rawsockheader.hpp

/*------------------------------------------------------------------------------
    Copyright Butterfly Energy Systems 2014-2015.
    Distributed under the Boost Software License, Version 1.0.
    http://www.boost.org/LICENSE_1_0.txt
------------------------------------------------------------------------------*/
 
#ifndef CPPWAMP_INTERNAL_RAWSOCKHEADER_HPP
#define CPPWAMP_INTERNAL_RAWSOCKHEADER_HPP
 
#include <cstdint>
#include "endian.hpp"
 
namespace wamp
{
 
namespace internal
{
 
//------------------------------------------------------------------------------
enum class RawsockMsgType
{
    wamp,
    ping,
    pong
};
 
//------------------------------------------------------------------------------
class RawsockHeader
{
public:
    static RawsockHeader fromBigEndian(uint32_t big)
        {return RawsockHeader(endian::bigToNative32(big));}
 
    RawsockHeader() : hdr_(0) {}
 
    explicit RawsockHeader(uint32_t hostOrder) : hdr_(hostOrder) {}
 
    bool msgTypeIsValid() const
    {
        auto type = msgType();
        return type == RawsockMsgType::wamp ||
               type == RawsockMsgType::ping ||
               type == RawsockMsgType::pong;
    }
 
    RawsockMsgType msgType() const
    {
        return get<RawsockMsgType>(msgTypeMask_, msgTypePos_);
    }
 
    size_t length() const {return get<size_t>(lengthMask_);}
 
    uint32_t toBigEndian() const {return endian::nativeToBig32(hdr_);}
 
    uint32_t toHostOrder() const {return hdr_;}
 
    RawsockHeader& setMsgType(RawsockMsgType msgType)
        {return put(msgType, msgTypePos_);}
 
    RawsockHeader& setLength(size_t length)
        {return put(length, lengthPos_);}
 
private:
    static constexpr uint32_t msgTypeMask_  = 0xff000000;
    static constexpr uint32_t lengthMask_   = 0x00ffffff;
    static constexpr int msgTypePos_        = 24;
    static constexpr int lengthPos_         = 0;
 
    template <typename T = uint32_t>
    T get(uint32_t mask, int pos = 0) const
        {return static_cast<T>((hdr_ & mask) >> pos);}
 
    template <typename T>
    RawsockHeader& put(T value, int pos = 0)
        {hdr_ |= (static_cast<uint32_t>(value) << pos); return *this;}
 
    uint32_t hdr_;
};
 
} // namespace internal
 
} // namespace wamp
 
#endif // CPPWAMP_INTERNAL_RAWSOCKHEADER_HPP