git.zerfleddert.de Git - proxmark3-svn/blob - common/parity.h

   1 //-----------------------------------------------------------------------------
   2 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
   3 // at your option, any later version. See the LICENSE.txt file for the text of
   4 // the license.
   5 //-----------------------------------------------------------------------------
   6 // Generic CRC calculation code.
   7 //-----------------------------------------------------------------------------
   8
   9 #ifndef __PARITY_H
  10 #define __PARITY_H
  11
  12 #include <stdint.h>
  13
  14 extern const uint8_t OddByteParity[256];
  15
  16 static inline uint8_t oddparity8(uint8_t bt)
  17 {
  18         return OddByteParity[bt];
  19 }
  20
  21
  22 extern const uint8_t EvenByteParity[256];
  23
  24 static inline uint8_t evenparity8(const uint8_t bt)
  25 {
  26         return EvenByteParity[bt];
  27 }
  28
  29
  30 static inline uint8_t evenparity32(uint32_t x)
  31 {
  32         x ^= x >> 16;
  33         x ^= x >> 8;
  34         return EvenByteParity[x & 0xff];
  35 }
  36
  37
  38 #endif /* __PARITY_H */