view libtomcrypt/src/encauth/ocb3/ocb3_int_ntz.c @ 1749:32307118bc26

Add ubsan fuzz run to Travis CI too
author Matt Johnston <matt@ucc.asn.au>
date Mon, 19 Oct 2020 23:38:11 +0800
parents 6dba84798cd5
children
line wrap: on
line source

/* 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.
 */

/**
   @file ocb3_int_ntz.c
   OCB implementation, INTERNAL ONLY helper, by Tom St Denis
*/
#include "tomcrypt.h"

#ifdef LTC_OCB3_MODE

/**
   Returns the number of leading zero bits [from lsb up] (internal function)
   @param x  The 32-bit value to observe
   @return The number of bits [from the lsb up] that are zero
*/
int ocb3_int_ntz(unsigned long x)
{
   int c;
   x &= 0xFFFFFFFFUL;
   c = 0;
   while ((x & 1) == 0) {
      ++c;
      x >>= 1;
   }
   return c;
}

#endif

/* ref:         $Format:%D$ */
/* git commit:  $Format:%H$ */
/* commit time: $Format:%ai$ */