aria2/src/LpdMessageDispatcher.cc

/*
 * aria2 - The high speed download utility
 *
 * Copyright (C) 2010 Tatsuhiro Tsujikawa
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 * In addition, as a special exception, the copyright holders give
 * permission to link the code of portions of this program with the
 * OpenSSL library under certain conditions as described in each
 * individual source file, and distribute linked combinations
 * including the two.
 * You must obey the GNU General Public License in all respects
 * for all of the code used other than OpenSSL.  If you modify
 * file(s) with this exception, you may extend this exception to your
 * version of the file(s), but you are not obligated to do so.  If you
 * do not wish to do so, delete this exception statement from your
 * version.  If you delete this exception statement from all source
 * files in the program, then also delete it here.
 */
#include "LpdMessageDispatcher.h"
#include "SocketCore.h"
#include "A2STR.h"
#include "util.h"
#include "Logger.h"
#include "LogFactory.h"
#include "BtConstants.h"
#include "RecoverableException.h"
#include "wallclock.h"
#include "fmt.h"

namespace aria2 {

LpdMessageDispatcher::LpdMessageDispatcher(const std::string& infoHash,
                                           uint16_t port,
                                           const std::string& multicastAddress,
                                           uint16_t multicastPort,
                                           std::chrono::seconds interval)
    : infoHash_(infoHash),
      port_(port),
      multicastAddress_(multicastAddress),
      multicastPort_(multicastPort),
      timer_(Timer::zero()),
      interval_(std::move(interval)),
      request_(bittorrent::createLpdRequest(multicastAddress_, multicastPort_,
                                            infoHash_, port_))
{
}

LpdMessageDispatcher::~LpdMessageDispatcher() {}

bool LpdMessageDispatcher::init(const std::string& localAddr, unsigned char ttl,
                                unsigned char loop)
{
  try {
    socket_ = std::make_shared<SocketCore>(SOCK_DGRAM);
    socket_->create(AF_INET);
    A2_LOG_DEBUG(
        fmt("Setting multicast outgoing interface=%s", localAddr.c_str()));
    socket_->setMulticastInterface(localAddr);
    A2_LOG_DEBUG(
        fmt("Setting multicast ttl=%u", static_cast<unsigned int>(ttl)));
    socket_->setMulticastTtl(ttl);
    A2_LOG_DEBUG(
        fmt("Setting multicast loop=%u", static_cast<unsigned int>(loop)));
    socket_->setMulticastLoop(loop);
    return true;
  }
  catch (RecoverableException& e) {
    A2_LOG_ERROR_EX("Failed to initialize LpdMessageDispatcher.", e);
  }
  return false;
}

bool LpdMessageDispatcher::sendMessage()
{
  return socket_->writeData(request_.c_str(), request_.size(),
                            multicastAddress_,
                            multicastPort_) == (ssize_t)request_.size();
}

bool LpdMessageDispatcher::isAnnounceReady() const
{
  return timer_.difference(global::wallclock()) >= interval_;
}

void LpdMessageDispatcher::resetAnnounceTimer()
{
  timer_ = global::wallclock();
}

namespace bittorrent {

std::string createLpdRequest(const std::string& multicastAddress,
                             uint16_t multicastPort,
                             const std::string& infoHash, uint16_t port)
{
  return fmt("BT-SEARCH * HTTP/1.1\r\n"
             "Host: %s:%u\r\n"
             "Port: %u\r\n"
             "Infohash: %s\r\n"
             "\r\n\r\n",
             multicastAddress.c_str(), multicastPort, port,
             util::toHex(infoHash).c_str());
}

} // namespace bittorrent

} // namespac aria2