Utils: Add singleton alive test member

[senf.git] / Scheduler / FIFORunner.hh

diff --git a/Scheduler/FIFORunner.hh b/Scheduler/FIFORunner.hh
index 3ad8d7e..756f07f 100644 (file)
--- a/Scheduler/FIFORunner.hh
+++ b/Scheduler/FIFORunner.hh
@@ -27,20 +27,32 @@
 #define HH_FIFORunner_ 1
 
 // Custom includes
+#include <signal.h>
 #include <boost/utility.hpp>
 #include "../boost/intrusive/ilist.hpp"
 #include "../boost/intrusive/ilist_hook.hpp"
+#include "../Utils/singleton.hh"
 
 //#include "FIFORunner.mpp"
 ///////////////////////////////hh.p////////////////////////////////////////
 
 namespace senf { 
+
+    class Scheduler;
+
 namespace scheduler {
 
-    /** \brief
+    /** \brief Task execution scheduler
+
+        The FIFORunner implements a simple FIFO scheduler for callback tasks. All tasks are held in
+        a queue. Whenever a task is run, it is moved to the end of the queue. Running the queue will
+        run all tasks which have been marked runnable. 
+
+        When running a task, it's runnable flag is always reset. The flag is set whenever an event
+        is posted for the task.
       */
     class FIFORunner
-        : boost::noncopyable
+        : public singleton<FIFORunner>
     {
     public:
         struct TaskInfo;
@@ -48,42 +60,79 @@ namespace scheduler {
     private:
         struct TaskListTag;
         typedef boost::intrusive::ilist_base_hook<TaskListTag> TaskListBase;
-        typedef TaskListBase::value_traits<TaskInfo> TaskListType;
-        typedef boost::intrusive::ilist<TaskListType, false> TaskList;
+        typedef boost::intrusive::ilist<TaskListBase::value_traits<TaskInfo>, false> TaskList;
 
     public:
         ///////////////////////////////////////////////////////////////////////////
         // Types
 
+        /** \brief Task structure
+
+            TaskInfo is the base-class for all tasks.
+         */
         struct TaskInfo 
             : public TaskListBase
         {
             TaskInfo();
             virtual ~TaskInfo();
 
-            bool runnable;
-            virtual void run() = 0;
+            bool runnable;              ///< Runnable flag
+                                        /**< This must be set to \c true when the task is
+                                             runnable. It is reset automatically when the task is
+                                             run. */
+
+            std::string name;           ///< Descriptive task name
+#       ifdef SENF_DEBUG
+            std::string backtrace;
+#       endif
+            virtual void run() = 0;     ///< Called to run the task
         };
 
         ///////////////////////////////////////////////////////////////////////////
         ///\name Structors and default members
         ///@{
 
-        FIFORunner();
+        using singleton<FIFORunner>::instance;
+        using singleton<FIFORunner>::alive;
 
         ///@}
         ///////////////////////////////////////////////////////////////////////////
 
-        void enqueue(TaskInfo * task);
-        void dequeue(TaskInfo * task);
+        void enqueue(TaskInfo * task);  ///< Add task to queue
+        void dequeue(TaskInfo * task);  ///< Remove task from queue
         
-        void run();
+        void run();                     ///< Run queue
+
+        void taskTimeout(unsigned ms);  ///< Set task timeout to \a ms milliseconds
+        unsigned taskTimeout() const;   ///< Get task timeout in milliseconds
+
+        unsigned hangCount() const;     ///< Number of task expirations
+                                        /**< The FIFORunner manages a watchdog which checks, that a
+                                             single task does not run continuously for a longer time
+                                             or block. If a task runs for more than 1s, a warning is
+                                             printed  and the hangCount is increased. */
 
     protected:
 
     private:
+        FIFORunner();
+        ~FIFORunner();
+
+        static void watchdog(int, siginfo_t *, void *);
+
         TaskList tasks_;
         TaskList::iterator next_;
+        timer_t watchdogId_;
+        unsigned watchdogMs_;
+        std::string runningName_;
+#   ifdef SENF_DEBUG
+        std::string runningBacktrace_;
+#   endif
+        unsigned watchdogCount_;
+        unsigned hangCount_;
+
+        friend class singleton<FIFORunner>;
+        friend class senf::Scheduler;
     };