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/* 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://libtom.org
*/
/**
@file ocb_ntz.c
OCB implementation, internal function, by Tom St Denis
*/
#include "tomcrypt.h"
#ifdef LTC_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
/* $Source$ */
/* $Revision$ */
/* $Date$ */
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