src/interest.cpp

/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/**
 * Copyright (c) 2013-2014 Regents of the University of California.
 *
 * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
 *
 * ndn-cxx library is free software: you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later version.
 *
 * ndn-cxx library 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 Lesser General Public License for more details.
 *
 * You should have received copies of the GNU General Public License and GNU Lesser
 * General Public License along with ndn-cxx, e.g., in COPYING.md file.  If not, see
 * <http://www.gnu.org/licenses/>.
 *
 * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
 *
 * Based on code originally written by Jeff Thompson <jefft0@remap.ucla.edu>
 */

#include "common.hpp"

#include "interest.hpp"
#include "util/random.hpp"
#include "data.hpp"

namespace ndn {

uint32_t
Interest::getNonce() const
{
  if (!m_nonce.hasWire())
    const_cast<Interest*>(this)->setNonce(random::generateWord32());

  if (m_nonce.value_size() == sizeof(uint32_t))
    return *reinterpret_cast<const uint32_t*>(m_nonce.value());
  else {
    // for compatibility reasons.  Should be removed eventually
    return readNonNegativeInteger(m_nonce);
  }
}

Interest&
Interest::setNonce(uint32_t nonce)
{
  if (m_wire.hasWire() && m_nonce.value_size() == sizeof(uint32_t)) {
    std::memcpy(const_cast<uint8_t*>(m_nonce.value()), &nonce, sizeof(nonce));
  }
  else {
    m_nonce = dataBlock(Tlv::Nonce,
                        reinterpret_cast<const uint8_t*>(&nonce),
                        sizeof(nonce));
    m_wire.reset();
  }
  return *this;
}

bool
Interest::matchesName(const Name& name) const
{
  if (name.size() < m_name.size())
    return false;

  if (!m_name.isPrefixOf(name))
    return false;

  if (getMinSuffixComponents() >= 0 &&
    // Add 1 for the implicit digest.
      !(name.size() + 1 - m_name.size() >= static_cast<size_t>(getMinSuffixComponents())))
    return false;

  if (getMaxSuffixComponents() >= 0 &&
    // Add 1 for the implicit digest.
      !(name.size() + 1 - m_name.size() <= static_cast<size_t>(getMaxSuffixComponents())))
    return false;

  if (!getExclude().empty() &&
      name.size() > m_name.size() &&
      getExclude().isExcluded(name[m_name.size()]))
    return false;

  return true;
}

bool
Interest::matchesData(const Data& data) const
{
  if (!this->matchesName(data.getName())) {
    return false;
  }

  const KeyLocator& publisherPublicKeyLocator = this->getPublisherPublicKeyLocator();
  if (!publisherPublicKeyLocator.empty()) {
    const Signature& signature = data.getSignature();
    const Block& signatureInfo = signature.getInfo();
    Block::element_const_iterator it = signatureInfo.find(Tlv::KeyLocator);
    if (it == signatureInfo.elements_end()) {
      return false;
    }
    if (publisherPublicKeyLocator.wireEncode() != *it) {
      return false;
    }
  }

  return true;
}

std::ostream&
operator<<(std::ostream& os, const Interest& interest)
{
  os << interest.getName();

  char delim = '?';

  if (interest.getMinSuffixComponents() >= 0) {
    os << delim << "ndn.MinSuffixComponents=" << interest.getMinSuffixComponents();
    delim = '&';
  }
  if (interest.getMaxSuffixComponents() >= 0) {
    os << delim << "ndn.MaxSuffixComponents=" << interest.getMaxSuffixComponents();
    delim = '&';
  }
  if (interest.getChildSelector() >= 0) {
    os << delim << "ndn.ChildSelector=" << interest.getChildSelector();
    delim = '&';
  }
  if (interest.getMustBeFresh()) {
    os << delim << "ndn.MustBeFresh=" << interest.getMustBeFresh();
    delim = '&';
  }
  if (interest.getScope() >= 0) {
    os << delim << "ndn.Scope=" << interest.getScope();
    delim = '&';
  }
  if (interest.getInterestLifetime() >= time::milliseconds::zero()
      && interest.getInterestLifetime() != DEFAULT_INTEREST_LIFETIME) {
    os << delim << "ndn.InterestLifetime=" << interest.getInterestLifetime();
    delim = '&';
  }

  if (interest.hasNonce()) {
    os << delim << "ndn.Nonce=" << interest.getNonce();
    delim = '&';
  }
  if (!interest.getExclude().empty()) {
    os << delim << "ndn.Exclude=" << interest.getExclude();
    delim = '&';
  }

  return os;
}

}