blob: 24888a53dc61e3f71fd51fbbc6bbab9c107f8b66 [file] [log] [blame]
#!/usr/bin/env python
# Copyright (c) 2016 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
from __future__ import print_function
import os
import sys
from third_party import colorama
IS_TTY = None
OUT_TYPE = 'unknown'
def init():
# should_wrap instructs colorama to wrap stdout/stderr with an ASNI colorcode
# interpreter that converts them to SetConsoleTextAttribute calls. This only
# should be True in cases where we're connected to cmd.exe's console. Setting
# this to True on non-windows systems has no effect.
should_wrap = False
IS_TTY = sys.stdout.isatty()
if IS_TTY:
# Yay! We detected a console in the normal way. It doesn't really matter
# if it's windows or not, we win.
OUT_TYPE = 'console'
should_wrap = True
elif sys.platform.startswith('win'):
# assume this is some sort of file
OUT_TYPE = 'file (win)'
import msvcrt
import ctypes
h = msvcrt.get_osfhandle(sys.stdout.fileno())
# h is the win32 HANDLE for stdout.
ftype = ctypes.windll.kernel32.GetFileType(h)
if ftype == 2: # FILE_TYPE_CHAR
# This is a normal cmd console, but we'll only get here if we're running
# inside a `git command` which is actually git->bash->command. Not sure
# why isatty doesn't detect this case.
OUT_TYPE = 'console (cmd via msys)'
IS_TTY = True
should_wrap = True
elif ftype == 3: # FILE_TYPE_PIPE
OUT_TYPE = 'pipe (win)'
# This is some kind of pipe on windows. This could either be a real pipe
# or this could be msys using a pipe to emulate a pty. We use the same
# algorithm that msys-git uses to determine if it's connected to a pty or
# not.
# This function and the structures are defined in the MSDN documentation
# using the same names.
def NT_SUCCESS(status):
# The first two bits of status are the severity. The success
# severities are 0 and 1, and the !success severities are 2 and 3.
# Therefore since ctypes interprets the default restype of the call
# to be an 'C int' (which is guaranteed to be signed 32 bits), All
# success codes are positive, and all !success codes are negative.
return status >= 0
class UNICODE_STRING(ctypes.Structure):
_fields_ = [('Length', ctypes.c_ushort),
('MaximumLength', ctypes.c_ushort),
('Buffer', ctypes.c_wchar_p)]
class OBJECT_NAME_INFORMATION(ctypes.Structure):
_fields_ = [('Name', UNICODE_STRING),
('NameBuffer', ctypes.c_wchar_p)]
buf = ctypes.create_string_buffer(1024)
# Ask NT what the name of the object our stdout HANDLE is. It would be
# possible to use GetFileInformationByHandleEx, but it's only available
# on Vista+. If you're reading this in 2017 or later, feel free to
# refactor this out.
# The '1' here is ObjectNameInformation
if NT_SUCCESS(ctypes.windll.ntdll.NtQueryObject(h, 1, buf, len(buf)-2,
out = OBJECT_NAME_INFORMATION.from_buffer(buf)
name = out.Name.Buffer.split('\\')[-1]
IS_TTY = name.startswith('msys-') and '-pty' in name
if IS_TTY:
OUT_TYPE = 'bash (msys)'
# A normal file, or an unknown file type.
# This is non-windows, so we trust isatty.
OUT_TYPE = 'pipe or file'
if __name__ == '__main__':
print('IS_TTY:', IS_TTY)
print('OUT_TYPE:', OUT_TYPE)