# -*- coding: utf-8 -*- """ This is the Windows backend for keyboard events, and is implemented by invoking the Win32 API through the ctypes module. This is error prone and can introduce very unpythonic failure modes, such as segfaults and low level memory leaks. But it is also dependency-free, very performant well documented on Microsoft's webstie and scattered examples. # TODO: - Keypad numbers still print as numbers even when numlock is off. - No way to specify if user wants a keypad key or not in `map_char`. """ from __future__ import unicode_literals import re import atexit import traceback from threading import Lock from collections import defaultdict from ._keyboard_event import KeyboardEvent, KEY_DOWN, KEY_UP from ._canonical_names import normalize_name try: # Force Python2 to convert to unicode and not to str. chr = unichr except NameError: pass # This part is just declaring Win32 API structures using ctypes. In C # this would be simply #include "windows.h". import ctypes from ctypes import c_short, c_char, c_uint8, c_int32, c_int, c_uint, c_uint32, c_long, Structure, CFUNCTYPE, POINTER from ctypes.wintypes import WORD, DWORD, BOOL, HHOOK, MSG, LPWSTR, WCHAR, WPARAM, LPARAM, LONG, HMODULE, LPCWSTR, HINSTANCE, HWND LPMSG = POINTER(MSG) ULONG_PTR = POINTER(DWORD) kernel32 = ctypes.WinDLL('kernel32', use_last_error=True) GetModuleHandleW = kernel32.GetModuleHandleW GetModuleHandleW.restype = HMODULE GetModuleHandleW.argtypes = [LPCWSTR] #https://github.com/boppreh/mouse/issues/1 #user32 = ctypes.windll.user32 user32 = ctypes.WinDLL('user32', use_last_error = True) VK_PACKET = 0xE7 INPUT_MOUSE = 0 INPUT_KEYBOARD = 1 INPUT_HARDWARE = 2 KEYEVENTF_KEYUP = 0x02 KEYEVENTF_UNICODE = 0x04 class KBDLLHOOKSTRUCT(Structure): _fields_ = [("vk_code", DWORD), ("scan_code", DWORD), ("flags", DWORD), ("time", c_int), ("dwExtraInfo", ULONG_PTR)] # Included for completeness. class MOUSEINPUT(ctypes.Structure): _fields_ = (('dx', LONG), ('dy', LONG), ('mouseData', DWORD), ('dwFlags', DWORD), ('time', DWORD), ('dwExtraInfo', ULONG_PTR)) class KEYBDINPUT(ctypes.Structure): _fields_ = (('wVk', WORD), ('wScan', WORD), ('dwFlags', DWORD), ('time', DWORD), ('dwExtraInfo', ULONG_PTR)) class HARDWAREINPUT(ctypes.Structure): _fields_ = (('uMsg', DWORD), ('wParamL', WORD), ('wParamH', WORD)) class _INPUTunion(ctypes.Union): _fields_ = (('mi', MOUSEINPUT), ('ki', KEYBDINPUT), ('hi', HARDWAREINPUT)) class INPUT(ctypes.Structure): _fields_ = (('type', DWORD), ('union', _INPUTunion)) LowLevelKeyboardProc = CFUNCTYPE(c_int, WPARAM, LPARAM, POINTER(KBDLLHOOKSTRUCT)) SetWindowsHookEx = user32.SetWindowsHookExW SetWindowsHookEx.argtypes = [c_int, LowLevelKeyboardProc, HINSTANCE , DWORD] SetWindowsHookEx.restype = HHOOK CallNextHookEx = user32.CallNextHookEx #CallNextHookEx.argtypes = [c_int , c_int, c_int, POINTER(KBDLLHOOKSTRUCT)] CallNextHookEx.restype = c_int UnhookWindowsHookEx = user32.UnhookWindowsHookEx UnhookWindowsHookEx.argtypes = [HHOOK] UnhookWindowsHookEx.restype = BOOL GetMessage = user32.GetMessageW GetMessage.argtypes = [LPMSG, HWND, c_uint, c_uint] GetMessage.restype = BOOL TranslateMessage = user32.TranslateMessage TranslateMessage.argtypes = [LPMSG] TranslateMessage.restype = BOOL DispatchMessage = user32.DispatchMessageA DispatchMessage.argtypes = [LPMSG] keyboard_state_type = c_uint8 * 256 GetKeyboardState = user32.GetKeyboardState GetKeyboardState.argtypes = [keyboard_state_type] GetKeyboardState.restype = BOOL GetKeyNameText = user32.GetKeyNameTextW GetKeyNameText.argtypes = [c_long, LPWSTR, c_int] GetKeyNameText.restype = c_int MapVirtualKey = user32.MapVirtualKeyW MapVirtualKey.argtypes = [c_uint, c_uint] MapVirtualKey.restype = c_uint ToUnicode = user32.ToUnicode ToUnicode.argtypes = [c_uint, c_uint, keyboard_state_type, LPWSTR, c_int, c_uint] ToUnicode.restype = c_int SendInput = user32.SendInput SendInput.argtypes = [c_uint, POINTER(INPUT), c_int] SendInput.restype = c_uint # https://msdn.microsoft.com/en-us/library/windows/desktop/ms646307(v=vs.85).aspx MAPVK_VK_TO_CHAR = 2 MAPVK_VK_TO_VSC = 0 MAPVK_VSC_TO_VK = 1 MAPVK_VK_TO_VSC_EX = 4 MAPVK_VSC_TO_VK_EX = 3 VkKeyScan = user32.VkKeyScanW VkKeyScan.argtypes = [WCHAR] VkKeyScan.restype = c_short LLKHF_INJECTED = 0x00000010 WM_KEYDOWN = 0x0100 WM_KEYUP = 0x0101 WM_SYSKEYDOWN = 0x104 # Used for ALT key WM_SYSKEYUP = 0x105 # This marks the end of Win32 API declarations. The rest is ours. keyboard_event_types = { WM_KEYDOWN: KEY_DOWN, WM_KEYUP: KEY_UP, WM_SYSKEYDOWN: KEY_DOWN, WM_SYSKEYUP: KEY_UP, } # List taken from the official documentation, but stripped of the OEM-specific keys. # Keys are virtual key codes, values are pairs (name, is_keypad). official_virtual_keys = { 0x03: ('control-break processing', False), 0x08: ('backspace', False), 0x09: ('tab', False), 0x0c: ('clear', False), 0x0d: ('enter', False), 0x10: ('shift', False), 0x11: ('ctrl', False), 0x12: ('alt', False), 0x13: ('pause', False), 0x14: ('caps lock', False), 0x15: ('ime kana mode', False), 0x15: ('ime hanguel mode', False), 0x15: ('ime hangul mode', False), 0x17: ('ime junja mode', False), 0x18: ('ime final mode', False), 0x19: ('ime hanja mode', False), 0x19: ('ime kanji mode', False), 0x1b: ('esc', False), 0x1c: ('ime convert', False), 0x1d: ('ime nonconvert', False), 0x1e: ('ime accept', False), 0x1f: ('ime mode change request', False), 0x20: ('spacebar', False), 0x21: ('page up', False), 0x22: ('page down', False), 0x23: ('end', False), 0x24: ('home', False), 0x25: ('left', False), 0x26: ('up', False), 0x27: ('right', False), 0x28: ('down', False), 0x29: ('select', False), 0x2a: ('print', False), 0x2b: ('execute', False), 0x2c: ('print screen', False), 0x2d: ('insert', False), 0x2e: ('delete', False), 0x2f: ('help', False), 0x30: ('0', False), 0x31: ('1', False), 0x32: ('2', False), 0x33: ('3', False), 0x34: ('4', False), 0x35: ('5', False), 0x36: ('6', False), 0x37: ('7', False), 0x38: ('8', False), 0x39: ('9', False), 0x41: ('a', False), 0x42: ('b', False), 0x43: ('c', False), 0x44: ('d', False), 0x45: ('e', False), 0x46: ('f', False), 0x47: ('g', False), 0x48: ('h', False), 0x49: ('i', False), 0x4a: ('j', False), 0x4b: ('k', False), 0x4c: ('l', False), 0x4d: ('m', False), 0x4e: ('n', False), 0x4f: ('o', False), 0x50: ('p', False), 0x51: ('q', False), 0x52: ('r', False), 0x53: ('s', False), 0x54: ('t', False), 0x55: ('u', False), 0x56: ('v', False), 0x57: ('w', False), 0x58: ('x', False), 0x59: ('y', False), 0x5a: ('z', False), 0x5b: ('left windows', False), 0x5c: ('right windows', False), 0x5d: ('applications', False), 0x5f: ('sleep', False), 0x60: ('0', True), 0x61: ('1', True), 0x62: ('2', True), 0x63: ('3', True), 0x64: ('4', True), 0x65: ('5', True), 0x66: ('6', True), 0x67: ('7', True), 0x68: ('8', True), 0x69: ('9', True), 0x6a: ('*', True), 0x6b: ('+', True), 0x6c: ('separator', True), 0x6d: ('-', True), 0x6e: ('decimal', True), 0x6f: ('/', True), 0x70: ('f1', False), 0x71: ('f2', False), 0x72: ('f3', False), 0x73: ('f4', False), 0x74: ('f5', False), 0x75: ('f6', False), 0x76: ('f7', False), 0x77: ('f8', False), 0x78: ('f9', False), 0x79: ('f10', False), 0x7a: ('f11', False), 0x7b: ('f12', False), 0x7c: ('f13', False), 0x7d: ('f14', False), 0x7e: ('f15', False), 0x7f: ('f16', False), 0x80: ('f17', False), 0x81: ('f18', False), 0x82: ('f19', False), 0x83: ('f20', False), 0x84: ('f21', False), 0x85: ('f22', False), 0x86: ('f23', False), 0x87: ('f24', False), 0x90: ('num lock', False), 0x91: ('scroll lock', False), 0xa0: ('left shift', False), 0xa1: ('right shift', False), 0xa2: ('left ctrl', False), 0xa3: ('right ctrl', False), 0xa4: ('left menu', False), 0xa5: ('right menu', False), 0xa6: ('browser back', False), 0xa7: ('browser forward', False), 0xa8: ('browser refresh', False), 0xa9: ('browser stop', False), 0xaa: ('browser search key', False), 0xab: ('browser favorites', False), 0xac: ('browser start and home', False), 0xad: ('volume mute', False), 0xae: ('volume down', False), 0xaf: ('volume up', False), 0xb0: ('next track', False), 0xb1: ('previous track', False), 0xb2: ('stop media', False), 0xb3: ('play/pause media', False), 0xb4: ('start mail', False), 0xb5: ('select media', False), 0xb6: ('start application 1', False), 0xb7: ('start application 2', False), 0xbb: ('+', False), 0xbc: (',', False), 0xbd: ('-', False), 0xbe: ('.', False), #0xbe:('/', False), # Used for miscellaneous characters; it can vary by keyboard. For the US standard keyboard, the '/?. 0xe5: ('ime process', False), 0xf6: ('attn', False), 0xf7: ('crsel', False), 0xf8: ('exsel', False), 0xf9: ('erase eof', False), 0xfa: ('play', False), 0xfb: ('zoom', False), 0xfc: ('reserved ', False), 0xfd: ('pa1', False), 0xfe: ('clear', False), } tables_lock = Lock() to_name = defaultdict(list) from_name = defaultdict(list) scan_code_to_vk = {} distinct_modifiers = [ (), ('shift',), ('alt gr',), ('num lock',), ('shift', 'num lock'), ('caps lock',), ('shift', 'caps lock'), ('alt gr', 'num lock'), ] name_buffer = ctypes.create_unicode_buffer(32) unicode_buffer = ctypes.create_unicode_buffer(32) keyboard_state = keyboard_state_type() def get_event_names(scan_code, vk, is_extended, modifiers): is_keypad = (scan_code, vk, is_extended) in keypad_keys is_official = vk in official_virtual_keys if is_keypad and is_official: yield official_virtual_keys[vk][0] keyboard_state[0x10] = 0x80 * ('shift' in modifiers) keyboard_state[0x11] = 0x80 * ('alt gr' in modifiers) keyboard_state[0x12] = 0x80 * ('alt gr' in modifiers) keyboard_state[0x14] = 0x01 * ('caps lock' in modifiers) keyboard_state[0x90] = 0x01 * ('num lock' in modifiers) keyboard_state[0x91] = 0x01 * ('scroll lock' in modifiers) unicode_ret = ToUnicode(vk, scan_code, keyboard_state, unicode_buffer, len(unicode_buffer), 0) if unicode_ret and unicode_buffer.value: yield unicode_buffer.value # unicode_ret == -1 -> is dead key # ToUnicode has the side effect of setting global flags for dead keys. # Therefore we need to call it twice to clear those flags. # If your 6 and 7 keys are named "^6" and "^7", this is the reason. ToUnicode(vk, scan_code, keyboard_state, unicode_buffer, len(unicode_buffer), 0) name_ret = GetKeyNameText(scan_code << 16 | is_extended << 24, name_buffer, 1024) if name_ret and name_buffer.value: yield name_buffer.value char = user32.MapVirtualKeyW(vk, MAPVK_VK_TO_CHAR) & 0xFF if char != 0: yield chr(char) if not is_keypad and is_official: yield official_virtual_keys[vk][0] def _setup_name_tables(): """ Ensures the scan code/virtual key code/name translation tables are filled. """ with tables_lock: if to_name: return # Go through every possible scan code, and map them to virtual key codes. # Then vice-versa. all_scan_codes = [(sc, user32.MapVirtualKeyExW(sc, MAPVK_VSC_TO_VK_EX, 0)) for sc in range(0x100)] all_vks = [(user32.MapVirtualKeyExW(vk, MAPVK_VK_TO_VSC_EX, 0), vk) for vk in range(0x100)] for scan_code, vk in all_scan_codes + all_vks: # `to_name` and `from_name` entries will be a tuple (scan_code, vk, extended, shift_state). if (scan_code, vk, 0, 0, 0) in to_name: continue if scan_code not in scan_code_to_vk: scan_code_to_vk[scan_code] = vk # Brute force all combinations to find all possible names. for extended in [0, 1]: for modifiers in distinct_modifiers: entry = (scan_code, vk, extended, modifiers) # Get key names from ToUnicode, GetKeyNameText, MapVirtualKeyW and official virtual keys. names = list(get_event_names(*entry)) if names: # Also map lowercased key names, but only after the properly cased ones. lowercase_names = [name.lower() for name in names] to_name[entry] = names + lowercase_names # Remember the "id" of the name, as the first techniques # have better results and therefore priority. for i, name in enumerate(map(normalize_name, names + lowercase_names)): from_name[name].append((i, entry)) # TODO: single quotes on US INTL is returning the dead key (?), and therefore # not typing properly. # Alt gr is way outside the usual range of keys (0..127) and on my # computer is named as 'ctrl'. Therefore we add it manually and hope # Windows is consistent in its inconsistency. for extended in [0, 1]: for modifiers in distinct_modifiers: to_name[(541, 162, extended, modifiers)] = ['alt gr'] from_name['alt gr'].append((1, (541, 162, extended, modifiers))) modifiers_preference = defaultdict(lambda: 10) modifiers_preference.update({(): 0, ('shift',): 1, ('alt gr',): 2, ('ctrl',): 3, ('alt',): 4}) def order_key(line): i, entry = line scan_code, vk, extended, modifiers = entry return modifiers_preference[modifiers], i, extended, vk, scan_code for name, entries in list(from_name.items()): from_name[name] = sorted(set(entries), key=order_key) # Called by keyboard/__init__.py init = _setup_name_tables # List created manually. keypad_keys = [ # (scan_code, virtual_key_code, is_extended) (126, 194, 0), (126, 194, 0), (28, 13, 1), (28, 13, 1), (53, 111, 1), (53, 111, 1), (55, 106, 0), (55, 106, 0), (69, 144, 1), (69, 144, 1), (71, 103, 0), (71, 36, 0), (72, 104, 0), (72, 38, 0), (73, 105, 0), (73, 33, 0), (74, 109, 0), (74, 109, 0), (75, 100, 0), (75, 37, 0), (76, 101, 0), (76, 12, 0), (77, 102, 0), (77, 39, 0), (78, 107, 0), (78, 107, 0), (79, 35, 0), (79, 97, 0), (80, 40, 0), (80, 98, 0), (81, 34, 0), (81, 99, 0), (82, 45, 0), (82, 96, 0), (83, 110, 0), (83, 46, 0), ] shift_is_pressed = False altgr_is_pressed = False ignore_next_right_alt = False shift_vks = set([0x10, 0xa0, 0xa1]) def prepare_intercept(callback): """ Registers a Windows low level keyboard hook. The provided callback will be invoked for each high-level keyboard event, and is expected to return True if the key event should be passed to the next program, or False if the event is to be blocked. No event is processed until the Windows messages are pumped (see start_intercept). """ _setup_name_tables() def process_key(event_type, vk, scan_code, is_extended): global shift_is_pressed, altgr_is_pressed, ignore_next_right_alt #print(event_type, vk, scan_code, is_extended) # Pressing alt-gr also generates an extra "right alt" event if vk == 0xA5 and ignore_next_right_alt: ignore_next_right_alt = False return True modifiers = ( ('shift',) * shift_is_pressed + ('alt gr',) * altgr_is_pressed + ('num lock',) * (user32.GetKeyState(0x90) & 1) + ('caps lock',) * (user32.GetKeyState(0x14) & 1) + ('scroll lock',) * (user32.GetKeyState(0x91) & 1) ) entry = (scan_code, vk, is_extended, modifiers) if entry not in to_name: to_name[entry] = list(get_event_names(*entry)) names = to_name[entry] name = names[0] if names else None # TODO: inaccurate when holding multiple different shifts. if vk in shift_vks: shift_is_pressed = event_type == KEY_DOWN if scan_code == 541 and vk == 162: ignore_next_right_alt = True altgr_is_pressed = event_type == KEY_DOWN is_keypad = (scan_code, vk, is_extended) in keypad_keys return callback(KeyboardEvent(event_type=event_type, scan_code=scan_code or -vk, name=name, is_keypad=is_keypad)) def low_level_keyboard_handler(nCode, wParam, lParam): try: vk = lParam.contents.vk_code # Ignore the second `alt` DOWN observed in some cases. fake_alt = (LLKHF_INJECTED | 0x20) # Ignore events generated by SendInput with Unicode. if vk != VK_PACKET and lParam.contents.flags & fake_alt != fake_alt: event_type = keyboard_event_types[wParam] is_extended = lParam.contents.flags & 1 scan_code = lParam.contents.scan_code should_continue = process_key(event_type, vk, scan_code, is_extended) if not should_continue: return -1 except Exception as e: print('Error in keyboard hook:') traceback.print_exc() return CallNextHookEx(None, nCode, wParam, lParam) WH_KEYBOARD_LL = c_int(13) keyboard_callback = LowLevelKeyboardProc(low_level_keyboard_handler) handle = GetModuleHandleW(None) thread_id = DWORD(0) keyboard_hook = SetWindowsHookEx(WH_KEYBOARD_LL, keyboard_callback, handle, thread_id) # Register to remove the hook when the interpreter exits. Unfortunately a # try/finally block doesn't seem to work here. atexit.register(UnhookWindowsHookEx, keyboard_callback) def listen(callback): prepare_intercept(callback) msg = LPMSG() while not GetMessage(msg, 0, 0, 0): TranslateMessage(msg) DispatchMessage(msg) def map_name(name): _setup_name_tables() entries = from_name.get(name) if not entries: raise ValueError('Key name {} is not mapped to any known key.'.format(repr(name))) for i, entry in entries: scan_code, vk, is_extended, modifiers = entry yield scan_code or -vk, modifiers def _send_event(code, event_type): if code == 541: # Alt-gr is made of ctrl+alt. Just sending even 541 doesn't do anything. user32.keybd_event(0x11, code, event_type, 0) user32.keybd_event(0x12, code, event_type, 0) elif code > 0: vk = scan_code_to_vk.get(code, 0) user32.keybd_event(vk, code, event_type, 0) else: # Negative scan code is a way to indicate we don't have a scan code, # and the value actually contains the Virtual key code. user32.keybd_event(-code, 0, event_type, 0) def press(code): _send_event(code, 0) def release(code): _send_event(code, 2) def type_unicode(character): # This code and related structures are based on # http://stackoverflow.com/a/11910555/252218 surrogates = bytearray(character.encode('utf-16le')) presses = [] releases = [] for i in range(0, len(surrogates), 2): higher, lower = surrogates[i:i+2] structure = KEYBDINPUT(0, (lower << 8) + higher, KEYEVENTF_UNICODE, 0, None) presses.append(INPUT(INPUT_KEYBOARD, _INPUTunion(ki=structure))) structure = KEYBDINPUT(0, (lower << 8) + higher, KEYEVENTF_UNICODE | KEYEVENTF_KEYUP, 0, None) releases.append(INPUT(INPUT_KEYBOARD, _INPUTunion(ki=structure))) inputs = presses + releases nInputs = len(inputs) LPINPUT = INPUT * nInputs pInputs = LPINPUT(*inputs) cbSize = c_int(ctypes.sizeof(INPUT)) SendInput(nInputs, pInputs, cbSize) if __name__ == '__main__': _setup_name_tables() import pprint pprint.pprint(to_name) pprint.pprint(from_name) #listen(lambda e: print(e.to_json()) or True)