grub-savannah-mirror/grub-core/lib/xzembed/xz_private.h

/* xz_private.h - Private includes and definitions */
/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 2010  Free Software Foundation, Inc.
 *
 *  GRUB is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  GRUB is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
 */
/*
 * This file is based on code from XZ embedded project
 * http://tukaani.org/xz/embedded.html
 */

#ifndef XZ_PRIVATE_H
#define XZ_PRIVATE_H

/*
 * For userspace builds, use a separate header to define the required
 * macros and functions. This makes it easier to adapt the code into
 * different environments and avoids clutter in the Linux kernel tree.
 */
#include "xz_config.h"

/*
 * If any of the BCJ filter decoders are wanted, define XZ_DEC_BCJ.
 * XZ_DEC_BCJ is used to enable generic support for BCJ decoders.
 */
#ifndef XZ_DEC_BCJ
#	if defined(XZ_DEC_X86) || defined(XZ_DEC_POWERPC) \
			|| defined(XZ_DEC_IA64) || defined(XZ_DEC_ARM) \
			|| defined(XZ_DEC_ARM) || defined(XZ_DEC_ARMTHUMB) \
			|| defined(XZ_DEC_SPARC)
#		define XZ_DEC_BCJ
#	endif
#endif

/*
 * Allocate memory for LZMA2 decoder. xz_dec_lzma2_reset() must be used
 * before calling xz_dec_lzma2_run().
 */
struct xz_dec_lzma2 * xz_dec_lzma2_create(
		uint32_t dict_max);

/*
 * Decode the LZMA2 properties (one byte) and reset the decoder. Return
 * XZ_OK on success, XZ_MEMLIMIT_ERROR if the preallocated dictionary is not
 * big enough, and XZ_OPTIONS_ERROR if props indicates something that this
 * decoder doesn't support.
 */
enum xz_ret xz_dec_lzma2_reset(
		struct xz_dec_lzma2 *s, uint8_t props);

/* Decode raw LZMA2 stream from b->in to b->out. */
enum xz_ret xz_dec_lzma2_run(
		struct xz_dec_lzma2 *s, struct xz_buf *b);

/* Free the memory allocated for the LZMA2 decoder. */
void xz_dec_lzma2_end(struct xz_dec_lzma2 *s);

/*
 * Allocate memory for BCJ decoders. xz_dec_bcj_reset() must be used before
 * calling xz_dec_bcj_run().
 */
struct xz_dec_bcj * xz_dec_bcj_create(bool single_call);

/*
 * Decode the Filter ID of a BCJ filter. This implementation doesn't
 * support custom start offsets, so no decoding of Filter Properties
 * is needed. Returns XZ_OK if the given Filter ID is supported.
 * Otherwise XZ_OPTIONS_ERROR is returned.
 */
enum xz_ret xz_dec_bcj_reset(
		struct xz_dec_bcj *s, uint8_t id);

/*
 * Decode raw BCJ + LZMA2 stream. This must be used only if there actually is
 * a BCJ filter in the chain. If the chain has only LZMA2, xz_dec_lzma2_run()
 * must be called directly.
 */
enum xz_ret xz_dec_bcj_run(struct xz_dec_bcj *s,
		struct xz_dec_lzma2 *lzma2, struct xz_buf *b);

/* Free the memory allocated for the BCJ filters. */
#define xz_dec_bcj_end(s) kfree(s)

#endif