boost::asio::async_read doesn't call the handler and keeps receiving - c++

boost::asio::async_read doesn't call the handler and keeps receiving, am trying to receive some buffers that I don't know it's length , but max is 1024
#include "AsyncConnection.h"
AsyncConnection::AsyncConnection(boost::asio::io_service& io_service)
: socket(io_service)
{
}
AsyncConnection::~AsyncConnection()
{
}
AsyncConnection::Pointer AsyncConnection::Create(boost::asio::io_service& io_service){
return Pointer(new AsyncConnection(io_service));
}
boost::asio::ip::tcp::socket& AsyncConnection::GetSocket(){
return socket;
}
void AsyncConnection::BeginReceive(){
boost::asio::async_read(socket, boost::asio::buffer(buffer, 1024),
boost::bind(&AsyncConnection::EndReceive, shared_from_this(),
boost::asio::placeholders::error,
boost::asio::placeholders::bytes_transferred));
}
void AsyncConnection::EndReceive(const boost::system::error_code& error, std::size_t bytes_transferred){
if (!error){
}
else{
std::cout << error.message() << std::endl;
}
}
it never calls the EndReceive , my guess is it's keeping receiving until the buffer is full?! how to fix that tho!

Related

async_read handler not called

I try to make TCP asynchronous server, but I'm encountering some difficulties with async_read function. The handler async_read function is never called. I use this command to write on server's socket "nc -C 127.0.0.1 4242". Can you explain to me what I didn't understand or what mistakes I have made? Thanks for your help.
ChatSession.cpp
ChatSession::ChatSession(boost::asio::io_context& ioc)
: __socket(ioc)
{
}
ChatSession::pointer ChatSession::create(boost::asio::io_context& ioc)
{
return pointer(new ChatSession(ioc));
}
tcp::socket& ChatSession::socket()
{
return this->__socket;
}
void ChatSession::handle_start()
{
}
void ChatSession::start()
{
std::string buffer = "Bienvenue\n";
boost::asio::async_write(__socket, boost::asio::buffer(buffer),
boost::bind(&ChatSession::handle_start, shared_from_this()));
readHeader();
}
void ChatSession::handleReadHeader(const boost::system::error_code& error,
std::size_t byte_transferred)
{
if (!error && this->__readMessage.decodeHeader()) {
std::strcpy(__readMessage.getData(), __test.data());
std::cout << __readMessage.getData() << std::endl;
readBody();
} else {
std::cerr << "Erreur" << std::endl;
}
}
void ChatSession::readHeader()
{
__test.resize(6);
boost::asio::async_read(__socket,
boost::asio::buffer(__test),
boost::bind(
&ChatSession::handleReadHeader,
shared_from_this(),
boost::asio::placeholders::error,
}
TcpServer.cpp:
TcpServer::TcpServer(boost::asio::io_context& io_context, int port)
: __acceptor (io_context, tcp::endpoint(tcp::endpoint(tcp::v4(), port)))
{
startAccept();
}
void TcpServer::startAccept()
{
ChatSession::pointer newConnection = ChatSession::create(__io_context);
__acceptor.async_accept(newConnection->socket(),
boost::bind(&TcpServer::handle_accept, this, newConnection,
boost::asio::placeholders::error));
}
void TcpServer::handle_accept(ChatSession::pointer newConnection,
const boost::system::error_code& error)
{
if (!error) {
newConnection->start();
startAccept();
}
}
main.cpp:
int main(int ac, char** av) {
try {
boost::asio::io_context io_context;
TcpServer server(io_context, 4242);
io_context.run();
} catch(const std::exception& e) {
std::cerr << e.what() << std::endl;
}
return 0;
}

Memory leak when I using io_service::run

I am trying to write my socket class (code below).
At last everything works:reconnection, connection, message send, message receive
But I noticed memory leak when I repeat TCPSocketBody::Connect(const std::string &adress, const std::string &port) if for example host is unreachable. Size of my application is growing.
I discovered that when I remove line:
thread_io_service = boost::thread(boost::bind(&boost::asio::io_service::run, &io_service_global));
the problem disappears. But I need this line. What I am doing wrong?
I checked from command line number of thread in my application and it always is 1 or 2.
#include "TCPSocketBody.h"
TCPSocketBody::TCPSocketBody() : socket_(io_service_global),
resolver(io_service_global),
connected(false),
expectedMessage(0)
{
}
void TCPSocketBody::Close()
{
io_service_global.post(boost::bind(&TCPSocketBody::DoClose, this));
}
void TCPSocketBody::Connect(const std::string &adress, const std::string &port)
{
io_service_global.reset();
iterator = resolver.resolve({adress, port});
boost::asio::async_connect(socket_, iterator,
boost::bind(&TCPSocketBody::HandleConnect, this,
boost::asio::placeholders::error));
socket_.set_option(boost::asio::ip::tcp::no_delay(true));
thread_io_service = boost::thread(boost::bind(&boost::asio::io_service::run, &io_service_global));
}
void TCPSocketBody::HandleConnect(const boost::system::error_code& error)
{
if (!error)
{
connected = true;
boost::asio::async_read(socket_,
boost::asio::buffer(data_to_read, MessageCoder::BufferSize()), boost::asio::transfer_all(),
boost::bind(&TCPSocketBody::HandleReadHeader, this,
boost::asio::placeholders::error));
} else
{
Close();
}
}
void TCPSocketBody::HandleReadHeader(const boost::system::error_code& error)
{
expectedMessage = MessageCoder::HeaderToVal(data_to_read);
if (expectedMessage > MessageCoder::MaxMessageSize())
{
expectedMessage = 0;
Close();
} else
{
boost::asio::async_read(socket_,
boost::asio::buffer(data_to_read, expectedMessage), boost::asio::transfer_all(),
boost::bind(&TCPSocketBody::HandleReadMessage, this,
boost::asio::placeholders::error));
}
}
void TCPSocketBody::HandleReadMessage(const boost::system::error_code& error)
{
expectedMessage = 0;
boost::asio::async_read(socket_,
boost::asio::buffer(data_to_read, MessageCoder::BufferSize()), boost::asio::transfer_all(),
boost::bind(&TCPSocketBody::HandleReadHeader, this,
boost::asio::placeholders::error));
}
void TCPSocketBody::WriteMessage(char *dataToSend)
{
io_service_global.post(boost::bind(&TCPSocketBody::Write, this, dataToSend));
}
void TCPSocketBody::Write(char *dataToSend)
{
data = dataToSend;
boost::asio::async_write(socket_,
boost::asio::buffer(data, std::strlen(data)),
boost::bind(&TCPSocketBody::HandleWrite, this,
boost::asio::placeholders::error));
}
void TCPSocketBody::HandleWrite(const boost::system::error_code& error)
{
if (!error)
{
}
else
{
Close();
}
}
void TCPSocketBody::DoClose()
{
socket_.close();
connected = false;
}
Without the header file, it is hard to be certain. I suspect that thread_io_service is a member variable. A second call to 'Connect' will overwrite the existing value without destroying the object. Any memory allocated within the object will be leaked.
Perhaps try making a std::vector of thread_io_service and push_back each new thread on the connect call. The vector will destroy the contained objects when it gets destructed.
Valgrind can likely pinpoint the issue with more detail.

boost async_read_until calls handle read continuously

I've not found a specific reference to a solution to this problem. I am writing a server using a modified version of the boost asynch example 3. I am using async_read_until. when recieving the message the program calls the handle read and calls for a new thread but the streambuf is still contains the delimeter (i'm sending an xml from a different project) and immediately calls another thread up to my threadmax.
class server{
....
void server::run()
{
std::vector<boost::shared_ptr<boost::thread>> threads;
for (std::size_t i = 0; i < thread_pool_size_; ++i)
{
boost::shared_ptr<boost::thread> thread(new boost::thread(
boost::bind(&boost::asio::io_service::run, &io_service_)));
threads.push_back(thread);
}
//wait for all threads in the pool to exit.
for (std::size_t i = 0; i < threads.size(); ++i)
threads[i]->join();
}
void server::start_accept()
{
new_connection_.reset(new connection(io_service_, request_handler_));
acceptor_.async_accept(new_connection_->socket(),
boost::bind(&server::handle_accept, this,
boost::asio::placeholders::error));
}
void server::handle_accept(const boost::system::error_code& e)
{
if (!e)
{
new_connection_->start();
}
start_accept()
}
}
class connection{
....
void connection::start()
{
boost::asio::async_read_until(socket_, buffer_,
"<\\User>",
boost::bind(&connection::handle_read, shared_from_this(),
boost::asio::placeholders::error,
boost::asio::placeholders::bytes_transferred));
}
void connection::handle_read(const boost::system::error_code& e,
std::size_t bytes_transferred)
{
if(!e)
{
std::ostringstream ss;
std::cout << ss.str();
buffer_.consume(buffer_.size());
}
}

Boost Asio - Server doesn't receive message

I'm developing a 3d (first/third person) game and I'm trying to make it multiplayer using TCP sockets. I'm using the boost asio library for this, and I'm in a little over my head. I've played with the tutorials and examples a bit on the boost asio doc page and they compiled/ran/worked just fine, I'm just a little confused as to how everything works.
Right now I'm just trying to make the server accept messages from the client, and print the message after receiving it. When I execute the code below (it compiles/links/runs fine), nothing happens. More specifically, the client appears to successfully send the message, and the server never seems to receive the message.
Client code:
ClientFramework::ClientFramework() :
mResolver(mIOService)
{
}
bool ClientFramework::Initialize()
{
try
{
tcp::resolver::query query("localhost", "daytime");
tcp::resolver::iterator it = mResolver.resolve(query);
tcp::socket socket(mIOService);
boost::asio::connect(socket, it);
std::string s = "hello world";
boost::system::error_code e;
socket.write_some(boost::asio::buffer(s.c_str(), s.size()), e);
if (e)
{
throw boost::system::system_error(e);
}
} catch (std::exception& e)
{
gLog << LOG_ERROR << e.what() << "\n";
}
return true;
}
Server code:
ServerFramework::ServerFramework() :
mAcceptor(mIOService, tcp::endpoint(tcp::v4(), 13))
{
}
bool ServerFramework::Initialize()
{
mIOService.run();
StartAccept();
return true;
}
void ServerFramework::StartAccept()
{
Connection::ptr conn =
Connection::create(mAcceptor.get_io_service());
mAcceptor.async_accept(conn->Socket(),
boost::bind(&ServerFramework::HandleAccept, this, conn,
boost::asio::placeholders::error));
}
void ServerFramework::HandleAccept(Connection::ptr conn,
const boost::system::error_code& error)
{
if (!error)
{
conn->Initialize();
}
StartAccept();
}
Connection::ptr Connection::create(boost::asio::io_service& io_service)
{
return ptr(new Connection(io_service));
}
tcp::socket& Connection::Socket()
{
return mSocket;
}
void Connection::Initialize()
{
boost::asio::async_read(mSocket, boost::asio::buffer(buf, BUFFER_SIZE),
boost::bind(&Connection::handle_read, shared_from_this(),
boost::asio::placeholders::error,
boost::asio::placeholders::bytes_transferred));
}
Connection::Connection(boost::asio::io_service& io_service) :
mSocket(io_service)
{
}
void Connection::handle_read(const boost::system::error_code& e, size_t size)
{
std::string s(buf, size);
gLog << LOG_INFO << s << "\n";
boost::asio::async_read(mSocket, boost::asio::buffer(buf, BUFFER_SIZE),
boost::bind(&Connection::handle_read, shared_from_this(),
boost::asio::placeholders::error,
boost::asio::placeholders::bytes_transferred));
}
It does not look like your io_service has any work to do when you invoke run().
bool ServerFramework::Initialize()
{
mIOService.run(); // <-- you don't check the return value here
StartAccept();
return true;
}
it will return the number of handlers executed, I suspect it is zero. Try invoking it after async_accept()
bool ServerFramework::Initialize()
{
StartAccept();
mIOService.run();
return true;
}
Though, it isn't entirely obvious by your limited code snippets where you invoke ServerFramework::Initialize(). I suggest editing your question with a short, self contained, correct example that we can compile with little to no effort. Your current code will not compile without additional boilerplate stuff, like main().

boost::asio::async_read_until problem

I'm trying to modify the echo server example from boost asio and I'm running into problem when I try to use boost::asio::async_read_until. Here's the code:
#include <cstdlib>
#include <iostream>
#include <boost/bind.hpp>
#include <boost/asio.hpp>
using boost::asio::ip::tcp;
class session
{
public:
session(boost::asio::io_service& io_service)
: socket_(io_service)
{
}
tcp::socket& socket()
{
return socket_;
}
void start()
{
std::cout<<"starting"<<std::endl;
boost::asio::async_read_until(socket_, boost::asio::buffer(data_, max_length), ' ',
boost::bind(&session::handle_read, this,
boost::asio::placeholders::error,
boost::asio::placeholders::bytes_transferred));
}
void handle_read(const boost::system::error_code& error,
size_t bytes_transferred)
{
std::cout<<"handling read"<<std::endl;
if (!error)
{
boost::asio::async_write(socket_,
boost::asio::buffer(data_, bytes_transferred),
boost::bind(&session::handle_write, this,
boost::asio::placeholders::error));
}
else
{
delete this;
}
}
void handle_write(const boost::system::error_code& error)
{
if (!error)
{
/*
socket_.async_read_some(boost::asio::buffer(data_, max_length),
boost::bind(&session::handle_read, this,
boost::asio::placeholders::error,
boost::asio::placeholders::bytes_transferred));
*/ }
else
{
delete this;
}
}
private:
tcp::socket socket_;
enum { max_length = 1024 };
char data_[max_length];
};
class server
{
public:
server(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(&server::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(&server::handle_accept, this, new_session,
boost::asio::placeholders::error));
}
else
{
delete new_session;
}
}
private:
boost::asio::io_service& io_service_;
tcp::acceptor acceptor_;
};
int main(int argc, char* argv[])
{
try
{
if (argc != 2)
{
std::cerr << "Usage: async_tcp_echo_server <port>\n";
return 1;
}
boost::asio::io_service io_service;
using namespace std; // For atoi.
server s(io_service, atoi(argv[1]));
io_service.run();
}
catch (std::exception& e)
{
std::cerr << "Exception: " << e.what() << "\n";
}
return 0;
}
The problem is when I try to compile I get this weird error:
server.cpp: In member function ‘void session::start()’:
server.cpp:27: error: no matching function for call to ‘async_read_until(boost::asio::basic_stream_socket >&, boost::asio::mutable_buffers_1, char, boost::_bi::bind_t, boost::_bi::list3, boost::arg<1> ()(), boost::arg<2> ()()> >)’
Can someone please explain what's going on? From what I can tell the arguments to async_read_until are correct.
Thanks!
The second argument of async_read_until should be a streambuf object into which the data will be read. To put it simple, you need to pass a boost::asio::streambuf by reference, not a boost::asio::buffer by value.
There is no need to use streambufs. There are overloads that accept dynamic buffers. Dynamic is key since read_until implies the need for a buffer that can increase its size at the callee's discretion. Therefore, all you need is to replace the call to boost::asio::buffer with boost::asio::dynamic_buffer and call it on either std::string or std::vector<char>.
...
void start()
{
std::cout<<"starting"<<std::endl;
boost::asio::async_read_until(
socket_, boost::asio::dynamic_buffer(data_), ' ',
boost::bind(&session::handle_read, this,
boost::asio::placeholders::error,
boost::asio::placeholders::bytes_transferred));
}
...
private:
tcp::socket socket_;
std::string data_;
// or
//std::vector<char> data_;
};
I would also get rid of boost::bind since it's an overkill and use a lambda (use them as much as you can)
[this](const boost::system::error_code& error, size_t bytes_transferred) {
handle_read(error, bytes_transferred);
}
const (in)correctness may also cause this type of error message.