Re: [Boost-users] [asio] creating acceptor on the stack causes seg-fault

Subject: Re: [Boost-users] [asio] creating acceptor on the stack causes seg-fault
From: Steve Lorimer (steve.lorimer_at_[hidden])
Date: 2010-07-16 06:45:31

D'oh! Sorry, I'm super lame - have to init the io_service object BEFORE you
pass it to the acceptor! Change the order of declaration in the class and no
seg-fault! :)

On 16 July 2010 11:16, Steve Lorimer <steve.lorimer_at_[hidden]> wrote:

> Hi folks, I have the following class:
>
>  using namespace boost::asio;
>
> // basic tcp server
> class server
> {
>     boost::thread thread;
>     ip::tcp::acceptor acceptor;
>     io_service io_svc;
>
>     // tcp_srv_conn object which will become the local end-point of the
> next incoming connection
>     tcp_srv_conn_p new_conn;
>
>     void loop(unsigned short port);
>     void on_accept(const boost::system::error_code &err);
>
> public:
>     server();
>     virtual ~server();
>
>     void serve(unsigned short port);
>     void serve(const std::string &svc);
>     void close();
> };
>
>
> and the constructor for server looks like this:
>
> server::server() :
> acceptor(io_svc),
>  new_conn(new tcp_srv_conn(io_svc))
> { }
>
>
> If I create a server object on the stack:
>
> server s;
>
>
> I get a segmentation fault deep inside the asio internals (something to do
> with a mutex), originating from initialising acceptor with my io_service
> object: acceptor(io_svc)
>
> Here is a stack trace of the core file:
> Marked in red is (#6) my server constructor and (#7) the
> basic_socket_acceptor constructor
>
> Core was generated by `tcp_srv.debug -p 12'.
> Program terminated with signal 11, Segmentation fault.
> #0  0x00007f8de6c3ed21 in pthread_mutex_lock () from /lib64/libpthread.so.0
> (gdb) backtrace
> #0  0x00007f8de6c3ed21 in pthread_mutex_lock () from /lib64/libpthread.so.0
> #1  0x0000000000421153 in boost::asio::detail::posix_mutex::lock (this=0x8)
> at /usr/include/boost/asio/detail/posix_mutex.hpp:71
> #2  0x0000000000422db7 in scoped_lock (this=0x7f8de58d7a70, m=...) at
> /usr/include/boost/asio/detail/scoped_lock.hpp:36
> #3  0x0000000000426e22 in
> boost::asio::detail::service_registry::use_service<boost::asio::socket_acceptor_service<boost::asio::ip::tcp>
> > (this=0x0) at /usr/include/boost/asio/detail/service_registry.hpp:94
> #4  0x000000000042573a in
> boost::asio::use_service<boost::asio::socket_acceptor_service<boost::asio::ip::tcp>
> > (ios=...) at /usr/include/boost/asio/impl/io_service.ipp:195
> #5  0x000000000042427d in basic_io_object (this=0x7f8de58d7bd0,
> io_service=...) at /usr/include/boost/asio/basic_io_object.hpp:72
> #6  0x0000000000422fd7 in basic_socket_acceptor (this=0x7f8de58d7bd0,
> io_service=...) at /usr/include/boost/asio/basic_socket_acceptor.hpp:77
> #7  0x000000000041fe63 in server (this=0x7f8de58d7b90) at src/tcp_srv.cpp:9
> #8  0x000000000040d4d2 in app::start_here (this=0x7fffaab13b2f, ac=3,
> av=0x7fffaab13cd8) at test/server_test.cpp:65
>
>
> Am I doing something stupid? How should I be creating my io_service and
> acceptor objects?
>
> TIA
> Steve
>
>
>