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100 lines
3.7 KiB
C++
100 lines
3.7 KiB
C++
/*
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* Copyright (C) 2013 Google Inc. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are
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* met:
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*
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* * Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* * Redistributions in binary form must reproduce the above
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* copyright notice, this list of conditions and the following disclaimer
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* in the documentation and/or other materials provided with the
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* distribution.
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* * Neither the name of Google Inc. nor the names of its
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* contributors may be used to endorse or promote products derived from
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* this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#ifndef SKY_ENGINE_PLATFORM_FONTS_FONTDATACACHE_H_
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#define SKY_ENGINE_PLATFORM_FONTS_FONTDATACACHE_H_
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#include "sky/engine/platform/fonts/FontCache.h"
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#include "sky/engine/platform/fonts/FontPlatformData.h"
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#include "sky/engine/wtf/HashMap.h"
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#include "sky/engine/wtf/ListHashSet.h"
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namespace blink {
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class SimpleFontData;
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struct FontDataCacheKeyHash {
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static unsigned hash(const FontPlatformData& platformData)
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{
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return platformData.hash();
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}
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static bool equal(const FontPlatformData& a, const FontPlatformData& b)
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{
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return a == b;
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}
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static const bool safeToCompareToEmptyOrDeleted = true;
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};
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struct FontDataCacheKeyTraits : WTF::GenericHashTraits<FontPlatformData> {
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static const bool emptyValueIsZero = true;
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static const bool needsDestruction = true;
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static const FontPlatformData& emptyValue()
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{
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DEFINE_STATIC_LOCAL(FontPlatformData, key, (0.f, false, false));
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return key;
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}
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static void constructDeletedValue(FontPlatformData& slot, bool)
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{
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new (NotNull, &slot) FontPlatformData(WTF::HashTableDeletedValue);
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}
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static bool isDeletedValue(const FontPlatformData& value)
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{
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return value.isHashTableDeletedValue();
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}
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};
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class FontDataCache {
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public:
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PassRefPtr<SimpleFontData> get(const FontPlatformData*, ShouldRetain = Retain);
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bool contains(const FontPlatformData*) const;
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void release(const SimpleFontData*);
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// This is used by FontVerticalDataCache to mark all items with vertical data
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// that are currently in cache as "in cache", which is later used to sweep the FontVerticalDataCache.
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void markAllVerticalData();
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// Purges items in FontDataCache according to provided severity.
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// Returns true if any removal of cache items actually occurred.
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bool purge(PurgeSeverity);
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private:
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bool purgeLeastRecentlyUsed(int count);
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typedef HashMap<FontPlatformData, pair<RefPtr<SimpleFontData>, unsigned>, FontDataCacheKeyHash, FontDataCacheKeyTraits> Cache;
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Cache m_cache;
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ListHashSet<RefPtr<SimpleFontData> > m_inactiveFontData;
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};
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} // namespace blink
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#endif // SKY_ENGINE_PLATFORM_FONTS_FONTDATACACHE_H_
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