LXR linux/include/linux/crc32.h

   1/*
   2 * crc32.h
   3 * See linux/lib/crc32.c for license and changes
   4 */
   5#ifndef _LINUX_CRC32_H
   6#define _LINUX_CRC32_H
   7
   8#include <linux/types.h>
   9#include <linux/bitrev.h>
  10
  11extern u32  crc32_le(u32 crc, unsigned char const *p, size_t len);
  12extern u32  crc32_be(u32 crc, unsigned char const *p, size_t len);
  13
  14#define crc32(seed, data, length)  crc32_le(seed, (unsigned char const *)data, length)
  15
  16/*
  17 * Helpers for hash table generation of ethernet nics:
  18 *
  19 * Ethernet sends the least significant bit of a byte first, thus crc32_le
  20 * is used. The output of crc32_le is bit reversed [most significant bit
  21 * is in bit nr 0], thus it must be reversed before use. Except for
  22 * nics that bit swap the result internally...
  23 */
  24#define ether_crc(length, data)    bitrev32(crc32_le(~0, data, length))
  25#define ether_crc_le(length, data) crc32_le(~0, data, length)
  26
  27#endif /* _LINUX_CRC32_H */
  28