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comparison libtommath/bn_mp_mod_2d.c @ 1439:8d24733026c5 coverity

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merge
author Matt Johnston <matt@ucc.asn.au>
date Sat, 24 Jun 2017 23:33:16 +0800
parents 60fc6476e044
children 8bba51a55704
comparison
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1400:238a439670f5 1439:8d24733026c5
1 #include <tommath.h> 1 #include <tommath_private.h>
2 #ifdef BN_MP_MOD_2D_C 2 #ifdef BN_MP_MOD_2D_C
3 /* LibTomMath, multiple-precision integer library -- Tom St Denis 3 /* LibTomMath, multiple-precision integer library -- Tom St Denis
4 * 4 *
5 * LibTomMath is a library that provides multiple-precision 5 * LibTomMath is a library that provides multiple-precision
6 * integer arithmetic as well as number theoretic functionality. 6 * integer arithmetic as well as number theoretic functionality.
10 * additional optimizations in place. 10 * additional optimizations in place.
11 * 11 *
12 * The library is free for all purposes without any express 12 * The library is free for all purposes without any express
13 * guarantee it works. 13 * guarantee it works.
14 * 14 *
15 * Tom St Denis, [email protected], http://math.libtomcrypt.com 15 * Tom St Denis, [email protected], http://libtom.org
16 */ 16 */
17 17
18 /* calc a value mod 2**b */ 18 /* calc a value mod 2**b */
19 int 19 int
20 mp_mod_2d (mp_int * a, int b, mp_int * c) 20 mp_mod_2d (mp_int * a, int b, mp_int * c)
37 if ((res = mp_copy (a, c)) != MP_OKAY) { 37 if ((res = mp_copy (a, c)) != MP_OKAY) {
38 return res; 38 return res;
39 } 39 }
40 40
41 /* zero digits above the last digit of the modulus */ 41 /* zero digits above the last digit of the modulus */
42 for (x = (b / DIGIT_BIT) + ((b % DIGIT_BIT) == 0 ? 0 : 1); x < c->used; x++) { 42 for (x = (b / DIGIT_BIT) + (((b % DIGIT_BIT) == 0) ? 0 : 1); x < c->used; x++) {
43 c->dp[x] = 0; 43 c->dp[x] = 0;
44 } 44 }
45 /* clear the digit that is not completely outside/inside the modulus */ 45 /* clear the digit that is not completely outside/inside the modulus */
46 c->dp[b / DIGIT_BIT] &= 46 c->dp[b / DIGIT_BIT] &=
47 (mp_digit) ((((mp_digit) 1) << (((mp_digit) b) % DIGIT_BIT)) - ((mp_digit) 1)); 47 (mp_digit) ((((mp_digit) 1) << (((mp_digit) b) % DIGIT_BIT)) - ((mp_digit) 1));
48 mp_clamp (c); 48 mp_clamp (c);
49 return MP_OKAY; 49 return MP_OKAY;
50 } 50 }
51 #endif 51 #endif
52 52
53 /* $Source: /cvs/libtom/libtommath/bn_mp_mod_2d.c,v $ */ 53 /* $Source$ */
54 /* $Revision: 1.3 $ */ 54 /* $Revision$ */
55 /* $Date: 2006/03/31 14:18:44 $ */ 55 /* $Date$ */