/*
* Copyright (C) 2013 Google Inc. All rights reserved.
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* modification, are permitted provided that the following conditions are
* met:
*
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* 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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*
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*/
#ifndef FontDataCache_h
#define FontDataCache_h
#include "platform/fonts/FontCache.h"
#include "platform/fonts/FontPlatformData.h"
#include "wtf/HashMap.h"
#include "wtf/ListHashSet.h"
namespace WebCore {
class SimpleFontData;
struct FontDataCacheKeyHash {
static unsigned hash(const FontPlatformData& platformData)
{
return platformData.hash();
}
static bool equal(const FontPlatformData& a, const FontPlatformData& b)
{
return a == b;
}
static const bool safeToCompareToEmptyOrDeleted = true;
};
struct FontDataCacheKeyTraits : WTF::GenericHashTraits<FontPlatformData> {
static const bool emptyValueIsZero = true;
static const bool needsDestruction = true;
static const FontPlatformData& emptyValue()
{
DEFINE_STATIC_LOCAL(FontPlatformData, key, (0.f, false, false));
return key;
}
static void constructDeletedValue(FontPlatformData& slot)
{
new (NotNull, &slot) FontPlatformData(WTF::HashTableDeletedValue);
}
static bool isDeletedValue(const FontPlatformData& value)
{
return value.isHashTableDeletedValue();
}
};
class FontDataCache {
public:
PassRefPtr<SimpleFontData> get(const FontPlatformData*, ShouldRetain = Retain);
bool contains(const FontPlatformData*) const;
void release(const SimpleFontData*);
// This is used by FontVerticalDataCache to mark all items with vertical data
// that are currently in cache as "in cache", which is later used to sweep the FontVerticalDataCache.
void markAllVerticalData();
// Purges items in FontDataCache according to provided severity.
// Returns true if any removal of cache items actually occurred.
bool purge(PurgeSeverity);
private:
bool purgeLeastRecentlyUsed(int count);
typedef HashMap<FontPlatformData, pair<RefPtr<SimpleFontData>, unsigned>, FontDataCacheKeyHash, FontDataCacheKeyTraits> Cache;
Cache m_cache;
ListHashSet<RefPtr<SimpleFontData> > m_inactiveFontData;
};
}
#endif