1/*
2 * Copyright (C) 2014 Apple 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 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
23 * THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "ViewSnapshotStore.h"
28
29#include "WebBackForwardList.h"
30#include "WebPageProxy.h"
31#include <wtf/NeverDestroyed.h>
32
33#if PLATFORM(IOS_FAMILY)
34static const size_t maximumSnapshotCacheSize = 50 * (1024 * 1024);
35#else
36static const size_t maximumSnapshotCacheSize = 400 * (1024 * 1024);
37#endif
38
39namespace WebKit {
40using namespace WebCore;
41
42ViewSnapshotStore::ViewSnapshotStore()
43{
44}
45
46ViewSnapshotStore::~ViewSnapshotStore()
47{
48 discardSnapshotImages();
49}
50
51ViewSnapshotStore& ViewSnapshotStore::singleton()
52{
53 static NeverDestroyed<ViewSnapshotStore> store;
54 return store;
55}
56
57void ViewSnapshotStore::didAddImageToSnapshot(ViewSnapshot& snapshot)
58{
59 bool isNewEntry = m_snapshotsWithImages.add(&snapshot).isNewEntry;
60 ASSERT_UNUSED(isNewEntry, isNewEntry);
61 m_snapshotCacheSize += snapshot.imageSizeInBytes();
62}
63
64void ViewSnapshotStore::willRemoveImageFromSnapshot(ViewSnapshot& snapshot)
65{
66 bool removed = m_snapshotsWithImages.remove(&snapshot);
67 ASSERT_UNUSED(removed, removed);
68 m_snapshotCacheSize -= snapshot.imageSizeInBytes();
69}
70
71void ViewSnapshotStore::pruneSnapshots(WebPageProxy& webPageProxy)
72{
73 if (m_snapshotCacheSize <= maximumSnapshotCacheSize)
74 return;
75
76 ASSERT(!m_snapshotsWithImages.isEmpty());
77
78 // FIXME: We have enough information to do smarter-than-LRU eviction (making use of the back-forward lists, etc.)
79
80 m_snapshotsWithImages.first()->clearImage();
81}
82
83void ViewSnapshotStore::recordSnapshot(WebPageProxy& webPageProxy, WebBackForwardListItem& item)
84{
85 if (webPageProxy.isShowingNavigationGestureSnapshot())
86 return;
87
88 pruneSnapshots(webPageProxy);
89
90 webPageProxy.willRecordNavigationSnapshot(item);
91
92 auto snapshot = webPageProxy.takeViewSnapshot();
93 if (!snapshot)
94 return;
95
96 snapshot->setRenderTreeSize(webPageProxy.renderTreeSize());
97 snapshot->setDeviceScaleFactor(webPageProxy.deviceScaleFactor());
98 snapshot->setBackgroundColor(webPageProxy.pageExtendedBackgroundColor());
99 snapshot->setViewScrollPosition(WebCore::roundedIntPoint(webPageProxy.viewScrollPosition()));
100
101 item.setSnapshot(WTFMove(snapshot));
102}
103
104void ViewSnapshotStore::discardSnapshotImages()
105{
106 while (!m_snapshotsWithImages.isEmpty())
107 m_snapshotsWithImages.first()->clearImage();
108}
109
110ViewSnapshot::~ViewSnapshot()
111{
112 clearImage();
113}
114
115} // namespace WebKit
116