Current File : //usr/lib/python3/dist-packages/samba/colour.py
# ANSI codes for 4 bit and xterm-256color
#
# Copyright (C) Andrew Bartlett 2018
#
# Originally written by Douglas Bagnall
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# The 4 bit colours are available as global variables with names like
# RED, DARK_RED, REV_RED (for red background), and REV_DARK_RED. If
# switch_colour_off() is called, these names will all point to the
# empty string. switch_colour_on() restores the default values.
#
# The 256-colour codes are obtained using xterm_256_color(n), where n
# is the number of the desired colour.
def _gen_ansi_colours():
g = globals()
for i, name in enumerate(('BLACK', 'RED', 'GREEN', 'YELLOW', 'BLUE',
'MAGENTA', 'CYAN', 'WHITE')):
g[name] = "\033[1;3%dm" % i
g['DARK_' + name] = "\033[3%dm" % i
g['REV_' + name] = "\033[1;4%dm" % i
g['REV_DARK_' + name] = "\033[4%dm" % i
# kcc.debug uses these aliases (which make visual sense)
g['PURPLE'] = DARK_MAGENTA
g['GREY'] = DARK_WHITE
# C_NORMAL resets to normal, whatever that is
g['C_NORMAL'] = "\033[0m"
# Non-colour ANSI codes.
g['UNDERLINE'] = "\033[4m"
_gen_ansi_colours()
# Generate functions that colour a string. The functions look like
# this:
#
# c_BLUE("hello") # "\033[1;34mhello\033[0m" -> blue text
# c_DARK_RED(3) # 3 will be stringified and coloured
#
# but if colour is switched off, no colour codes are added.
#
# c_BLUE("hello") # "hello"
#
# The definition of the functions looks a little odd, because we want
# to bake in the name of the colour but not its actual value.
for _k in list(globals().keys()):
if _k.isupper():
def _f(s, name=_k):
return "%s%s%s" % (globals()[name], s, C_NORMAL)
globals()['c_%s' % _k] = _f
del _k, _f
def switch_colour_off():
"""Convert all the ANSI colour codes into empty strings."""
g = globals()
for k, v in list(g.items()):
if k.isupper() and isinstance(v, str) and v.startswith('\033'):
g[k] = ''
def switch_colour_on():
"""Regenerate all the ANSI colour codes."""
_gen_ansi_colours()
def xterm_256_colour(n, bg=False, bold=False):
weight = '01;' if bold else ''
target = '48' if bg else '38'
return "\033[%s%s;5;%dm" % (weight, target, int(n))
def is_colour_wanted(*streams, hint='auto'):
"""The hint is presumably a --color argument.
The streams to be considered can be file objects or file names,
with '-' being a special filename indicating stdout.
We follow the behaviour of GNU `ls` in what we accept.
* `git` is stricter, accepting only {always,never,auto}.
* `grep` is looser, accepting mixed case variants.
* historically we have used {yes,no,auto}.
* {always,never,auto} appears the commonest convention.
* if the caller tries to opt out of choosing and sets hint to None
or '', we assume 'auto'.
"""
if hint in ('no', 'never', 'none'):
return False
if hint in ('yes', 'always', 'force'):
return True
if hint not in ('auto', 'tty', 'if-tty', None, ''):
raise ValueError("unexpected colour hint: {hint}; "
"try always|never|auto")
from os import environ
if environ.get('NO_COLOR'):
# Note: per spec, we treat the empty string as if unset.
return False
for stream in streams:
if isinstance(stream, str):
# This function can be passed filenames instead of file
# objects, in which case we treat '-' as stdout, and test
# that. Any other string is not regarded as a tty.
if stream != '-':
return False
import sys
stream = sys.stdout
if not stream.isatty():
return False
return True
def colour_if_wanted(*streams, hint='auto'):
wanted = is_colour_wanted(*streams, hint=hint)
if wanted:
switch_colour_on()
else:
switch_colour_off()
return wanted
Mini Shell