annotate bn_mp_shrink.c @ 2:86e0b50a9b58 libtommath-orig ltm-0.30-orig

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author Matt Johnston <matt@ucc.asn.au>
date Mon, 31 May 2004 18:25:22 +0000
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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 /* shrink a bignum */
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18 int mp_shrink (mp_int * a)
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19 {
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20 mp_digit *tmp;
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21 if (a->alloc != a->used && a->used > 0) {
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22 if ((tmp = OPT_CAST(mp_digit) XREALLOC (a->dp, sizeof (mp_digit) * a->used)) == NULL) {
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23 return MP_MEM;
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24 }
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25 a->dp = tmp;
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26 a->alloc = a->used;
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27 }
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28 return MP_OKAY;
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29 }