dep/include/zthread/PrioritySemaphore.h

   1 /*
   2  * Copyright (c) 2005, Eric Crahen
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a copy
   5  * of this software and associated documentation files (the "Software"), to deal
   6  * in the Software without restriction, including without limitation the rights
   7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   8  * copies of the Software, and to permit persons to whom the Software is furnished
   9  * to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in all
  12  * copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  17  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  18  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  19  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  20  *
  21  */
  22
  23
  24 #ifndef __ZTPRIORITYSEMAPHORE_H__
  25 #define __ZTPRIORITYSEMAPHORE_H__
  26
  27 #include "zthread/Lockable.h"
  28 #include "zthread/NonCopyable.h"
  29
  30 namespace ZThread {
  31
  32   class PrioritySemaphoreImpl;
  33
  34   /**
  35    * @class PrioritySemaphore
  36    * @author Eric Crahen <http://www.code-foo.com>
  37    * @date <2003-07-16T15:36:07-0400>
  38    * @version 2.2.1
  39    *
  40    * A PrioritySemaphore operates in the same way as a Semaphore. Its an owner-less
  41    * Lockable object that is sensitive to priority.
  42    *
  43    * <b>Scheduling</b>
  44    *
  45    * Threads blocked on a PrioritySemaphore are resumed in priority order, highest
  46    * priority first.
  47    *
  48    * <b>Error Checking</b>
  49    *
  50    * An attempt to increase a PrioritySemaphore beyond its maximum value will result in
  51    * an InvalidOp_Exception.
  52    *
  53    * @see Semaphore
  54    */
  55   class ZTHREAD_API PrioritySemaphore : public Lockable, private NonCopyable {
  56
  57     PrioritySemaphoreImpl* _impl;
  58
  59   public:
  60
  61     /**
  62      * @see Semaphore::Semaphore(int count, unsigned int maxCount)
  63      */
  64     PrioritySemaphore(int count = 1, unsigned int maxCount = 1);
  65
  66     /**
  67      * @see Semaphore::~Semaphore()
  68      */
  69     virtual ~PrioritySemaphore();
  70
  71     /**
  72      * @see Semaphore::wait()
  73      */
  74     void wait();
  75
  76     /**
  77      * @see Semaphore::tryWait(unsigned long)
  78      */
  79     bool tryWait(unsigned long);
  80
  81     /**
  82      * @see Semaphore::post()
  83      */
  84     void post();
  85
  86     /**
  87      * @see Semaphore::count()
  88      */
  89     virtual int count();
  90
  91     /**
  92      * @see Semaphore::tryAcquire(unsigned long timeout)
  93      */
  94     virtual bool tryAcquire(unsigned long timeout);
  95
  96     /**
  97      * @see Semaphore::acquire()
  98      */
  99     virtual void acquire();
 100
 101     /**
 102      * @see Semaphore::release()
 103      */
 104     virtual void release();
 105
 106   };
 107
 108
 109 } // namespace ZThread
 110
 111 #endif // __ZTPRIORITYSEMAPHORE_H__