src/m_raw_channel.cc

   1 ///
   2 /// \file       m_raw_channel.cc
   3 ///             Mode class for a raw channel
   4 ///
   5
   6 /*
   7     Copyright (C) 2005-2010, Net Direct Inc. (http://www.netdirect.ca/)
   8     Portions Copyright (C) 2010 RealVNC Ltd.
   9
  10     This program is free software; you can redistribute it and/or modify
  11     it under the terms of the GNU General Public License as published by
  12     the Free Software Foundation; either version 2 of the License, or
  13     (at your option) any later version.
  14
  15     This program is distributed in the hope that it will be useful,
  16     but WITHOUT ANY WARRANTY; without even the implied warranty of
  17     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  18
  19     See the GNU General Public License in the COPYING file at the
  20     root directory of this project for more details.
  21 */
  22
  23 #include "m_raw_channel.h"
  24 #include "data.h"
  25 #include "protocol.h"
  26 #include "protostructs.h"
  27 #include "packet.h"
  28 #include "endian.h"
  29 #include "error.h"
  30 #include "usbwrap.h"
  31 #include "controller.h"
  32 #include <stdexcept>
  33 #include <sstream>
  34 #include <cstring>
  35 #include "protostructs.h"
  36
  37 #include "debug.h"
  38
  39 #define RAW_HEADER_SIZE 4
  40
  41 namespace Barry { namespace Mode {
  42
  43 static void HandleReceivedDataCallback(void* ctx, Data* data) {
  44         ((RawChannel*)ctx)->HandleReceivedData(*data);
  45 }
  46
  47 ///////////////////////////////////////////////////////////////////////////////
  48 // RawChannel Mode class
  49
  50 RawChannel::RawChannel(Controller &con, RawChannelDataCallback& callback)
  51         : Mode(con, Controller::RawChannel)
  52         , m_callback(callback)
  53         , m_sendBuffer(0)
  54         , m_zeroRegistered(false)
  55 {
  56         m_sendBuffer = new unsigned char[MAX_PACKET_SIZE];
  57 }
  58
  59 RawChannel::~RawChannel()
  60 {
  61         UnregisterZeroSocketInterest();
  62         delete[] m_sendBuffer;
  63 }
  64
  65 void RawChannel::OnOpen()
  66 {
  67         // Enable sequence packets so that DataSendAck callback and close can be
  68         // implemented
  69         m_zeroRegistered = true;
  70         m_socket->HideSequencePacket(false);
  71         m_con.m_queue->RegisterInterest(0, HandleReceivedDataCallback, this);
  72         m_socket->RegisterInterest(HandleReceivedDataCallback, this);
  73 }
  74
  75 ///////////////////////////////////////////////////////////////////////////////
  76 // public API
  77
  78 void RawChannel::Send(Data& data, int timeout)
  79 {
  80         size_t packetSize = RAW_HEADER_SIZE + data.GetSize();
  81
  82         if( packetSize > MAX_PACKET_SIZE ) {
  83                 throw Barry::Error("RawChannel: send data size larger than MaximumPacketSize");
  84         }
  85
  86         // setup header and copy data in
  87         MAKE_PACKETPTR_BUF(packet, m_sendBuffer);
  88         packet->socket = htobs(m_socket->GetSocket());
  89         packet->size = htobs(packetSize);
  90         std::memcpy(&(m_sendBuffer[RAW_HEADER_SIZE]), data.GetData(), data.GetSize());
  91
  92         Data toSend(m_sendBuffer, packetSize);
  93         m_socket->Send(toSend, timeout);
  94 }
  95
  96 size_t RawChannel::MaximumSendSize()
  97 {
  98         return MAX_PACKET_SIZE - RAW_HEADER_SIZE;
  99 }
 100
 101 void RawChannel::HandleReceivedData(Data& data)
 102 {
 103         Protocol::CheckSize(data, MIN_PACKET_DATA_SIZE);
 104         MAKE_PACKETPTR_BUF(packet, data.GetData());
 105
 106         if( packet->socket == 0 ) {
 107                 switch( btohs(packet->command) )
 108                 {
 109                 case SB_COMMAND_SEQUENCE_HANDSHAKE:
 110                         m_callback.DataSendAck();
 111                         break;
 112                 case SB_COMMAND_CLOSE_SOCKET:
 113                 case SB_COMMAND_REMOTE_CLOSE_SOCKET:
 114                         // Stop listening to socket 0 messages
 115                         // so that socket close work.
 116                         UnregisterZeroSocketInterest();
 117                         m_callback.ChannelClose();
 118                         break;
 119                 default:
 120                         UnregisterZeroSocketInterest();
 121                         m_callback.ChannelError("RawChannel: Got unexpected socket zero packet");
 122                         break;
 123                 }
 124         }
 125         else {
 126                 // Should be a socket packet for us, so remove packet headers
 127                 Data partial(data.GetData() + RAW_HEADER_SIZE, data.GetSize() - RAW_HEADER_SIZE);
 128                 m_callback.DataReceived(partial);
 129         }
 130 }
 131
 132 void RawChannel::UnregisterZeroSocketInterest()
 133 {
 134         if( m_zeroRegistered ) {
 135                 m_con.m_queue->UnregisterInterest(0);
 136                 m_socket->HideSequencePacket(true);
 137                 m_zeroRegistered = false;
 138         }
 139 }
 140
 141 }} // namespace Barry::Mode