Wt

refresh Wt application in browser(or reenter the http address in address bar) will cause server side crash.

i think i'v found the reason:

learn this code fragment in WebControl.C

void WebController::handleAsyncRequest(WebRequest *request)
{
  ...
#ifdef WT_THREADED
  boost::recursive_mutex::scoped_lock sessionsLock(mutex_);
#endif
  ...

  bool sessionDead = false;
  {
    WebSession::Handler handler(*session, *request, *(WebResponse *)request);

#ifdef WT_THREADED
    sessionsLock.unlock();
#endif

    session->handleRequest(handler);
    sessionDead = handler.sessionDead();
  }                                         //in Handler::~Handler() session will be delete 

  ...                                       //state without lock 
                                            //DANGEROUS MOMENT !!!!!!!!!!!!!!!!!!!!!!!!!!!
                                            //the deleted session will be accessed in other thread

  if (sessionDead)                          
    removeSession(sessionId);               //lock/unlock mutex_

  if (!running_)
    expireSessions();                       //lock/unlock mutex_

  ...
} 

in multi-thread enviroment

other thread will enter funciton expireSessions()

and access the deleted session that still in the SessionMap

when this thread unlock the mutex_

the crash happened

i'v test some examples with buildin http under windows,

the incidence rate is rather high

i try to change the code:

void WebController::handleAsyncRequest(WebRequest *request)
{
  ...
#ifdef WT_THREADED
  boost::recursive_mutex::scoped_lock sessionsLock(mutex_);
#endif
  ...

  bool sessionDead = false;
  {
    WebSession::Handler handler(*session, *request, *(WebResponse *)request);

    session->handleRequest(handler);
    sessionDead = handler.sessionDead();
  }                                         

  if (sessionDead)                          
    removeSession_WITHOUT_LOCK(sessionId);               

#ifdef WT_THREADED
    sessionsLock.unlock();
#endif

  if (!running_)
    expireSessions();                       //lock/unlock mutex_

  ...
} 


//add low level version of removeSession
void WebController::removeSession_WITHOUT_LOCK(const std::string& sessionId)
{
  SessionMap::iterator i = sessions_.find(sessionId);
  if (i != sessions_.end())
    sessions_.erase(i);
}

void WebController::removeSession(const std::string& sessionId)
{
#ifdef WT_THREADED
  boost::recursive_mutex::scoped_lock sessionsLock(mutex_);
#endif // WT_THREADED

  removeSession_WITHOUT_LOCK(sessionId);
}

main idea is unlock mutex_ AFTER the deleted session removed from sessionMap.

after i change the code, the crash never happened

but i don't know whether the problem is solved completely.

i wait your real solution