internals: document compression negotiation
As part of adding zstd support to all of the things, we'll need
to teach the wire protocol to support non-zlib compression formats.
This commit documents how we'll implement that.
To understand how we arrived at this proposal, let's look at how
things are done today.
The wire protocol today doesn't have a unified format. Instead,
there is a limited facility for differentiating replies as successful
or not. And, each command essentially defines its own response format.
A significant deficiency in the current protocol is the lack of
payload framing over the SSH transport. In the HTTP transport,
chunked transfer is used and the end of an HTTP response body (and
the end of a Mercurial command response) can be identified by a 0
length chunk. This is how HTTP chunked transfer works. But in the
SSH transport, there is no such framing, at least for certain
responses (notably the response to "getbundle" requests). Clients
can't simply read until end of stream because the socket is
persistent and reused for multiple requests. Clients need to know
when they've encountered the end of a request but there is nothing
simple for them to key off of to detect this. So what happens is
the client must decode the payload (as opposed to being dumb and
forwarding frames/packets). This means the payload itself needs
to support identifying end of stream. In some cases (bundle2), it
also means the payload can encode "error" or "interrupt" events
telling the client to e.g. abort processing. The lack of framing
on the SSH transport and the transfer of its responsibilities to
e.g. bundle2 is a massive layering violation and a wart on the
protocol architecture. It needs to be fixed someday by inventing a
proper framing protocol.
So about compression.
The client transport abstractions have a "_callcompressable()"
API. This API is called to invoke a remote command that will
send a compressible response. The response is essentially a
"streaming" response (no framing data at the Mercurial layer)
that is fed into a decompressor.
On the HTTP transport, the decompressor is zlib and only zlib.
There is currently no mechanism for the client to specify an
alternate compression format. And, clients don't advertise what
compression formats they support or ask the server to send a
specific compression format. Instead, it is assumed that non-error
responses to "compressible" commands are zlib compressed.
On the SSH transport, there is no compression at the Mercurial
protocol layer. Instead, compression must be handled by SSH
itself (e.g. `ssh -C`) or within the payload data (e.g. bundle
compression).
For the HTTP transport, adding new compression formats is pretty
straightforward. Once you know what decompressor to use, you can
stream data into the decompressor until you reach a 0 size HTTP
chunk, at which point you are at end of stream.
So our wire protocol changes for the HTTP transport are pretty
straightforward: the client and server advertise what compression
formats they support and an appropriate compression format is
chosen. We introduce a new HTTP media type to hold compressed
payloads. The header of the payload defines the compression format
being used. Whoever is on the receiving end can sniff the first few
bytes route to an appropriate decompressor.
Support for multiple compression formats is advertised on both
server and client. The server advertises a "compression" capability
saying which compression formats it supports and in what order they
are preferred. Clients advertise their support for multiple
compression formats and media types via the introduced "X-HgProto"
request header.
Strictly speaking, servers don't need to advertise which compression
formats they support. But doing so allows clients to fail fast if
they don't support any of the formats the server does. This is useful
in situations like sending bundles, where the client may have to
perform expensive computation before sending data to the server.
Rather than simply advertise a list of supported compression formats,
we introduce an additional "httpmediatype" server capability
advertising which media types the server supports. This means servers
are explicit about what formats they exchange. IMO, this is superior
to inferring support from other capabilities (like "compression").
By advertising compression support on each request in the "X-HgProto"
header and media type and direction at the server level, we are able
to gradually transition existing commands/responses to the new media
type and possibly compression. Contrast with the old world, where we
only supported a single media type and the use of compression was
built-in to the semantics of the command on both client and server.
In the new world, if "application/mercurial-0.2" is supported,
compression is supported. It's that simple.
It's worth noting that we explicitly don't use "Accept,"
"Accept-Encoding," "Content-Encoding," or "Transfer-Encoding" for
content negotiation and compression. People knowledgeable of the HTTP
specifications will say that we should use these because that's
what they are designed to be used for. They have a point and I
sympathize with the argument. Earlier versions of this commit even
defined supported media types in the "Accept" header. However, my
years of experience rolling out services leveraging HTTP has taught
me to not trust the HTTP layer, especially if you are going outside
the normal spec (such as using a custom "Content-Encoding" value to
represent zstd streams). I've seen load balancers, proxies, and other
network devices do very bad and unexpected things to HTTP messages
(like insisting zlib compressed content is decoded and then re-encoded
at a different compression level or even stripping compression
completely). I've found that the best way to avoid surprises when
writing protocols on top of HTTP is to use HTTP as a dumb transport as
much as possible to minimize the chances that an "intelligent" agent
between endpoints will muck with your data. While the widespread use of
TLS is mitigating many intermediate network agents interfering with
HTTP, there are still problems at the edges, with e.g. the origin HTTP
server needing to convert HTTP to and from WSGI and buggy or
feature-lacking HTTP client implementations. I've found the best way to
avoid these problems is to avoid using headers like "Content-Encoding"
and to bake as much logic as possible into media types and HTTP message
bodies. The protocol changes in this commit do rely on a custom HTTP
request header and the "Content-Type" headers. But we used them before,
so we shouldn't be increasing our exposure to "bad" HTTP agents.
For the SSH transport, we can't easily implement content negotiation
to determine compression formats because the SSH transport has no
content negotiation capabilities today. And without a framing protocol,
we don't know how much data to feed into a decompressor. So in order
to implement compression support on the SSH transport, we'd need to
invent a mechanism to represent content types and an outer framing
protocol to stream data robustly. While I'm fully capable of doing
that, it is a lot of work and not something that should be undertaken
lightly. My opinion is that if we're going to change the SSH transport
protocol, we should take a long hard look at implementing a grand
unified protocol that attempts to address all the deficiencies with
the existing protocol. While I want this to happen, that would be
massive scope bloat standing in the way of zstd support. So, I've
decided to take the easy solution: the SSH transport will not gain
support for multiple compression formats. Keep in mind it doesn't
support *any* compression today. So essentially nothing is changing
on the SSH front.
# color.py color output for Mercurial commands
#
# Copyright (C) 2007 Kevin Christen <kevin.christen@gmail.com>
#
# 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.
If the terminfo entry for your terminal is missing codes for an effect
or has the wrong codes, you can add or override those codes in your
configuration::
[color]
terminfo.dim = \E[2m
where '\E' is substituted with an escape character.
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
from mercurial.i18n import _
from mercurial import (
cmdutil,
color,
commands,
dispatch,
encoding,
extensions,
pycompat,
subrepo,
ui as uimod,
util,
)
cmdtable = {}
command = cmdutil.command(cmdtable)
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' 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 = 'ships-with-hg-core'
# 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.'''
# 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.'))
_terminfo_params.update((key[9:], (True, '', val.replace('\\E', '\x1b')))
for key, val in ui.configitems('color')
if key.startswith('terminfo.'))
try:
curses.setupterm()
except curses.error as e:
_terminfo_params.clear()
return
for key, (b, e, c) in _terminfo_params.items():
if not b:
continue
if not c and 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.clear()
def _modesetup(ui, coloropt):
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 (encoding.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 pycompat.osname == 'nt':
term = encoding.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
# a formatted terminal
if mode == realmode and ui.formatted():
ui.warn(_('warning: failed to set color mode to %s\n') % mode)
if realmode == 'win32':
_terminfo_params.clear()
if not w32effects:
modewarn()
return None
_effects.update(w32effects)
elif realmode == 'ansi':
_terminfo_params.clear()
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 raw code) 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 = {}
def _effect_str(effect):
'''Helper function for render_effects().'''
bg = False
if effect.endswith('_background'):
bg = True
effect = effect[:-11]
try:
attr, val, termcode = _terminfo_params[effect]
except KeyError:
return ''
if attr:
if termcode:
return termcode
else:
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 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.', 'terminfo.')):
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))
color._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 = color._styles.get(l, '')
if s:
effects.append(s)
elif valideffect(l):
effects.append(l)
effects = ' '.join(effects)
if effects:
return '\n'.join([render_effects(line, effects)
for line 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':
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',
[('', 'style', None, _('show all configured styles'))],
'hg debugcolor')
def debugcolor(ui, repo, **opts):
"""show available color, effects or style"""
ui.write(('color mode: %s\n') % ui._colormode)
if opts.get('style'):
return _debugdisplaystyle(ui)
else:
return _debugdisplaycolor(ui)
def _debugdisplaycolor(ui):
oldstyle = color._styles.copy()
try:
color._styles.clear()
for effect in _effects.keys():
color._styles[effect] = effect
if _terminfo_params:
for k, v in ui.configitems('color'):
if k.startswith('color.'):
color._styles[k] = k[6:]
elif k.startswith('terminfo.'):
color._styles[k] = k[9:]
ui.write(_('available colors:\n'))
# sort label with a '_' after the other to group '_background' entry.
items = sorted(color._styles.items(),
key=lambda i: ('_' in i[0], i[0], i[1]))
for colorname, label in items:
ui.write(('%s\n') % colorname, label=label)
finally:
color._styles.clear()
color._styles.update(oldstyle)
def _debugdisplaystyle(ui):
ui.write(_('available style:\n'))
width = max(len(s) for s in color._styles)
for label, effects in sorted(color._styles.items()):
ui.write('%s' % label, label=label)
if effects:
# 50
ui.write(': ')
ui.write(' ' * (max(0, width - len(label))))
ui.write(', '.join(ui.label(e, e) for e in effects.split()))
ui.write('\n')
if pycompat.osname != '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 = 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 = {
'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 = color._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)