2012-08-16 87 views
0

如果使用Boost.Asio的使用echo服务器的实例中编程TCP服务器,我已经修改了它的一些代码,以满足我的要求,我想处理输入数据和发回的结果,我用套接字处理类“socket.h”,我想为另一个处理程序中的文件“handler.h”中的数据,我现在的问题是如何将数据传递给函数handler.h并通过socket.h传递此函数的数据。的boost :: ASIO ::从外部类ASYNC_WRITE

socket.h中

#include <cstdlib> 
#include <iostream> 
#include <boost/bind.hpp> 
#include <boost/asio.hpp> 
#include <json/json.h> 
#include "handler.h" 

using namespace std; 
using boost::asio::ip::tcp; 

class session { 
public: 
    session(boost::asio::io_service& io_service) : socket_(io_service) {} 
    tcp::socket& socket() { return socket_; } 

    /* listen for first input data after connection established */ 
    void start() { 
     socket_.async_read_some(boost::asio::buffer(data_, max_length), 
     boost::bind(&session::handleIncome,this, 
     boost::asio::placeholders::error, 
     boost::asio::placeholders::bytes_transferred)); } 

    /* handle incoming data */ 
    void handleIncome(const boost::system::error_code& error, size_t bytes_transferred) { 
     /* data is recieved in var data_ */ 
      if (!error) { 
      /********************* Data Handler ****************************/ 

        callHandler(data_); //this is in handler.cpp 

      /**************************************************************/ 
     } else { delete this; } } 

    /* get more input */ 
    void getIncome(const boost::system::error_code& error) { 
     if (!error) { 
      socket_.async_read_some(boost::asio::buffer(data_, max_length), 
      boost::bind(&session::handleIncome, this, 
      boost::asio::placeholders::error, 
      boost::asio::placeholders::bytes_transferred)); } 
    else { delete this; } } 

    /* send outcome back to client */ 
    void sendOutcome(const std::string dout, size_t bytes_out) { 
     boost::asio::async_write(socket_,boost::asio::buffer(dout, bytes_out), 
     boost::bind(&session::getIncome, this,boost::asio::placeholders::error)); } 

private: 
    tcp::socket socket_; 
    enum { max_length = 1024 }; 
    char data_[max_length]; 
}; 

class DServer { 
public: 
    DServer(boost::asio::io_service& io_service, short port) 
    :io_service_(io_service), 
    acceptor_(io_service, tcp::endpoint(tcp::v4(), port)) 

    { 
     session* new_session = new session(io_service_); 
     acceptor_.async_accept(new_session->socket(), 
     boost::bind(&DServer::handle_accept,this,new_session,boost::asio::placeholders::error)); 
    } 

    void handle_accept(session* new_session,const boost::system::error_code& error) { 
    if (!error) { 
     new_session->start(); 
     new_session = new session(io_service_); 
     acceptor_.async_accept(new_session->socket(),boost::bind(&DServer::handle_accept, this, new_session,boost::asio::placeholders::error));} 
    else { delete new_session; } } 

private: 
    boost::asio::io_service& io_service_; 
    tcp::acceptor acceptor_; 
}; 

handler.cpp

void callHandler(string data) { 
    /* here i want to process data and after that i want to send back the result to the same client ofcourse using the function sendOutcome() in the socket.h file */ 
} 

回答

2

最常见的方式是通过返回从函数返回值:

string callHandler(string data); 

sendOutcome(callHandler(data_)); 

如果您需要更多灵活性(例如,发送多个响应或者使用套接字执行其他操作),然后传递对套接字的引用,或者传递对象的引用(可能使用抽象接口将其与类实现分离)。

0

首先,您必须确保您已收到您需要的所有数据。您的处理程序应该处理handleIncome()回调调用的场景,即使整个请求比较大,bytes_transferred也是1。

而原因,你应该而不是使用读取回调作为async_write()函数的参数。