Adding .torrent-file class implementation
Change-Id: Ib3b392627ecc4e46cde3f8eb9a11dc192fa5ef3f
Refs: #3433
diff --git a/src/torrent-file.cpp b/src/torrent-file.cpp
new file mode 100644
index 0000000..4302b53
--- /dev/null
+++ b/src/torrent-file.cpp
@@ -0,0 +1,241 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+* Copyright (c) 2016 Regents of the University of California.
+*
+* This file is part of the nTorrent codebase.
+*
+* nTorrent 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.
+*
+* nTorrent 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 nTorrent, e.g., in COPYING.md file. If not, see
+* <http://www.gnu.org/licenses/>.
+*
+* See AUTHORS for complete list of nTorrent authors and contributors.
+*/
+
+#include "torrent-file.hpp"
+
+#include <algorithm>
+
+#include <boost/range/adaptors.hpp>
+
+namespace ndn {
+
+namespace ntorrent {
+
+BOOST_CONCEPT_ASSERT((WireEncodable<TorrentFile>));
+BOOST_CONCEPT_ASSERT((WireDecodable<TorrentFile>));
+static_assert(std::is_base_of<Data::Error, TorrentFile::Error>::value,
+ "TorrentFile::Error should inherit from Data::Error");
+
+TorrentFile::TorrentFile(const Name& torrentFileName,
+ const Name& torrentFilePtr,
+ const Name& commonPrefix,
+ const std::vector<ndn::Name>& catalog)
+ : Data(torrentFileName)
+ , m_commonPrefix(commonPrefix)
+ , m_torrentFilePtr(torrentFilePtr)
+ , m_catalog(catalog)
+{
+}
+
+TorrentFile::TorrentFile(const Name& torrentFileName,
+ const Name& commonPrefix,
+ const std::vector<ndn::Name>& catalog)
+ : Data(torrentFileName)
+ , m_commonPrefix(commonPrefix)
+ , m_catalog(catalog)
+{
+}
+
+TorrentFile::TorrentFile(const Block& block)
+{
+ this->wireDecode(block);
+}
+
+const Name&
+TorrentFile::getName() const
+{
+ return Data::getName();
+}
+
+const Name&
+TorrentFile::getCommonPrefix() const
+{
+ return m_commonPrefix;
+}
+
+void
+TorrentFile::createSuffixCatalog()
+{
+ for (auto i = m_catalog.begin() ; i != m_catalog.end(); ++i) {
+ m_suffixCatalog.push_back((*i).getSubName(m_commonPrefix.size()));
+ }
+}
+
+shared_ptr<Name>
+TorrentFile::getTorrentFilePtr() const
+{
+ if (this->hasTorrentFilePtr()) {
+ return make_shared<Name>(m_torrentFilePtr);
+ }
+ return nullptr;
+}
+
+void
+TorrentFile::constructLongNames()
+{
+ for (auto i = m_suffixCatalog.begin(); i != m_suffixCatalog.end(); ++i) {
+ Name commonPrefix = m_commonPrefix;
+ m_catalog.push_back(commonPrefix.append((*i)));
+ }
+}
+
+template<encoding::Tag TAG>
+size_t
+TorrentFile::encodeContent(EncodingImpl<TAG>& encoder) const
+{
+ // TorrentFileContent ::= CONTENT-TYPE TLV-LENGTH
+ // Suffix+
+ // CommonPrefix
+ // TorrentFilePtr?
+
+ // Suffix ::= NAME-TYPE TLV-LENGTH
+ // Name
+
+ // CommonPrefix ::= NAME-TYPE TLV-LENGTH
+ // Name
+
+ // TorrentFilePtr ::= NAME-TYPE TLV-LENGTH
+ // Name
+
+ size_t totalLength = 0;
+ for (const auto& name : m_suffixCatalog | boost::adaptors::reversed) {
+ size_t fileManifestSuffixLength = 0;
+ fileManifestSuffixLength += name.wireEncode(encoder);
+ totalLength += fileManifestSuffixLength;
+ }
+ totalLength += m_commonPrefix.wireEncode(encoder);
+ if (!m_torrentFilePtr.empty()) {
+ size_t torrentFilePtrLength = 0;
+ torrentFilePtrLength += m_torrentFilePtr.wireEncode(encoder);
+ totalLength += torrentFilePtrLength;
+ }
+
+ totalLength += encoder.prependVarNumber(totalLength);
+ totalLength += encoder.prependVarNumber(tlv::Content);
+ return totalLength;
+}
+
+bool
+TorrentFile::erase(const Name& name)
+{
+ auto found = std::find(m_catalog.begin(), m_catalog.end(), name);
+ if (found != m_catalog.end()) {
+ m_catalog.erase(found);
+ return true;
+ }
+ return false;
+}
+
+void
+TorrentFile::encodeContent()
+{
+ onChanged();
+
+ EncodingEstimator estimator;
+ size_t estimatedSize = encodeContent(estimator);
+
+ EncodingBuffer buffer(estimatedSize, 0);
+ encodeContent(buffer);
+
+ setContentType(tlv::ContentType_Blob);
+ setContent(buffer.block());
+}
+
+void
+TorrentFile::decodeContent()
+{
+ // TorrentFileContent ::= CONTENT-TYPE TLV-LENGTH
+ // Suffix+
+ // CommonPrefix
+ // TorrentFilePtr?
+
+ // Suffix ::= NAME-TYPE TLV-LENGTH
+ // Name
+
+ // CommonPrefix ::= NAME-TYPE TLV-LENGTH
+ // Name
+
+ // TorrentFilePtr ::= NAME-TYPE TLV-LENGTH
+ // Name
+
+ if (getContentType() != tlv::ContentType_Blob) {
+ BOOST_THROW_EXCEPTION(Error("Expected Content Type Blob"));
+ }
+
+ const Block& content = Data::getContent();
+ content.parse();
+
+ // Check whether there is a TorrentFilePtr
+ auto element = content.elements_begin();
+ if (content.elements_end() == element) {
+ BOOST_THROW_EXCEPTION(Error(".Torrent-file with empty content"));
+ }
+ element->parse();
+ Name name(*element);
+ if (name.empty())
+ BOOST_THROW_EXCEPTION(Error("Empty name included in the .torrent-file"));
+
+ if (name.get(name.size() - 3) == name::Component(".torrent-file")) {
+ m_torrentFilePtr = name;
+ ++element;
+ m_commonPrefix = Name(*element);
+ if (m_commonPrefix.empty()) {
+ BOOST_THROW_EXCEPTION(Error("Common prefix cannot be empty"));
+ }
+ }
+ else {
+ m_commonPrefix = name;
+ }
+ element++;
+ for (; element != content.elements_end(); ++element) {
+ element->parse();
+ Name fileManifestSuffix(*element);
+ if (fileManifestSuffix.empty())
+ BOOST_THROW_EXCEPTION(Error("Empty manifest file name included in the .torrent-file"));
+ this->insertToSuffixCatalog(fileManifestSuffix);
+ }
+ if (m_suffixCatalog.size() == 0) {
+ BOOST_THROW_EXCEPTION(Error(".Torrent-file with empty catalog of file manifest names"));
+ }
+}
+
+void
+TorrentFile::wireDecode(const Block& wire)
+{
+ m_catalog.clear();
+ m_suffixCatalog.clear();
+ Data::wireDecode(wire);
+ this->decodeContent();
+ this->constructLongNames();
+}
+
+const Block&
+TorrentFile::wireEncode()
+{
+ this->createSuffixCatalog();
+ this->encodeContent();
+ m_suffixCatalog.clear();
+ return Data::wireEncode();
+}
+
+} // namespace ntorrent
+
+} // namespace ndn
diff --git a/src/torrent-file.hpp b/src/torrent-file.hpp
new file mode 100644
index 0000000..89d3173
--- /dev/null
+++ b/src/torrent-file.hpp
@@ -0,0 +1,226 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+* Copyright (c) 2016 Regents of the University of California.
+*
+* This file is part of the nTorrent codebase.
+*
+* nTorrent 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.
+*
+* nTorrent 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 nTorrent, e.g., in COPYING.md file. If not, see
+* <http://www.gnu.org/licenses/>.
+*
+* See AUTHORS for complete list of nTorrent authors and contributors.
+*/
+
+#ifndef TORRENT_FILE_HPP
+#define TORRENT_FILE_HPP
+
+#include <ndn-cxx/name.hpp>
+#include <ndn-cxx/encoding/block.hpp>
+#include <ndn-cxx/data.hpp>
+
+#include <memory>
+
+namespace ndn {
+
+namespace ntorrent {
+
+class TorrentFile : public Data {
+public:
+ class Error : public Data::Error
+ {
+ public:
+ explicit
+ Error(const std::string& what)
+ : Data::Error(what)
+ {
+ }
+ };
+
+ /**
+ * @brief Create a new empty .TorrentFile.
+ */
+ TorrentFile() = default;
+
+ /**
+ * @brief Create a new .TorrentFile.
+ * @param torrentFileName The name of the .torrent-file
+ * @param torrentFilePtr A pointer (name) to the next segment of the .torrent-file
+ * @param commonPrefix The common name prefix of the manifest file names included in the catalog
+ * @param catalog The catalog containing the name of each file manifest
+ */
+ TorrentFile(const Name& torrentFileName,
+ const Name& torrentFilePtr,
+ const Name& commonPrefix,
+ const std::vector<ndn::Name>& catalog);
+
+ /**
+ * @brief Create a new .TorrentFile.
+ * @param torrentFileName The name of the .torrent-file
+ * @param commonPrefix The common name prefix of the manifest file names included in the catalog
+ * @param catalog The catalog containing the name of each file manifest
+ */
+ TorrentFile(const Name& torrentFileName,
+ const Name& commonPrefix,
+ const std::vector<ndn::Name>& catalog);
+
+ /**
+ * @brief Create a new .TorrentFile
+ * @param block The block format of the .torrent-file
+ */
+ explicit
+ TorrentFile(const Block& block);
+
+ /**
+ * @brief Get the name of the .TorrentFile
+ */
+ const Name&
+ getName() const;
+
+ /**
+ * @brief Get the common prefix of the file manifest names of this .torrent-file
+ */
+ const Name&
+ getCommonPrefix() const;
+
+ /**
+ * @brief Get a shared pointer to the name of the next segment of the .torrent-file.
+ *
+ * If there is no next segment, it returns a nullptr
+ */
+ shared_ptr<Name>
+ getTorrentFilePtr() const;
+
+ /**
+ * @brief Get the catalog of names of the file manifests
+ */
+ const std::vector<Name>&
+ getCatalog() const;
+
+ /**
+ * @brief Decode from wire format
+ */
+ void
+ wireDecode(const Block& wire);
+
+ /**
+ * @brief Encode from wire format
+ */
+ const Block&
+ wireEncode();
+
+ /**
+ * @brief Insert a name to the catalog of file manifest names
+ */
+ void
+ insert(const Name& name);
+
+ /**
+ * @brief Erase a name from the catalog of file manifest names
+ */
+ bool
+ erase(const Name& name);
+
+ /**
+ * @brief Get the size of the catalog of file manifest names
+ */
+ size_t
+ catalogSize() const;
+
+protected:
+ /**
+ * @brief prepend .torrent file as a Content block to the encoder
+ */
+ template<encoding::Tag TAG>
+ size_t
+ encodeContent(EncodingImpl<TAG>& encoder) const;
+
+ void
+ encodeContent();
+
+ void
+ decodeContent();
+
+private:
+ /**
+ * @brief Check whether the .torrent-file has a pointer to the next segment
+ */
+ bool
+ hasTorrentFilePtr() const;
+
+ /**
+ * @brief Create a catalog of suffixes for the names of the file manifests
+ *
+ * To optimize encoding and decoding, we encode the name of the file manifests
+ * as suffixes along with their common prefix.
+ *
+ */
+ void
+ createSuffixCatalog();
+
+ /**
+ * @brief Construct the catalog of long names from a catalog of suffixes for the file
+ * manifests' name
+ *
+ * After decoding a .torrent-file from its wire format, we construct the catalog of
+ * long names from the decoded common prefix and suffixes
+ *
+ */
+ void
+ constructLongNames();
+
+ /**
+ * @brief Insert a suffix to the suffix catalog
+ */
+ void
+ insertToSuffixCatalog(const PartialName& suffix);
+
+private:
+ Name m_commonPrefix;
+ Name m_torrentFilePtr;
+ std::vector<ndn::Name> m_suffixCatalog;
+ std::vector<ndn::Name> m_catalog;
+};
+
+inline bool
+TorrentFile::hasTorrentFilePtr() const
+{
+ return !m_torrentFilePtr.empty();
+}
+
+inline const std::vector<Name>&
+TorrentFile::getCatalog() const
+{
+ return m_catalog;
+}
+
+inline size_t
+TorrentFile::catalogSize() const
+{
+ return m_catalog.size();
+}
+
+inline void
+TorrentFile::insert(const Name& name)
+{
+ m_catalog.push_back(name);
+}
+
+inline void
+TorrentFile::insertToSuffixCatalog(const PartialName& suffix)
+{
+ m_suffixCatalog.push_back(suffix);
+}
+
+} // namespace ntorrent
+
+} // namespace ndn
+
+#endif // TORRENT_FILE_HPP