annotate tomsfastmath/src/divide/fp_mod.c @ 643:a362b62d38b2 dropbear-tfm

Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a with Makefile.in renamed
author Matt Johnston <matt@ucc.asn.au>
date Wed, 23 Nov 2011 18:10:20 +0700
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1 /* TomsFastMath, a fast ISO C bignum library.
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2 *
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3 * This project is meant to fill in where LibTomMath
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4 * falls short. That is speed ;-)
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5 *
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6 * This project is public domain and free for all purposes.
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7 *
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8 * Tom St Denis, [email protected]
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9 */
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10 #include <tfm.h>
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12 /* c = a mod b, 0 <= c < b */
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13 int fp_mod(fp_int *a, fp_int *b, fp_int *c)
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14 {
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15 fp_int t;
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16 int err;
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18 fp_zero(&t);
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19 if ((err = fp_div(a, b, NULL, &t)) != FP_OKAY) {
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20 return err;
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21 }
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22 if (t.sign != b->sign) {
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23 fp_add(&t, b, c);
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24 } else {
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25 fp_copy(&t, c);
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26 }
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27 return FP_OKAY;
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28 }
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32 /* $Source$ */
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33 /* $Revision$ */
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34 /* $Date$ */