[Boost-users] [Thread] join_all and interrupt_all playing together

21 Oct 2009


      I'm trying to set several threads running and have the main thread 
signal an interrupt.  I've included an example that shows what I'm 
trying to accomplish.  The threads that are created are associated with 
thread_group and then a join_all is called.  I would expect the main 
thread to be able to call interrupt_all on the thread_group.  Since this 
wasn't working I looked at what the join_all and interrupt_all function 
were actually doing.  It turns out that thread_group has a mutex that is 
being called for each function and since the mutex for join_all is in 
use, the lock in interrupt_all is blocking.  I understand why the mutex 
is there but am unclear how interrupt_all is suppose to work with 
join_all.  To accomplish the functionality I need I have to use 
create_thread and store the return pointer in a list of my own.  Then 
call interrupt on each pointer I stored.  Which is basically duplicating 
the storage of thread_group.  This seem like a waste.  I would 
appreciate any advice.

Ryan

class Converter
{
public:
  Converter(void)  {
    m_Threads.reset(new boost::thread_group);
  }

  void run(void)  {
    m_Threads->add_thread(new 
boost::thread(boost::bind(&Converter::processSureTrakMessage, this)));
    
//m_Threads_v.push_back(m_Threads->create_thread(boost::bind(&Converter::processSureTrakMessage, 
this)));
    m_Threads->join_all();
    m_Threads.reset(new boost::thread_group);
  }

  void stop(void)  {
    //for (std::vector::iterator iter = 
m_Threads_v.begin(); iter != m_Threads_v.end(); ++iter) {
    //  (*iter)->interrupt();
    //}
    m_Threads->interrupt_all();
  }

  void processMessage(void) {
    try {
      for (;;) {
        boost::this_thread::interruption_point();
      }
    }
    catch (...) {
      int bob = 1;
    }
    int bobo = 2;
  }

private:
  boost::scoped_ptrboost::thread_group            m_Threads;
  boost::scoped_ptrboost::thread                       
m_IO_Service_Thread;
  std::vector                                m_Threads_v;

};

boost::function console_ctrl_function;

BOOL WINAPI console_ctrl_handler(DWORD ctrl_type) {
  switch (ctrl_type) {
    case CTRL_C_EVENT:
    case CTRL_BREAK_EVENT:
    case CTRL_CLOSE_EVENT:
    case CTRL_SHUTDOWN_EVENT:
      console_ctrl_function();
      return TRUE;
    default:
      return FALSE;
  }
}

int main(int argc, char * argv[]) {
  Converter   convert;
  console_ctrl_function = boost::bind(&Converter::stop, &convert);
  SetConsoleCtrlHandler(console_ctrl_handler, TRUE);

  convert.run();
 
  return 0;
}

[Boost-users] [Thread] join_all and interrupt_all playing together

Ryan McConnehey