tld_packet.hpp

Go to the documentation of this file.

// tld_packet.hpp
/*
 *  Copyright (c) 2007 Leigh Johnston.
 *
 *  All rights reserved.
 *
 *  Redistribution and use in source and data forms, with or without
 *  modification, are permitted provided that the following conditions are
 *  met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *
 *     * Redistributions in data form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *
 *     * Neither the name of Leigh Johnston nor the names of any
 *       other contributors to this software may be used to endorse or
 *       promote products derived from this software without specific prior
 *       written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 *  IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 *  THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 *  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 *  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 *  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 *  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 *  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
 
#pragma once
 
#include <neolib/neolib.hpp>
#include <vector>
#include <neolib/io/binary_data_packet.hpp>
 
namespace neolib
{
    template <typename IdType, std::size_t MaxPacketSize = 1024, typename CharType = char, typename PacketTraits = DefaultPacketTraits>
    class basic_tld_packet : basic_binary_data_packet<CharType, PacketTraits>
    {
        typedef tld_packet<IdType, CharType, PacketTraits> self_type;
        typedef basic_binary_data_packet<CharType> base_type;
        // types
    public:
        typedef base_type::character_type character_type;
        typedef base_type::const_pointer const_pointer;
        typedef base_type::pointer pointer;
        typedef base_type::size_type size_type;
        typedef base_type::const_iterator const_iterator;
        typedef base_type::iterator iterator;
        typedef base_type::string_type string_type;
    private:
        typedef std::vector<CharType> contents_type;
        typedef typename contents_type::size_type contents_offset_type;
        // construction
        basic_tld_packet()
        {
            allocate(0);
        }
        // interface
    public:
        virtual const_pointer data() const
        {
            return &iContents[0];
        }
        virtual pointer data()
        {
            return &iContents[0];
        }
        virtual size_type length() const
        {
            return iContents.size();
        }
        virtual bool has_max_length() const
        {
            return MaxPacketSize != 0;
        }
        virtual size_type max_length() const
        {
            return MaxPacketSize;
        }
        virtual void clear()
        {
            iContents.clear();
            allocate(0);
            iWritePosition = iContents.size();
            iReadPosition = PacketTraits::HeaderSize;
        }
        virtual bool take_some(const_pointer& aFirst, const_pointer aLast)
        {
        }
        virtual clone_pointer clone() const
        {
            return clone_pointer(new self_type(*this));
        }
        virtual void copy_from(const basic_packet<CharType>& aSource)
        {
            iContents = aSource.iContents;
            allocate(0);
            iWritePosition = iContents.size();
            iReadPosition = PacketTraits::HeaderSize;
        }
        void encode(IdType Id)
        {
            contents_offset_type oldPosition = iWritePosition;
            iWritePosition = PacketTraits::IdOffset;
            encode(static_cast<uint32_t>(Id));
            iWritePosition = oldPosition;
        }
        IdType id() const
        {
            contents_offset_type oldPosition = iReadPosition;
            iReadPosition = PacketTraits::IdOffset;
            IdType result = static_cast<IdType>(decode<uint32_t>());
            iReadPosition = oldPosition;
            return result;
        }
        // implementation
    private:
        virtual void write(const void* aData, std::size_t aLength)
        {
        }
        virtual void read(void* aData, std::size_t aLength) const
        {
        }
        void allocate(std::size_t aLength)
        {
            iContents.resize(std::max(iContents.size() + aLength, PacketTraits::HeaderSize));
        }
        // attributes
    private:
        contents_type iContents;
        contents_offset_type iWritePosition;
        mutable contents_offset_type iReadPosition;
    };
 
    typedef basic_data_packet<char> data_packet;
}