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Diffstat (limited to 'fs/zfs/zfs_lzjb.c')
-rw-r--r--fs/zfs/zfs_lzjb.c97
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 0000000..b22d7e1
--- /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;
+}