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annotate cdb_hash.c @ 13:0a35d8de4296

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author Henry S. Thompson <ht@inf.ed.ac.uk>
date Fri, 07 Feb 2025 14:43:27 +0000
parents 2cb46628feec
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
0
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
parents:
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1 /* Public domain. */
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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2
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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3 #include "cdb.h"
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
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4
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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5 uint32 cdb_hashadd(uint32 h,unsigned char c)
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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6 {
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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7 h += (h << 5);
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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8 return h ^ c;
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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9 }
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
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10
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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11 uint32 cdb_hash(char *buf,unsigned int len)
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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12 {
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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13 uint32 h;
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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14
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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15 h = CDB_HASHSTART;
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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16 while (len) {
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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17 h = cdb_hashadd(h,*buf++);
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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18 --len;
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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19 }
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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20 return h;
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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21 }