trick/trick_source/sim_services/VariableServer/VariableServerSessionThread_loop.cpp

#include <iostream>
#ifdef __linux
#include <cxxabi.h>
#endif

#include "trick/VariableServer.hh"
#include "trick/message_proto.h"
#include "trick/realtimesync_proto.h"
#include "trick/ExecutiveException.hh"
#include "trick/exec_proto.h"

#include "trick/VariableServerSessionThread.hh"

void exit_var_thread(void *in_vst) ;

void * Trick::VariableServerSessionThread::thread_body() {

    // Check for short running sims
    test_shutdown(NULL, NULL);

    //  We need to make the thread to VariableServerSessionThread map before we accept the connection.
    //  Otherwise we have a race where this thread is unknown to the variable server and the
    //  client gets confirmation that the connection is ready for communication.
    _vs->add_vst( pthread_self() , this ) ;

    // Accept client connection
    int status = _connection->start();

    if (status != 0) {
        _vs->delete_vst(pthread_self());

        // Tell main thread that we failed to initialize
        pthread_mutex_lock(&_connection_status_mutex);
        _connection_status = CONNECTION_FAIL;
        pthread_cond_signal(&_connection_status_cv);
        pthread_mutex_unlock(&_connection_status_mutex);

        thread_shutdown();
    }

    // if log is set on for variable server (e.g., in input file), turn log on for each client
    if (_vs->get_log()) {
        _session->set_log(true);
    }

    if (_vs->get_session_log()) {
        _session->set_session_log(true);
    }

    if (_vs->get_info_msg()) {
        _session->set_info_message(true);
    }

    // Give the initialized connection to the session
    // Don't touch the connection anymore until we shut them both down
    _session->set_connection(_connection);
    _vs->add_session( pthread_self(), _session );

    // Tell main that we are ready
    pthread_mutex_lock(&_connection_status_mutex);
    _connection_status = CONNECTION_SUCCESS;
    pthread_cond_signal(&_connection_status_cv);
    pthread_mutex_unlock(&_connection_status_mutex);

    try {
        while (1) {
            // Shutdown here if it's time
            test_shutdown(exit_var_thread, (void *) this);

            // Pause here if we are in a restart condition
            test_pause();

            // Look for a message from the client
            // Parse and execute if one is availible
            int read_status = _session->handle_message();
            if ( read_status < 0 ) {
                break ;
            }

            // Check to see if exit is necessary
            if (_session->get_exit_cmd() == true) {
                break;
            }

            // Tell session it's time to copy and write if the mode is correct
            int ret =_session->copy_and_write_async(); 
            if (ret < 0) {
                break;
            }

            // Sleep for the appropriate cycle time
            usleep((unsigned int) (_session->get_update_rate() * 1000000));
        }
    } catch (Trick::ExecutiveException & ex ) {
        message_publish(MSG_ERROR, "\nVARIABLE SERVER COMMANDED exec_terminate\n  ROUTINE: %s\n  DIAGNOSTIC: %s\n" ,
         ex.file.c_str(), ex.message.c_str()) ;

        exec_signal_terminate();

    } catch (const std::exception &ex) {
        message_publish(MSG_ERROR, "\nVARIABLE SERVER caught std::exception\n  DIAGNOSTIC: %s\n" ,
         ex.what()) ;
        
        exec_signal_terminate();

#ifdef __linux
#ifdef __GNUC__
#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 2
    // for post gcc 4.1.2 or whatever glibc version is used in RHEL6 and above.
    } catch (abi::__forced_unwind&) {
        //pthread_exit and pthread_cancel will cause an abi::__forced_unwind to be thrown. Rethrow it.
        throw;
#endif
#endif
#endif
    } catch (...) {
#ifdef __linux
#ifdef __GNUC__
#if (__GNUC__ == 4 && __GNUC_MINOR__ == 1) || __GNUC__ == 12
        // for gcc 4.1.2 or whatever glib version in RHEL 5 that does not work with the abi::__forced_unwind
        // Also seems to have a problem with gcc 12
        throw;
#else
        message_publish(MSG_ERROR, "\nVARIABLE SERVER caught unknown exception\n" ) ;
        exec_signal_terminate();
#endif
#endif
#endif
    }

    if (_debug >= 3) {
        message_publish(MSG_DEBUG, "%p tag=<%s> var_server receive loop exiting\n", _connection, _connection->getClientTag().c_str());
    }

    thread_shutdown(exit_var_thread, this);
    // No return from this.
}