include/util/crc32.h

0001 /*                    The Quest Operating System
0002  *  Copyright (C) 2005-2010  Richard West, Boston University
0003  *
0004  *  This program is free software: you can redistribute it and/or modify
0005  *  it under the terms of the GNU General Public License as published by
0006  *  the Free Software Foundation, either version 3 of the License, or
0007  *  (at your option) any later version.
0008  *
0009  *  This program is distributed in the hope that it will be useful,
0010  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
0011  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
0012  *  GNU General Public License for more details.
0013  *
0014  *  You should have received a copy of the GNU General Public License
0015  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
0016  */
0017
0018 /* Adopted from Linux */
0019
0020 #ifndef _UTIL_CRC32_H_
0021 #define _UTIL_CRC32_H_
0022
0023 #include <types.h>
0024
0025 extern u32  crc32_le(u32 crc, unsigned char const *p, size_t len);
0026 extern u32  crc32_be(u32 crc, unsigned char const *p, size_t len);
0027
0028 #define crc32(seed, data, length)  crc32_le(seed, (unsigned char const *)data, length)
0029
0030 /*
0031  * Helpers for hash table generation of ethernet nics:
0032  *
0033  * Ethernet sends the least significant bit of a byte first, thus crc32_le
0034  * is used. The output of crc32_le is bit reversed [most significant bit
0035  * is in bit nr 0], thus it must be reversed before use. Except for
0036  * nics that bit swap the result internally...
0037  */
0038 #define ether_crc(length, data)    bitrev32(crc32_le(~0, data, length))
0039 #define ether_crc_le(length, data) crc32_le(~0, data, length)
0040
0041
0042 #endif
0043
0044 /*
0045  * Local Variables:
0046  * indent-tabs-mode: nil
0047  * mode: C
0048  * c-file-style: "gnu"
0049  * c-basic-offset: 2
0050  * End:
0051  */
0052
0053 /* vi: set et sw=2 sts=2: */