include/comphelper/solarmutex.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_COMPHELPER_SOLARMUTEX_HXX
  21 #define INCLUDED_COMPHELPER_SOLARMUTEX_HXX
  22
  23 #include <sal/config.h>
  24
  25 #include <assert.h>
  26 #include <atomic>
  27 #include <thread>
  28
  29 #include <osl/mutex.hxx>
  30 #include <comphelper/comphelperdllapi.h>
  31
  32 namespace comphelper {
  33
  34
  35 /**
  36  * SolarMutex, needed for VCL's Application::GetSolarMutex().
  37  *
  38  * The SolarMutex is the one big recursive code lock used
  39  * to protect the vast majority of the LibreOffice code-base,
  40  * in particular anything that is graphical and the cores of
  41  * the applications.
  42  *
  43  * Treat this as a singleton, as its constructor sets a global
  44  * pointing at itself.
  45  */
  46 class COMPHELPER_DLLPUBLIC SolarMutex {
  47 public:
  48     typedef void (*BeforeReleaseHandler) ();
  49
  50     SolarMutex();
  51     virtual ~SolarMutex();
  52
  53     void SetBeforeReleaseHandler( const BeforeReleaseHandler& rLink )
  54          { m_aBeforeReleaseHandler = rLink; }
  55
  56     void acquire( sal_uInt32 nLockCount = 1 );
  57     sal_uInt32 release( bool bUnlockAll = false );
  58
  59     virtual bool tryToAcquire();
  60
  61     // returns true, if the mutex is owned by the current thread
  62     virtual bool IsCurrentThread() const;
  63
  64     /// Help components to get the SolarMutex easily.
  65     static SolarMutex *get();
  66
  67 protected:
  68     virtual sal_uInt32 doRelease( bool bUnlockAll );
  69     virtual void doAcquire( sal_uInt32 nLockCount );
  70
  71     osl::Mutex            m_aMutex;
  72     sal_uInt32            m_nCount;
  73
  74 private:
  75     std::atomic<std::thread::id> m_nThreadId;
  76
  77     SolarMutex(const SolarMutex&) = delete;
  78     SolarMutex& operator=(const SolarMutex&) = delete;
  79
  80     BeforeReleaseHandler  m_aBeforeReleaseHandler;
  81 };
  82
  83 inline void SolarMutex::acquire( sal_uInt32 nLockCount )
  84 {
  85     assert( nLockCount > 0 );
  86     doAcquire( nLockCount );
  87 }
  88
  89 inline sal_uInt32 SolarMutex::release( bool bUnlockAll )
  90 {
  91      return doRelease( bUnlockAll );
  92 }
  93
  94 }
  95
  96 #endif // INCLUDED_COMPHELPER_SOLARMUTEX_HXX
  97
  98 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */