Mercurial > hg > cdb

annotate cdb_hash.c @ 16:70f4df5a7283

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add cdb_write, log basic mmap outcomes
author Henry S. Thompson <ht@inf.ed.ac.uk>
date Thu, 27 Feb 2025 18:26:29 +0000
parents 2cb46628feec
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
Henry S. Thompson <ht@inf.ed.ac.uk>
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1 /* Public domain. */
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
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2
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3 #include "cdb.h"
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4
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
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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,
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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;
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9 }
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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 {
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13 uint32 h;
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14
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
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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,
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17 h = cdb_hashadd(h,*buf++);
2cb46628feec from cdb-0.75 per http://cr.yp.to/cdb.html,
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18 --len;
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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,
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21 }