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Fixing python 2.7 windows unicode issue with ``subprocess.Popen``.
# -*- coding: utf-8 -*-
## Copyright (C) 2021 Valentin Lab
##
## Redistribution and use in source and binary forms, with or without
## modification, are permitted provided that the following conditions
## are met:
##
## 1. Redistributions of source code must retain the above copyright
## notice, this list of conditions and the following disclaimer.
##
## 2. Redistributions in binary form must reproduce the above
## copyright notice, this list of conditions and the following
## disclaimer in the documentation and/or other materials provided
## with the distribution.
##
## 3. Neither the name of the copyright holder nor the names of its
## contributors may be used to endorse or promote products derived
## from this software without specific prior written permission.
##
## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
## "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
## LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
## FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
## COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
## INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
## (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
## SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
## HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
## STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
## ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
## OF THE POSSIBILITY OF SUCH DAMAGE.
##
## issue: https://bugs.python.org/issue19264
import ctypes
import subprocess
import _subprocess
from ctypes import byref, windll, c_char_p, c_wchar_p, c_void_p, \
Structure, sizeof, c_wchar, WinError
from ctypes.wintypes import BYTE, WORD, LPWSTR, BOOL, DWORD, LPVOID, \
HANDLE
##
## Types
##
CREATE_UNICODE_ENVIRONMENT = 0x00000400
LPCTSTR = c_char_p
LPTSTR = c_wchar_p
LPSECURITY_ATTRIBUTES = c_void_p
LPBYTE = ctypes.POINTER(BYTE)
class STARTUPINFOW(Structure):
_fields_ = [
("cb", DWORD), ("lpReserved", LPWSTR),
("lpDesktop", LPWSTR), ("lpTitle", LPWSTR),
("dwX", DWORD), ("dwY", DWORD),
("dwXSize", DWORD), ("dwYSize", DWORD),
("dwXCountChars", DWORD), ("dwYCountChars", DWORD),
("dwFillAtrribute", DWORD), ("dwFlags", DWORD),
("wShowWindow", WORD), ("cbReserved2", WORD),
("lpReserved2", LPBYTE), ("hStdInput", HANDLE),
("hStdOutput", HANDLE), ("hStdError", HANDLE),
]
LPSTARTUPINFOW = ctypes.POINTER(STARTUPINFOW)
class PROCESS_INFORMATION(Structure):
_fields_ = [
("hProcess", HANDLE), ("hThread", HANDLE),
("dwProcessId", DWORD), ("dwThreadId", DWORD),
]
LPPROCESS_INFORMATION = ctypes.POINTER(PROCESS_INFORMATION)
class DUMMY_HANDLE(ctypes.c_void_p):
def __init__(self, *a, **kw):
super(DUMMY_HANDLE, self).__init__(*a, **kw)
self.closed = False
def Close(self):
if not self.closed:
windll.kernel32.CloseHandle(self)
self.closed = True
def __int__(self):
return self.value
CreateProcessW = windll.kernel32.CreateProcessW
CreateProcessW.argtypes = [
LPCTSTR, LPTSTR, LPSECURITY_ATTRIBUTES,
LPSECURITY_ATTRIBUTES, BOOL, DWORD, LPVOID, LPCTSTR,
LPSTARTUPINFOW, LPPROCESS_INFORMATION,
]
CreateProcessW.restype = BOOL
##
## Patched functions/classes
##
def CreateProcess(executable, args, _p_attr, _t_attr,
inherit_handles, creation_flags, env, cwd,
startup_info):
"""Create a process supporting unicode executable and args for win32
Python implementation of CreateProcess using CreateProcessW for Win32
"""
si = STARTUPINFOW(
dwFlags=startup_info.dwFlags,
wShowWindow=startup_info.wShowWindow,
cb=sizeof(STARTUPINFOW),
## XXXvlab: not sure of the casting here to ints.
hStdInput=int(startup_info.hStdInput),
hStdOutput=int(startup_info.hStdOutput),
hStdError=int(startup_info.hStdError),
)
wenv = None
if env is not None:
## LPCWSTR seems to be c_wchar_p, so let's say CWSTR is c_wchar
env = (unicode("").join([
unicode("%s=%s\0") % (k, v)
for k, v in env.items()])) + unicode("\0")
wenv = (c_wchar * len(env))()
wenv.value = env
pi = PROCESS_INFORMATION()
creation_flags |= CREATE_UNICODE_ENVIRONMENT
if CreateProcessW(executable, args, None, None,
inherit_handles, creation_flags,
wenv, cwd, byref(si), byref(pi)):
return (DUMMY_HANDLE(pi.hProcess), DUMMY_HANDLE(pi.hThread),
pi.dwProcessId, pi.dwThreadId)
raise WinError()
class Popen(subprocess.Popen):
"""This superseeds Popen and corrects a bug in cPython 2.7 implem"""
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):
"""Code from part of _execute_child from Python 2.7 (9fbb65e)
There are only 2 little changes concerning the construction of
the the final string in shell mode: we preempt the creation of
the command string when shell is True, because original function
will try to encode unicode args which we want to avoid to be able to
sending it as-is to ``CreateProcess``.
"""
if not isinstance(args, subprocess.types.StringTypes):
args = subprocess.list2cmdline(args)
if startupinfo is None:
startupinfo = subprocess.STARTUPINFO()
if shell:
startupinfo.dwFlags |= _subprocess.STARTF_USESHOWWINDOW
startupinfo.wShowWindow = _subprocess.SW_HIDE
comspec = os.environ.get("COMSPEC", unicode("cmd.exe"))
args = unicode('{} /c "{}"').format(comspec, args)
if (_subprocess.GetVersion() >= 0x80000000 or
os.path.basename(comspec).lower() == "command.com"):
w9xpopen = self._find_w9xpopen()
args = unicode('"%s" %s') % (w9xpopen, args)
creationflags |= _subprocess.CREATE_NEW_CONSOLE
super(Popen, self)._execute_child(args, executable,
preexec_fn, close_fds, cwd, env, universal_newlines,
startupinfo, creationflags, False, to_close, p2cread,
p2cwrite, c2pread, c2pwrite, errread, errwrite)
_subprocess.CreateProcess = CreateProcess
@vaab
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vaab commented Feb 9, 2021

@exarkun Here you are. Is that good for you ?

@exarkun
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exarkun commented Feb 9, 2021

@vaab That is perfect. Thank you kindly.

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