boost::asio doesn't work - boost

Question

With the following class
the header:
namespace msgSrv {
class endPoint {
public:
asio::ip::udp::endpoint ep;
endPoint(std::string ip, int port);
};
class msgSrv {
private:
asio::ip::udp::socket *asioSocket;
asio::io_service *asioIoService;
int listenPort;
boost::array<char, 1> rcvBuff;
asio::ip::udp::endpoint lastRcvdPcktEndp;
char * sbuff;
public:
boost::condition_variable cond;
boost::mutex mut;
msgSrv(int listenPort);
virtual ~msgSrv();
void start();
void pckRcvd(const asio::error_code& error, std::size_t bytes_transferred);
void sendTo(const char* buff, int len, endPoint ep);
void sendHnd(const asio::error_code& error, std::size_t bytes_transferred);
};
}
the .cpp
#include "msgSrv.h"
namespace msgSrv {
endPoint::endPoint(const std::string ip, int port) {
asio::ip::address addr = asio::ip::address::from_string(ip);
ep = asio::ip::udp::endpoint(addr, port);
}
msgSrv::msgSrv(int listenPort) {
// TODO Auto-generated constructor stub
this->listenPort = listenPort;
try {
asioIoService = new asio::io_service();
asioSocket = new asio::ip::udp::socket(*asioIoService,
asio::ip::udp::endpoint(asio::ip::udp::v4(), listenPort)); //new asio::ip::udp::socket_(*asioIoService, udp::endpoint(udp::v4(), listenPort));
} catch (std::exception &e) {
std::cerr << "Error initializing ioservice or socket:" << e.what();
}
asioIoService->run();
}
msgSrv::~msgSrv() {
// TODO Auto-generated destructor stub
delete asioIoService;
delete asioSocket;
}
void msgSrv::start() {
asioSocket->async_receive_from(asio::buffer(rcvBuff), lastRcvdPcktEndp,
boost::bind(&msgSrv::pckRcvd, this, asio::placeholders::error,
asio::placeholders::bytes_transferred));
}
void msgSrv::pckRcvd(const asio::error_code& error,
std::size_t bytes_transferred) {
std::cout << "Rcvd! " << lastRcvdPcktEndp.address().to_string() << ":"
<< lastRcvdPcktEndp.port() << "\n";
}
void msgSrv::sendTo(const char* buff, int len, endPoint ep) {
sbuff = new char[len];
mempcpy(sbuff, buff, len);
asioSocket->async_send_to(asio::buffer(sbuff, len), ep.ep, boost::bind(
&msgSrv::sendHnd, this, asio::placeholders::error,
asio::placeholders::bytes_transferred));
}
void msgSrv::sendHnd(const asio::error_code& error,
std::size_t bytes_transferred) {
std::cout << "Snt!\n";
delete sbuff;
}
}
and the following "main" file:
int main()
{
msgSrv::msgSrv aa(4450);
aa.start();
msgSrv::endPoint ep("127.0.0.1", 4450);
std::string a("Prova!");
int len = a.length();
aa.sendTo(a.c_str(), len, ep);
std::cout << "sent...\n";
std::cout << "notified...\n";
}
all I get is:
terminate called after throwing an instance of 'asio::system_error'
what(): mutex: Invalid argument
sent...
notified...
What's wrong?? I tried even to put a while(1) in the main, to see if something happens... I even tried to put a condition in the main that is unlocked by the receive handler... all remains locked... So what??? No idea!

Answer 1

I don't see you actually locking any muxtex, so that error is strange.
However your problem is to calling asioIoService->run() inside the constructor, witch fall in infinite loop. The solution is to create a new boost::thread, witch call asioIoService->run() itself. This thread will be processing all jobs. You may also call asio::io_service::run() with more then one thread, to get processing on more then one job at the same time.
m_thread = new boost::thread(boost::bind(&asio::io_service::run,asioIoService));
Calling asioIoService->stop() will force exit of asio::io_service::run(), thus closing the thread. You must join this thread to ensure that thread terminates before destroying asioIoService pointer in the destructor of your msgSrv class.