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/*
* crc32.h
* See linux/lib/crc32.c for license and changes
*/
#ifndef _LINUX_CRC32_H
#define _LINUX_CRC32_H
#include <linux/types.h>
#include <linux/bitrev.h>
extern u32 crc32_le(u32 crc, unsigned char const *p, size_t len);
extern u32 crc32_be(u32 crc, unsigned char const *p, size_t len);
/**
* crc32_le_combine - Combine two crc32 check values into one. For two
* sequences of bytes, seq1 and seq2 with lengths len1
* and len2, crc32_le() check values were calculated
* for each, crc1 and crc2.
*
* @crc1: crc32 of the first block
* @crc2: crc32 of the second block
* @len2: length of the second block
*
* Return: The crc32_le() check value of seq1 and seq2 concatenated,
* requiring only crc1, crc2, and len2. Note: If seq_full denotes
* the concatenated memory area of seq1 with seq2, and crc_full
* the crc32_le() value of seq_full, then crc_full ==
* crc32_le_combine(crc1, crc2, len2) when crc_full was seeded
* with the same initializer as crc1, and crc2 seed was 0. See
* also crc32_combine_test().
*/
u32 __attribute_const__ crc32_le_shift(u32 crc, size_t len);
static inline u32 crc32_le_combine(u32 crc1, u32 crc2, size_t len2)
{
return crc32_le_shift(crc1, len2) ^ crc2;
}
extern u32 __crc32c_le(u32 crc, unsigned char const *p, size_t len);
/**
* __crc32c_le_combine - Combine two crc32c check values into one. For two
* sequences of bytes, seq1 and seq2 with lengths len1
* and len2, __crc32c_le() check values were calculated
* for each, crc1 and crc2.
*
* @crc1: crc32c of the first block
* @crc2: crc32c of the second block
* @len2: length of the second block
*
* Return: The __crc32c_le() check value of seq1 and seq2 concatenated,
* requiring only crc1, crc2, and len2. Note: If seq_full denotes
* the concatenated memory area of seq1 with seq2, and crc_full
* the __crc32c_le() value of seq_full, then crc_full ==
* __crc32c_le_combine(crc1, crc2, len2) when crc_full was
* seeded with the same initializer as crc1, and crc2 seed
* was 0. See also crc32c_combine_test().
*/
u32 __attribute_const__ __crc32c_le_shift(u32 crc, size_t len);
static inline u32 __crc32c_le_combine(u32 crc1, u32 crc2, size_t len2)
{
return __crc32c_le_shift(crc1, len2) ^ crc2;
}
#define crc32(seed, data, length) crc32_le(seed, (unsigned char const *)(data), length)
/*
* Helpers for hash table generation of ethernet nics:
*
* Ethernet sends the least significant bit of a byte first, thus crc32_le
* is used. The output of crc32_le is bit reversed [most significant bit
* is in bit nr 0], thus it must be reversed before use. Except for
* nics that bit swap the result internally...
*/
#define ether_crc(length, data) bitrev32(crc32_le(~0, data, length))
#define ether_crc_le(length, data) crc32_le(~0, data, length)
#endif /* _LINUX_CRC32_H */
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