Donatien Garnier
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.
math/mul/fp_mul_2d.c@0:35aa5be3b78d, 2014-06-06 (annotated)
- Committer:
- MiniTLS
- Date:
- Fri Jun 06 10:49:02 2014 +0000
- Revision:
- 0:35aa5be3b78d
Initial commit
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| MiniTLS | 0:35aa5be3b78d | 1 | /* TomsFastMath, a fast ISO C bignum library. |
| MiniTLS | 0:35aa5be3b78d | 2 | * |
| MiniTLS | 0:35aa5be3b78d | 3 | * This project is meant to fill in where LibTomMath |
| MiniTLS | 0:35aa5be3b78d | 4 | * falls short. That is speed ;-) |
| MiniTLS | 0:35aa5be3b78d | 5 | * |
| MiniTLS | 0:35aa5be3b78d | 6 | * This project is public domain and free for all purposes. |
| MiniTLS | 0:35aa5be3b78d | 7 | * |
| MiniTLS | 0:35aa5be3b78d | 8 | * Tom St Denis, tomstdenis@gmail.com |
| MiniTLS | 0:35aa5be3b78d | 9 | */ |
| MiniTLS | 0:35aa5be3b78d | 10 | #include <tfm.h> |
| MiniTLS | 0:35aa5be3b78d | 11 | |
| MiniTLS | 0:35aa5be3b78d | 12 | /* c = a * 2**d */ |
| MiniTLS | 0:35aa5be3b78d | 13 | void fp_mul_2d(fp_int *a, int b, fp_int *c) |
| MiniTLS | 0:35aa5be3b78d | 14 | { |
| MiniTLS | 0:35aa5be3b78d | 15 | fp_digit carry, carrytmp, shift; |
| MiniTLS | 0:35aa5be3b78d | 16 | int x; |
| MiniTLS | 0:35aa5be3b78d | 17 | |
| MiniTLS | 0:35aa5be3b78d | 18 | /* copy it */ |
| MiniTLS | 0:35aa5be3b78d | 19 | fp_copy(a, c); |
| MiniTLS | 0:35aa5be3b78d | 20 | |
| MiniTLS | 0:35aa5be3b78d | 21 | /* handle whole digits */ |
| MiniTLS | 0:35aa5be3b78d | 22 | if (b >= DIGIT_BIT) { |
| MiniTLS | 0:35aa5be3b78d | 23 | fp_lshd(c, b/DIGIT_BIT); |
| MiniTLS | 0:35aa5be3b78d | 24 | } |
| MiniTLS | 0:35aa5be3b78d | 25 | b %= DIGIT_BIT; |
| MiniTLS | 0:35aa5be3b78d | 26 | |
| MiniTLS | 0:35aa5be3b78d | 27 | /* shift the digits */ |
| MiniTLS | 0:35aa5be3b78d | 28 | if (b != 0) { |
| MiniTLS | 0:35aa5be3b78d | 29 | carry = 0; |
| MiniTLS | 0:35aa5be3b78d | 30 | shift = DIGIT_BIT - b; |
| MiniTLS | 0:35aa5be3b78d | 31 | for (x = 0; x < c->used; x++) { |
| MiniTLS | 0:35aa5be3b78d | 32 | carrytmp = c->dp[x] >> shift; |
| MiniTLS | 0:35aa5be3b78d | 33 | c->dp[x] = (c->dp[x] << b) + carry; |
| MiniTLS | 0:35aa5be3b78d | 34 | carry = carrytmp; |
| MiniTLS | 0:35aa5be3b78d | 35 | } |
| MiniTLS | 0:35aa5be3b78d | 36 | /* store last carry if room */ |
| MiniTLS | 0:35aa5be3b78d | 37 | if (carry && x < FP_SIZE) { |
| MiniTLS | 0:35aa5be3b78d | 38 | c->dp[c->used++] = carry; |
| MiniTLS | 0:35aa5be3b78d | 39 | } |
| MiniTLS | 0:35aa5be3b78d | 40 | } |
| MiniTLS | 0:35aa5be3b78d | 41 | fp_clamp(c); |
| MiniTLS | 0:35aa5be3b78d | 42 | } |
| MiniTLS | 0:35aa5be3b78d | 43 | |
| MiniTLS | 0:35aa5be3b78d | 44 | |
| MiniTLS | 0:35aa5be3b78d | 45 | /* $Source: /cvs/libtom/tomsfastmath/src/mul/fp_mul_2d.c,v $ */ |
| MiniTLS | 0:35aa5be3b78d | 46 | /* $Revision: 1.1 $ */ |
| MiniTLS | 0:35aa5be3b78d | 47 | /* $Date: 2006/12/31 21:25:53 $ */ |
