jpayne@69: /* SPDX-License-Identifier: 0BSD */
jpayne@69: 
jpayne@69: /**
jpayne@69:  * \file        lzma/lzma12.h
jpayne@69:  * \brief       LZMA1 and LZMA2 filters
jpayne@69:  * \note        Never include this file directly. Use <lzma.h> instead.
jpayne@69:  */
jpayne@69: 
jpayne@69: /*
jpayne@69:  * Author: Lasse Collin
jpayne@69:  */
jpayne@69: 
jpayne@69: #ifndef LZMA_H_INTERNAL
jpayne@69: #	error Never include this file directly. Use <lzma.h> instead.
jpayne@69: #endif
jpayne@69: 
jpayne@69: 
jpayne@69: /**
jpayne@69:  * \brief       LZMA1 Filter ID (for raw encoder/decoder only, not in .xz)
jpayne@69:  *
jpayne@69:  * LZMA1 is the very same thing as what was called just LZMA in LZMA Utils,
jpayne@69:  * 7-Zip, and LZMA SDK. It's called LZMA1 here to prevent developers from
jpayne@69:  * accidentally using LZMA when they actually want LZMA2.
jpayne@69:  */
jpayne@69: #define LZMA_FILTER_LZMA1       LZMA_VLI_C(0x4000000000000001)
jpayne@69: 
jpayne@69: /**
jpayne@69:  * \brief       LZMA1 Filter ID with extended options (for raw encoder/decoder)
jpayne@69:  *
jpayne@69:  * This is like LZMA_FILTER_LZMA1 but with this ID a few extra options
jpayne@69:  * are supported in the lzma_options_lzma structure:
jpayne@69:  *
jpayne@69:  *   - A flag to tell the encoder if the end of payload marker (EOPM) alias
jpayne@69:  *     end of stream (EOS) marker must be written at the end of the stream.
jpayne@69:  *     In contrast, LZMA_FILTER_LZMA1 always writes the end marker.
jpayne@69:  *
jpayne@69:  *   - Decoder needs to be told the uncompressed size of the stream
jpayne@69:  *     or that it is unknown (using the special value UINT64_MAX).
jpayne@69:  *     If the size is known, a flag can be set to allow the presence of
jpayne@69:  *     the end marker anyway. In contrast, LZMA_FILTER_LZMA1 always
jpayne@69:  *     behaves as if the uncompressed size was unknown.
jpayne@69:  *
jpayne@69:  * This allows handling file formats where LZMA1 streams are used but where
jpayne@69:  * the end marker isn't allowed or where it might not (always) be present.
jpayne@69:  * This extended LZMA1 functionality is provided as a Filter ID for raw
jpayne@69:  * encoder and decoder instead of adding new encoder and decoder initialization
jpayne@69:  * functions because this way it is possible to also use extra filters,
jpayne@69:  * for example, LZMA_FILTER_X86 in a filter chain with LZMA_FILTER_LZMA1EXT,
jpayne@69:  * which might be needed to handle some file formats.
jpayne@69:  */
jpayne@69: #define LZMA_FILTER_LZMA1EXT    LZMA_VLI_C(0x4000000000000002)
jpayne@69: 
jpayne@69: /**
jpayne@69:  * \brief       LZMA2 Filter ID
jpayne@69:  *
jpayne@69:  * Usually you want this instead of LZMA1. Compared to LZMA1, LZMA2 adds
jpayne@69:  * support for LZMA_SYNC_FLUSH, uncompressed chunks (smaller expansion
jpayne@69:  * when trying to compress incompressible data), possibility to change
jpayne@69:  * lc/lp/pb in the middle of encoding, and some other internal improvements.
jpayne@69:  */
jpayne@69: #define LZMA_FILTER_LZMA2       LZMA_VLI_C(0x21)
jpayne@69: 
jpayne@69: 
jpayne@69: /**
jpayne@69:  * \brief       Match finders
jpayne@69:  *
jpayne@69:  * Match finder has major effect on both speed and compression ratio.
jpayne@69:  * Usually hash chains are faster than binary trees.
jpayne@69:  *
jpayne@69:  * If you will use LZMA_SYNC_FLUSH often, the hash chains may be a better
jpayne@69:  * choice, because binary trees get much higher compression ratio penalty
jpayne@69:  * with LZMA_SYNC_FLUSH.
jpayne@69:  *
jpayne@69:  * The memory usage formulas are only rough estimates, which are closest to
jpayne@69:  * reality when dict_size is a power of two. The formulas are  more complex
jpayne@69:  * in reality, and can also change a little between liblzma versions. Use
jpayne@69:  * lzma_raw_encoder_memusage() to get more accurate estimate of memory usage.
jpayne@69:  */
jpayne@69: typedef enum {
jpayne@69: 	LZMA_MF_HC3     = 0x03,
jpayne@69: 		/**<
jpayne@69: 		 * \brief       Hash Chain with 2- and 3-byte hashing
jpayne@69: 		 *
jpayne@69: 		 * Minimum nice_len: 3
jpayne@69: 		 *
jpayne@69: 		 * Memory usage:
jpayne@69: 		 *  - dict_size <= 16 MiB: dict_size * 7.5
jpayne@69: 		 *  - dict_size > 16 MiB: dict_size * 5.5 + 64 MiB
jpayne@69: 		 */
jpayne@69: 
jpayne@69: 	LZMA_MF_HC4     = 0x04,
jpayne@69: 		/**<
jpayne@69: 		 * \brief       Hash Chain with 2-, 3-, and 4-byte hashing
jpayne@69: 		 *
jpayne@69: 		 * Minimum nice_len: 4
jpayne@69: 		 *
jpayne@69: 		 * Memory usage:
jpayne@69: 		 *  - dict_size <= 32 MiB: dict_size * 7.5
jpayne@69: 		 *  - dict_size > 32 MiB: dict_size * 6.5
jpayne@69: 		 */
jpayne@69: 
jpayne@69: 	LZMA_MF_BT2     = 0x12,
jpayne@69: 		/**<
jpayne@69: 		 * \brief       Binary Tree with 2-byte hashing
jpayne@69: 		 *
jpayne@69: 		 * Minimum nice_len: 2
jpayne@69: 		 *
jpayne@69: 		 * Memory usage: dict_size * 9.5
jpayne@69: 		 */
jpayne@69: 
jpayne@69: 	LZMA_MF_BT3     = 0x13,
jpayne@69: 		/**<
jpayne@69: 		 * \brief       Binary Tree with 2- and 3-byte hashing
jpayne@69: 		 *
jpayne@69: 		 * Minimum nice_len: 3
jpayne@69: 		 *
jpayne@69: 		 * Memory usage:
jpayne@69: 		 *  - dict_size <= 16 MiB: dict_size * 11.5
jpayne@69: 		 *  - dict_size > 16 MiB: dict_size * 9.5 + 64 MiB
jpayne@69: 		 */
jpayne@69: 
jpayne@69: 	LZMA_MF_BT4     = 0x14
jpayne@69: 		/**<
jpayne@69: 		 * \brief       Binary Tree with 2-, 3-, and 4-byte hashing
jpayne@69: 		 *
jpayne@69: 		 * Minimum nice_len: 4
jpayne@69: 		 *
jpayne@69: 		 * Memory usage:
jpayne@69: 		 *  - dict_size <= 32 MiB: dict_size * 11.5
jpayne@69: 		 *  - dict_size > 32 MiB: dict_size * 10.5
jpayne@69: 		 */
jpayne@69: } lzma_match_finder;
jpayne@69: 
jpayne@69: 
jpayne@69: /**
jpayne@69:  * \brief       Test if given match finder is supported
jpayne@69:  *
jpayne@69:  * It is safe to call this with a value that isn't listed in
jpayne@69:  * lzma_match_finder enumeration; the return value will be false.
jpayne@69:  *
jpayne@69:  * There is no way to list which match finders are available in this
jpayne@69:  * particular liblzma version and build. It would be useless, because
jpayne@69:  * a new match finder, which the application developer wasn't aware,
jpayne@69:  * could require giving additional options to the encoder that the older
jpayne@69:  * match finders don't need.
jpayne@69:  *
jpayne@69:  * \param       match_finder    Match finder ID
jpayne@69:  *
jpayne@69:  * \return      lzma_bool:
jpayne@69:  *              - true if the match finder is supported by this liblzma build.
jpayne@69:  *              - false otherwise.
jpayne@69:  */
jpayne@69: extern LZMA_API(lzma_bool) lzma_mf_is_supported(lzma_match_finder match_finder)
jpayne@69: 		lzma_nothrow lzma_attr_const;
jpayne@69: 
jpayne@69: 
jpayne@69: /**
jpayne@69:  * \brief       Compression modes
jpayne@69:  *
jpayne@69:  * This selects the function used to analyze the data produced by the match
jpayne@69:  * finder.
jpayne@69:  */
jpayne@69: typedef enum {
jpayne@69: 	LZMA_MODE_FAST = 1,
jpayne@69: 		/**<
jpayne@69: 		 * \brief       Fast compression
jpayne@69: 		 *
jpayne@69: 		 * Fast mode is usually at its best when combined with
jpayne@69: 		 * a hash chain match finder.
jpayne@69: 		 */
jpayne@69: 
jpayne@69: 	LZMA_MODE_NORMAL = 2
jpayne@69: 		/**<
jpayne@69: 		 * \brief       Normal compression
jpayne@69: 		 *
jpayne@69: 		 * This is usually notably slower than fast mode. Use this
jpayne@69: 		 * together with binary tree match finders to expose the
jpayne@69: 		 * full potential of the LZMA1 or LZMA2 encoder.
jpayne@69: 		 */
jpayne@69: } lzma_mode;
jpayne@69: 
jpayne@69: 
jpayne@69: /**
jpayne@69:  * \brief       Test if given compression mode is supported
jpayne@69:  *
jpayne@69:  * It is safe to call this with a value that isn't listed in lzma_mode
jpayne@69:  * enumeration; the return value will be false.
jpayne@69:  *
jpayne@69:  * There is no way to list which modes are available in this particular
jpayne@69:  * liblzma version and build. It would be useless, because a new compression
jpayne@69:  * mode, which the application developer wasn't aware, could require giving
jpayne@69:  * additional options to the encoder that the older modes don't need.
jpayne@69:  *
jpayne@69:  * \param       mode    Mode ID.
jpayne@69:  *
jpayne@69:  * \return      lzma_bool:
jpayne@69:  *              - true if the compression mode is supported by this liblzma
jpayne@69:  *                build.
jpayne@69:  *              - false otherwise.
jpayne@69:  */
jpayne@69: extern LZMA_API(lzma_bool) lzma_mode_is_supported(lzma_mode mode)
jpayne@69: 		lzma_nothrow lzma_attr_const;
jpayne@69: 
jpayne@69: 
jpayne@69: /**
jpayne@69:  * \brief       Options specific to the LZMA1 and LZMA2 filters
jpayne@69:  *
jpayne@69:  * Since LZMA1 and LZMA2 share most of the code, it's simplest to share
jpayne@69:  * the options structure too. For encoding, all but the reserved variables
jpayne@69:  * need to be initialized unless specifically mentioned otherwise.
jpayne@69:  * lzma_lzma_preset() can be used to get a good starting point.
jpayne@69:  *
jpayne@69:  * For raw decoding, both LZMA1 and LZMA2 need dict_size, preset_dict, and
jpayne@69:  * preset_dict_size (if preset_dict != NULL). LZMA1 needs also lc, lp, and pb.
jpayne@69:  */
jpayne@69: typedef struct {
jpayne@69: 	/**
jpayne@69: 	 * \brief       Dictionary size in bytes
jpayne@69: 	 *
jpayne@69: 	 * Dictionary size indicates how many bytes of the recently processed
jpayne@69: 	 * uncompressed data is kept in memory. One method to reduce size of
jpayne@69: 	 * the uncompressed data is to store distance-length pairs, which
jpayne@69: 	 * indicate what data to repeat from the dictionary buffer. Thus,
jpayne@69: 	 * the bigger the dictionary, the better the compression ratio
jpayne@69: 	 * usually is.
jpayne@69: 	 *
jpayne@69: 	 * Maximum size of the dictionary depends on multiple things:
jpayne@69: 	 *  - Memory usage limit
jpayne@69: 	 *  - Available address space (not a problem on 64-bit systems)
jpayne@69: 	 *  - Selected match finder (encoder only)
jpayne@69: 	 *
jpayne@69: 	 * Currently the maximum dictionary size for encoding is 1.5 GiB
jpayne@69: 	 * (i.e. (UINT32_C(1) << 30) + (UINT32_C(1) << 29)) even on 64-bit
jpayne@69: 	 * systems for certain match finder implementation reasons. In the
jpayne@69: 	 * future, there may be match finders that support bigger
jpayne@69: 	 * dictionaries.
jpayne@69: 	 *
jpayne@69: 	 * Decoder already supports dictionaries up to 4 GiB - 1 B (i.e.
jpayne@69: 	 * UINT32_MAX), so increasing the maximum dictionary size of the
jpayne@69: 	 * encoder won't cause problems for old decoders.
jpayne@69: 	 *
jpayne@69: 	 * Because extremely small dictionaries sizes would have unneeded
jpayne@69: 	 * overhead in the decoder, the minimum dictionary size is 4096 bytes.
jpayne@69: 	 *
jpayne@69: 	 * \note        When decoding, too big dictionary does no other harm
jpayne@69: 	 *              than wasting memory.
jpayne@69: 	 */
jpayne@69: 	uint32_t dict_size;
jpayne@69: #	define LZMA_DICT_SIZE_MIN       UINT32_C(4096)
jpayne@69: #	define LZMA_DICT_SIZE_DEFAULT   (UINT32_C(1) << 23)
jpayne@69: 
jpayne@69: 	/**
jpayne@69: 	 * \brief       Pointer to an initial dictionary
jpayne@69: 	 *
jpayne@69: 	 * It is possible to initialize the LZ77 history window using
jpayne@69: 	 * a preset dictionary. It is useful when compressing many
jpayne@69: 	 * similar, relatively small chunks of data independently from
jpayne@69: 	 * each other. The preset dictionary should contain typical
jpayne@69: 	 * strings that occur in the files being compressed. The most
jpayne@69: 	 * probable strings should be near the end of the preset dictionary.
jpayne@69: 	 *
jpayne@69: 	 * This feature should be used only in special situations. For
jpayne@69: 	 * now, it works correctly only with raw encoding and decoding.
jpayne@69: 	 * Currently none of the container formats supported by
jpayne@69: 	 * liblzma allow preset dictionary when decoding, thus if
jpayne@69: 	 * you create a .xz or .lzma file with preset dictionary, it
jpayne@69: 	 * cannot be decoded with the regular decoder functions. In the
jpayne@69: 	 * future, the .xz format will likely get support for preset
jpayne@69: 	 * dictionary though.
jpayne@69: 	 */
jpayne@69: 	const uint8_t *preset_dict;
jpayne@69: 
jpayne@69: 	/**
jpayne@69: 	 * \brief       Size of the preset dictionary
jpayne@69: 	 *
jpayne@69: 	 * Specifies the size of the preset dictionary. If the size is
jpayne@69: 	 * bigger than dict_size, only the last dict_size bytes are
jpayne@69: 	 * processed.
jpayne@69: 	 *
jpayne@69: 	 * This variable is read only when preset_dict is not NULL.
jpayne@69: 	 * If preset_dict is not NULL but preset_dict_size is zero,
jpayne@69: 	 * no preset dictionary is used (identical to only setting
jpayne@69: 	 * preset_dict to NULL).
jpayne@69: 	 */
jpayne@69: 	uint32_t preset_dict_size;
jpayne@69: 
jpayne@69: 	/**
jpayne@69: 	 * \brief       Number of literal context bits
jpayne@69: 	 *
jpayne@69: 	 * How many of the highest bits of the previous uncompressed
jpayne@69: 	 * eight-bit byte (also known as 'literal') are taken into
jpayne@69: 	 * account when predicting the bits of the next literal.
jpayne@69: 	 *
jpayne@69: 	 * E.g. in typical English text, an upper-case letter is
jpayne@69: 	 * often followed by a lower-case letter, and a lower-case
jpayne@69: 	 * letter is usually followed by another lower-case letter.
jpayne@69: 	 * In the US-ASCII character set, the highest three bits are 010
jpayne@69: 	 * for upper-case letters and 011 for lower-case letters.
jpayne@69: 	 * When lc is at least 3, the literal coding can take advantage of
jpayne@69: 	 * this property in the uncompressed data.
jpayne@69: 	 *
jpayne@69: 	 * There is a limit that applies to literal context bits and literal
jpayne@69: 	 * position bits together: lc + lp <= 4. Without this limit the
jpayne@69: 	 * decoding could become very slow, which could have security related
jpayne@69: 	 * results in some cases like email servers doing virus scanning.
jpayne@69: 	 * This limit also simplifies the internal implementation in liblzma.
jpayne@69: 	 *
jpayne@69: 	 * There may be LZMA1 streams that have lc + lp > 4 (maximum possible
jpayne@69: 	 * lc would be 8). It is not possible to decode such streams with
jpayne@69: 	 * liblzma.
jpayne@69: 	 */
jpayne@69: 	uint32_t lc;
jpayne@69: #	define LZMA_LCLP_MIN    0
jpayne@69: #	define LZMA_LCLP_MAX    4
jpayne@69: #	define LZMA_LC_DEFAULT  3
jpayne@69: 
jpayne@69: 	/**
jpayne@69: 	 * \brief       Number of literal position bits
jpayne@69: 	 *
jpayne@69: 	 * lp affects what kind of alignment in the uncompressed data is
jpayne@69: 	 * assumed when encoding literals. A literal is a single 8-bit byte.
jpayne@69: 	 * See pb below for more information about alignment.
jpayne@69: 	 */
jpayne@69: 	uint32_t lp;
jpayne@69: #	define LZMA_LP_DEFAULT  0
jpayne@69: 
jpayne@69: 	/**
jpayne@69: 	 * \brief       Number of position bits
jpayne@69: 	 *
jpayne@69: 	 * pb affects what kind of alignment in the uncompressed data is
jpayne@69: 	 * assumed in general. The default means four-byte alignment
jpayne@69: 	 * (2^ pb =2^2=4), which is often a good choice when there's
jpayne@69: 	 * no better guess.
jpayne@69: 	 *
jpayne@69: 	 * When the alignment is known, setting pb accordingly may reduce
jpayne@69: 	 * the file size a little. E.g. with text files having one-byte
jpayne@69: 	 * alignment (US-ASCII, ISO-8859-*, UTF-8), setting pb=0 can
jpayne@69: 	 * improve compression slightly. For UTF-16 text, pb=1 is a good
jpayne@69: 	 * choice. If the alignment is an odd number like 3 bytes, pb=0
jpayne@69: 	 * might be the best choice.
jpayne@69: 	 *
jpayne@69: 	 * Even though the assumed alignment can be adjusted with pb and
jpayne@69: 	 * lp, LZMA1 and LZMA2 still slightly favor 16-byte alignment.
jpayne@69: 	 * It might be worth taking into account when designing file formats
jpayne@69: 	 * that are likely to be often compressed with LZMA1 or LZMA2.
jpayne@69: 	 */
jpayne@69: 	uint32_t pb;
jpayne@69: #	define LZMA_PB_MIN      0
jpayne@69: #	define LZMA_PB_MAX      4
jpayne@69: #	define LZMA_PB_DEFAULT  2
jpayne@69: 
jpayne@69: 	/** Compression mode */
jpayne@69: 	lzma_mode mode;
jpayne@69: 
jpayne@69: 	/**
jpayne@69: 	 * \brief       Nice length of a match
jpayne@69: 	 *
jpayne@69: 	 * This determines how many bytes the encoder compares from the match
jpayne@69: 	 * candidates when looking for the best match. Once a match of at
jpayne@69: 	 * least nice_len bytes long is found, the encoder stops looking for
jpayne@69: 	 * better candidates and encodes the match. (Naturally, if the found
jpayne@69: 	 * match is actually longer than nice_len, the actual length is
jpayne@69: 	 * encoded; it's not truncated to nice_len.)
jpayne@69: 	 *
jpayne@69: 	 * Bigger values usually increase the compression ratio and
jpayne@69: 	 * compression time. For most files, 32 to 128 is a good value,
jpayne@69: 	 * which gives very good compression ratio at good speed.
jpayne@69: 	 *
jpayne@69: 	 * The exact minimum value depends on the match finder. The maximum
jpayne@69: 	 * is 273, which is the maximum length of a match that LZMA1 and
jpayne@69: 	 * LZMA2 can encode.
jpayne@69: 	 */
jpayne@69: 	uint32_t nice_len;
jpayne@69: 
jpayne@69: 	/** Match finder ID */
jpayne@69: 	lzma_match_finder mf;
jpayne@69: 
jpayne@69: 	/**
jpayne@69: 	 * \brief       Maximum search depth in the match finder
jpayne@69: 	 *
jpayne@69: 	 * For every input byte, match finder searches through the hash chain
jpayne@69: 	 * or binary tree in a loop, each iteration going one step deeper in
jpayne@69: 	 * the chain or tree. The searching stops if
jpayne@69: 	 *  - a match of at least nice_len bytes long is found;
jpayne@69: 	 *  - all match candidates from the hash chain or binary tree have
jpayne@69: 	 *    been checked; or
jpayne@69: 	 *  - maximum search depth is reached.
jpayne@69: 	 *
jpayne@69: 	 * Maximum search depth is needed to prevent the match finder from
jpayne@69: 	 * wasting too much time in case there are lots of short match
jpayne@69: 	 * candidates. On the other hand, stopping the search before all
jpayne@69: 	 * candidates have been checked can reduce compression ratio.
jpayne@69: 	 *
jpayne@69: 	 * Setting depth to zero tells liblzma to use an automatic default
jpayne@69: 	 * value, that depends on the selected match finder and nice_len.
jpayne@69: 	 * The default is in the range [4, 200] or so (it may vary between
jpayne@69: 	 * liblzma versions).
jpayne@69: 	 *
jpayne@69: 	 * Using a bigger depth value than the default can increase
jpayne@69: 	 * compression ratio in some cases. There is no strict maximum value,
jpayne@69: 	 * but high values (thousands or millions) should be used with care:
jpayne@69: 	 * the encoder could remain fast enough with typical input, but
jpayne@69: 	 * malicious input could cause the match finder to slow down
jpayne@69: 	 * dramatically, possibly creating a denial of service attack.
jpayne@69: 	 */
jpayne@69: 	uint32_t depth;
jpayne@69: 
jpayne@69: 	/**
jpayne@69: 	 * \brief       For LZMA_FILTER_LZMA1EXT: Extended flags
jpayne@69: 	 *
jpayne@69: 	 * This is used only with LZMA_FILTER_LZMA1EXT.
jpayne@69: 	 *
jpayne@69: 	 * Currently only one flag is supported, LZMA_LZMA1EXT_ALLOW_EOPM:
jpayne@69: 	 *
jpayne@69: 	 *   - Encoder: If the flag is set, then end marker is written just
jpayne@69: 	 *     like it is with LZMA_FILTER_LZMA1. Without this flag the
jpayne@69: 	 *     end marker isn't written and the application has to store
jpayne@69: 	 *     the uncompressed size somewhere outside the compressed stream.
jpayne@69: 	 *     To decompress streams without the end marker, the application
jpayne@69: 	 *     has to set the correct uncompressed size in ext_size_low and
jpayne@69: 	 *     ext_size_high.
jpayne@69: 	 *
jpayne@69: 	 *   - Decoder: If the uncompressed size in ext_size_low and
jpayne@69: 	 *     ext_size_high is set to the special value UINT64_MAX
jpayne@69: 	 *     (indicating unknown uncompressed size) then this flag is
jpayne@69: 	 *     ignored and the end marker must always be present, that is,
jpayne@69: 	 *     the behavior is identical to LZMA_FILTER_LZMA1.
jpayne@69: 	 *
jpayne@69: 	 *     Otherwise, if this flag isn't set, then the input stream
jpayne@69: 	 *     must not have the end marker; if the end marker is detected
jpayne@69: 	 *     then it will result in LZMA_DATA_ERROR. This is useful when
jpayne@69: 	 *     it is known that the stream must not have the end marker and
jpayne@69: 	 *     strict validation is wanted.
jpayne@69: 	 *
jpayne@69: 	 *     If this flag is set, then it is autodetected if the end marker
jpayne@69: 	 *     is present after the specified number of uncompressed bytes
jpayne@69: 	 *     has been decompressed (ext_size_low and ext_size_high). The
jpayne@69: 	 *     end marker isn't allowed in any other position. This behavior
jpayne@69: 	 *     is useful when uncompressed size is known but the end marker
jpayne@69: 	 *     may or may not be present. This is the case, for example,
jpayne@69: 	 *     in .7z files (valid .7z files that have the end marker in
jpayne@69: 	 *     LZMA1 streams are rare but they do exist).
jpayne@69: 	 */
jpayne@69: 	uint32_t ext_flags;
jpayne@69: #	define LZMA_LZMA1EXT_ALLOW_EOPM   UINT32_C(0x01)
jpayne@69: 
jpayne@69: 	/**
jpayne@69: 	 * \brief       For LZMA_FILTER_LZMA1EXT: Uncompressed size (low bits)
jpayne@69: 	 *
jpayne@69: 	 * The 64-bit uncompressed size is needed for decompression with
jpayne@69: 	 * LZMA_FILTER_LZMA1EXT. The size is ignored by the encoder.
jpayne@69: 	 *
jpayne@69: 	 * The special value UINT64_MAX indicates that the uncompressed size
jpayne@69: 	 * is unknown and that the end of payload marker (also known as
jpayne@69: 	 * end of stream marker) must be present to indicate the end of
jpayne@69: 	 * the LZMA1 stream. Any other value indicates the expected
jpayne@69: 	 * uncompressed size of the LZMA1 stream. (If LZMA1 was used together
jpayne@69: 	 * with filters that change the size of the data then the uncompressed
jpayne@69: 	 * size of the LZMA1 stream could be different than the final
jpayne@69: 	 * uncompressed size of the filtered stream.)
jpayne@69: 	 *
jpayne@69: 	 * ext_size_low holds the least significant 32 bits of the
jpayne@69: 	 * uncompressed size. The most significant 32 bits must be set
jpayne@69: 	 * in ext_size_high. The macro lzma_set_ext_size(opt_lzma, u64size)
jpayne@69: 	 * can be used to set these members.
jpayne@69: 	 *
jpayne@69: 	 * The 64-bit uncompressed size is split into two uint32_t variables
jpayne@69: 	 * because there were no reserved uint64_t members and using the
jpayne@69: 	 * same options structure for LZMA_FILTER_LZMA1, LZMA_FILTER_LZMA1EXT,
jpayne@69: 	 * and LZMA_FILTER_LZMA2 was otherwise more convenient than having
jpayne@69: 	 * a new options structure for LZMA_FILTER_LZMA1EXT. (Replacing two
jpayne@69: 	 * uint32_t members with one uint64_t changes the ABI on some systems
jpayne@69: 	 * as the alignment of this struct can increase from 4 bytes to 8.)
jpayne@69: 	 */
jpayne@69: 	uint32_t ext_size_low;
jpayne@69: 
jpayne@69: 	/**
jpayne@69: 	 * \brief       For LZMA_FILTER_LZMA1EXT: Uncompressed size (high bits)
jpayne@69: 	 *
jpayne@69: 	 * This holds the most significant 32 bits of the uncompressed size.
jpayne@69: 	 */
jpayne@69: 	uint32_t ext_size_high;
jpayne@69: 
jpayne@69: 	/*
jpayne@69: 	 * Reserved space to allow possible future extensions without
jpayne@69: 	 * breaking the ABI. You should not touch these, because the names
jpayne@69: 	 * of these variables may change. These are and will never be used
jpayne@69: 	 * with the currently supported options, so it is safe to leave these
jpayne@69: 	 * uninitialized.
jpayne@69: 	 */
jpayne@69: 
jpayne@69: 	/** \private     Reserved member. */
jpayne@69: 	uint32_t reserved_int4;
jpayne@69: 
jpayne@69: 	/** \private     Reserved member. */
jpayne@69: 	uint32_t reserved_int5;
jpayne@69: 
jpayne@69: 	/** \private     Reserved member. */
jpayne@69: 	uint32_t reserved_int6;
jpayne@69: 
jpayne@69: 	/** \private     Reserved member. */
jpayne@69: 	uint32_t reserved_int7;
jpayne@69: 
jpayne@69: 	/** \private     Reserved member. */
jpayne@69: 	uint32_t reserved_int8;
jpayne@69: 
jpayne@69: 	/** \private     Reserved member. */
jpayne@69: 	lzma_reserved_enum reserved_enum1;
jpayne@69: 
jpayne@69: 	/** \private     Reserved member. */
jpayne@69: 	lzma_reserved_enum reserved_enum2;
jpayne@69: 
jpayne@69: 	/** \private     Reserved member. */
jpayne@69: 	lzma_reserved_enum reserved_enum3;
jpayne@69: 
jpayne@69: 	/** \private     Reserved member. */
jpayne@69: 	lzma_reserved_enum reserved_enum4;
jpayne@69: 
jpayne@69: 	/** \private     Reserved member. */
jpayne@69: 	void *reserved_ptr1;
jpayne@69: 
jpayne@69: 	/** \private     Reserved member. */
jpayne@69: 	void *reserved_ptr2;
jpayne@69: 
jpayne@69: } lzma_options_lzma;
jpayne@69: 
jpayne@69: 
jpayne@69: /**
jpayne@69:  * \brief       Macro to set the 64-bit uncompressed size in ext_size_*
jpayne@69:  *
jpayne@69:  * This might be convenient when decoding using LZMA_FILTER_LZMA1EXT.
jpayne@69:  * This isn't used with LZMA_FILTER_LZMA1 or LZMA_FILTER_LZMA2.
jpayne@69:  */
jpayne@69: #define lzma_set_ext_size(opt_lzma2, u64size) \
jpayne@69: do { \
jpayne@69: 	(opt_lzma2).ext_size_low = (uint32_t)(u64size); \
jpayne@69: 	(opt_lzma2).ext_size_high = (uint32_t)((uint64_t)(u64size) >> 32); \
jpayne@69: } while (0)
jpayne@69: 
jpayne@69: 
jpayne@69: /**
jpayne@69:  * \brief       Set a compression preset to lzma_options_lzma structure
jpayne@69:  *
jpayne@69:  * 0 is the fastest and 9 is the slowest. These match the switches -0 .. -9
jpayne@69:  * of the xz command line tool. In addition, it is possible to bitwise-or
jpayne@69:  * flags to the preset. Currently only LZMA_PRESET_EXTREME is supported.
jpayne@69:  * The flags are defined in container.h, because the flags are used also
jpayne@69:  * with lzma_easy_encoder().
jpayne@69:  *
jpayne@69:  * The preset levels are subject to changes between liblzma versions.
jpayne@69:  *
jpayne@69:  * This function is available only if LZMA1 or LZMA2 encoder has been enabled
jpayne@69:  * when building liblzma.
jpayne@69:  *
jpayne@69:  * If features (like certain match finders) have been disabled at build time,
jpayne@69:  * then the function may return success (false) even though the resulting
jpayne@69:  * LZMA1/LZMA2 options may not be usable for encoder initialization
jpayne@69:  * (LZMA_OPTIONS_ERROR).
jpayne@69:  *
jpayne@69:  * \param[out]  options Pointer to LZMA1 or LZMA2 options to be filled
jpayne@69:  * \param       preset  Preset level bitwse-ORed with preset flags
jpayne@69:  *
jpayne@69:  * \return      lzma_bool:
jpayne@69:  *              - true if the preset is not supported (failure).
jpayne@69:  *              - false otherwise (success).
jpayne@69:  */
jpayne@69: extern LZMA_API(lzma_bool) lzma_lzma_preset(
jpayne@69: 		lzma_options_lzma *options, uint32_t preset) lzma_nothrow;