1 /* $NetBSD: bn_mp_clamp.c,v 1.1.1.1 2011/04/13 18:14:54 elric Exp $ */ 2 3 #include <tommath.h> 4 #ifdef BN_MP_CLAMP_C 5 /* LibTomMath, multiple-precision integer library -- Tom St Denis 6 * 7 * LibTomMath is a library that provides multiple-precision 8 * integer arithmetic as well as number theoretic functionality. 9 * 10 * The library was designed directly after the MPI library by 11 * Michael Fromberger but has been written from scratch with 12 * additional optimizations in place. 13 * 14 * The library is free for all purposes without any express 15 * guarantee it works. 16 * 17 * Tom St Denis, tomstdenis@gmail.com, http://libtom.org 18 */ 19 20 /* trim unused digits 21 * 22 * This is used to ensure that leading zero digits are 23 * trimed and the leading "used" digit will be non-zero 24 * Typically very fast. Also fixes the sign if there 25 * are no more leading digits 26 */ 27 void 28 mp_clamp (mp_int * a) 29 { 30 /* decrease used while the most significant digit is 31 * zero. 32 */ 33 while (a->used > 0 && a->dp[a->used - 1] == 0) { 34 --(a->used); 35 } 36 37 /* reset the sign flag if used == 0 */ 38 if (a->used == 0) { 39 a->sign = MP_ZPOS; 40 } 41 } 42 #endif 43 44 /* Source: /cvs/libtom/libtommath/bn_mp_clamp.c,v */ 45 /* Revision: 1.4 */ 46 /* Date: 2006/12/28 01:25:13 */ 47