111 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			111 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| ///////////////////////////////////////////////////////////////////////////
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| //
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| // Copyright (c) 2005, Industrial Light & Magic, a division of Lucas
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| // Digital Ltd. LLC
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| //
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| // All rights reserved.
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| //
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| // Redistribution and use in source and binary forms, with or without
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| // modification, are permitted provided that the following conditions are
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| // met:
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| // *       Redistributions of source code must retain the above copyright
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| // notice, this list of conditions and the following disclaimer.
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| // *       Redistributions in binary form must reproduce the above
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| // copyright notice, this list of conditions and the following disclaimer
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| // in the documentation and/or other materials provided with the
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| // distribution.
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| // *       Neither the name of Industrial Light & Magic nor the names of
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| // its contributors may be used to endorse or promote products derived
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| // from this software without specific prior written permission.
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| //
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| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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| //
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| ///////////////////////////////////////////////////////////////////////////
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| 
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| #ifndef INCLUDED_ILM_THREAD_SEMAPHORE_H
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| #define INCLUDED_ILM_THREAD_SEMAPHORE_H
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| 
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| //-----------------------------------------------------------------------------
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| //
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| //	class Semaphore -- a wrapper class for
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| //	system-dependent counting semaphores
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| //
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| //-----------------------------------------------------------------------------
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| 
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| #include "IlmBaseConfig.h"
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| 
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| #if defined _WIN32 || defined _WIN64
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|     #ifdef NOMINMAX
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|         #undef NOMINMAX
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|     #endif
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|     #define NOMINMAX
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|     #include <windows.h>
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| #elif HAVE_PTHREAD && !HAVE_POSIX_SEMAPHORES
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|     #include <pthread.h>
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| #elif HAVE_PTHREAD && HAVE_POSIX_SEMAPHORES
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|     #include <semaphore.h>
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| #endif
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| 
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| namespace IlmThread {
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| 
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| 
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| class Semaphore
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| {
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|   public:
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| 
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|     Semaphore (unsigned int value = 0);
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|     virtual ~Semaphore();
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| 
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|     void	wait();
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|     bool	tryWait();
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|     void	post();
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|     int		value() const;
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| 
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|   private:
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| 
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|     #if defined _WIN32 || defined _WIN64
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| 
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|     mutable HANDLE _semaphore;
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| 
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|     #elif HAVE_PTHREAD && !HAVE_POSIX_SEMAPHORES
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| 
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|     //
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|     // If the platform has Posix threads but no semapohores,
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|     // then we implement them ourselves using condition variables
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|     //
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| 
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|     struct sema_t
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|     {
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|         unsigned int count;
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|         unsigned long numWaiting;
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|         pthread_mutex_t mutex;
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|         pthread_cond_t nonZero;
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|     };
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| 
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|     mutable sema_t _semaphore;
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| 
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|     #elif HAVE_PTHREAD && HAVE_POSIX_SEMAPHORES
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| 
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|     mutable sem_t _semaphore;
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| 
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|     #endif
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| 
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|     void operator = (const Semaphore& s);	// not implemented
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|     Semaphore (const Semaphore& s);		// not implemented
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| };
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| 
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| 
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| } // namespace IlmThread
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| 
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| #endif
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