mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-12-05 22:12:21 +00:00
291 lines
10 KiB
C++
291 lines
10 KiB
C++
// Copyright (c) 2014 Google, Inc.
|
|
//
|
|
// Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
// of this software and associated documentation files (the "Software"), to deal
|
|
// in the Software without restriction, including without limitation the rights
|
|
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
// copies of the Software, and to permit persons to whom the Software is
|
|
// furnished to do so, subject to the following conditions:
|
|
//
|
|
// The above copyright notice and this permission notice shall be included in
|
|
// all copies or substantial portions of the Software.
|
|
//
|
|
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
// THE SOFTWARE.
|
|
//
|
|
// FarmHash, by Geoff Pike
|
|
|
|
//
|
|
// http://code.google.com/p/farmhash/
|
|
//
|
|
// This file provides a few functions for hashing strings and other
|
|
// data. All of them are high-quality functions in the sense that
|
|
// they do well on standard tests such as Austin Appleby's SMHasher.
|
|
// They're also fast. FarmHash is the successor to CityHash.
|
|
//
|
|
// Functions in the FarmHash family are not suitable for cryptography.
|
|
//
|
|
// WARNING: This code has been only lightly tested on big-endian platforms!
|
|
// It is known to work well on little-endian platforms that have a small penalty
|
|
// for unaligned reads, such as current Intel and AMD moderate-to-high-end CPUs.
|
|
// It should work on all 32-bit and 64-bit platforms that allow unaligned reads;
|
|
// bug reports are welcome.
|
|
//
|
|
// By the way, for some hash functions, given strings a and b, the hash
|
|
// of a+b is easily derived from the hashes of a and b. This property
|
|
// doesn't hold for any hash functions in this file.
|
|
|
|
#ifndef FARM_HASH_H_
|
|
#define FARM_HASH_H_
|
|
|
|
#include <assert.h>
|
|
#include <stdint.h>
|
|
#include <stdlib.h>
|
|
#include <string.h> // for memcpy and memset
|
|
#include <utility>
|
|
|
|
#ifndef NAMESPACE_FOR_HASH_FUNCTIONS
|
|
#define NAMESPACE_FOR_HASH_FUNCTIONS farmhash
|
|
#endif
|
|
|
|
namespace NAMESPACE_FOR_HASH_FUNCTIONS {
|
|
|
|
#if defined(FARMHASH_UINT128_T_DEFINED)
|
|
inline uint64_t Uint128Low64(const uint128_t x) {
|
|
return static_cast<uint64_t>(x);
|
|
}
|
|
inline uint64_t Uint128High64(const uint128_t x) {
|
|
return static_cast<uint64_t>(x >> 64);
|
|
}
|
|
inline uint128_t Uint128(uint64_t lo, uint64_t hi) {
|
|
return lo + (((uint128_t)hi) << 64);
|
|
}
|
|
#else
|
|
typedef std::pair<uint64_t, uint64_t> uint128_t;
|
|
inline uint64_t Uint128Low64(const uint128_t x) { return x.first; }
|
|
inline uint64_t Uint128High64(const uint128_t x) { return x.second; }
|
|
inline uint128_t Uint128(uint64_t lo, uint64_t hi) { return uint128_t(lo, hi); }
|
|
#endif
|
|
|
|
|
|
// BASIC STRING HASHING
|
|
|
|
// Hash function for a byte array.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
size_t Hash(const char* s, size_t len);
|
|
|
|
// Hash function for a byte array. Most useful in 32-bit binaries.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
uint32_t Hash32(const char* s, size_t len);
|
|
|
|
// Hash function for a byte array. For convenience, a 32-bit seed is also
|
|
// hashed into the result.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
uint32_t Hash32WithSeed(const char* s, size_t len, uint32_t seed);
|
|
|
|
// Hash 128 input bits down to 64 bits of output.
|
|
// Hash function for a byte array.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
uint64_t Hash64(const char* s, size_t len);
|
|
|
|
// Hash function for a byte array. For convenience, a 64-bit seed is also
|
|
// hashed into the result.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
uint64_t Hash64WithSeed(const char* s, size_t len, uint64_t seed);
|
|
|
|
// Hash function for a byte array. For convenience, two seeds are also
|
|
// hashed into the result.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
uint64_t Hash64WithSeeds(const char* s, size_t len,
|
|
uint64_t seed0, uint64_t seed1);
|
|
|
|
// Hash function for a byte array.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
uint128_t Hash128(const char* s, size_t len);
|
|
|
|
// Hash function for a byte array. For convenience, a 128-bit seed is also
|
|
// hashed into the result.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
uint128_t Hash128WithSeed(const char* s, size_t len, uint128_t seed);
|
|
|
|
// BASIC NON-STRING HASHING
|
|
|
|
// This is intended to be a reasonably good hash function.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
inline uint64_t Hash128to64(uint128_t x) {
|
|
// Murmur-inspired hashing.
|
|
const uint64_t kMul = 0x9ddfea08eb382d69ULL;
|
|
uint64_t a = (Uint128Low64(x) ^ Uint128High64(x)) * kMul;
|
|
a ^= (a >> 47);
|
|
uint64_t b = (Uint128High64(x) ^ a) * kMul;
|
|
b ^= (b >> 47);
|
|
b *= kMul;
|
|
return b;
|
|
}
|
|
|
|
// FINGERPRINTING (i.e., good, portable, forever-fixed hash functions)
|
|
|
|
// Fingerprint function for a byte array. Most useful in 32-bit binaries.
|
|
uint32_t Fingerprint32(const char* s, size_t len);
|
|
|
|
// Fingerprint function for a byte array.
|
|
uint64_t Fingerprint64(const char* s, size_t len);
|
|
|
|
// Fingerprint function for a byte array.
|
|
uint128_t Fingerprint128(const char* s, size_t len);
|
|
|
|
// This is intended to be a good fingerprinting primitive.
|
|
// See below for more overloads.
|
|
inline uint64_t Fingerprint(uint128_t x) {
|
|
// Murmur-inspired hashing.
|
|
const uint64_t kMul = 0x9ddfea08eb382d69ULL;
|
|
uint64_t a = (Uint128Low64(x) ^ Uint128High64(x)) * kMul;
|
|
a ^= (a >> 47);
|
|
uint64_t b = (Uint128High64(x) ^ a) * kMul;
|
|
b ^= (b >> 44);
|
|
b *= kMul;
|
|
b ^= (b >> 41);
|
|
b *= kMul;
|
|
return b;
|
|
}
|
|
|
|
// This is intended to be a good fingerprinting primitive.
|
|
inline uint64_t Fingerprint(uint64_t x) {
|
|
// Murmur-inspired hashing.
|
|
const uint64_t kMul = 0x9ddfea08eb382d69ULL;
|
|
uint64_t b = x * kMul;
|
|
b ^= (b >> 44);
|
|
b *= kMul;
|
|
b ^= (b >> 41);
|
|
b *= kMul;
|
|
return b;
|
|
}
|
|
|
|
#ifndef FARMHASH_NO_CXX_STRING
|
|
|
|
// Convenience functions to hash or fingerprint C++ strings.
|
|
// These require that Str::data() return a pointer to the first char
|
|
// (as a const char*) and that Str::length() return the string's length;
|
|
// they work with std::string, for example.
|
|
|
|
// Hash function for a byte array.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
template <typename Str>
|
|
inline size_t Hash(const Str& s) {
|
|
assert(sizeof(s[0]) == 1);
|
|
return Hash(s.data(), s.length());
|
|
}
|
|
|
|
// Hash function for a byte array. Most useful in 32-bit binaries.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
template <typename Str>
|
|
inline uint32_t Hash32(const Str& s) {
|
|
assert(sizeof(s[0]) == 1);
|
|
return Hash32(s.data(), s.length());
|
|
}
|
|
|
|
// Hash function for a byte array. For convenience, a 32-bit seed is also
|
|
// hashed into the result.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
template <typename Str>
|
|
inline uint32_t Hash32WithSeed(const Str& s, uint32_t seed) {
|
|
assert(sizeof(s[0]) == 1);
|
|
return Hash32WithSeed(s.data(), s.length(), seed);
|
|
}
|
|
|
|
// Hash 128 input bits down to 64 bits of output.
|
|
// Hash function for a byte array.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
template <typename Str>
|
|
inline uint64_t Hash64(const Str& s) {
|
|
assert(sizeof(s[0]) == 1);
|
|
return Hash64(s.data(), s.length());
|
|
}
|
|
|
|
// Hash function for a byte array. For convenience, a 64-bit seed is also
|
|
// hashed into the result.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
template <typename Str>
|
|
inline uint64_t Hash64WithSeed(const Str& s, uint64_t seed) {
|
|
assert(sizeof(s[0]) == 1);
|
|
return Hash64WithSeed(s.data(), s.length(), seed);
|
|
}
|
|
|
|
// Hash function for a byte array. For convenience, two seeds are also
|
|
// hashed into the result.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
template <typename Str>
|
|
inline uint64_t Hash64WithSeeds(const Str& s, uint64_t seed0, uint64_t seed1) {
|
|
assert(sizeof(s[0]) == 1);
|
|
return Hash64WithSeeds(s.data(), s.length(), seed0, seed1);
|
|
}
|
|
|
|
// Hash function for a byte array.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
template <typename Str>
|
|
inline uint128_t Hash128(const Str& s) {
|
|
assert(sizeof(s[0]) == 1);
|
|
return Hash128(s.data(), s.length());
|
|
}
|
|
|
|
// Hash function for a byte array. For convenience, a 128-bit seed is also
|
|
// hashed into the result.
|
|
// May change from time to time, may differ on different platforms, may differ
|
|
// depending on NDEBUG.
|
|
template <typename Str>
|
|
inline uint128_t Hash128WithSeed(const Str& s, uint128_t seed) {
|
|
assert(sizeof(s[0]) == 1);
|
|
return Hash128(s.data(), s.length(), seed);
|
|
}
|
|
|
|
// FINGERPRINTING (i.e., good, portable, forever-fixed hash functions)
|
|
|
|
// Fingerprint function for a byte array. Most useful in 32-bit binaries.
|
|
template <typename Str>
|
|
inline uint32_t Fingerprint32(const Str& s) {
|
|
assert(sizeof(s[0]) == 1);
|
|
return Fingerprint32(s.data(), s.length());
|
|
}
|
|
|
|
// Fingerprint 128 input bits down to 64 bits of output.
|
|
// Fingerprint function for a byte array.
|
|
template <typename Str>
|
|
inline uint64_t Fingerprint64(const Str& s) {
|
|
assert(sizeof(s[0]) == 1);
|
|
return Fingerprint64(s.data(), s.length());
|
|
}
|
|
|
|
// Fingerprint function for a byte array.
|
|
template <typename Str>
|
|
inline uint128_t Fingerprint128(const Str& s) {
|
|
assert(sizeof(s[0]) == 1);
|
|
return Fingerprint128(s.data(), s.length());
|
|
}
|
|
|
|
#endif
|
|
|
|
} // namespace NAMESPACE_FOR_HASH_FUNCTIONS
|
|
|
|
#endif // FARM_HASH_H_
|