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 "platform/audio/HRTFDatabaseLoader.h"
34
35#include "platform/Task.h"
36#include "platform/TaskSynchronizer.h"
37#include "public/platform/Platform.h"
38#include "wtf/MainThread.h"
39
40namespace blink {
41
42typedef HeapHashMap<double, WeakMember<HRTFDatabaseLoader> > LoaderMap;
43
44static LoaderMap& loaderMap()
45{
46    DEFINE_STATIC_LOCAL(Persistent<LoaderMap>, map, (new LoaderMap));
47    return *map;
48}
49
50HRTFDatabaseLoader* HRTFDatabaseLoader::createAndLoadAsynchronouslyIfNecessary(float sampleRate)
51{
52    ASSERT(isMainThread());
53
54    HRTFDatabaseLoader* loader = loaderMap().get(sampleRate);
55    if (loader) {
56        ASSERT(sampleRate == loader->databaseSampleRate());
57        return loader;
58    }
59
60    loader = new HRTFDatabaseLoader(sampleRate);
61    loaderMap().add(sampleRate, loader);
62    loader->loadAsynchronously();
63    return loader;
64}
65
66HRTFDatabaseLoader::HRTFDatabaseLoader(float sampleRate)
67    : m_databaseSampleRate(sampleRate)
68{
69    ASSERT(isMainThread());
70}
71
72HRTFDatabaseLoader::~HRTFDatabaseLoader()
73{
74    ASSERT(isMainThread());
75    ASSERT(!m_thread);
76}
77
78void HRTFDatabaseLoader::loadTask()
79{
80    ASSERT(!isMainThread());
81    m_thread->attachGC();
82
83    {
84        MutexLocker locker(m_lock);
85        if (!m_hrtfDatabase) {
86            // Load the default HRTF database.
87            m_hrtfDatabase = HRTFDatabase::create(m_databaseSampleRate);
88        }
89    }
90
91    m_thread->detachGC();
92}
93
94void HRTFDatabaseLoader::loadAsynchronously()
95{
96    ASSERT(isMainThread());
97
98    MutexLocker locker(m_lock);
99    if (!m_hrtfDatabase && !m_thread) {
100        // Start the asynchronous database loading process.
101        m_thread = WebThreadSupportingGC::create("HRTF database loader");
102        m_thread->postTask(new Task(WTF::bind(&HRTFDatabaseLoader::loadTask, this)));
103    }
104}
105
106bool HRTFDatabaseLoader::isLoaded()
107{
108    MutexLocker locker(m_lock);
109    return m_hrtfDatabase;
110}
111
112// This cleanup task is needed just to make sure that the loader thread finishes
113// the load task and thus the loader thread doesn't touch m_thread any more.
114void HRTFDatabaseLoader::cleanupTask(TaskSynchronizer* sync)
115{
116    sync->taskCompleted();
117}
118
119void HRTFDatabaseLoader::waitForLoaderThreadCompletion()
120{
121    if (!m_thread)
122        return;
123
124    TaskSynchronizer sync;
125    m_thread->postTask(new Task(WTF::bind(&HRTFDatabaseLoader::cleanupTask, this, &sync)));
126    sync.waitForTaskCompletion();
127    m_thread.clear();
128}
129
130} // namespace blink
131
132#endif // ENABLE(WEB_AUDIO)
133