os.open(tty_name, os.O_RDWR)\r
+\r
+def fork():\r
+ """fork() -> (pid, master_fd)\r
+ Fork and make the child a session leader with a controlling terminal."""\r
+\r
+ try:\r
+ pid, fd = os.forkpty()\r
+ except (AttributeError, OSError):\r
+ pass\r
+ else:\r
+ if pid == CHILD:\r
+ try:\r
+ os.setsid()\r
+ except OSError:\r
+ # os.forkpty() already set us session leader\r
+ pass\r
+ return pid, fd\r
+\r
+ master_fd, slave_fd = openpty()\r
+ pid = os.fork()\r
+ if pid == CHILD:\r
+ # Establish a new session.\r
+ os.setsid()\r
+ os.close(master_fd)\r
+\r
+ # Slave becomes stdin/stdout/stderr of child.\r
+ os.dup2(slave_fd, STDIN_FILENO)\r
+ os.dup2(slave_fd, STDOUT_FILENO)\r
+ os.dup2(slave_fd, STDERR_FILENO)\r
+ if (slave_fd > STDERR_FILENO):\r
+ os.close (slave_fd)\r
+\r
+ # Parent and child process.\r
+ return pid, master_fd\r
+\r
+def _writen(fd, data):\r
+ """Write all the data to a descriptor."""\r
+ while data != '':\r
+ n = os.write(fd, data)\r
+ data = data[n:]\r
+\r
+def _read(fd):\r
+ """Default read function."""\r
+ return os.read(fd, 1024)\r
+\r
+def _copy(master_fd, master_read=_read, stdin_read=_read, stdin_fd=STDIN_FILENO,\r
+ stdout_fd=STDOUT_FILENO):\r
+ """Parent copy loop.\r
+ Copies\r
+ pty master -> stdout_fd (master_read)\r
+ stdin_fd -> pty master (stdin_read)"""\r
+ try:\r
+ mode = tty.tcgetattr(stdin_fd)\r
+ tty.setraw(stdin_fd)\r
+ restore = 1\r
+ except tty.error: # This is the same as termios.error\r
+ restore = 0\r
+ try:\r
+ while 1:\r
+ rfds, wfds, xfds = select(\r
+ [master_fd, stdin_fd], [], [])\r
+ if master_fd in rfds:\r
+ data = master_read(master_fd)\r
+ os.write(stdout_fd, data)\r
+ if stdin_fd in rfds:\r
+ data = stdin_read(stdin_fd)\r
+ _writen(master_fd, data)\r
+ except (IOError, OSError, error): # The last entry is select.error\r
+ if restore:\r
+ tty.tcsetattr(stdin_fd, tty.TCSAFLUSH, mode)\r
+ if stdin_fd > STDERR_FILENO:\r
+ os.close(stdin_fd)\r
+ if stdout_fd > STDERR_FILENO:\r
+ os.close(stdout_fd)\r
+\r
+def spawn(argv, master_read=_read, stdin_read=_read, stdin_fd=STDIN_FILENO,\r
+ stdout_fd=STDOUT_FILENO):\r
+ """Create a spawned process. The controlling terminal reads and\r
+ writes its data to stdin_fd and stdout_fd respectively.\r
+ \r
+ NOTE: This function does not return until one of the input or output file\r
+ descriptors are closed, or the child process exits."""\r
+ if type(argv) == type(''):\r
+ argv = (argv,)\r
+ pid, master_fd = fork()\r
+ if pid == CHILD:\r
+ apply(os.execlp, (argv[0],) + argv)\r
+ _copy(master_fd, master_read, stdin_read, stdin_fd, stdout_fd)\r
+\r
+def th_spawn(argv, master_read=_read, stdin_read=_read, stdin_fd=STDIN_FILENO,\r
+ stdout_fd=STDOUT_FILENO):\r
+ """Create a spawned process. The controlling terminal reads and\r
+ writes its data to stdin_fd and stdout_fd respectively. The function\r
+ returns the pid of the spawned process. (It returns immediately.)"""\r
+ import thread\r
+ if type(argv) == type(''):\r
+ argv = (argv,)\r
+ pid, master_fd = fork()\r
+ if pid == CHILD:\r
+ apply(os.execlp, (argv[0],) + argv)\r
+ thread.start_new_thread(_copy, (master_fd, master_read, stdin_read, \\r
+ stdin_fd, stdout_fd))\r
+ return pid\r
+\r
+def popen2(cmd, bufsize=1024, master_read=_read, stdin_read=_read):\r
+ """Execute the shell command 'cmd' in a sub-process.\r
+ \r
+ If 'bufsize' is specified, it sets the buffer size for the I/O pipes.\r
+ The function returns (child_stdin, child_stdout, child_pid), where the\r
+ file objects are pipes connected to the spawned process's controling\r
+ terminal, and the child_pid is the pid of the child process.\r
+ """\r
+ argv = ('/bin/sh', '-c', cmd)\r
+ child_stdin_rfd, child_stdin_wfd = os.pipe()\r
+ child_stdout_rfd, child_stdout_wfd = os.pipe()\r
+ child_pid = th_spawn(argv, master_read, stdin_read, child_stdin_rfd, \\r
+ child_stdout_wfd)\r
+ child_stdin = os.fdopen(child_stdin_wfd, 'w', bufsize)\r
+ child_stdout = os.fdopen(child_stdout_rfd, 'r', bufsize)\r
+ return child_stdin, child_stdout, child_pid\r
git://git.onelab.eu / monitor.git / blobdiff