Use ctypes to call WIndows API

win_api_test.py

#!/usr/bin/env python3
# _*_ coding:utf-8 _*_

import ctypes
import os
from ctypes import windll, wintypes
from typing import Optional

NULL: int = 0

GENERIC_ALL: int = 28
GENERIC_EXECUTE: int = 29
GENERIC_WRITE: int = 30
GENERIC_READ: int = 31

FILE_SHARE_DISABLE: int = 0x00000000
FILE_SHARE_READ: int = 0x00000001
FILE_SHARE_WRITE: int = 0x00000002
FILE_SHARE_DELETE: int = 0x00000004

CREATE_NEW: int = 1
CREATE_ALWAYS: int = 2
OPEN_EXISTING: int = 3
OPEN_ALWAYS: int = 4
TRUNCATE_EXISTING: int = 5

FILE_ATTRIBUTE_READONLY: int = 0x1
FILE_ATTRIBUTE_HIDDEN: int = 0x2
FILE_ATTRIBUTE_SYSTEM: int = 0x4
FILE_ATTRIBUTE_DIRECTORY: int = 0x10
FILE_ATTRIBUTE_ARCHIVE: int = 0x20
FILE_ATTRIBUTE_DEVICE: int = 0x40
FILE_ATTRIBUTE_NORMAL: int = 0x80
FILE_ATTRIBUTE_TEMPORARY: int = 0x100
FILE_ATTRIBUTE_SPARSE_FILE: int = 0x200
FILE_ATTRIBUTE_REPARSE_POINT: int = 0x400
FILE_ATTRIBUTE_COMPRESSED: int = 0x800
FILE_ATTRIBUTE_OFFLINE: int = 0x1000
FILE_ATTRIBUTE_NOT_CONTENT_INDEXED: int = 0x2000
FILE_ATTRIBUTE_ENCRYPTED: int = 0x4000
FILE_ATTRIBUTE_INTEGRITY_STREAM: int = 0x8000
FILE_ATTRIBUTE_VIRTUAL: int = 0x10000
FILE_ATTRIBUTE_NO_SCRUB_DATA: int = 0x20000
FILE_ATTRIBUTE_RECALL_ON_OPEN: int = 0x40000
FILE_ATTRIBUTE_RECALL_ON_DATA_ACCESS: int = 0x400000

FILE_FLAG_BACKUP_SEMANTICS: int = 0x02000000
FILE_FLAG_DELETE_ON_CLOSE: int = 0x04000000
FILE_FLAG_NO_BUFFERING: int = 0x20000000
FILE_FLAG_OPEN_NO_RECALL: int = 0x00100000
FILE_FLAG_OPEN_REPARSE_POINT: int = 0x00200000
FILE_FLAG_OVERLAPPED: int = 0x40000000
FILE_FLAG_POSIX_SEMANTICS: int = 0x0100000
FILE_FLAG_RANDOM_ACCESS: int = 0x10000000
FILE_FLAG_SESSION_AWARE: int = 0x00800000
FILE_FLAG_SEQUENTIAL_SCAN: int = 0x08000000
FILE_FLAG_WRITE_THROUGH: int = 0x80000000


# ref: https://docs.microsoft.com/en-us/previous-versions/windows/desktop/legacy/aa379560(v=vs.85)
class SECURITY_ATTRIBUTES(ctypes.Structure):
    _fields_ = [
        ("nLength", wintypes.DWORD),
        ("lpSecurityDescriptor", wintypes.LPVOID),
        ("bInheritHandle", wintypes.BOOL)
    ]


# ref: https://docs.microsoft.com/en-us/windows/win32/api/winnt/ns-winnt-large_integer-r1
class LARGE_INTEGER(ctypes.Structure):
    _fields_ = [
        ("QuadPart", ctypes.c_longlong)
    ]


# ref: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilew
def create_file(
    path: str,
    access: int=GENERIC_READ,
    share_mode: int=FILE_SHARE_DISABLE,
    security_attrs: Optional[SECURITY_ATTRIBUTES]=None,
    creation: int=OPEN_EXISTING,
    flags: int=FILE_ATTRIBUTE_NORMAL,
    template: Optional[wintypes.HANDLE]=None,
) -> wintypes.HANDLE:
    CreateFileW = windll.kernel32.CreateFileW
    CreateFileW.argtypes = (
        wintypes.LPCWSTR,  # LPCWSTR               lpFileName
        wintypes.DWORD,    # DWORD                 dwDesiredAccess
        wintypes.DWORD,    # DWORD                 dwShareMode
        wintypes.LPVOID,   # LPSECURITY_ATTRIBUTES lpSecurityAttributes
        wintypes.DWORD,    # DWORD                 dwCreationDisposition
        wintypes.DWORD,    # DWORD                 dwFlagsAndAttributes
        wintypes.HANDLE,   # HANDLE                hTemplateFile
    )
    CreateFileW.restype = wintypes.HANDLE

    # these two arguments below have not been testing.
    lpSecurityAttributes = ctypes.byref(security_attrs) if security_attrs else NULL
    hTemplateFile = template if template else NULL

    return CreateFileW(
        path, access, share_mode, lpSecurityAttributes,
        creation, flags, hTemplateFile
    )


# ref: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getfilesizeex
def get_file_size(path: str) -> int:
    GetFileSizeEx = windll.kernel32.GetFileSizeEx
    GetFileSizeEx.argtypes = (
        wintypes.HANDLE,                # HANDLE         hFile
        ctypes.POINTER(LARGE_INTEGER),  # PLARGE_INTEGER lpFileSize
    )
    GetFileSizeEx.restype = wintypes.BOOL

    size = LARGE_INTEGER(0)
    handle = create_file(path)
    result = GetFileSizeEx(handle, ctypes.byref(size))
    close_handle(handle)
    if not result:
        raise ctypes.WinError()

    return size.QuadPart


# ref: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-gettemppathw
def get_temp_path(max_size: Optional[int]=None) -> str:
    GetTempPathW = windll.kernel32.GetTempPathW
    GetTempPathW.argtypes = (
        wintypes.DWORD,   # DWORD  nBufferLength
        wintypes.LPWSTR,  # LPWSTR lpBuffer
    )
    GetTempPathW.restype = wintypes.DWORD  # zero for failure

    if not max_size:
        max_size = wintypes.MAX_PATH

    buffer = ctypes.create_unicode_buffer(max_size)
    lpBuffer = ctypes.cast(ctypes.byref(buffer), wintypes.LPWSTR)
    result = GetTempPathW(max_size, lpBuffer)
    if result == 0:
        raise ctypes.WinError()

    return buffer.value.rstrip()


# ref: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-gettempfilenamew
def get_temp_file_name(
    parent_path: str=".",
    prefix: Optional[str]=None,
    unique: Optional[int]=0
) -> str:
    GetTempFileNameW = windll.kernel32.GetTempFileNameW
    GetTempFileNameW.argtypes = (
        wintypes.LPCWSTR,  # LPCWSTR lpPathName
        wintypes.LPCWSTR,  # LPCWSTR lpPrefixString
        wintypes.UINT,     # UINT    uUnique
        wintypes.LPWSTR,   # LPWSTR  lpTempFileName
    )
    GetTempFileNameW.restype = wintypes.UINT  # zero for failure

    buffer = ctypes.create_unicode_buffer(wintypes.MAX_PATH)
    lpTempFileName = ctypes.cast(ctypes.byref(buffer), wintypes.LPWSTR)
    result = GetTempFileNameW(parent_path, prefix, unique, lpTempFileName)
    if result == 0:
        raise ctypes.WinError()

    return buffer.value.rstrip()


# ref: https://docs.microsoft.com/en-us/windows/win32/api/handleapi/nf-handleapi-closehandle
def close_handle(handle: wintypes.HANDLE) -> bool:
    CloseHandle = windll.kernel32.CloseHandle
    CloseHandle.argtypes = (wintypes.HANDLE,)
    CloseHandle.restype = wintypes.BOOL

    result = CloseHandle(handle)
    if not result:
        raise ctypes.WinError()

    return True


def print_file_size(path: str) -> None:
    print(f"The size of {path}:")
    print(f"\tvia ctypes module: {get_file_size(path)}")
    print(f"\tvia os module: {os.path.getsize(path)}")
    print()


def main():
    import tempfile

    temp_dir: str = get_temp_path()
    temp_file: str = get_temp_file_name(temp_dir, prefix="win")
    path = os.path.abspath(temp_file)
    with open(path, "wb") as f:
        f.write(os.urandom(1024))

    print("File generated by Win32 API.")
    print_file_size(path)

    temp_dir: str = tempfile.gettempdir()
    file_descriptor: int
    path: str
    file_descriptor, path = tempfile.mkstemp(prefix="tempfile", dir=temp_dir)
    with os.fdopen(file_descriptor, mode="wb") as f:
        f.write(os.urandom(1024))

    print("File generated by Python tempfile module.")
    print_file_size(path)


if __name__ == '__main__':
    main()