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31 #ifndef FontDataCache_h
32 #define FontDataCache_h
34 #include "platform/fonts/FontCache.h"
35 #include "platform/fonts/FontPlatformData.h"
36 #include "wtf/HashMap.h"
37 #include "wtf/ListHashSet.h"
43 struct FontDataCacheKeyHash {
44 static unsigned hash(const FontPlatformData& platformData)
46 return platformData.hash();
49 static bool equal(const FontPlatformData& a, const FontPlatformData& b)
54 static const bool safeToCompareToEmptyOrDeleted = true;
57 struct FontDataCacheKeyTraits : WTF::GenericHashTraits<FontPlatformData> {
58 static const bool emptyValueIsZero = true;
59 static const bool needsDestruction = true;
60 static const FontPlatformData& emptyValue()
62 DEFINE_STATIC_LOCAL(FontPlatformData, key, (0.f, false, false));
65 static void constructDeletedValue(FontPlatformData& slot, bool)
67 new (NotNull, &slot) FontPlatformData(WTF::HashTableDeletedValue);
69 static bool isDeletedValue(const FontPlatformData& value)
71 return value.isHashTableDeletedValue();
77 PassRefPtr<SimpleFontData> get(const FontPlatformData*, ShouldRetain = Retain);
78 bool contains(const FontPlatformData*) const;
79 void release(const SimpleFontData*);
81 // This is used by FontVerticalDataCache to mark all items with vertical data
82 // that are currently in cache as "in cache", which is later used to sweep the FontVerticalDataCache.
83 void markAllVerticalData();
85 // Purges items in FontDataCache according to provided severity.
86 // Returns true if any removal of cache items actually occurred.
87 bool purge(PurgeSeverity);
90 bool purgeLeastRecentlyUsed(int count);
92 typedef HashMap<FontPlatformData, pair<RefPtr<SimpleFontData>, unsigned>, FontDataCacheKeyHash, FontDataCacheKeyTraits> Cache;
94 ListHashSet<RefPtr<SimpleFontData> > m_inactiveFontData;