 28e2075280
			
		
	
	28e2075280
	
	
	
		
			
			trunk/talk git-svn-id: http://webrtc.googlecode.com/svn/trunk@4318 4adac7df-926f-26a2-2b94-8c16560cd09d
		
			
				
	
	
		
			106 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			106 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| /*
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|  * libjingle
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|  * Copyright 2004--2010, Google Inc.
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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 met:
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|  *
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|  *  1. Redistributions of source code must retain the above copyright notice, 
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|  *     this list of conditions and the following disclaimer.
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|  *  2. Redistributions in binary form must reproduce the above copyright notice,
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|  *     this list of conditions and the following disclaimer in the documentation
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|  *     and/or other materials provided with the distribution.
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|  *  3. The name of the author may not be used to endorse or promote products 
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|  *     derived from this software without specific prior written permission.
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|  *
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|  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
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|  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
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|  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
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|  * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
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|  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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|  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
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|  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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|  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 
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|  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 
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|  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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|  */
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| 
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| #ifndef TALK_SOUND_AUTOMATICALLYCHOSENSOUNDSYSTEM_H_
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| #define TALK_SOUND_AUTOMATICALLYCHOSENSOUNDSYSTEM_H_
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| 
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| #include "talk/base/common.h"
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| #include "talk/base/logging.h"
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| #include "talk/base/scoped_ptr.h"
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| #include "talk/sound/soundsysteminterface.h"
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| #include "talk/sound/soundsystemproxy.h"
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| 
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| namespace cricket {
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| 
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| // A function type that creates an instance of a sound system implementation.
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| typedef SoundSystemInterface *(*SoundSystemCreator)();
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| 
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| // An AutomaticallyChosenSoundSystem is a sound system proxy that defers to
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| // an instance of the first sound system implementation in a list that
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| // successfully initializes.
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| template <const SoundSystemCreator kSoundSystemCreators[], int kNumSoundSystems>
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| class AutomaticallyChosenSoundSystem : public SoundSystemProxy {
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|  public:
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|   // Chooses and initializes the underlying sound system.
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|   virtual bool Init();
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|   // Terminates the underlying sound system implementation, but caches it for
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|   // future re-use.
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|   virtual void Terminate();
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| 
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|   virtual const char *GetName() const;
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| 
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|  private:
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|   talk_base::scoped_ptr<SoundSystemInterface> sound_systems_[kNumSoundSystems];
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| };
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| 
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| template <const SoundSystemCreator kSoundSystemCreators[], int kNumSoundSystems>
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| bool AutomaticallyChosenSoundSystem<kSoundSystemCreators,
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|                                     kNumSoundSystems>::Init() {
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|   if (wrapped_) {
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|     return true;
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|   }
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|   for (int i = 0; i < kNumSoundSystems; ++i) {
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|     if (!sound_systems_[i].get()) {
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|       sound_systems_[i].reset((*kSoundSystemCreators[i])());
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|     }
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|     if (sound_systems_[i]->Init()) {
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|       // This is the first sound system in the list to successfully
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|       // initialize, so we're done.
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|       wrapped_ = sound_systems_[i].get();
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|       break;
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|     }
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|     // Else it failed to initialize, so try the remaining ones.
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|   }
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|   if (!wrapped_) {
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|     LOG(LS_ERROR) << "Failed to find a usable sound system";
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|     return false;
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|   }
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|   LOG(LS_INFO) << "Selected " << wrapped_->GetName() << " sound system";
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|   return true;
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| }
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| 
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| template <const SoundSystemCreator kSoundSystemCreators[], int kNumSoundSystems>
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| void AutomaticallyChosenSoundSystem<kSoundSystemCreators,
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|                                     kNumSoundSystems>::Terminate() {
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|   if (!wrapped_) {
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|     return;
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|   }
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|   wrapped_->Terminate();
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|   wrapped_ = NULL;
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|   // We do not free the scoped_ptrs because we may be re-init'ed soon.
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| }
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| 
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| template <const SoundSystemCreator kSoundSystemCreators[], int kNumSoundSystems>
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| const char *AutomaticallyChosenSoundSystem<kSoundSystemCreators,
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|                                            kNumSoundSystems>::GetName() const {
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|   return wrapped_ ? wrapped_->GetName() : "automatic";
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| }
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| 
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| }  // namespace cricket
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| 
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| #endif  // TALK_SOUND_AUTOMATICALLYCHOSENSOUNDSYSTEM_H_
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