mirror of https://github.com/evilhero/mylar
1545 lines
55 KiB
Python
1545 lines
55 KiB
Python
|
# subprocess - Subprocesses with accessible I/O streams
|
||
|
#
|
||
|
# For more information about this module, see PEP 324.
|
||
|
#
|
||
|
# This module should remain compatible with Python 2.2, see PEP 291.
|
||
|
#
|
||
|
# Copyright (c) 2003-2005 by Peter Astrand <astrand@lysator.liu.se>
|
||
|
#
|
||
|
# Licensed to PSF under a Contributor Agreement.
|
||
|
# See http://www.python.org/2.4/license for licensing details.
|
||
|
|
||
|
r"""subprocess - Subprocesses with accessible I/O streams
|
||
|
|
||
|
This module allows you to spawn processes, connect to their
|
||
|
input/output/error pipes, and obtain their return codes. This module
|
||
|
intends to replace several other, older modules and functions, like:
|
||
|
|
||
|
os.system
|
||
|
os.spawn*
|
||
|
os.popen*
|
||
|
popen2.*
|
||
|
commands.*
|
||
|
|
||
|
Information about how the subprocess module can be used to replace these
|
||
|
modules and functions can be found below.
|
||
|
|
||
|
|
||
|
|
||
|
Using the subprocess module
|
||
|
===========================
|
||
|
This module defines one class called Popen:
|
||
|
|
||
|
class Popen(args, bufsize=0, executable=None,
|
||
|
stdin=None, stdout=None, stderr=None,
|
||
|
preexec_fn=None, close_fds=False, shell=False,
|
||
|
cwd=None, env=None, universal_newlines=False,
|
||
|
startupinfo=None, creationflags=0):
|
||
|
|
||
|
|
||
|
Arguments are:
|
||
|
|
||
|
args should be a string, or a sequence of program arguments. The
|
||
|
program to execute is normally the first item in the args sequence or
|
||
|
string, but can be explicitly set by using the executable argument.
|
||
|
|
||
|
On UNIX, with shell=False (default): In this case, the Popen class
|
||
|
uses os.execvp() to execute the child program. args should normally
|
||
|
be a sequence. A string will be treated as a sequence with the string
|
||
|
as the only item (the program to execute).
|
||
|
|
||
|
On UNIX, with shell=True: If args is a string, it specifies the
|
||
|
command string to execute through the shell. If args is a sequence,
|
||
|
the first item specifies the command string, and any additional items
|
||
|
will be treated as additional shell arguments.
|
||
|
|
||
|
On Windows: the Popen class uses CreateProcess() to execute the child
|
||
|
program, which operates on strings. If args is a sequence, it will be
|
||
|
converted to a string using the list2cmdline method. Please note that
|
||
|
not all MS Windows applications interpret the command line the same
|
||
|
way: The list2cmdline is designed for applications using the same
|
||
|
rules as the MS C runtime.
|
||
|
|
||
|
bufsize, if given, has the same meaning as the corresponding argument
|
||
|
to the built-in open() function: 0 means unbuffered, 1 means line
|
||
|
buffered, any other positive value means use a buffer of
|
||
|
(approximately) that size. A negative bufsize means to use the system
|
||
|
default, which usually means fully buffered. The default value for
|
||
|
bufsize is 0 (unbuffered).
|
||
|
|
||
|
stdin, stdout and stderr specify the executed programs' standard
|
||
|
input, standard output and standard error file handles, respectively.
|
||
|
Valid values are PIPE, an existing file descriptor (a positive
|
||
|
integer), an existing file object, and None. PIPE indicates that a
|
||
|
new pipe to the child should be created. With None, no redirection
|
||
|
will occur; the child's file handles will be inherited from the
|
||
|
parent. Additionally, stderr can be STDOUT, which indicates that the
|
||
|
stderr data from the applications should be captured into the same
|
||
|
file handle as for stdout.
|
||
|
|
||
|
If preexec_fn is set to a callable object, this object will be called
|
||
|
in the child process just before the child is executed.
|
||
|
|
||
|
If close_fds is true, all file descriptors except 0, 1 and 2 will be
|
||
|
closed before the child process is executed.
|
||
|
|
||
|
if shell is true, the specified command will be executed through the
|
||
|
shell.
|
||
|
|
||
|
If cwd is not None, the current directory will be changed to cwd
|
||
|
before the child is executed.
|
||
|
|
||
|
If env is not None, it defines the environment variables for the new
|
||
|
process.
|
||
|
|
||
|
If universal_newlines is true, the file objects stdout and stderr are
|
||
|
opened as a text files, but lines may be terminated by any of '\n',
|
||
|
the Unix end-of-line convention, '\r', the Macintosh convention or
|
||
|
'\r\n', the Windows convention. All of these external representations
|
||
|
are seen as '\n' by the Python program. Note: This feature is only
|
||
|
available if Python is built with universal newline support (the
|
||
|
default). Also, the newlines attribute of the file objects stdout,
|
||
|
stdin and stderr are not updated by the communicate() method.
|
||
|
|
||
|
The startupinfo and creationflags, if given, will be passed to the
|
||
|
underlying CreateProcess() function. They can specify things such as
|
||
|
appearance of the main window and priority for the new process.
|
||
|
(Windows only)
|
||
|
|
||
|
|
||
|
This module also defines some shortcut functions:
|
||
|
|
||
|
call(*popenargs, **kwargs):
|
||
|
Run command with arguments. Wait for command to complete, then
|
||
|
return the returncode attribute.
|
||
|
|
||
|
The arguments are the same as for the Popen constructor. Example:
|
||
|
|
||
|
retcode = call(["ls", "-l"])
|
||
|
|
||
|
check_call(*popenargs, **kwargs):
|
||
|
Run command with arguments. Wait for command to complete. If the
|
||
|
exit code was zero then return, otherwise raise
|
||
|
CalledProcessError. The CalledProcessError object will have the
|
||
|
return code in the returncode attribute.
|
||
|
|
||
|
The arguments are the same as for the Popen constructor. Example:
|
||
|
|
||
|
check_call(["ls", "-l"])
|
||
|
|
||
|
check_output(*popenargs, **kwargs):
|
||
|
Run command with arguments and return its output as a byte string.
|
||
|
|
||
|
If the exit code was non-zero it raises a CalledProcessError. The
|
||
|
CalledProcessError object will have the return code in the returncode
|
||
|
attribute and output in the output attribute.
|
||
|
|
||
|
The arguments are the same as for the Popen constructor. Example:
|
||
|
|
||
|
output = check_output(["ls", "-l", "/dev/null"])
|
||
|
|
||
|
|
||
|
Exceptions
|
||
|
----------
|
||
|
Exceptions raised in the child process, before the new program has
|
||
|
started to execute, will be re-raised in the parent. Additionally,
|
||
|
the exception object will have one extra attribute called
|
||
|
'child_traceback', which is a string containing traceback information
|
||
|
from the childs point of view.
|
||
|
|
||
|
The most common exception raised is OSError. This occurs, for
|
||
|
example, when trying to execute a non-existent file. Applications
|
||
|
should prepare for OSErrors.
|
||
|
|
||
|
A ValueError will be raised if Popen is called with invalid arguments.
|
||
|
|
||
|
check_call() and check_output() will raise CalledProcessError, if the
|
||
|
called process returns a non-zero return code.
|
||
|
|
||
|
|
||
|
Security
|
||
|
--------
|
||
|
Unlike some other popen functions, this implementation will never call
|
||
|
/bin/sh implicitly. This means that all characters, including shell
|
||
|
metacharacters, can safely be passed to child processes.
|
||
|
|
||
|
|
||
|
Popen objects
|
||
|
=============
|
||
|
Instances of the Popen class have the following methods:
|
||
|
|
||
|
poll()
|
||
|
Check if child process has terminated. Returns returncode
|
||
|
attribute.
|
||
|
|
||
|
wait()
|
||
|
Wait for child process to terminate. Returns returncode attribute.
|
||
|
|
||
|
communicate(input=None)
|
||
|
Interact with process: Send data to stdin. Read data from stdout
|
||
|
and stderr, until end-of-file is reached. Wait for process to
|
||
|
terminate. The optional input argument should be a string to be
|
||
|
sent to the child process, or None, if no data should be sent to
|
||
|
the child.
|
||
|
|
||
|
communicate() returns a tuple (stdout, stderr).
|
||
|
|
||
|
Note: The data read is buffered in memory, so do not use this
|
||
|
method if the data size is large or unlimited.
|
||
|
|
||
|
The following attributes are also available:
|
||
|
|
||
|
stdin
|
||
|
If the stdin argument is PIPE, this attribute is a file object
|
||
|
that provides input to the child process. Otherwise, it is None.
|
||
|
|
||
|
stdout
|
||
|
If the stdout argument is PIPE, this attribute is a file object
|
||
|
that provides output from the child process. Otherwise, it is
|
||
|
None.
|
||
|
|
||
|
stderr
|
||
|
If the stderr argument is PIPE, this attribute is file object that
|
||
|
provides error output from the child process. Otherwise, it is
|
||
|
None.
|
||
|
|
||
|
pid
|
||
|
The process ID of the child process.
|
||
|
|
||
|
returncode
|
||
|
The child return code. A None value indicates that the process
|
||
|
hasn't terminated yet. A negative value -N indicates that the
|
||
|
child was terminated by signal N (UNIX only).
|
||
|
|
||
|
|
||
|
Replacing older functions with the subprocess module
|
||
|
====================================================
|
||
|
In this section, "a ==> b" means that b can be used as a replacement
|
||
|
for a.
|
||
|
|
||
|
Note: All functions in this section fail (more or less) silently if
|
||
|
the executed program cannot be found; this module raises an OSError
|
||
|
exception.
|
||
|
|
||
|
In the following examples, we assume that the subprocess module is
|
||
|
imported with "from subprocess import *".
|
||
|
|
||
|
|
||
|
Replacing /bin/sh shell backquote
|
||
|
---------------------------------
|
||
|
output=`mycmd myarg`
|
||
|
==>
|
||
|
output = Popen(["mycmd", "myarg"], stdout=PIPE).communicate()[0]
|
||
|
|
||
|
|
||
|
Replacing shell pipe line
|
||
|
-------------------------
|
||
|
output=`dmesg | grep hda`
|
||
|
==>
|
||
|
p1 = Popen(["dmesg"], stdout=PIPE)
|
||
|
p2 = Popen(["grep", "hda"], stdin=p1.stdout, stdout=PIPE)
|
||
|
output = p2.communicate()[0]
|
||
|
|
||
|
|
||
|
Replacing os.system()
|
||
|
---------------------
|
||
|
sts = os.system("mycmd" + " myarg")
|
||
|
==>
|
||
|
p = Popen("mycmd" + " myarg", shell=True)
|
||
|
pid, sts = os.waitpid(p.pid, 0)
|
||
|
|
||
|
Note:
|
||
|
|
||
|
* Calling the program through the shell is usually not required.
|
||
|
|
||
|
* It's easier to look at the returncode attribute than the
|
||
|
exitstatus.
|
||
|
|
||
|
A more real-world example would look like this:
|
||
|
|
||
|
try:
|
||
|
retcode = call("mycmd" + " myarg", shell=True)
|
||
|
if retcode < 0:
|
||
|
print >>sys.stderr, "Child was terminated by signal", -retcode
|
||
|
else:
|
||
|
print >>sys.stderr, "Child returned", retcode
|
||
|
except OSError, e:
|
||
|
print >>sys.stderr, "Execution failed:", e
|
||
|
|
||
|
|
||
|
Replacing os.spawn*
|
||
|
-------------------
|
||
|
P_NOWAIT example:
|
||
|
|
||
|
pid = os.spawnlp(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg")
|
||
|
==>
|
||
|
pid = Popen(["/bin/mycmd", "myarg"]).pid
|
||
|
|
||
|
|
||
|
P_WAIT example:
|
||
|
|
||
|
retcode = os.spawnlp(os.P_WAIT, "/bin/mycmd", "mycmd", "myarg")
|
||
|
==>
|
||
|
retcode = call(["/bin/mycmd", "myarg"])
|
||
|
|
||
|
|
||
|
Vector example:
|
||
|
|
||
|
os.spawnvp(os.P_NOWAIT, path, args)
|
||
|
==>
|
||
|
Popen([path] + args[1:])
|
||
|
|
||
|
|
||
|
Environment example:
|
||
|
|
||
|
os.spawnlpe(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg", env)
|
||
|
==>
|
||
|
Popen(["/bin/mycmd", "myarg"], env={"PATH": "/usr/bin"})
|
||
|
|
||
|
|
||
|
Replacing os.popen*
|
||
|
-------------------
|
||
|
pipe = os.popen("cmd", mode='r', bufsize)
|
||
|
==>
|
||
|
pipe = Popen("cmd", shell=True, bufsize=bufsize, stdout=PIPE).stdout
|
||
|
|
||
|
pipe = os.popen("cmd", mode='w', bufsize)
|
||
|
==>
|
||
|
pipe = Popen("cmd", shell=True, bufsize=bufsize, stdin=PIPE).stdin
|
||
|
|
||
|
|
||
|
(child_stdin, child_stdout) = os.popen2("cmd", mode, bufsize)
|
||
|
==>
|
||
|
p = Popen("cmd", shell=True, bufsize=bufsize,
|
||
|
stdin=PIPE, stdout=PIPE, close_fds=True)
|
||
|
(child_stdin, child_stdout) = (p.stdin, p.stdout)
|
||
|
|
||
|
|
||
|
(child_stdin,
|
||
|
child_stdout,
|
||
|
child_stderr) = os.popen3("cmd", mode, bufsize)
|
||
|
==>
|
||
|
p = Popen("cmd", shell=True, bufsize=bufsize,
|
||
|
stdin=PIPE, stdout=PIPE, stderr=PIPE, close_fds=True)
|
||
|
(child_stdin,
|
||
|
child_stdout,
|
||
|
child_stderr) = (p.stdin, p.stdout, p.stderr)
|
||
|
|
||
|
|
||
|
(child_stdin, child_stdout_and_stderr) = os.popen4("cmd", mode,
|
||
|
bufsize)
|
||
|
==>
|
||
|
p = Popen("cmd", shell=True, bufsize=bufsize,
|
||
|
stdin=PIPE, stdout=PIPE, stderr=STDOUT, close_fds=True)
|
||
|
(child_stdin, child_stdout_and_stderr) = (p.stdin, p.stdout)
|
||
|
|
||
|
On Unix, os.popen2, os.popen3 and os.popen4 also accept a sequence as
|
||
|
the command to execute, in which case arguments will be passed
|
||
|
directly to the program without shell intervention. This usage can be
|
||
|
replaced as follows:
|
||
|
|
||
|
(child_stdin, child_stdout) = os.popen2(["/bin/ls", "-l"], mode,
|
||
|
bufsize)
|
||
|
==>
|
||
|
p = Popen(["/bin/ls", "-l"], bufsize=bufsize, stdin=PIPE, stdout=PIPE)
|
||
|
(child_stdin, child_stdout) = (p.stdin, p.stdout)
|
||
|
|
||
|
Return code handling translates as follows:
|
||
|
|
||
|
pipe = os.popen("cmd", 'w')
|
||
|
...
|
||
|
rc = pipe.close()
|
||
|
if rc is not None and rc % 256:
|
||
|
print "There were some errors"
|
||
|
==>
|
||
|
process = Popen("cmd", 'w', shell=True, stdin=PIPE)
|
||
|
...
|
||
|
process.stdin.close()
|
||
|
if process.wait() != 0:
|
||
|
print "There were some errors"
|
||
|
|
||
|
|
||
|
Replacing popen2.*
|
||
|
------------------
|
||
|
(child_stdout, child_stdin) = popen2.popen2("somestring", bufsize, mode)
|
||
|
==>
|
||
|
p = Popen(["somestring"], shell=True, bufsize=bufsize
|
||
|
stdin=PIPE, stdout=PIPE, close_fds=True)
|
||
|
(child_stdout, child_stdin) = (p.stdout, p.stdin)
|
||
|
|
||
|
On Unix, popen2 also accepts a sequence as the command to execute, in
|
||
|
which case arguments will be passed directly to the program without
|
||
|
shell intervention. This usage can be replaced as follows:
|
||
|
|
||
|
(child_stdout, child_stdin) = popen2.popen2(["mycmd", "myarg"], bufsize,
|
||
|
mode)
|
||
|
==>
|
||
|
p = Popen(["mycmd", "myarg"], bufsize=bufsize,
|
||
|
stdin=PIPE, stdout=PIPE, close_fds=True)
|
||
|
(child_stdout, child_stdin) = (p.stdout, p.stdin)
|
||
|
|
||
|
The popen2.Popen3 and popen2.Popen4 basically works as subprocess.Popen,
|
||
|
except that:
|
||
|
|
||
|
* subprocess.Popen raises an exception if the execution fails
|
||
|
* the capturestderr argument is replaced with the stderr argument.
|
||
|
* stdin=PIPE and stdout=PIPE must be specified.
|
||
|
* popen2 closes all filedescriptors by default, but you have to specify
|
||
|
close_fds=True with subprocess.Popen.
|
||
|
"""
|
||
|
|
||
|
import sys
|
||
|
mswindows = (sys.platform == "win32")
|
||
|
|
||
|
import os
|
||
|
import types
|
||
|
import traceback
|
||
|
import gc
|
||
|
import signal
|
||
|
import errno
|
||
|
|
||
|
try:
|
||
|
set
|
||
|
except NameError:
|
||
|
from sets import Set as set
|
||
|
|
||
|
# Exception classes used by this module.
|
||
|
|
||
|
|
||
|
class CalledProcessError(Exception):
|
||
|
|
||
|
"""This exception is raised when a process run by check_call() or
|
||
|
check_output() returns a non-zero exit status.
|
||
|
The exit status will be stored in the returncode attribute;
|
||
|
check_output() will also store the output in the output attribute.
|
||
|
"""
|
||
|
|
||
|
def __init__(self, returncode, cmd, output=None):
|
||
|
self.returncode = returncode
|
||
|
self.cmd = cmd
|
||
|
self.output = output
|
||
|
|
||
|
def __str__(self):
|
||
|
return "Command '%s' returned non-zero exit status %d" % (
|
||
|
self.cmd, self.returncode)
|
||
|
|
||
|
|
||
|
if mswindows:
|
||
|
import threading
|
||
|
import msvcrt
|
||
|
import _subprocess
|
||
|
|
||
|
class STARTUPINFO:
|
||
|
dwFlags = 0
|
||
|
hStdInput = None
|
||
|
hStdOutput = None
|
||
|
hStdError = None
|
||
|
wShowWindow = 0
|
||
|
|
||
|
class pywintypes:
|
||
|
error = IOError
|
||
|
else:
|
||
|
import select
|
||
|
_has_poll = hasattr(select, 'poll')
|
||
|
import fcntl
|
||
|
import pickle
|
||
|
|
||
|
# When select or poll has indicated that the file is writable,
|
||
|
# we can write up to _PIPE_BUF bytes without risk of blocking.
|
||
|
# POSIX defines PIPE_BUF as >= 512.
|
||
|
_PIPE_BUF = getattr(select, 'PIPE_BUF', 512)
|
||
|
|
||
|
|
||
|
__all__ = ["Popen", "PIPE", "STDOUT", "call", "check_call",
|
||
|
"check_output", "CalledProcessError"]
|
||
|
|
||
|
if mswindows:
|
||
|
from _subprocess import CREATE_NEW_CONSOLE, CREATE_NEW_PROCESS_GROUP, \
|
||
|
STD_INPUT_HANDLE, STD_OUTPUT_HANDLE, \
|
||
|
STD_ERROR_HANDLE, SW_HIDE, \
|
||
|
STARTF_USESTDHANDLES, STARTF_USESHOWWINDOW
|
||
|
|
||
|
__all__.extend(["CREATE_NEW_CONSOLE", "CREATE_NEW_PROCESS_GROUP",
|
||
|
"STD_INPUT_HANDLE", "STD_OUTPUT_HANDLE",
|
||
|
"STD_ERROR_HANDLE", "SW_HIDE",
|
||
|
"STARTF_USESTDHANDLES", "STARTF_USESHOWWINDOW"])
|
||
|
try:
|
||
|
MAXFD = os.sysconf("SC_OPEN_MAX")
|
||
|
except:
|
||
|
MAXFD = 256
|
||
|
|
||
|
_active = []
|
||
|
|
||
|
|
||
|
def _cleanup():
|
||
|
for inst in _active[:]:
|
||
|
res = inst._internal_poll(_deadstate=sys.maxint)
|
||
|
if res is not None:
|
||
|
try:
|
||
|
_active.remove(inst)
|
||
|
except ValueError:
|
||
|
# This can happen if two threads create a new Popen instance.
|
||
|
# It's harmless that it was already removed, so ignore.
|
||
|
pass
|
||
|
|
||
|
PIPE = -1
|
||
|
STDOUT = -2
|
||
|
|
||
|
|
||
|
def _eintr_retry_call(func, *args):
|
||
|
while True:
|
||
|
try:
|
||
|
return func(*args)
|
||
|
except (OSError, IOError), e:
|
||
|
if e.errno == errno.EINTR:
|
||
|
continue
|
||
|
raise
|
||
|
|
||
|
|
||
|
def call(*popenargs, **kwargs):
|
||
|
"""Run command with arguments. Wait for command to complete, then
|
||
|
return the returncode attribute.
|
||
|
|
||
|
The arguments are the same as for the Popen constructor. Example:
|
||
|
|
||
|
retcode = call(["ls", "-l"])
|
||
|
"""
|
||
|
return Popen(*popenargs, **kwargs).wait()
|
||
|
|
||
|
|
||
|
def check_call(*popenargs, **kwargs):
|
||
|
"""Run command with arguments. Wait for command to complete. If
|
||
|
the exit code was zero then return, otherwise raise
|
||
|
CalledProcessError. The CalledProcessError object will have the
|
||
|
return code in the returncode attribute.
|
||
|
|
||
|
The arguments are the same as for the Popen constructor. Example:
|
||
|
|
||
|
check_call(["ls", "-l"])
|
||
|
"""
|
||
|
retcode = call(*popenargs, **kwargs)
|
||
|
if retcode:
|
||
|
cmd = kwargs.get("args")
|
||
|
if cmd is None:
|
||
|
cmd = popenargs[0]
|
||
|
raise CalledProcessError(retcode, cmd)
|
||
|
return 0
|
||
|
|
||
|
|
||
|
def check_output(*popenargs, **kwargs):
|
||
|
r"""Run command with arguments and return its output as a byte string.
|
||
|
|
||
|
If the exit code was non-zero it raises a CalledProcessError. The
|
||
|
CalledProcessError object will have the return code in the returncode
|
||
|
attribute and output in the output attribute.
|
||
|
|
||
|
The arguments are the same as for the Popen constructor. Example:
|
||
|
|
||
|
>>> check_output(["ls", "-l", "/dev/null"])
|
||
|
'crw-rw-rw- 1 root root 1, 3 Oct 18 2007 /dev/null\n'
|
||
|
|
||
|
The stdout argument is not allowed as it is used internally.
|
||
|
To capture standard error in the result, use stderr=STDOUT.
|
||
|
|
||
|
>>> check_output(["/bin/sh", "-c",
|
||
|
... "ls -l non_existent_file ; exit 0"],
|
||
|
... stderr=STDOUT)
|
||
|
'ls: non_existent_file: No such file or directory\n'
|
||
|
"""
|
||
|
if 'stdout' in kwargs:
|
||
|
raise ValueError('stdout argument not allowed, it will be overridden.')
|
||
|
process = Popen(stdout=PIPE, *popenargs, **kwargs)
|
||
|
output, unused_err = process.communicate()
|
||
|
retcode = process.poll()
|
||
|
if retcode:
|
||
|
cmd = kwargs.get("args")
|
||
|
if cmd is None:
|
||
|
cmd = popenargs[0]
|
||
|
raise CalledProcessError(retcode, cmd, output=output)
|
||
|
return output
|
||
|
|
||
|
|
||
|
def list2cmdline(seq):
|
||
|
"""
|
||
|
Translate a sequence of arguments into a command line
|
||
|
string, using the same rules as the MS C runtime:
|
||
|
|
||
|
1) Arguments are delimited by white space, which is either a
|
||
|
space or a tab.
|
||
|
|
||
|
2) A string surrounded by double quotation marks is
|
||
|
interpreted as a single argument, regardless of white space
|
||
|
contained within. A quoted string can be embedded in an
|
||
|
argument.
|
||
|
|
||
|
3) A double quotation mark preceded by a backslash is
|
||
|
interpreted as a literal double quotation mark.
|
||
|
|
||
|
4) Backslashes are interpreted literally, unless they
|
||
|
immediately precede a double quotation mark.
|
||
|
|
||
|
5) If backslashes immediately precede a double quotation mark,
|
||
|
every pair of backslashes is interpreted as a literal
|
||
|
backslash. If the number of backslashes is odd, the last
|
||
|
backslash escapes the next double quotation mark as
|
||
|
described in rule 3.
|
||
|
"""
|
||
|
|
||
|
# See
|
||
|
# http://msdn.microsoft.com/en-us/library/17w5ykft.aspx
|
||
|
# or search http://msdn.microsoft.com for
|
||
|
# "Parsing C++ Command-Line Arguments"
|
||
|
result = []
|
||
|
needquote = False
|
||
|
for arg in seq:
|
||
|
bs_buf = []
|
||
|
|
||
|
# Add a space to separate this argument from the others
|
||
|
if result:
|
||
|
result.append(' ')
|
||
|
|
||
|
needquote = (" " in arg) or ("\t" in arg) or not arg
|
||
|
if needquote:
|
||
|
result.append('"')
|
||
|
|
||
|
for c in arg:
|
||
|
if c == '\\':
|
||
|
# Don't know if we need to double yet.
|
||
|
bs_buf.append(c)
|
||
|
elif c == '"':
|
||
|
# Double backslashes.
|
||
|
result.append('\\' * len(bs_buf) * 2)
|
||
|
bs_buf = []
|
||
|
result.append('\\"')
|
||
|
else:
|
||
|
# Normal char
|
||
|
if bs_buf:
|
||
|
result.extend(bs_buf)
|
||
|
bs_buf = []
|
||
|
result.append(c)
|
||
|
|
||
|
# Add remaining backslashes, if any.
|
||
|
if bs_buf:
|
||
|
result.extend(bs_buf)
|
||
|
|
||
|
if needquote:
|
||
|
result.extend(bs_buf)
|
||
|
result.append('"')
|
||
|
|
||
|
return ''.join(result)
|
||
|
|
||
|
|
||
|
class Popen(object):
|
||
|
|
||
|
def __init__(self, args, bufsize=0, executable=None,
|
||
|
stdin=None, stdout=None, stderr=None,
|
||
|
preexec_fn=None, close_fds=False, shell=False,
|
||
|
cwd=None, env=None, universal_newlines=False,
|
||
|
startupinfo=None, creationflags=0):
|
||
|
"""Create new Popen instance."""
|
||
|
_cleanup()
|
||
|
|
||
|
self._child_created = False
|
||
|
if not isinstance(bufsize, (int, long)):
|
||
|
raise TypeError("bufsize must be an integer")
|
||
|
|
||
|
if mswindows:
|
||
|
if preexec_fn is not None:
|
||
|
raise ValueError("preexec_fn is not supported on Windows "
|
||
|
"platforms")
|
||
|
if close_fds and (stdin is not None or stdout is not None or
|
||
|
stderr is not None):
|
||
|
raise ValueError("close_fds is not supported on Windows "
|
||
|
"platforms if you redirect "
|
||
|
"stdin/stdout/stderr")
|
||
|
else:
|
||
|
# POSIX
|
||
|
if startupinfo is not None:
|
||
|
raise ValueError("startupinfo is only supported on Windows "
|
||
|
"platforms")
|
||
|
if creationflags != 0:
|
||
|
raise ValueError("creationflags is only supported on Windows "
|
||
|
"platforms")
|
||
|
|
||
|
self.stdin = None
|
||
|
self.stdout = None
|
||
|
self.stderr = None
|
||
|
self.pid = None
|
||
|
self.returncode = None
|
||
|
self.universal_newlines = universal_newlines
|
||
|
|
||
|
# Input and output objects. The general principle is like
|
||
|
# this:
|
||
|
#
|
||
|
# Parent Child
|
||
|
# ------ -----
|
||
|
# p2cwrite ---stdin---> p2cread
|
||
|
# c2pread <--stdout--- c2pwrite
|
||
|
# errread <--stderr--- errwrite
|
||
|
#
|
||
|
# On POSIX, the child objects are file descriptors. On
|
||
|
# Windows, these are Windows file handles. The parent objects
|
||
|
# are file descriptors on both platforms. The parent objects
|
||
|
# are None when not using PIPEs. The child objects are None
|
||
|
# when not redirecting.
|
||
|
|
||
|
(p2cread, p2cwrite,
|
||
|
c2pread, c2pwrite,
|
||
|
errread, errwrite) = self._get_handles(stdin, stdout, stderr)
|
||
|
|
||
|
self._execute_child(args, executable, preexec_fn, close_fds,
|
||
|
cwd, env, universal_newlines,
|
||
|
startupinfo, creationflags, shell,
|
||
|
p2cread, p2cwrite,
|
||
|
c2pread, c2pwrite,
|
||
|
errread, errwrite)
|
||
|
|
||
|
if mswindows:
|
||
|
if p2cwrite is not None:
|
||
|
p2cwrite = msvcrt.open_osfhandle(p2cwrite.Detach(), 0)
|
||
|
if c2pread is not None:
|
||
|
c2pread = msvcrt.open_osfhandle(c2pread.Detach(), 0)
|
||
|
if errread is not None:
|
||
|
errread = msvcrt.open_osfhandle(errread.Detach(), 0)
|
||
|
|
||
|
if p2cwrite is not None:
|
||
|
self.stdin = os.fdopen(p2cwrite, 'wb', bufsize)
|
||
|
if c2pread is not None:
|
||
|
if universal_newlines:
|
||
|
self.stdout = os.fdopen(c2pread, 'rU', bufsize)
|
||
|
else:
|
||
|
self.stdout = os.fdopen(c2pread, 'rb', bufsize)
|
||
|
if errread is not None:
|
||
|
if universal_newlines:
|
||
|
self.stderr = os.fdopen(errread, 'rU', bufsize)
|
||
|
else:
|
||
|
self.stderr = os.fdopen(errread, 'rb', bufsize)
|
||
|
|
||
|
def _translate_newlines(self, data):
|
||
|
data = data.replace("\r\n", "\n")
|
||
|
data = data.replace("\r", "\n")
|
||
|
return data
|
||
|
|
||
|
def __del__(self, _maxint=sys.maxint, _active=_active):
|
||
|
# If __init__ hasn't had a chance to execute (e.g. if it
|
||
|
# was passed an undeclared keyword argument), we don't
|
||
|
# have a _child_created attribute at all.
|
||
|
if not getattr(self, '_child_created', False):
|
||
|
# We didn't get to successfully create a child process.
|
||
|
return
|
||
|
# In case the child hasn't been waited on, check if it's done.
|
||
|
self._internal_poll(_deadstate=_maxint)
|
||
|
if self.returncode is None and _active is not None:
|
||
|
# Child is still running, keep us alive until we can wait on it.
|
||
|
_active.append(self)
|
||
|
|
||
|
def communicate(self, input=None):
|
||
|
"""Interact with process: Send data to stdin. Read data from
|
||
|
stdout and stderr, until end-of-file is reached. Wait for
|
||
|
process to terminate. The optional input argument should be a
|
||
|
string to be sent to the child process, or None, if no data
|
||
|
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, 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):
|
||
|
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
|
||
|
"""
|
||
|
if stdin is None and stdout is None and stderr is None:
|
||
|
return (None, None, None, None, None, None)
|
||
|
|
||
|
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):
|
||
|
p2cread = msvcrt.get_osfhandle(stdin)
|
||
|
else:
|
||
|
# Assuming file-like object
|
||
|
p2cread = msvcrt.get_osfhandle(stdin.fileno())
|
||
|
p2cread = self._make_inheritable(p2cread)
|
||
|
|
||
|
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):
|
||
|
c2pwrite = msvcrt.get_osfhandle(stdout)
|
||
|
else:
|
||
|
# Assuming file-like object
|
||
|
c2pwrite = msvcrt.get_osfhandle(stdout.fileno())
|
||
|
c2pwrite = self._make_inheritable(c2pwrite)
|
||
|
|
||
|
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):
|
||
|
errwrite = msvcrt.get_osfhandle(stderr)
|
||
|
else:
|
||
|
# Assuming file-like object
|
||
|
errwrite = msvcrt.get_osfhandle(stderr.fileno())
|
||
|
errwrite = self._make_inheritable(errwrite)
|
||
|
|
||
|
return (p2cread, p2cwrite,
|
||
|
c2pread, c2pwrite,
|
||
|
errread, errwrite)
|
||
|
|
||
|
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,
|
||
|
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
|
||
|
|
||
|
# Start the process
|
||
|
try:
|
||
|
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:
|
||
|
p2cread.Close()
|
||
|
if c2pwrite is not None:
|
||
|
c2pwrite.Close()
|
||
|
if errwrite is not None:
|
||
|
errwrite.Close()
|
||
|
|
||
|
# 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, e:
|
||
|
if e.errno != errno.EPIPE:
|
||
|
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
|
||
|
"""
|
||
|
_subprocess.TerminateProcess(self._handle, 1)
|
||
|
|
||
|
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
|
||
|
"""
|
||
|
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()
|
||
|
elif isinstance(stdin, int):
|
||
|
p2cread = stdin
|
||
|
else:
|
||
|
# Assuming file-like object
|
||
|
p2cread = stdin.fileno()
|
||
|
|
||
|
if stdout is None:
|
||
|
pass
|
||
|
elif stdout == PIPE:
|
||
|
c2pread, c2pwrite = self.pipe_cloexec()
|
||
|
elif isinstance(stdout, int):
|
||
|
c2pwrite = stdout
|
||
|
else:
|
||
|
# Assuming file-like object
|
||
|
c2pwrite = stdout.fileno()
|
||
|
|
||
|
if stderr is None:
|
||
|
pass
|
||
|
elif stderr == PIPE:
|
||
|
errread, errwrite = self.pipe_cloexec()
|
||
|
elif stderr == STDOUT:
|
||
|
errwrite = c2pwrite
|
||
|
elif isinstance(stderr, int):
|
||
|
errwrite = stderr
|
||
|
else:
|
||
|
# Assuming file-like object
|
||
|
errwrite = stderr.fileno()
|
||
|
|
||
|
return (p2cread, p2cwrite,
|
||
|
c2pread, c2pwrite,
|
||
|
errread, errwrite)
|
||
|
|
||
|
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
|
||
|
|
||
|
def _execute_child(self, args, executable, preexec_fn, close_fds,
|
||
|
cwd, env, universal_newlines,
|
||
|
startupinfo, creationflags, shell,
|
||
|
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]
|
||
|
|
||
|
# 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:
|
||
|
gc_was_enabled = gc.isenabled()
|
||
|
# Disable gc to avoid bug where gc -> file_dealloc ->
|
||
|
# write to stderr -> hang.
|
||
|
# http://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 = set([None])
|
||
|
for fd in [p2cread, c2pwrite, errwrite]:
|
||
|
if fd not in closed and fd > 2:
|
||
|
os.close(fd)
|
||
|
closed.add(fd)
|
||
|
|
||
|
# Close all other fds, if asked for
|
||
|
if close_fds:
|
||
|
self._close_fds(but=errpipe_write)
|
||
|
|
||
|
if cwd is not None:
|
||
|
os.chdir(cwd)
|
||
|
|
||
|
if preexec_fn:
|
||
|
preexec_fn()
|
||
|
|
||
|
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))
|
||
|
|
||
|
# 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)
|
||
|
|
||
|
if p2cread is not None and p2cwrite is not None:
|
||
|
os.close(p2cread)
|
||
|
if c2pwrite is not None and c2pread is not None:
|
||
|
os.close(c2pwrite)
|
||
|
if errwrite is not None and errread is not None:
|
||
|
os.close(errwrite)
|
||
|
|
||
|
# Wait for exec to fail or succeed; possibly raising exception
|
||
|
# Exception limited to 1M
|
||
|
data = _eintr_retry_call(os.read, errpipe_read, 1048576)
|
||
|
finally:
|
||
|
# 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, e:
|
||
|
if e.errno != errno.ECHILD:
|
||
|
raise
|
||
|
child_exception = pickle.loads(data)
|
||
|
for fd in (p2cwrite, c2pread, errread):
|
||
|
if fd is not None:
|
||
|
os.close(fd)
|
||
|
raise child_exception
|
||
|
|
||
|
def _handle_exitstatus(self, sts, _WIFSIGNALED=os.WIFSIGNALED,
|
||
|
_WTERMSIG=os.WTERMSIG, _WIFEXITED=os.WIFEXITED,
|
||
|
_WEXITSTATUS=os.WEXITSTATUS):
|
||
|
# 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)
|
||
|
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):
|
||
|
"""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:
|
||
|
if _deadstate is not None:
|
||
|
self.returncode = _deadstate
|
||
|
return self.returncode
|
||
|
|
||
|
def wait(self):
|
||
|
"""Wait for child process to terminate. Returns returncode
|
||
|
attribute."""
|
||
|
if self.returncode is None:
|
||
|
try:
|
||
|
pid, sts = _eintr_retry_call(os.waitpid, self.pid, 0)
|
||
|
except OSError, 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.
|
||
|
sts = 0
|
||
|
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, 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, 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()
|