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1 /* LibTomMath, multiple-precision integer library -- Tom St Denis |
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2 * |
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3 * LibTomMath is a library that provides multiple-precision |
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4 * integer arithmetic as well as number theoretic functionality. |
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5 * |
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6 * The library was designed directly after the MPI library by |
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7 * Michael Fromberger but has been written from scratch with |
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8 * additional optimizations in place. |
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9 * |
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10 * The library is free for all purposes without any express |
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11 * guarantee it works. |
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12 * |
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13 * Tom St Denis, [email protected], http://math.libtomcrypt.org |
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14 */ |
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15 #include <tommath.h> |
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16 |
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17 /* compare maginitude of two ints (unsigned) */ |
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18 int mp_cmp_mag (mp_int * a, mp_int * b) |
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19 { |
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20 int n; |
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21 mp_digit *tmpa, *tmpb; |
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22 |
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23 /* compare based on # of non-zero digits */ |
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24 if (a->used > b->used) { |
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25 return MP_GT; |
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26 } |
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27 |
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28 if (a->used < b->used) { |
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29 return MP_LT; |
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30 } |
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31 |
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32 /* alias for a */ |
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33 tmpa = a->dp + (a->used - 1); |
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34 |
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35 /* alias for b */ |
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36 tmpb = b->dp + (a->used - 1); |
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37 |
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38 /* compare based on digits */ |
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39 for (n = 0; n < a->used; ++n, --tmpa, --tmpb) { |
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40 if (*tmpa > *tmpb) { |
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41 return MP_GT; |
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42 } |
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43 |
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44 if (*tmpa < *tmpb) { |
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45 return MP_LT; |
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46 } |
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47 } |
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48 return MP_EQ; |
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49 } |
