1 /* 2 * Copyright (C) 2010 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of 14 * its contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY 18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY 21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #ifndef HRTFDatabaseLoader_h 30 #define HRTFDatabaseLoader_h 31 32 #include "HRTFDatabase.h" 33 #include <wtf/PassRefPtr.h> 34 #include <wtf/RefCounted.h> 35 #include <wtf/RefPtr.h> 36 #include <wtf/Threading.h> 37 38 namespace WebCore { 39 40 // HRTFDatabaseLoader will asynchronously load the default HRTFDatabase in a new thread. 41 42 class HRTFDatabaseLoader : public RefCounted<HRTFDatabaseLoader> { 43 public: 44 // Lazily creates the singleton HRTFDatabaseLoader (if not already created) and starts loading asynchronously (when created the first time). 45 // Returns the singleton HRTFDatabaseLoader. 46 // Must be called from the main thread. 47 static PassRefPtr<HRTFDatabaseLoader> createAndLoadAsynchronouslyIfNecessary(double sampleRate); 48 49 // Returns the singleton HRTFDatabaseLoader. 50 static HRTFDatabaseLoader* loader() { return s_loader; } 51 52 // Both constructor and destructor must be called from the main thread. 53 ~HRTFDatabaseLoader(); 54 55 // Returns true once the default database has been completely loaded. 56 bool isLoaded() const; 57 58 // May not be called on the main thread. 59 // This is so a different background thread may synchronize with the loader thread. 60 void waitForLoaderThreadCompletion(); 61 62 HRTFDatabase* database() { return m_hrtfDatabase.get(); } 63 64 // Called in asynchronous loading thread. 65 void load(); 66 67 // defaultHRTFDatabase() gives access to the loaded database. 68 // This can be called from any thread, but it is the callers responsibilty to call this while the context (and thus HRTFDatabaseLoader) 69 // is still alive. Otherwise this will return 0. 70 static HRTFDatabase* defaultHRTFDatabase(); 71 72 private: 73 // Both constructor and destructor must be called from the main thread. 74 explicit HRTFDatabaseLoader(double sampleRate); 75 76 // If it hasn't already been loaded, creates a new thread and initiates asynchronous loading of the default database. 77 // This must be called from the main thread. 78 void loadAsynchronously(); 79 80 double databaseSampleRate() const { return m_databaseSampleRate; } 81 82 static HRTFDatabaseLoader* s_loader; // singleton 83 OwnPtr<HRTFDatabase> m_hrtfDatabase; 84 ThreadIdentifier m_databaseLoaderThread; 85 bool m_startedLoadingDatabase; 86 double m_databaseSampleRate; 87 }; 88 89 90 } // namespace WebCore 91 92 #endif // HRTFDatabaseLoader_h 93
