Support multiple HRTFDatabases for different sample-rates

Source/core/platform/audio/HRTFDatabaseLoader.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 21 matching lines @@
 
 #include "core/platform/audio/HRTFDatabaseLoader.h"
 
 #include "core/platform/PlatformMemoryInstrumentation.h"
 #include "core/platform/audio/HRTFDatabase.h"
 #include <wtf/MainThread.h>
 
 namespace WebCore {
 
 // Singleton
-HRTFDatabaseLoader* HRTFDatabaseLoader::s_loader = 0;
+HRTFDatabaseLoader::LoaderMap* HRTFDatabaseLoader::s_loaderMap = 0;
 
 PassRefPtr<HRTFDatabaseLoader> HRTFDatabaseLoader::createAndLoadAsynchronouslyIfNecessary(float sampleRate)
 {
     ASSERT(isMainThread());
 
     RefPtr<HRTFDatabaseLoader> loader;
     
-    if (!s_loader) {
-        // Lazily create and load.
-        loader = adoptRef(new HRTFDatabaseLoader(sampleRate));
-        s_loader = loader.get();
-        loader->loadAsynchronously();
-    } else {
-        loader = s_loader;
+    if (!s_loaderMap)
+        s_loaderMap = adoptPtr(new LoaderMap()).leakPtr();
+
+    loader = s_loaderMap->get(sampleRate);
+    if (loader.get()) {

[Ken Russell (switch to Gerrit), 2013/05/11 01:35:16]

RefPtr has a conversion operator to bool, so you should be able to write this as
"if (loader)".

[Chris Rogers, 2013/05/13 20:05:22]

Done.

         ASSERT(sampleRate == loader->databaseSampleRate());
+        return loader;
     }
-    
+
+    loader = adoptRef(new HRTFDatabaseLoader(sampleRate));
+    s_loaderMap->add(sampleRate, loader);
+
+    loader->loadAsynchronously();
+
     return loader;
 }
 
 HRTFDatabaseLoader::HRTFDatabaseLoader(float sampleRate)
     : m_databaseLoaderThread(0)
     , m_databaseSampleRate(sampleRate)
 {
     ASSERT(isMainThread());
 }
 
 HRTFDatabaseLoader::~HRTFDatabaseLoader()
 {
     ASSERT(isMainThread());
 
     waitForLoaderThreadCompletion();
     m_hrtfDatabase.clear();
-    
-    // Clear out singleton.
-    ASSERT(this == s_loader);
-    s_loader = 0;
 }
 
-
 // Asynchronously load the database in this thread.
 static void databaseLoaderEntry(void* threadData)
 {
     HRTFDatabaseLoader* loader = reinterpret_cast<HRTFDatabaseLoader*>(threadData);
     ASSERT(loader);
     loader->load();
 }
 
 void HRTFDatabaseLoader::load()
 {
@@ skipping 24 matching lines @@
 void HRTFDatabaseLoader::waitForLoaderThreadCompletion()
 {
     MutexLocker locker(m_threadLock);
     
     // waitForThreadCompletion() should not be called twice for the same thread.
     if (m_databaseLoaderThread)
         waitForThreadCompletion(m_databaseLoaderThread);
     m_databaseLoaderThread = 0;
 }
 
-HRTFDatabase* HRTFDatabaseLoader::defaultHRTFDatabase()
-{
-    if (!s_loader)
-        return 0;
-    
-    return s_loader->database();
-}
-
 void HRTFDatabaseLoader::reportMemoryUsage(MemoryObjectInfo* memoryObjectInfo) const
 {
     MemoryClassInfo info(memoryObjectInfo, this, PlatformMemoryTypes::AudioSharedData);
     info.addMember(m_hrtfDatabase, "hrtfDatabase");
 }
 
+void HRTFDatabaseLoader::LoaderMap::reportMemoryUsage(MemoryObjectInfo* memoryObjectInfo) const
+{
+    if (s_loaderMap) {
+        for (HRTFDatabaseLoader::LoaderMap::iterator i = s_loaderMap->begin(); i != s_loaderMap->end(); ++i) {
+            HRTFDatabaseLoader* loader = i.get()->value.get();
+            loader->reportMemoryUsage(memoryObjectInfo);
+        }
+    }
+}
+
 } // namespace WebCore
 
 #endif // ENABLE(WEB_AUDIO)