LXR uboot/fs/zfs/zfs

   1/*
   2 *  GRUB  --  GRand Unified Bootloader
   3 *  Copyright (C) 1999,2000,2001,2002,2003,2004  Free Software Foundation, Inc.
   4 *
   5 * SPDX-License-Identifier:     GPL-2.0+
   6 */
   7/*
   8 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
   9 * Use is subject to license terms.
  10 */
  11
  12#include <common.h>
  13#include <malloc.h>
  14#include <linux/stat.h>
  15#include <linux/time.h>
  16#include <linux/ctype.h>
  17#include <asm/byteorder.h>
  18#include "zfs_common.h"
  19
  20#include <zfs/zfs.h>
  21#include <zfs/zio.h>
  22#include <zfs/dnode.h>
  23#include <zfs/uberblock_impl.h>
  24#include <zfs/vdev_impl.h>
  25#include <zfs/zio_checksum.h>
  26#include <zfs/zap_impl.h>
  27#include <zfs/zap_leaf.h>
  28#include <zfs/zfs_znode.h>
  29#include <zfs/dmu.h>
  30#include <zfs/dmu_objset.h>
  31#include <zfs/dsl_dir.h>
  32#include <zfs/dsl_dataset.h>
  33
  34#define MATCH_BITS      6
  35#define MATCH_MIN       3
  36#define OFFSET_MASK     ((1 << (16 - MATCH_BITS)) - 1)
  37
  38/*
  39 * Decompression Entry - lzjb
  40 */
  41#ifndef NBBY
  42#define NBBY    8
  43#endif
  44
  45int
  46lzjb_decompress(void *s_start, void *d_start, uint32_t s_len,
  47                                uint32_t d_len)
  48{
  49        uint8_t *src = s_start;
  50        uint8_t *dst = d_start;
  51        uint8_t *d_end = (uint8_t *) d_start + d_len;
  52        uint8_t *s_end = (uint8_t *) s_start + s_len;
  53        uint8_t *cpy, copymap = 0;
  54        int copymask = 1 << (NBBY - 1);
  55
  56        while (dst < d_end && src < s_end) {
  57                if ((copymask <<= 1) == (1 << NBBY)) {
  58                        copymask = 1;
  59                        copymap = *src++;
  60                }
  61                if (src >= s_end) {
  62                        printf("lzjb decompression failed\n");
  63                        return ZFS_ERR_BAD_FS;
  64                }
  65                if (copymap & copymask) {
  66                        int mlen = (src[0] >> (NBBY - MATCH_BITS)) + MATCH_MIN;
  67                        int offset = ((src[0] << NBBY) | src[1]) & OFFSET_MASK;
  68                        src += 2;
  69                        cpy = dst - offset;
  70                        if (src > s_end || cpy < (uint8_t *) d_start) {
  71                                printf("lzjb decompression failed\n");
  72                                return ZFS_ERR_BAD_FS;
  73                        }
  74                        while (--mlen >= 0 && dst < d_end)
  75                                *dst++ = *cpy++;
  76                } else {
  77                        *dst++ = *src++;
  78                }
  79        }
  80        if (dst < d_end) {
  81                printf("lzjb decompression failed\n");
  82                return ZFS_ERR_BAD_FS;
  83        }
  84        return ZFS_ERR_NONE;
  85}
  86