gecko-dev/mfbt/UniquePtrExtensions.h
Nathan Froyd 556bde5629 Bug 1252195 - part 1 - implement UniqueFreePtr; r=Waldo
Just like UniquePtr<T>, except that we're going to delete the allocated
memory with |free()|.
2016-02-29 10:29:13 -05:00

58 lines
1.5 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* Useful extensions to UniquePtr. */
#ifndef mozilla_UniquePtrExtensions_h
#define mozilla_UniquePtrExtensions_h
#include "mozilla/fallible.h"
#include "mozilla/UniquePtr.h"
namespace mozilla {
/**
* MakeUniqueFallible works exactly like MakeUnique, except that the memory
* allocation performed is done fallibly, i.e. it can return nullptr.
*/
template<typename T, typename... Args>
typename detail::UniqueSelector<T>::SingleObject
MakeUniqueFallible(Args&&... aArgs)
{
return UniquePtr<T>(new (fallible) T(Forward<Args>(aArgs)...));
}
template<typename T>
typename detail::UniqueSelector<T>::UnknownBound
MakeUniqueFallible(decltype(sizeof(int)) aN)
{
typedef typename RemoveExtent<T>::Type ArrayType;
return UniquePtr<T>(new (fallible) ArrayType[aN]());
}
template<typename T, typename... Args>
typename detail::UniqueSelector<T>::KnownBound
MakeUniqueFallible(Args&&... aArgs) = delete;
namespace detail {
template<typename T>
struct FreePolicy
{
void operator()(const void* ptr) {
free(const_cast<void*>(ptr));
}
};
} // namespace detail
template<typename T>
using UniqueFreePtr = UniquePtr<T, detail::FreePolicy<T>>;
} // namespace mozilla
#endif // mozilla_UniquePtrExtensions_h