1345 lines
49 KiB
Python
1345 lines
49 KiB
Python
# subprocess - Subprocesses with accessible I/O streams
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#
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# For more information about this module, see PEP 324.
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#
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# Copyright (c) 2003-2005 by Peter Astrand <astrand@lysator.liu.se>
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#
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# Licensed to PSF under a Contributor Agreement.
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# See http://www.python.org/2.4/license for licensing details.
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r"""Subprocesses with accessible I/O streams
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This module allows you to spawn processes, connect to their
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input/output/error pipes, and obtain their return codes.
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For a complete description of this module see the Python documentation.
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Main API
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========
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call(...): Runs a command, waits for it to complete, then returns
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the return code.
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check_call(...): Same as call() but raises CalledProcessError()
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if return code is not 0
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check_output(...): Same as check_call() but returns the contents of
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stdout instead of a return code
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Popen(...): A class for flexibly executing a command in a new process
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Constants
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---------
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PIPE: Special value that indicates a pipe should be created
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STDOUT: Special value that indicates that stderr should go to stdout
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"""
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import sys
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mswindows = (sys.platform == "win32")
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import os
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import types
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import traceback
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import gc
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import signal
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import errno
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# Exception classes used by this module.
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class CalledProcessError(Exception):
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"""This exception is raised when a process run by check_call() or
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check_output() returns a non-zero exit status.
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Attributes:
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cmd, returncode, output
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"""
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def __init__(self, returncode, cmd, output=None):
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self.returncode = returncode
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self.cmd = cmd
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self.output = output
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def __str__(self):
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return "Command '%s' returned non-zero exit status %d" % (self.cmd, self.returncode)
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if mswindows:
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import threading
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import msvcrt
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import _subprocess
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class STARTUPINFO:
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dwFlags = 0
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hStdInput = None
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hStdOutput = None
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hStdError = None
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wShowWindow = 0
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class pywintypes:
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error = IOError
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else:
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import select
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_has_poll = hasattr(select, 'poll')
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try:
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import threading
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except ImportError:
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threading = None
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import fcntl
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import pickle
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# When select or poll has indicated that the file is writable,
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# we can write up to _PIPE_BUF bytes without risk of blocking.
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# POSIX defines PIPE_BUF as >= 512.
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_PIPE_BUF = getattr(select, 'PIPE_BUF', 512)
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__all__ = ["Popen", "PIPE", "STDOUT", "call", "check_call",
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"check_output", "CalledProcessError"]
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if mswindows:
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from _subprocess import (CREATE_NEW_CONSOLE, CREATE_NEW_PROCESS_GROUP,
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STD_INPUT_HANDLE, STD_OUTPUT_HANDLE,
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STD_ERROR_HANDLE, SW_HIDE,
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STARTF_USESTDHANDLES, STARTF_USESHOWWINDOW)
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__all__.extend(["CREATE_NEW_CONSOLE", "CREATE_NEW_PROCESS_GROUP",
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"STD_INPUT_HANDLE", "STD_OUTPUT_HANDLE",
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"STD_ERROR_HANDLE", "SW_HIDE",
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"STARTF_USESTDHANDLES", "STARTF_USESHOWWINDOW"])
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try:
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MAXFD = os.sysconf("SC_OPEN_MAX")
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except:
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MAXFD = 256
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_active = []
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def _cleanup():
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for inst in _active[:]:
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res = inst._internal_poll(_deadstate=sys.maxint)
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if res is not None:
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try:
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_active.remove(inst)
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except ValueError:
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# This can happen if two threads create a new Popen instance.
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# It's harmless that it was already removed, so ignore.
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pass
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PIPE = -1
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STDOUT = -2
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def _eintr_retry_call(func, *args):
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while True:
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try:
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return func(*args)
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except (OSError, IOError) as e:
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if e.errno == errno.EINTR:
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continue
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raise
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# XXX This function is only used by multiprocessing and the test suite,
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# but it's here so that it can be imported when Python is compiled without
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# threads.
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def _args_from_interpreter_flags():
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"""Return a list of command-line arguments reproducing the current
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settings in sys.flags and sys.warnoptions."""
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flag_opt_map = {
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'debug': 'd',
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# 'inspect': 'i',
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# 'interactive': 'i',
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'optimize': 'O',
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'dont_write_bytecode': 'B',
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'no_user_site': 's',
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'no_site': 'S',
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'ignore_environment': 'E',
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'verbose': 'v',
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'bytes_warning': 'b',
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'py3k_warning': '3',
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}
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args = []
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for flag, opt in flag_opt_map.items():
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v = getattr(sys.flags, flag)
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if v > 0:
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args.append('-' + opt * v)
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if getattr(sys.flags, 'hash_randomization') != 0:
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args.append('-R')
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for opt in sys.warnoptions:
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args.append('-W' + opt)
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return args
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def call(*popenargs, **kwargs):
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"""Run command with arguments. Wait for command to complete, then
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return the returncode attribute.
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The arguments are the same as for the Popen constructor. Example:
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retcode = call(["ls", "-l"])
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"""
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return Popen(*popenargs, **kwargs).wait()
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def check_call(*popenargs, **kwargs):
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"""Run command with arguments. Wait for command to complete. If
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the exit code was zero then return, otherwise raise
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CalledProcessError. The CalledProcessError object will have the
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return code in the returncode attribute.
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The arguments are the same as for the Popen constructor. Example:
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check_call(["ls", "-l"])
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"""
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retcode = call(*popenargs, **kwargs)
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if retcode:
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cmd = kwargs.get("args")
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if cmd is None:
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cmd = popenargs[0]
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raise CalledProcessError(retcode, cmd)
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return 0
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def check_output(*popenargs, **kwargs):
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r"""Run command with arguments and return its output as a byte string.
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If the exit code was non-zero it raises a CalledProcessError. The
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CalledProcessError object will have the return code in the returncode
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attribute and output in the output attribute.
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The arguments are the same as for the Popen constructor. Example:
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>>> check_output(["ls", "-l", "/dev/null"])
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'crw-rw-rw- 1 root root 1, 3 Oct 18 2007 /dev/null\n'
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The stdout argument is not allowed as it is used internally.
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To capture standard error in the result, use stderr=STDOUT.
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>>> check_output(["/bin/sh", "-c",
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... "ls -l non_existent_file ; exit 0"],
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... stderr=STDOUT)
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'ls: non_existent_file: No such file or directory\n'
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"""
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if 'stdout' in kwargs:
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raise ValueError('stdout argument not allowed, it will be overridden.')
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process = Popen(stdout=PIPE, *popenargs, **kwargs)
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output, unused_err = process.communicate()
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retcode = process.poll()
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if retcode:
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cmd = kwargs.get("args")
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if cmd is None:
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cmd = popenargs[0]
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raise CalledProcessError(retcode, cmd, output=output)
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return output
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def list2cmdline(seq):
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"""
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Translate a sequence of arguments into a command line
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string, using the same rules as the MS C runtime:
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1) Arguments are delimited by white space, which is either a
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space or a tab.
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2) A string surrounded by double quotation marks is
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interpreted as a single argument, regardless of white space
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contained within. A quoted string can be embedded in an
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argument.
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3) A double quotation mark preceded by a backslash is
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interpreted as a literal double quotation mark.
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4) Backslashes are interpreted literally, unless they
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immediately precede a double quotation mark.
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5) If backslashes immediately precede a double quotation mark,
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every pair of backslashes is interpreted as a literal
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backslash. If the number of backslashes is odd, the last
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backslash escapes the next double quotation mark as
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described in rule 3.
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"""
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# See
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# http://msdn.microsoft.com/en-us/library/17w5ykft.aspx
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# or search http://msdn.microsoft.com for
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# "Parsing C++ Command-Line Arguments"
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result = []
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needquote = False
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for arg in seq:
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bs_buf = []
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# Add a space to separate this argument from the others
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if result:
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result.append(' ')
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needquote = (" " in arg) or ("\t" in arg) or not arg
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if needquote:
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result.append('"')
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for c in arg:
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if c == '\\':
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# Don't know if we need to double yet.
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bs_buf.append(c)
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elif c == '"':
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# Double backslashes.
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result.append('\\' * len(bs_buf)*2)
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bs_buf = []
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result.append('\\"')
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else:
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# Normal char
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if bs_buf:
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result.extend(bs_buf)
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bs_buf = []
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result.append(c)
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# Add remaining backslashes, if any.
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if bs_buf:
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result.extend(bs_buf)
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if needquote:
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result.extend(bs_buf)
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result.append('"')
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return ''.join(result)
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class Popen(object):
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""" Execute a child program in a new process.
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For a complete description of the arguments see the Python documentation.
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Arguments:
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args: A string, or a sequence of program arguments.
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bufsize: supplied as the buffering argument to the open() function when
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creating the stdin/stdout/stderr pipe file objects
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executable: A replacement program to execute.
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stdin, stdout and stderr: These specify the executed programs' standard
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input, standard output and standard error file handles, respectively.
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preexec_fn: (POSIX only) An object to be called in the child process
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just before the child is executed.
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close_fds: Controls closing or inheriting of file descriptors.
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shell: If true, the command will be executed through the shell.
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cwd: Sets the current directory before the child is executed.
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env: Defines the environment variables for the new process.
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universal_newlines: If true, use universal line endings for file
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objects stdin, stdout and stderr.
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startupinfo and creationflags (Windows only)
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Attributes:
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stdin, stdout, stderr, pid, returncode
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"""
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_child_created = False # Set here since __del__ checks it
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def __init__(self, args, bufsize=0, executable=None,
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stdin=None, stdout=None, stderr=None,
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preexec_fn=None, close_fds=False, shell=False,
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cwd=None, env=None, universal_newlines=False,
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startupinfo=None, creationflags=0):
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"""Create new Popen instance."""
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_cleanup()
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if not isinstance(bufsize, (int, long)):
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raise TypeError("bufsize must be an integer")
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if mswindows:
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if preexec_fn is not None:
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raise ValueError("preexec_fn is not supported on Windows "
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"platforms")
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if close_fds and (stdin is not None or stdout is not None or
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stderr is not None):
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raise ValueError("close_fds is not supported on Windows "
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"platforms if you redirect stdin/stdout/stderr")
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else:
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# POSIX
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if startupinfo is not None:
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raise ValueError("startupinfo is only supported on Windows "
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"platforms")
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if creationflags != 0:
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raise ValueError("creationflags is only supported on Windows "
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"platforms")
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self.stdin = None
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self.stdout = None
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self.stderr = None
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self.pid = None
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self.returncode = None
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self.universal_newlines = universal_newlines
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# Input and output objects. The general principle is like
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# this:
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#
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# Parent Child
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# ------ -----
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# p2cwrite ---stdin---> p2cread
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# c2pread <--stdout--- c2pwrite
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# errread <--stderr--- errwrite
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#
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# On POSIX, the child objects are file descriptors. On
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# Windows, these are Windows file handles. The parent objects
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# are file descriptors on both platforms. The parent objects
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# are None when not using PIPEs. The child objects are None
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# when not redirecting.
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(p2cread, p2cwrite,
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c2pread, c2pwrite,
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errread, errwrite), to_close = self._get_handles(stdin, stdout, stderr)
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try:
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self._execute_child(args, executable, preexec_fn, close_fds,
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cwd, env, universal_newlines,
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startupinfo, creationflags, shell, to_close,
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p2cread, p2cwrite,
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c2pread, c2pwrite,
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errread, errwrite)
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except Exception:
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# Preserve original exception in case os.close raises.
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exc_type, exc_value, exc_trace = sys.exc_info()
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for fd in to_close:
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try:
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if mswindows:
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fd.Close()
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else:
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os.close(fd)
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except EnvironmentError:
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pass
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raise exc_type, exc_value, exc_trace
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if mswindows:
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if p2cwrite is not None:
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p2cwrite = msvcrt.open_osfhandle(p2cwrite.Detach(), 0)
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if c2pread is not None:
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c2pread = msvcrt.open_osfhandle(c2pread.Detach(), 0)
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if errread is not None:
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errread = msvcrt.open_osfhandle(errread.Detach(), 0)
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if p2cwrite is not None:
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self.stdin = os.fdopen(p2cwrite, 'wb', bufsize)
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if c2pread is not None:
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if universal_newlines:
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self.stdout = os.fdopen(c2pread, 'rU', bufsize)
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else:
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self.stdout = os.fdopen(c2pread, 'rb', bufsize)
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if errread is not None:
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if universal_newlines:
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self.stderr = os.fdopen(errread, 'rU', bufsize)
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else:
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self.stderr = os.fdopen(errread, 'rb', bufsize)
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|
|
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def _translate_newlines(self, data):
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data = data.replace("\r\n", "\n")
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data = data.replace("\r", "\n")
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return data
|
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|
|
|
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def __del__(self, _maxint=sys.maxint):
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# If __init__ hasn't had a chance to execute (e.g. if it
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# was passed an undeclared keyword argument), we don't
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# have a _child_created attribute at all.
|
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if not self._child_created:
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# We didn't get to successfully create a child process.
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return
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# In case the child hasn't been waited on, check if it's done.
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self._internal_poll(_deadstate=_maxint)
|
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if self.returncode is None and _active is not None:
|
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# Child is still running, keep us alive until we can wait on it.
|
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_active.append(self)
|
|
|
|
|
|
def communicate(self, input=None):
|
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"""Interact with process: Send data to stdin. Read data from
|
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stdout and stderr, until end-of-file is reached. Wait for
|
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process to terminate. The optional input argument should be a
|
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string to be sent to the child process, or None, if no data
|
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should be sent to the child.
|
|
|
|
communicate() returns a tuple (stdout, stderr)."""
|
|
|
|
# Optimization: If we are only using one pipe, or no pipe at
|
|
# all, using select() or threads is unnecessary.
|
|
if [self.stdin, self.stdout, self.stderr].count(None) >= 2:
|
|
stdout = None
|
|
stderr = None
|
|
if self.stdin:
|
|
if input:
|
|
try:
|
|
self.stdin.write(input)
|
|
except IOError as e:
|
|
if e.errno != errno.EPIPE and e.errno != errno.EINVAL:
|
|
raise
|
|
self.stdin.close()
|
|
elif self.stdout:
|
|
stdout = _eintr_retry_call(self.stdout.read)
|
|
self.stdout.close()
|
|
elif self.stderr:
|
|
stderr = _eintr_retry_call(self.stderr.read)
|
|
self.stderr.close()
|
|
self.wait()
|
|
return (stdout, stderr)
|
|
|
|
return self._communicate(input)
|
|
|
|
|
|
def poll(self):
|
|
"""Check if child process has terminated. Set and return returncode
|
|
attribute."""
|
|
return self._internal_poll()
|
|
|
|
|
|
if mswindows:
|
|
#
|
|
# Windows methods
|
|
#
|
|
def _get_handles(self, stdin, stdout, stderr):
|
|
"""Construct and return tuple with IO objects:
|
|
p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite
|
|
"""
|
|
to_close = set()
|
|
if stdin is None and stdout is None and stderr is None:
|
|
return (None, None, None, None, None, None), to_close
|
|
|
|
p2cread, p2cwrite = None, None
|
|
c2pread, c2pwrite = None, None
|
|
errread, errwrite = None, None
|
|
|
|
if stdin is None:
|
|
p2cread = _subprocess.GetStdHandle(_subprocess.STD_INPUT_HANDLE)
|
|
if p2cread is None:
|
|
p2cread, _ = _subprocess.CreatePipe(None, 0)
|
|
elif stdin == PIPE:
|
|
p2cread, p2cwrite = _subprocess.CreatePipe(None, 0)
|
|
elif isinstance(stdin, (int, long)):
|
|
p2cread = msvcrt.get_osfhandle(stdin)
|
|
else:
|
|
# Assuming file-like object
|
|
p2cread = msvcrt.get_osfhandle(stdin.fileno())
|
|
p2cread = self._make_inheritable(p2cread)
|
|
# We just duplicated the handle, it has to be closed at the end
|
|
to_close.add(p2cread)
|
|
if stdin == PIPE:
|
|
to_close.add(p2cwrite)
|
|
|
|
if stdout is None:
|
|
c2pwrite = _subprocess.GetStdHandle(_subprocess.STD_OUTPUT_HANDLE)
|
|
if c2pwrite is None:
|
|
_, c2pwrite = _subprocess.CreatePipe(None, 0)
|
|
elif stdout == PIPE:
|
|
c2pread, c2pwrite = _subprocess.CreatePipe(None, 0)
|
|
elif isinstance(stdout, (int, long)):
|
|
c2pwrite = msvcrt.get_osfhandle(stdout)
|
|
else:
|
|
# Assuming file-like object
|
|
c2pwrite = msvcrt.get_osfhandle(stdout.fileno())
|
|
c2pwrite = self._make_inheritable(c2pwrite)
|
|
# We just duplicated the handle, it has to be closed at the end
|
|
to_close.add(c2pwrite)
|
|
if stdout == PIPE:
|
|
to_close.add(c2pread)
|
|
|
|
if stderr is None:
|
|
errwrite = _subprocess.GetStdHandle(_subprocess.STD_ERROR_HANDLE)
|
|
if errwrite is None:
|
|
_, errwrite = _subprocess.CreatePipe(None, 0)
|
|
elif stderr == PIPE:
|
|
errread, errwrite = _subprocess.CreatePipe(None, 0)
|
|
elif stderr == STDOUT:
|
|
errwrite = c2pwrite
|
|
elif isinstance(stderr, (int, long)):
|
|
errwrite = msvcrt.get_osfhandle(stderr)
|
|
else:
|
|
# Assuming file-like object
|
|
errwrite = msvcrt.get_osfhandle(stderr.fileno())
|
|
errwrite = self._make_inheritable(errwrite)
|
|
# We just duplicated the handle, it has to be closed at the end
|
|
to_close.add(errwrite)
|
|
if stderr == PIPE:
|
|
to_close.add(errread)
|
|
|
|
return (p2cread, p2cwrite,
|
|
c2pread, c2pwrite,
|
|
errread, errwrite), to_close
|
|
|
|
|
|
def _make_inheritable(self, handle):
|
|
"""Return a duplicate of handle, which is inheritable"""
|
|
return _subprocess.DuplicateHandle(_subprocess.GetCurrentProcess(),
|
|
handle, _subprocess.GetCurrentProcess(), 0, 1,
|
|
_subprocess.DUPLICATE_SAME_ACCESS)
|
|
|
|
|
|
def _find_w9xpopen(self):
|
|
"""Find and return absolut path to w9xpopen.exe"""
|
|
w9xpopen = os.path.join(
|
|
os.path.dirname(_subprocess.GetModuleFileName(0)),
|
|
"w9xpopen.exe")
|
|
if not os.path.exists(w9xpopen):
|
|
# Eeek - file-not-found - possibly an embedding
|
|
# situation - see if we can locate it in sys.exec_prefix
|
|
w9xpopen = os.path.join(os.path.dirname(sys.exec_prefix),
|
|
"w9xpopen.exe")
|
|
if not os.path.exists(w9xpopen):
|
|
raise RuntimeError("Cannot locate w9xpopen.exe, which is "
|
|
"needed for Popen to work with your "
|
|
"shell or platform.")
|
|
return w9xpopen
|
|
|
|
|
|
def _execute_child(self, args, executable, preexec_fn, close_fds,
|
|
cwd, env, universal_newlines,
|
|
startupinfo, creationflags, shell, to_close,
|
|
p2cread, p2cwrite,
|
|
c2pread, c2pwrite,
|
|
errread, errwrite):
|
|
"""Execute program (MS Windows version)"""
|
|
|
|
if not isinstance(args, types.StringTypes):
|
|
args = list2cmdline(args)
|
|
|
|
# Process startup details
|
|
if startupinfo is None:
|
|
startupinfo = STARTUPINFO()
|
|
if None not in (p2cread, c2pwrite, errwrite):
|
|
startupinfo.dwFlags |= _subprocess.STARTF_USESTDHANDLES
|
|
startupinfo.hStdInput = p2cread
|
|
startupinfo.hStdOutput = c2pwrite
|
|
startupinfo.hStdError = errwrite
|
|
|
|
if shell:
|
|
startupinfo.dwFlags |= _subprocess.STARTF_USESHOWWINDOW
|
|
startupinfo.wShowWindow = _subprocess.SW_HIDE
|
|
comspec = os.environ.get("COMSPEC", "cmd.exe")
|
|
args = '{} /c "{}"'.format (comspec, args)
|
|
if (_subprocess.GetVersion() >= 0x80000000 or
|
|
os.path.basename(comspec).lower() == "command.com"):
|
|
# Win9x, or using command.com on NT. We need to
|
|
# use the w9xpopen intermediate program. For more
|
|
# information, see KB Q150956
|
|
# (http://web.archive.org/web/20011105084002/http://support.microsoft.com/support/kb/articles/Q150/9/56.asp)
|
|
w9xpopen = self._find_w9xpopen()
|
|
args = '"%s" %s' % (w9xpopen, args)
|
|
# Not passing CREATE_NEW_CONSOLE has been known to
|
|
# cause random failures on win9x. Specifically a
|
|
# dialog: "Your program accessed mem currently in
|
|
# use at xxx" and a hopeful warning about the
|
|
# stability of your system. Cost is Ctrl+C wont
|
|
# kill children.
|
|
creationflags |= _subprocess.CREATE_NEW_CONSOLE
|
|
|
|
def _close_in_parent(fd):
|
|
fd.Close()
|
|
to_close.remove(fd)
|
|
|
|
# Start the process
|
|
try:
|
|
hp, ht, pid, tid = _subprocess.CreateProcess(executable, args,
|
|
# no special security
|
|
None, None,
|
|
int(not close_fds),
|
|
creationflags,
|
|
env,
|
|
cwd,
|
|
startupinfo)
|
|
except pywintypes.error, e:
|
|
# Translate pywintypes.error to WindowsError, which is
|
|
# a subclass of OSError. FIXME: We should really
|
|
# translate errno using _sys_errlist (or similar), but
|
|
# how can this be done from Python?
|
|
raise WindowsError(*e.args)
|
|
finally:
|
|
# Child is launched. Close the parent's copy of those pipe
|
|
# handles that only the child should have open. You need
|
|
# to make sure that no handles to the write end of the
|
|
# output pipe are maintained in this process or else the
|
|
# pipe will not close when the child process exits and the
|
|
# ReadFile will hang.
|
|
if p2cread is not None:
|
|
_close_in_parent(p2cread)
|
|
if c2pwrite is not None:
|
|
_close_in_parent(c2pwrite)
|
|
if errwrite is not None:
|
|
_close_in_parent(errwrite)
|
|
|
|
# Retain the process handle, but close the thread handle
|
|
self._child_created = True
|
|
self._handle = hp
|
|
self.pid = pid
|
|
ht.Close()
|
|
|
|
def _internal_poll(self, _deadstate=None,
|
|
_WaitForSingleObject=_subprocess.WaitForSingleObject,
|
|
_WAIT_OBJECT_0=_subprocess.WAIT_OBJECT_0,
|
|
_GetExitCodeProcess=_subprocess.GetExitCodeProcess):
|
|
"""Check if child process has terminated. Returns returncode
|
|
attribute.
|
|
|
|
This method is called by __del__, so it can only refer to objects
|
|
in its local scope.
|
|
|
|
"""
|
|
if self.returncode is None:
|
|
if _WaitForSingleObject(self._handle, 0) == _WAIT_OBJECT_0:
|
|
self.returncode = _GetExitCodeProcess(self._handle)
|
|
return self.returncode
|
|
|
|
|
|
def wait(self):
|
|
"""Wait for child process to terminate. Returns returncode
|
|
attribute."""
|
|
if self.returncode is None:
|
|
_subprocess.WaitForSingleObject(self._handle,
|
|
_subprocess.INFINITE)
|
|
self.returncode = _subprocess.GetExitCodeProcess(self._handle)
|
|
return self.returncode
|
|
|
|
|
|
def _readerthread(self, fh, buffer):
|
|
buffer.append(fh.read())
|
|
|
|
|
|
def _communicate(self, input):
|
|
stdout = None # Return
|
|
stderr = None # Return
|
|
|
|
if self.stdout:
|
|
stdout = []
|
|
stdout_thread = threading.Thread(target=self._readerthread,
|
|
args=(self.stdout, stdout))
|
|
stdout_thread.setDaemon(True)
|
|
stdout_thread.start()
|
|
if self.stderr:
|
|
stderr = []
|
|
stderr_thread = threading.Thread(target=self._readerthread,
|
|
args=(self.stderr, stderr))
|
|
stderr_thread.setDaemon(True)
|
|
stderr_thread.start()
|
|
|
|
if self.stdin:
|
|
if input is not None:
|
|
try:
|
|
self.stdin.write(input)
|
|
except IOError as e:
|
|
if e.errno == errno.EPIPE:
|
|
# communicate() should ignore broken pipe error
|
|
pass
|
|
elif e.errno == errno.EINVAL:
|
|
# bpo-19612, bpo-30418: On Windows, stdin.write()
|
|
# fails with EINVAL if the child process exited or
|
|
# if the child process is still running but closed
|
|
# the pipe.
|
|
pass
|
|
else:
|
|
raise
|
|
self.stdin.close()
|
|
|
|
if self.stdout:
|
|
stdout_thread.join()
|
|
if self.stderr:
|
|
stderr_thread.join()
|
|
|
|
# All data exchanged. Translate lists into strings.
|
|
if stdout is not None:
|
|
stdout = stdout[0]
|
|
if stderr is not None:
|
|
stderr = stderr[0]
|
|
|
|
# Translate newlines, if requested. We cannot let the file
|
|
# object do the translation: It is based on stdio, which is
|
|
# impossible to combine with select (unless forcing no
|
|
# buffering).
|
|
if self.universal_newlines and hasattr(file, 'newlines'):
|
|
if stdout:
|
|
stdout = self._translate_newlines(stdout)
|
|
if stderr:
|
|
stderr = self._translate_newlines(stderr)
|
|
|
|
self.wait()
|
|
return (stdout, stderr)
|
|
|
|
def send_signal(self, sig):
|
|
"""Send a signal to the process
|
|
"""
|
|
if sig == signal.SIGTERM:
|
|
self.terminate()
|
|
elif sig == signal.CTRL_C_EVENT:
|
|
os.kill(self.pid, signal.CTRL_C_EVENT)
|
|
elif sig == signal.CTRL_BREAK_EVENT:
|
|
os.kill(self.pid, signal.CTRL_BREAK_EVENT)
|
|
else:
|
|
raise ValueError("Unsupported signal: {}".format(sig))
|
|
|
|
def terminate(self):
|
|
"""Terminates the process
|
|
"""
|
|
try:
|
|
_subprocess.TerminateProcess(self._handle, 1)
|
|
except OSError as e:
|
|
# ERROR_ACCESS_DENIED (winerror 5) is received when the
|
|
# process already died.
|
|
if e.winerror != 5:
|
|
raise
|
|
rc = _subprocess.GetExitCodeProcess(self._handle)
|
|
if rc == _subprocess.STILL_ACTIVE:
|
|
raise
|
|
self.returncode = rc
|
|
|
|
kill = terminate
|
|
|
|
else:
|
|
#
|
|
# POSIX methods
|
|
#
|
|
def _get_handles(self, stdin, stdout, stderr):
|
|
"""Construct and return tuple with IO objects:
|
|
p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite
|
|
"""
|
|
to_close = set()
|
|
p2cread, p2cwrite = None, None
|
|
c2pread, c2pwrite = None, None
|
|
errread, errwrite = None, None
|
|
|
|
if stdin is None:
|
|
pass
|
|
elif stdin == PIPE:
|
|
p2cread, p2cwrite = self.pipe_cloexec()
|
|
to_close.update((p2cread, p2cwrite))
|
|
elif isinstance(stdin, (int, long)):
|
|
p2cread = stdin
|
|
else:
|
|
# Assuming file-like object
|
|
p2cread = stdin.fileno()
|
|
|
|
if stdout is None:
|
|
pass
|
|
elif stdout == PIPE:
|
|
c2pread, c2pwrite = self.pipe_cloexec()
|
|
to_close.update((c2pread, c2pwrite))
|
|
elif isinstance(stdout, (int, long)):
|
|
c2pwrite = stdout
|
|
else:
|
|
# Assuming file-like object
|
|
c2pwrite = stdout.fileno()
|
|
|
|
if stderr is None:
|
|
pass
|
|
elif stderr == PIPE:
|
|
errread, errwrite = self.pipe_cloexec()
|
|
to_close.update((errread, errwrite))
|
|
elif stderr == STDOUT:
|
|
if c2pwrite is not None:
|
|
errwrite = c2pwrite
|
|
else: # child's stdout is not set, use parent's stdout
|
|
errwrite = sys.__stdout__.fileno()
|
|
elif isinstance(stderr, (int, long)):
|
|
errwrite = stderr
|
|
else:
|
|
# Assuming file-like object
|
|
errwrite = stderr.fileno()
|
|
|
|
return (p2cread, p2cwrite,
|
|
c2pread, c2pwrite,
|
|
errread, errwrite), to_close
|
|
|
|
|
|
def _set_cloexec_flag(self, fd, cloexec=True):
|
|
try:
|
|
cloexec_flag = fcntl.FD_CLOEXEC
|
|
except AttributeError:
|
|
cloexec_flag = 1
|
|
|
|
old = fcntl.fcntl(fd, fcntl.F_GETFD)
|
|
if cloexec:
|
|
fcntl.fcntl(fd, fcntl.F_SETFD, old | cloexec_flag)
|
|
else:
|
|
fcntl.fcntl(fd, fcntl.F_SETFD, old & ~cloexec_flag)
|
|
|
|
|
|
def pipe_cloexec(self):
|
|
"""Create a pipe with FDs set CLOEXEC."""
|
|
# Pipes' FDs are set CLOEXEC by default because we don't want them
|
|
# to be inherited by other subprocesses: the CLOEXEC flag is removed
|
|
# from the child's FDs by _dup2(), between fork() and exec().
|
|
# This is not atomic: we would need the pipe2() syscall for that.
|
|
r, w = os.pipe()
|
|
self._set_cloexec_flag(r)
|
|
self._set_cloexec_flag(w)
|
|
return r, w
|
|
|
|
|
|
def _close_fds(self, but):
|
|
if hasattr(os, 'closerange'):
|
|
os.closerange(3, but)
|
|
os.closerange(but + 1, MAXFD)
|
|
else:
|
|
for i in xrange(3, MAXFD):
|
|
if i == but:
|
|
continue
|
|
try:
|
|
os.close(i)
|
|
except:
|
|
pass
|
|
|
|
|
|
# Used as a bandaid workaround for https://bugs.python.org/issue27448
|
|
# to prevent multiple simultaneous subprocess launches from interfering
|
|
# with one another and leaving gc disabled.
|
|
if threading:
|
|
_disabling_gc_lock = threading.Lock()
|
|
else:
|
|
class _noop_context_manager(object):
|
|
# A dummy context manager that does nothing for the rare
|
|
# user of a --without-threads build.
|
|
def __enter__(self): pass
|
|
def __exit__(self, *args): pass
|
|
|
|
_disabling_gc_lock = _noop_context_manager()
|
|
|
|
|
|
def _execute_child(self, args, executable, preexec_fn, close_fds,
|
|
cwd, env, universal_newlines,
|
|
startupinfo, creationflags, shell, to_close,
|
|
p2cread, p2cwrite,
|
|
c2pread, c2pwrite,
|
|
errread, errwrite):
|
|
"""Execute program (POSIX version)"""
|
|
|
|
if isinstance(args, types.StringTypes):
|
|
args = [args]
|
|
else:
|
|
args = list(args)
|
|
|
|
if shell:
|
|
args = ["/bin/sh", "-c"] + args
|
|
if executable:
|
|
args[0] = executable
|
|
|
|
if executable is None:
|
|
executable = args[0]
|
|
|
|
def _close_in_parent(fd):
|
|
os.close(fd)
|
|
to_close.remove(fd)
|
|
|
|
# For transferring possible exec failure from child to parent
|
|
# The first char specifies the exception type: 0 means
|
|
# OSError, 1 means some other error.
|
|
errpipe_read, errpipe_write = self.pipe_cloexec()
|
|
try:
|
|
try:
|
|
with self._disabling_gc_lock:
|
|
gc_was_enabled = gc.isenabled()
|
|
# Disable gc to avoid bug where gc -> file_dealloc ->
|
|
# write to stderr -> hang.
|
|
# https://bugs.python.org/issue1336
|
|
gc.disable()
|
|
try:
|
|
self.pid = os.fork()
|
|
except:
|
|
if gc_was_enabled:
|
|
gc.enable()
|
|
raise
|
|
self._child_created = True
|
|
if self.pid == 0:
|
|
# Child
|
|
try:
|
|
# Close parent's pipe ends
|
|
if p2cwrite is not None:
|
|
os.close(p2cwrite)
|
|
if c2pread is not None:
|
|
os.close(c2pread)
|
|
if errread is not None:
|
|
os.close(errread)
|
|
os.close(errpipe_read)
|
|
|
|
# When duping fds, if there arises a situation
|
|
# where one of the fds is either 0, 1 or 2, it
|
|
# is possible that it is overwritten (#12607).
|
|
if c2pwrite == 0:
|
|
c2pwrite = os.dup(c2pwrite)
|
|
if errwrite == 0 or errwrite == 1:
|
|
errwrite = os.dup(errwrite)
|
|
|
|
# Dup fds for child
|
|
def _dup2(a, b):
|
|
# dup2() removes the CLOEXEC flag but
|
|
# we must do it ourselves if dup2()
|
|
# would be a no-op (issue #10806).
|
|
if a == b:
|
|
self._set_cloexec_flag(a, False)
|
|
elif a is not None:
|
|
os.dup2(a, b)
|
|
_dup2(p2cread, 0)
|
|
_dup2(c2pwrite, 1)
|
|
_dup2(errwrite, 2)
|
|
|
|
# Close pipe fds. Make sure we don't close the
|
|
# same fd more than once, or standard fds.
|
|
closed = { None }
|
|
for fd in [p2cread, c2pwrite, errwrite]:
|
|
if fd not in closed and fd > 2:
|
|
os.close(fd)
|
|
closed.add(fd)
|
|
|
|
if cwd is not None:
|
|
os.chdir(cwd)
|
|
|
|
if preexec_fn:
|
|
preexec_fn()
|
|
|
|
# Close all other fds, if asked for - after
|
|
# preexec_fn(), which may open FDs.
|
|
if close_fds:
|
|
self._close_fds(but=errpipe_write)
|
|
|
|
if env is None:
|
|
os.execvp(executable, args)
|
|
else:
|
|
os.execvpe(executable, args, env)
|
|
|
|
except:
|
|
exc_type, exc_value, tb = sys.exc_info()
|
|
# Save the traceback and attach it to the exception object
|
|
exc_lines = traceback.format_exception(exc_type,
|
|
exc_value,
|
|
tb)
|
|
exc_value.child_traceback = ''.join(exc_lines)
|
|
os.write(errpipe_write, pickle.dumps(exc_value))
|
|
|
|
finally:
|
|
# This exitcode won't be reported to applications, so it
|
|
# really doesn't matter what we return.
|
|
os._exit(255)
|
|
|
|
# Parent
|
|
if gc_was_enabled:
|
|
gc.enable()
|
|
finally:
|
|
# be sure the FD is closed no matter what
|
|
os.close(errpipe_write)
|
|
|
|
# Wait for exec to fail or succeed; possibly raising exception
|
|
data = _eintr_retry_call(os.read, errpipe_read, 1048576)
|
|
pickle_bits = []
|
|
while data:
|
|
pickle_bits.append(data)
|
|
data = _eintr_retry_call(os.read, errpipe_read, 1048576)
|
|
data = "".join(pickle_bits)
|
|
finally:
|
|
if p2cread is not None and p2cwrite is not None:
|
|
_close_in_parent(p2cread)
|
|
if c2pwrite is not None and c2pread is not None:
|
|
_close_in_parent(c2pwrite)
|
|
if errwrite is not None and errread is not None:
|
|
_close_in_parent(errwrite)
|
|
|
|
# be sure the FD is closed no matter what
|
|
os.close(errpipe_read)
|
|
|
|
if data != "":
|
|
try:
|
|
_eintr_retry_call(os.waitpid, self.pid, 0)
|
|
except OSError as e:
|
|
if e.errno != errno.ECHILD:
|
|
raise
|
|
child_exception = pickle.loads(data)
|
|
raise child_exception
|
|
|
|
|
|
def _handle_exitstatus(self, sts, _WIFSIGNALED=os.WIFSIGNALED,
|
|
_WTERMSIG=os.WTERMSIG, _WIFEXITED=os.WIFEXITED,
|
|
_WEXITSTATUS=os.WEXITSTATUS, _WIFSTOPPED=os.WIFSTOPPED,
|
|
_WSTOPSIG=os.WSTOPSIG):
|
|
# This method is called (indirectly) by __del__, so it cannot
|
|
# refer to anything outside of its local scope.
|
|
if _WIFSIGNALED(sts):
|
|
self.returncode = -_WTERMSIG(sts)
|
|
elif _WIFEXITED(sts):
|
|
self.returncode = _WEXITSTATUS(sts)
|
|
elif _WIFSTOPPED(sts):
|
|
self.returncode = -_WSTOPSIG(sts)
|
|
else:
|
|
# Should never happen
|
|
raise RuntimeError("Unknown child exit status!")
|
|
|
|
|
|
def _internal_poll(self, _deadstate=None, _waitpid=os.waitpid,
|
|
_WNOHANG=os.WNOHANG, _os_error=os.error, _ECHILD=errno.ECHILD):
|
|
"""Check if child process has terminated. Returns returncode
|
|
attribute.
|
|
|
|
This method is called by __del__, so it cannot reference anything
|
|
outside of the local scope (nor can any methods it calls).
|
|
|
|
"""
|
|
if self.returncode is None:
|
|
try:
|
|
pid, sts = _waitpid(self.pid, _WNOHANG)
|
|
if pid == self.pid:
|
|
self._handle_exitstatus(sts)
|
|
except _os_error as e:
|
|
if _deadstate is not None:
|
|
self.returncode = _deadstate
|
|
if e.errno == _ECHILD:
|
|
# This happens if SIGCLD is set to be ignored or
|
|
# waiting for child processes has otherwise been
|
|
# disabled for our process. This child is dead, we
|
|
# can't get the status.
|
|
# http://bugs.python.org/issue15756
|
|
self.returncode = 0
|
|
return self.returncode
|
|
|
|
|
|
def wait(self):
|
|
"""Wait for child process to terminate. Returns returncode
|
|
attribute."""
|
|
while self.returncode is None:
|
|
try:
|
|
pid, sts = _eintr_retry_call(os.waitpid, self.pid, 0)
|
|
except OSError as e:
|
|
if e.errno != errno.ECHILD:
|
|
raise
|
|
# This happens if SIGCLD is set to be ignored or waiting
|
|
# for child processes has otherwise been disabled for our
|
|
# process. This child is dead, we can't get the status.
|
|
pid = self.pid
|
|
sts = 0
|
|
# Check the pid and loop as waitpid has been known to return
|
|
# 0 even without WNOHANG in odd situations. issue14396.
|
|
if pid == self.pid:
|
|
self._handle_exitstatus(sts)
|
|
return self.returncode
|
|
|
|
|
|
def _communicate(self, input):
|
|
if self.stdin:
|
|
# Flush stdio buffer. This might block, if the user has
|
|
# been writing to .stdin in an uncontrolled fashion.
|
|
self.stdin.flush()
|
|
if not input:
|
|
self.stdin.close()
|
|
|
|
if _has_poll:
|
|
stdout, stderr = self._communicate_with_poll(input)
|
|
else:
|
|
stdout, stderr = self._communicate_with_select(input)
|
|
|
|
# All data exchanged. Translate lists into strings.
|
|
if stdout is not None:
|
|
stdout = ''.join(stdout)
|
|
if stderr is not None:
|
|
stderr = ''.join(stderr)
|
|
|
|
# Translate newlines, if requested. We cannot let the file
|
|
# object do the translation: It is based on stdio, which is
|
|
# impossible to combine with select (unless forcing no
|
|
# buffering).
|
|
if self.universal_newlines and hasattr(file, 'newlines'):
|
|
if stdout:
|
|
stdout = self._translate_newlines(stdout)
|
|
if stderr:
|
|
stderr = self._translate_newlines(stderr)
|
|
|
|
self.wait()
|
|
return (stdout, stderr)
|
|
|
|
|
|
def _communicate_with_poll(self, input):
|
|
stdout = None # Return
|
|
stderr = None # Return
|
|
fd2file = {}
|
|
fd2output = {}
|
|
|
|
poller = select.poll()
|
|
def register_and_append(file_obj, eventmask):
|
|
poller.register(file_obj.fileno(), eventmask)
|
|
fd2file[file_obj.fileno()] = file_obj
|
|
|
|
def close_unregister_and_remove(fd):
|
|
poller.unregister(fd)
|
|
fd2file[fd].close()
|
|
fd2file.pop(fd)
|
|
|
|
if self.stdin and input:
|
|
register_and_append(self.stdin, select.POLLOUT)
|
|
|
|
select_POLLIN_POLLPRI = select.POLLIN | select.POLLPRI
|
|
if self.stdout:
|
|
register_and_append(self.stdout, select_POLLIN_POLLPRI)
|
|
fd2output[self.stdout.fileno()] = stdout = []
|
|
if self.stderr:
|
|
register_and_append(self.stderr, select_POLLIN_POLLPRI)
|
|
fd2output[self.stderr.fileno()] = stderr = []
|
|
|
|
input_offset = 0
|
|
while fd2file:
|
|
try:
|
|
ready = poller.poll()
|
|
except select.error, e:
|
|
if e.args[0] == errno.EINTR:
|
|
continue
|
|
raise
|
|
|
|
for fd, mode in ready:
|
|
if mode & select.POLLOUT:
|
|
chunk = input[input_offset : input_offset + _PIPE_BUF]
|
|
try:
|
|
input_offset += os.write(fd, chunk)
|
|
except OSError as e:
|
|
if e.errno == errno.EPIPE:
|
|
close_unregister_and_remove(fd)
|
|
else:
|
|
raise
|
|
else:
|
|
if input_offset >= len(input):
|
|
close_unregister_and_remove(fd)
|
|
elif mode & select_POLLIN_POLLPRI:
|
|
data = os.read(fd, 4096)
|
|
if not data:
|
|
close_unregister_and_remove(fd)
|
|
fd2output[fd].append(data)
|
|
else:
|
|
# Ignore hang up or errors.
|
|
close_unregister_and_remove(fd)
|
|
|
|
return (stdout, stderr)
|
|
|
|
|
|
def _communicate_with_select(self, input):
|
|
read_set = []
|
|
write_set = []
|
|
stdout = None # Return
|
|
stderr = None # Return
|
|
|
|
if self.stdin and input:
|
|
write_set.append(self.stdin)
|
|
if self.stdout:
|
|
read_set.append(self.stdout)
|
|
stdout = []
|
|
if self.stderr:
|
|
read_set.append(self.stderr)
|
|
stderr = []
|
|
|
|
input_offset = 0
|
|
while read_set or write_set:
|
|
try:
|
|
rlist, wlist, xlist = select.select(read_set, write_set, [])
|
|
except select.error, e:
|
|
if e.args[0] == errno.EINTR:
|
|
continue
|
|
raise
|
|
|
|
if self.stdin in wlist:
|
|
chunk = input[input_offset : input_offset + _PIPE_BUF]
|
|
try:
|
|
bytes_written = os.write(self.stdin.fileno(), chunk)
|
|
except OSError as e:
|
|
if e.errno == errno.EPIPE:
|
|
self.stdin.close()
|
|
write_set.remove(self.stdin)
|
|
else:
|
|
raise
|
|
else:
|
|
input_offset += bytes_written
|
|
if input_offset >= len(input):
|
|
self.stdin.close()
|
|
write_set.remove(self.stdin)
|
|
|
|
if self.stdout in rlist:
|
|
data = os.read(self.stdout.fileno(), 1024)
|
|
if data == "":
|
|
self.stdout.close()
|
|
read_set.remove(self.stdout)
|
|
stdout.append(data)
|
|
|
|
if self.stderr in rlist:
|
|
data = os.read(self.stderr.fileno(), 1024)
|
|
if data == "":
|
|
self.stderr.close()
|
|
read_set.remove(self.stderr)
|
|
stderr.append(data)
|
|
|
|
return (stdout, stderr)
|
|
|
|
|
|
def send_signal(self, sig):
|
|
"""Send a signal to the process
|
|
"""
|
|
os.kill(self.pid, sig)
|
|
|
|
def terminate(self):
|
|
"""Terminate the process with SIGTERM
|
|
"""
|
|
self.send_signal(signal.SIGTERM)
|
|
|
|
def kill(self):
|
|
"""Kill the process with SIGKILL
|
|
"""
|
|
self.send_signal(signal.SIGKILL)
|
|
|
|
|
|
def _demo_posix():
|
|
#
|
|
# Example 1: Simple redirection: Get process list
|
|
#
|
|
plist = Popen(["ps"], stdout=PIPE).communicate()[0]
|
|
print "Process list:"
|
|
print plist
|
|
|
|
#
|
|
# Example 2: Change uid before executing child
|
|
#
|
|
if os.getuid() == 0:
|
|
p = Popen(["id"], preexec_fn=lambda: os.setuid(100))
|
|
p.wait()
|
|
|
|
#
|
|
# Example 3: Connecting several subprocesses
|
|
#
|
|
print "Looking for 'hda'..."
|
|
p1 = Popen(["dmesg"], stdout=PIPE)
|
|
p2 = Popen(["grep", "hda"], stdin=p1.stdout, stdout=PIPE)
|
|
print repr(p2.communicate()[0])
|
|
|
|
#
|
|
# Example 4: Catch execution error
|
|
#
|
|
print
|
|
print "Trying a weird file..."
|
|
try:
|
|
print Popen(["/this/path/does/not/exist"]).communicate()
|
|
except OSError, e:
|
|
if e.errno == errno.ENOENT:
|
|
print "The file didn't exist. I thought so..."
|
|
print "Child traceback:"
|
|
print e.child_traceback
|
|
else:
|
|
print "Error", e.errno
|
|
else:
|
|
print >>sys.stderr, "Gosh. No error."
|
|
|
|
|
|
def _demo_windows():
|
|
#
|
|
# Example 1: Connecting several subprocesses
|
|
#
|
|
print "Looking for 'PROMPT' in set output..."
|
|
p1 = Popen("set", stdout=PIPE, shell=True)
|
|
p2 = Popen('find "PROMPT"', stdin=p1.stdout, stdout=PIPE)
|
|
print repr(p2.communicate()[0])
|
|
|
|
#
|
|
# Example 2: Simple execution of program
|
|
#
|
|
print "Executing calc..."
|
|
p = Popen("calc")
|
|
p.wait()
|
|
|
|
|
|
if __name__ == "__main__":
|
|
if mswindows:
|
|
_demo_windows()
|
|
else:
|
|
_demo_posix()
|