diff options
author | Yang Zhang <yang.z.zhang@intel.com> | 2015-08-28 09:58:54 +0800 |
---|---|---|
committer | Yang Zhang <yang.z.zhang@intel.com> | 2015-09-01 12:44:00 +0800 |
commit | e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch) | |
tree | 66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/ipxe/src/crypto/crc32.c | |
parent | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff) |
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/ipxe/src/crypto/crc32.c')
-rw-r--r-- | qemu/roms/ipxe/src/crypto/crc32.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/crypto/crc32.c b/qemu/roms/ipxe/src/crypto/crc32.c new file mode 100644 index 000000000..cfef68c02 --- /dev/null +++ b/qemu/roms/ipxe/src/crypto/crc32.c @@ -0,0 +1,55 @@ +/* + * Little-endian CRC32 implementation. + * + * Copyright (c) 2009 Joshua Oreman <oremanj@rwcr.net>. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + */ + +FILE_LICENCE ( GPL2_OR_LATER ); + +#include <ipxe/crc32.h> + +#define CRCPOLY 0xedb88320 + +/** + * Calculate 32-bit little-endian CRC checksum + * + * @v seed Initial value + * @v data Data to checksum + * @v len Length of data + * + * Usually @a seed is initially zero or all one bits, depending on the + * protocol. To continue a CRC checksum over multiple calls, pass the + * return value from one call as the @a seed parameter to the next. + */ +u32 crc32_le ( u32 seed, const void *data, size_t len ) +{ + u32 crc = seed; + const u8 *src = data; + u32 mult; + int i; + + while ( len-- ) { + crc ^= *src++; + for ( i = 0; i < 8; i++ ) { + mult = ( crc & 1 ) ? CRCPOLY : 0; + crc = ( crc >> 1 ) ^ mult; + } + } + + return crc; +} |