1b40a9a8af
This CL makes AddRef() and Release() const member methods and the refcount integer mutable. This is reasonable, because they only manage the lifetime of the object, and this is also how it's done in Chromium.
The purpose is to be able to capture a const pointer in a scoped_refptr, which is currenty impossible. The practial problem this CL solves is this:
void Foo::Bar() const {}
rtc::Callback0<void> Foo::MakeClosure() const {
return rtc::Bind(&Foo::Bar, this);
}
We currently capture |this| as const Foo*. With this CL, |this| will be captured as scoped_refptr<const Foo>.
A test is also added in bind_unittest to check this behaviour.
BUG=webrtc:5065
R=perkj@webrtc.org, tommi@webrtc.org
Review URL: https://codereview.webrtc.org/1403683004 .
Cr-Commit-Position: refs/heads/master@{#10253}
83 lines
2.3 KiB
C++
83 lines
2.3 KiB
C++
/*
|
|
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
|
|
*
|
|
* Use of this source code is governed by a BSD-style license
|
|
* that can be found in the LICENSE file in the root of the source
|
|
* tree. An additional intellectual property rights grant can be found
|
|
* in the file PATENTS. All contributing project authors may
|
|
* be found in the AUTHORS file in the root of the source tree.
|
|
*/
|
|
|
|
#ifndef SYSTEM_WRAPPERS_INTERFACE_REF_COUNT_H_
|
|
#define SYSTEM_WRAPPERS_INTERFACE_REF_COUNT_H_
|
|
|
|
#include "webrtc/system_wrappers/interface/atomic32.h"
|
|
|
|
namespace webrtc {
|
|
|
|
// This class can be used for instantiating
|
|
// reference counted objects.
|
|
// int32_t AddRef() and int32_t Release().
|
|
// Usage:
|
|
// RefCountImpl<T>* implementation = new RefCountImpl<T>(p);
|
|
//
|
|
// Example:
|
|
// class MyInterface {
|
|
// public:
|
|
// virtual void DoSomething() = 0;
|
|
// virtual int32_t AddRef() = 0;
|
|
// virtual int32_t Release() = 0:
|
|
// private:
|
|
// virtual ~MyInterface(){};
|
|
// }
|
|
// class MyImplementation : public MyInterface {
|
|
// public:
|
|
// virtual DoSomething() { printf("hello"); };
|
|
// };
|
|
// MyImplementation* CreateMyImplementation() {
|
|
// RefCountImpl<MyImplementation>* implementation =
|
|
// new RefCountImpl<MyImplementation>();
|
|
// return implementation;
|
|
// }
|
|
|
|
template <class T>
|
|
class RefCountImpl : public T {
|
|
public:
|
|
RefCountImpl() : ref_count_(0) {}
|
|
|
|
template<typename P>
|
|
explicit RefCountImpl(P p) : T(p), ref_count_(0) {}
|
|
|
|
template<typename P1, typename P2>
|
|
RefCountImpl(P1 p1, P2 p2) : T(p1, p2), ref_count_(0) {}
|
|
|
|
template<typename P1, typename P2, typename P3>
|
|
RefCountImpl(P1 p1, P2 p2, P3 p3) : T(p1, p2, p3), ref_count_(0) {}
|
|
|
|
template<typename P1, typename P2, typename P3, typename P4>
|
|
RefCountImpl(P1 p1, P2 p2, P3 p3, P4 p4) : T(p1, p2, p3, p4), ref_count_(0) {}
|
|
|
|
template<typename P1, typename P2, typename P3, typename P4, typename P5>
|
|
RefCountImpl(P1 p1, P2 p2, P3 p3, P4 p4, P5 p5)
|
|
: T(p1, p2, p3, p4, p5), ref_count_(0) {}
|
|
|
|
int32_t AddRef() const override {
|
|
return ++ref_count_;
|
|
}
|
|
|
|
int32_t Release() const override {
|
|
int32_t ref_count;
|
|
ref_count = --ref_count_;
|
|
if (ref_count == 0)
|
|
delete this;
|
|
return ref_count;
|
|
}
|
|
|
|
protected:
|
|
mutable Atomic32 ref_count_;
|
|
};
|
|
|
|
} // namespace webrtc
|
|
|
|
#endif // SYSTEM_WRAPPERS_INTERFACE_REF_COUNT_H_
|