Make the fuchsia mojo/public repo the source of truth.

mojo/public/cpp/bindings/struct_ptr.h

-// Copyright 2014 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 MOJO_PUBLIC_CPP_BINDINGS_STRUCT_PTR_H_
-#define MOJO_PUBLIC_CPP_BINDINGS_STRUCT_PTR_H_
-
-#include <cstddef>
-#include <memory>
-#include <new>
-
-#include "mojo/public/cpp/bindings/type_converter.h"
-#include "mojo/public/cpp/environment/logging.h"
-#include "mojo/public/cpp/system/macros.h"
-
-namespace mojo {
-namespace internal {
-
-template <typename Struct>
-class StructHelper {
- public:
-  template <typename Ptr>
-  static void Initialize(Ptr* ptr) {
-    ptr->Initialize();
-  }
-};
-
-}  // namespace internal
-
-// Smart pointer wrapping a mojom structure or union, with move-only semantics.
-template <typename Struct>
-class StructPtr {
- public:
-  StructPtr() {}
-  StructPtr(std::nullptr_t) {}
-
-  ~StructPtr() {}
-
-  StructPtr& operator=(std::nullptr_t) {
-    reset();
-    return *this;
-  }
-
-  StructPtr(StructPtr&& other) { Take(&other); }
-  StructPtr& operator=(StructPtr&& other) {
-    Take(&other);
-    return *this;
-  }
-
-  template <typename U>
-  U To() const {
-    return TypeConverter<U, StructPtr>::Convert(*this);
-  }
-
-  void reset() { ptr_.reset(); }
-
-  // Tests as true if non-null, false if null.
-  explicit operator bool() const { return !!ptr_; }
-
-  bool is_null() const { return !ptr_; }
-
-  Struct& operator*() const {
-    MOJO_DCHECK(ptr_);
-    return *ptr_;
-  }
-  Struct* operator->() const {
-    MOJO_DCHECK(ptr_);
-    return ptr_.get();
-  }
-  Struct* get() const { return ptr_.get(); }
-
-  void Swap(StructPtr* other) { std::swap(ptr_, other->ptr_); }
-
-  // Please note that calling this method will fail compilation if the value
-  // type |Struct| doesn't have a Clone() method defined (which usually means
-  // that it contains Mojo handles).
-  StructPtr Clone() const { return is_null() ? StructPtr() : ptr_->Clone(); }
-
-  bool Equals(const StructPtr& other) const {
-    if (is_null() || other.is_null())
-      return is_null() && other.is_null();
-    return ptr_->Equals(*other.ptr_);
-  }
-
- private:
-  friend class internal::StructHelper<Struct>;
-  void Initialize() {
-    MOJO_DCHECK(!ptr_);
-    ptr_.reset(new Struct());
-  }
-
-  void Take(StructPtr* other) {
-    reset();
-    Swap(other);
-  }
-
-  std::unique_ptr<Struct> ptr_;
-
-  MOJO_MOVE_ONLY_TYPE(StructPtr);
-};
-
-// Designed to be used when Struct is small and copyable. Unions are always
-// InlinedStructPtr in practice.
-template <typename Struct>
-class InlinedStructPtr {
- public:
-  InlinedStructPtr() : is_null_(true) {}
-  InlinedStructPtr(std::nullptr_t) : is_null_(true) {}
-
-  ~InlinedStructPtr() {}
-
-  InlinedStructPtr& operator=(std::nullptr_t) {
-    reset();
-    return *this;
-  }
-
-  InlinedStructPtr(InlinedStructPtr&& other) : is_null_(true) { Take(&other); }
-  InlinedStructPtr& operator=(InlinedStructPtr&& other) {
-    Take(&other);
-    return *this;
-  }
-
-  template <typename U>
-  U To() const {
-    return TypeConverter<U, InlinedStructPtr>::Convert(*this);
-  }
-
-  void reset() {
-    is_null_ = true;
-    value_. ~Struct();
-    new (&value_) Struct();
-  }
-
-  // Tests as true if non-null, false if null.
-  explicit operator bool() const { return !is_null_; }
-
-  bool is_null() const { return is_null_; }
-
-  Struct& operator*() const {
-    MOJO_DCHECK(!is_null_);
-    return value_;
-  }
-  Struct* operator->() const {
-    MOJO_DCHECK(!is_null_);
-    return &value_;
-  }
-  Struct* get() const { return is_null() ? nullptr : &value_; }
-
-  void Swap(InlinedStructPtr* other) {
-    std::swap(value_, other->value_);
-    std::swap(is_null_, other->is_null_);
-  }
-
-  InlinedStructPtr Clone() const {
-    return is_null() ? InlinedStructPtr() : value_.Clone();
-  }
-  bool Equals(const InlinedStructPtr& other) const {
-    if (is_null() || other.is_null())
-      return is_null() && other.is_null();
-    return value_.Equals(other.value_);
-  }
-
- private:
-  friend class internal::StructHelper<Struct>;
-  void Initialize() { is_null_ = false; }
-
-  void Take(InlinedStructPtr* other) {
-    reset();
-    Swap(other);
-  }
-
-  mutable Struct value_;
-  bool is_null_;
-
-  MOJO_MOVE_ONLY_TYPE(InlinedStructPtr);
-};
-
-}  // namespace mojo
-
-#endif  // MOJO_PUBLIC_CPP_BINDINGS_STRUCT_PTR_H_