152 lines
5.0 KiB
Python
152 lines
5.0 KiB
Python
|
# Copyright 2020 Canonical, Ltd.
|
||
|
#
|
||
|
# This program is free software: you can redistribute it and/or modify
|
||
|
# it under the terms of the GNU Affero 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 Affero General Public License for more details.
|
||
|
#
|
||
|
# You should have received a copy of the GNU Affero General Public License
|
||
|
# along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||
|
|
||
|
import fcntl
|
||
|
import logging
|
||
|
import os
|
||
|
import sys
|
||
|
import tty
|
||
|
|
||
|
import urwid
|
||
|
|
||
|
from subiquitycore.palette import COLORS, urwid_8_names
|
||
|
|
||
|
log = logging.getLogger('subiquitycore.screen')
|
||
|
|
||
|
|
||
|
# From uapi/linux/kd.h:
|
||
|
KDGKBTYPE = 0x4B33 # get keyboard type
|
||
|
|
||
|
GIO_CMAP = 0x4B70 # gets colour palette on VGA+
|
||
|
PIO_CMAP = 0x4B71 # sets colour palette on VGA+
|
||
|
UO_R, UO_G, UO_B = 0xe9, 0x54, 0x20
|
||
|
|
||
|
|
||
|
class SubiquityScreen(urwid.raw_display.Screen):
|
||
|
|
||
|
# This class fixes a bug in urwid's screen:
|
||
|
#
|
||
|
# Calling screen.stop() sends the INPUT_DESCRIPTORS_CHANGED signal. This
|
||
|
# calls _reset_input_descriptors() which calls unhook_event_loop /
|
||
|
# hook_event_loop on the screen. But this all happens before _started is
|
||
|
# set to False on the screen and so this does not actually do anything. If
|
||
|
# we call stop and then, for example, run bash, we end up attempting to
|
||
|
# read from stdin while in a background process group and that gets the
|
||
|
# kernel upset at us.
|
||
|
#
|
||
|
# The cleanest fix seems to be to just send the signal again once stop()
|
||
|
# has returned which, now that screen._started is False, correctly stops
|
||
|
# listening from stdin.
|
||
|
#
|
||
|
# There is an exactly analagous problem with screen.start() except there
|
||
|
# the symptom is that we are running in the foreground but not listening to
|
||
|
# stdin! The fix is the same.
|
||
|
|
||
|
def start(self):
|
||
|
super().start()
|
||
|
urwid.emit_signal(self, urwid.display_common.INPUT_DESCRIPTORS_CHANGED)
|
||
|
# We run the terminal in raw, not cbreak mode.
|
||
|
fd = self._term_input_file.fileno()
|
||
|
if os.isatty(fd):
|
||
|
tty.setraw(fd)
|
||
|
|
||
|
def stop(self):
|
||
|
super().stop()
|
||
|
urwid.emit_signal(self, urwid.display_common.INPUT_DESCRIPTORS_CHANGED)
|
||
|
|
||
|
|
||
|
class LinuxScreen(SubiquityScreen):
|
||
|
|
||
|
def __init__(self, colors, **kwargs):
|
||
|
self._colors = colors
|
||
|
super().__init__(**kwargs)
|
||
|
|
||
|
def start(self):
|
||
|
self.curpal = bytearray(16*3)
|
||
|
fcntl.ioctl(sys.stdout.fileno(), GIO_CMAP, self.curpal)
|
||
|
newpal = self.curpal.copy()
|
||
|
for i in range(8):
|
||
|
for j in range(3):
|
||
|
newpal[i*3+j] = self._colors[i][1][j]
|
||
|
fcntl.ioctl(self._term_input_file.fileno(), PIO_CMAP, newpal)
|
||
|
super().start()
|
||
|
|
||
|
def stop(self):
|
||
|
fcntl.ioctl(self._term_input_file.fileno(), PIO_CMAP, self.curpal)
|
||
|
super().stop()
|
||
|
|
||
|
|
||
|
class TwentyFourBitScreen(SubiquityScreen):
|
||
|
|
||
|
def __init__(self, colors, **kwargs):
|
||
|
self._urwid_name_to_rgb = {
|
||
|
n: colors[i][1] for i, n in enumerate(urwid_8_names)}
|
||
|
super().__init__(**kwargs)
|
||
|
|
||
|
def _cc(self, color):
|
||
|
"""Return the "SGR" parameter for selecting color.
|
||
|
|
||
|
See https://en.wikipedia.org/wiki/ANSI_escape_code#SGR for an
|
||
|
explanation. We use the basic codes for black/white/default for
|
||
|
maximum compatibility; they are the only colors used when the
|
||
|
mono palette is selected.
|
||
|
"""
|
||
|
if color == 'white':
|
||
|
return '7'
|
||
|
elif color == 'black':
|
||
|
return '0'
|
||
|
elif color == 'default':
|
||
|
return '9'
|
||
|
else:
|
||
|
# This is almost but not quite a ISO 8613-3 code -- that
|
||
|
# would use colons to separate the rgb values instead. But
|
||
|
# it's what xterm, and hence everything else, supports.
|
||
|
return '8;2;{};{};{}'.format(*self._urwid_name_to_rgb[color])
|
||
|
|
||
|
def _attrspec_to_escape(self, a):
|
||
|
return '\x1b[0;3{};4{}m'.format(
|
||
|
self._cc(a.foreground),
|
||
|
self._cc(a.background))
|
||
|
|
||
|
|
||
|
_is_linux_tty = None
|
||
|
|
||
|
|
||
|
def is_linux_tty():
|
||
|
global _is_linux_tty
|
||
|
if _is_linux_tty is None:
|
||
|
try:
|
||
|
r = fcntl.ioctl(sys.stdout.fileno(), KDGKBTYPE, ' ')
|
||
|
except IOError as e:
|
||
|
log.debug("KDGKBTYPE failed %r", e)
|
||
|
return False
|
||
|
log.debug("KDGKBTYPE returned %r, is_linux_tty %s", r, r == b'\x02')
|
||
|
_is_linux_tty = r == b'\x02'
|
||
|
return _is_linux_tty
|
||
|
|
||
|
|
||
|
def make_screen(ascii=False, inputf=None, outputf=None):
|
||
|
""" """
|
||
|
if inputf is None:
|
||
|
inputf = sys.stdin
|
||
|
if outputf is None:
|
||
|
outputf = sys.stdout
|
||
|
if is_linux_tty():
|
||
|
return LinuxScreen(COLORS, input=inputf, output=outputf)
|
||
|
elif ascii:
|
||
|
return SubiquityScreen(input=inputf, output=outputf)
|
||
|
else:
|
||
|
return TwentyFourBitScreen(COLORS, input=inputf, output=outputf)
|