| // SPDX-License-Identifier: BSD-2-Clause |
| /* 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 ocb_ntz.c |
| OCB implementation, internal function, by Tom St Denis |
| */ |
| |
| #include "tomcrypt_private.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 |
| |
| /* ref: $Format:%D$ */ |
| /* git commit: $Format:%H$ */ |
| /* commit time: $Format:%ai$ */ |