blob: 9b83c53c4fe41985e09090140d51bc21b0195fa5 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
|
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
*
* LibTomCrypt is a library that provides various cryptographic
* algorithms in a highly modular and flexible manner.
*
* The library is free for all purposes without any express
* guarantee it works.
*
* Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.org
*/
/**
@file ocb_ntz.c
OCB implementation, internal function, by Tom St Denis
*/
#include "tomcrypt.h"
#ifdef OCB_MODE
/**
Returns the number of leading zero bits [from lsb up]
@param x The 32-bit value to observe
@return The number of bits [from the lsb up] that are zero
*/
int ocb_ntz(unsigned long x)
{
int c;
x &= 0xFFFFFFFFUL;
c = 0;
while ((x & 1) == 0) {
++c;
x >>= 1;
}
return c;
}
#endif
/* $Source: /cvs/libtom/libtomcrypt/src/encauth/ocb/ocb_ntz.c,v $ */
/* $Revision: 1.3 $ */
/* $Date: 2005/05/05 14:35:58 $ */
|
