juce/source/src/threads/juce_ScopedWriteLock.h

   1 /*
   2   ==============================================================================
   3
   4    This file is part of the JUCE library - "Jules' Utility Class Extensions"
   5    Copyright 2004-11 by Raw Material Software Ltd.
   6
   7   ------------------------------------------------------------------------------
   8
   9    JUCE can be redistributed and/or modified under the terms of the GNU General
  10    Public License (Version 2), as published by the Free Software Foundation.
  11    A copy of the license is included in the JUCE distribution, or can be found
  12    online at www.gnu.org/licenses.
  13
  14    JUCE is distributed in the hope that it will be useful, but WITHOUT ANY
  15    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  16    A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
  17
  18   ------------------------------------------------------------------------------
  19
  20    To release a closed-source product which uses JUCE, commercial licenses are
  21    available: visit www.rawmaterialsoftware.com/juce for more information.
  22
  23   ==============================================================================
  24 */
  25
  26 #ifndef __JUCE_SCOPEDWRITELOCK_JUCEHEADER__
  27 #define __JUCE_SCOPEDWRITELOCK_JUCEHEADER__
  28
  29 #include "juce_ReadWriteLock.h"
  30
  31
  32 //==============================================================================
  33 /**
  34     Automatically locks and unlocks a ReadWriteLock object.
  35
  36     Use one of these as a local variable to control access to a ReadWriteLock.
  37
  38     e.g. @code
  39
  40     ReadWriteLock myLock;
  41
  42     for (;;)
  43     {
  44         const ScopedWriteLock myScopedLock (myLock);
  45         // myLock is now locked
  46
  47         ...do some stuff...
  48
  49         // myLock gets unlocked here.
  50     }
  51     @endcode
  52
  53     @see ReadWriteLock, ScopedReadLock
  54 */
  55 class JUCE_API  ScopedWriteLock
  56 {
  57 public:
  58     //==============================================================================
  59     /** Creates a ScopedWriteLock.
  60
  61         As soon as it is created, this will call ReadWriteLock::enterWrite(), and
  62         when the ScopedWriteLock object is deleted, the ReadWriteLock will
  63         be unlocked.
  64
  65         Make sure this object is created and deleted by the same thread,
  66         otherwise there are no guarantees what will happen! Best just to use it
  67         as a local stack object, rather than creating one with the new() operator.
  68     */
  69     inline explicit ScopedWriteLock (const ReadWriteLock& lock) noexcept : lock_ (lock) { lock.enterWrite(); }
  70
  71     /** Destructor.
  72
  73         The ReadWriteLock's exitWrite() method will be called when the destructor is called.
  74
  75         Make sure this object is created and deleted by the same thread,
  76         otherwise there are no guarantees what will happen!
  77     */
  78     inline ~ScopedWriteLock() noexcept                                   { lock_.exitWrite(); }
  79
  80
  81 private:
  82     //==============================================================================
  83     const ReadWriteLock& lock_;
  84
  85     JUCE_DECLARE_NON_COPYABLE (ScopedWriteLock);
  86 };
  87
  88
  89 #endif   // __JUCE_SCOPEDWRITELOCK_JUCEHEADER__