SK_ONCE for SkData

include/core/SkPathRef.h

 
 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkPathRef_DEFINED
 #define SkPathRef_DEFINED
@@ skipping 90 matching lines @@
         SkPathRef* pathRef() { return fPathRef; }
 
     private:
         SkPathRef* fPathRef;
     };
 
 public:
     /**
      * Gets a path ref with no verbs or points.
      */
-    static SkPathRef* CreateEmpty() {
-        static SkPathRef* gEmptyPathRef;
-        if (!gEmptyPathRef) {
-            gEmptyPathRef = SkNEW(SkPathRef); // leak!
-            gEmptyPathRef->computeBounds();   // Premptively avoid a race to clear fBoundsIsDirty.
-        }
-        return SkRef(gEmptyPathRef);
-    }
+    static SkPathRef* CreateEmpty();
 
     /**
      *  Returns true if all of the points in this path are finite, meaning there
      *  are no infinities and no NaNs.
      */
     bool isFinite() const {
         if (fBoundsIsDirty) {
             this->computeBounds();
         }
         return SkToBool(fIsFinite);
@@ skipping 261 matching lines @@
     /**
      * Gets an ID that uniquely identifies the contents of the path ref. If two path refs have the
      * same ID then they have the same verbs and points. However, two path refs may have the same
      * contents but different genIDs. Zero is reserved and means an ID has not yet been determined
      * for the path ref.
      */
     int32_t genID() const;
 
     SkDEBUGCODE(void validate() const;)
 
+    /**
+     * Called the first time someone calls CreateEmpty to actually create the singleton.
+     */
+    static void CreateEmptyImpl(SkPathRef** empty);
+
     enum {
         kMinSize = 256,
     };
 
     mutable SkRect      fBounds;
     mutable uint8_t     fBoundsIsDirty;
     mutable SkBool8     fIsFinite;    // only meaningful if bounds are valid
 
     SkPoint*            fPoints; // points to begining of the allocation
     uint8_t*            fVerbs; // points just past the end of the allocation (verbs grow backwards)
     int                 fVerbCnt;
     int                 fPointCnt;
     size_t              fFreeSpace; // redundant but saves computation
     SkTDArray<SkScalar> fConicWeights;
 
     enum {
         kEmptyGenID = 1, // GenID reserved for path ref with zero points and zero verbs.
     };
     mutable int32_t     fGenerationID;
     SkDEBUGCODE(int32_t fEditorsAttached;) // assert that only one editor in use at any time.
 
     typedef SkRefCnt INHERITED;
 };
 
 #endif