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 // Copyright (c) 2011 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.

 //

 // CityHash Version 1, by Geoff Pike and Jyrki Alakuijala

 //

 // This file provides a few functions for hashing strings. On x86-64

 // hardware in 2011, CityHash64() is faster than other high-quality

 // hash functions, such as Murmur.  This is largely due to higher

 // instruction-level parallelism.  CityHash64() and CityHash128() also perform

 // well on hash-quality tests.

 //

 // CityHash128() is optimized for relatively long strings and returns

 // a 128-bit hash.  For strings more than about 2000 bytes it can be

 // faster than CityHash64().

 //

 // Functions in the CityHash family are not suitable for cryptography.

 //

 // WARNING: This code has not been 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.

 //

 // 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 CITY_HASH_H_

 #define CITY_HASH_H_

 #include "../CityHash.h" // added by moz, specific to nsis project

 #include <stdlib.h>  // for size_t.

 #include <utility>

 typedef unsigned __int8 uint8;

 typedef unsigned __int32 uint32;

 typedef unsigned __int64 uint64;

 typedef std::pair<uint64, uint64> uint128;

 inline uint64 Uint128Low64(const uint128& x) { return x.first; }

 inline uint64 Uint128High64(const uint128& x) { return x.second; }

 // Hash function for a byte array.

 uint64 CityHash64(const char *buf, size_t len);

 // Hash function for a byte array.  For convenience, a 64-bit seed is also

 // hashed into the result.

 uint64 CityHash64WithSeed(const char *buf, size_t len, uint64 seed);

 // Hash function for a byte array.  For convenience, two seeds are also

 // hashed into the result.

 uint64 CityHash64WithSeeds(const char *buf, size_t len,

                            uint64 seed0, uint64 seed1);

 // Hash function for a byte array.

 uint128 CityHash128(const char *s, size_t len);

 // Hash function for a byte array.  For convenience, a 128-bit seed is also

 // hashed into the result.

 uint128 CityHash128WithSeed(const char *s, size_t len, uint128 seed);

 // Hash 128 input bits down to 64 bits of output.

 // This is intended to be a reasonably good hash function.

 inline uint64 Hash128to64(const uint128& x) {

   // Murmur-inspired hashing.

   const uint64 kMul = 0x9ddfea08eb382d69;

   uint64 a = (Uint128Low64(x) ^ Uint128High64(x)) * kMul;

   a ^= (a >> 47);

   uint64 b = (Uint128High64(x) ^ a) * kMul;

   b ^= (b >> 47);

   b *= kMul;

   return b;

 }

 #endif  // CITY_HASH_H_