zfs_lzjb.c 1.9 KB

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