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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 /* trim unused digits |
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18 * |
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19 * This is used to ensure that leading zero digits are |
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20 * trimed and the leading "used" digit will be non-zero |
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21 * Typically very fast. Also fixes the sign if there |
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22 * are no more leading digits |
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23 */ |
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24 void |
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25 mp_clamp (mp_int * a) |
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26 { |
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27 /* decrease used while the most significant digit is |
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28 * zero. |
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29 */ |
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30 while (a->used > 0 && a->dp[a->used - 1] == 0) { |
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31 --(a->used); |
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32 } |
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33 |
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34 /* reset the sign flag if used == 0 */ |
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35 if (a->used == 0) { |
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36 a->sign = MP_ZPOS; |
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37 } |
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38 } |
