func()

in file.go [177:220]

• 36 lines of code
• 11 McCabe index (conditional complexity)

func (f *win32File) asyncIo(c *ioOperation, d *deadlineHandler, bytes uint32, err error) (int, error) {
	if err != syscall.ERROR_IO_PENDING {
		return int(bytes), err
	}

	if f.closing.isSet() {
		cancelIoEx(f.handle, &c.o)
	}

	var timeout timeoutChan
	if d != nil {
		d.channelLock.Lock()
		timeout = d.channel
		d.channelLock.Unlock()
	}

	var r ioResult
	select {
	case r = <-c.ch:
		err = r.err
		if err == syscall.ERROR_OPERATION_ABORTED {
			if f.closing.isSet() {
				err = ErrFileClosed
			}
		} else if err != nil && f.socket {
			// err is from Win32. Query the overlapped structure to get the winsock error.
			var bytes, flags uint32
			err = wsaGetOverlappedResult(f.handle, &c.o, &bytes, false, &flags)
		}
	case <-timeout:
		cancelIoEx(f.handle, &c.o)
		r = <-c.ch
		err = r.err
		if err == syscall.ERROR_OPERATION_ABORTED {
			err = ErrTimeout
		}
	}

	// runtime.KeepAlive is needed, as c is passed via native
	// code to ioCompletionProcessor, c must remain alive
	// until the channel read is complete.
	runtime.KeepAlive(c)
	return int(r.bytes), err
}