Mercurial > dovecot > core-2.2

annotate src/lib/primes.c @ 22664:fea53c2725c0

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director: Fix director_max_parallel_moves/kicks type Should be uint, not time.
author Timo Sirainen <timo.sirainen@dovecot.fi>
date Thu, 09 Nov 2017 12:24:16 +0200
parents 2e2563132d5f
children cb108f786fb4
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2e2563132d5f Updated copyright notices to include the year 2017.
Stephan Bosch <stephan.bosch@dovecot.fi>
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1 /* Copyright (c) 2013-2017 Dovecot authors, see the included COPYING file */
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2
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3 #include "lib.h"
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4 #include "primes.h"
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5
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6 static const unsigned int primes[] = {
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c55a66afddea primes_closest(): Use exponentially growing primes.
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7 #define PRIME_SKIP_COUNT 3
c55a66afddea primes_closest(): Use exponentially growing primes.
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8 17,
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9 37,
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10 67,
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11 131,
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12 257, /* next from 2^8 */
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13 521,
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14 1031,
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19 32771,
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20 65537, /* next from 2^16 */
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21 131101,
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23 524309,
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24 1048583,
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25 2097169,
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27 8388617,
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28 16777259, /* next from 2^24 */
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29 33554467,
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30 67108879,
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31 134217757,
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32 268435459,
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33 536870923,
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34 1073741827,
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35 2147483659U,
a035febf39d4 Compiler warning fix.
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36 4294967291U /* previous from 2^32 */
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37 };
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38
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39 unsigned int primes_closest(unsigned int num)
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40 {
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41 unsigned int i;
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42
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43 for (i = 31; i > PRIME_SKIP_COUNT; i--) {
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44 if ((num & (1U << i)) != 0)
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45 return primes[i - PRIME_SKIP_COUNT];
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46 }
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47 return primes[0];
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48 }