Where Online Learning is simpler!

The C and C++ Include Header Files

/usr/include/ntirpc/misc/city.h


$ cat -n /usr/include/ntirpc/misc/city.h

     1	/* city.h - cityhash-c
     2	 * CityHash on C
     3	 * Copyright (c) 2011-2012, Alexander Nusov
     4	 *
     5	 * - original copyright notice -
     6	 * Copyright (c) 2011 Google, Inc.
     7	 *
     8	 * Permission is hereby granted, free of charge, to any person obtaining a copy
     9	 * of this software and associated documentation files (the "Software"), to deal
    10	 * in the Software without restriction, including without limitation the rights
    11	 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    12	 * copies of the Software, and to permit persons to whom the Software is
    13	 * furnished to do so, subject to the following conditions:
    14	 *
    15	 * The above copyright notice and this permission notice shall be included in
    16	 * all copies or substantial portions of the Software.
    17	 *
    18	 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    19	 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    20	 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    21	 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    22	 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    23	 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    24	 * THE SOFTWARE.
    25	 *
    26	 * CityHash, by Geoff Pike and Jyrki Alakuijala
    27	 *
    28	 * This file provides a few functions for hashing strings. On x86-64
    29	 * hardware in 2011, CityHash64() is faster than other high-quality
    30	 * hash functions, such as Murmur.  This is largely due to higher
    31	 * instruction-level parallelism.  CityHash64() and CityHash128() also perform
    32	 * well on hash-quality tests.
    33	 *
    34	 * CityHash128() is optimized for relatively long strings and returns
    35	 * a 128-bit hash.  For strings more than about 2000 bytes it can be
    36	 * faster than CityHash64().
    37	 *
    38	 * Functions in the CityHash family are not suitable for cryptography.
    39	 *
    40	 * WARNING: This code has not been tested on big-endian platforms!
    41	 * It is known to work well on little-endian platforms that have a small penalty
    42	 * for unaligned reads, such as current Intel and AMD moderate-to-high-end CPUs.
    43	 *
    44	 * By the way, for some hash functions, given strings a and b, the hash
    45	 * of a+b is easily derived from the hashes of a and b.  This property
    46	 * doesn't hold for any hash functions in this file.
    47	 */
    48	
    49	#ifndef CITY_HASH_H_
    50	#define CITY_HASH_H_
    51	
    52	#include <stdlib.h>
    53	#include <stdint.h>
    54	
    55	typedef uint8_t uint8;
    56	typedef uint32_t uint32;
    57	typedef uint64_t uint64;
    58	
    59	typedef struct _uint128 uint128;
    60	struct _uint128 {
    61		uint64 first;
    62		uint64 second;
    63	};
    64	
    65	#define Uint128Low64(x) ((x).first)
    66	#define Uint128High64(x) ((x).second)
    67	
    68	/* Hash function for a byte array. */
    69	uint64 CityHash64(const char *buf, size_t len);
    70	
    71	/* Hash function for a byte array.  For convenience, a 64-bit seed is also
    72	 * hashed into the result. */
    73	uint64 CityHash64WithSeed(const char *buf, size_t len, uint64 seed);
    74	
    75	/* Hash function for a byte array.  For convenience, two seeds are also
    76	 * hashed into the result. */
    77	uint64 CityHash64WithSeeds(const char *buf, size_t len, uint64 seed0,
    78				   uint64 seed1);
    79	
    80	/* Hash function for a byte array. */
    81	uint128 CityHash128(const char *s, size_t len);
    82	
    83	/* Hash function for a byte array.  For convenience, a 128-bit seed is also
    84	 * hashed into the result. */
    85	uint128 CityHash128WithSeed(const char *s, size_t len, uint128 seed);
    86	
    87	#endif				/* CITY_HASH_H_ */