doc/html/boost_asio/example/cpp03/chat/chat_message.hpp
//
// chat_message.hpp
// ~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2023 Christopher M. Kohlhoff (chris at kohlhoff dot com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#ifndef CHAT_MESSAGE_HPP
#define CHAT_MESSAGE_HPP
#include <cstdio>
#include <cstdlib>
#include <cstring>
class chat_message
{
public:
enum
{
header_length = 4,
max_body_length = 512
};
chat_message()
: body_length_(0)
{
}
const char* data() const
{
return data_;
}
char* data()
{
return data_;
}
size_t length() const
{
return header_length + body_length_;
}
const char* body() const
{
return data_ + header_length;
}
char* body()
{
return data_ + header_length;
}
size_t body_length() const
{
return body_length_;
}
void body_length(size_t new_length)
{
body_length_ = new_length;
if (body_length_ > max_body_length)
body_length_ = max_body_length;
}
bool decode_header()
{
using namespace std; // For strncat and atoi.
char header[header_length + 1] = "";
strncat(header, data_, header_length);
body_length_ = atoi(header);
if (body_length_ > max_body_length)
{
body_length_ = 0;
return false;
}
return true;
}
void encode_header()
{
using namespace std; // For sprintf and memcpy.
char header[header_length + 1] = "";
sprintf(header, "%4d", static_cast<int>(body_length_));
memcpy(data_, header, header_length);
}
private:
char data_[header_length + max_body_length];
size_t body_length_;
};
#endif // CHAT_MESSAGE_HPP