From 24d26e802a841decd2865517edbfb233717da155 Mon Sep 17 00:00:00 2001
From: Thorsten Kollegger <t.kollegger@gsi.de>
Date: Sat, 26 Apr 2014 10:11:39 +0000
Subject: [PATCH] Using boost::msm inside FairMQStateMachine.

---
 fairmq/FairMQStateMachine.cxx | 183 +++++----------------------
 fairmq/FairMQStateMachine.h   | 224 +++++++++++++++++++++++++++++++---
 2 files changed, 236 insertions(+), 171 deletions(-)

diff --git a/fairmq/FairMQStateMachine.cxx b/fairmq/FairMQStateMachine.cxx
index a5ab4282..04516b18 100644
--- a/fairmq/FairMQStateMachine.cxx
+++ b/fairmq/FairMQStateMachine.cxx
@@ -5,166 +5,43 @@
  * @author D. Klein, A. Rybalchenko
  */
 
-#include <boost/bind.hpp>
-#include <boost/thread.hpp>
-
 #include "FairMQStateMachine.h"
 #include "FairMQLogger.h"
 
-
-FairMQStateMachine::FairMQStateMachine() :
-  fState(IDLE)
-{
-}
-
-void FairMQStateMachine::ChangeState(int event)
-{
-  switch(fState) {
-
-  case IDLE:
-    switch(event) {
-
-    case INIT:
-      LOG(STATE) << "IDLE --init--> INITIALIZING";
-      fState = INITIALIZING;
-      Init();
-      return;
-
-    case END:
-      LOG(STATE) << "IDLE --end--> (o)";
-      return;
-
-    default:
-      return;
-    }
-    break;
-
-
-  case INITIALIZING:
-    switch(event) {
-
-    case SETOUTPUT:
-      LOG(STATE) << "INITIALIZING --bind--> SETTINGOUTPUT";
-      fState = SETTINGOUTPUT;
-      InitOutput();
-      return;
-
-    default:
-      return;
-    }
-    break;
-
-
-  case SETTINGOUTPUT:
-    switch(event) {
-
-    case SETINPUT:
-      LOG(STATE) << "SETTINGOUTPUT --connect--> SETTINGINPUT";
-      fState = SETTINGINPUT;
-      InitInput();
-      return;
-
-    default:
-      return;
-    }
-    break;
-
-
-  case SETTINGINPUT:
-    switch(event) {
-
-    case PAUSE:
-      LOG(STATE) << "SETTINGINPUT --pause--> WAITING";
-      fState = WAITING;
-      Pause();
-      return;
-
-    case RUN:
-      LOG(STATE) << "SETTINGINPUT --run--> RUNNING";
-      fState = RUNNING;
-      running_state = boost::thread(boost::bind(&FairMQStateMachine::Run, this));
-      return;
-
-    default:
-      return;
-    }
-    break;
-
-
-  case WAITING:
-    switch(event) {
-
-    case RUN:
-      LOG(STATE) << "WAITING --run--> RUNNING";
-      fState = RUNNING;
-      running_state = boost::thread(boost::bind(&FairMQStateMachine::Run, this));
-      return;
-
-    case STOP:
-      LOG(STATE) << "WAITING --stop--> IDLE";
-      fState = IDLE;
-      Shutdown();
-      return;
-
-    default:
-      return;
-    }
-    break;
-
-
-  case RUNNING:
-    switch(event) {
-
-    case PAUSE:
-      LOG(STATE) << "RUNNING --pause--> WAITING";
-      fState = WAITING;
-      running_state.join();
-      return;
-
-    case STOP:
-      LOG(STATE) << "RUNNING --stop--> IDLE";
-      fState = IDLE;
-      running_state.join();
-      Shutdown();
-      return;
-
-    default:
-      return;
-    }
-    break;
-
-
-  default:
-    break;
-
-  }//switch fState
-}
-
-void FairMQStateMachine::Init()
-{
-}
-
-void FairMQStateMachine::Run()
-{
-}
-
-void FairMQStateMachine::Pause()
-{
-}
-
-void FairMQStateMachine::Shutdown()
-{
-}
-
-void FairMQStateMachine::InitOutput()
-{
-}
-
-void FairMQStateMachine::InitInput()
+FairMQStateMachine::FairMQStateMachine()
 {
+    start();
 }
 
 FairMQStateMachine::~FairMQStateMachine()
 {
+    stop();
 }
 
+void FairMQStateMachine::ChangeState(int event)
+{
+    switch (event)
+    {
+        case INIT:
+            process_event(FairMQFSM::INIT());
+            return;
+        case SETOUTPUT:
+            process_event(FairMQFSM::SETOUTPUT());
+            return;
+        case SETINPUT:
+            process_event(FairMQFSM::SETINPUT());
+            return;
+        case RUN:
+            process_event(FairMQFSM::RUN());
+            return;
+        case PAUSE:
+            process_event(FairMQFSM::PAUSE());
+            return;
+        case STOP:
+            process_event(FairMQFSM::STOP());
+            return;
+        case END:
+            process_event(FairMQFSM::END());
+            return;
+    }
+}
diff --git a/fairmq/FairMQStateMachine.h b/fairmq/FairMQStateMachine.h
index 2cd015be..70177663 100644
--- a/fairmq/FairMQStateMachine.h
+++ b/fairmq/FairMQStateMachine.h
@@ -9,31 +9,219 @@
 #define FAIRMQSTATEMACHINE_H_
 
 #include <boost/thread.hpp>
+#include <boost/bind.hpp>
+#include <boost/msm/back/state_machine.hpp>
+#include <boost/msm/front/state_machine_def.hpp>
+#include <boost/msm/front/functor_row.hpp>
+#include <boost/msm/front/euml/common.hpp>
+#include <boost/msm/front/euml/operator.hpp>
+#include <boost/function.hpp>
 
+#include "FairMQLogger.h"
 
-class FairMQStateMachine
+namespace msm = boost::msm;
+namespace mpl = boost::mpl;
+namespace msmf = boost::msm::front;
+
+namespace FairMQFSM
+{
+    // defining events for the boost MSM state machine
+    struct INIT
+    {
+    };
+    struct SETOUTPUT
+    {
+    };
+    struct SETINPUT
+    {
+    };
+    struct PAUSE
+    {
+    };
+    struct RUN
+    {
+    };
+    struct STOP
+    {
+    };
+    struct END
+    {
+    };
+
+    // defining the boost MSM state machine
+    struct FairMQFSM_ : public msm::front::state_machine_def<FairMQFSM_>
+    {
+        template <class Event, class FSM>
+        void on_entry(Event const&, FSM&)
+        {
+            LOG(STATE) << "Entering FairMQ state machine";
+            fState = IDLE;
+        }
+        template <class Event, class FSM>
+        void on_exit(Event const&, FSM&)
+        {
+            LOG(STATE) << "Exiting FairMQ state machine";
+        }
+        // The list of FSM states
+        struct IDLE_FSM : public msm::front::state<>
+        {
+        };
+        struct INITIALIZING_FSM : public msm::front::state<>
+        {
+        };
+        struct SETTINGOUTPUT_FSM : public msm::front::state<>
+        {
+        };
+        struct SETTINGINPUT_FSM : public msm::front::state<>
+        {
+        };
+        struct WAITING_FSM : public msm::front::state<>
+        {
+        };
+        struct RUNNING_FSM : public msm::front::state<>
+        {
+        };
+        // Define initial state
+        typedef IDLE_FSM initial_state;
+        // Actions
+        struct TestFct
+        {
+            template <class EVT, class FSM, class SourceState, class TargetState>
+            void operator()(EVT const&, FSM&, SourceState&, TargetState&)
+            {
+                LOG(STATE) << "Transition from " << typeid(SourceState).name() << " to " << typeid(TargetState).name() << " with event:" << typeid(EVT).name();
+            }
+        };
+        struct InitFct
+        {
+            template <class EVT, class FSM, class SourceState, class TargetState>
+            void operator()(EVT const&, FSM& fsm, SourceState&, TargetState&)
+            {
+                fsm.fState = INITIALIZING;
+                fsm.Init();
+            }
+        };
+        struct SetOutputFct
+        {
+            template <class EVT, class FSM, class SourceState, class TargetState>
+            void operator()(EVT const&, FSM& fsm, SourceState&, TargetState&)
+            {
+                fsm.fState = SETTINGOUTPUT;
+                fsm.InitOutput();
+            }
+        };
+        struct SetInputFct
+        {
+            template <class EVT, class FSM, class SourceState, class TargetState>
+            void operator()(EVT const&, FSM& fsm, SourceState&, TargetState&)
+            {
+                fsm.fState = SETTINGINPUT;
+                fsm.InitInput();
+            }
+        };
+        struct RunFct
+        {
+            template <class EVT, class FSM, class SourceState, class TargetState>
+            void operator()(EVT const&, FSM& fsm, SourceState&, TargetState&)
+            {
+                fsm.fState = RUNNING;
+                fsm.running_state = boost::thread(boost::bind(&FairMQFSM_::Run, &fsm));
+            }
+        };
+        struct StopFct
+        {
+            template <class EVT, class FSM, class SourceState, class TargetState>
+            void operator()(EVT const&, FSM& fsm, SourceState&, TargetState&)
+            {
+                fsm.fState = IDLE;
+                fsm.running_state.join();
+                fsm.Shutdown();
+            }
+        };
+        struct PauseFct
+        {
+            template <class EVT, class FSM, class SourceState, class TargetState>
+            void operator()(EVT const&, FSM& fsm, SourceState&, TargetState&)
+            {
+                fsm.fState = WAITING;
+                fsm.running_state.join();
+                fsm.Pause();
+            }
+        };
+        // actions to be overwritten by derived classes
+        virtual void Init()
+        {
+        }
+        virtual void Run()
+        {
+        }
+        virtual void Pause()
+        {
+        }
+        virtual void Shutdown()
+        {
+        }
+        virtual void InitOutput()
+        {
+        }
+        virtual void InitInput()
+        {
+        }
+        // Transition table for FairMQFMS
+        struct transition_table : mpl::vector<
+                                      //    Start     Event     Next    Action    Guard
+                                      //  +---------+---------+-------+---------+--------+
+                                      msmf::Row<IDLE_FSM, INIT, INITIALIZING_FSM, InitFct, msmf::none>,
+                                      msmf::Row<IDLE_FSM, END, msmf::none, TestFct, msmf::none>, // this is an invalid transition...
+                                      msmf::Row<INITIALIZING_FSM, SETOUTPUT, SETTINGOUTPUT_FSM, SetOutputFct, msmf::none>,
+                                      msmf::Row<SETTINGOUTPUT_FSM, SETINPUT, SETTINGINPUT_FSM, SetInputFct, msmf::none>,
+                                      msmf::Row<SETTINGINPUT_FSM, PAUSE, WAITING_FSM, PauseFct, msmf::none>,
+                                      msmf::Row<SETTINGINPUT_FSM, RUN, RUNNING_FSM, RunFct, msmf::none>,
+                                      msmf::Row<WAITING_FSM, RUN, RUNNING_FSM, RunFct, msmf::none>,
+                                      msmf::Row<WAITING_FSM, STOP, IDLE_FSM, StopFct, msmf::none>,
+                                      msmf::Row<RUNNING_FSM, PAUSE, WAITING_FSM, PauseFct, msmf::none>,
+                                      msmf::Row<RUNNING_FSM, STOP, IDLE_FSM, StopFct, msmf::none> >
+        {
+        };
+        // Replaces the default no-transition response.
+        template <class FSM, class Event>
+        void no_transition(Event const& e, FSM&, int state)
+        {
+            LOG(STATE) << "no transition from state " << state << " on event " << typeid(e).name() << std::endl;
+        }
+        // this is to run certain functions (e.g. Run()) as separate task
+        boost::thread running_state;
+        // backward compatibility to FairMQStateMachine
+        enum State
+        {
+            IDLE,
+            INITIALIZING,
+            SETTINGOUTPUT,
+            SETTINGINPUT,
+            WAITING,
+            RUNNING
+        };
+        State fState;
+    };
+    typedef msm::back::state_machine<FairMQFSM_> FairMQFSM;
+}
+
+class FairMQStateMachine : public FairMQFSM::FairMQFSM
 {
   public:
-    enum State {
-      IDLE, INITIALIZING, SETTINGOUTPUT, SETTINGINPUT, WAITING, RUNNING
-    };
-    enum Event {
-      INIT, SETOUTPUT, SETINPUT, PAUSE, RUN, STOP, END
+    enum Event
+    {
+        INIT,
+        SETOUTPUT,
+        SETINPUT,
+        PAUSE,
+        RUN,
+        STOP,
+        END
     };
     FairMQStateMachine();
-    void ChangeState(int event);
     virtual ~FairMQStateMachine();
-
-  protected:
-    State fState;
-    Event fEvent;
-    virtual void Init();
-    virtual void Run();
-    virtual void Pause();
-    virtual void Shutdown();
-    virtual void InitOutput();
-    virtual void InitInput();
-    boost::thread running_state;
+    void ChangeState(int event);
 };
 
 #endif /* FAIRMQSTATEMACHINE_H_ */