# Copyright 2010-2011 Gentoo Foundation # Distributed under the terms of the GNU General Public License v2 import platform import pty import termios from portage import os from portage.output import get_term_size, set_term_size from portage.util import writemsg # Disable the use of openpty on Solaris as it seems Python's openpty # implementation doesn't play nice on Solaris with Portage's # behaviour causing hangs/deadlocks. # Additional note for the future: on Interix, pipes do NOT work, so # _disable_openpty on Interix must *never* be True _disable_openpty = platform.system() in ("SunOS",) _fbsd_test_pty = platform.system() == 'FreeBSD' def _create_pty_or_pipe(copy_term_size=None): """ Try to create a pty and if then fails then create a normal pipe instead. @param copy_term_size: If a tty file descriptor is given then the term size will be copied to the pty. @type copy_term_size: int @rtype: tuple @return: A tuple of (is_pty, master_fd, slave_fd) where is_pty is True if a pty was successfully allocated, and False if a normal pipe was allocated. """ got_pty = False global _disable_openpty, _fbsd_test_pty if _fbsd_test_pty and not _disable_openpty: # Test for python openpty breakage after freebsd7 to freebsd8 # upgrade, which results in a 'Function not implemented' error # and the process being killed. pid = os.fork() if pid == 0: pty.openpty() os._exit(os.EX_OK) pid, status = os.waitpid(pid, 0) if (status & 0xff) == 140: _disable_openpty = True _fbsd_test_pty = False if _disable_openpty: master_fd, slave_fd = os.pipe() else: try: master_fd, slave_fd = pty.openpty() got_pty = True except EnvironmentError as e: _disable_openpty = True writemsg("openpty failed: '%s'\n" % str(e), noiselevel=-1) del e master_fd, slave_fd = os.pipe() if got_pty: # Disable post-processing of output since otherwise weird # things like \n -> \r\n transformations may occur. mode = termios.tcgetattr(slave_fd) mode[1] &= ~termios.OPOST termios.tcsetattr(slave_fd, termios.TCSANOW, mode) if got_pty and \ copy_term_size is not None and \ os.isatty(copy_term_size): rows, columns = get_term_size() set_term_size(rows, columns, slave_fd) return (got_pty, master_fd, slave_fd)