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Diffstat (limited to 'security/sandbox/chromium/base/containers/hash_tables.h')
| -rw-r--r-- | security/sandbox/chromium/base/containers/hash_tables.h | 281 |
1 files changed, 0 insertions, 281 deletions
diff --git a/security/sandbox/chromium/base/containers/hash_tables.h b/security/sandbox/chromium/base/containers/hash_tables.h deleted file mode 100644 index c421dddf3..000000000 --- a/security/sandbox/chromium/base/containers/hash_tables.h +++ /dev/null @@ -1,281 +0,0 @@ -// 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. -// - -// -// Deal with the differences between Microsoft and GNU implemenations -// of hash_map. Allows all platforms to use |base::hash_map| and -// |base::hash_set|. -// eg: -// base::hash_map<int> my_map; -// base::hash_set<int> my_set; -// -// NOTE: It is an explicit non-goal of this class to provide a generic hash -// function for pointers. If you want to hash a pointers to a particular class, -// please define the template specialization elsewhere (for example, in its -// header file) and keep it specific to just pointers to that class. This is -// because identity hashes are not desirable for all types that might show up -// in containers as pointers. - -#ifndef BASE_CONTAINERS_HASH_TABLES_H_ -#define BASE_CONTAINERS_HASH_TABLES_H_ - -#include <stddef.h> -#include <stdint.h> - -#include <utility> - -#include "base/strings/string16.h" -#include "build/build_config.h" - -#if defined(COMPILER_MSVC) -#include <unordered_map> -#include <unordered_set> - -#define BASE_HASH_NAMESPACE std - -#elif defined(COMPILER_GCC) - -#define BASE_HASH_NAMESPACE base_hash - -// This is a hack to disable the gcc 4.4 warning about hash_map and hash_set -// being deprecated. We can get rid of this when we upgrade to VS2008 and we -// can use <tr1/unordered_map> and <tr1/unordered_set>. -#ifdef __DEPRECATED -#define CHROME_OLD__DEPRECATED __DEPRECATED -#undef __DEPRECATED -#endif - -#include <ext/hash_map> -#include <ext/hash_set> -#define BASE_HASH_IMPL_NAMESPACE __gnu_cxx - -#include <string> - -#ifdef CHROME_OLD__DEPRECATED -#define __DEPRECATED CHROME_OLD__DEPRECATED -#undef CHROME_OLD__DEPRECATED -#endif - -namespace BASE_HASH_NAMESPACE { - -// The pre-standard hash behaves like C++11's std::hash, except around pointers. -// const char* is specialized to hash the C string and hash functions for -// general T* are missing. Define a BASE_HASH_NAMESPACE::hash which aligns with -// the C++11 behavior. - -template<typename T> -struct hash { - std::size_t operator()(const T& value) const { - return BASE_HASH_IMPL_NAMESPACE::hash<T>()(value); - } -}; - -template<typename T> -struct hash<T*> { - std::size_t operator()(T* value) const { - return BASE_HASH_IMPL_NAMESPACE::hash<uintptr_t>()( - reinterpret_cast<uintptr_t>(value)); - } -}; - -// The GNU C++ library provides identity hash functions for many integral types, -// but not for |long long|. This hash function will truncate if |size_t| is -// narrower than |long long|. This is probably good enough for what we will -// use it for. - -#define DEFINE_TRIVIAL_HASH(integral_type) \ - template<> \ - struct hash<integral_type> { \ - std::size_t operator()(integral_type value) const { \ - return static_cast<std::size_t>(value); \ - } \ - } - -DEFINE_TRIVIAL_HASH(long long); -DEFINE_TRIVIAL_HASH(unsigned long long); - -#undef DEFINE_TRIVIAL_HASH - -// Implement string hash functions so that strings of various flavors can -// be used as keys in STL maps and sets. The hash algorithm comes from the -// GNU C++ library, in <tr1/functional>. It is duplicated here because GCC -// versions prior to 4.3.2 are unable to compile <tr1/functional> when RTTI -// is disabled, as it is in our build. - -#define DEFINE_STRING_HASH(string_type) \ - template<> \ - struct hash<string_type> { \ - std::size_t operator()(const string_type& s) const { \ - std::size_t result = 0; \ - for (string_type::const_iterator i = s.begin(); i != s.end(); ++i) \ - result = (result * 131) + *i; \ - return result; \ - } \ - } - -DEFINE_STRING_HASH(std::string); -DEFINE_STRING_HASH(base::string16); - -#undef DEFINE_STRING_HASH - -} // namespace BASE_HASH_NAMESPACE - -#else // COMPILER -#error define BASE_HASH_NAMESPACE for your compiler -#endif // COMPILER - -namespace base { - -// On MSVC, use the C++11 containers. -#if defined(COMPILER_MSVC) - -template<class Key, class T, - class Hash = std::hash<Key>, - class Pred = std::equal_to<Key>, - class Alloc = std::allocator<std::pair<const Key, T>>> -using hash_map = std::unordered_map<Key, T, Hash, Pred, Alloc>; - -template<class Key, class T, - class Hash = std::hash<Key>, - class Pred = std::equal_to<Key>, - class Alloc = std::allocator<std::pair<const Key, T>>> -using hash_multimap = std::unordered_multimap<Key, T, Hash, Pred, Alloc>; - -template<class Key, - class Hash = std::hash<Key>, - class Pred = std::equal_to<Key>, - class Alloc = std::allocator<Key>> -using hash_multiset = std::unordered_multiset<Key, Hash, Pred, Alloc>; - -template<class Key, - class Hash = std::hash<Key>, - class Pred = std::equal_to<Key>, - class Alloc = std::allocator<Key>> -using hash_set = std::unordered_set<Key, Hash, Pred, Alloc>; - -#else // !COMPILER_MSVC - -// Otherwise, use the pre-standard ones, but override the default hash to match -// C++11. -template<class Key, class T, - class Hash = BASE_HASH_NAMESPACE::hash<Key>, - class Pred = std::equal_to<Key>, - class Alloc = std::allocator<std::pair<const Key, T>>> -using hash_map = BASE_HASH_IMPL_NAMESPACE::hash_map<Key, T, Hash, Pred, Alloc>; - -template<class Key, class T, - class Hash = BASE_HASH_NAMESPACE::hash<Key>, - class Pred = std::equal_to<Key>, - class Alloc = std::allocator<std::pair<const Key, T>>> -using hash_multimap = - BASE_HASH_IMPL_NAMESPACE::hash_multimap<Key, T, Hash, Pred, Alloc>; - -template<class Key, - class Hash = BASE_HASH_NAMESPACE::hash<Key>, - class Pred = std::equal_to<Key>, - class Alloc = std::allocator<Key>> -using hash_multiset = - BASE_HASH_IMPL_NAMESPACE::hash_multiset<Key, Hash, Pred, Alloc>; - -template<class Key, - class Hash = BASE_HASH_NAMESPACE::hash<Key>, - class Pred = std::equal_to<Key>, - class Alloc = std::allocator<Key>> -using hash_set = BASE_HASH_IMPL_NAMESPACE::hash_set<Key, Hash, Pred, Alloc>; - -#undef BASE_HASH_IMPL_NAMESPACE - -#endif // COMPILER_MSVC - -// Implement hashing for pairs of at-most 32 bit integer values. -// When size_t is 32 bits, we turn the 64-bit hash code into 32 bits by using -// multiply-add hashing. This algorithm, as described in -// Theorem 4.3.3 of the thesis "Über die Komplexität der Multiplikation in -// eingeschränkten Branchingprogrammmodellen" by Woelfel, is: -// -// h32(x32, y32) = (h64(x32, y32) * rand_odd64 + rand16 * 2^16) % 2^64 / 2^32 -// -// Contact danakj@chromium.org for any questions. -inline std::size_t HashInts32(uint32_t value1, uint32_t value2) { - uint64_t value1_64 = value1; - uint64_t hash64 = (value1_64 << 32) | value2; - - if (sizeof(std::size_t) >= sizeof(uint64_t)) - return static_cast<std::size_t>(hash64); - - uint64_t odd_random = 481046412LL << 32 | 1025306955LL; - uint32_t shift_random = 10121U << 16; - - hash64 = hash64 * odd_random + shift_random; - std::size_t high_bits = static_cast<std::size_t>( - hash64 >> (8 * (sizeof(uint64_t) - sizeof(std::size_t)))); - return high_bits; -} - -// Implement hashing for pairs of up-to 64-bit integer values. -// We use the compound integer hash method to produce a 64-bit hash code, by -// breaking the two 64-bit inputs into 4 32-bit values: -// http://opendatastructures.org/versions/edition-0.1d/ods-java/node33.html#SECTION00832000000000000000 -// Then we reduce our result to 32 bits if required, similar to above. -inline std::size_t HashInts64(uint64_t value1, uint64_t value2) { - uint32_t short_random1 = 842304669U; - uint32_t short_random2 = 619063811U; - uint32_t short_random3 = 937041849U; - uint32_t short_random4 = 3309708029U; - - uint32_t value1a = static_cast<uint32_t>(value1 & 0xffffffff); - uint32_t value1b = static_cast<uint32_t>((value1 >> 32) & 0xffffffff); - uint32_t value2a = static_cast<uint32_t>(value2 & 0xffffffff); - uint32_t value2b = static_cast<uint32_t>((value2 >> 32) & 0xffffffff); - - uint64_t product1 = static_cast<uint64_t>(value1a) * short_random1; - uint64_t product2 = static_cast<uint64_t>(value1b) * short_random2; - uint64_t product3 = static_cast<uint64_t>(value2a) * short_random3; - uint64_t product4 = static_cast<uint64_t>(value2b) * short_random4; - - uint64_t hash64 = product1 + product2 + product3 + product4; - - if (sizeof(std::size_t) >= sizeof(uint64_t)) - return static_cast<std::size_t>(hash64); - - uint64_t odd_random = 1578233944LL << 32 | 194370989LL; - uint32_t shift_random = 20591U << 16; - - hash64 = hash64 * odd_random + shift_random; - std::size_t high_bits = static_cast<std::size_t>( - hash64 >> (8 * (sizeof(uint64_t) - sizeof(std::size_t)))); - return high_bits; -} - -template<typename T1, typename T2> -inline std::size_t HashPair(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(value1, value2); -} - -} // namespace base - -namespace BASE_HASH_NAMESPACE { - -// Implement methods for hashing a pair of integers, so they can be used as -// keys in STL containers. - -template<typename Type1, typename Type2> -struct hash<std::pair<Type1, Type2> > { - std::size_t operator()(std::pair<Type1, Type2> value) const { - return base::HashPair(value.first, value.second); - } -}; - -} // namespace BASE_HASH_NAMESPACE - -#undef DEFINE_PAIR_HASH_FUNCTION_START -#undef DEFINE_PAIR_HASH_FUNCTION_END - -#endif // BASE_CONTAINERS_HASH_TABLES_H_ |