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1 #include <tommath.h> |
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2 #ifdef BN_MP_NEG_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 * |
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15 * Tom St Denis, [email protected], http://math.libtomcrypt.com |
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16 */ |
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17 |
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18 /* b = -a */ |
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19 int mp_neg (mp_int * a, mp_int * b) |
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20 { |
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21 int res; |
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22 if (a != b) { |
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23 if ((res = mp_copy (a, b)) != MP_OKAY) { |
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24 return res; |
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25 } |
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26 } |
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27 |
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28 if (mp_iszero(b) != MP_YES) { |
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29 b->sign = (a->sign == MP_ZPOS) ? MP_NEG : MP_ZPOS; |
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30 } else { |
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31 b->sign = MP_ZPOS; |
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32 } |
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33 |
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34 return MP_OKAY; |
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35 } |
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36 #endif |
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37 |
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38 /* $Source: /cvs/libtom/libtommath/bn_mp_neg.c,v $ */ |
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39 /* $Revision: 1.3 $ */ |
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40 /* $Date: 2006/03/31 14:18:44 $ */ |
