include/vcl/task.hxx

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  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #ifndef INCLUDED_VCL_TASK_HXX
  21 #define INCLUDED_VCL_TASK_HXX
  22
  23 #include <vcl/dllapi.h>
  24
  25 struct ImplSchedulerData;
  26
  27 enum class TaskPriority
  28 {
  29     HIGHEST,       ///< These events should run very fast!
  30     DEFAULT,       ///< Default priority used, e.g. the default timer priority
  31     HIGH_IDLE,     ///< Important idle events to be run before processing drawing events
  32     RESIZE,        ///< Resize runs before repaint, so we won't paint twice
  33     REPAINT,       ///< All repaint events should go in here
  34     POST_PAINT,    ///< Everything running directly after painting
  35     DEFAULT_IDLE,  ///< Default idle priority
  36     LOWEST         ///< Low, very idle cleanup tasks
  37 };
  38
  39 #define PRIO_COUNT (static_cast<int>(TaskPriority::LOWEST) + 1)
  40
  41 class VCL_DLLPUBLIC Task
  42 {
  43     friend class Scheduler;
  44     friend struct ImplSchedulerData;
  45
  46     ImplSchedulerData *mpSchedulerData; ///< Pointer to the element in scheduler list
  47     const sal_Char    *mpDebugName;     ///< Useful for debugging
  48     TaskPriority       mePriority;      ///< Task priority
  49     bool               mbActive;        ///< Currently in the scheduler
  50     bool               mbStatic;        ///< Is a static object
  51
  52 protected:
  53     static void StartTimer( sal_uInt64 nMS );
  54
  55     const ImplSchedulerData* GetSchedulerData() const { return mpSchedulerData; }
  56
  57     virtual void SetDeletionFlags();
  58
  59     /**
  60      * How long (in MS) until the Task is ready to be dispatched?
  61      *
  62      * Simply return Scheduler::ImmediateTimeoutMs if you're ready, like an
  63      * Idle. If you have to return Scheduler::InfiniteTimeoutMs, you probably
  64      * need another mechanism to wake up the Scheduler or rely on other
  65      * Tasks to be scheduled, or simply use a polling Timer.
  66      *
  67      * @param nTimeNow the current time
  68      * @return the sleep time of the Task to become ready
  69      */
  70     virtual sal_uInt64 UpdateMinPeriod( sal_uInt64 nTimeNow ) const = 0;
  71
  72 public:
  73     Task( const sal_Char *pDebugName );
  74     Task( const Task& rTask );
  75     virtual ~Task() COVERITY_NOEXCEPT_FALSE;
  76     Task& operator=( const Task& rTask );
  77
  78     void            SetPriority(TaskPriority ePriority);
  79     TaskPriority    GetPriority() const { return mePriority; }
  80
  81     void            SetDebugName( const sal_Char *pDebugName ) { mpDebugName = pDebugName; }
  82     const char     *GetDebugName() const { return mpDebugName; }
  83
  84     // Call handler
  85     virtual void    Invoke() = 0;
  86
  87     virtual void    Start();
  88     void            Stop();
  89
  90     bool            IsActive() const { return mbActive; }
  91
  92     /**
  93      * This function must be called for static tasks, so the Task destructor
  94      * ignores the SchedulerMutex, as it may not be available anymore.
  95      * The cleanup is still correct, as it has already happened in
  96      * DeInitScheduler call well before the static destructor calls.
  97      */
  98     void            SetStatic() { mbStatic = true; }
  99     bool            IsStatic() const { return mbStatic; }
 100 };
 101
 102 #endif // INCLUDED_VCL_TASK_HXX
 103
 104 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */