A wrapper over ctypes for the Windows API

wtypes.py

import ctypes as ct
from ctypes.wintypes import *
import uuid

def has_func(ctypes_dll, func_name):
    if hasattr(ctypes_dll, func_name):
        return func_name
    if not func_name.endswith("W") and hasattr(ctypes_dll, func_name + "W"):
        return func_name + "W"
    return None

def declare_func(*args, **kwargs):
    return declare_func2(*args, **kwargs)[0]

def declare_func2(ctypes_dll, func_name, ret=None, arg=[]):
    # do not fail if the function is not supported by the os
    func_name = has_func(ctypes_dll, func_name)
    if not func_name:
        return None, None

    # encapsulated *arg* in a list if needed
    if isinstance(arg, tuple):
        arg = list(arg)
    elif not isinstance(arg, list):
        arg = [arg]

    # declare function in ctypes' namespace
    func = getattr(ctypes_dll, func_name)
    func.argtypes = arg
    if ret is not None:
        func.restype = ret

    return func, func_name

def declare_global_func(*args, **kwargs):
    func, name = declare_func2(*args, **kwargs)
    if func:
        globals()[name] = func
        return func
    return None

def ZeroMemory(ctypes_obj):
    ct.memset(ct.addressof(ctypes_obj), 0, ct.sizeof(ctypes_obj))



LRESULT = LPARAM
LONG_PTR = LPARAM
ULONG_PTR = WPARAM
PVOID = ct.c_void_p

class COPYDATASTRUCT(ct.Structure):
    _fields_ = [("dwData", ULONG_PTR),
                ("cbData", DWORD),
                ("lpData", PVOID)]

class GUID(Structure):
    _fields_ = [
        ("Data1", DWORD),
        ("Data2", WORD),
        ("Data3", WORD),
        ("Data4", BYTE * 8)]

    def __init__(self, uuidstr):
        super().__init__(self)
        (self.Data1, self.Data2, self.Data3, self.Data4[0], self.Data4[1],
            rest) = uuid.UUID(uuidstr).fields
        for i in range(2, 8):
            self.Data4[i] = rest >> (8 - i - 1) * 8 & 0xff

class WNDCLASSEXW(ct.Structure):
    _fields_ = [("cbSize", UINT),
                ("style", UINT),
                ("lpfnWndProc", WNDPROCTYPE),
                ("cbClsExtra", ct.c_int),
                ("cbWndExtra", ct.c_int),
                ("hInstance", HINSTANCE),
                ("hIcon", HICON),
                ("hCursor", HANDLE),
                ("hBrush", HBRUSH),
                ("lpszMenuName", LPCWSTR),
                ("lpszClassName", LPCWSTR),
                ("hIconSm", HICON)]

WNDPROCTYPE = ct.WINFUNCTYPE(LRESULT, HWND, UINT, WPARAM, LPARAM)

WM_QUIT = 0x12
WM_COPYDATA = 0x4A
WM_COMMAND = 0x0111
WM_USER = 0x0400

WAIT_TIMEOUT = 258

GWLP_USERDATA = -21

FOLDERID_AccountPictures = "{008ca0b1-55b4-4c56-b8a8-4de4b299d3be}" # %APPDATA%\Microsoft\Windows\AccountPictures
FOLDERID_CommonStartMenu = "{a4115719-d62e-491d-aa7c-e74b8be3b067}" # %ALLUSERSPROFILE%\Microsoft\Windows\Start Menu
FOLDERID_CommonStartup = "{82a5ea35-d9cd-47c5-9629-e15d2f714e6e}" # %ALLUSERSPROFILE%\Microsoft\Windows\Start Menu\Programs\StartUp
FOLDERID_Desktop = "{b4bfcc3a-db2c-424c-b029-7fe99a87c641}" # %USERPROFILE%\Desktop
FOLDERID_Documents = "{fdd39ad0-238f-46af-adb4-6c85480369c7}" # %USERPROFILE%\Documents
FOLDERID_Downloads = "{374de290-123f-4565-9164-39c4925e467b}" # %USERPROFILE%\Downloads
FOLDERID_LocalAppData = "{f1b32785-6fba-4fcf-9d55-7b8e7f157091}" # %LOCALAPPDATA% (%USERPROFILE%\AppData\Local)
FOLDERID_LocalAppDataLow = "{A520A1A4-1780-4FF6-BD18-167343C5AF16}" # %USERPROFILE%\AppData\LocalLow
FOLDERID_Profile = "{5e6c858f-0e22-4760-9afe-ea3317b67173}" # %USERPROFILE% (%SystemDrive%\Users\%USERNAME%)
FOLDERID_ProgramFiles = "{905e63b6-c1bf-494e-b29c-65b732d3d21a}" # %ProgramFiles%
FOLDERID_ProgramFilesX64 = "{6d809377-6af0-444b-8957-a3773f02200e}" # %ProgramFiles%
FOLDERID_ProgramFilesX86 = "{7c5a40ef-a0fb-4bfc-874a-c0f2e0b9fa8e}" # %ProgramFiles(x86)%
FOLDERID_RoamingAppData = "{3eb685db-65f9-4cf6-a03a-e3ef65729f3d}" # %APPDATA% (%USERPROFILE%\AppData\Roaming)
FOLDERID_StartMenu = "{625b53c3-ab48-4ec1-ba1f-a1ef4146fc19}" # %APPDATA%\Microsoft\Windows\Start Menu
FOLDERID_Startup = "{b97d20bb-f46a-4c97-ba10-5e3608430854}" # %APPDATA%\Microsoft\Windows\Start Menu\Programs\StartUp
FOLDERID_UserProgramFiles = "{5cd7aee2-2219-4a67-b85d-6c9ce15660cb}" # %LOCALAPPDATA%\Programs
FOLDERID_Windows = "{f38bf404-1d43-42f2-9305-67de0b28fc23}" # %windir%


kernel32 = ct.windll.kernel32
user32 = ct.windll.user32
shell32 = ct.windll.shell32



declare_global_func(kernel32, "GetLastError", ret=DWORD)
declare_global_func(kernel32, "GetModuleHandleW", ret=HMODULE, arg=[LPCWSTR])
declare_global_func(kernel32, "SetLastError", arg=[DWORD])

declare_global_func(user32, "ChangeWindowMessageFilterEx", ret=BOOL,
    arg=[HWND, UINT, DWORD, ct.c_void_p])
declare_global_func(user32, "CreateWindowExW", ret=HWND, arg=[
    DWORD, LPCWSTR, LPCWSTR, DWORD, ct.c_int, ct.c_int, ct.c_int, ct.c_int,
    HWND, HANDLE, HINSTANCE, LPVOID])
declare_global_func(user32, "DefWindowProcW", ret=LRESULT,
    arg=[HWND, UINT, WPARAM, LPARAM])
declare_global_func(user32, "DestroyWindow", ret=BOOL, arg=[HWND])
declare_global_func(user32, "DispatchMessageW", ret=LRESULT, arg=[LPMSG])
declare_global_func(user32, "FindWindowW", ret=HWND, arg=[LPCWSTR, LPCWSTR])
declare_global_func(user32, "GetClassInfoExW", ret=BOOL,
    arg=[HANDLE, LPCWSTR, ct.POINTER(WNDCLASSEXW)])
declare_global_func(user32, "GetWindowLongPtrW", ret=LONG_PTR,
    arg=[HWND, ct.c_int])
declare_global_func(user32, "MsgWaitForMultipleObjects", ret=DWORD,
    arg=[DWORD, ct.POINTER(HANDLE), BOOL, DWORD, DWORD])
declare_global_func(user32, "PeekMessageW", ret=BOOL,
    arg=[LPMSG, HWND, UINT, UINT, UINT])
declare_global_func(user32, "RegisterClassExW", ret=ATOM,
    arg=[ct.POINTER(WNDCLASSEXW)])
declare_global_func(user32, "SendMessageW", ret=LRESULT,
    arg=[HWND, UINT, WPARAM, LPARAM])
declare_global_func(user32, "SetWindowLongPtrW", ret=LONG_PTR,
    arg=[HWND, ct.c_int, LONG_PTR])
declare_global_func(user32, "TranslateMessage", ret=BOOL, arg=[LPMSG])

declare_global_func(shell32, "SHGetKnownFolderPath", ret=ct.HRESULT,
    arg=[ct.POINTER(GUID), DWORD, HANDLE, PWSTR])



def get_known_folder_path(known_folder_guidstr):
    guid = GUID(known_folder_guidstr)
    path_ptr = ct.c_wchar_p()
    res = SHGetKnownFolderPath(ct.byref(guid), 0, None, ct.byref(path_ptr))
    if res:
        raise OSError(0, "SHGetKnownFolderPath('{}') failed (code {})".format(known_folder_guidstr, res), None, res)
    return path_ptr.value