webrtc/rtc_base/memory/aligned_malloc.h
Karl Wiberg 29e7bee330 Move aligned memory utilities to rtc_base/memory/
This moves them from an API directory (system_wrappers/include/) to a
non-API directory, which is exactly what we want for utilities like
this.

BUG=webrtc:8445

Change-Id: I6dc34fe662f5d87b3b5288d33055345bc6bf91db
Reviewed-on: https://webrtc-review.googlesource.com/21164
Commit-Queue: Karl Wiberg <kwiberg@webrtc.org>
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22567}
2018-03-22 14:13:24 +00:00

57 lines
2 KiB
C++

/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef RTC_BASE_MEMORY_ALIGNED_MALLOC_H_
#define RTC_BASE_MEMORY_ALIGNED_MALLOC_H_
// The functions declared here
// 1) Allocates block of aligned memory.
// 2) Re-calculates a pointer such that it is aligned to a higher or equal
// address.
// Note: alignment must be a power of two. The alignment is in bytes.
#include <stddef.h>
namespace webrtc {
// Returns a pointer to the first boundry of |alignment| bytes following the
// address of |ptr|.
// Note that there is no guarantee that the memory in question is available.
// |ptr| has no requirements other than it can't be NULL.
void* GetRightAlign(const void* ptr, size_t alignment);
// Allocates memory of |size| bytes aligned on an |alignment| boundry.
// The return value is a pointer to the memory. Note that the memory must
// be de-allocated using AlignedFree.
void* AlignedMalloc(size_t size, size_t alignment);
// De-allocates memory created using the AlignedMalloc() API.
void AlignedFree(void* mem_block);
// Templated versions to facilitate usage of aligned malloc without casting
// to and from void*.
template <typename T>
T* GetRightAlign(const T* ptr, size_t alignment) {
return reinterpret_cast<T*>(
GetRightAlign(reinterpret_cast<const void*>(ptr), alignment));
}
template <typename T>
T* AlignedMalloc(size_t size, size_t alignment) {
return reinterpret_cast<T*>(AlignedMalloc(size, alignment));
}
// Deleter for use with unique_ptr. E.g., use as
// std::unique_ptr<Foo, AlignedFreeDeleter> foo;
struct AlignedFreeDeleter {
inline void operator()(void* ptr) const { AlignedFree(ptr); }
};
} // namespace webrtc
#endif // RTC_BASE_MEMORY_ALIGNED_MALLOC_H_