Initial error handling code

include/core/SkFlattenable.h

 
 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef SkFlattenable_DEFINED
 #define SkFlattenable_DEFINED
 
 #include "SkRefCnt.h"
 
 class SkFlattenableReadBuffer;
 class SkFlattenableWriteBuffer;
 
 #define SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(flattenable) \
-        SkFlattenable::Registrar(#flattenable, flattenable::CreateProc);
+        SkFlattenable::Registrar(#flattenable, flattenable::CreateProc, flattenable::GetType());
 
 #define SK_DECLARE_FLATTENABLE_REGISTRAR_GROUP() static void InitializeFlattenables();
 
 #define SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(flattenable) \
     void flattenable::InitializeFlattenables() {
 
 #define SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END \
     }
 
 #define SK_DECLARE_UNFLATTENABLE_OBJECT() \
     virtual Factory getFactory() SK_OVERRIDE { return NULL; }
 
 #define SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(flattenable) \
     virtual Factory getFactory() SK_OVERRIDE { return CreateProc; } \
     static SkFlattenable* CreateProc(SkFlattenableReadBuffer& buffer) { \
         return SkNEW_ARGS(flattenable, (buffer)); \
     }
 
+/** For SkFlattenable derived objects with a valid type
+    This macro should only be used in base class objects in core
+  */
+#define SK_DEFINE_FLATTENABLE_TYPE(flattenable) \
+    static Type GetType() { \

[Stephen White, 2013/10/17 15:27:56]

+1 for the scoped enum. I like it! But I think this function should be
GetFlattenableType(), in order to avoid polluting the subclass's namespace with
something that sounds pretty generic. GetType() could imply it was the derived
class's type, where in actuality it's the base class's.

[sugoi1, 2013/10/17 15:33:55]

Done.

+        return k##flattenable##_Type; \
+    }
+
 /** \class SkFlattenable
 
  SkFlattenable is the base class for objects that need to be flattened
  into a data stream for either transport or as part of the key to the
  font cache.
  */
 class SK_API SkFlattenable : public SkRefCnt {
 public:
+    enum Type {
+        kSkColorFilter_Type,
+        kSkDrawLooper_Type,
+        kSkImageFilter_Type,
+        kSkMaskFilter_Type,
+        kSkPathEffect_Type,
+        kSkPixelRef_Type,
+        kSkRasterizer_Type,
+        kSkShader_Type,
+        kSkUnitMapper_Type,
+        kSkXfermode_Type,
+    };
+
     SK_DECLARE_INST_COUNT(SkFlattenable)
 
     typedef SkFlattenable* (*Factory)(SkFlattenableReadBuffer&);
 
     SkFlattenable() {}
 
     /** Implement this to return a factory function pointer that can be called
      to recreate your class given a buffer (previously written to by your
      override of flatten().
      */
     virtual Factory getFactory() = 0;
 
+    /** Returns the name of the object's class
+      */
+    const char* getTypeName() { return FactoryToName(getFactory()); }
+
     static Factory NameToFactory(const char name[]);
     static const char* FactoryToName(Factory);
-    static void Register(const char name[], Factory);
+    static bool NameToType(const char name[], Type* type);
+
+    static void Register(const char name[], Factory, Type);
 
     class Registrar {
     public:
-        Registrar(const char name[], Factory factory) {
-            SkFlattenable::Register(name, factory);
+        Registrar(const char name[], Factory factory, Type type) {
+            SkFlattenable::Register(name, factory, type);
         }
     };
 
 protected:
     SkFlattenable(SkFlattenableReadBuffer&) {}
     /** Override this to write data specific to your subclass into the buffer,
      being sure to call your super-class' version first. This data will later
      be passed to your Factory function, returned by getFactory().
      */
     virtual void flatten(SkFlattenableWriteBuffer&) const;
 
 private:
-    static void InitializeFlattenables();
+    static void InitializeFlattenablesIfNeeded();
 
     friend class SkGraphics;
     friend class SkFlattenableWriteBuffer;
 
     typedef SkRefCnt INHERITED;
 };
 
 #endif