win32.py

# Copyright Jonathan Hartley 2013. BSD 3-Clause license, see LICENSE file.

# from winbase.h
STDOUT = -11
STDERR = -12

try:
    import ctypes
    from ctypes import LibraryLoader
    windll = LibraryLoader(ctypes.WinDLL)
    from ctypes import wintypes
except (AttributeError, ImportError):
    windll = None
    SetConsoleTextAttribute = lambda *_: None
    winapi_test = lambda *_: None
else:
    from ctypes import byref, Structure, c_char, POINTER

    COORD = wintypes._COORD

    class CONSOLE_SCREEN_BUFFER_INFO(Structure):
        """struct in wincon.h."""
        _fields_ = [
            ("dwSize", COORD),
            ("dwCursorPosition", COORD),
            ("wAttributes", wintypes.WORD),
            ("srWindow", wintypes.SMALL_RECT),
            ("dwMaximumWindowSize", COORD),
        ]
        def __str__(self):
            return '(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)' % (
                self.dwSize.Y, self.dwSize.X
                , self.dwCursorPosition.Y, self.dwCursorPosition.X
                , self.wAttributes
                , self.srWindow.Top, self.srWindow.Left, self.srWindow.Bottom, self.srWindow.Right
                , self.dwMaximumWindowSize.Y, self.dwMaximumWindowSize.X
            )

    _GetStdHandle = windll.kernel32.GetStdHandle
    _GetStdHandle.argtypes = [
        wintypes.DWORD,
    ]
    _GetStdHandle.restype = wintypes.HANDLE

    _GetConsoleScreenBufferInfo = windll.kernel32.GetConsoleScreenBufferInfo
    _GetConsoleScreenBufferInfo.argtypes = [
        wintypes.HANDLE,
        POINTER(CONSOLE_SCREEN_BUFFER_INFO),
    ]
    _GetConsoleScreenBufferInfo.restype = wintypes.BOOL

    _SetConsoleTextAttribute = windll.kernel32.SetConsoleTextAttribute
    _SetConsoleTextAttribute.argtypes = [
        wintypes.HANDLE,
        wintypes.WORD,
    ]
    _SetConsoleTextAttribute.restype = wintypes.BOOL

    _SetConsoleCursorPosition = windll.kernel32.SetConsoleCursorPosition
    _SetConsoleCursorPosition.argtypes = [
        wintypes.HANDLE,
        COORD,
    ]
    _SetConsoleCursorPosition.restype = wintypes.BOOL

    _FillConsoleOutputCharacterA = windll.kernel32.FillConsoleOutputCharacterA
    _FillConsoleOutputCharacterA.argtypes = [
        wintypes.HANDLE,
        c_char,
        wintypes.DWORD,
        COORD,
        POINTER(wintypes.DWORD),
    ]
    _FillConsoleOutputCharacterA.restype = wintypes.BOOL

    _FillConsoleOutputAttribute = windll.kernel32.FillConsoleOutputAttribute
    _FillConsoleOutputAttribute.argtypes = [
        wintypes.HANDLE,
        wintypes.WORD,
        wintypes.DWORD,
        COORD,
        POINTER(wintypes.DWORD),
    ]
    _FillConsoleOutputAttribute.restype = wintypes.BOOL

    _SetConsoleTitleW = windll.kernel32.SetConsoleTitleA
    _SetConsoleTitleW.argtypes = [
        wintypes.LPCSTR
    ]
    _SetConsoleTitleW.restype = wintypes.BOOL

    handles = {
        STDOUT: _GetStdHandle(STDOUT),
        STDERR: _GetStdHandle(STDERR),
    }

    def winapi_test():
        handle = handles[STDOUT]
        csbi = CONSOLE_SCREEN_BUFFER_INFO()
        success = _GetConsoleScreenBufferInfo(
            handle, byref(csbi))
        return bool(success)

    def GetConsoleScreenBufferInfo(stream_id=STDOUT):
        handle = handles[stream_id]
        csbi = CONSOLE_SCREEN_BUFFER_INFO()
        success = _GetConsoleScreenBufferInfo(
            handle, byref(csbi))
        return csbi

    def SetConsoleTextAttribute(stream_id, attrs):
        handle = handles[stream_id]
        return _SetConsoleTextAttribute(handle, attrs)

    def SetConsoleCursorPosition(stream_id, position, adjust=True):
        position = COORD(*position)
        # If the position is out of range, do nothing.
        if position.Y <= 0 or position.X <= 0:
            return
        # Adjust for Windows' SetConsoleCursorPosition:
        #    1. being 0-based, while ANSI is 1-based.
        #    2. expecting (x,y), while ANSI uses (y,x).
        adjusted_position = COORD(position.Y - 1, position.X - 1)
        if adjust:
            # Adjust for viewport's scroll position
            sr = GetConsoleScreenBufferInfo(STDOUT).srWindow
            adjusted_position.Y += sr.Top
            adjusted_position.X += sr.Left
        # Resume normal processing
        handle = handles[stream_id]
        return _SetConsoleCursorPosition(handle, adjusted_position)

    def FillConsoleOutputCharacter(stream_id, char, length, start):
        handle = handles[stream_id]
        char = c_char(char.encode())
        length = wintypes.DWORD(length)
        num_written = wintypes.DWORD(0)
        # Note that this is hard-coded for ANSI (vs wide) bytes.
        success = _FillConsoleOutputCharacterA(
            handle, char, length, start, byref(num_written))
        return num_written.value

    def FillConsoleOutputAttribute(stream_id, attr, length, start):
        ''' FillConsoleOutputAttribute( hConsole, csbi.wAttributes, dwConSize, coordScreen, &cCharsWritten )'''
        handle = handles[stream_id]
        attribute = wintypes.WORD(attr)
        length = wintypes.DWORD(length)
        num_written = wintypes.DWORD(0)
        # Note that this is hard-coded for ANSI (vs wide) bytes.
        return _FillConsoleOutputAttribute(
            handle, attribute, length, start, byref(num_written))

    def SetConsoleTitle(title):
        return _SetConsoleTitleW(title)