diff options
Diffstat (limited to 'third_party/base/allocator/partition_allocator/partition_cookie.h')
-rw-r--r-- | third_party/base/allocator/partition_allocator/partition_cookie.h | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/third_party/base/allocator/partition_allocator/partition_cookie.h b/third_party/base/allocator/partition_allocator/partition_cookie.h new file mode 100644 index 0000000000..7cf4e84e05 --- /dev/null +++ b/third_party/base/allocator/partition_allocator/partition_cookie.h @@ -0,0 +1,72 @@ +// Copyright (c) 2018 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 THIRD_PARTY_BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_COOKIE_H_ +#define THIRD_PARTY_BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_COOKIE_H_ + +#include "third_party/base/compiler_specific.h" +#include "third_party/base/logging.h" + +namespace pdfium { +namespace base { +namespace internal { + +#if DCHECK_IS_ON() +// Handles alignment up to XMM instructions on Intel. +static constexpr size_t kCookieSize = 16; + +static constexpr unsigned char kCookieValue[kCookieSize] = { + 0xDE, 0xAD, 0xBE, 0xEF, 0xCA, 0xFE, 0xD0, 0x0D, + 0x13, 0x37, 0xF0, 0x05, 0xBA, 0x11, 0xAB, 0x1E}; +#endif + +ALWAYS_INLINE void PartitionCookieCheckValue(void* ptr) { +#if DCHECK_IS_ON() + unsigned char* cookie_ptr = reinterpret_cast<unsigned char*>(ptr); + for (size_t i = 0; i < kCookieSize; ++i, ++cookie_ptr) + DCHECK(*cookie_ptr == kCookieValue[i]); +#endif +} + +ALWAYS_INLINE size_t PartitionCookieSizeAdjustAdd(size_t size) { +#if DCHECK_IS_ON() + // Add space for cookies, checking for integer overflow. TODO(palmer): + // Investigate the performance and code size implications of using + // CheckedNumeric throughout PA. + DCHECK(size + (2 * kCookieSize) > size); + size += 2 * kCookieSize; +#endif + return size; +} + +ALWAYS_INLINE void* PartitionCookieFreePointerAdjust(void* ptr) { +#if DCHECK_IS_ON() + // The value given to the application is actually just after the cookie. + ptr = static_cast<char*>(ptr) - kCookieSize; +#endif + return ptr; +} + +ALWAYS_INLINE size_t PartitionCookieSizeAdjustSubtract(size_t size) { +#if DCHECK_IS_ON() + // Remove space for cookies. + DCHECK(size >= 2 * kCookieSize); + size -= 2 * kCookieSize; +#endif + return size; +} + +ALWAYS_INLINE void PartitionCookieWriteValue(void* ptr) { +#if DCHECK_IS_ON() + unsigned char* cookie_ptr = reinterpret_cast<unsigned char*>(ptr); + for (size_t i = 0; i < kCookieSize; ++i, ++cookie_ptr) + *cookie_ptr = kCookieValue[i]; +#endif +} + +} // namespace internal +} // namespace base +} // namespace pdfium + +#endif // THIRD_PARTY_BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_COOKIE_H_ |