700 lines
20 KiB
C
700 lines
20 KiB
C
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/***************************************************************************
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* __________ __ ___.
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* Open \______ \ ____ ____ | | _\_ |__ _______ ___
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* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
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* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
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* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
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* \/ \/ \/ \/ \/
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* $Id$
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*
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* Copyright (C) 2006 Bob Jenkins
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* http://burtleburtle.net/bob/c/lookup3.c
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
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* KIND, either express or implied.
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*
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****************************************************************************/
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/*
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lookup3.c, by Bob Jenkins, May 2006, Public Domain.
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These are functions for producing 32-bit hashes for hash table lookup.
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hashword(), hashlittle(), hashlittle2(), hashbig(), mix(), and final()
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are externally useful functions. Routines to test the hash are included
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if SELF_TEST is defined. You can use this free for any purpose. It's in
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the public domain. It has no warranty.
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You probably want to use hashlittle(). hashlittle() and hashbig()
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hash byte arrays. hashlittle() is is faster than hashbig() on
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little-endian machines. Intel and AMD are little-endian machines.
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On second thought, you probably want hashlittle2(), which is identical to
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hashlittle() except it returns two 32-bit hashes for the price of one.
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You could implement hashbig2() if you wanted but I haven't bothered here.
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If you want to find a hash of, say, exactly 7 integers, do
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a = i1; b = i2; c = i3;
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mix(a,b,c);
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a += i4; b += i5; c += i6;
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mix(a,b,c);
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a += i7;
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final(a,b,c);
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then use c as the hash value. If you have a variable length array of
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4-byte integers to hash, use hashword(). If you have a byte array (like
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a character string), use hashlittle(). If you have several byte arrays, or
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a mix of things, see the comments above hashlittle().
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Why is this so big? I read 12 bytes at a time into 3 4-byte integers,
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then mix those integers. This is fast (you can do a lot more thorough
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mixing with 12*3 instructions on 3 integers than you can with 3 instructions
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on 1 byte), but shoehorning those bytes into integers efficiently is messy.
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*/
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#include "jhash.h"
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/*
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* My best guess at if you are big-endian or little-endian. This may
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* need adjustment.
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*/
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#if defined(ROCKBOX_LITTLE_ENDIAN)
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# define HASH_LITTLE_ENDIAN 1
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# define HASH_BIG_ENDIAN 0
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#elif defined(ROCKBOX_BIG_ENDIAN)
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# define HASH_LITTLE_ENDIAN 0
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# define HASH_BIG_ENDIAN 1
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#else
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# define HASH_LITTLE_ENDIAN 0
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# define HASH_BIG_ENDIAN 0
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#endif
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#define hashsize(n) ((uint32_t)1<<(n))
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#define hashmask(n) (hashsize(n)-1)
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#define rot(x,k) (((x)<<(k)) | ((x)>>(32-(k))))
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/*
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mix -- mix 3 32-bit values reversibly.
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This is reversible, so any information in (a,b,c) before mix() is
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still in (a,b,c) after mix().
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If four pairs of (a,b,c) inputs are run through mix(), or through
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mix() in reverse, there are at least 32 bits of the output that
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are sometimes the same for one pair and different for another pair.
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This was tested for:
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* pairs that differed by one bit, by two bits, in any combination
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of top bits of (a,b,c), or in any combination of bottom bits of
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(a,b,c).
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* "differ" is defined as +, -, ^, or ~^. For + and -, I transformed
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the output delta to a Gray code (a^(a>>1)) so a string of 1's (as
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is commonly produced by subtraction) look like a single 1-bit
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difference.
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* the base values were pseudorandom, all zero but one bit set, or
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all zero plus a counter that starts at zero.
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Some k values for my "a-=c; a^=rot(c,k); c+=b;" arrangement that
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satisfy this are
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4 6 8 16 19 4
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9 15 3 18 27 15
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14 9 3 7 17 3
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Well, "9 15 3 18 27 15" didn't quite get 32 bits diffing
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for "differ" defined as + with a one-bit base and a two-bit delta. I
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used http://burtleburtle.net/bob/hash/avalanche.html to choose
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the operations, constants, and arrangements of the variables.
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This does not achieve avalanche. There are input bits of (a,b,c)
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that fail to affect some output bits of (a,b,c), especially of a. The
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most thoroughly mixed value is c, but it doesn't really even achieve
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avalanche in c.
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This allows some parallelism. Read-after-writes are good at doubling
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the number of bits affected, so the goal of mixing pulls in the opposite
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direction as the goal of parallelism. I did what I could. Rotates
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seem to cost as much as shifts on every machine I could lay my hands
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on, and rotates are much kinder to the top and bottom bits, so I used
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rotates.
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*/
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#define mix(a,b,c) \
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{ \
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a -= c; a ^= rot(c, 4); c += b; \
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b -= a; b ^= rot(a, 6); a += c; \
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c -= b; c ^= rot(b, 8); b += a; \
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a -= c; a ^= rot(c,16); c += b; \
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b -= a; b ^= rot(a,19); a += c; \
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c -= b; c ^= rot(b, 4); b += a; \
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}
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/*
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final -- final mixing of 3 32-bit values (a,b,c) into c
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Pairs of (a,b,c) values differing in only a few bits will usually
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produce values of c that look totally different. This was tested for
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* pairs that differed by one bit, by two bits, in any combination
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of top bits of (a,b,c), or in any combination of bottom bits of
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(a,b,c).
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* "differ" is defined as +, -, ^, or ~^. For + and -, I transformed
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the output delta to a Gray code (a^(a>>1)) so a string of 1's (as
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is commonly produced by subtraction) look like a single 1-bit
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difference.
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* the base values were pseudorandom, all zero but one bit set, or
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all zero plus a counter that starts at zero.
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These constants passed:
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14 11 25 16 4 14 24
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12 14 25 16 4 14 24
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and these came close:
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4 8 15 26 3 22 24
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10 8 15 26 3 22 24
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11 8 15 26 3 22 24
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*/
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#define final(a,b,c) \
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{ \
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c ^= b; c -= rot(b,14); \
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a ^= c; a -= rot(c,11); \
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b ^= a; b -= rot(a,25); \
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c ^= b; c -= rot(b,16); \
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a ^= c; a -= rot(c,4); \
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b ^= a; b -= rot(a,14); \
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c ^= b; c -= rot(b,24); \
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}
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/*
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k: pointer to the key, an array of uint32_t
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length: number of elements in the key
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initval: an initialization value
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returns the 32-bit hash
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*/
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uint32_t hashw(const uint32_t *k, size_t length, uint32_t initval)
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{
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uint32_t a, b, c;
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/* Set up the internal state */
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a = b = c = 0xdeadbeef + (((uint32_t)length)<<2) + initval;
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/* handle most of the key */
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while (length > 3)
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{
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a += k[0];
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b += k[1];
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c += k[2];
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mix(a,b,c);
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length -= 3;
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k += 3;
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}
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/* handle the last 3 uint32_t's */
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switch(length) /* all the case statements fall through */
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{
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case 3:
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c+=k[2];
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case 2:
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b+=k[1];
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case 1:
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a+=k[0];
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final(a,b,c);
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case 0: /* case 0: nothing left to add */
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break;
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}
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/* report the result */
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return c;
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}
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/*
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hashw2() -- same as hashw(), but take two seeds and return two
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32-bit values. pc and pb must both be nonnull, and *pc and *pb must
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both be initialized with seeds. If you pass in (*pb)==0, the output
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(*pc) will be the same as the return value from hashword().
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k: pointer to the key, an array of uint32_t
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length: number of elements in the key
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pc, pb: pointers to primary and secondary initial values, also used to store
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the hash results.
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*/
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void hashw2 (const uint32_t *k, size_t length, uint32_t *pc, uint32_t *pb)
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{
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uint32_t a,b,c;
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/* Set up the internal state */
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a = b = c = 0xdeadbeef + ((uint32_t)(length<<2)) + *pc;
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c += *pb;
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/* handle most of the key */
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while (length > 3)
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{
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a += k[0];
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b += k[1];
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c += k[2];
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mix(a,b,c);
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length -= 3;
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k += 3;
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}
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/* handle the last 3 uint32_t's */
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switch(length) /* all the case statements fall through */
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{
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case 3:
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c+=k[2];
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case 2:
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b+=k[1];
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case 1:
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a+=k[0];
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final(a,b,c);
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case 0: /* case 0: nothing left to add */
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break;
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}
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/* report the result */
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*pc=c; *pb=b;
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}
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/*
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hashs() -- hash a variable-length key into a 32-bit value
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k: pointer to the key, an array of bytes
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length: number of elements in the key
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initval: an initialization value
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returns the 32-bit hash
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Returns a 32-bit value. Every bit of the key affects every bit of
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the return value. Two keys differing by one or two bits will have
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totally different hash values.
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The best hash table sizes are powers of 2. There is no need to do
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mod a prime (mod is sooo slow!). If you need less than 32 bits,
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use a bitmask. For example, if you need only 10 bits, do
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h = (h & hashmask(10));
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In which case, the hash table should have hashsize(10) elements.
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If you are hashing n strings (uint8_t **)k, do it like this:
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for (i=0, h=0; i<n; ++i) h = hashlittle( k[i], len[i], h);
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By Bob Jenkins, 2006. bob_jenkins@burtleburtle.net. You may use this
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code any way you wish, private, educational, or commercial. It's free.
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Use for hash table lookup, or anything where one collision in 2^^32 is
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acceptable. Do NOT use for cryptographic purposes.
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*/
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uint32_t hashs( const void *key, size_t length, uint32_t initval)
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{
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uint32_t a,b,c; /* internal state */
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union { const void *ptr; size_t i; } u;/* needed for Mac Powerbook G4 */
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/* Set up the internal state */
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a = b = c = 0xdeadbeef + ((uint32_t)length) + initval;
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u.ptr = key;
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#if HASH_LITTLE_ENDIAN
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if ((u.i & 0x3) == 0) {
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const uint32_t *k = (const uint32_t *)key; /* read 32-bit chunks */
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/* all but last block: aligned reads and affect 32 bits of (a,b,c) */
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while (length > 12)
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{
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a += k[0];
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b += k[1];
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c += k[2];
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mix(a,b,c);
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length -= 12;
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k += 3;
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}
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/* handle the last (probably partial) block */
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switch(length)
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{
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case 12:
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c += k[2];
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b += k[1];
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a += k[0];
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break;
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case 11:
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c += k[2] & 0xffffff;
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b += k[1];
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a += k[0];
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break;
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case 10:
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c += k[2] & 0xffff;
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b += k[1];
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a += k[0];
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break;
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case 9:
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c += k[2] & 0xff;
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b += k[1];
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a += k[0];
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break;
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case 8:
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b += k[1];
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a += k[0];
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break;
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case 7:
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b += k[1] & 0xffffff;
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a += k[0];
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break;
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case 6:
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b += k[1] & 0xffff;
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a += k[0];
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break;
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case 5:
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b += k[1] & 0xff;
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a += k[0];
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break;
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case 4:
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a += k[0];
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break;
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case 3:
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a += k[0] & 0xffffff;
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break;
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case 2 :
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a += k[0] & 0xffff;
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break;
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case 1:
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a += k[0] & 0xff;
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break;
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case 0:
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return c; /* zero length strings require no mixing */
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}
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} else if ((u.i & 0x1) == 0) {
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const uint16_t *k = (const uint16_t *)key; /* read 16-bit chunks */
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const uint8_t *k8;
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/* all but last block: aligned reads and different mixing */
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|
|
while (length > 12)
|
||
|
|
{
|
||
|
|
a += k[0] + (((uint32_t)k[1])<<16);
|
||
|
|
b += k[2] + (((uint32_t)k[3])<<16);
|
||
|
|
c += k[4] + (((uint32_t)k[5])<<16);
|
||
|
|
mix(a,b,c);
|
||
|
|
length -= 12;
|
||
|
|
k += 6;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* handle the last (probably partial) block */
|
||
|
|
k8 = (const uint8_t *)k;
|
||
|
|
switch(length)
|
||
|
|
{
|
||
|
|
case 12:
|
||
|
|
c += k[4] + (((uint32_t)k[5])<<16);
|
||
|
|
b += k[2] + (((uint32_t)k[3])<<16);
|
||
|
|
a += k[0] + (((uint32_t)k[1])<<16);
|
||
|
|
break;
|
||
|
|
case 11:
|
||
|
|
c += ((uint32_t)k8[10])<<16; /* fall through */
|
||
|
|
case 10:
|
||
|
|
c += k[4];
|
||
|
|
b += k[2] + (((uint32_t)k[3])<<16);
|
||
|
|
a += k[0] + (((uint32_t)k[1])<<16);
|
||
|
|
break;
|
||
|
|
case 9:
|
||
|
|
c += k8[8]; /* fall through */
|
||
|
|
case 8:
|
||
|
|
b += k[2] + (((uint32_t)k[3])<<16);
|
||
|
|
a += k[0] + (((uint32_t)k[1])<<16);
|
||
|
|
break;
|
||
|
|
case 7:
|
||
|
|
b += ((uint32_t)k8[6])<<16; /* fall through */
|
||
|
|
case 6:
|
||
|
|
b += k[2];
|
||
|
|
a += k[0] + (((uint32_t)k[1])<<16);
|
||
|
|
break;
|
||
|
|
case 5:
|
||
|
|
b += k8[4]; /* fall through */
|
||
|
|
case 4:
|
||
|
|
a += k[0] + (((uint32_t)k[1])<<16);
|
||
|
|
break;
|
||
|
|
case 3:
|
||
|
|
a += ((uint32_t)k8[2])<<16; /* fall through */
|
||
|
|
case 2:
|
||
|
|
a += k[0];
|
||
|
|
break;
|
||
|
|
case 1:
|
||
|
|
a += k8[0];
|
||
|
|
break;
|
||
|
|
case 0:
|
||
|
|
return c; /* zero length requires no mixing */
|
||
|
|
}
|
||
|
|
|
||
|
|
} else
|
||
|
|
#endif
|
||
|
|
{ /* need to read the key one byte at a time */
|
||
|
|
const uint8_t *k = (const uint8_t *)key;
|
||
|
|
|
||
|
|
/* all but the last block: affect some 32 bits of (a,b,c) */
|
||
|
|
while (length > 12)
|
||
|
|
{
|
||
|
|
a += k[0];
|
||
|
|
a += ((uint32_t)k[1])<<8;
|
||
|
|
a += ((uint32_t)k[2])<<16;
|
||
|
|
a += ((uint32_t)k[3])<<24;
|
||
|
|
b += k[4];
|
||
|
|
b += ((uint32_t)k[5])<<8;
|
||
|
|
b += ((uint32_t)k[6])<<16;
|
||
|
|
b += ((uint32_t)k[7])<<24;
|
||
|
|
c += k[8];
|
||
|
|
c += ((uint32_t)k[9])<<8;
|
||
|
|
c += ((uint32_t)k[10])<<16;
|
||
|
|
c += ((uint32_t)k[11])<<24;
|
||
|
|
mix(a,b,c);
|
||
|
|
length -= 12;
|
||
|
|
k += 12;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* last block: affect all 32 bits of (c) */
|
||
|
|
switch(length) /* all the case statements fall through */
|
||
|
|
{
|
||
|
|
case 12:
|
||
|
|
c += ((uint32_t)k[11])<<24;
|
||
|
|
case 11:
|
||
|
|
c += ((uint32_t)k[10])<<16;
|
||
|
|
case 10:
|
||
|
|
c += ((uint32_t)k[9])<<8;
|
||
|
|
case 9:
|
||
|
|
c += k[8];
|
||
|
|
case 8:
|
||
|
|
b += ((uint32_t)k[7])<<24;
|
||
|
|
case 7:
|
||
|
|
b += ((uint32_t)k[6])<<16;
|
||
|
|
case 6:
|
||
|
|
b += ((uint32_t)k[5])<<8;
|
||
|
|
case 5:
|
||
|
|
b += k[4];
|
||
|
|
case 4:
|
||
|
|
a += ((uint32_t)k[3])<<24;
|
||
|
|
case 3:
|
||
|
|
a += ((uint32_t)k[2])<<16;
|
||
|
|
case 2:
|
||
|
|
a += ((uint32_t)k[1])<<8;
|
||
|
|
case 1:
|
||
|
|
a +=k [0];
|
||
|
|
break;
|
||
|
|
case 0:
|
||
|
|
return c;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
final(a,b,c);
|
||
|
|
return c;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/*
|
||
|
|
hashs2: return 2 32-bit hash values
|
||
|
|
k: pointer to the key, an array of bytes
|
||
|
|
length: number of elements in the key
|
||
|
|
pc, pb: pointers to primary and secondary initial values, also used to store
|
||
|
|
the hash results.
|
||
|
|
* This is identical to hashlittle(), except it returns two 32-bit hash
|
||
|
|
* values instead of just one. This is good enough for hash table
|
||
|
|
* lookup with 2^^64 buckets, or if you want a second hash if you're not
|
||
|
|
* happy with the first, or if you want a probably-unique 64-bit ID for
|
||
|
|
* the key. *pc is better mixed than *pb, so use *pc first. If you want
|
||
|
|
* a 64-bit value do something like "*pc + (((uint64_t)*pb)<<32)".
|
||
|
|
*/
|
||
|
|
void hashs2(const void *key, size_t length, uint32_t *pc, uint32_t *pb)
|
||
|
|
{
|
||
|
|
uint32_t a, b, c; /* internal state */
|
||
|
|
union { const void *ptr; size_t i; } u; /* needed for Mac Powerbook G4 */
|
||
|
|
|
||
|
|
/* Set up the internal state */
|
||
|
|
a = b = c = 0xdeadbeef + ((uint32_t)length) + *pc;
|
||
|
|
c += *pb;
|
||
|
|
|
||
|
|
u.ptr = key;
|
||
|
|
#if HASH_LITTLE_ENDIAN
|
||
|
|
if (((u.i & 0x3) == 0)) {
|
||
|
|
const uint32_t *k = (const uint32_t *)key; /* read 32-bit chunks */
|
||
|
|
|
||
|
|
/* all but last block: aligned reads and affect 32 bits of (a,b,c) */
|
||
|
|
while (length > 12)
|
||
|
|
{
|
||
|
|
a += k[0];
|
||
|
|
b += k[1];
|
||
|
|
c += k[2];
|
||
|
|
mix(a,b,c);
|
||
|
|
length -= 12;
|
||
|
|
k += 3;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* handle the last (probably partial) block */
|
||
|
|
switch(length)
|
||
|
|
{
|
||
|
|
case 12:
|
||
|
|
c += k[2];
|
||
|
|
b += k[1];
|
||
|
|
a += k[0];
|
||
|
|
break;
|
||
|
|
case 11:
|
||
|
|
c += k[2] & 0xffffff;
|
||
|
|
b += k[1];
|
||
|
|
a += k[0];
|
||
|
|
break;
|
||
|
|
case 10:
|
||
|
|
c += k[2] & 0xffff;
|
||
|
|
b += k[1];
|
||
|
|
a += k[0];
|
||
|
|
break;
|
||
|
|
case 9:
|
||
|
|
c += k[2] & 0xff;
|
||
|
|
b += k[1];
|
||
|
|
a += k[0];
|
||
|
|
break;
|
||
|
|
case 8:
|
||
|
|
b += k[1];
|
||
|
|
a += k[0];
|
||
|
|
break;
|
||
|
|
case 7:
|
||
|
|
b += k[1] & 0xffffff;
|
||
|
|
a += k[0];
|
||
|
|
break;
|
||
|
|
case 6:
|
||
|
|
b += k[1] & 0xffff;
|
||
|
|
a += k[0];
|
||
|
|
break;
|
||
|
|
case 5:
|
||
|
|
b += k[1] & 0xff;
|
||
|
|
a += k[0];
|
||
|
|
break;
|
||
|
|
case 4:
|
||
|
|
a += k[0];
|
||
|
|
break;
|
||
|
|
case 3:
|
||
|
|
a += k[0] & 0xffffff;
|
||
|
|
break;
|
||
|
|
case 2:
|
||
|
|
a += k[0] & 0xffff;
|
||
|
|
break;
|
||
|
|
case 1:
|
||
|
|
a += k[0] & 0xff;
|
||
|
|
break;
|
||
|
|
case 0:
|
||
|
|
*pc=c;
|
||
|
|
*pb=b;
|
||
|
|
return; /* zero length strings require no mixing */
|
||
|
|
}
|
||
|
|
} else if (((u.i & 0x1) == 0)) {
|
||
|
|
const uint16_t *k = (const uint16_t *)key; /* read 16-bit chunks */
|
||
|
|
const uint8_t *k8;
|
||
|
|
|
||
|
|
/* all but last block: aligned reads and different mixing */
|
||
|
|
while (length > 12)
|
||
|
|
{
|
||
|
|
a += k[0] + (((uint32_t)k[1])<<16);
|
||
|
|
b += k[2] + (((uint32_t)k[3])<<16);
|
||
|
|
c += k[4] + (((uint32_t)k[5])<<16);
|
||
|
|
mix(a,b,c);
|
||
|
|
length -= 12;
|
||
|
|
k += 6;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* handle the last (probably partial) block */
|
||
|
|
k8 = (const uint8_t *)k;
|
||
|
|
switch(length)
|
||
|
|
{
|
||
|
|
case 12:
|
||
|
|
c += k[4] + (((uint32_t)k[5])<<16);
|
||
|
|
b += k[2] + (((uint32_t)k[3])<<16);
|
||
|
|
a += k[0] + (((uint32_t)k[1])<<16);
|
||
|
|
break;
|
||
|
|
case 11:
|
||
|
|
c += ((uint32_t)k8[10])<<16; /* fall through */
|
||
|
|
case 10:
|
||
|
|
c += k[4];
|
||
|
|
b += k[2] + (((uint32_t)k[3])<<16);
|
||
|
|
a += k[0] + (((uint32_t)k[1])<<16);
|
||
|
|
break;
|
||
|
|
case 9:
|
||
|
|
c += k8[8]; /* fall through */
|
||
|
|
case 8:
|
||
|
|
b += k[2] + (((uint32_t)k[3])<<16);
|
||
|
|
a += k[0] + (((uint32_t)k[1])<<16);
|
||
|
|
break;
|
||
|
|
case 7:
|
||
|
|
b += ((uint32_t)k8[6])<<16; /* fall through */
|
||
|
|
case 6:
|
||
|
|
b += k[2];
|
||
|
|
a += k[0] + (((uint32_t)k[1])<<16);
|
||
|
|
break;
|
||
|
|
case 5:
|
||
|
|
b += k8[4]; /* fall through */
|
||
|
|
case 4:
|
||
|
|
a += k[0] + (((uint32_t)k[1])<<16);
|
||
|
|
break;
|
||
|
|
case 3:
|
||
|
|
a += ((uint32_t)k8[2])<<16; /* fall through */
|
||
|
|
case 2:
|
||
|
|
a += k[0];
|
||
|
|
break;
|
||
|
|
case 1:
|
||
|
|
a += k8[0];
|
||
|
|
break;
|
||
|
|
case 0:
|
||
|
|
*pc=c;
|
||
|
|
*pb=b;
|
||
|
|
return; /* zero length strings require no mixing */
|
||
|
|
}
|
||
|
|
} else
|
||
|
|
#endif
|
||
|
|
{ /* need to read the key one byte at a time */
|
||
|
|
const uint8_t *k = (const uint8_t *)key;
|
||
|
|
|
||
|
|
/* all but the last block: affect some 32 bits of (a,b,c) */
|
||
|
|
while (length > 12)
|
||
|
|
{
|
||
|
|
a += k[0];
|
||
|
|
a += ((uint32_t)k[1])<<8;
|
||
|
|
a += ((uint32_t)k[2])<<16;
|
||
|
|
a += ((uint32_t)k[3])<<24;
|
||
|
|
b += k[4];
|
||
|
|
b += ((uint32_t)k[5])<<8;
|
||
|
|
b += ((uint32_t)k[6])<<16;
|
||
|
|
b += ((uint32_t)k[7])<<24;
|
||
|
|
c += k[8];
|
||
|
|
c += ((uint32_t)k[9])<<8;
|
||
|
|
c += ((uint32_t)k[10])<<16;
|
||
|
|
c += ((uint32_t)k[11])<<24;
|
||
|
|
mix(a,b,c);
|
||
|
|
length -= 12;
|
||
|
|
k += 12;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* last block: affect all 32 bits of (c) */
|
||
|
|
switch(length) /* all the case statements fall through */
|
||
|
|
{
|
||
|
|
case 12:
|
||
|
|
c += ((uint32_t)k[11]) << 24;
|
||
|
|
case 11:
|
||
|
|
c += ((uint32_t)k[10]) << 16;
|
||
|
|
case 10:
|
||
|
|
c += ((uint32_t)k[9]) << 8;
|
||
|
|
case 9:
|
||
|
|
c += k[8];
|
||
|
|
case 8:
|
||
|
|
b += ((uint32_t)k[7]) << 24;
|
||
|
|
case 7:
|
||
|
|
b += ((uint32_t)k[6]) << 16;
|
||
|
|
case 6:
|
||
|
|
b += ((uint32_t)k[5]) << 8;
|
||
|
|
case 5:
|
||
|
|
b += k[4];
|
||
|
|
case 4:
|
||
|
|
a += ((uint32_t)k[3]) << 24;
|
||
|
|
case 3:
|
||
|
|
a += ((uint32_t)k[2]) << 16;
|
||
|
|
case 2:
|
||
|
|
a += ((uint32_t)k[1]) << 8;
|
||
|
|
case 1:
|
||
|
|
a += k[0];
|
||
|
|
break;
|
||
|
|
case 0:
|
||
|
|
*pc=c;
|
||
|
|
*pb=b;
|
||
|
|
return; /* zero length strings require no mixing */
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
final(a,b,c);
|
||
|
|
*pc=c;
|
||
|
|
*pb=b;
|
||
|
|
}
|