lp: Packet and Fields
refs #2879
Change-Id: Ie450eb58d1176179efed8d1706d30ea4978b7b02
diff --git a/src/lp/packet.hpp b/src/lp/packet.hpp
new file mode 100644
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--- /dev/null
+++ b/src/lp/packet.hpp
@@ -0,0 +1,224 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2013-2015 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.
+ */
+
+#ifndef NDN_CXX_LP_PACKET_HPP
+#define NDN_CXX_LP_PACKET_HPP
+
+#include "fields.hpp"
+
+namespace ndn {
+namespace lp {
+
+class Packet
+{
+public:
+ class Error : public ndn::tlv::Error
+ {
+ public:
+ explicit
+ Error(const std::string& what)
+ : ndn::tlv::Error(what)
+ {
+ }
+ };
+
+ Packet();
+
+ explicit
+ Packet(const Block& wire);
+
+ /**
+ * \brief append packet to encoder
+ */
+ template<encoding::Tag TAG>
+ size_t
+ wireEncode(EncodingImpl<TAG>& encoder) const;
+
+ /**
+ * \brief encode packet into wire format
+ */
+ const Block&
+ wireEncode() const;
+
+ /**
+ * \brief decode packet from wire format
+ */
+ void
+ wireDecode(const Block& wire);
+
+public: // field access
+ /**
+ * \return true if FIELD occurs one or more times
+ * \detail This is equivalent to count()>0
+ */
+ template<typename FIELD>
+ bool
+ has() const
+ {
+ return count<FIELD>() > 0;
+ }
+
+ /**
+ * \return number of occurrences of FIELD
+ */
+ template<typename FIELD>
+ size_t
+ count() const
+ {
+ m_wire.parse();
+
+ return std::count_if(m_wire.elements_begin(), m_wire.elements_end(),
+ [] (const Block& block) {
+ return block.type() == FIELD::TlvType::value; });
+ }
+
+ /**
+ * \return value of index-th occurrence of FIELD
+ * \throw std::out_of_range if index>=count()
+ */
+ template<typename FIELD>
+ typename FIELD::ValueType
+ get(size_t index = 0) const
+ {
+ m_wire.parse();
+
+ size_t count = 0;
+ for (const Block& element : m_wire.elements()) {
+ if (element.type() != FIELD::TlvType::value) {
+ continue;
+ }
+ if (count++ == index) {
+ return FIELD::decode(element);
+ }
+ }
+
+ throw std::out_of_range("Index out of range");
+ }
+
+ /**
+ * \return values of all occurrences of FIELD
+ */
+ template<typename FIELD>
+ std::vector<typename FIELD::ValueType>
+ list() const
+ {
+ std::vector<typename FIELD::ValueType> output;
+
+ m_wire.parse();
+
+ for (const Block& element : m_wire.elements()) {
+ if (element.type() != FIELD::TlvType::value) {
+ continue;
+ }
+ output.push_back(FIELD::decode(element));
+ }
+
+ return output;
+ }
+
+ /**
+ * \brief remove all occurrences of FIELD, and add a FIELD with value
+ * \detail This equivalent to clear() followed by add(value)
+ */
+ template<typename FIELD>
+ Packet&
+ set(const typename FIELD::ValueType& value)
+ {
+ clear<FIELD>();
+ return add<FIELD>(value);
+ }
+
+ /**
+ * \brief add a FIELD with value
+ * \throw std::length_error if field already exists and is not repeatable
+ */
+ template<typename FIELD>
+ Packet&
+ add(const typename FIELD::ValueType& value)
+ {
+ if (!FIELD::IsRepeatable::value && has<FIELD>()) {
+ throw std::length_error("Field cannot be repeated");
+ }
+
+ EncodingEstimator estimator;
+ size_t estimatedSize = FIELD::encode(estimator, value);
+ EncodingBuffer buffer(estimatedSize, 0);
+ FIELD::encode(buffer, value);
+ Block block = buffer.block();
+
+ Block::element_const_iterator pos = std::lower_bound(m_wire.elements_begin(),
+ m_wire.elements_end(),
+ FIELD::TlvType::value,
+ comparePos);
+ m_wire.insert(pos, block);
+
+ return *this;
+ }
+
+ /**
+ * \brief remove the index-th occurrence of FIELD
+ * \throw std::out_of_range if index>=count()
+ */
+ template<typename FIELD>
+ Packet&
+ remove(size_t index = 0)
+ {
+ m_wire.parse();
+
+ size_t count = 0;
+ for (Block::element_const_iterator it = m_wire.elements_begin(); it != m_wire.elements_end();
+ ++it) {
+ if (it->type() == FIELD::TlvType::value) {
+ if (count == index) {
+ m_wire.erase(it);
+ return *this;
+ }
+ count++;
+ }
+ }
+
+ throw std::out_of_range("Index out of range");
+ }
+
+ /**
+ * \brief remove all occurrences of FIELD
+ */
+ template<typename FIELD>
+ Packet&
+ clear()
+ {
+ m_wire.parse();
+ m_wire.remove(FIELD::TlvType::value);
+ return *this;
+ }
+
+private:
+ static bool
+ comparePos(const Block& first, const uint64_t second);
+
+private:
+ mutable Block m_wire;
+};
+
+} // namespace lp
+} // namespace ndn
+
+#endif // NDN_CXX_LP_PACKET_HPP
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