view mercurial/win32.py @ 50338:81c7d04f4722 stable

match: match explicit file using a set The matcher as all the logic to do quick comparison against explicit patterns, however the pattern matcher was shadowing the code using that set and used the compiled regex pattern in all cases, which is quite slow. We restore the usage of the set based matching to boost performance. Building the regexp is still consuming a large amount of time (actually, the majority of the time), which is still silly. Maybe using re2 would help that, but this is a quest for another adventure. Another path to improve this is to have a pattern type dedicated to match the exact path to a file only (not a directory). This pattern could use the set matching only and be skipped in the regex all together. Benchmarks ========== In the following benchmark we are comparing the `hg cat` and `hg files` run time when matching against all files in the repository. They are run: - without the rust extensions - with the standard python engine (so without re2) Performance improvement in this series -------------------------------------- ###### hg files ############################################################### ### mercurial-2018-08-01-zstd-sparse-revlog ### sorted base-changeset: 0.230092 seconds prev-changeset: 0.230069 seconds this-changeset: 0.211425 seconds (-8.36%) ### mercurial-2018-08-01-zstd-sparse-revlog ### shuffled base-changeset: 0.234235 seconds prev-changeset: 0.231165 seconds (-1.38%) this-changeset: 0.212300 seconds (-9.43%) ### pypy-2018-08-01-zstd-sparse-revlog ### sorted base-changeset: 0.613567 seconds prev-changeset: 0.616799 seconds this-changeset: 0.510852 seconds (-16.82%) ### pypy-2018-08-01-zstd-sparse-revlog ### shuffled base-changeset: 0.801880 seconds prev-changeset: 0.616393 seconds (-23.22%) this-changeset: 0.511903 seconds (-36.23%) ### netbeans-2018-08-01-zstd-sparse-revlog ### sorted base-changeset: 21.541828 seconds prev-changeset: 21.586773 seconds this-changeset: 13.648347 seconds (-36.76%) ### netbeans-2018-08-01-zstd-sparse-revlog ### shuffled base-changeset: 172.759857 seconds prev-changeset: 21.908197 seconds (-87.32%) this-changeset: 13.945110 seconds (-91.93%) ### mozilla-central-2018-08-01-zstd-sparse-revlog ### sorted base-changeset: 62.474221 seconds prev-changeset: 61.279490 seconds (-1.22%) this-changeset: 29.529469 seconds (-52.40%) ### mozilla-central-2018-08-01-zstd-sparse-revlog ### shuffled base-changeset: 1364.180218 seconds prev-changeset: 62.473549 seconds (-95.40%) this-changeset: 30.625249 seconds (-97.75%) ###### hg cat ################################################################# ### mercurial-2018-08-01-zstd-sparse-revlog ### sorted base-changeset: 0.764407 seconds prev-changeset: 0.763883 seconds this-changeset: 0.737326 seconds (-3.68%) ### mercurial-2018-08-01-zstd-sparse-revlog ### shuffled base-changeset: 0.768924 seconds prev-changeset: 0.765848 seconds this-changeset: 0.174d0b seconds (-4.44%) ### pypy-2018-08-01-zstd-sparse-revlog ### sorted base-changeset: 2.065220 seconds prev-changeset: 2.070498 seconds this-changeset: 1.939482 seconds (-6.08%) ### pypy-2018-08-01-zstd-sparse-revlog ### shuffled base-changeset: 2.276388 seconds prev-changeset: 2.069197 seconds (-9.15%) this-changeset: 1.931746 seconds (-15.19%) ### netbeans-2018-08-01-zstd-sparse-revlog ### sorted base-changeset: 40.967983 seconds prev-changeset: 41.392423 seconds this-changeset: 32.181681 seconds (-22.20%) ### netbeans-2018-08-01-zstd-sparse-revlog ### shuffled base-changeset: 216.388709 seconds prev-changeset: 41.648689 seconds (-80.88%) this-changeset: 32.580817 seconds (-85.04%) ### mozilla-central-2018-08-01-zstd-sparse-revlog ### sorted base-changeset: 105.228510 seconds prev-changeset: 103.315670 seconds (-1.23%) this-changeset: 69.416118 seconds (-33.64%) ### mozilla-central-2018-08-01-zstd-sparse-revlog ### shuffled base-changeset: 1448.722784 seconds prev-changeset: 104.369358 seconds (-92.80%) this-changeset: 70.554789 seconds (-95.13%) Different way to list the same data with this revision ------------------------------------------------------ ###### hg files ############################################################### ### mercurial-2018-08-01-zstd-sparse-revlog root: 0.119182 seconds glob: 0.120697 seconds (+1.27%) sorted: 0.211425 seconds (+77.40%) shuffled: 0.212300 seconds (+78.13%) ### pypy-2018-08-01-zstd-sparse-revlog root: 0.121986 seconds glob: 0.124822 seconds (+2.32%) sorted: 0.510852 seconds (+318.78%) shuffled: 0.511903 seconds (+319.64%) ### netbeans-2018-08-01-zstd-sparse-revlog root: 0.173984 seconds glob: 0.227203 seconds (+30.59%) sorted: 13.648347 seconds (+7744.59%) shuffled: 13.945110 seconds (+7915.16%) ### mozilla-central-2018-08-01-zstd-sparse-revlog root: 0.366463 seconds glob: 0.491030 seconds (+33.99%) sorted: 29.529469 seconds (+7957.96%) shuffled: 30.625249 seconds (+8256.97%) ###### hg cat ################################################################# ### mercurial-2018-08-01-zstd-sparse-revlog glob: 0.647471 seconds root: 0.643120 seconds shuffled: 0.174d0b seconds (+13.92%) sorted: 0.737326 seconds (+13.88%) ### mozilla-central-2018-08-01-zstd-sparse-revlog glob: 40.596983 seconds root: 40.129136 seconds shuffled: 70.554789 seconds (+73.79%) sorted: 69.416118 seconds (+70.99%) ### netbeans-2018-08-01-zstd-sparse-revlog glob: 18.777924 seconds root: 18.613905 seconds shuffled: 32.580817 seconds (+73.51%) sorted: 32.181681 seconds (+71.38%) ### pypy-2018-08-01-zstd-sparse-revlog glob: 1.555319 seconds root: 1.536534 seconds shuffled: 1.931746 seconds (+24.20%) sorted: 1.939482 seconds (+24.70%)
author Pierre-Yves David <pierre-yves.david@octobus.net>
date Sat, 01 Apr 2023 05:58:59 +0200
parents a9faacdc5943
children 493034cc3265
line wrap: on
line source

# win32.py - utility functions that use win32 API
#
# Copyright 2005-2009 Olivia Mackall <olivia@selenic.com> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.


import ctypes
import ctypes.wintypes as wintypes
import errno
import msvcrt
import os
import random
import subprocess

from typing import (
    List,
    NoReturn,
    Optional,
    Tuple,
)

from . import (
    encoding,
    pycompat,
)

# pytype: disable=module-attr
_kernel32 = ctypes.windll.kernel32
_advapi32 = ctypes.windll.advapi32
_user32 = ctypes.windll.user32
_crypt32 = ctypes.windll.crypt32
# pytype: enable=module-attr

_BOOL = ctypes.c_long
_WORD = ctypes.c_ushort
_DWORD = ctypes.c_ulong
_UINT = ctypes.c_uint
_LONG = ctypes.c_long
_LPCSTR = _LPSTR = ctypes.c_char_p
_HANDLE = ctypes.c_void_p
_HWND = _HANDLE
_PCCERT_CONTEXT = ctypes.c_void_p
_MAX_PATH = wintypes.MAX_PATH

_INVALID_HANDLE_VALUE = _HANDLE(-1).value

# GetLastError
_ERROR_SUCCESS = 0
_ERROR_NO_MORE_FILES = 18
_ERROR_INVALID_PARAMETER = 87
_ERROR_BROKEN_PIPE = 109
_ERROR_INSUFFICIENT_BUFFER = 122
_ERROR_NO_DATA = 232

# WPARAM is defined as UINT_PTR (unsigned type)
# LPARAM is defined as LONG_PTR (signed type)
if ctypes.sizeof(ctypes.c_long) == ctypes.sizeof(ctypes.c_void_p):
    _WPARAM = ctypes.c_ulong
    _LPARAM = ctypes.c_long
elif ctypes.sizeof(ctypes.c_longlong) == ctypes.sizeof(ctypes.c_void_p):
    _WPARAM = ctypes.c_ulonglong
    _LPARAM = ctypes.c_longlong


class _FILETIME(ctypes.Structure):
    _fields_ = [('dwLowDateTime', _DWORD), ('dwHighDateTime', _DWORD)]


class _BY_HANDLE_FILE_INFORMATION(ctypes.Structure):
    _fields_ = [
        ('dwFileAttributes', _DWORD),
        ('ftCreationTime', _FILETIME),
        ('ftLastAccessTime', _FILETIME),
        ('ftLastWriteTime', _FILETIME),
        ('dwVolumeSerialNumber', _DWORD),
        ('nFileSizeHigh', _DWORD),
        ('nFileSizeLow', _DWORD),
        ('nNumberOfLinks', _DWORD),
        ('nFileIndexHigh', _DWORD),
        ('nFileIndexLow', _DWORD),
    ]


# CreateFile
_FILE_SHARE_READ = 0x00000001
_FILE_SHARE_WRITE = 0x00000002
_FILE_SHARE_DELETE = 0x00000004

_OPEN_EXISTING = 3

_FILE_FLAG_BACKUP_SEMANTICS = 0x02000000

# SetFileAttributes
_FILE_ATTRIBUTE_NORMAL = 0x80
_FILE_ATTRIBUTE_NOT_CONTENT_INDEXED = 0x2000

# Process Security and Access Rights
_PROCESS_QUERY_INFORMATION = 0x0400

# GetExitCodeProcess
_STILL_ACTIVE = 259


class _STARTUPINFO(ctypes.Structure):
    _fields_ = [
        ('cb', _DWORD),
        ('lpReserved', _LPSTR),
        ('lpDesktop', _LPSTR),
        ('lpTitle', _LPSTR),
        ('dwX', _DWORD),
        ('dwY', _DWORD),
        ('dwXSize', _DWORD),
        ('dwYSize', _DWORD),
        ('dwXCountChars', _DWORD),
        ('dwYCountChars', _DWORD),
        ('dwFillAttribute', _DWORD),
        ('dwFlags', _DWORD),
        ('wShowWindow', _WORD),
        ('cbReserved2', _WORD),
        ('lpReserved2', ctypes.c_char_p),
        ('hStdInput', _HANDLE),
        ('hStdOutput', _HANDLE),
        ('hStdError', _HANDLE),
    ]


class _PROCESS_INFORMATION(ctypes.Structure):
    _fields_ = [
        ('hProcess', _HANDLE),
        ('hThread', _HANDLE),
        ('dwProcessId', _DWORD),
        ('dwThreadId', _DWORD),
    ]


_CREATE_NO_WINDOW = 0x08000000
_SW_HIDE = 0


class _COORD(ctypes.Structure):
    _fields_ = [('X', ctypes.c_short), ('Y', ctypes.c_short)]


class _SMALL_RECT(ctypes.Structure):
    _fields_ = [
        ('Left', ctypes.c_short),
        ('Top', ctypes.c_short),
        ('Right', ctypes.c_short),
        ('Bottom', ctypes.c_short),
    ]


class _CONSOLE_SCREEN_BUFFER_INFO(ctypes.Structure):
    _fields_ = [
        ('dwSize', _COORD),
        ('dwCursorPosition', _COORD),
        ('wAttributes', _WORD),
        ('srWindow', _SMALL_RECT),
        ('dwMaximumWindowSize', _COORD),
    ]


_STD_OUTPUT_HANDLE = _DWORD(-11).value
_STD_ERROR_HANDLE = _DWORD(-12).value

# CERT_TRUST_STATUS dwErrorStatus
CERT_TRUST_IS_PARTIAL_CHAIN = 0x10000

# CertCreateCertificateContext encodings
X509_ASN_ENCODING = 0x00000001
PKCS_7_ASN_ENCODING = 0x00010000

# These structs are only complete enough to achieve what we need.
class CERT_CHAIN_CONTEXT(ctypes.Structure):
    _fields_ = (
        ("cbSize", _DWORD),
        # CERT_TRUST_STATUS struct
        ("dwErrorStatus", _DWORD),
        ("dwInfoStatus", _DWORD),
        ("cChain", _DWORD),
        ("rgpChain", ctypes.c_void_p),
        ("cLowerQualityChainContext", _DWORD),
        ("rgpLowerQualityChainContext", ctypes.c_void_p),
        ("fHasRevocationFreshnessTime", _BOOL),
        ("dwRevocationFreshnessTime", _DWORD),
    )


class CERT_USAGE_MATCH(ctypes.Structure):
    _fields_ = (
        ("dwType", _DWORD),
        # CERT_ENHKEY_USAGE struct
        ("cUsageIdentifier", _DWORD),
        ("rgpszUsageIdentifier", ctypes.c_void_p),  # LPSTR *
    )


class CERT_CHAIN_PARA(ctypes.Structure):
    _fields_ = (
        ("cbSize", _DWORD),
        ("RequestedUsage", CERT_USAGE_MATCH),
        ("RequestedIssuancePolicy", CERT_USAGE_MATCH),
        ("dwUrlRetrievalTimeout", _DWORD),
        ("fCheckRevocationFreshnessTime", _BOOL),
        ("dwRevocationFreshnessTime", _DWORD),
        ("pftCacheResync", ctypes.c_void_p),  # LPFILETIME
        ("pStrongSignPara", ctypes.c_void_p),  # PCCERT_STRONG_SIGN_PARA
        ("dwStrongSignFlags", _DWORD),
    )


# types of parameters of C functions used (required by pypy)

_crypt32.CertCreateCertificateContext.argtypes = [
    _DWORD,  # cert encoding
    ctypes.c_char_p,  # cert
    _DWORD,
]  # cert size
_crypt32.CertCreateCertificateContext.restype = _PCCERT_CONTEXT

_crypt32.CertGetCertificateChain.argtypes = [
    ctypes.c_void_p,  # HCERTCHAINENGINE
    _PCCERT_CONTEXT,
    ctypes.c_void_p,  # LPFILETIME
    ctypes.c_void_p,  # HCERTSTORE
    ctypes.c_void_p,  # PCERT_CHAIN_PARA
    _DWORD,
    ctypes.c_void_p,  # LPVOID
    ctypes.c_void_p,  # PCCERT_CHAIN_CONTEXT *
]
_crypt32.CertGetCertificateChain.restype = _BOOL

_crypt32.CertFreeCertificateContext.argtypes = [_PCCERT_CONTEXT]
_crypt32.CertFreeCertificateContext.restype = _BOOL

_kernel32.CreateFileA.argtypes = [
    _LPCSTR,
    _DWORD,
    _DWORD,
    ctypes.c_void_p,
    _DWORD,
    _DWORD,
    _HANDLE,
]
_kernel32.CreateFileA.restype = _HANDLE

_kernel32.GetFileInformationByHandle.argtypes = [_HANDLE, ctypes.c_void_p]
_kernel32.GetFileInformationByHandle.restype = _BOOL

_kernel32.CloseHandle.argtypes = [_HANDLE]
_kernel32.CloseHandle.restype = _BOOL

try:
    _kernel32.CreateHardLinkA.argtypes = [_LPCSTR, _LPCSTR, ctypes.c_void_p]
    _kernel32.CreateHardLinkA.restype = _BOOL
except AttributeError:
    pass

_kernel32.SetFileAttributesA.argtypes = [_LPCSTR, _DWORD]
_kernel32.SetFileAttributesA.restype = _BOOL

_DRIVE_UNKNOWN = 0
_DRIVE_NO_ROOT_DIR = 1
_DRIVE_REMOVABLE = 2
_DRIVE_FIXED = 3
_DRIVE_REMOTE = 4
_DRIVE_CDROM = 5
_DRIVE_RAMDISK = 6

_kernel32.GetDriveTypeA.argtypes = [_LPCSTR]
_kernel32.GetDriveTypeA.restype = _UINT

_kernel32.GetVolumeInformationA.argtypes = [
    _LPCSTR,
    ctypes.c_void_p,
    _DWORD,
    ctypes.c_void_p,
    ctypes.c_void_p,
    ctypes.c_void_p,
    ctypes.c_void_p,
    _DWORD,
]
_kernel32.GetVolumeInformationA.restype = _BOOL

_kernel32.GetVolumePathNameA.argtypes = [_LPCSTR, ctypes.c_void_p, _DWORD]
_kernel32.GetVolumePathNameA.restype = _BOOL

_kernel32.OpenProcess.argtypes = [_DWORD, _BOOL, _DWORD]
_kernel32.OpenProcess.restype = _HANDLE

_kernel32.GetExitCodeProcess.argtypes = [_HANDLE, ctypes.c_void_p]
_kernel32.GetExitCodeProcess.restype = _BOOL

_kernel32.GetLastError.argtypes = []
_kernel32.GetLastError.restype = _DWORD

_kernel32.GetModuleFileNameA.argtypes = [_HANDLE, ctypes.c_void_p, _DWORD]
_kernel32.GetModuleFileNameA.restype = _DWORD

_kernel32.CreateProcessA.argtypes = [
    _LPCSTR,
    _LPCSTR,
    ctypes.c_void_p,
    ctypes.c_void_p,
    _BOOL,
    _DWORD,
    ctypes.c_void_p,
    _LPCSTR,
    ctypes.c_void_p,
    ctypes.c_void_p,
]
_kernel32.CreateProcessA.restype = _BOOL

_kernel32.ExitProcess.argtypes = [_UINT]
_kernel32.ExitProcess.restype = None

_kernel32.GetCurrentProcessId.argtypes = []
_kernel32.GetCurrentProcessId.restype = _DWORD

# pytype: disable=module-attr
_SIGNAL_HANDLER = ctypes.WINFUNCTYPE(_BOOL, _DWORD)
# pytype: enable=module-attr
_kernel32.SetConsoleCtrlHandler.argtypes = [_SIGNAL_HANDLER, _BOOL]
_kernel32.SetConsoleCtrlHandler.restype = _BOOL

_kernel32.SetConsoleMode.argtypes = [_HANDLE, _DWORD]
_kernel32.SetConsoleMode.restype = _BOOL

_kernel32.GetConsoleMode.argtypes = [_HANDLE, ctypes.c_void_p]
_kernel32.GetConsoleMode.restype = _BOOL

_kernel32.GetStdHandle.argtypes = [_DWORD]
_kernel32.GetStdHandle.restype = _HANDLE

_kernel32.GetConsoleScreenBufferInfo.argtypes = [_HANDLE, ctypes.c_void_p]
_kernel32.GetConsoleScreenBufferInfo.restype = _BOOL

_advapi32.GetUserNameA.argtypes = [ctypes.c_void_p, ctypes.c_void_p]
_advapi32.GetUserNameA.restype = _BOOL

_user32.GetWindowThreadProcessId.argtypes = [_HANDLE, ctypes.c_void_p]
_user32.GetWindowThreadProcessId.restype = _DWORD

_user32.ShowWindow.argtypes = [_HANDLE, ctypes.c_int]
_user32.ShowWindow.restype = _BOOL

# pytype: disable=module-attr
_WNDENUMPROC = ctypes.WINFUNCTYPE(_BOOL, _HWND, _LPARAM)
# pytype: enable=module-attr
_user32.EnumWindows.argtypes = [_WNDENUMPROC, _LPARAM]
_user32.EnumWindows.restype = _BOOL

_kernel32.PeekNamedPipe.argtypes = [
    _HANDLE,
    ctypes.c_void_p,
    _DWORD,
    ctypes.c_void_p,
    ctypes.c_void_p,
    ctypes.c_void_p,
]
_kernel32.PeekNamedPipe.restype = _BOOL


def _raiseoserror(name: bytes) -> NoReturn:
    # Force the code to a signed int to avoid an 'int too large' error.
    # See https://bugs.python.org/issue28474
    code = _kernel32.GetLastError()
    if code > 0x7FFFFFFF:
        code -= 2 ** 32
    err = ctypes.WinError(code=code)  # pytype: disable=module-attr
    raise OSError(
        err.errno, '%s: %s' % (encoding.strfromlocal(name), err.strerror)
    )


def _getfileinfo(name: bytes) -> _BY_HANDLE_FILE_INFORMATION:
    fh = _kernel32.CreateFileA(
        name,
        0,
        _FILE_SHARE_READ | _FILE_SHARE_WRITE | _FILE_SHARE_DELETE,
        None,
        _OPEN_EXISTING,
        _FILE_FLAG_BACKUP_SEMANTICS,
        None,
    )
    if fh == _INVALID_HANDLE_VALUE:
        _raiseoserror(name)
    try:
        fi = _BY_HANDLE_FILE_INFORMATION()
        if not _kernel32.GetFileInformationByHandle(fh, ctypes.byref(fi)):
            _raiseoserror(name)
        return fi
    finally:
        _kernel32.CloseHandle(fh)


def checkcertificatechain(cert: bytes, build: bool = True) -> bool:
    """Tests the given certificate to see if there is a complete chain to a
    trusted root certificate.  As a side effect, missing certificates are
    downloaded and installed unless ``build=False``.  True is returned if a
    chain to a trusted root exists (even if built on the fly), otherwise
    False.  NB: A chain to a trusted root does NOT imply that the certificate
    is valid.
    """

    chainctxptr = ctypes.POINTER(CERT_CHAIN_CONTEXT)

    pchainctx = chainctxptr()
    chainpara = CERT_CHAIN_PARA(
        cbSize=ctypes.sizeof(CERT_CHAIN_PARA), RequestedUsage=CERT_USAGE_MATCH()
    )

    certctx = _crypt32.CertCreateCertificateContext(
        X509_ASN_ENCODING, cert, len(cert)
    )
    if certctx is None:
        _raiseoserror(b'CertCreateCertificateContext')

    flags = 0

    if not build:
        flags |= 0x100  # CERT_CHAIN_DISABLE_AUTH_ROOT_AUTO_UPDATE

    try:
        # Building the certificate chain will update root certs as necessary.
        if not _crypt32.CertGetCertificateChain(
            None,  # hChainEngine
            certctx,  # pCertContext
            None,  # pTime
            None,  # hAdditionalStore
            ctypes.byref(chainpara),
            flags,
            None,  # pvReserved
            ctypes.byref(pchainctx),
        ):
            _raiseoserror(b'CertGetCertificateChain')

        chainctx = pchainctx.contents

        return chainctx.dwErrorStatus & CERT_TRUST_IS_PARTIAL_CHAIN == 0
    finally:
        if pchainctx:
            _crypt32.CertFreeCertificateChain(pchainctx)
        _crypt32.CertFreeCertificateContext(certctx)


def oslink(src: bytes, dst: bytes) -> None:
    try:
        if not _kernel32.CreateHardLinkA(dst, src, None):
            _raiseoserror(src)
    except AttributeError:  # Wine doesn't support this function
        _raiseoserror(src)


def nlinks(name: bytes) -> int:
    '''return number of hardlinks for the given file'''
    return _getfileinfo(name).nNumberOfLinks


def samefile(path1: bytes, path2: bytes) -> bool:
    '''Returns whether path1 and path2 refer to the same file or directory.'''
    res1 = _getfileinfo(path1)
    res2 = _getfileinfo(path2)
    return (
        res1.dwVolumeSerialNumber == res2.dwVolumeSerialNumber
        and res1.nFileIndexHigh == res2.nFileIndexHigh
        and res1.nFileIndexLow == res2.nFileIndexLow
    )


def samedevice(path1: bytes, path2: bytes) -> bool:
    '''Returns whether path1 and path2 are on the same device.'''
    res1 = _getfileinfo(path1)
    res2 = _getfileinfo(path2)
    return res1.dwVolumeSerialNumber == res2.dwVolumeSerialNumber


def peekpipe(pipe) -> int:
    handle = msvcrt.get_osfhandle(pipe.fileno())  # pytype: disable=module-attr
    avail = _DWORD()

    if not _kernel32.PeekNamedPipe(
        handle, None, 0, None, ctypes.byref(avail), None
    ):
        err = _kernel32.GetLastError()
        if err == _ERROR_BROKEN_PIPE:
            return 0
        raise ctypes.WinError(err)  # pytype: disable=module-attr

    return avail.value


def lasterrorwaspipeerror(err) -> bool:
    if err.errno != errno.EINVAL:
        return False
    err = _kernel32.GetLastError()
    return err == _ERROR_BROKEN_PIPE or err == _ERROR_NO_DATA


def testpid(pid: int) -> bool:
    """return True if pid is still running or unable to
    determine, False otherwise"""
    h = _kernel32.OpenProcess(_PROCESS_QUERY_INFORMATION, False, pid)
    if h:
        try:
            status = _DWORD()
            if _kernel32.GetExitCodeProcess(h, ctypes.byref(status)):
                return status.value == _STILL_ACTIVE
        finally:
            _kernel32.CloseHandle(h)
    return _kernel32.GetLastError() != _ERROR_INVALID_PARAMETER


def executablepath() -> bytes:
    '''return full path of hg.exe'''
    size = 600
    buf = ctypes.create_string_buffer(size + 1)
    len = _kernel32.GetModuleFileNameA(None, ctypes.byref(buf), size)
    # pytype: disable=module-attr
    if len == 0:
        raise ctypes.WinError()  # Note: WinError is a function
    elif len == size:
        raise ctypes.WinError(_ERROR_INSUFFICIENT_BUFFER)
    # pytype: enable=module-attr
    return buf.value


def getvolumename(path: bytes) -> Optional[bytes]:
    """Get the mount point of the filesystem from a directory or file
    (best-effort)

    Returns None if we are unsure. Raises OSError on ENOENT, EPERM, etc.
    """
    # realpath() calls GetFullPathName()
    realpath = os.path.realpath(path)

    # allocate at least MAX_PATH long since GetVolumePathName('c:\\', buf, 4)
    # somehow fails on Windows XP
    size = max(len(realpath), _MAX_PATH) + 1
    buf = ctypes.create_string_buffer(size)

    if not _kernel32.GetVolumePathNameA(realpath, ctypes.byref(buf), size):
        # Note: WinError is a function
        raise ctypes.WinError()  # pytype: disable=module-attr

    return buf.value


def getfstype(path: bytes) -> Optional[bytes]:
    """Get the filesystem type name from a directory or file (best-effort)

    Returns None if we are unsure. Raises OSError on ENOENT, EPERM, etc.
    """
    volume = getvolumename(path)

    t = _kernel32.GetDriveTypeA(volume)

    if t == _DRIVE_REMOTE:
        return b'cifs'
    elif t not in (
        _DRIVE_REMOVABLE,
        _DRIVE_FIXED,
        _DRIVE_CDROM,
        _DRIVE_RAMDISK,
    ):
        return None

    size = _MAX_PATH + 1
    name = ctypes.create_string_buffer(size)

    if not _kernel32.GetVolumeInformationA(
        volume, None, 0, None, None, None, ctypes.byref(name), size
    ):
        # Note: WinError is a function
        raise ctypes.WinError()  # pytype: disable=module-attr

    return name.value


def getuser() -> bytes:
    '''return name of current user'''
    size = _DWORD(300)
    buf = ctypes.create_string_buffer(size.value + 1)
    if not _advapi32.GetUserNameA(ctypes.byref(buf), ctypes.byref(size)):
        raise ctypes.WinError()  # pytype: disable=module-attr
    return buf.value


_signalhandler: List[_SIGNAL_HANDLER] = []


def setsignalhandler() -> None:
    """Register a termination handler for console events including
    CTRL+C. python signal handlers do not work well with socket
    operations.
    """

    def handler(event):
        _kernel32.ExitProcess(1)

    if _signalhandler:
        return  # already registered
    h = _SIGNAL_HANDLER(handler)
    _signalhandler.append(h)  # needed to prevent garbage collection
    if not _kernel32.SetConsoleCtrlHandler(h, True):
        raise ctypes.WinError()  # pytype: disable=module-attr


def hidewindow() -> None:
    def callback(hwnd, pid):
        wpid = _DWORD()
        _user32.GetWindowThreadProcessId(hwnd, ctypes.byref(wpid))
        if pid == wpid.value:
            _user32.ShowWindow(hwnd, _SW_HIDE)
            return False  # stop enumerating windows
        return True

    pid = _kernel32.GetCurrentProcessId()
    _user32.EnumWindows(_WNDENUMPROC(callback), pid)


def termsize() -> Tuple[int, int]:
    # cmd.exe does not handle CR like a unix console, the CR is
    # counted in the line length. On 80 columns consoles, if 80
    # characters are written, the following CR won't apply on the
    # current line but on the new one. Keep room for it.
    width = 80 - 1
    height = 25
    # Query stderr to avoid problems with redirections
    screenbuf = _kernel32.GetStdHandle(
        _STD_ERROR_HANDLE
    )  # don't close the handle returned
    if screenbuf is None or screenbuf == _INVALID_HANDLE_VALUE:
        return width, height
    csbi = _CONSOLE_SCREEN_BUFFER_INFO()
    if not _kernel32.GetConsoleScreenBufferInfo(screenbuf, ctypes.byref(csbi)):
        return width, height
    width = csbi.srWindow.Right - csbi.srWindow.Left  # don't '+ 1'
    height = csbi.srWindow.Bottom - csbi.srWindow.Top + 1
    return width, height


def enablevtmode() -> bool:
    """Enable virtual terminal mode for the associated console.  Return True if
    enabled, else False."""

    ENABLE_VIRTUAL_TERMINAL_PROCESSING = 0x4

    handle = _kernel32.GetStdHandle(
        _STD_OUTPUT_HANDLE
    )  # don't close the handle
    if handle == _INVALID_HANDLE_VALUE:
        return False

    mode = _DWORD(0)

    if not _kernel32.GetConsoleMode(handle, ctypes.byref(mode)):
        return False

    if (mode.value & ENABLE_VIRTUAL_TERMINAL_PROCESSING) == 0:
        mode.value |= ENABLE_VIRTUAL_TERMINAL_PROCESSING

        if not _kernel32.SetConsoleMode(handle, mode):
            return False

    return True


def spawndetached(args: List[bytes]) -> int:
    # No standard library function really spawns a fully detached
    # process under win32 because they allocate pipes or other objects
    # to handle standard streams communications. Passing these objects
    # to the child process requires handle inheritance to be enabled
    # which makes really detached processes impossible.
    si = _STARTUPINFO()
    si.cb = ctypes.sizeof(_STARTUPINFO)

    pi = _PROCESS_INFORMATION()

    env = b''
    for k in encoding.environ:
        env += b"%s=%s\0" % (k, encoding.environ[k])
    if not env:
        env = b'\0'
    env += b'\0'

    args = subprocess.list2cmdline(pycompat.rapply(encoding.strfromlocal, args))

    # TODO: CreateProcessW on py3?
    res = _kernel32.CreateProcessA(
        None,
        encoding.strtolocal(args),
        None,
        None,
        False,
        _CREATE_NO_WINDOW,
        env,
        encoding.getcwd(),
        ctypes.byref(si),
        ctypes.byref(pi),
    )
    if not res:
        raise ctypes.WinError()  # pytype: disable=module-attr

    _kernel32.CloseHandle(pi.hProcess)
    _kernel32.CloseHandle(pi.hThread)

    return pi.dwProcessId


def unlink(f: bytes) -> None:
    '''try to implement POSIX' unlink semantics on Windows'''

    if os.path.isdir(f):
        # use EPERM because it is POSIX prescribed value, even though
        # unlink(2) on directories returns EISDIR on Linux
        raise IOError(
            errno.EPERM,
            r"Unlinking directory not permitted: '%s'"
            % encoding.strfromlocal(f),
        )

    # POSIX allows to unlink and rename open files. Windows has serious
    # problems with doing that:
    # - Calling os.unlink (or os.rename) on a file f fails if f or any
    #   hardlinked copy of f has been opened with Python's open(). There is no
    #   way such a file can be deleted or renamed on Windows (other than
    #   scheduling the delete or rename for the next reboot).
    # - Calling os.unlink on a file that has been opened with Mercurial's
    #   posixfile (or comparable methods) will delay the actual deletion of
    #   the file for as long as the file is held open. The filename is blocked
    #   during that time and cannot be used for recreating a new file under
    #   that same name ("zombie file"). Directories containing such zombie files
    #   cannot be removed or moved.
    # A file that has been opened with posixfile can be renamed, so we rename
    # f to a random temporary name before calling os.unlink on it. This allows
    # callers to recreate f immediately while having other readers do their
    # implicit zombie filename blocking on a temporary name.

    for tries in range(10):
        temp = b'%s-%08x' % (f, random.randint(0, 0xFFFFFFFF))
        try:
            os.rename(f, temp)
            break
        except FileExistsError:
            pass
    else:
        raise IOError(errno.EEXIST, "No usable temporary filename found")

    try:
        os.unlink(temp)
    except OSError:
        # The unlink might have failed because the READONLY attribute may heave
        # been set on the original file. Rename works fine with READONLY set,
        # but not os.unlink. Reset all attributes and try again.
        _kernel32.SetFileAttributesA(temp, _FILE_ATTRIBUTE_NORMAL)
        try:
            os.unlink(temp)
        except OSError:
            # The unlink might have failed due to some very rude AV-Scanners.
            # Leaking a tempfile is the lesser evil than aborting here and
            # leaving some potentially serious inconsistencies.
            pass


def makedir(path: bytes, notindexed: bool) -> None:
    os.mkdir(path)
    if notindexed:
        _kernel32.SetFileAttributesA(path, _FILE_ATTRIBUTE_NOT_CONTENT_INDEXED)