Checking structure sizes before reading them from memory to avoid overflowing the buffer's stream.

include/core/SkRRect.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 SkRRect_DEFINED
 #define SkRRect_DEFINED
 
@@ skipping 226 matching lines @@
 
     enum {
         kSizeInMemory = 12 * sizeof(SkScalar)
     };
 
     /**
      *  Write the rrect into the specified buffer. This is guaranteed to always
      *  write kSizeInMemory bytes, and that value is guaranteed to always be
      *  a multiple of 4. Return kSizeInMemory.
      */
-    uint32_t writeToMemory(void* buffer) const;
+    size_t writeToMemory(void* buffer) const;
 
     /**
-     *  Read the rrect from the specified buffer. This is guaranteed to always
-     *  read kSizeInMemory bytes, and that value is guaranteed to always be
-     *  a multiple of 4. Return kSizeInMemory.
+     * Reads the rrect from the specified buffer
+     *
+     * If the specified buffer is large enough, this will read kSizeInMemory bytes,
+     * and that value is guaranteed to always be a multiple of 4.
+     *
+     * @param buffer Memory to read from
+     * @param length Amount of memory available in the buffer
+     * @return number of bytes read (must be a multiple of 4) or
+     *         0 if there was not enough memory available
      */
-    uint32_t readFromMemory(const void* buffer);
+    size_t readFromMemory(const void* buffer, size_t length);
 
 private:
     SkRect fRect;
     // Radii order is UL, UR, LR, LL. Use Corner enum to index into fRadii[]
     SkVector fRadii[4];
     mutable Type fType;
     // TODO: add padding so we can use memcpy for flattening and not copy
     // uninitialized data
 
     void computeType() const;
     bool checkCornerContainment(SkScalar x, SkScalar y) const;
 
     // to access fRadii directly
     friend class SkPath;
 };
 
 #endif