u-boot/fs/zfs/zfs_lzjb.c

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/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc.
*
* 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
* (at your option) 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
* Copyright 2007 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#include <common.h>
#include <malloc.h>
#include <linux/stat.h>
#include <linux/time.h>
#include <linux/ctype.h>
#include <asm/byteorder.h>
#include "zfs_common.h"
#include <zfs/zfs.h>
#include <zfs/zio.h>
#include <zfs/dnode.h>
#include <zfs/uberblock_impl.h>
#include <zfs/vdev_impl.h>
#include <zfs/zio_checksum.h>
#include <zfs/zap_impl.h>
#include <zfs/zap_leaf.h>
#include <zfs/zfs_znode.h>
#include <zfs/dmu.h>
#include <zfs/dmu_objset.h>
#include <zfs/dsl_dir.h>
#include <zfs/dsl_dataset.h>
#define MATCH_BITS 6
#define MATCH_MIN 3
#define OFFSET_MASK ((1 << (16 - MATCH_BITS)) - 1)
/*
* Decompression Entry - lzjb
*/
#ifndef NBBY
#define NBBY 8
#endif
int
lzjb_decompress(void *s_start, void *d_start, uint32_t s_len,
uint32_t d_len)
{
uint8_t *src = s_start;
uint8_t *dst = d_start;
uint8_t *d_end = (uint8_t *) d_start + d_len;
uint8_t *s_end = (uint8_t *) s_start + s_len;
uint8_t *cpy, copymap = 0;
int copymask = 1 << (NBBY - 1);
while (dst < d_end && src < s_end) {
if ((copymask <<= 1) == (1 << NBBY)) {
copymask = 1;
copymap = *src++;
}
if (src >= s_end) {
printf("lzjb decompression failed\n");
return ZFS_ERR_BAD_FS;
}
if (copymap & copymask) {
int mlen = (src[0] >> (NBBY - MATCH_BITS)) + MATCH_MIN;
int offset = ((src[0] << NBBY) | src[1]) & OFFSET_MASK;
src += 2;
cpy = dst - offset;
if (src > s_end || cpy < (uint8_t *) d_start) {
printf("lzjb decompression failed\n");
return ZFS_ERR_BAD_FS;
}
while (--mlen >= 0 && dst < d_end)
*dst++ = *cpy++;
} else {
*dst++ = *src++;
}
}
if (dst < d_end) {
printf("lzjb decompression failed\n");
return ZFS_ERR_BAD_FS;
}
return ZFS_ERR_NONE;
}