chromium/third_party/crashpad/crashpad/util/stdlib/aligned_allocator.h

// Copyright 2015 The Crashpad Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef CRASHPAD_UTIL_STDLIB_ALIGNED_ALLOCATOR_H_
#define CRASHPAD_UTIL_STDLIB_ALIGNED_ALLOCATOR_H_

#include <stddef.h>

#include <limits>
#include <memory>
#include <new>
#include <utility>
#include <vector>

namespace crashpad {

//! \brief Allocates memory with the specified alignment constraint.
//!
//! This function wraps `posix_memalign()` or `_aligned_malloc()`. Memory
//! allocated by this function must be released by AlignFree().
void* AlignedAllocate(size_t alignment, size_t size);

//! \brief Frees memory allocated by AlignedAllocate().
//!
//! This function wraps `free()` or `_aligned_free()`.
void AlignedFree(void* pointer);

//! \brief A standard allocator that aligns its allocations as requested,
//!     suitable for use as an allocator in standard containers.
//!
//! This is similar to `std::allocator<T>`, with the addition of an alignment
//! guarantee. \a Alignment must be a power of 2. If \a Alignment is not
//! specified, the default alignment for type \a T is used.
template <class T, size_t Alignment = alignof(T)>
struct AlignedAllocator { … };

template <class T1, class T2, size_t Alignment>
bool operator==(const AlignedAllocator<T1, Alignment>& lhs,
                const AlignedAllocator<T2, Alignment>& rhs) noexcept { … }

template <class T1, class T2, size_t Alignment>
bool operator!=(const AlignedAllocator<T1, Alignment>& lhs,
                const AlignedAllocator<T2, Alignment>& rhs) noexcept { … }

//! \brief A `std::vector` using AlignedAllocator.
//!
//! This is similar to `std::vector<T>`, with the addition of an alignment
//! guarantee. \a Alignment must be a power of 2. If \a Alignment is not
//! specified, the default alignment for type \a T is used.
AlignedVector;

}  // namespace crashpad

#endif  // CRASHPAD_UTIL_STDLIB_ALIGNED_ALLOCATOR_H_