Linux Kernel  3.7.1
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crc32.h
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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 
11 extern u32 crc32_le(u32 crc, unsigned char const *p, size_t len);
12 extern u32 crc32_be(u32 crc, unsigned char const *p, size_t len);
13 
14 extern u32 __crc32c_le(u32 crc, unsigned char const *p, size_t len);
15 
16 #define crc32(seed, data, length) crc32_le(seed, (unsigned char const *)(data), length)
17 
18 /*
19  * Helpers for hash table generation of ethernet nics:
20  *
21  * Ethernet sends the least significant bit of a byte first, thus crc32_le
22  * is used. The output of crc32_le is bit reversed [most significant bit
23  * is in bit nr 0], thus it must be reversed before use. Except for
24  * nics that bit swap the result internally...
25  */
26 #define ether_crc(length, data) bitrev32(crc32_le(~0, data, length))
27 #define ether_crc_le(length, data) crc32_le(~0, data, length)
28 
29 #endif /* _LINUX_CRC32_H */