boost库asio详解8——几个TCP的简单例子

摘于boost官网的几个例子, 做了点小修改, 笔记之.

同步客户端

void test_asio_synclient()
{
    typedef boost::asio::io_service IoService;
    // 该命名空间下有几个常用类: accetpt, resolver, endpoint, socket
    typedef boost::asio::ip::tcp TCP;

    try
    {
        IoService ios;
        boost::system::error_code error;

        // 1. 用解释器的方法, 常用来解析域名, 如
        // query("www.163.com","80"), 也可以 query("www.163.com","telnet")
        // echo          7/tcp
        // ftp           21/tcp                 # File Transfer Protocol (Control)
        // telnet        23/tcp                 # Virtual Terminal Protocol
        // smtp          25/tcp                 # Simple Mail Transfer Protocol
        // time          37/tcp  timeserver     # Time
//      TCP::resolver resolver(ios);
//      TCP::resolver::query query("127.0.0.1", "10000");
//      TCP::resolver::iterator endpoint_iterator = resolver.resolve(query);
//      TCP::resolver::iterator end;
//      TCP::socket socket(ios);
//      socket.connect(*endpoint_iterator, error);

        // 2. 用简便的方法
        TCP::socket socket(ios);
        TCP::endpoint endpoint(boost::asio::ip::address_v4::from_string("127.0.0.1"), 10000);
        socket.connect(endpoint, error);

        // 这里要判断一下, 否则没有连上会通过.
        if (error)
            throw boost::system::system_error(error);

        while(true)
        {
            // boost::array<char, 128> buf;
            std::vector<char> buf(128);
            size_t len = socket.read_some(boost::asio::buffer(buf), error);

            // 这是也要判断一下, 否则服务端运行断开, 这里会出现死循环.
            if (error == boost::asio::error::eof)
                break; // Connection closed cleanly by peer.
            else if (error)
                throw boost::system::system_error(error); // Some other error.

            // buf要注意控制大小。
            socket.write_some(boost::asio::buffer(buf, len), error);
        }
    }
    catch (std::exception& e)
    {
        PRINT_DEBUG(e.what());
    }
}

同步服务端

namespace
{
    std::string make_daytime_string()
    {
        using namespace std; // For time_t, time and ctime;
        time_t now = time(0);
        return ctime(&now);
    }
}

void test_asio_synserver()
{
    typedef boost::asio::io_service IoService;
    typedef boost::asio::ip::tcp TCP;

    try
    {
        IoService ios;
        /*
            *以下构造函数相当于以下步骤
            * basic_socket_acceptor<tcp> acceptor(io_service);
            * acceptor.open(tcp::v4());
            * acceptor.bind(tcp::endpoint(13));
            * acceptor.listen(0);//default
        */
        /*
            tcp::endpoint(端点)由以下三个部分组成
            1. IP地址(address, address_v4, address_v6)
            2. 端口号
            3. 协议版本
        */
        TCP::acceptor acceptor(ios, TCP::endpoint(TCP::v4(), 13));
        for (;;)
        {
            TCP::socket socket(ios);
            acceptor.accept(socket);
            std::string message = make_daytime_string();

            boost::system::error_code ignored_error;
            boost::asio::write(socket,
                               boost::asio::buffer(message),
                               boost::asio::transfer_all(),
                               ignored_error);
            PRINT_DEBUG(message);
        }
    }
    catch (std::exception& e)
    {
        std::cout << e.what() << std::endl;
    }
}

异步服务端

namespace
{
    typedef boost::asio::io_service IoService;
    typedef boost::asio::ip::tcp TCP;

    std::string make_daytime_string()
    {
        using namespace std;
        time_t now = std::time(NULL);
        return ctime(&now);
    }

    class tcp_connection
        : public boost::enable_shared_from_this<tcp_connection>
    {
    public:
        typedef boost::shared_ptr<tcp_connection> pointer;

        static pointer create(IoService& io_service)
        {
            return pointer(new tcp_connection(io_service));
        }

        TCP::socket& socket()
        {
            return socket_;
        }

        void start()
        {
            message_ = make_daytime_string();

            boost::asio::async_write(
                socket_,
                boost::asio::buffer(message_),
                boost::bind(&tcp_connection::handle_write,
                            shared_from_this(),
                            boost::asio::placeholders::error,
                            boost::asio::placeholders::bytes_transferred));
        }
    private:
        tcp_connection(IoService& io_service)
            : socket_(io_service)
        {
        }

        void handle_write(const boost::system::error_code& /*error*/,
            size_t /*bytes_transferred*/)
        {
            PRINT_DEBUG("write data!!!");
        }

        TCP::socket socket_;
        std::string message_;
    };

    class tcp_server
    {
    public:
        tcp_server(IoService& io_service)
            : acceptor_(io_service, TCP::endpoint(TCP::v4(), 10000))
        {
            start_accept();
        }
    private:
        void start_accept()
        {
            tcp_connection::pointer new_connection =
                tcp_connection::create(acceptor_.get_io_service());

            acceptor_.async_accept(
                new_connection->socket(),
                boost::bind(&tcp_server::handle_accept,
                            this,
                            new_connection,
                            boost::asio::placeholders::error));
        }

        void handle_accept(tcp_connection::pointer new_connection,
            const boost::system::error_code& error)
        {
            if (!error)
            {
                new_connection->start();
                start_accept();
            }
        }

        TCP::acceptor acceptor_;
    };
}

// tcp_connection与tcp_server封装后
void test_asio_asynserver()
{
    try
    {
        IoService io_service;
        tcp_server server(io_service);

        // 只有io_service类的run()方法运行之后回调对象才会被调用
        io_service.run();
    }
    catch (std::exception& e)
    {
        std::cerr << e.what() << std::endl;
    }
}

 

http://blog.csdn.net/huang_xw/article/details/8518740