input-remapper/keymapper/X.py
2020-11-05 01:24:56 +01:00

256 lines
8.4 KiB
Python

#!/usr/bin/python3
# -*- coding: utf-8 -*-
# key-mapper - GUI for device specific keyboard mappings
# Copyright (C) 2020 sezanzeb <proxima@hip70890b.de>
#
# This file is part of key-mapper.
#
# key-mapper 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.
#
# key-mapper 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 key-mapper. If not, see <https://www.gnu.org/licenses/>.
"""Stuff that interacts with the X Server, be it commands or config files.
TODO create a base class to standardize the interface if a different
display server should be supported.
Resources:
[1] https://wiki.archlinux.org/index.php/Keyboard_input
[2] http://people.uleth.ca/~daniel.odonnell/Blog/custom-keyboard-in-linuxx11
[3] https://www.x.org/releases/X11R7.7/doc/xorg-docs/input/XKB-Enhancing.html
"""
import os
import re
import subprocess
from keymapper.paths import get_home_path, get_usr_path, KEYCODES_PATH, \
CONFIG_PATH, SYMBOLS_PATH
from keymapper.logger import logger
from keymapper.data import get_data_path
from keymapper.presets import get_presets
from keymapper.linux import get_devices, can_grab
def ensure_symlink():
"""Make sure the symlink exists.
It provides the configs in /home to X11 in /usr.
"""
if not os.path.exists(SYMBOLS_PATH):
# link from /usr/share/X11/xkb/symbols/key-mapper/user to
# /home/user/.config/key-mapper
logger.info('Linking "%s" to "%s"', SYMBOLS_PATH, CONFIG_PATH)
os.makedirs(os.path.dirname(SYMBOLS_PATH), exist_ok=True)
os.symlink(CONFIG_PATH, SYMBOLS_PATH, target_is_directory=True)
def create_preset(device, name=None):
"""Create an empty preset and return the name."""
existing_names = get_presets(device)
if name is None:
name = 'new preset'
# find a name that is not already taken
if os.path.exists(get_home_path(device, name)):
i = 2
while os.path.exists(get_home_path(device, f'{name} {i}')):
i += 1
name = f'{name} {i}'
os.mknod(get_home_path(device, name))
ensure_symlink()
return name
def create_setxkbmap_config(device, preset, mappings):
"""Generate a config file for setxkbmap.
The file is created in ~/.config/key-mapper/<device>/<preset> and,
in order to find all presets in the home dir to make backing them up
more intuitive, a symlink is created in
/usr/share/X11/xkb/symbols/key-mapper/<device>/<preset> to point to it.
The file in home doesn't have underscore to be more beautiful on the
frontend, while the symlink doesn't contain any whitespaces.
Parameters
----------
device : string
preset : string
mappings : list
List of (keycode, character) tuples
"""
if len(mappings) == 0:
logger.debug('Got empty mappings')
return None
create_identity_mapping()
home_device_path = get_home_path(device)
if not os.path.exists(home_device_path):
logger.info('Creating directory "%s"', home_device_path)
os.makedirs(home_device_path, exist_ok=True)
ensure_symlink()
home_preset_path = get_home_path(device, preset)
if not os.path.exists(home_preset_path):
logger.info('Creating config file "%s"', home_preset_path)
os.mknod(home_preset_path)
logger.info('Writing key mappings')
with open(home_preset_path, 'w') as f:
contents = generate_symbols_file_content(device, preset, mappings)
if contents is not None:
f.write(contents)
def apply_preset(device, preset):
"""Apply a preset to the device."""
group = get_devices()[device]
# apply it to every device that hangs on the same usb port, because I
# have no idea how to figure out which one of those 3 devices that are
# all named after my mouse to use.
for xinput_name, xinput_id in get_xinput_id_mapping():
if xinput_name not in group['devices']:
# only all virtual devices of the same hardware device
continue
symbols = '/usr/share/X11/xkb/symbols/'
layout_path = get_usr_path(device, preset)
with open(layout_path, 'r') as f:
if f.read() == '':
logger.error('Tried to load empty config')
return
layout_name = layout_path[len(symbols):]
cmd = [
'setxkbmap',
'-layout', layout_name,
'-keycodes', 'key-mapper',
'-device', str(xinput_id)
]
logger.debug('Running `%s`', ' '.join(cmd))
subprocess.run(cmd)
def create_identity_mapping():
"""Because the concept of "reasonable symbolic names" [3] doesn't apply
when mouse buttons are all over the place. Create an identity mapping
to make generating "symbols" files easier. Keycode 10 -> "<10>"
This has the added benefit that keycodes reported by xev can be
identified in the symbols file.
"""
# TODO don't create this again if it already exists, as soon as this
# stuff is stable.
xkb_keycodes = []
# the maximum specified in /usr/share/X11/xkb/keycodes is usually 255
# and the minimum 8
maximum = 255
minimum = 8
for code in range(minimum, maximum + 1):
xkb_keycodes.append(f'<{code}> = {code};')
template_path = get_data_path('xkb_keycodes_template')
with open(template_path, 'r') as template_file:
template = template_file.read()
result = template.format(
minimum=minimum,
maximum=maximum,
xkb_keycodes='\n '.join(xkb_keycodes)
)
if not os.path.exists(KEYCODES_PATH):
logger.info('Creating "%s"', KEYCODES_PATH)
with open(KEYCODES_PATH, 'w') as keycodes:
keycodes.write(result)
def generate_symbols_file_content(device, preset, mappings):
"""Create config contents to be placed in /usr/share/X11/xkb/symbols.
Parameters
----------
device : string
preset : string
mappings : array
tuples of code, character
"""
system_default = 'us' # TODO get the system default
# If the symbols file contains key codes that are not present in
# the keycodes file, THE WHOLE X SESSION WILL CRASH!
if not os.path.exists(KEYCODES_PATH):
raise ValueError('Expected the keycodes file to exist.')
with open(KEYCODES_PATH, 'r') as f:
keycodes = re.findall(r'<.+?>', f.read())
xkb_symbols = []
for code, character in mappings:
if f'<{code}>' not in keycodes:
logger.error(f'Unknown keycode <{code}> for "{character}"')
# continue, otherwise X would crash when loading
continue
xkb_symbols.append(f'key <{code}> {{ [ {character} ] }};')
if len(xkb_symbols) == 0:
logger.error('Failed to populate xkb_symbols')
return None
template_path = get_data_path('xkb_symbols_template')
with open(template_path, 'r') as template_file:
template = template_file.read()
result = template.format(
name=f'{device}/{preset}',
xkb_symbols='\n '.join(xkb_symbols),
system_default=system_default
)
return result
def get_xinput_id_mapping():
"""Run xinput and get a list of name, id tuplies.
The ids are needed for setxkbmap. There might be duplicate names with
different ids.
"""
names = subprocess.check_output(
['xinput', 'list', '--name-only']
).decode().split('\n')
ids = subprocess.check_output(
['xinput', 'list', '--id-only']
).decode().split('\n')
names = [name for name in names if name != '']
ids = [int(id) for id in ids if id != '']
return zip(names, ids)
def get_mappings(device, preset):
"""Parse the X config to get a current mapping.
Returns tuples of (keycode, character)
"""
with open(get_home_path(device, preset), 'r') as f:
# from "key <12> { [ 1 ] };" extract 12 and 1,
# avoid lines that start with special characters (might be comments)
result = re.findall(r'\n\s+?key <(.+?)>.+?\[\s+(\w+)', f.read())
logger.debug('Found %d mappings in this preset', len(result))
return result