#!/usr/bin/python3 # -*- coding: utf-8 -*- # input-remapper - GUI for device specific keyboard mappings # Copyright (C) 2022 sezanzeb # # This file is part of input-remapper. # # input-remapper 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. # # input-remapper 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 input-remapper. If not, see . """Talking to the GUI helper that has root permissions. see gui.helper.helper """ from typing import Optional from evdev.ecodes import EV_REL from inputremapper.input_event import InputEvent from inputremapper.logger import logger from inputremapper.event_combination import EventCombination from inputremapper.groups import groups, GAMEPAD from inputremapper.ipc.pipe import Pipe from inputremapper.gui.helper import ( MSG_EVENT, MSG_GROUPS, CMD_TERMINATE, CMD_REFRESH_GROUPS, ) from inputremapper import utils from inputremapper.gui.active_preset import active_preset from inputremapper.user import USER DEBOUNCE_TICKS = 3 def will_report_up(ev_type): """Check if this event will ever report a key up (wheels).""" return ev_type != EV_REL class Reader: """Processes events from the helper for the GUI to use. Does not serve any purpose for the injection service. When a button was pressed, the newest keycode can be obtained from this object. GTK has get_key for keyboard keys, but Reader also has knowledge of buttons like the middle-mouse button. """ def __init__(self): self.previous_event = None self.previous_result = None self._unreleased = {} self._debounce_remove = {} self._groups_updated = False self._cleared_at = 0 self.group = None self._results = None self._commands = None self.connect() def connect(self): """Connect to the helper.""" self._results = Pipe(f"/tmp/input-remapper-{USER}/results") self._commands = Pipe(f"/tmp/input-remapper-{USER}/commands") def are_new_groups_available(self): """Check if groups contains new devices. The ui should then update its list. """ outdated = self._groups_updated self._groups_updated = False # assume the ui will react accordingly return outdated def _get_event(self, message) -> Optional[InputEvent]: """Return an InputEvent if the message contains one. None otherwise.""" message_type = message["type"] message_body = message["message"] if message_type == MSG_GROUPS: if message_body != groups.dumps(): groups.loads(message_body) logger.debug("Received %d devices", len(groups)) self._groups_updated = True return None if message_type == MSG_EVENT: return InputEvent(*message_body) logger.error('Received unknown message "%s"', message) return None def read(self): """Get the newest key/combination as EventCombination object. Only reports keys from down-events. On key-down events the pipe returns changed combinations. Release events won't cause that and the reader will return None as in "nothing new to report". So In order to change a combination, one of its keys has to be released and then a different one pressed. Otherwise making combinations wouldn't be possible. Because at some point the keys have to be released, and that shouldn't cause the combination to get trimmed. """ # this is in some ways similar to the keycode_mapper and # joystick_to_mouse, but its much simpler because it doesn't # have to trigger anything, manage any macros and only # reports key-down events. This function is called periodically # by the window. # remember the previous down-event from the pipe in order to # be able to tell if the reader should return the updated combination previous_event = self.previous_event key_down_received = False self._debounce_tick() while self._results.poll(): message = self._results.recv() event = self._get_event(message) if event is None: continue gamepad = GAMEPAD in self.group.types if not utils.should_map_as_btn(event, active_preset, gamepad): continue if event.value == 0: logger.debug_key(event, "release") self._release(event.type_and_code) continue if self._unreleased.get(event.type_and_code) == event: logger.debug_key(event, "duplicate key down") self._debounce_start(event.event_tuple) continue # to keep track of combinations. # "I have got this release event, what was this for?" A release # event for a D-Pad axis might be any direction, hence this maps # from release to input in order to remember it. Since all release # events have value 0, the value is not used in the combination. key_down_received = True logger.debug_key(event, "down") self._unreleased[event.type_and_code] = event self._debounce_start(event.event_tuple) previous_event = event if not key_down_received: # This prevents writing a subset of the combination into # result after keys were released. In order to control the gui, # they have to be released. return None self.previous_event = previous_event if len(self._unreleased) > 0: result = EventCombination(self._unreleased.values()) if result == self.previous_result: # don't return the same stuff twice return None self.previous_result = result logger.debug_key(result, "read result") return result return None def start_reading(self, group): """Start reading keycodes for a device.""" logger.debug('Sending start msg to helper for "%s"', group.key) self._commands.send(group.key) self.group = group self.clear() def terminate(self): """Stop reading keycodes for good.""" logger.debug("Sending close msg to helper") self._commands.send(CMD_TERMINATE) def refresh_groups(self): """Ask the helper for new device groups.""" self._commands.send(CMD_REFRESH_GROUPS) def clear(self): """Next time when reading don't return the previous keycode.""" logger.debug("Clearing reader") while self._results.poll(): # clear the results pipe and handle any non-event messages, # otherwise a 'groups' message might get lost message = self._results.recv() self._get_event(message) self._unreleased = {} self.previous_event = None self.previous_result = None def get_unreleased_keys(self): """Get a EventCombination object of the current keyboard state.""" unreleased = list(self._unreleased.values()) if len(unreleased) == 0: return None return EventCombination(unreleased) def _release(self, type_code): """Modify the state to recognize the releasing of the key.""" if type_code in self._unreleased: del self._unreleased[type_code] if type_code in self._debounce_remove: del self._debounce_remove[type_code] def _debounce_start(self, event_tuple): """Act like the key was released if no new event arrives in time.""" if not will_report_up(event_tuple[0]): self._debounce_remove[event_tuple[:2]] = DEBOUNCE_TICKS def _debounce_tick(self): """If the counter reaches 0, the key is not considered held down.""" for type_code in list(self._debounce_remove.keys()): if type_code not in self._unreleased: continue # clear wheel events from unreleased after some time if self._debounce_remove[type_code] == 0: logger.debug_key(self._unreleased[type_code], "Considered as released") self._release(type_code) else: self._debounce_remove[type_code] -= 1 reader = Reader()