view mercurial/color.py @ 49000:dd6b67d5c256 stable

rust: fix unsound `OwningDirstateMap`

As per the previous patch, `OwningDirstateMap` is unsound. Self-referential
structs are difficult to implement correctly in Rust since the compiler is
free to move structs around as much as it wants to. They are also very rarely
needed in practice, so the state-of-the-art on how they should be done within
the Rust rules is still a bit new.

The crate `ouroboros` is an attempt at providing a safe way (in the Rust sense)
of declaring self-referential structs. It is getting a lot attention and was
improved very quickly when soundness issues were found in the past: rather than
relying on our own (limited) review circle, we might as well use the de-facto
common crate to fix this problem. This will give us a much better chance of
finding issues should any new ones be discovered as well as the benefit of
fewer `unsafe` APIs of our own.

I was starting to think about how I would present a safe API to the old struct
but soon realized that the callback-based approach was already done in
`ouroboros`, along with a lot more care towards refusing incorrect structs.

In short: we don't return a mutable reference to the `DirstateMap` anymore, we
expect users of its API to pass a `FnOnce` that takes the map as an argument.
This allows our `OwningDirstateMap` to control the input and output lifetimes
of the code that modifies it to prevent such issues.

Changing to `ouroboros` meant changing every API with it, but it is relatively
low churn in the end. It correctly identified the example buggy modification of
`copy_map_insert` outlined in the previous patch as violating the borrow rules.

Differential Revision: https://phab.mercurial-scm.org/D12429

# utility for color output for Mercurial commands
#
# Copyright (C) 2007 Kevin Christen <[e-mail]> and other
#
# 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 re

from .i18n import _
from .pycompat import getattr

from . import (
    encoding,
    pycompat,
)

from .utils import stringutil

try:
    import curses

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

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

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


def loadcolortable(ui, extname, colortable):
    _defaultstyles.update(colortable)


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

    # If we failed to load curses, we go ahead and return.
    if curses is None:
        return
    # Otherwise, see what the config file says.
    if mode not in (b'auto', b'terminfo'):
        return
    ui._terminfoparams.update(_baseterminfoparams)

    for key, val in ui.configitems(b'color'):
        if key.startswith(b'color.'):
            newval = (False, int(val), b'')
            ui._terminfoparams[key[6:]] = newval
        elif key.startswith(b'terminfo.'):
            newval = (True, b'', val.replace(b'\\E', b'\x1b'))
            ui._terminfoparams[key[9:]] = newval
    try:
        curses.setupterm()
    except curses.error:
        ui._terminfoparams.clear()
        return

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


def setup(ui):
    """configure color on a ui

    That function both set the colormode for the ui object and read
    the configuration looking for custom colors and effect definitions."""
    mode = _modesetup(ui)
    ui._colormode = mode
    if mode and mode != b'debug':
        configstyles(ui)


def _modesetup(ui):
    if ui.plain(b'color'):
        return None
    config = ui.config(b'ui', b'color')
    if config == b'debug':
        return b'debug'

    auto = config == b'auto'
    always = False
    if not auto and stringutil.parsebool(config):
        # We want the config to behave like a boolean, "on" is actually auto,
        # but "always" value is treated as a special case to reduce confusion.
        if (
            ui.configsource(b'ui', b'color') == b'--color'
            or config == b'always'
        ):
            always = True
        else:
            auto = True

    if not always and not auto:
        return None

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

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

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

    realmode = mode
    if pycompat.iswindows:
        from . import win32

        if mode == b'auto':
            # 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.
            # w32effects is not populated when stdout is redirected, so checking
            # it first avoids win32 calls in a state known to error out.
            if not w32effects or win32.enablevtmode():
                realmode = b'ansi'
            else:
                realmode = b'win32'
        # An empty w32effects is a clue that stdout is redirected, and thus
        # cannot enable VT mode.
        elif mode == b'ansi' and w32effects:
            win32.enablevtmode()
    elif mode == b'auto':
        realmode = b'ansi'

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

    if realmode == b'win32':
        ui._terminfoparams.clear()
        if not w32effects:
            modewarn()
            return None
    elif realmode == b'ansi':
        ui._terminfoparams.clear()
    elif realmode == b'terminfo':
        _terminfosetup(ui, mode, formatted)
        if not ui._terminfoparams:
            ## FIXME Shouldn't we return None in this case too?
            modewarn()
            realmode = b'ansi'
    else:
        return None

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


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


def _activeeffects(ui):
    '''Return the effects map for the color mode set on the ui.'''
    if ui._colormode == b'win32':
        return w32effects
    elif ui._colormode is not None:
        return _effects
    return {}


def valideffect(ui, effect):
    """Determine if the effect is valid or not."""
    return (not ui._terminfoparams and effect in _activeeffects(ui)) or (
        effect in ui._terminfoparams or effect[:-11] in ui._terminfoparams
    )


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

    bg = False
    if effect.endswith(b'_background'):
        bg = True
        effect = effect[:-11]
    try:
        attr, val, termcode = ui._terminfoparams[effect]
    except KeyError:
        return b''
    if attr:
        if termcode:
            return termcode
        else:
            return curses.tigetstr(pycompat.sysstr(val))
    elif bg:
        return curses.tparm(curses.tigetstr('setab'), val)
    else:
        return curses.tparm(curses.tigetstr('setaf'), val)


def _mergeeffects(text, start, stop):
    """Insert start sequence at every occurrence of stop sequence

    >>> s = _mergeeffects(b'cyan', b'[C]', b'|')
    >>> s = _mergeeffects(s + b'yellow', b'[Y]', b'|')
    >>> s = _mergeeffects(b'ma' + s + b'genta', b'[M]', b'|')
    >>> s = _mergeeffects(b'red' + s, b'[R]', b'|')
    >>> s
    '[R]red[M]ma[Y][C]cyan|[R][M][Y]yellow|[R][M]genta|'
    """
    parts = []
    for t in text.split(stop):
        if not t:
            continue
        parts.extend([start, t, stop])
    return b''.join(parts)


def _render_effects(ui, text, effects):
    """Wrap text in commands to turn on each effect."""
    if not text:
        return text
    if ui._terminfoparams:
        start = b''.join(
            _effect_str(ui, effect) for effect in [b'none'] + effects.split()
        )
        stop = _effect_str(ui, b'none')
    else:
        activeeffects = _activeeffects(ui)
        start = [
            pycompat.bytestr(activeeffects[e])
            for e in [b'none'] + effects.split()
        ]
        start = b'\033[' + b';'.join(start) + b'm'
        stop = b'\033[' + pycompat.bytestr(activeeffects[b'none']) + b'm'
    return _mergeeffects(text, start, stop)


_ansieffectre = re.compile(br'\x1b\[[0-9;]*m')


def stripeffects(text):
    """Strip ANSI control codes which could be inserted by colorlabel()"""
    return _ansieffectre.sub(b'', text)


def colorlabel(ui, msg, label):
    """add color control code according to the mode"""
    if ui._colormode == b'debug':
        if label and msg:
            if msg.endswith(b'\n'):
                msg = b"[%s|%s]\n" % (label, msg[:-1])
            else:
                msg = b"[%s|%s]" % (label, msg)
    elif ui._colormode is not None:
        effects = []
        for l in label.split():
            s = ui._styles.get(l, b'')
            if s:
                effects.append(s)
            elif valideffect(ui, l):
                effects.append(l)
        effects = b' '.join(effects)
        if effects:
            msg = b'\n'.join(
                [
                    _render_effects(ui, line, effects)
                    for line in msg.split(b'\n')
                ]
            )
    return msg


w32effects = None
if pycompat.iswindows:
    import ctypes

    _kernel32 = ctypes.windll.kernel32  # pytype: disable=module-attr

    _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 = 0xFFFFFFF5  # (DWORD)-11
    _STD_ERROR_HANDLE = 0xFFFFFFF4  # (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 = {
        b'none': -1,
        b'black': 0,
        b'red': _FOREGROUND_RED,
        b'green': _FOREGROUND_GREEN,
        b'yellow': _FOREGROUND_RED | _FOREGROUND_GREEN,
        b'blue': _FOREGROUND_BLUE,
        b'magenta': _FOREGROUND_BLUE | _FOREGROUND_RED,
        b'cyan': _FOREGROUND_BLUE | _FOREGROUND_GREEN,
        b'white': _FOREGROUND_RED | _FOREGROUND_GREEN | _FOREGROUND_BLUE,
        b'bold': _FOREGROUND_INTENSITY,
        b'black_background': 0x100,  # unused value > 0x0f
        b'red_background': _BACKGROUND_RED,
        b'green_background': _BACKGROUND_GREEN,
        b'yellow_background': _BACKGROUND_RED | _BACKGROUND_GREEN,
        b'blue_background': _BACKGROUND_BLUE,
        b'purple_background': _BACKGROUND_BLUE | _BACKGROUND_RED,
        b'cyan_background': _BACKGROUND_BLUE | _BACKGROUND_GREEN,
        b'white_background': (
            _BACKGROUND_RED | _BACKGROUND_GREEN | _BACKGROUND_BLUE
        ),
        b'bold_background': _BACKGROUND_INTENSITY,
        b'underline': _COMMON_LVB_UNDERSCORE,  # double-byte charsets only
        b'inverse': _COMMON_LVB_REVERSE_VIDEO,  # double-byte charsets only
    }

    passthrough = {
        _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(
                br'\033\[([^m]*)m([^\033]*)(.*)', re.MULTILINE | re.DOTALL
            )

    def win32print(ui, writefunc, text, **opts):
        label = opts.get('label', b'')
        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 = ui._styles.get(l, b'')
            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(b'\033['):
            text = b'\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(b';'):
                    if sattr:
                        attr = mapcolor(int(sattr), attr)
                ui.flush()
                _kernel32.SetConsoleTextAttribute(stdout, attr)
                writefunc(m.group(2))
                m = re.match(ansire, m.group(3))
        finally:
            # Explicitly reset original attributes
            ui.flush()
            _kernel32.SetConsoleTextAttribute(stdout, origattr)