ET9_WebGL_Base/src/experimental/chat/chat_message.cc

//
// chat_client.cc
// ~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2010 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)
//

#include <cstdlib>
#include <deque>
#include <iostream>
#include <boost/bind.hpp>
#include <boost/asio.hpp>
#include <boost/thread.hpp>
#include "experimental/chat/chat_message.h"

using boost::asio::ip::tcp;

typedef std::deque<chat_message> chat_message_queue;

class chat_client
{
public:
	chat_client(boost::asio::io_service& io_service, tcp::resolver::iterator endpoint_iterator) :
		io_service_(io_service), socket_(io_service)
	{
		tcp::endpoint endpoint = *endpoint_iterator;
		socket_.async_connect(endpoint, boost::bind(&chat_client::handle_connect, this,
		        boost::asio::placeholders::error, ++endpoint_iterator));
	}

	void write(const chat_message& msg)
	{
		io_service_.post(boost::bind(&chat_client::do_write, this, msg));
	}

	void close()
	{
		io_service_.post(boost::bind(&chat_client::do_close, this));
	}

private:

	void handle_connect(const boost::system::error_code& error,
	        tcp::resolver::iterator endpoint_iterator)
	{
		if(!error)
		{
			boost::asio::async_read(socket_, boost::asio::buffer(read_msg_.data(),
			        chat_message::header_length), boost::bind(&chat_client::handle_read_header,
			        this, boost::asio::placeholders::error));
		}
		else if(endpoint_iterator != tcp::resolver::iterator())
		{
			socket_.close();
			tcp::endpoint endpoint = *endpoint_iterator;
			socket_.async_connect(endpoint, boost::bind(&chat_client::handle_connect, this,
			        boost::asio::placeholders::error, ++endpoint_iterator));
		}
	}

	void handle_read_header(const boost::system::error_code& error)
	{
		if(!error && read_msg_.decode_header())
		{
			boost::asio::async_read(socket_, boost::asio::buffer(read_msg_.body(),
			        read_msg_.body_length()), boost::bind(&chat_client::handle_read_body, this,
			        boost::asio::placeholders::error));
		}
		else
		{
			do_close();
		}
	}

	void handle_read_body(const boost::system::error_code& error)
	{
		if(!error)
		{
			std::cout.write(read_msg_.body(), read_msg_.body_length());
			std::cout << "\n";
			boost::asio::async_read(socket_, boost::asio::buffer(read_msg_.data(),
			        chat_message::header_length), boost::bind(&chat_client::handle_read_header,
			        this, boost::asio::placeholders::error));
		}
		else
		{
			do_close();
		}
	}

	void do_write(chat_message msg)
	{
		bool write_in_progress = !write_msgs_.empty();
		write_msgs_.push_back(msg);
		if(!write_in_progress)
		{
			boost::asio::async_write(socket_, boost::asio::buffer(write_msgs_.front().data(),
			        write_msgs_.front().length()), boost::bind(&chat_client::handle_write, this,
			        boost::asio::placeholders::error));
		}
	}

	void handle_write(const boost::system::error_code& error)
	{
		if(!error)
		{
			write_msgs_.pop_front();
			if(!write_msgs_.empty())
			{
				boost::asio::async_write(socket_, boost::asio::buffer(write_msgs_.front().data(),
				        write_msgs_.front().length()), boost::bind(&chat_client::handle_write,
				        this, boost::asio::placeholders::error));
			}
		}
		else
		{
			do_close();
		}
	}

	void do_close()
	{
		socket_.close();
	}

private:
	boost::asio::io_service& io_service_;
	tcp::socket socket_;
	chat_message read_msg_;
	chat_message_queue write_msgs_;
};

int main(int argc, char* argv[])
{
	try
	{
		if(argc != 3)
		{
			std::cerr << "Usage: chat_client <host> <port>\n";
			return 1;
		}

		boost::asio::io_service io_service;

		tcp::resolver resolver(io_service);
		tcp::resolver::query query(argv[1], argv[2]);
		tcp::resolver::iterator iterator = resolver.resolve(query);

		chat_client c(io_service, iterator);

		boost::thread t(boost::bind(&boost::asio::io_service::run, &io_service));

		char line[chat_message::max_body_length + 1];
		while(std::cin.getline(line, chat_message::max_body_length + 1))
		{
			using namespace std;
			// For strlen and memcpy.
			chat_message msg;
			msg.body_length(strlen(line));
			memcpy(msg.body(), line, msg.body_length());
			msg.encode_header();
			c.write(msg);
		}

		c.close();
		t.join();
	}
	catch(std::exception& e)
	{
		std::cerr << "Exception: " << e.what() << "\n";
	}

	return 0;
}