skia2/tools/Registry.h
Ben Wagner d5148e3314 Move SkNoncopyable to include/private.
Change-Id: I62f60ea52faeebddecacf03d9429ac3f7c516b8e
Reviewed-on: https://skia-review.googlesource.com/141823
Commit-Queue: Ben Wagner <bungeman@google.com>
Reviewed-by: Ben Wagner <bungeman@google.com>
2018-07-17 21:39:51 +00:00

59 lines
1.4 KiB
C++

/*
* 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 sk_tools_Registry_DEFINED
#define sk_tools_Registry_DEFINED
#include "SkNoncopyable.h"
#include "SkTypes.h"
namespace sk_tools {
/** 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
services, e.g. a set of image codecs.
*/
template <typename T> class Registry : SkNoncopyable {
public:
typedef T Factory;
explicit Registry(T fact) : fFact(fact) {
#ifdef SK_BUILD_FOR_ANDROID
// work-around for double-initialization bug
{
Registry* reg = gHead;
while (reg) {
if (reg == this) {
return;
}
reg = reg->fChain;
}
}
#endif
fChain = gHead;
gHead = this;
}
static const Registry* Head() { return gHead; }
const Registry* next() const { return fChain; }
const Factory& factory() const { return fFact; }
private:
Factory fFact;
Registry* fChain;
static Registry* gHead;
};
// The caller still needs to declare an instance of this somewhere
template <typename T> Registry<T>* Registry<T>::gHead;
} // namespace sk_tools
#endif