tommath/bn_mp_clamp.c

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#include "tommath_private.h"
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#ifdef BN_MP_CLAMP_C
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/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
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* LibTomMath is a library that provides multiple-precision
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* integer arithmetic as well as number theoretic functionality.
*
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* The library was designed directly after the MPI library by
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* Michael Fromberger but has been written from scratch with
* additional optimizations in place.
*
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* SPDX-License-Identifier: Unlicense
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*/
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/* trim unused digits
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*
* This is used to ensure that leading zero digits are
* trimed and the leading "used" digit will be non-zero
* Typically very fast. Also fixes the sign if there
* are no more leading digits
*/
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void mp_clamp(mp_int *a)
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{
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/* decrease used while the most significant digit is
* zero.
*/
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while ((a->used > 0) && (a->dp[a->used - 1] == 0u)) {
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--(a->used);
}
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/* reset the sign flag if used == 0 */
if (a->used == 0) {
a->sign = MP_ZPOS;
}
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}
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#endif
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/* ref: $Format:%D$ */
/* git commit: $Format:%H$ */
/* commit time: $Format:%ai$ */