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diff --git a/skia/sgl/SkGlyphCache.h b/skia/sgl/SkGlyphCache.h
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+/* libs/graphics/sgl/SkGlyphCache.h
+**
+** Copyright 2006, Google Inc.
+**
+** Licensed under the Apache License, Version 2.0 (the "License"); 
+** you may not use this file except in compliance with the License. 
+** You may obtain a copy of the License at 
+**
+**     http://www.apache.org/licenses/LICENSE-2.0 
+**
+** Unless required by applicable law or agreed to in writing, software 
+** distributed under the License is distributed on an "AS IS" BASIS, 
+** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
+** See the License for the specific language governing permissions and 
+** limitations under the License.
+*/
+
+#ifndef SkGlyphCache_DEFINED
+#define SkGlyphCache_DEFINED
+
+#include "SkBitmap.h"
+#include "SkChunkAlloc.h"
+#include "SkDescriptor.h"
+#include "SkScalerContext.h"
+#include "SkTemplates.h"
+
+class SkPaint;
+
+class SkGlyphCache_Globals;
+
+/** \class SkGlyphCache
+
+    This class represents a strike: a specific combination of typeface, size,
+    matrix, etc., and holds the glyphs for that strike. Calling any of the
+    getUnichar.../getGlyphID... methods will return the requested glyph,
+    either instantly if it is already cahced, or by first generating it and then
+    adding it to the strike.
+
+    The strikes are held in a global list, available to all threads. To interact
+    with one, call either VisitCache() or DetachCache().
+*/
+class SkGlyphCache {
+public:
+    /** Returns a glyph with valid fAdvance and fDevKern fields.
+        The remaining fields may be valid, but that is not guaranteed. If you
+        require those, call getUnicharMetrics or getGlyphIDMetrics instead.
+    */
+    const SkGlyph& getUnicharAdvance(SkUnichar);
+    const SkGlyph& getGlyphIDAdvance(uint16_t);
+    
+    /** Returns a glyph with all fields valid except fImage and fPath, which
+        may be null. If they are null, call findImage or findPath for those.
+        If they are not null, then they are valid.
+        
+        This call is potentially slower than the matching ...Advance call. If
+        you only need the fAdvance/fDevKern fields, call those instead.
+    */
+    const SkGlyph& getUnicharMetrics(SkUnichar);
+    const SkGlyph& getGlyphIDMetrics(uint16_t);
+    
+    /** These are variants that take the device position of the glyph. Call
+        these only if you are drawing in subpixel mode. Passing 0, 0 is
+        effectively the same as calling the variants w/o the extra params, tho
+        a tiny bit slower.
+    */
+    const SkGlyph& getUnicharMetrics(SkUnichar, SkFixed x, SkFixed y);
+    const SkGlyph& getGlyphIDMetrics(uint16_t, SkFixed x, SkFixed y);
+    
+    /** Return the image associated with the glyph. If it has not been generated
+        this will trigger that.
+    */
+    const void* findImage(const SkGlyph&);
+    /** Return the Path associated with the glyph. If it has not been generated
+        this will trigger that.
+    */
+    const SkPath* findPath(const SkGlyph&);
+
+    /** Return the vertical metrics for this strike.
+    */
+    const SkPaint::FontMetrics& getFontMetricsY() const {
+        return fFontMetricsY;
+    }
+    
+    /*  AuxProc/Data allow a client to associate data with this cache entry.
+        Multiple clients can use this, as their data is keyed with a function
+        pointer. In addition to serving as a key, the function pointer is called
+        with the data when the glyphcache object is deleted, so the client can
+        cleanup their data as well. NOTE: the auxProc must not try to access
+        this glyphcache in any way, since it may be in the process of being
+        deleted.
+    */
+    
+    //! If the proc is found, return true and set *dataPtr to its data
+    bool getAuxProcData(void (*auxProc)(void*), void** dataPtr) const;
+    //! Add a proc/data pair to the glyphcache. proc should be non-null
+    void setAuxProc(void (*auxProc)(void*), void* auxData);
+    //! If found, remove the proc/data pair from the glyphcache (does not
+    //  call the proc)
+    void removeAuxProc(void (*auxProc)(void*));
+
+    /** Find a matching cache entry, and call proc() with it. If none is found
+        create a new one. If the proc() returns true, detach the cache and
+        return it, otherwise leave it and return NULL.
+    */
+    static SkGlyphCache* VisitCache(const SkDescriptor* desc,
+                                    bool (*proc)(const SkGlyphCache*, void*),
+                                    void* context);
+    
+    /** Given a strike that was returned by either VisitCache() or DetachCache()
+        add it back into the global cache list (after which the caller should
+        not reference it anymore.
+    */
+    static void AttachCache(SkGlyphCache*);
+
+    /** Detach a strike from the global cache matching the specified descriptor.
+        Once detached, it can be queried/modified by the current thread, and
+        when finished, be reattached to the global cache with AttachCache().
+        While detached, if another request is made with the same descriptor,
+        a different strike will be generated. This is fine. It does mean we
+        can have more than 1 strike for the same descriptor, but that will
+        eventually get purged, and the win is that different thread will never
+        block each other while a strike is being used.
+    */
+    static SkGlyphCache* DetachCache(const SkDescriptor* desc) {
+        return VisitCache(desc, DetachProc, NULL);
+    }
+
+    /** Return the approximate number of bytes used by the font cache
+    */
+    static size_t GetCacheUsed();
+
+    /** This can be called to purge old font data, in an attempt to free
+        enough bytes such that the font cache is not using more than the
+        specified number of bytes. It is thread-safe, and may be called at
+        any time.
+        Return true if some amount of the cache was purged.
+    */
+    static bool SetCacheUsed(size_t bytesUsed);
+
+private:
+    SkGlyphCache(const SkDescriptor*);
+    ~SkGlyphCache();
+    
+    enum MetricsType {
+        kJustAdvance_MetricsType,
+        kFull_MetricsType
+    };
+
+    SkGlyph* lookupMetrics(uint32_t id, MetricsType);
+    static bool DetachProc(const SkGlyphCache*, void*) { return true; }
+
+    void detach(SkGlyphCache** head) {
+        if (fPrev) {
+            fPrev->fNext = fNext;
+        } else {
+            *head = fNext;
+        }
+        if (fNext) {
+            fNext->fPrev = fPrev;
+        }
+        fPrev = fNext = NULL;
+    }
+    
+    void attachToHead(SkGlyphCache** head) {
+        SkASSERT(NULL == fPrev && NULL == fNext);
+        if (*head) {
+            (*head)->fPrev = this;
+            fNext = *head;
+        }
+        *head = this;
+    }
+
+    SkGlyphCache*       fNext, *fPrev;
+    SkDescriptor*       fDesc;
+    SkScalerContext*    fScalerContext;
+    SkPaint::FontMetrics fFontMetricsY;
+
+    enum {
+        kHashBits   = 6,
+        kHashCount  = 1 << kHashBits,
+        kHashMask   = kHashCount - 1
+    };
+    SkGlyph*            fGlyphHash[kHashCount];
+    SkTDArray<SkGlyph*> fGlyphArray;
+    SkChunkAlloc        fGlyphAlloc;
+    SkChunkAlloc        fImageAlloc;
+    
+    int fMetricsCount, fAdvanceCount;
+
+    struct CharGlyphRec {
+        uint32_t    fID;    // unichar + subpixel
+        SkGlyph*    fGlyph;
+    };
+    // no reason to use the same kHashCount as fGlyphHash, but we do for now
+    CharGlyphRec    fCharToGlyphHash[kHashCount];
+    
+    enum {
+        // shift so that the top bits fall into kHashBits region
+        kShiftForHashIndex = SkGlyph::kSubShift +
+                             SkGlyph::kSubBits*2 -
+                             kHashBits
+    };
+
+    static inline unsigned ID2HashIndex(uint32_t id) {
+        return (id ^ (id >> kShiftForHashIndex)) & kHashMask;
+    }
+    
+    // used to track (approx) how much ram is tied-up in this cache
+    size_t  fMemoryUsed;
+
+    struct AuxProcRec {
+        AuxProcRec* fNext;
+        void (*fProc)(void*);
+        void* fData;
+    };
+    AuxProcRec* fAuxProcList;
+    void invokeAndRemoveAuxProcs();
+
+    // This relies on the caller to have already acquired the mutex to access the global cache
+    static size_t InternalFreeCache(SkGlyphCache_Globals*, size_t bytesNeeded);
+
+    inline static SkGlyphCache* FindTail(SkGlyphCache* head);
+    static size_t ComputeMemoryUsed(const SkGlyphCache* head);
+
+    friend class SkGlyphCache_Globals;
+};
+
+class SkAutoGlyphCache {
+public:
+    SkAutoGlyphCache(SkGlyphCache* cache) : fCache(cache) {}
+    SkAutoGlyphCache(const SkDescriptor* desc)
+    {
+        fCache = SkGlyphCache::DetachCache(desc);
+    }
+    SkAutoGlyphCache(const SkPaint& paint, const SkMatrix* matrix)
+    {
+        fCache = paint.detachCache(matrix);
+    }
+    ~SkAutoGlyphCache()
+    {
+        if (fCache)
+            SkGlyphCache::AttachCache(fCache);
+    }
+
+    SkGlyphCache*   getCache() const { return fCache; }
+
+    void release()
+    {
+        if (fCache)
+        {
+            SkGlyphCache::AttachCache(fCache);
+            fCache = NULL;
+        }
+    }
+private:
+    SkGlyphCache*   fCache;
+    
+    static bool DetachProc(const SkGlyphCache*, void*);
+};
+
+#endif
+