FreeBSD/Linux Kernel Cross Reference
sys/sys/hash.h

     /*      $NetBSD: hash.h,v 1.8 2014/09/05 05:46:15 matt Exp $    */
     
     /*-
      * Copyright (c) 2001 The NetBSD Foundation, Inc.
      * All rights reserved.
      *
      * This code is derived from software contributed to The NetBSD Foundation
      * by Luke Mewburn.
      *
     * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions
     * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     *
     * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     * POSSIBILITY OF SUCH DAMAGE.
     */
    
    #ifndef _SYS_HASH_H_
    #define _SYS_HASH_H_
    
    #include <sys/types.h>
    
    #ifdef __HAVE_MACHINE_HASH_H
    #include <machine/hash.h>
    #endif
    
    #ifndef __HAVE_HASH32_BUF                       /* not overridden by MD hash */
    
    #define HASH32_BUF_INIT 5381
    
    /*
     * uint32_t
     * hash32_buf(const void *bf, size_t len, uint32_t hash)
     *      return a 32 bit hash of the binary buffer buf (size len),
     *      seeded with an initial hash value of hash (usually HASH32_BUF_INIT).
     */
    static __inline uint32_t
    hash32_buf(const void *bf, size_t len, uint32_t hash)
    {
            const uint8_t *s = (const uint8_t *)bf;
    
            while (len-- != 0)                      /* "nemesi": k=257, r=r*257 */
                    hash = hash * 257 + *s++;
            return (hash * 257);
    }
    #endif  /* __HAVE_HASH32_BUF */
    
    
    #ifndef __HAVE_HASH32_STR                       /* not overridden by MD hash */
    
    #define HASH32_STR_INIT 5381
    /*
     * uint32_t
     * hash32_str(const void *bf, uint32_t hash)
     *      return a 32 bit hash of NUL terminated ASCII string buf,
     *      seeded with an initial hash value of hash (usually HASH32_STR_INIT).
     */
    static __inline uint32_t
    hash32_str(const void *bf, uint32_t hash)
    {
            const uint8_t *s = (const uint8_t *)bf;
            uint8_t c;
    
            while ((c = *s++) != 0)
                    hash = hash * 33 + c;           /* "perl": k=33, r=r+r/32 */
            return (hash + (hash >> 5));
    }
    
    /*
     * uint32_t
     * hash32_strn(const void *bf, size_t len, uint32_t hash)
     *      return a 32 bit hash of NUL terminated ASCII string buf up to
     *      a maximum of len bytes,
     *      seeded with an initial hash value of hash (usually HASH32_STR_INIT).
     */
    static __inline uint32_t
    hash32_strn(const void *bf, size_t len, uint32_t hash)
    {
            const uint8_t *s = (const uint8_t *)bf;
            uint8_t c;
    
            while ((c = *s++) != 0 && len-- != 0)
                    hash = hash * 33 + c;           /* "perl": k=33, r=r+r/32 */
            return (hash + (hash >> 5));
    }
   #endif  /* __HAVE_HASH32_STR */
   
   __BEGIN_DECLS
   uint32_t        murmurhash2(const void *, size_t, uint32_t);
   __END_DECLS
   
   #endif  /* !_SYS_HASH_H_ */

Cache object: a3e1affba5d3df21ec1c5e819bc9a886