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-rw-r--r--third_party/chromium/base/memory/ptr_util.h74
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diff --git a/third_party/chromium/base/memory/ptr_util.h b/third_party/chromium/base/memory/ptr_util.h
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+// Copyright 2015 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 BASE_MEMORY_PTR_UTIL_H_
+#define BASE_MEMORY_PTR_UTIL_H_
+
+#include <memory>
+#include <utility>
+
+namespace base {
+
+// Helper to transfer ownership of a raw pointer to a std::unique_ptr<T>.
+// Note that std::unique_ptr<T> has very different semantics from
+// std::unique_ptr<T[]>: do not use this helper for array allocations.
+template <typename T>
+std::unique_ptr<T> WrapUnique(T* ptr) {
+ return std::unique_ptr<T>(ptr);
+}
+
+namespace internal {
+
+template <typename T>
+struct MakeUniqueResult {
+ using Scalar = std::unique_ptr<T>;
+};
+
+template <typename T>
+struct MakeUniqueResult<T[]> {
+ using Array = std::unique_ptr<T[]>;
+};
+
+template <typename T, size_t N>
+struct MakeUniqueResult<T[N]> {
+ using Invalid = void;
+};
+
+} // namespace internal
+
+// Helper to construct an object wrapped in a std::unique_ptr. This is an
+// implementation of C++14's std::make_unique that can be used in Chrome.
+//
+// MakeUnique<T>(args) should be preferred over WrapUnique(new T(args)): bare
+// calls to `new` should be treated with scrutiny.
+//
+// Usage:
+// // ptr is a std::unique_ptr<std::string>
+// auto ptr = MakeUnique<std::string>("hello world!");
+//
+// // arr is a std::unique_ptr<int[]>
+// auto arr = MakeUnique<int[]>(5);
+
+// Overload for non-array types. Arguments are forwarded to T's constructor.
+template <typename T, typename... Args>
+typename internal::MakeUniqueResult<T>::Scalar MakeUnique(Args&&... args) {
+ return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
+}
+
+// Overload for array types of unknown bound, e.g. T[]. The array is allocated
+// with `new T[n]()` and value-initialized: note that this is distinct from
+// `new T[n]`, which default-initializes.
+template <typename T>
+typename internal::MakeUniqueResult<T>::Array MakeUnique(size_t size) {
+ return std::unique_ptr<T>(new typename std::remove_extent<T>::type[size]());
+}
+
+// Overload to reject array types of known bound, e.g. T[n].
+template <typename T, typename... Args>
+typename internal::MakeUniqueResult<T>::Invalid MakeUnique(Args&&... args) =
+ delete;
+
+} // namespace base
+
+#endif // BASE_MEMORY_PTR_UTIL_H_