1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95
|
/*
* Copyright (C) 2007, 2015 Apple 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
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include "HistoryItem.h"
#include <wtf/Forward.h>
#include <wtf/ListHashSet.h>
#include <wtf/Noncopyable.h>
namespace WebCore {
class CachedPage;
class LocalFrame;
class Page;
enum class PruningReason { None, ProcessSuspended, MemoryPressure, ReachedMaxSize };
class BackForwardCache {
WTF_MAKE_NONCOPYABLE(BackForwardCache);
WTF_MAKE_FAST_ALLOCATED;
public:
// Function to obtain the global back/forward cache.
WEBCORE_EXPORT static BackForwardCache& singleton();
bool canCache(Page&) const;
// Used when memory is low to prune some cached pages.
WEBCORE_EXPORT void pruneToSizeNow(unsigned maxSize, PruningReason);
WEBCORE_EXPORT void setMaxSize(unsigned); // number of pages to cache.
unsigned maxSize() const { return m_maxSize; }
WEBCORE_EXPORT std::unique_ptr<CachedPage> suspendPage(Page&);
WEBCORE_EXPORT bool addIfCacheable(HistoryItem&, Page*); // Prunes if maxSize() is exceeded.
WEBCORE_EXPORT void remove(HistoryItem&);
CachedPage* get(HistoryItem&, Page*);
std::unique_ptr<CachedPage> take(HistoryItem&, Page*);
void removeAllItemsForPage(Page&);
WEBCORE_EXPORT void clearEntriesForOrigins(const HashSet<RefPtr<SecurityOrigin>>&);
unsigned pageCount() const { return m_items.size(); }
WEBCORE_EXPORT unsigned frameCount() const;
void markPagesForDeviceOrPageScaleChanged(Page&);
void markPagesForContentsSizeChanged(Page&);
#if ENABLE(VIDEO)
void markPagesForCaptionPreferencesChanged();
#endif
private:
BackForwardCache();
~BackForwardCache() = delete; // Make sure nobody accidentally calls delete -- WebCore does not delete singletons.
static bool canCachePageContainingThisFrame(LocalFrame&);
enum class ForceSuspension : bool { No, Yes };
std::unique_ptr<CachedPage> trySuspendPage(Page&, ForceSuspension);
void prune(PruningReason);
void dump() const;
ListHashSet<RefPtr<HistoryItem>> m_items;
unsigned m_maxSize {0};
#if ASSERT_ENABLED
bool m_isInRemoveAllItemsForPage { false };
#endif
friend class WTF::NeverDestroyed<BackForwardCache>;
};
} // namespace WebCore
|