asyncfile.py 文件源码

def pipe(bufsize=8192):
        """Creates overlapped (asynchronous) pipe.
        """
        name = r'\\.\pipe\pycos-pipe-%d-%d' % (os.getpid(), next(_pipe_id))
        openmode = (win32pipe.PIPE_ACCESS_INBOUND | win32file.FILE_FLAG_OVERLAPPED |
                    FILE_FLAG_FIRST_PIPE_INSTANCE)
        pipemode = (win32pipe.PIPE_TYPE_BYTE | win32pipe.PIPE_READMODE_BYTE)
        rh = wh = None
        try:
            rh = win32pipe.CreateNamedPipe(
                name, openmode, pipemode, 1, bufsize, bufsize,
                win32pipe.NMPWAIT_USE_DEFAULT_WAIT, None)

            wh = win32file.CreateFile(
                name, win32file.GENERIC_WRITE | winnt.FILE_READ_ATTRIBUTES, 0, None,
                win32file.OPEN_EXISTING, win32file.FILE_FLAG_OVERLAPPED, None)

            overlapped = pywintypes.OVERLAPPED()
            # 'yield' can't be used in constructor so use sync wait
            # (in this case it is should be okay)
            overlapped.hEvent = win32event.CreateEvent(None, 0, 0, None)
            rc = win32pipe.ConnectNamedPipe(rh, overlapped)
            if rc == winerror.ERROR_PIPE_CONNECTED:
                win32event.SetEvent(overlapped.hEvent)
            rc = win32event.WaitForSingleObject(overlapped.hEvent, 1000)
            overlapped = None
            if rc != win32event.WAIT_OBJECT_0:
                pycos.logger.warning('connect failed: %s' % rc)
                raise Exception(rc)
            return (rh, wh)
        except:
            if rh is not None:
                win32file.CloseHandle(rh)
            if wh is not None:
                win32file.CloseHandle(wh)
            raise