lib/xz/xz_private.h

   1 /* SPDX-License-Identifier: 0BSD */
   2
   3 /*
   4  * Private includes and definitions
   5  *
   6  * Author: Lasse Collin <lasse.collin@tukaani.org>
   7  */
   8
   9 #ifndef XZ_PRIVATE_H
  10 #define XZ_PRIVATE_H
  11
  12 #ifdef __KERNEL__
  13 #       include <linux/xz.h>
  14 #       include <linux/kernel.h>
  15 #       include <linux/unaligned.h>
  16         /* XZ_PREBOOT may be defined only via decompress_unxz.c. */
  17 #       ifndef XZ_PREBOOT
  18 #               include <linux/slab.h>
  19 #               include <linux/vmalloc.h>
  20 #               include <linux/string.h>
  21 #               ifdef CONFIG_XZ_DEC_X86
  22 #                       define XZ_DEC_X86
  23 #               endif
  24 #               ifdef CONFIG_XZ_DEC_POWERPC
  25 #                       define XZ_DEC_POWERPC
  26 #               endif
  27 #               ifdef CONFIG_XZ_DEC_IA64
  28 #                       define XZ_DEC_IA64
  29 #               endif
  30 #               ifdef CONFIG_XZ_DEC_ARM
  31 #                       define XZ_DEC_ARM
  32 #               endif
  33 #               ifdef CONFIG_XZ_DEC_ARMTHUMB
  34 #                       define XZ_DEC_ARMTHUMB
  35 #               endif
  36 #               ifdef CONFIG_XZ_DEC_SPARC
  37 #                       define XZ_DEC_SPARC
  38 #               endif
  39 #               ifdef CONFIG_XZ_DEC_ARM64
  40 #                       define XZ_DEC_ARM64
  41 #               endif
  42 #               ifdef CONFIG_XZ_DEC_RISCV
  43 #                       define XZ_DEC_RISCV
  44 #               endif
  45 #               ifdef CONFIG_XZ_DEC_MICROLZMA
  46 #                       define XZ_DEC_MICROLZMA
  47 #               endif
  48 #               define memeq(a, b, size) (memcmp(a, b, size) == 0)
  49 #               define memzero(buf, size) memset(buf, 0, size)
  50 #       endif
  51 #       define get_le32(p) le32_to_cpup((const uint32_t *)(p))
  52 #else
  53         /*
  54          * For userspace builds, use a separate header to define the required
  55          * macros and functions. This makes it easier to adapt the code into
  56          * different environments and avoids clutter in the Linux kernel tree.
  57          */
  58 #       include "xz_config.h"
  59 #endif
  60
  61 /* If no specific decoding mode is requested, enable support for all modes. */
  62 #if !defined(XZ_DEC_SINGLE) && !defined(XZ_DEC_PREALLOC) \
  63                 && !defined(XZ_DEC_DYNALLOC)
  64 #       define XZ_DEC_SINGLE
  65 #       define XZ_DEC_PREALLOC
  66 #       define XZ_DEC_DYNALLOC
  67 #endif
  68
  69 /*
  70  * The DEC_IS_foo(mode) macros are used in "if" statements. If only some
  71  * of the supported modes are enabled, these macros will evaluate to true or
  72  * false at compile time and thus allow the compiler to omit unneeded code.
  73  */
  74 #ifdef XZ_DEC_SINGLE
  75 #       define DEC_IS_SINGLE(mode) ((mode) == XZ_SINGLE)
  76 #else
  77 #       define DEC_IS_SINGLE(mode) (false)
  78 #endif
  79
  80 #ifdef XZ_DEC_PREALLOC
  81 #       define DEC_IS_PREALLOC(mode) ((mode) == XZ_PREALLOC)
  82 #else
  83 #       define DEC_IS_PREALLOC(mode) (false)
  84 #endif
  85
  86 #ifdef XZ_DEC_DYNALLOC
  87 #       define DEC_IS_DYNALLOC(mode) ((mode) == XZ_DYNALLOC)
  88 #else
  89 #       define DEC_IS_DYNALLOC(mode) (false)
  90 #endif
  91
  92 #if !defined(XZ_DEC_SINGLE)
  93 #       define DEC_IS_MULTI(mode) (true)
  94 #elif defined(XZ_DEC_PREALLOC) || defined(XZ_DEC_DYNALLOC)
  95 #       define DEC_IS_MULTI(mode) ((mode) != XZ_SINGLE)
  96 #else
  97 #       define DEC_IS_MULTI(mode) (false)
  98 #endif
  99
 100 /*
 101  * If any of the BCJ filter decoders are wanted, define XZ_DEC_BCJ.
 102  * XZ_DEC_BCJ is used to enable generic support for BCJ decoders.
 103  */
 104 #ifndef XZ_DEC_BCJ
 105 #       if defined(XZ_DEC_X86) || defined(XZ_DEC_POWERPC) \
 106                         || defined(XZ_DEC_IA64) \
 107                         || defined(XZ_DEC_ARM) || defined(XZ_DEC_ARMTHUMB) \
 108                         || defined(XZ_DEC_SPARC) || defined(XZ_DEC_ARM64) \
 109                         || defined(XZ_DEC_RISCV)
 110 #               define XZ_DEC_BCJ
 111 #       endif
 112 #endif
 113
 114 /*
 115  * Allocate memory for LZMA2 decoder. xz_dec_lzma2_reset() must be used
 116  * before calling xz_dec_lzma2_run().
 117  */
 118 struct xz_dec_lzma2 *xz_dec_lzma2_create(enum xz_mode mode, uint32_t dict_max);
 119
 120 /*
 121  * Decode the LZMA2 properties (one byte) and reset the decoder. Return
 122  * XZ_OK on success, XZ_MEMLIMIT_ERROR if the preallocated dictionary is not
 123  * big enough, and XZ_OPTIONS_ERROR if props indicates something that this
 124  * decoder doesn't support.
 125  */
 126 enum xz_ret xz_dec_lzma2_reset(struct xz_dec_lzma2 *s, uint8_t props);
 127
 128 /* Decode raw LZMA2 stream from b->in to b->out. */
 129 enum xz_ret xz_dec_lzma2_run(struct xz_dec_lzma2 *s, struct xz_buf *b);
 130
 131 /* Free the memory allocated for the LZMA2 decoder. */
 132 void xz_dec_lzma2_end(struct xz_dec_lzma2 *s);
 133
 134 #ifdef XZ_DEC_BCJ
 135 /*
 136  * Allocate memory for BCJ decoders. xz_dec_bcj_reset() must be used before
 137  * calling xz_dec_bcj_run().
 138  */
 139 struct xz_dec_bcj *xz_dec_bcj_create(bool single_call);
 140
 141 /*
 142  * Decode the Filter ID of a BCJ filter. This implementation doesn't
 143  * support custom start offsets, so no decoding of Filter Properties
 144  * is needed. Returns XZ_OK if the given Filter ID is supported.
 145  * Otherwise XZ_OPTIONS_ERROR is returned.
 146  */
 147 enum xz_ret xz_dec_bcj_reset(struct xz_dec_bcj *s, uint8_t id);
 148
 149 /*
 150  * Decode raw BCJ + LZMA2 stream. This must be used only if there actually is
 151  * a BCJ filter in the chain. If the chain has only LZMA2, xz_dec_lzma2_run()
 152  * must be called directly.
 153  */
 154 enum xz_ret xz_dec_bcj_run(struct xz_dec_bcj *s, struct xz_dec_lzma2 *lzma2,
 155                            struct xz_buf *b);
 156
 157 /* Free the memory allocated for the BCJ filters. */
 158 #define xz_dec_bcj_end(s) kfree(s)
 159 #endif
 160
 161 #endif