include/vcl/scheduler.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  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_SCHEDULER_HXX
  21 #define INCLUDED_VCL_SCHEDULER_HXX
  22
  23 #include <vcl/dllapi.h>
  24
  25 struct ImplSchedulerContext;
  26
  27 class VCL_DLLPUBLIC Scheduler final
  28 {
  29     friend class SchedulerGuard;
  30     friend class Task;
  31     Scheduler() = delete;
  32
  33     static inline void UpdateSystemTimer( ImplSchedulerContext &rSchedCtx,
  34                                           sal_uInt64 nMinPeriod,
  35                                           bool bForce, sal_uInt64 nTime );
  36
  37     static void ImplStartTimer ( sal_uInt64 nMS, bool bForce, sal_uInt64 nTime );
  38
  39     static void Lock();
  40     static void Unlock();
  41
  42 public:
  43     static constexpr sal_uInt64 ImmediateTimeoutMs = 0;
  44     static constexpr sal_uInt64 InfiniteTimeoutMs  = SAL_MAX_UINT64;
  45
  46     static void       ImplDeInitScheduler();
  47
  48     /**
  49      * System timer callback function, which processes one LO task
  50      *
  51      * Will restart the system timer, so it will process further tasks at the right time.
  52      **/
  53     static void CallbackTaskScheduling();
  54
  55     /**
  56      * Process all events until none is pending
  57      *
  58      * This can busy-lock, if some task or system event always generates new
  59      * events when being processed. Most time it's called in unit tests to
  60      * process all pending events. Internally it just calls
  61      * Application::Reschedule( true ) until it fails.
  62      *
  63      * @see Application::Reschedule
  64      */
  65     static void       ProcessEventsToIdle();
  66
  67     /**
  68      * Wakes up the scheduler
  69      *
  70      * This doesn't handle any events! It just ensures the Scheduler is run as
  71      * soon as possible by forcing the Scheduler timer to fire.
  72      *
  73      * Can be used for complex UpdateMinPeriod function, where the task is
  74      * actually active but not ready and we want to skip the Task::Start()
  75      * queue append for faster reaction.
  76      */
  77     static void       Wakeup();
  78
  79     /// Control the deterministic mode.  In this mode, two subsequent runs of
  80     /// LibreOffice fire about the same amount idles.
  81     static void       SetDeterministicMode(bool bDeterministic);
  82     /// Return the current state of deterministic mode.
  83     static bool       GetDeterministicMode();
  84
  85     // Makes sure that idles are not processed, until the guard is destroyed
  86     struct VCL_DLLPUBLIC IdlesLockGuard final
  87     {
  88         IdlesLockGuard();
  89         ~IdlesLockGuard();
  90     };
  91 };
  92
  93 #endif // INCLUDED_VCL_SCHEDULER_HXX
  94
  95 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */