A super trimmed down TLS stack, GPL licensed
Dependents: MiniTLS-HTTPS-Example
MiniTLS - A super trimmed down TLS/SSL Library for embedded devices Author: Donatien Garnier Copyright (C) 2013-2014 AppNearMe Ltd
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
Diff: math/bit/fp_div_2.c
- Revision:
- 0:35aa5be3b78d
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/math/bit/fp_div_2.c Fri Jun 06 10:49:02 2014 +0000 @@ -0,0 +1,53 @@ +/* TomsFastMath, a fast ISO C bignum library. + * + * This project is meant to fill in where LibTomMath + * falls short. That is speed ;-) + * + * This project is public domain and free for all purposes. + * + * Tom St Denis, tomstdenis@gmail.com + */ +#include <tfm.h> + +/* b = a/2 */ +void fp_div_2(fp_int * a, fp_int * b) +{ + int x, oldused; + + oldused = b->used; + b->used = a->used; + { + register fp_digit r, rr, *tmpa, *tmpb; + + /* source alias */ + tmpa = a->dp + b->used - 1; + + /* dest alias */ + tmpb = b->dp + b->used - 1; + + /* carry */ + r = 0; + for (x = b->used - 1; x >= 0; x--) { + /* get the carry for the next iteration */ + rr = *tmpa & 1; + + /* shift the current digit, add in carry and store */ + *tmpb-- = (*tmpa-- >> 1) | (r << (DIGIT_BIT - 1)); + + /* forward carry to next iteration */ + r = rr; + } + + /* zero excess digits */ + tmpb = b->dp + b->used; + for (x = b->used; x < oldused; x++) { + *tmpb++ = 0; + } + } + b->sign = a->sign; + fp_clamp (b); +} + +/* $Source: /cvs/libtom/tomsfastmath/src/bit/fp_div_2.c,v $ */ +/* $Revision: 1.1 $ */ +/* $Date: 2006/12/31 21:25:53 $ */