LXR linux/lib/xz/xz

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