# windows.py - Windows utility function implementations for Mercurial

#

#  Copyright 2005-2009 Matt Mackall <mpm@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.

from __future__ import absolute_import

import errno

import msvcrt

import os

import re

import stat

import sys

from .i18n import _

from . import (

    encoding,

    error,

    policy,

    pycompat,

    win32,

)

try:

    import _winreg as winreg

    winreg.CloseKey

except ImportError:

    import winreg

osutil = policy.importmod(r'osutil')

executablepath = win32.executablepath

getfsmountpoint = win32.getvolumename

getfstype = win32.getfstype

getuser = win32.getuser

hidewindow = win32.hidewindow

makedir = win32.makedir

nlinks = win32.nlinks

oslink = win32.oslink

samedevice = win32.samedevice

samefile = win32.samefile

setsignalhandler = win32.setsignalhandler

spawndetached = win32.spawndetached

split = os.path.split

testpid = win32.testpid

unlink = win32.unlink

umask = 0o022

class mixedfilemodewrapper(object):

    """Wraps a file handle when it is opened in read/write mode.

    fopen() and fdopen() on Windows have a specific-to-Windows requirement

    that files opened with mode r+, w+, or a+ make a call to a file positioning

    function when switching between reads and writes. Without this extra call,

    Python will raise a not very intuitive "IOError: [Errno 0] Error."

    This class wraps posixfile instances when the file is opened in read/write

    mode and automatically adds checks or inserts appropriate file positioning

    calls when necessary.

    """

    OPNONE = 0

    OPREAD = 1

    OPWRITE = 2

    def __init__(self, fp):

        object.__setattr__(self, r'_fp', fp)

        object.__setattr__(self, r'_lastop', 0)

    def __enter__(self):

        return self._fp.__enter__()

    def __exit__(self, exc_type, exc_val, exc_tb):

        self._fp.__exit__(exc_type, exc_val, exc_tb)

    def __getattr__(self, name):

        return getattr(self._fp, name)

    def __setattr__(self, name, value):

        return self._fp.__setattr__(name, value)

    def _noopseek(self):

        self._fp.seek(0, os.SEEK_CUR)

    def seek(self, *args, **kwargs):

        object.__setattr__(self, r'_lastop', self.OPNONE)

        return self._fp.seek(*args, **kwargs)

    def write(self, d):

        if self._lastop == self.OPREAD:

            self._noopseek()

        object.__setattr__(self, r'_lastop', self.OPWRITE)

        return self._fp.write(d)

    def writelines(self, *args, **kwargs):

        if self._lastop == self.OPREAD:

            self._noopeseek()

        object.__setattr__(self, r'_lastop', self.OPWRITE)

        return self._fp.writelines(*args, **kwargs)

    def read(self, *args, **kwargs):

        if self._lastop == self.OPWRITE:

            self._noopseek()

        object.__setattr__(self, r'_lastop', self.OPREAD)

        return self._fp.read(*args, **kwargs)

    def readline(self, *args, **kwargs):

        if self._lastop == self.OPWRITE:

            self._noopseek()

        object.__setattr__(self, r'_lastop', self.OPREAD)

        return self._fp.readline(*args, **kwargs)

    def readlines(self, *args, **kwargs):

        if self._lastop == self.OPWRITE:

            self._noopseek()

        object.__setattr__(self, r'_lastop', self.OPREAD)

        return self._fp.readlines(*args, **kwargs)

def posixfile(name, mode='r', buffering=-1):

    '''Open a file with even more POSIX-like semantics'''

    try:

        fp = osutil.posixfile(name, mode, buffering) # may raise WindowsError

        # The position when opening in append mode is implementation defined, so

        # make it consistent with other platforms, which position at EOF.

        if 'a' in mode:

            fp.seek(0, os.SEEK_END)

        if '+' in mode:

            return mixedfilemodewrapper(fp)

        return fp

    except WindowsError as err:

        # convert to a friendlier exception

        raise IOError(err.errno, '%s: %s' % (

            name, encoding.strtolocal(err.strerror)))

# may be wrapped by win32mbcs extension

listdir = osutil.listdir

class winstdout(object):

    '''stdout on windows misbehaves if sent through a pipe'''

    def __init__(self, fp):

        self.fp = fp

    def __getattr__(self, key):

        return getattr(self.fp, key)

    def close(self):

        try:

            self.fp.close()

        except IOError:

            pass

    def write(self, s):

        try:

            # This is workaround for "Not enough space" error on

            # writing large size of data to console.

            limit = 16000

            l = len(s)

            start = 0

            self.softspace = 0

            while start < l:

                end = start + limit

                self.fp.write(s[start:end])

                start = end

        except IOError as inst:

            if inst.errno != 0:

                raise

            self.close()

            raise IOError(errno.EPIPE, 'Broken pipe')

    def flush(self):

        try:

            return self.fp.flush()

        except IOError as inst:

            if inst.errno != errno.EINVAL:

                raise

            raise IOError(errno.EPIPE, 'Broken pipe')

def _is_win_9x():

    '''return true if run on windows 95, 98 or me.'''

    try:

        return sys.getwindowsversion()[3] == 1

    except AttributeError:

        return 'command' in encoding.environ.get('comspec', '')

def openhardlinks():

    return not _is_win_9x()

def parsepatchoutput(output_line):

    """parses the output produced by patch and returns the filename"""

    pf = output_line[14:]

    if pf[0] == '`':

        pf = pf[1:-1] # Remove the quotes

    return pf

def sshargs(sshcmd, host, user, port):

    '''Build argument list for ssh or Plink'''

    pflag = 'plink' in sshcmd.lower() and '-P' or '-p'

    args = user and ("%s@%s" % (user, host)) or host

    if args.startswith('-') or args.startswith('/'):

        raise error.Abort(

            _('illegal ssh hostname or username starting with - or /: %s') %

            args)

    args = shellquote(args)

    if port:

        args = '%s %s %s' % (pflag, shellquote(port), args)

    return args

def setflags(f, l, x):

    pass

def copymode(src, dst, mode=None):

    pass

def checkexec(path):

    return False

def checklink(path):

    return False

def setbinary(fd):

    # When run without console, pipes may expose invalid

    # fileno(), usually set to -1.

    fno = getattr(fd, 'fileno', None)

    if fno is not None and fno() >= 0:

        msvcrt.setmode(fno(), os.O_BINARY)

def pconvert(path):

    return path.replace(pycompat.ossep, '/')

def localpath(path):

    return path.replace('/', '\\')

def normpath(path):

    return pconvert(os.path.normpath(path))

def normcase(path):

    return encoding.upper(path) # NTFS compares via upper()

# see posix.py for definitions

normcasespec = encoding.normcasespecs.upper

normcasefallback = encoding.upperfallback

def samestat(s1, s2):

    return False

# A sequence of backslashes is special iff it precedes a double quote:

# - if there's an even number of backslashes, the double quote is not

#   quoted (i.e. it ends the quoted region)

# - if there's an odd number of backslashes, the double quote is quoted

# - in both cases, every pair of backslashes is unquoted into a single

#   backslash

# (See http://msdn2.microsoft.com/en-us/library/a1y7w461.aspx )

# So, to quote a string, we must surround it in double quotes, double

# the number of backslashes that precede double quotes and add another

# backslash before every double quote (being careful with the double

# quote we've appended to the end)

_quotere = None

_needsshellquote = None

def shellquote(s):

    r"""

    >>> shellquote(br'C:\Users\xyz')

    '"C:\\Users\\xyz"'

    >>> shellquote(br'C:\Users\xyz/mixed')

    '"C:\\Users\\xyz/mixed"'

    >>> # Would be safe not to quote too, since it is all double backslashes

    >>> shellquote(br'C:\\Users\\xyz')

    '"C:\\\\Users\\\\xyz"'

    >>> # But this must be quoted

    >>> shellquote(br'C:\\Users\\xyz/abc')

    '"C:\\\\Users\\\\xyz/abc"'

    """

    global _quotere

    if _quotere is None:

        _quotere = re.compile(r'(\\*)("|\\$)')

    global _needsshellquote

    if _needsshellquote is None:

        # ":" is also treated as "safe character", because it is used as a part

        # of path name on Windows.  "\" is also part of a path name, but isn't

        # safe because shlex.split() (kind of) treats it as an escape char and

        # drops it.  It will leave the next character, even if it is another

        # "\".

        _needsshellquote = re.compile(r'[^a-zA-Z0-9._:/-]').search

    if s and not _needsshellquote(s) and not _quotere.search(s):

        # "s" shouldn't have to be quoted

        return s

    return '"%s"' % _quotere.sub(r'\1\1\\\2', s)

def quotecommand(cmd):

    """Build a command string suitable for os.popen* calls."""

    if sys.version_info < (2, 7, 1):

        # Python versions since 2.7.1 do this extra quoting themselves

        return '"' + cmd + '"'

    return cmd

def popen(command, mode='r'):

    # Work around "popen spawned process may not write to stdout

    # under windows"

    # http://bugs.python.org/issue1366

    command += " 2> %s" % os.devnull

    return os.popen(quotecommand(command), mode)

def explainexit(code):

    return _("exited with status %d") % code, code

# if you change this stub into a real check, please try to implement the

# username and groupname functions above, too.

def isowner(st):

    return True

def findexe(command):

    '''Find executable for command searching like cmd.exe does.

    If command is a basename then PATH is searched for command.

    PATH isn't searched if command is an absolute or relative path.

    An extension from PATHEXT is found and added if not present.

    If command isn't found None is returned.'''

    pathext = encoding.environ.get('PATHEXT', '.COM;.EXE;.BAT;.CMD')

    pathexts = [ext for ext in pathext.lower().split(pycompat.ospathsep)]

    if os.path.splitext(command)[1].lower() in pathexts:

        pathexts = ['']

    def findexisting(pathcommand):

        'Will append extension (if needed) and return existing file'

        for ext in pathexts:

            executable = pathcommand + ext

            if os.path.exists(executable):

                return executable

        return None

    if pycompat.ossep in command:

        return findexisting(command)

    for path in encoding.environ.get('PATH', '').split(pycompat.ospathsep):

        executable = findexisting(os.path.join(path, command))

        if executable is not None:

            return executable

    return findexisting(os.path.expanduser(os.path.expandvars(command)))

_wantedkinds = {stat.S_IFREG, stat.S_IFLNK}

def statfiles(files):

    '''Stat each file in files. Yield each stat, or None if a file

    does not exist or has a type we don't care about.

    Cluster and cache stat per directory to minimize number of OS stat calls.'''

    dircache = {} # dirname -> filename -> status | None if file does not exist

    getkind = stat.S_IFMT

    for nf in files:

        nf  = normcase(nf)

        dir, base = os.path.split(nf)

        if not dir:

            dir = '.'

        cache = dircache.get(dir, None)

        if cache is None:

            try:

                dmap = dict([(normcase(n), s)

                             for n, k, s in listdir(dir, True)

                             if getkind(s.st_mode) in _wantedkinds])

            except OSError as err:

                # Python >= 2.5 returns ENOENT and adds winerror field

                # EINVAL is raised if dir is not a directory.

                if err.errno not in (errno.ENOENT, errno.EINVAL,

                                     errno.ENOTDIR):

                    raise

                dmap = {}

            cache = dircache.setdefault(dir, dmap)

        yield cache.get(base, None)

def username(uid=None):

    """Return the name of the user with the given uid.

    If uid is None, return the name of the current user."""

    return None

def groupname(gid=None):

    """Return the name of the group with the given gid.

    If gid is None, return the name of the current group."""

    return None