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#include "config.h"
30
31#if ENABLE(WEB_AUDIO)
32
33#include "HRTFDatabaseLoader.h"
34
35#include "HRTFDatabase.h"
36
37namespace WebCore {
38
39// Singleton
40HRTFDatabaseLoader* HRTFDatabaseLoader::s_loader = 0;
41
42PassRefPtr<HRTFDatabaseLoader> HRTFDatabaseLoader::createAndLoadAsynchronouslyIfNecessary(double sampleRate)
43{
44    ASSERT(isMainThread());
45
46    RefPtr<HRTFDatabaseLoader> loader;
47
48    if (!s_loader) {
49        // Lazily create and load.
50        loader = adoptRef(new HRTFDatabaseLoader(sampleRate));
51        s_loader = loader.get();
52        loader->loadAsynchronously();
53    } else {
54        loader = s_loader;
55        ASSERT(sampleRate == loader->databaseSampleRate());
56    }
57
58    return loader;
59}
60
61HRTFDatabaseLoader::HRTFDatabaseLoader(double sampleRate)
62    : m_hrtfDatabase(0)
63    , m_databaseLoaderThread(0)
64    , m_startedLoadingDatabase(false)
65    , m_databaseSampleRate(sampleRate)
66{
67    ASSERT(isMainThread());
68}
69
70HRTFDatabaseLoader::~HRTFDatabaseLoader()
71{
72    ASSERT(isMainThread());
73
74    if (m_startedLoadingDatabase)
75        waitForThreadCompletion(m_databaseLoaderThread, 0);
76
77    m_startedLoadingDatabase = false;
78    m_databaseLoaderThread = 0;
79
80    m_hrtfDatabase.clear();
81
82    // Clear out singleton.
83    ASSERT(this == s_loader);
84    s_loader = 0;
85}
86
87
88// Asynchronously load the database in this thread.
89static void* databaseLoaderEntry(void* threadData)
90{
91    HRTFDatabaseLoader* loader = reinterpret_cast<HRTFDatabaseLoader*>(threadData);
92    ASSERT(loader);
93    loader->load();
94
95    return 0;
96}
97
98void HRTFDatabaseLoader::load()
99{
100    ASSERT(!isMainThread());
101    if (!m_hrtfDatabase.get()) {
102        // Load the default HRTF database.
103        m_hrtfDatabase = HRTFDatabase::create(m_databaseSampleRate);
104    }
105}
106
107void HRTFDatabaseLoader::loadAsynchronously()
108{
109    ASSERT(isMainThread());
110
111    if (!m_hrtfDatabase.get() && !m_startedLoadingDatabase) {
112        // Start the asynchronous database loading process.
113        m_startedLoadingDatabase = true;
114        m_databaseLoaderThread = createThread(databaseLoaderEntry, this, "HRTF database loader");
115    }
116}
117
118bool HRTFDatabaseLoader::isLoaded() const
119{
120    return m_hrtfDatabase.get();
121}
122
123
124void HRTFDatabaseLoader::waitForLoaderThreadCompletion()
125{
126    ASSERT(!isMainThread());
127    ASSERT(m_databaseLoaderThread);
128    waitForThreadCompletion(m_databaseLoaderThread, 0);
129}
130
131HRTFDatabase* HRTFDatabaseLoader::defaultHRTFDatabase()
132{
133    if (!s_loader)
134        return 0;
135
136    return s_loader->database();
137}
138
139} // namespace WebCore
140
141#endif // ENABLE(WEB_AUDIO)
142