deskflow/src/lib/ipc/IpcClientProxy.cpp

/*
 * synergy -- mouse and keyboard sharing utility
 * Copyright (C) 2012-2016 Symless Ltd.
 * Copyright (C) 2012 Nick Bolton
 *
 * This package is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * found in the file LICENSE that should have accompanied this file.
 *
 * This package is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "ipc/IpcClientProxy.h"

#include "arch/Arch.h"
#include "base/Log.h"
#include "base/TMethodEventJob.h"
#include "io/IStream.h"
#include "ipc/Ipc.h"
#include "ipc/IpcMessage.h"
#include "ipc/IpcSettingMessage.h"
#include "synergy/ProtocolUtil.h"

//
// IpcClientProxy
//

IpcClientProxy::IpcClientProxy(synergy::IStream &stream, IEventQueue *events)
    : m_stream(stream), m_clientType(kIpcClientUnknown), m_disconnecting(false),
      m_readMutex(ARCH->newMutex()), m_writeMutex(ARCH->newMutex()),
      m_events(events) {
  m_events->adoptHandler(
      m_events->forIStream().inputReady(), stream.getEventTarget(),
      new TMethodEventJob<IpcClientProxy>(this, &IpcClientProxy::handleData));

  m_events->adoptHandler(m_events->forIStream().outputError(),
                         stream.getEventTarget(),
                         new TMethodEventJob<IpcClientProxy>(
                             this, &IpcClientProxy::handleWriteError));

  m_events->adoptHandler(m_events->forIStream().inputShutdown(),
                         stream.getEventTarget(),
                         new TMethodEventJob<IpcClientProxy>(
                             this, &IpcClientProxy::handleDisconnect));

  m_events->adoptHandler(m_events->forIStream().outputShutdown(),
                         stream.getEventTarget(),
                         new TMethodEventJob<IpcClientProxy>(
                             this, &IpcClientProxy::handleWriteError));
}

IpcClientProxy::~IpcClientProxy() {
  m_events->removeHandler(m_events->forIStream().inputReady(),
                          m_stream.getEventTarget());
  m_events->removeHandler(m_events->forIStream().outputError(),
                          m_stream.getEventTarget());
  m_events->removeHandler(m_events->forIStream().inputShutdown(),
                          m_stream.getEventTarget());
  m_events->removeHandler(m_events->forIStream().outputShutdown(),
                          m_stream.getEventTarget());

  // don't delete the stream while it's being used.
  ARCH->lockMutex(m_readMutex);
  ARCH->lockMutex(m_writeMutex);
  delete &m_stream;
  ARCH->unlockMutex(m_readMutex);
  ARCH->unlockMutex(m_writeMutex);

  ARCH->closeMutex(m_readMutex);
  ARCH->closeMutex(m_writeMutex);
}

void IpcClientProxy::handleDisconnect(const Event &, void *) {
  disconnect();
  LOG((CLOG_DEBUG "ipc client disconnected"));
}

void IpcClientProxy::handleWriteError(const Event &, void *) {
  disconnect();
  LOG((CLOG_DEBUG "ipc client write error"));
}

void IpcClientProxy::handleData(const Event &, void *) {
  // don't allow the dtor to destroy the stream while we're using it.
  ArchMutexLock lock(m_readMutex);

  LOG((CLOG_DEBUG "start ipc handle data"));

  UInt8 code[4];
  UInt32 n = m_stream.read(code, 4);
  while (n != 0) {

    LOG((CLOG_DEBUG "ipc read: %c%c%c%c", code[0], code[1], code[2], code[3]));

    IpcMessage *m = nullptr;
    if (memcmp(code, kIpcMsgHello, 4) == 0) {
      m = parseHello();
    } else if (memcmp(code, kIpcMsgCommand, 4) == 0) {
      m = parseCommand();
    } else if (memcmp(code, kIpcMsgSetting, 4) == 0) {
      m = parseSetting();
    } else {
      LOG((CLOG_ERR "invalid ipc message"));
      disconnect();
    }

    // don't delete with this event; the data is passed to a new event.
    Event e(m_events->forIpcClientProxy().messageReceived(), this, NULL,
            Event::kDontFreeData);
    e.setDataObject(m);
    m_events->addEvent(e);

    n = m_stream.read(code, 4);
  }

  LOG((CLOG_DEBUG "finished ipc handle data"));
}

void IpcClientProxy::send(const IpcMessage &message) {
  // don't allow other threads to write until we've finished the entire
  // message. stream write is locked, but only for that single write.
  // also, don't allow the dtor to destroy the stream while we're using it.
  ArchMutexLock lock(m_writeMutex);

  LOG((CLOG_DEBUG4 "ipc write: %d", message.type()));

  switch (message.type()) {
  case kIpcLogLine: {
    const IpcLogLineMessage &llm =
        static_cast<const IpcLogLineMessage &>(message);
    const String logLine = llm.logLine();
    ProtocolUtil::writef(&m_stream, kIpcMsgLogLine, &logLine);
    break;
  }

  case kIpcShutdown:
    ProtocolUtil::writef(&m_stream, kIpcMsgShutdown);
    break;

  case kIpcHelloBack:
    ProtocolUtil::writef(&m_stream, kIpcMsgHelloBack);
    break;

  default:
    LOG((CLOG_ERR "ipc message not supported: %d", message.type()));
    break;
  }
}

IpcHelloMessage *IpcClientProxy::parseHello() {
  UInt8 type;
  ProtocolUtil::readf(&m_stream, kIpcMsgHello + 4, &type);

  m_clientType = static_cast<EIpcClientType>(type);

  // must be deleted by event handler.
  return new IpcHelloMessage(m_clientType);
}

IpcCommandMessage *IpcClientProxy::parseCommand() {
  String command;
  UInt8 elevate;
  ProtocolUtil::readf(&m_stream, kIpcMsgCommand + 4, &command, &elevate);

  // must be deleted by event handler.
  return new IpcCommandMessage(command, elevate != 0);
}

IpcSettingMessage *IpcClientProxy::parseSetting() const {
  String name;
  String value;

  ProtocolUtil::readf(&m_stream, kIpcMsgSetting + 4, &name, &value);

  // must be deleted by event handler.
  return new IpcSettingMessage(name, value);
}

void IpcClientProxy::disconnect() {
  LOG((CLOG_DEBUG "ipc disconnect, closing stream"));
  m_disconnecting = true;
  m_stream.close();
  m_events->addEvent(Event(m_events->forIpcClientProxy().disconnected(), this));
}