From f05f52637f32319564a1be9c0564b4fab3e9093b Mon Sep 17 00:00:00 2001 From: Simon Rozman Date: Fri, 8 Feb 2019 14:31:05 +0100 Subject: [PATCH] wintun: Simplify Read method() Signed-off-by: Simon Rozman --- tun/tun_windows.go | 98 +++++++++++++++++++++++----------------------- 1 file changed, 49 insertions(+), 49 deletions(-) diff --git a/tun/tun_windows.go b/tun/tun_windows.go index 906a411..57be3dc 100644 --- a/tun/tun_windows.go +++ b/tun/tun_windows.go @@ -203,64 +203,64 @@ func (tun *nativeTun) Read(buff []byte, offset int) (int, error) { select { case err := <-tun.errors: return 0, err - default: - for { - if tun.rdNextPacket < tun.rdBuff.numPackets { - // Get packet from the queue. - tunPacket := &tun.rdBuff.packets[tun.rdNextPacket] - tun.rdNextPacket++ + } - if packetSizeMax < tunPacket.size { - // Invalid packet size. - continue - } + for { + if tun.rdNextPacket < tun.rdBuff.numPackets { + // Get packet from the queue. + tunPacket := &tun.rdBuff.packets[tun.rdNextPacket] + tun.rdNextPacket++ - // Copy data. - copy(buff[offset:], tunPacket.data[:tunPacket.size]) - return int(tunPacket.size), nil + if packetSizeMax < tunPacket.size { + // Invalid packet size. + continue } - if tun.signals[signalDataAvail] == 0 { - // Data pipe and interface data available event are not open (yet). - err := tun.openTUN() - if err != nil { - return 0, err - } - } + // Copy data. + copy(buff[offset:], tunPacket.data[:tunPacket.size]) + return int(tunPacket.size), nil + } - // Wait for user close or interface data. - r, err := windows.WaitForMultipleObjects(tun.signals[:], false, windows.INFINITE) + if tun.signals[signalDataAvail] == 0 { + // Data pipe and interface data available event are not open (yet). + err := tun.openTUN() if err != nil { - return 0, errors.New("Waiting for data failed: " + err.Error()) - } - switch r { - case windows.WAIT_OBJECT_0 + signalClose, windows.WAIT_ABANDONED + signalClose: - return 0, errors.New("TUN closed") - case windows.WAIT_OBJECT_0 + signalDataAvail: - // Data is available. - case windows.WAIT_ABANDONED + signalDataAvail: - // TUN stopped. Reopen it. - tun.closeTUN() - continue - case windows.WAIT_TIMEOUT: - // Congratulations, we reached infinity. Let's do it again! :) - continue - default: - return 0, errors.New("unexpected result from WaitForMultipleObjects") + return 0, err } + } - // Fill queue. - data := (*[exchangeBufferSize]byte)(unsafe.Pointer(&tun.rdBuff)) - n, err := tun.tunFile.Read(data[:]) - tun.rdNextPacket = 0 - if n != exchangeBufferSize || err != nil { - // TUN interface stopped, returned incomplete data, etc. - // Retry. - tun.rdBuff.numPackets = 0 - tun.closeTUN() - continue - } + // Wait for user close or interface data. + r, err := windows.WaitForMultipleObjects(tun.signals[:], false, windows.INFINITE) + if err != nil { + return 0, errors.New("Waiting for data failed: " + err.Error()) + } + switch r { + case windows.WAIT_OBJECT_0 + signalClose, windows.WAIT_ABANDONED + signalClose: + return 0, errors.New("TUN closed") + case windows.WAIT_OBJECT_0 + signalDataAvail: + // Data is available. + case windows.WAIT_ABANDONED + signalDataAvail: + // TUN stopped. Reopen it. + tun.closeTUN() + continue + case windows.WAIT_TIMEOUT: + // Congratulations, we reached infinity. Let's do it again! :) + continue + default: + return 0, errors.New("unexpected result from WaitForMultipleObjects") + } + + // Fill queue. + data := (*[exchangeBufferSize]byte)(unsafe.Pointer(&tun.rdBuff)) + n, err := tun.tunFile.Read(data[:]) + tun.rdNextPacket = 0 + if n != exchangeBufferSize || err != nil { + // TUN interface stopped, returned incomplete data, etc. + // Retry. + tun.rdBuff.numPackets = 0 + tun.closeTUN() + continue } } }