由于某种原因,这会导致访问冲突,但是没有任何详细的文档/帮助,我不知道我在哪里做错了.由于我在boost站点上看到的这应该是正确的,并将每个asio :: write调用的内容从客户端打印到新行.客户似乎工作正常.虽然服务器崩溃,但它还没有发送任何东西.
访问冲突发生在第275行的basic_stream_socket.hpp中.原因似乎是对象(boost :: asio :: stream_socket_service)没有初始化(this指针的值是0xfeeefeee),但我不明白为什么事实并非如此.
程序输出：
Start server
Server::startAccept()
Server::handleAccept()
Connection accepted
Connection::startRead()
Server::startAccept()
Connection::handleRead()
READ ERROR: The I/O operation has been aborted because either a thread exited or an application request
Connection::startRead()
#include "precompiled.h"
#include "db.h"
class Connection
: public boost::enable_shared_from_this<Connection>
{
public:
typedef boost::shared_ptr<Connection> Pointer;
static Pointer create(boost::asio::io_service& ioService)
{
return Pointer(new Connection(ioService));
}
ip::tcp::socket& getSocket()
{
return socket;
}
void startRead()
{
std::cout << "Connection::startRead()" << std::endl;
socket.async_read_some(boost::asio::buffer(readBuffer),boost::bind(&Connection::handleRead,this,_1,_2));
}
private:
Connection(asio::io_service& ioService)
: socket(ioService)
{
}
void handleWrite(const boost::system::error_code&,size_t)
{
}
void handleRead(const boost::system::error_code&error,size_t len)
{
std::cout << "Connection::handleRead()" << std::endl;
if(error)
{
std::cout << "READ ERROR: ";
std::cout << boost::system::system_error(error).what();
std::cout << std::endl;
}
else
{
std::cout << "read: ";
std::cout.write(readBuffer.data(),len);
std::cout << std::endl;
}
startRead();
}
boost::array<char,256> readBuffer;
ip::tcp::socket socket;
};
class Server
{
public:
Server(asio::io_service& ioService)
:acceptor(ioService,ip::tcp::endpoint(ip::tcp::v4(),getPort()))
{
startAccept();
}
private:
void startAccept()
{
std::cout << "RServer::startAccept()" << std::endl;
Connection::Pointer newConn =
Connection::create(acceptor.io_service());
acceptor.async_accept(newConn->getSocket(),boost::bind(&Server::handleAccept,newConn,asio::placeholders::error));
}
void handleAccept(Connection::Pointer newConn,const boost::system::error_code& error)
{
std::cout << "Server::handleAccept()" << std::endl;
if(error)
{
std::cout << "CONNECTION ERROR: ";
std::cout << boost::system::system_error(error).what();
std::cout << std::endl;
}
else
{
std::cout << "Connection accepted" << std::endl;
startAccept();
newConn->startRead();
}
}
ip::tcp::acceptor acceptor;
};
int main()
{
std::cout << "Start server" << std::endl;
asio::io_service ioService;
RemoteAdminServer server(ioService);
boost::system::error_code error;
ioService.run(error);
}
解决方法
您应该更改此代码段：
void startRead()
{
std::cout << "Connection::startRead()" << std::endl;
socket.async_read_some(boost::asio::buffer(readBuffer),_2));
}
至：
void startRead()
{
std::cout << "Connection::startRead()" << std::endl;
socket.async_read_some(boost::asio::buffer(readBuffer),this->shared_from_this(),_2));
}
请注意,我将共享指针传递给bind.这将保持Connection实例,直到调用处理程序.否则,在Server :: startAccept中使用计数变为零,并删除该对象.然后,当调用处理程序时,内存无效,您会遇到可怕的“未定义行为”.
