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diff --git a/chromium/net/third_party/quiche/src/quiche/common/platform/api/quiche_reference_counted.h b/chromium/net/third_party/quiche/src/quiche/common/platform/api/quiche_reference_counted.h
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+// Copyright (c) 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef QUICHE_COMMON_PLATFORM_API_QUICHE_REFERENCE_COUNTED_H_
+#define QUICHE_COMMON_PLATFORM_API_QUICHE_REFERENCE_COUNTED_H_
+
+#include "quiche_platform_impl/quiche_reference_counted_impl.h"
+#include "quiche/common/platform/api/quiche_export.h"
+
+namespace quiche {
+
+// Base class for explicitly reference-counted objects in QUIC.
+class QUICHE_EXPORT_PRIVATE QuicheReferenceCounted
+ : public QuicheReferenceCountedImpl {
+ public:
+ QuicheReferenceCounted() {}
+
+ protected:
+ ~QuicheReferenceCounted() override {}
+};
+
+// A class representing a reference counted pointer in QUIC.
+//
+// Construct or initialize QuicheReferenceCountedPointer from raw pointer. Here
+// raw pointer MUST be a newly created object. Reference count of a newly
+// created object is undefined, but that will be 1 after being added to
+// QuicheReferenceCountedPointer.
+// QuicheReferenceCountedPointer is used as a local variable.
+// QuicheReferenceCountedPointer<T> r_ptr(new T());
+// or, equivalently:
+// QuicheReferenceCountedPointer<T> r_ptr;
+// T* p = new T();
+// r_ptr = T;
+//
+// QuicheReferenceCountedPointer is used as a member variable:
+// MyClass::MyClass() : r_ptr(new T()) {}
+//
+// This is WRONG, since *p is not guaranteed to be newly created:
+// MyClass::MyClass(T* p) : r_ptr(p) {}
+//
+// Given an existing QuicheReferenceCountedPointer, create a duplicate that has
+// its own reference on the object:
+// QuicheReferenceCountedPointer<T> r_ptr_b(r_ptr_a);
+// or, equivalently:
+// QuicheReferenceCountedPointer<T> r_ptr_b = r_ptr_a;
+//
+// Given an existing QuicheReferenceCountedPointer, create a
+// QuicheReferenceCountedPointer that adopts the reference:
+// QuicheReferenceCountedPointer<T> r_ptr_b(std::move(r_ptr_a));
+// or, equivalently:
+// QuicheReferenceCountedPointer<T> r_ptr_b = std::move(r_ptr_a);
+
+template <class T>
+class QUICHE_NO_EXPORT QuicheReferenceCountedPointer {
+ public:
+ QuicheReferenceCountedPointer() = default;
+
+ // Constructor from raw pointer |p|. This guarantees that the reference count
+ // of *p is 1. This should be only called when a new object is created.
+ // Calling this on an already existent object does not increase its reference
+ // count.
+ explicit QuicheReferenceCountedPointer(T* p) : impl_(p) {}
+
+ // Allows implicit conversion from nullptr.
+ QuicheReferenceCountedPointer(std::nullptr_t) : impl_(nullptr) {} // NOLINT
+
+ // Copy and copy conversion constructors. It does not take the reference away
+ // from |other| and they each end up with their own reference.
+ template <typename U>
+ QuicheReferenceCountedPointer( // NOLINT
+ const QuicheReferenceCountedPointer<U>& other)
+ : impl_(other.impl()) {}
+ QuicheReferenceCountedPointer(const QuicheReferenceCountedPointer& other)
+ : impl_(other.impl()) {}
+
+ // Move constructors. After move, it adopts the reference from |other|.
+ template <typename U>
+ QuicheReferenceCountedPointer(
+ QuicheReferenceCountedPointer<U>&& other) // NOLINT
+ : impl_(std::move(other.impl())) {}
+ QuicheReferenceCountedPointer(QuicheReferenceCountedPointer&& other)
+ : impl_(std::move(other.impl())) {}
+
+ ~QuicheReferenceCountedPointer() = default;
+
+ // Copy assignments.
+ QuicheReferenceCountedPointer& operator=(
+ const QuicheReferenceCountedPointer& other) {
+ impl_ = other.impl();
+ return *this;
+ }
+ template <typename U>
+ QuicheReferenceCountedPointer<T>& operator=(
+ const QuicheReferenceCountedPointer<U>& other) {
+ impl_ = other.impl();
+ return *this;
+ }
+
+ // Move assignments.
+ QuicheReferenceCountedPointer& operator=(
+ QuicheReferenceCountedPointer&& other) {
+ impl_ = std::move(other.impl());
+ return *this;
+ }
+ template <typename U>
+ QuicheReferenceCountedPointer<T>& operator=(
+ QuicheReferenceCountedPointer<U>&& other) {
+ impl_ = std::move(other.impl());
+ return *this;
+ }
+
+ // Accessors for the referenced object.
+ // operator*() and operator->() will assert() if there is no current object.
+ T& operator*() const { return *impl_; }
+ T* operator->() const { return impl_.get(); }
+
+ explicit operator bool() const { return static_cast<bool>(impl_); }
+
+ // Assignment operator on raw pointer. Drops a reference to current pointee,
+ // if any, and replaces it with |p|. This guarantees that the reference count
+ // of *p is 1. This should only be used when a new object is created. Calling
+ // this on an already existent object is undefined behavior.
+ QuicheReferenceCountedPointer<T>& operator=(T* p) {
+ impl_ = p;
+ return *this;
+ }
+
+ // Returns the raw pointer with no change in reference count.
+ T* get() const { return impl_.get(); }
+
+ QuicheReferenceCountedPointerImpl<T>& impl() { return impl_; }
+ const QuicheReferenceCountedPointerImpl<T>& impl() const { return impl_; }
+
+ // Comparisons against same type.
+ friend bool operator==(const QuicheReferenceCountedPointer& a,
+ const QuicheReferenceCountedPointer& b) {
+ return a.get() == b.get();
+ }
+ friend bool operator!=(const QuicheReferenceCountedPointer& a,
+ const QuicheReferenceCountedPointer& b) {
+ return a.get() != b.get();
+ }
+
+ // Comparisons against nullptr.
+ friend bool operator==(const QuicheReferenceCountedPointer& a,
+ std::nullptr_t) {
+ return a.get() == nullptr;
+ }
+ friend bool operator==(std::nullptr_t,
+ const QuicheReferenceCountedPointer& b) {
+ return nullptr == b.get();
+ }
+ friend bool operator!=(const QuicheReferenceCountedPointer& a,
+ std::nullptr_t) {
+ return a.get() != nullptr;
+ }
+ friend bool operator!=(std::nullptr_t,
+ const QuicheReferenceCountedPointer& b) {
+ return nullptr != b.get();
+ }
+
+ private:
+ QuicheReferenceCountedPointerImpl<T> impl_;
+};
+
+} // namespace quiche
+
+#endif // QUICHE_COMMON_PLATFORM_API_QUICHE_REFERENCE_COUNTED_H_