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comparison libtommath/bn_mp_count_bits.c @ 1655:f52919ffd3b1

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update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79) * make key-generation compliant to FIPS 186.4 * fix includes in tommath_class.h * update fuzzcorpus instead of error-out * fixup fuzzing make-targets * update Makefile.in * apply necessary patches to ltm sources * clean-up not required ltm files * update to vanilla ltm 1.1.0 this already only contains the required files * remove set/get double
author Steffen Jaeckel <s_jaeckel@gmx.de>
date Mon, 16 Sep 2019 15:50:38 +0200
parents 8bba51a55704
children 1051e4eea25a
comparison
equal deleted inserted replaced
1654:cc0fc5131c5c 1655:f52919ffd3b1
1 #include <tommath_private.h> 1 #include "tommath_private.h"
2 #ifdef BN_MP_COUNT_BITS_C 2 #ifdef BN_MP_COUNT_BITS_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.
7 * 7 *
8 * The library was designed directly after the MPI library by 8 * The library was designed directly after the MPI library by
9 * Michael Fromberger but has been written from scratch with 9 * Michael Fromberger but has been written from scratch with
10 * additional optimizations in place. 10 * additional optimizations in place.
11 * 11 *
12 * The library is free for all purposes without any express 12 * SPDX-License-Identifier: Unlicense
13 * guarantee it works.
14 *
15 * Tom St Denis, [email protected], http://libtom.org
16 */ 13 */
17 14
18 /* returns the number of bits in an int */ 15 /* returns the number of bits in an int */
19 int 16 int mp_count_bits(const mp_int *a)
20 mp_count_bits (mp_int * a)
21 { 17 {
22 int r; 18 int r;
23 mp_digit q; 19 mp_digit q;
24 20
25 /* shortcut */ 21 /* shortcut */
26 if (a->used == 0) { 22 if (a->used == 0) {
27 return 0; 23 return 0;
28 } 24 }
29 25
30 /* get number of digits and add that */ 26 /* get number of digits and add that */
31 r = (a->used - 1) * DIGIT_BIT; 27 r = (a->used - 1) * DIGIT_BIT;
32 28
33 /* take the last digit and count the bits in it */ 29 /* take the last digit and count the bits in it */
34 q = a->dp[a->used - 1]; 30 q = a->dp[a->used - 1];
35 while (q > ((mp_digit) 0)) { 31 while (q > (mp_digit)0) {
36 ++r; 32 ++r;
37 q >>= ((mp_digit) 1); 33 q >>= (mp_digit)1;
38 } 34 }
39 return r; 35 return r;
40 } 36 }
41 #endif 37 #endif
42 38
43 /* ref: $Format:%D$ */ 39 /* ref: HEAD -> master, tag: v1.1.0 */
44 /* git commit: $Format:%H$ */ 40 /* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
45 /* commit time: $Format:%ai$ */ 41 /* commit time: 2019-01-28 20:32:32 +0100 */