diff options
Diffstat (limited to 'fs/zfs/zfs_lzjb.c')
| -rw-r--r-- | fs/zfs/zfs_lzjb.c | 97 | 
1 files changed, 97 insertions, 0 deletions
| diff --git a/fs/zfs/zfs_lzjb.c b/fs/zfs/zfs_lzjb.c new file mode 100644 index 000000000..b22d7e1dd --- /dev/null +++ b/fs/zfs/zfs_lzjb.c @@ -0,0 +1,97 @@ +/* + *  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; +} |