Files
galaxy-integrations-python-api/src/galaxy/registry_monitor.py
2019-11-04 14:26:26 +01:00

100 lines
2.9 KiB
Python

import sys
if sys.platform == "win32":
import logging
import ctypes
from ctypes.wintypes import LONG, HKEY, LPCWSTR, DWORD, BOOL, HANDLE, LPVOID
LPSECURITY_ATTRIBUTES = LPVOID
RegOpenKeyEx = ctypes.windll.advapi32.RegOpenKeyExW
RegOpenKeyEx.restype = LONG
RegOpenKeyEx.argtypes = [HKEY, LPCWSTR, DWORD, DWORD, ctypes.POINTER(HKEY)]
RegCloseKey = ctypes.windll.advapi32.RegCloseKey
RegCloseKey.restype = LONG
RegCloseKey.argtypes = [HKEY]
RegNotifyChangeKeyValue = ctypes.windll.advapi32.RegNotifyChangeKeyValue
RegNotifyChangeKeyValue.restype = LONG
RegNotifyChangeKeyValue.argtypes = [HKEY, BOOL, DWORD, HANDLE, BOOL]
CloseHandle = ctypes.windll.kernel32.CloseHandle
CloseHandle.restype = BOOL
CloseHandle.argtypes = [HANDLE]
CreateEvent = ctypes.windll.kernel32.CreateEventW
CreateEvent.restype = BOOL
CreateEvent.argtypes = [LPSECURITY_ATTRIBUTES, BOOL, BOOL, LPCWSTR]
WaitForSingleObject = ctypes.windll.kernel32.WaitForSingleObject
WaitForSingleObject.restype = DWORD
WaitForSingleObject.argtypes = [HANDLE, DWORD]
ERROR_SUCCESS = 0x00000000
KEY_READ = 0x00020019
KEY_QUERY_VALUE = 0x00000001
REG_NOTIFY_CHANGE_NAME = 0x00000001
REG_NOTIFY_CHANGE_LAST_SET = 0x00000004
WAIT_OBJECT_0 = 0x00000000
WAIT_TIMEOUT = 0x00000102
class RegistryMonitor:
def __init__(self, root, subkey):
self._root = root
self._subkey = subkey
self._event = CreateEvent(None, False, False, None)
self._key = None
self._open_key()
if self._key:
self._set_key_update_notification()
def close(self):
CloseHandle(self._event)
if self._key:
RegCloseKey(self._key)
self._key = None
def is_updated(self):
wait_result = WaitForSingleObject(self._event, 0)
# previously watched
if wait_result == WAIT_OBJECT_0:
self._set_key_update_notification()
return True
# no changes or no key before
if wait_result != WAIT_TIMEOUT:
# unexpected error
logging.warning("Unexpected WaitForSingleObject result %s", wait_result)
return False
if self._key is None:
self._open_key()
if self._key is not None:
self._set_key_update_notification()
return False
def _set_key_update_notification(self):
filter_ = REG_NOTIFY_CHANGE_NAME | REG_NOTIFY_CHANGE_LAST_SET
status = RegNotifyChangeKeyValue(self._key, True, filter_, self._event, True)
if status != ERROR_SUCCESS:
# key was deleted
RegCloseKey(self._key)
self._key = None
def _open_key(self):
access = KEY_QUERY_VALUE | KEY_READ
self._key = HKEY()
rc = RegOpenKeyEx(self._root, self._subkey, 0, access, ctypes.byref(self._key))
if rc != ERROR_SUCCESS:
self._key = None