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-rw-r--r--base/ref_counted.h292
1 files changed, 3 insertions, 289 deletions
diff --git a/base/ref_counted.h b/base/ref_counted.h
index a6ebfb7..5f23b29 100644
--- a/base/ref_counted.h
+++ b/base/ref_counted.h
@@ -6,294 +6,8 @@
#define BASE_REF_COUNTED_H_
#pragma once
-#include "base/atomic_ref_count.h"
-#include "base/base_api.h"
-#include "base/threading/thread_collision_warner.h"
-
-namespace base {
-
-namespace subtle {
-
-class BASE_API RefCountedBase {
- public:
- static bool ImplementsThreadSafeReferenceCounting() { return false; }
-
- bool HasOneRef() const { return ref_count_ == 1; }
-
- protected:
- RefCountedBase();
- ~RefCountedBase();
-
- void AddRef() const;
-
- // Returns true if the object should self-delete.
- bool Release() const;
-
- private:
- mutable int ref_count_;
-#ifndef NDEBUG
- mutable bool in_dtor_;
-#endif
-
- DFAKE_MUTEX(add_release_);
-
- DISALLOW_COPY_AND_ASSIGN(RefCountedBase);
-};
-
-class BASE_API RefCountedThreadSafeBase {
- public:
- static bool ImplementsThreadSafeReferenceCounting() { return true; }
-
- bool HasOneRef() const;
-
- protected:
- RefCountedThreadSafeBase();
- ~RefCountedThreadSafeBase();
-
- void AddRef() const;
-
- // Returns true if the object should self-delete.
- bool Release() const;
-
- private:
- mutable AtomicRefCount ref_count_;
-#ifndef NDEBUG
- mutable bool in_dtor_;
-#endif
-
- DISALLOW_COPY_AND_ASSIGN(RefCountedThreadSafeBase);
-};
-
-} // namespace subtle
-
-//
-// A base class for reference counted classes. Otherwise, known as a cheap
-// knock-off of WebKit's RefCounted<T> class. To use this guy just extend your
-// class from it like so:
-//
-// class MyFoo : public base::RefCounted<MyFoo> {
-// ...
-// private:
-// friend class base::RefCounted<MyFoo>;
-// ~MyFoo();
-// };
-//
-// You should always make your destructor private, to avoid any code deleting
-// the object accidently while there are references to it.
-template <class T>
-class RefCounted : public subtle::RefCountedBase {
- public:
- RefCounted() { }
- ~RefCounted() { }
-
- void AddRef() const {
- subtle::RefCountedBase::AddRef();
- }
-
- void Release() const {
- if (subtle::RefCountedBase::Release()) {
- delete static_cast<const T*>(this);
- }
- }
-
- private:
- DISALLOW_COPY_AND_ASSIGN(RefCounted<T>);
-};
-
-// Forward declaration.
-template <class T, typename Traits> class RefCountedThreadSafe;
-
-// Default traits for RefCountedThreadSafe<T>. Deletes the object when its ref
-// count reaches 0. Overload to delete it on a different thread etc.
-template<typename T>
-struct DefaultRefCountedThreadSafeTraits {
- static void Destruct(const T* x) {
- // Delete through RefCountedThreadSafe to make child classes only need to be
- // friend with RefCountedThreadSafe instead of this struct, which is an
- // implementation detail.
- RefCountedThreadSafe<T,
- DefaultRefCountedThreadSafeTraits>::DeleteInternal(x);
- }
-};
-
-//
-// A thread-safe variant of RefCounted<T>
-//
-// class MyFoo : public base::RefCountedThreadSafe<MyFoo> {
-// ...
-// };
-//
-// If you're using the default trait, then you should add compile time
-// asserts that no one else is deleting your object. i.e.
-// private:
-// friend class base::RefCountedThreadSafe<MyFoo>;
-// ~MyFoo();
-template <class T, typename Traits = DefaultRefCountedThreadSafeTraits<T> >
-class RefCountedThreadSafe : public subtle::RefCountedThreadSafeBase {
- public:
- RefCountedThreadSafe() { }
- ~RefCountedThreadSafe() { }
-
- void AddRef() const {
- subtle::RefCountedThreadSafeBase::AddRef();
- }
-
- void Release() const {
- if (subtle::RefCountedThreadSafeBase::Release()) {
- Traits::Destruct(static_cast<const T*>(this));
- }
- }
-
- private:
- friend struct DefaultRefCountedThreadSafeTraits<T>;
- static void DeleteInternal(const T* x) { delete x; }
-
- DISALLOW_COPY_AND_ASSIGN(RefCountedThreadSafe);
-};
-
-//
-// A wrapper for some piece of data so we can place other things in
-// scoped_refptrs<>.
-//
-template<typename T>
-class RefCountedData : public base::RefCounted< base::RefCountedData<T> > {
- public:
- RefCountedData() : data() {}
- RefCountedData(const T& in_value) : data(in_value) {}
-
- T data;
-};
-
-} // namespace base
-
-//
-// A smart pointer class for reference counted objects. Use this class instead
-// of calling AddRef and Release manually on a reference counted object to
-// avoid common memory leaks caused by forgetting to Release an object
-// reference. Sample usage:
-//
-// class MyFoo : public RefCounted<MyFoo> {
-// ...
-// };
-//
-// void some_function() {
-// scoped_refptr<MyFoo> foo = new MyFoo();
-// foo->Method(param);
-// // |foo| is released when this function returns
-// }
-//
-// void some_other_function() {
-// scoped_refptr<MyFoo> foo = new MyFoo();
-// ...
-// foo = NULL; // explicitly releases |foo|
-// ...
-// if (foo)
-// foo->Method(param);
-// }
-//
-// The above examples show how scoped_refptr<T> acts like a pointer to T.
-// Given two scoped_refptr<T> classes, it is also possible to exchange
-// references between the two objects, like so:
-//
-// {
-// scoped_refptr<MyFoo> a = new MyFoo();
-// scoped_refptr<MyFoo> b;
-//
-// b.swap(a);
-// // now, |b| references the MyFoo object, and |a| references NULL.
-// }
-//
-// To make both |a| and |b| in the above example reference the same MyFoo
-// object, simply use the assignment operator:
-//
-// {
-// scoped_refptr<MyFoo> a = new MyFoo();
-// scoped_refptr<MyFoo> b;
-//
-// b = a;
-// // now, |a| and |b| each own a reference to the same MyFoo object.
-// }
-//
-template <class T>
-class scoped_refptr {
- public:
- scoped_refptr() : ptr_(NULL) {
- }
-
- scoped_refptr(T* p) : ptr_(p) {
- if (ptr_)
- ptr_->AddRef();
- }
-
- scoped_refptr(const scoped_refptr<T>& r) : ptr_(r.ptr_) {
- if (ptr_)
- ptr_->AddRef();
- }
-
- template <typename U>
- scoped_refptr(const scoped_refptr<U>& r) : ptr_(r.get()) {
- if (ptr_)
- ptr_->AddRef();
- }
-
- ~scoped_refptr() {
- if (ptr_)
- ptr_->Release();
- }
-
- T* get() const { return ptr_; }
- operator T*() const { return ptr_; }
- T* operator->() const { return ptr_; }
-
- // Release a pointer.
- // The return value is the current pointer held by this object.
- // If this object holds a NULL pointer, the return value is NULL.
- // After this operation, this object will hold a NULL pointer,
- // and will not own the object any more.
- T* release() {
- T* retVal = ptr_;
- ptr_ = NULL;
- return retVal;
- }
-
- scoped_refptr<T>& operator=(T* p) {
- // AddRef first so that self assignment should work
- if (p)
- p->AddRef();
- if (ptr_ )
- ptr_ ->Release();
- ptr_ = p;
- return *this;
- }
-
- scoped_refptr<T>& operator=(const scoped_refptr<T>& r) {
- return *this = r.ptr_;
- }
-
- template <typename U>
- scoped_refptr<T>& operator=(const scoped_refptr<U>& r) {
- return *this = r.get();
- }
-
- void swap(T** pp) {
- T* p = ptr_;
- ptr_ = *pp;
- *pp = p;
- }
-
- void swap(scoped_refptr<T>& r) {
- swap(&r.ptr_);
- }
-
- protected:
- T* ptr_;
-};
-
-// Handy utility for creating a scoped_refptr<T> out of a T* explicitly without
-// having to retype all the template arguments
-template <typename T>
-scoped_refptr<T> make_scoped_refptr(T* t) {
- return scoped_refptr<T>(t);
-}
+// FIXME: Remove this header when third_party/leveldb is fixed to not rely on
+// it.
+#include "base/memory/ref_counted.h"
#endif // BASE_REF_COUNTED_H_