Rewrite SkTRegistry to take any trivially-copyable type.

include/core/SkTRegistry.h

 
 /*
  * Copyright 2009 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 SkTRegistry_DEFINED
 #define SkTRegistry_DEFINED
 
 #include "SkTypes.h"
 
 /** Template class that registers itself (in the constructor) into a linked-list
-    and provides a function-pointer. This can be used to auto-register a set of
+    and provides a user-defined type. This can be used to auto-register a set of
     services, e.g. a set of image codecs.
  */
-template <typename T, typename P> class SkTRegistry : SkNoncopyable {
+template <typename T> class SkTRegistry : SkNoncopyable {
 public:
-    typedef T (*Factory)(P);
-
-    SkTRegistry(Factory fact) {
+    typedef T Data;

[scroggo, 2013/09/04 15:40:21]

Would it make sense to write a partial specialization for returning a factory?
That would have the benefit that you could call a function called factory()
rather than a function called data().

+    explicit SkTRegistry(T data) {

[reed1, 2013/09/04 15:15:23]

(const T&) so we don't force the caller to make a copy? (trivial I know, but I
had to ask)

[mtklein, 2013/09/04 16:36:46]

As we talked.

 #ifdef SK_BUILD_FOR_ANDROID
         // work-around for double-initialization bug
         {
             SkTRegistry* reg = gHead;
             while (reg) {
                 if (reg == this) {
                     return;
                 }
                 reg = reg->fChain;
             }
         }
 #endif
-        fFact = fact;
+        fData  = data;
         fChain = gHead;
-        gHead = this;
+        gHead  = this;
     }
 
     static const SkTRegistry* Head() { return gHead; }
 
     const SkTRegistry* next() const { return fChain; }
-    Factory factory() const { return fFact; }
+    Data data() const { return fData; } // fix

[reed1, 2013/09/04 15:15:23]

const Data& data() const { ... }   ?

[mtklein, 2013/09/04 16:36:46]

Done.

 
 private:
-    Factory      fFact;
+    Data          fData;
     SkTRegistry* fChain;
 
     static SkTRegistry* gHead;
 };
 
 // The caller still needs to declare an instance of this somewhere
-template <typename T, typename P> SkTRegistry<T, P>* SkTRegistry<T, P>::gHead;
+template <typename T> SkTRegistry<T>* SkTRegistry<T>::gHead;
 
 #endif