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