peerplays_migrated/libraries/net/include/graphene/net/message.hpp
2015-06-08 12:36:37 -04:00

111 lines
3.9 KiB
C++

/*
* Copyright (c) 2015, Cryptonomex, Inc.
* All rights reserved.
*
* This source code is provided for evaluation in private test networks only, until September 8, 2015. After this date, this license expires and
* the code may not be used, modified or distributed for any purpose. Redistribution and use in source and binary forms, with or without modification,
* are permitted until September 8, 2015, provided that the following conditions are met:
*
* 1. The code and/or derivative works are used only for private test networks consisting of no more than 10 P2P nodes.
*
* 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 HOLDER 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 <fc/array.hpp>
#include <fc/io/varint.hpp>
#include <fc/network/ip.hpp>
#include <fc/io/raw.hpp>
#include <fc/crypto/ripemd160.hpp>
#include <fc/reflect/variant.hpp>
namespace graphene { namespace net {
/**
* Defines an 8 byte header that is always present because the minimum encrypted packet
* size is 8 bytes (blowfish). The maximum message size is defined in config.hpp. The channel,
* and message type is also included because almost every channel will have a message type
* field and we might as well include it in the 8 byte header to save space.
*/
struct message_header
{
uint32_t size; // number of bytes in message, capped at MAX_MESSAGE_SIZE
uint32_t msg_type; // every channel gets a 16 bit message type specifier
};
typedef fc::uint160_t message_hash_type;
/**
* Abstracts the process of packing/unpacking a message for a
* particular channel.
*/
struct message : public message_header
{
std::vector<char> data;
message(){}
message( message&& m )
:message_header(m),data( std::move(m.data) ){}
message( const message& m )
:message_header(m),data( m.data ){}
/**
* Assumes that T::type specifies the message type
*/
template<typename T>
message( const T& m )
{
msg_type = T::type;
data = fc::raw::pack(m);
size = (uint32_t)data.size();
}
fc::uint160_t id()const
{
return fc::ripemd160::hash( data.data(), (uint32_t)data.size() );
}
/**
* Automatically checks the type and deserializes T in the
* opposite process from the constructor.
*/
template<typename T>
T as()const
{
try {
FC_ASSERT( msg_type == T::type );
T tmp;
if( data.size() )
{
fc::datastream<const char*> ds( data.data(), data.size() );
fc::raw::unpack( ds, tmp );
}
else
{
// just to make sure that tmp shouldn't have any data
fc::datastream<const char*> ds( nullptr, 0 );
fc::raw::unpack( ds, tmp );
}
return tmp;
} FC_RETHROW_EXCEPTIONS( warn,
"error unpacking network message as a '${type}' ${x} !=? ${msg_type}",
("type", fc::get_typename<T>::name() )
("x", T::type)
("msg_type", msg_type)
);
}
};
} } // graphene::net
FC_REFLECT( graphene::net::message_header, (size)(msg_type) )
FC_REFLECT_DERIVED( graphene::net::message, (graphene::net::message_header), (data) )