1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/security/sandbox/chromium/base/containers/hash_tables.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,264 @@
1.4 +// Copyright (c) 2011 The Chromium Authors. All rights reserved.
1.5 +// Use of this source code is governed by a BSD-style license that can be
1.6 +// found in the LICENSE file.
1.7 +//
1.8 +
1.9 +//
1.10 +// Deal with the differences between Microsoft and GNU implemenations
1.11 +// of hash_map. Allows all platforms to use |base::hash_map| and
1.12 +// |base::hash_set|.
1.13 +// eg:
1.14 +// base::hash_map<int> my_map;
1.15 +// base::hash_set<int> my_set;
1.16 +//
1.17 +// NOTE: It is an explicit non-goal of this class to provide a generic hash
1.18 +// function for pointers. If you want to hash a pointers to a particular class,
1.19 +// please define the template specialization elsewhere (for example, in its
1.20 +// header file) and keep it specific to just pointers to that class. This is
1.21 +// because identity hashes are not desirable for all types that might show up
1.22 +// in containers as pointers.
1.23 +
1.24 +#ifndef BASE_CONTAINERS_HASH_TABLES_H_
1.25 +#define BASE_CONTAINERS_HASH_TABLES_H_
1.26 +
1.27 +#include <utility>
1.28 +
1.29 +#include "base/basictypes.h"
1.30 +#include "base/strings/string16.h"
1.31 +#include "build/build_config.h"
1.32 +
1.33 +#if defined(COMPILER_MSVC)
1.34 +#include <hash_map>
1.35 +#include <hash_set>
1.36 +
1.37 +#define BASE_HASH_NAMESPACE stdext
1.38 +
1.39 +#elif defined(COMPILER_GCC)
1.40 +#if defined(OS_ANDROID)
1.41 +#define BASE_HASH_NAMESPACE std
1.42 +#else
1.43 +#define BASE_HASH_NAMESPACE __gnu_cxx
1.44 +#endif
1.45 +
1.46 +// This is a hack to disable the gcc 4.4 warning about hash_map and hash_set
1.47 +// being deprecated. We can get rid of this when we upgrade to VS2008 and we
1.48 +// can use <tr1/unordered_map> and <tr1/unordered_set>.
1.49 +#ifdef __DEPRECATED
1.50 +#define CHROME_OLD__DEPRECATED __DEPRECATED
1.51 +#undef __DEPRECATED
1.52 +#endif
1.53 +
1.54 +#if defined(OS_ANDROID)
1.55 +#include <hash_map>
1.56 +#include <hash_set>
1.57 +#else
1.58 +#include <ext/hash_map>
1.59 +#include <ext/hash_set>
1.60 +#endif
1.61 +
1.62 +#include <string>
1.63 +
1.64 +#ifdef CHROME_OLD__DEPRECATED
1.65 +#define __DEPRECATED CHROME_OLD__DEPRECATED
1.66 +#undef CHROME_OLD__DEPRECATED
1.67 +#endif
1.68 +
1.69 +namespace BASE_HASH_NAMESPACE {
1.70 +
1.71 +#if !defined(OS_ANDROID)
1.72 +// The GNU C++ library provides identity hash functions for many integral types,
1.73 +// but not for |long long|. This hash function will truncate if |size_t| is
1.74 +// narrower than |long long|. This is probably good enough for what we will
1.75 +// use it for.
1.76 +
1.77 +#define DEFINE_TRIVIAL_HASH(integral_type) \
1.78 + template<> \
1.79 + struct hash<integral_type> { \
1.80 + std::size_t operator()(integral_type value) const { \
1.81 + return static_cast<std::size_t>(value); \
1.82 + } \
1.83 + }
1.84 +
1.85 +DEFINE_TRIVIAL_HASH(long long);
1.86 +DEFINE_TRIVIAL_HASH(unsigned long long);
1.87 +
1.88 +#undef DEFINE_TRIVIAL_HASH
1.89 +#endif // !defined(OS_ANDROID)
1.90 +
1.91 +// Implement string hash functions so that strings of various flavors can
1.92 +// be used as keys in STL maps and sets. The hash algorithm comes from the
1.93 +// GNU C++ library, in <tr1/functional>. It is duplicated here because GCC
1.94 +// versions prior to 4.3.2 are unable to compile <tr1/functional> when RTTI
1.95 +// is disabled, as it is in our build.
1.96 +
1.97 +#define DEFINE_STRING_HASH(string_type) \
1.98 + template<> \
1.99 + struct hash<string_type> { \
1.100 + std::size_t operator()(const string_type& s) const { \
1.101 + std::size_t result = 0; \
1.102 + for (string_type::const_iterator i = s.begin(); i != s.end(); ++i) \
1.103 + result = (result * 131) + *i; \
1.104 + return result; \
1.105 + } \
1.106 + }
1.107 +
1.108 +DEFINE_STRING_HASH(std::string);
1.109 +DEFINE_STRING_HASH(string16);
1.110 +
1.111 +#undef DEFINE_STRING_HASH
1.112 +
1.113 +} // namespace BASE_HASH_NAMESPACE
1.114 +
1.115 +#else // COMPILER
1.116 +#error define BASE_HASH_NAMESPACE for your compiler
1.117 +#endif // COMPILER
1.118 +
1.119 +namespace base {
1.120 +using BASE_HASH_NAMESPACE::hash_map;
1.121 +using BASE_HASH_NAMESPACE::hash_multimap;
1.122 +using BASE_HASH_NAMESPACE::hash_multiset;
1.123 +using BASE_HASH_NAMESPACE::hash_set;
1.124 +
1.125 +// Implement hashing for pairs of at-most 32 bit integer values.
1.126 +// When size_t is 32 bits, we turn the 64-bit hash code into 32 bits by using
1.127 +// multiply-add hashing. This algorithm, as described in
1.128 +// Theorem 4.3.3 of the thesis "Über die Komplexität der Multiplikation in
1.129 +// eingeschränkten Branchingprogrammmodellen" by Woelfel, is:
1.130 +//
1.131 +// h32(x32, y32) = (h64(x32, y32) * rand_odd64 + rand16 * 2^16) % 2^64 / 2^32
1.132 +//
1.133 +// Contact danakj@chromium.org for any questions.
1.134 +inline std::size_t HashInts32(uint32 value1, uint32 value2) {
1.135 + uint64 value1_64 = value1;
1.136 + uint64 hash64 = (value1_64 << 32) | value2;
1.137 +
1.138 + if (sizeof(std::size_t) >= sizeof(uint64))
1.139 + return static_cast<std::size_t>(hash64);
1.140 +
1.141 + uint64 odd_random = 481046412LL << 32 | 1025306955LL;
1.142 + uint32 shift_random = 10121U << 16;
1.143 +
1.144 + hash64 = hash64 * odd_random + shift_random;
1.145 + std::size_t high_bits = static_cast<std::size_t>(
1.146 + hash64 >> (sizeof(uint64) - sizeof(std::size_t)));
1.147 + return high_bits;
1.148 +}
1.149 +
1.150 +// Implement hashing for pairs of up-to 64-bit integer values.
1.151 +// We use the compound integer hash method to produce a 64-bit hash code, by
1.152 +// breaking the two 64-bit inputs into 4 32-bit values:
1.153 +// http://opendatastructures.org/versions/edition-0.1d/ods-java/node33.html#SECTION00832000000000000000
1.154 +// Then we reduce our result to 32 bits if required, similar to above.
1.155 +inline std::size_t HashInts64(uint64 value1, uint64 value2) {
1.156 + uint32 short_random1 = 842304669U;
1.157 + uint32 short_random2 = 619063811U;
1.158 + uint32 short_random3 = 937041849U;
1.159 + uint32 short_random4 = 3309708029U;
1.160 +
1.161 + uint32 value1a = static_cast<uint32>(value1 & 0xffffffff);
1.162 + uint32 value1b = static_cast<uint32>((value1 >> 32) & 0xffffffff);
1.163 + uint32 value2a = static_cast<uint32>(value2 & 0xffffffff);
1.164 + uint32 value2b = static_cast<uint32>((value2 >> 32) & 0xffffffff);
1.165 +
1.166 + uint64 product1 = static_cast<uint64>(value1a) * short_random1;
1.167 + uint64 product2 = static_cast<uint64>(value1b) * short_random2;
1.168 + uint64 product3 = static_cast<uint64>(value2a) * short_random3;
1.169 + uint64 product4 = static_cast<uint64>(value2b) * short_random4;
1.170 +
1.171 + uint64 hash64 = product1 + product2 + product3 + product4;
1.172 +
1.173 + if (sizeof(std::size_t) >= sizeof(uint64))
1.174 + return static_cast<std::size_t>(hash64);
1.175 +
1.176 + uint64 odd_random = 1578233944LL << 32 | 194370989LL;
1.177 + uint32 shift_random = 20591U << 16;
1.178 +
1.179 + hash64 = hash64 * odd_random + shift_random;
1.180 + std::size_t high_bits = static_cast<std::size_t>(
1.181 + hash64 >> (sizeof(uint64) - sizeof(std::size_t)));
1.182 + return high_bits;
1.183 +}
1.184 +
1.185 +#define DEFINE_32BIT_PAIR_HASH(Type1, Type2) \
1.186 +inline std::size_t HashPair(Type1 value1, Type2 value2) { \
1.187 + return HashInts32(value1, value2); \
1.188 +}
1.189 +
1.190 +DEFINE_32BIT_PAIR_HASH(int16, int16);
1.191 +DEFINE_32BIT_PAIR_HASH(int16, uint16);
1.192 +DEFINE_32BIT_PAIR_HASH(int16, int32);
1.193 +DEFINE_32BIT_PAIR_HASH(int16, uint32);
1.194 +DEFINE_32BIT_PAIR_HASH(uint16, int16);
1.195 +DEFINE_32BIT_PAIR_HASH(uint16, uint16);
1.196 +DEFINE_32BIT_PAIR_HASH(uint16, int32);
1.197 +DEFINE_32BIT_PAIR_HASH(uint16, uint32);
1.198 +DEFINE_32BIT_PAIR_HASH(int32, int16);
1.199 +DEFINE_32BIT_PAIR_HASH(int32, uint16);
1.200 +DEFINE_32BIT_PAIR_HASH(int32, int32);
1.201 +DEFINE_32BIT_PAIR_HASH(int32, uint32);
1.202 +DEFINE_32BIT_PAIR_HASH(uint32, int16);
1.203 +DEFINE_32BIT_PAIR_HASH(uint32, uint16);
1.204 +DEFINE_32BIT_PAIR_HASH(uint32, int32);
1.205 +DEFINE_32BIT_PAIR_HASH(uint32, uint32);
1.206 +
1.207 +#undef DEFINE_32BIT_PAIR_HASH
1.208 +
1.209 +#define DEFINE_64BIT_PAIR_HASH(Type1, Type2) \
1.210 +inline std::size_t HashPair(Type1 value1, Type2 value2) { \
1.211 + return HashInts64(value1, value2); \
1.212 +}
1.213 +
1.214 +DEFINE_64BIT_PAIR_HASH(int16, int64);
1.215 +DEFINE_64BIT_PAIR_HASH(int16, uint64);
1.216 +DEFINE_64BIT_PAIR_HASH(uint16, int64);
1.217 +DEFINE_64BIT_PAIR_HASH(uint16, uint64);
1.218 +DEFINE_64BIT_PAIR_HASH(int32, int64);
1.219 +DEFINE_64BIT_PAIR_HASH(int32, uint64);
1.220 +DEFINE_64BIT_PAIR_HASH(uint32, int64);
1.221 +DEFINE_64BIT_PAIR_HASH(uint32, uint64);
1.222 +DEFINE_64BIT_PAIR_HASH(int64, int16);
1.223 +DEFINE_64BIT_PAIR_HASH(int64, uint16);
1.224 +DEFINE_64BIT_PAIR_HASH(int64, int32);
1.225 +DEFINE_64BIT_PAIR_HASH(int64, uint32);
1.226 +DEFINE_64BIT_PAIR_HASH(int64, int64);
1.227 +DEFINE_64BIT_PAIR_HASH(int64, uint64);
1.228 +DEFINE_64BIT_PAIR_HASH(uint64, int16);
1.229 +DEFINE_64BIT_PAIR_HASH(uint64, uint16);
1.230 +DEFINE_64BIT_PAIR_HASH(uint64, int32);
1.231 +DEFINE_64BIT_PAIR_HASH(uint64, uint32);
1.232 +DEFINE_64BIT_PAIR_HASH(uint64, int64);
1.233 +DEFINE_64BIT_PAIR_HASH(uint64, uint64);
1.234 +
1.235 +#undef DEFINE_64BIT_PAIR_HASH
1.236 +} // namespace base
1.237 +
1.238 +namespace BASE_HASH_NAMESPACE {
1.239 +
1.240 +// Implement methods for hashing a pair of integers, so they can be used as
1.241 +// keys in STL containers.
1.242 +
1.243 +#if defined(COMPILER_MSVC)
1.244 +
1.245 +template<typename Type1, typename Type2>
1.246 +inline std::size_t hash_value(const std::pair<Type1, Type2>& value) {
1.247 + return base::HashPair(value.first, value.second);
1.248 +}
1.249 +
1.250 +#elif defined(COMPILER_GCC)
1.251 +template<typename Type1, typename Type2>
1.252 +struct hash<std::pair<Type1, Type2> > {
1.253 + std::size_t operator()(std::pair<Type1, Type2> value) const {
1.254 + return base::HashPair(value.first, value.second);
1.255 + }
1.256 +};
1.257 +
1.258 +#else
1.259 +#error define hash<std::pair<Type1, Type2> > for your compiler
1.260 +#endif // COMPILER
1.261 +
1.262 +}
1.263 +
1.264 +#undef DEFINE_PAIR_HASH_FUNCTION_START
1.265 +#undef DEFINE_PAIR_HASH_FUNCTION_END
1.266 +
1.267 +#endif // BASE_CONTAINERS_HASH_TABLES_H_
