hgext/color.py

sslutil: prevent CRIME

ssl.create_default_context() disables compression on the TLS channel
in order to prevent CRIME. I think we should follow CPython's lead
and attempt to disable channel compression in order to help prevent
information leakage.

Sadly, I don't think there is anything we can do on Python versions
that don't have an SSLContext, as there is no way to set channel
options with the limited ssl API.

# color.py color output for Mercurial commands
#
# Copyright (C) 2007 Kevin Christen <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''colorize output from some commands

The color extension colorizes output from several Mercurial commands.
For example, the diff command shows additions in green and deletions
in red, while the status command shows modified files in magenta. Many
other commands have analogous colors. It is possible to customize
these colors.

Effects
-------

Other effects in addition to color, like bold and underlined text, are
also available. By default, the terminfo database is used to find the
terminal codes used to change color and effect.  If terminfo is not
available, then effects are rendered with the ECMA-48 SGR control
function (aka ANSI escape codes).

The available effects in terminfo mode are 'blink', 'bold', 'dim',
'inverse', 'invisible', 'italic', 'standout', and 'underline'; in
ECMA-48 mode, the options are 'bold', 'inverse', 'italic', and
'underline'.  How each is rendered depends on the terminal emulator.
Some may not be available for a given terminal type, and will be
silently ignored.

Labels
------

Text receives color effects depending on the labels that it has. Many
default Mercurial commands emit labelled text. You can also define
your own labels in templates using the label function, see :hg:`help
templates`. A single portion of text may have more than one label. In
that case, effects given to the last label will override any other
effects. This includes the special "none" effect, which nullifies
other effects.

Labels are normally invisible. In order to see these labels and their
position in the text, use the global --color=debug option. The same
anchor text may be associated to multiple labels, e.g.

  [log.changeset changeset.secret|changeset:   22611:6f0a53c8f587]

The following are the default effects for some default labels. Default
effects may be overridden from your configuration file::

  [color]
  status.modified = blue bold underline red_background
  status.added = green bold
  status.removed = red bold blue_background
  status.deleted = cyan bold underline
  status.unknown = magenta bold underline
  status.ignored = black bold

  # 'none' turns off all effects
  status.clean = none
  status.copied = none

  qseries.applied = blue bold underline
  qseries.unapplied = black bold
  qseries.missing = red bold

  diff.diffline = bold
  diff.extended = cyan bold
  diff.file_a = red bold
  diff.file_b = green bold
  diff.hunk = magenta
  diff.deleted = red
  diff.inserted = green
  diff.changed = white
  diff.tab =
  diff.trailingwhitespace = bold red_background

  # Blank so it inherits the style of the surrounding label
  changeset.public =
  changeset.draft =
  changeset.secret =

  resolve.unresolved = red bold
  resolve.resolved = green bold

  bookmarks.active = green

  branches.active = none
  branches.closed = black bold
  branches.current = green
  branches.inactive = none

  tags.normal = green
  tags.local = black bold

  rebase.rebased = blue
  rebase.remaining = red bold

  shelve.age = cyan
  shelve.newest = green bold
  shelve.name = blue bold

  histedit.remaining = red bold

Custom colors
-------------

Because there are only eight standard colors, this module allows you
to define color names for other color slots which might be available
for your terminal type, assuming terminfo mode.  For instance::

  color.brightblue = 12
  color.pink = 207
  color.orange = 202

to set 'brightblue' to color slot 12 (useful for 16 color terminals
that have brighter colors defined in the upper eight) and, 'pink' and
'orange' to colors in 256-color xterm's default color cube.  These
defined colors may then be used as any of the pre-defined eight,
including appending '_background' to set the background to that color.

Modes
-----

By default, the color extension will use ANSI mode (or win32 mode on
Windows) if it detects a terminal. To override auto mode (to enable
terminfo mode, for example), set the following configuration option::

  [color]
  mode = terminfo

Any value other than 'ansi', 'win32', 'terminfo', or 'auto' will
disable color.

Note that on some systems, terminfo mode may cause problems when using
color with the pager extension and less -R. less with the -R option
will only display ECMA-48 color codes, and terminfo mode may sometimes
emit codes that less doesn't understand. You can work around this by
either using ansi mode (or auto mode), or by using less -r (which will
pass through all terminal control codes, not just color control
codes).

On some systems (such as MSYS in Windows), the terminal may support
a different color mode than the pager (activated via the "pager"
extension). It is possible to define separate modes depending on whether
the pager is active::

  [color]
  mode = auto
  pagermode = ansi

If ``pagermode`` is not defined, the ``mode`` will be used.
'''

from __future__ import absolute_import

import os

from mercurial.i18n import _
from mercurial import (
    cmdutil,
    commands,
    dispatch,
    extensions,
    subrepo,
    ui as uimod,
    util,
)

cmdtable = {}
command = cmdutil.command(cmdtable)
# Note for extension authors: ONLY specify testedwith = 'internal' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'internal'

# start and stop parameters for effects
_effects = {'none': 0, 'black': 30, 'red': 31, 'green': 32, 'yellow': 33,
            'blue': 34, 'magenta': 35, 'cyan': 36, 'white': 37, 'bold': 1,
            'italic': 3, 'underline': 4, 'inverse': 7, 'dim': 2,
            'black_background': 40, 'red_background': 41,
            'green_background': 42, 'yellow_background': 43,
            'blue_background': 44, 'purple_background': 45,
            'cyan_background': 46, 'white_background': 47}

def _terminfosetup(ui, mode):
    '''Initialize terminfo data and the terminal if we're in terminfo mode.'''

    global _terminfo_params
    # If we failed to load curses, we go ahead and return.
    if not _terminfo_params:
        return
    # Otherwise, see what the config file says.
    if mode not in ('auto', 'terminfo'):
        return

    _terminfo_params.update((key[6:], (False, int(val)))
        for key, val in ui.configitems('color')
        if key.startswith('color.'))

    try:
        curses.setupterm()
    except curses.error as e:
        _terminfo_params = {}
        return

    for key, (b, e) in _terminfo_params.items():
        if not b:
            continue
        if not curses.tigetstr(e):
            # Most terminals don't support dim, invis, etc, so don't be
            # noisy and use ui.debug().
            ui.debug("no terminfo entry for %s\n" % e)
            del _terminfo_params[key]
    if not curses.tigetstr('setaf') or not curses.tigetstr('setab'):
        # Only warn about missing terminfo entries if we explicitly asked for
        # terminfo mode.
        if mode == "terminfo":
            ui.warn(_("no terminfo entry for setab/setaf: reverting to "
              "ECMA-48 color\n"))
        _terminfo_params = {}

def _modesetup(ui, coloropt):
    global _terminfo_params

    if coloropt == 'debug':
        return 'debug'

    auto = (coloropt == 'auto')
    always = not auto and util.parsebool(coloropt)
    if not always and not auto:
        return None

    formatted = always or (os.environ.get('TERM') != 'dumb' and ui.formatted())

    mode = ui.config('color', 'mode', 'auto')

    # If pager is active, color.pagermode overrides color.mode.
    if getattr(ui, 'pageractive', False):
        mode = ui.config('color', 'pagermode', mode)

    realmode = mode
    if mode == 'auto':
        if os.name == 'nt':
            term = os.environ.get('TERM')
            # TERM won't be defined in a vanilla cmd.exe environment.

            # UNIX-like environments on Windows such as Cygwin and MSYS will
            # set TERM. They appear to make a best effort attempt at setting it
            # to something appropriate. However, not all environments with TERM
            # defined support ANSI. Since "ansi" could result in terminal
            # gibberish, we error on the side of selecting "win32". However, if
            # w32effects is not defined, we almost certainly don't support
            # "win32", so don't even try.
            if (term and 'xterm' in term) or not w32effects:
                realmode = 'ansi'
            else:
                realmode = 'win32'
        else:
            realmode = 'ansi'

    def modewarn():
        # only warn if color.mode was explicitly set and we're in
        # an interactive terminal
        if mode == realmode and ui.interactive():
            ui.warn(_('warning: failed to set color mode to %s\n') % mode)

    if realmode == 'win32':
        _terminfo_params = {}
        if not w32effects:
            modewarn()
            return None
        _effects.update(w32effects)
    elif realmode == 'ansi':
        _terminfo_params = {}
    elif realmode == 'terminfo':
        _terminfosetup(ui, mode)
        if not _terminfo_params:
            ## FIXME Shouldn't we return None in this case too?
            modewarn()
            realmode = 'ansi'
    else:
        return None

    if always or (auto and formatted):
        return realmode
    return None

try:
    import curses
    # Mapping from effect name to terminfo attribute name or color number.
    # This will also force-load the curses module.
    _terminfo_params = {'none': (True, 'sgr0'),
                        'standout': (True, 'smso'),
                        'underline': (True, 'smul'),
                        'reverse': (True, 'rev'),
                        'inverse': (True, 'rev'),
                        'blink': (True, 'blink'),
                        'dim': (True, 'dim'),
                        'bold': (True, 'bold'),
                        'invisible': (True, 'invis'),
                        'italic': (True, 'sitm'),
                        'black': (False, curses.COLOR_BLACK),
                        'red': (False, curses.COLOR_RED),
                        'green': (False, curses.COLOR_GREEN),
                        'yellow': (False, curses.COLOR_YELLOW),
                        'blue': (False, curses.COLOR_BLUE),
                        'magenta': (False, curses.COLOR_MAGENTA),
                        'cyan': (False, curses.COLOR_CYAN),
                        'white': (False, curses.COLOR_WHITE)}
except ImportError:
    _terminfo_params = {}

_styles = {'grep.match': 'red bold',
           'grep.linenumber': 'green',
           'grep.rev': 'green',
           'grep.change': 'green',
           'grep.sep': 'cyan',
           'grep.filename': 'magenta',
           'grep.user': 'magenta',
           'grep.date': 'magenta',
           'bookmarks.active': 'green',
           'branches.active': 'none',
           'branches.closed': 'black bold',
           'branches.current': 'green',
           'branches.inactive': 'none',
           'diff.changed': 'white',
           'diff.deleted': 'red',
           'diff.diffline': 'bold',
           'diff.extended': 'cyan bold',
           'diff.file_a': 'red bold',
           'diff.file_b': 'green bold',
           'diff.hunk': 'magenta',
           'diff.inserted': 'green',
           'diff.tab': '',
           'diff.trailingwhitespace': 'bold red_background',
           'changeset.public' : '',
           'changeset.draft' : '',
           'changeset.secret' : '',
           'diffstat.deleted': 'red',
           'diffstat.inserted': 'green',
           'histedit.remaining': 'red bold',
           'ui.prompt': 'yellow',
           'log.changeset': 'yellow',
           'patchbomb.finalsummary': '',
           'patchbomb.from': 'magenta',
           'patchbomb.to': 'cyan',
           'patchbomb.subject': 'green',
           'patchbomb.diffstats': '',
           'rebase.rebased': 'blue',
           'rebase.remaining': 'red bold',
           'resolve.resolved': 'green bold',
           'resolve.unresolved': 'red bold',
           'shelve.age': 'cyan',
           'shelve.newest': 'green bold',
           'shelve.name': 'blue bold',
           'status.added': 'green bold',
           'status.clean': 'none',
           'status.copied': 'none',
           'status.deleted': 'cyan bold underline',
           'status.ignored': 'black bold',
           'status.modified': 'blue bold',
           'status.removed': 'red bold',
           'status.unknown': 'magenta bold underline',
           'tags.normal': 'green',
           'tags.local': 'black bold'}


def _effect_str(effect):
    '''Helper function for render_effects().'''

    bg = False
    if effect.endswith('_background'):
        bg = True
        effect = effect[:-11]
    attr, val = _terminfo_params[effect]
    if attr:
        return curses.tigetstr(val)
    elif bg:
        return curses.tparm(curses.tigetstr('setab'), val)
    else:
        return curses.tparm(curses.tigetstr('setaf'), val)

def render_effects(text, effects):
    'Wrap text in commands to turn on each effect.'
    if not text:
        return text
    if not _terminfo_params:
        start = [str(_effects[e]) for e in ['none'] + effects.split()]
        start = '\033[' + ';'.join(start) + 'm'
        stop = '\033[' + str(_effects['none']) + 'm'
    else:
        start = ''.join(_effect_str(effect)
                        for effect in ['none'] + effects.split())
        stop = _effect_str('none')
    return ''.join([start, text, stop])

def extstyles():
    for name, ext in extensions.extensions():
        _styles.update(getattr(ext, 'colortable', {}))

def valideffect(effect):
    'Determine if the effect is valid or not.'
    good = False
    if not _terminfo_params and effect in _effects:
        good = True
    elif effect in _terminfo_params or effect[:-11] in _terminfo_params:
        good = True
    return good

def configstyles(ui):
    for status, cfgeffects in ui.configitems('color'):
        if '.' not in status or status.startswith('color.'):
            continue
        cfgeffects = ui.configlist('color', status)
        if cfgeffects:
            good = []
            for e in cfgeffects:
                if valideffect(e):
                    good.append(e)
                else:
                    ui.warn(_("ignoring unknown color/effect %r "
                              "(configured in color.%s)\n")
                            % (e, status))
            _styles[status] = ' '.join(good)

class colorui(uimod.ui):
    _colormode = 'ansi'
    def write(self, *args, **opts):
        if self._colormode is None:
            return super(colorui, self).write(*args, **opts)

        label = opts.get('label', '')
        if self._buffers and not opts.get('prompt', False):
            if self._bufferapplylabels:
                self._buffers[-1].extend(self.label(a, label) for a in args)
            else:
                self._buffers[-1].extend(args)
        elif self._colormode == 'win32':
            for a in args:
                win32print(a, super(colorui, self).write, **opts)
        else:
            return super(colorui, self).write(
                *[self.label(a, label) for a in args], **opts)

    def write_err(self, *args, **opts):
        if self._colormode is None:
            return super(colorui, self).write_err(*args, **opts)

        label = opts.get('label', '')
        if self._bufferstates and self._bufferstates[-1][0]:
            return self.write(*args, **opts)
        if self._colormode == 'win32':
            for a in args:
                win32print(a, super(colorui, self).write_err, **opts)
        else:
            return super(colorui, self).write_err(
                *[self.label(a, label) for a in args], **opts)

    def showlabel(self, msg, label):
        if label and msg:
            if msg[-1] == '\n':
                return "[%s|%s]\n" % (label, msg[:-1])
            else:
                return "[%s|%s]" % (label, msg)
        else:
            return msg

    def label(self, msg, label):
        if self._colormode is None:
            return super(colorui, self).label(msg, label)

        if self._colormode == 'debug':
            return self.showlabel(msg, label)

        effects = []
        for l in label.split():
            s = _styles.get(l, '')
            if s:
                effects.append(s)
            elif valideffect(l):
                effects.append(l)
        effects = ' '.join(effects)
        if effects:
            return '\n'.join([render_effects(s, effects)
                              for s in msg.split('\n')])
        return msg

def uisetup(ui):
    if ui.plain():
        return
    if not isinstance(ui, colorui):
        colorui.__bases__ = (ui.__class__,)
        ui.__class__ = colorui
    def colorcmd(orig, ui_, opts, cmd, cmdfunc):
        mode = _modesetup(ui_, opts['color'])
        colorui._colormode = mode
        if mode and mode != 'debug':
            extstyles()
            configstyles(ui_)
        return orig(ui_, opts, cmd, cmdfunc)
    def colorgit(orig, gitsub, commands, env=None, stream=False, cwd=None):
        if gitsub.ui._colormode and len(commands) and commands[0] == "diff":
                # insert the argument in the front,
                # the end of git diff arguments is used for paths
                commands.insert(1, '--color')
        return orig(gitsub, commands, env, stream, cwd)
    extensions.wrapfunction(dispatch, '_runcommand', colorcmd)
    extensions.wrapfunction(subrepo.gitsubrepo, '_gitnodir', colorgit)

def extsetup(ui):
    commands.globalopts.append(
        ('', 'color', 'auto',
         # i18n: 'always', 'auto', 'never', and 'debug' are keywords
         # and should not be translated
         _("when to colorize (boolean, always, auto, never, or debug)"),
         _('TYPE')))

@command('debugcolor', [], 'hg debugcolor')
def debugcolor(ui, repo, **opts):
    global _styles
    _styles = {}
    for effect in _effects.keys():
        _styles[effect] = effect
    ui.write(('color mode: %s\n') % ui._colormode)
    ui.write(_('available colors:\n'))
    for label, colors in _styles.items():
        ui.write(('%s\n') % colors, label=label)

if os.name != 'nt':
    w32effects = None
else:
    import ctypes
    import re

    _kernel32 = ctypes.windll.kernel32

    _WORD = ctypes.c_ushort

    _INVALID_HANDLE_VALUE = -1

    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 = 0xfffffff5L # (DWORD)-11
    _STD_ERROR_HANDLE = 0xfffffff4L  # (DWORD)-12

    _FOREGROUND_BLUE = 0x0001
    _FOREGROUND_GREEN = 0x0002
    _FOREGROUND_RED = 0x0004
    _FOREGROUND_INTENSITY = 0x0008

    _BACKGROUND_BLUE = 0x0010
    _BACKGROUND_GREEN = 0x0020
    _BACKGROUND_RED = 0x0040
    _BACKGROUND_INTENSITY = 0x0080

    _COMMON_LVB_REVERSE_VIDEO = 0x4000
    _COMMON_LVB_UNDERSCORE = 0x8000

    # http://msdn.microsoft.com/en-us/library/ms682088%28VS.85%29.aspx
    w32effects = {
        'none': -1,
        'black': 0,
        'red': _FOREGROUND_RED,
        'green': _FOREGROUND_GREEN,
        'yellow': _FOREGROUND_RED | _FOREGROUND_GREEN,
        'blue': _FOREGROUND_BLUE,
        'magenta': _FOREGROUND_BLUE | _FOREGROUND_RED,
        'cyan': _FOREGROUND_BLUE | _FOREGROUND_GREEN,
        'white': _FOREGROUND_RED | _FOREGROUND_GREEN | _FOREGROUND_BLUE,
        'bold': _FOREGROUND_INTENSITY,
        'black_background': 0x100,                  # unused value > 0x0f
        'red_background': _BACKGROUND_RED,
        'green_background': _BACKGROUND_GREEN,
        'yellow_background': _BACKGROUND_RED | _BACKGROUND_GREEN,
        'blue_background': _BACKGROUND_BLUE,
        'purple_background': _BACKGROUND_BLUE | _BACKGROUND_RED,
        'cyan_background': _BACKGROUND_BLUE | _BACKGROUND_GREEN,
        'white_background': (_BACKGROUND_RED | _BACKGROUND_GREEN |
                             _BACKGROUND_BLUE),
        'bold_background': _BACKGROUND_INTENSITY,
        'underline': _COMMON_LVB_UNDERSCORE,  # double-byte charsets only
        'inverse': _COMMON_LVB_REVERSE_VIDEO, # double-byte charsets only
    }

    passthrough = set([_FOREGROUND_INTENSITY,
                       _BACKGROUND_INTENSITY,
                       _COMMON_LVB_UNDERSCORE,
                       _COMMON_LVB_REVERSE_VIDEO])

    stdout = _kernel32.GetStdHandle(
                  _STD_OUTPUT_HANDLE)  # don't close the handle returned
    if stdout is None or stdout == _INVALID_HANDLE_VALUE:
        w32effects = None
    else:
        csbi = _CONSOLE_SCREEN_BUFFER_INFO()
        if not _kernel32.GetConsoleScreenBufferInfo(
                    stdout, ctypes.byref(csbi)):
            # stdout may not support GetConsoleScreenBufferInfo()
            # when called from subprocess or redirected
            w32effects = None
        else:
            origattr = csbi.wAttributes
            ansire = re.compile('\033\[([^m]*)m([^\033]*)(.*)',
                                re.MULTILINE | re.DOTALL)

    def win32print(text, orig, **opts):
        label = opts.get('label', '')
        attr = origattr

        def mapcolor(val, attr):
            if val == -1:
                return origattr
            elif val in passthrough:
                return attr | val
            elif val > 0x0f:
                return (val & 0x70) | (attr & 0x8f)
            else:
                return (val & 0x07) | (attr & 0xf8)

        # determine console attributes based on labels
        for l in label.split():
            style = _styles.get(l, '')
            for effect in style.split():
                try:
                    attr = mapcolor(w32effects[effect], attr)
                except KeyError:
                    # w32effects could not have certain attributes so we skip
                    # them if not found
                    pass
        # hack to ensure regexp finds data
        if not text.startswith('\033['):
            text = '\033[m' + text

        # Look for ANSI-like codes embedded in text
        m = re.match(ansire, text)

        try:
            while m:
                for sattr in m.group(1).split(';'):
                    if sattr:
                        attr = mapcolor(int(sattr), attr)
                _kernel32.SetConsoleTextAttribute(stdout, attr)
                orig(m.group(2), **opts)
                m = re.match(ansire, m.group(3))
        finally:
            # Explicitly reset original attributes
            _kernel32.SetConsoleTextAttribute(stdout, origattr)