Python checks.error_check函数代码示例

def WaitForSingleObject(hHandle, dwMilliseconds):
    """
    Waits for the specified object to be in a signaled state
    or for ``dwMiliseconds`` to elapse.

    .. seealso::

        https://msdn.microsoft.com/en-us/library/ms687032

    :param pywincffi.wintypes.HANDLE hHandle:
        The handle to wait on.

    :param int dwMilliseconds:
        The time-out interval.
    """
    input_check("hHandle", hHandle, HANDLE)
    input_check("dwMilliseconds", dwMilliseconds, integer_types)

    ffi, library = dist.load()
    result = library.WaitForSingleObject(
        wintype_to_cdata(hHandle), ffi.cast("DWORD", dwMilliseconds)
    )

    if result == library.WAIT_FAILED:
        raise WindowsAPIError(
            "WaitForSingleObject", "Wait Failed", ffi.getwinerror()[-1],
            return_code=result, expected_return_code="not %s" % result)

    error_check("WaitForSingleObject")

    return result

def SetConsoleTextAttribute(hConsoleOutput, wAttributes):
    """
    Sets the attributes of characters written to a console buffer.

    .. seealso::

        https://docs.microsoft.com/en-us/windows/console/setconsoletextattribute

    :param pywincffi.wintypes.HANDLE hConsoleOutput:
        A handle to the console screen buffer. The handle must have the
        ``GENERIC_READ`` access right.

    :param int wAttributes:
        The character attribute(s) to set.
    """
    input_check("hConsoleOutput", hConsoleOutput, HANDLE)
    input_check("wAttributes", wAttributes, integer_types)
    ffi, library = dist.load()
    # raise Exception(type(wAttributes))
    # info = ffi.new("PCHAR_INFO")
    code = library.SetConsoleTextAttribute(
        wintype_to_cdata(hConsoleOutput),
        ffi.cast("ATOM", wAttributes)
    )
    error_check("SetConsoleTextAttribute", code=code, expected=NON_ZERO)

def OpenEvent(dwDesiredAccess, bInheritHandle, lpName):
    """
    Opens an existing named event.

    .. seealso::

        https://msdn.microsoft.com/en-us/library/ms684305

    :param int dwDesiredAccess:
        The access desired for the event object.

    :param bool bInheritHandle:
    :param str lpName:
        Type is ``unicode`` on Python 2, ``str`` on Python 3.

    :return:
        Returns a :class:`pywincffi.wintypes.HANDLE` to the event.
    """
    input_check("dwDesiredAccess", dwDesiredAccess, integer_types)
    input_check("bInheritHandle", bInheritHandle, bool)
    input_check("lpName", lpName, text_type)

    ffi, library = dist.load()

    handle = library.OpenEvent(
        ffi.cast("DWORD", dwDesiredAccess),
        ffi.cast("BOOL", bInheritHandle),
        lpName
    )
    error_check("OpenEvent")
    return HANDLE(handle)

def ClearCommError(hFile):
    """
    Retrieves information about a communications error and reports the
    current status of a communications device.

    .. seealso::

        https://msdn.microsoft.com/en-us/aa363180

    :param pywincffi.wintypes.HANDLE hFile:
        A handle to the communications device, typically created by
        :func:`CreateFile`

    :rtype: tuple
    :return:
        Returns a two element tuple containing the ``lpErrors`` and
        ``lpStat`` result objects.

            * ``lpErrors`` - Contains the mast indicating the type of error
            * ``lpStat`` - A ``COMSTAT`` structure which contains the device's
               information.
    """
    input_check("hFile", hFile, HANDLE)

    ffi, library = dist.load()

    lpErrors = ffi.new("LPDWORD")
    lpStat = ffi.new("LPCOMSTAT")
    code = library.ClearCommError(wintype_to_cdata(hFile), lpErrors, lpStat)
    error_check("ClearCommError", code=code, expected=Enums.NON_ZERO)

    # TODO: Build Python instance of COMSTAT here!
    return lpErrors, lpStat

def GetExitCodeProcess(hProcess):
    """
    Retrieves the exit code of the given process handle.  To retrieve
    a process handle use :func:`OpenProcess`.

    .. warning::

        You may want to use :func:`process_exit_code` instead of this
        function if you're just checking to see if a process has
        exited at all.

    .. seealso::

        https://msdn.microsoft.com/en-us/library/ms683189

    :param pywincffi.wintypes.HANDLE hProcess:
        The handle of the process to retrieve the exit code for.

    :returns:
        Returns the exit code of the requested process if one
        can be found.
    """
    input_check("hProcess", hProcess, HANDLE)

    ffi, library = dist.load()
    lpExitCode = ffi.new("LPDWORD")
    code = library.GetExitCodeProcess(wintype_to_cdata(hProcess), lpExitCode)
    error_check("GetExitCodeProcess", code=code, expected=Enums.NON_ZERO)
    return lpExitCode[0]

def CreateEvent(
        bManualReset, bInitialState, lpEventAttributes=None, lpName=None):
    """
    Creates or opens an named or unnamed event object.

    .. seealso::

        https://msdn.microsoft.com/en-us/library/ms682396

    :param bool bManualReset:
        If True then this function will create a manual reset
        event which must be manually reset with :func:`ResetEvent`.  Refer
        to the msdn documentation for full information.

    :param bool bInitialState:
        If True the initial state will be 'signaled'.

    :keyword :class:`pywincffi.wintypes.SECURITY_ATTRIBUTES` lpEventAttributes:
        If not provided then, by default, the handle cannot be inherited
        by a subprocess.

    :keyword str lpName:
        Type is ``unicode`` on Python 2, ``str`` on Python 3.
        The optional case-sensitive name of the event.  If not provided then
        the event will be created without an explicit name.

    :returns:
        Returns a :class:`pywincffi.wintypes.HANDLE` to the event. If an event
        by the given name already exists then it will be returned instead of
        creating a new event.
    """
    input_check("bManualReset", bManualReset, bool)
    input_check("bInitialState", bInitialState, bool)

    ffi, library = dist.load()

    if lpName is None:
        lpName = ffi.NULL
    else:
        input_check("lpName", lpName, text_type)

    input_check(
        "lpEventAttributes", lpEventAttributes,
        allowed_types=(SECURITY_ATTRIBUTES, NoneType)
    )

    handle = library.CreateEvent(
        wintype_to_cdata(lpEventAttributes),
        ffi.cast("BOOL", bManualReset),
        ffi.cast("BOOL", bInitialState),
        lpName
    )

    try:
        error_check("CreateEvent")
    except WindowsAPIError as error:
        if error.errno != library.ERROR_ALREADY_EXISTS:
            raise

    return HANDLE(handle)

def OpenProcess(dwDesiredAccess, bInheritHandle, dwProcessId):
    """
    Opens an existing local process object.

    .. seealso::

        https://msdn.microsoft.com/en-us/library/ms684320

    :param int dwDesiredAccess:
        The required access to the process object.

    :param bool bInheritHandle:
        Enables or disable handle inheritance for child processes.

    :param int dwProcessId:
        The id of the local process to be opened.

    :returns:
        Returns a :class:`pywincffi.wintypes.HANDLE` to the opened process.
        This value can be used by other functions such as
        :func:`TerminateProcess`.
    """
    input_check("dwDesiredAccess", dwDesiredAccess, integer_types)
    input_check("bInheritHandle", bInheritHandle, bool)
    input_check("dwProcessId", dwProcessId, integer_types)
    ffi, library = dist.load()

    handle = library.OpenProcess(
        ffi.cast("DWORD", dwDesiredAccess),
        ffi.cast("BOOL", bInheritHandle),
        ffi.cast("DWORD", dwProcessId)
    )
    error_check("OpenProcess")
    return HANDLE(handle)

def SetHandleInformation(hObject, dwMask, dwFlags):
    """
    Sets properties of an object handle.

    .. seealso::

        https://msdn.microsoft.com/en-us/ms724935

    :param pywincffi.wintypes.HANDLE hObject:
        A handle to an object whose information is to be set.

    :param int dwMask:
        A mask that specifies the bit flags to be changed.

    :param int dwFlags:
        Set of bit flags that specifies properties of ``hObject``.
    """
    input_check("hObject", hObject, HANDLE)
    input_check("dwMask", dwMask, integer_types)
    input_check("dwFlags", dwFlags, integer_types)
    ffi, library = dist.load()

    code = library.SetHandleInformation(
        wintype_to_cdata(hObject),
        ffi.cast("DWORD", dwMask),
        ffi.cast("DWORD", dwFlags)
    )
    error_check("SetHandleInformation", code=code, expected=Enums.NON_ZERO)

def WriteFile(hFile, lpBuffer, nNumberOfBytesToWrite=None, lpOverlapped=None):
    """
    Writes data to ``hFile`` which may be an I/O device for file.

    .. seealso::

        https://msdn.microsoft.com/en-us/library/aa365747

    :param pywincffi.wintypes.HANDLE hFile:
        The handle to write to.

    :type lpBuffer: str/bytes
    :param lpBuffer:
        Type is ``str`` on Python 2, ``bytes`` on Python 3.
        The data to be written to the file or device.

    :keyword int nNumberOfBytesToWrite:
        The number of bytes to be written.  Defaults to len(lpBuffer).

    :keyword pywincffi.wintypes.OVERLAPPED lpOverlapped:
        See Microsoft's documentation for intended usage and below for
        an example.

        >>> from pywincffi.core import dist
        >>> from pywincffi.kernel32 import WriteFile, CreateEvent
        >>> from pywincffi.wintypes import OVERLAPPED
        >>> hEvent = CreateEvent(...)
        >>> lpOverlapped = OVERLAPPED()
        >>> lpOverlapped.hEvent = hEvent
        >>> bytes_written = WriteFile(
        ...     hFile, "Hello world", lpOverlapped=lpOverlapped)

    :returns:
        Returns the number of bytes written.
    """
    ffi, library = dist.load()

    input_check("hFile", hFile, HANDLE)
    input_check("lpBuffer", lpBuffer, binary_type)
    input_check(
        "lpOverlapped", lpOverlapped,
        allowed_types=(NoneType, OVERLAPPED)
    )

    if nNumberOfBytesToWrite is None:
        nNumberOfBytesToWrite = len(lpBuffer)
    else:
        input_check(
            "nNumberOfBytesToWrite", nNumberOfBytesToWrite,
            integer_types
        )

    bytes_written = ffi.new("LPDWORD")
    code = library.WriteFile(
        wintype_to_cdata(hFile), lpBuffer, nNumberOfBytesToWrite,
        bytes_written, wintype_to_cdata(lpOverlapped)
    )
    error_check("WriteFile", code=code, expected=Enums.NON_ZERO)

    return bytes_written[0]

def LockFileEx(
        hFile, dwFlags, nNumberOfBytesToLockLow, nNumberOfBytesToLockHigh,
        lpOverlapped=None):
    """
    Locks ``hFile`` for exclusive access by the calling process.

    .. seealso::

        https://msdn.microsoft.com/en-us/library/aa365203

    :param pywincffi.wintypes.HANDLE hFile:
        The handle to the file to lock.  This handle must have been
        created with either the ``GENERIC_READ`` or ``GENERIC_WRITE``
        right.

    :param int dwFlags:
        One or more of the following flags:

            * ``LOCKFILE_EXCLUSIVE_LOCK`` - Request an exclusive lock.
            * ``LOCKFILE_FAIL_IMMEDIATELY`` - Return immediately if the lock
              could not be acquired.  Otherwise :func:`LockFileEx` will wait.

    :param int nNumberOfBytesToLockLow:
        The start of the byte range to lock.

    :param int nNumberOfBytesToLockHigh:
        The end of the byte range to lock.

    :keyword pywincffi.wintypes.OVERLAPPED lpOverlapped:
        The underlying Windows API requires lpOverlapped, which acts both
        an input argument and may contain results after calling. If None is
        provided, a throw-away zero-filled instance will be created to
        support such call. See Microsoft's documentation for intended usage.
    """
    input_check("hFile", hFile, HANDLE)
    input_check("dwFlags", dwFlags, integer_types)
    input_check(
        "nNumberOfBytesToLockLow", nNumberOfBytesToLockLow, integer_types)
    input_check(
        "nNumberOfBytesToLockHigh", nNumberOfBytesToLockHigh, integer_types)

    ffi, library = dist.load()

    if lpOverlapped is None:
        # Required by Windows API, create a throw-away zero-filled instance.
        lpOverlapped = OVERLAPPED()
    else:
        input_check("lpOverlapped", lpOverlapped, allowed_types=OVERLAPPED)

    code = library.LockFileEx(
        wintype_to_cdata(hFile),
        ffi.cast("DWORD", dwFlags),
        ffi.cast("DWORD", 0),  # "_Reserveved_"
        ffi.cast("DWORD", nNumberOfBytesToLockLow),
        ffi.cast("DWORD", nNumberOfBytesToLockHigh),
        wintype_to_cdata(lpOverlapped)
    )
    error_check("LockFileEx", code=code, expected=NON_ZERO)

def UnlockFileEx(
        hFile, nNumberOfBytesToUnlockLow, nNumberOfBytesToUnlockHigh,
        lpOverlapped=None):
    """
    Unlocks a region in the specified file.

    .. seealso::

        https://msdn.microsoft.com/en-us/library/aa365716

    :param pywincffi.wintypes.HANDLE hFile:
        The handle to the file to unlock.  This handle must have been
        created with either the ``GENERIC_READ`` or ``GENERIC_WRITE``
        right.

    :param int nNumberOfBytesToUnlockLow:
        The start of the byte range to unlock.

    :param int nNumberOfBytesToUnlockHigh:
        The end of the byte range to unlock.

    :keyword pywincffi.wintypes.OVERLAPPED lpOverlapped:
        The underlying Windows API requires lpOverlapped, which acts both
        an input argument and may contain results after calling. If None is
        provided, a throw-away zero-filled instance will be created to
        support such call. See Microsoft's documentation for intended usage.
    """
    input_check("hFile", hFile, HANDLE)
    input_check(
        "nNumberOfBytesToUnlockLow",
        nNumberOfBytesToUnlockLow, integer_types)
    input_check(
        "nNumberOfBytesToUnlockHigh",
        nNumberOfBytesToUnlockHigh, integer_types)

    ffi, library = dist.load()

    if lpOverlapped is None:
        # Required by Windows API, create a throw-away zero-filled instance.
        lpOverlapped = OVERLAPPED()
    else:
        input_check("lpOverlapped", lpOverlapped, allowed_types=OVERLAPPED)

    code = library.UnlockFileEx(
        wintype_to_cdata(hFile),
        ffi.cast("DWORD", 0),  # "_Reserveved_"
        ffi.cast("DWORD", nNumberOfBytesToUnlockLow),
        ffi.cast("DWORD", nNumberOfBytesToUnlockHigh),
        wintype_to_cdata(lpOverlapped)
    )
    error_check("UnlockFileEx", code=code, expected=NON_ZERO)

def FlushFileBuffers(hFile):
    """
    Flushes the buffer of the specified file to disk.

    .. seealso::

        https://msdn.microsoft.com/en-us/library/aa364439

    :param pywincffi.wintypes.HANDLE hFile:
        The handle to flush to disk.
    """
    input_check("hFile", hFile, HANDLE)
    _, library = dist.load()
    code = library.FlushFileBuffers(wintype_to_cdata(hFile))
    error_check("FlushFileBuffers", code=code, expected=NON_ZERO)

def ReadFile(hFile, nNumberOfBytesToRead, lpOverlapped=None):
    """
    Read the specified number of bytes from ``hFile``.

    .. seealso::

        https://msdn.microsoft.com/en-us/library/aa365467

    :param pywincffi.wintypes.HANDLE hFile:
        The handle to read from.

    :param int nNumberOfBytesToRead:
        The number of bytes to read from ``hFile``

    :keyword pywincffi.wintypes.OVERLAPPED lpOverlapped:
        See Microsoft's documentation for intended usage and below for
        an example.

        >>> from pywincffi.core import dist
        >>> from pywincffi.kernel32 import ReadFile, CreateEvent
        >>> from pywincffi.wintypes import OVERLAPPED
        >>> hEvent = CreateEvent(...)
        >>> lpOverlapped = OVERLAPPED()
        >>> lpOverlapped.hEvent = hEvent
        >>> read_data = ReadFile(  # read 12 bytes from hFile
        ...     hFile, 12, lpOverlapped=lpOverlapped)

    :returns:
        Returns the binary data read from ``hFile``
        Type is ``str`` on Python 2, ``bytes`` on Python 3.
    """
    ffi, library = dist.load()

    input_check("hFile", hFile, HANDLE)
    input_check("nNumberOfBytesToRead", nNumberOfBytesToRead, integer_types)
    input_check(
        "lpOverlapped", lpOverlapped,
        allowed_types=(NoneType, OVERLAPPED)
    )

    lpBuffer = ffi.new("char []", nNumberOfBytesToRead)
    bytes_read = ffi.new("LPDWORD")
    code = library.ReadFile(
        wintype_to_cdata(hFile), lpBuffer, nNumberOfBytesToRead, bytes_read,
        wintype_to_cdata(lpOverlapped)
    )
    error_check("ReadFile", code=code, expected=NON_ZERO)
    return ffi.unpack(lpBuffer, bytes_read[0])

def CreatePipe(nSize=0, lpPipeAttributes=None):
    """
    Creates an anonymous pipe and returns the read and write handles.

    .. seealso::

        https://msdn.microsoft.com/en-us/library/aa365152
        https://msdn.microsoft.com/en-us/library/aa379560

    >>> from pywincffi.core import dist
    >>> from pywincffi.kernel32 import CreatePipe
    >>> from pywincffi.wintypes import SECURITY_ATTRIBUTES
    >>> lpPipeAttributes = SECURITY_ATTRIBUTES()
    >>> lpPipeAttributes.bInheritHandle = True
    >>> reader, writer = CreatePipe(lpPipeAttributes=lpPipeAttributes)

    :keyword int nSize:
        The size of the buffer in bytes.  Passing in 0, which is the default
        will cause the system to use the default buffer size.

    :keyword pywincffi.wintypes.SECURITY_ATTRIBUTES lpPipeAttributes:
        The security attributes to apply to the handle. By default
        ``NULL`` will be passed in, meaning the handle we create
        cannot be inherited.  For more detailed information see the links
        below.

    :return:
        Returns a tuple of :class:`pywincffi.wintype.HANDLE` containing the
        reader and writer ends of the pipe that was created.  The user of this
        function is responsible for calling CloseHandle at some point.
    """
    input_check("nSize", nSize, integer_types)
    input_check(
        "lpPipeAttributes", lpPipeAttributes,
        allowed_types=(NoneType, SECURITY_ATTRIBUTES)
    )
    lpPipeAttributes = wintype_to_cdata(lpPipeAttributes)

    ffi, library = dist.load()

    hReadPipe = ffi.new("PHANDLE")
    hWritePipe = ffi.new("PHANDLE")

    code = library.CreatePipe(hReadPipe, hWritePipe, lpPipeAttributes, nSize)
    error_check("CreatePipe", code=code, expected=Enums.NON_ZERO)

    return HANDLE(hReadPipe[0]), HANDLE(hWritePipe[0])

def ResetEvent(hEvent):
    """
    Sets the specified event object to the nonsignaled state.

    .. seealso::

        https://msdn.microsoft.com/en-us/library/ms684305

    :param pywincffi.wintypes.HANDLE hEvent:
        A handle to the event object to be reset. The handle must
        have the ``EVENT_MODIFY_STATE`` access right.
    """
    input_check("hEvent", hEvent, HANDLE)

    _, library = dist.load()
    code = library.ResetEvent(wintype_to_cdata(hEvent))
    error_check("ResetEvent", code=code, expected=Enums.NON_ZERO)