31 lines
638 B
C
31 lines
638 B
C
/* VTreeFS - sdbm.c - sdbm hash function */
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/*
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* sdbm - ndbm work-alike hashed database library
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* based on Per-Aake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
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* author: oz@nexus.yorku.ca
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* status: public domain. keep it that way.
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*
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* hashing routine
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*/
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#include "inc.h"
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/*
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* polynomial conversion ignoring overflows
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* [this seems to work remarkably well, in fact better
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* than the ndbm hash function. Replace at your own risk]
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* use: 65599 nice.
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* 65587 even better.
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*/
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long
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sdbm_hash(const char *str, int len)
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{
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unsigned long n = 0;
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while (len--)
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n = *str++ + (n << 6) + (n << 16) - n;
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return n;
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}
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