Mercurial > dropbear
annotate libtommath/bn_mp_clamp.c @ 1530:63fa53d3b6c7 fuzz
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author | Matt Johnston <matt@ucc.asn.au> |
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date | Wed, 21 Feb 2018 21:59:52 +0800 |
parents | 8bba51a55704 |
children | f52919ffd3b1 |
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1436 | 1 #include <tommath_private.h> |
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2 #ifdef BN_MP_CLAMP_C |
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3 /* LibTomMath, multiple-precision integer library -- Tom St Denis |
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4 * |
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5 * LibTomMath is a library that provides multiple-precision |
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6 * integer arithmetic as well as number theoretic functionality. |
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7 * |
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8 * The library was designed directly after the MPI library by |
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9 * Michael Fromberger but has been written from scratch with |
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10 * additional optimizations in place. |
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11 * |
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12 * The library is free for all purposes without any express |
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13 * guarantee it works. |
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14 * |
1436 | 15 * Tom St Denis, [email protected], http://libtom.org |
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16 */ |
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17 |
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18 /* trim unused digits |
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19 * |
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20 * This is used to ensure that leading zero digits are |
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21 * trimed and the leading "used" digit will be non-zero |
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22 * Typically very fast. Also fixes the sign if there |
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23 * are no more leading digits |
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24 */ |
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25 void |
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26 mp_clamp (mp_int * a) |
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27 { |
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28 /* decrease used while the most significant digit is |
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29 * zero. |
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30 */ |
1436 | 31 while ((a->used > 0) && (a->dp[a->used - 1] == 0)) { |
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32 --(a->used); |
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33 } |
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34 |
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35 /* reset the sign flag if used == 0 */ |
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36 if (a->used == 0) { |
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37 a->sign = MP_ZPOS; |
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38 } |
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39 } |
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40 #endif |
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41 |
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Update to libtommath v1.0.1
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42 /* ref: $Format:%D$ */ |
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43 /* git commit: $Format:%H$ */ |
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44 /* commit time: $Format:%ai$ */ |