diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
commit | 36d22d82aa202bb199967e9512281e9a53db42c9 (patch) | |
tree | 105e8c98ddea1c1e4784a60a5a6410fa416be2de /security/sandbox/chromium/base/hash/hash.h | |
parent | Initial commit. (diff) | |
download | firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip |
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'security/sandbox/chromium/base/hash/hash.h')
-rw-r--r-- | security/sandbox/chromium/base/hash/hash.h | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/security/sandbox/chromium/base/hash/hash.h b/security/sandbox/chromium/base/hash/hash.h new file mode 100644 index 0000000000..f55ae45b38 --- /dev/null +++ b/security/sandbox/chromium/base/hash/hash.h @@ -0,0 +1,86 @@ +// Copyright (c) 2011 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_HASH_HASH_H_ +#define BASE_HASH_HASH_H_ + +#include <stddef.h> +#include <stdint.h> + +#include <limits> +#include <string> +#include <utility> + +#include "base/base_export.h" +#include "base/containers/span.h" +#include "base/logging.h" +#include "base/strings/string16.h" +#include "base/strings/string_piece.h" + +namespace base { + +// WARNING: This hash functions should not be used for any cryptographic +// purpose. + +// Deprecated: Computes a hash of a memory buffer, use FastHash() instead. +// If you need to persist a change on disk or between computers, use +// PersistentHash(). +// TODO(https://crbug.com/1025358): Migrate client code to new hash function. +BASE_EXPORT uint32_t Hash(const void* data, size_t length); +BASE_EXPORT uint32_t Hash(const std::string& str); +BASE_EXPORT uint32_t Hash(const string16& str); + +// Really *fast* and high quality hash. +// Recommended hash function for general use, we pick the best performant +// hash for each build target. +// It is prone to be updated whenever a newer/faster hash function is +// publicly available. +// May changed without warning, do not expect stability of outputs. +BASE_EXPORT size_t FastHash(base::span<const uint8_t> data); +inline size_t FastHash(StringPiece str) { + return FastHash(as_bytes(make_span(str))); +} + +// Computes a hash of a memory buffer. This hash function must not change so +// that code can use the hashed values for persistent storage purposes or +// sending across the network. If a new persistent hash function is desired, a +// new version will have to be added in addition. +// +// WARNING: This hash function should not be used for any cryptographic purpose. +BASE_EXPORT uint32_t PersistentHash(base::span<const uint8_t> data); +BASE_EXPORT uint32_t PersistentHash(const void* data, size_t length); +BASE_EXPORT uint32_t PersistentHash(const std::string& str); + +// Hash pairs of 32-bit or 64-bit numbers. +BASE_EXPORT size_t HashInts32(uint32_t value1, uint32_t value2); +BASE_EXPORT size_t HashInts64(uint64_t value1, uint64_t value2); + +template <typename T1, typename T2> +inline size_t HashInts(T1 value1, T2 value2) { + // This condition is expected to be compile-time evaluated and optimised away + // in release builds. + if (sizeof(T1) > sizeof(uint32_t) || (sizeof(T2) > sizeof(uint32_t))) + return HashInts64(value1, value2); + + return HashInts32(static_cast<uint32_t>(value1), + static_cast<uint32_t>(value2)); +} + +// A templated hasher for pairs of integer types. Example: +// +// using MyPair = std::pair<int32_t, int32_t>; +// std::unordered_set<MyPair, base::IntPairHash<MyPair>> set; +template <typename T> +struct IntPairHash; + +template <typename Type1, typename Type2> +struct IntPairHash<std::pair<Type1, Type2>> { + size_t operator()(std::pair<Type1, Type2> value) const { + return HashInts(value.first, value.second); + } +}; + +} // namespace base + +#endif // BASE_HASH_HASH_H_ |