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28 #ifndef TALK_SOUND_AUTOMATICALLYCHOSENSOUNDSYSTEM_H_
29 #define TALK_SOUND_AUTOMATICALLYCHOSENSOUNDSYSTEM_H_
31 #include "talk/base/common.h"
32 #include "talk/base/logging.h"
33 #include "talk/base/scoped_ptr.h"
34 #include "talk/sound/soundsysteminterface.h"
35 #include "talk/sound/soundsystemproxy.h"
39 // A function type that creates an instance of a sound system implementation.
40 typedef SoundSystemInterface *(*SoundSystemCreator)();
42 // An AutomaticallyChosenSoundSystem is a sound system proxy that defers to
43 // an instance of the first sound system implementation in a list that
44 // successfully initializes.
45 template <const SoundSystemCreator kSoundSystemCreators[], int kNumSoundSystems>
46 class AutomaticallyChosenSoundSystem : public SoundSystemProxy {
48 // Chooses and initializes the underlying sound system.
50 // Terminates the underlying sound system implementation, but caches it for
52 virtual void Terminate();
54 virtual const char *GetName() const;
57 talk_base::scoped_ptr<SoundSystemInterface> sound_systems_[kNumSoundSystems];
60 template <const SoundSystemCreator kSoundSystemCreators[], int kNumSoundSystems>
61 bool AutomaticallyChosenSoundSystem<kSoundSystemCreators,
62 kNumSoundSystems>::Init() {
66 for (int i = 0; i < kNumSoundSystems; ++i) {
67 if (!sound_systems_[i].get()) {
68 sound_systems_[i].reset((*kSoundSystemCreators[i])());
70 if (sound_systems_[i]->Init()) {
71 // This is the first sound system in the list to successfully
72 // initialize, so we're done.
73 wrapped_ = sound_systems_[i].get();
76 // Else it failed to initialize, so try the remaining ones.
79 LOG(LS_ERROR) << "Failed to find a usable sound system";
82 LOG(LS_INFO) << "Selected " << wrapped_->GetName() << " sound system";
86 template <const SoundSystemCreator kSoundSystemCreators[], int kNumSoundSystems>
87 void AutomaticallyChosenSoundSystem<kSoundSystemCreators,
88 kNumSoundSystems>::Terminate() {
92 wrapped_->Terminate();
94 // We do not free the scoped_ptrs because we may be re-init'ed soon.
97 template <const SoundSystemCreator kSoundSystemCreators[], int kNumSoundSystems>
98 const char *AutomaticallyChosenSoundSystem<kSoundSystemCreators,
99 kNumSoundSystems>::GetName() const {
100 return wrapped_ ? wrapped_->GetName() : "automatic";
103 } // namespace cricket
105 #endif // TALK_SOUND_AUTOMATICALLYCHOSENSOUNDSYSTEM_H_