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authorLasse Collin <lasse.collin@tukaani.org>2014-05-04 11:07:17 +0300
committerLasse Collin <lasse.collin@tukaani.org>2014-05-04 11:07:17 +0300
commit4d5b7b3fda31241ca86ed35e08e73f776ee916e0 (patch)
tree74399fadc97b8a7c2627e99ab1de3b66477e57eb /src/liblzma/api/lzma/lzma.h
parentBuild: Fix the combination of --disable-xzdec --enable-lzmadec. (diff)
downloadxz-4d5b7b3fda31241ca86ed35e08e73f776ee916e0.tar.xz
liblzma: Rename the private API header lzma/lzma.h to lzma/lzma12.h.
It can be confusing that two header files have the same name. The public API file is still lzma.h.
Diffstat (limited to 'src/liblzma/api/lzma/lzma.h')
-rw-r--r--src/liblzma/api/lzma/lzma.h420
1 files changed, 0 insertions, 420 deletions
diff --git a/src/liblzma/api/lzma/lzma.h b/src/liblzma/api/lzma/lzma.h
deleted file mode 100644
index 3f8e095f..00000000
--- a/src/liblzma/api/lzma/lzma.h
+++ /dev/null
@@ -1,420 +0,0 @@
-/**
- * \file lzma/lzma.h
- * \brief LZMA1 and LZMA2 filters
- */
-
-/*
- * Author: Lasse Collin
- *
- * This file has been put into the public domain.
- * You can do whatever you want with this file.
- *
- * See ../lzma.h for information about liblzma as a whole.
- */
-
-#ifndef LZMA_H_INTERNAL
-# error Never include this file directly. Use <lzma.h> instead.
-#endif
-
-
-/**
- * \brief LZMA1 Filter ID
- *
- * LZMA1 is the very same thing as what was called just LZMA in LZMA Utils,
- * 7-Zip, and LZMA SDK. It's called LZMA1 here to prevent developers from
- * accidentally using LZMA when they actually want LZMA2.
- *
- * LZMA1 shouldn't be used for new applications unless you _really_ know
- * what you are doing. LZMA2 is almost always a better choice.
- */
-#define LZMA_FILTER_LZMA1 LZMA_VLI_C(0x4000000000000001)
-
-/**
- * \brief LZMA2 Filter ID
- *
- * Usually you want this instead of LZMA1. Compared to LZMA1, LZMA2 adds
- * support for LZMA_SYNC_FLUSH, uncompressed chunks (smaller expansion
- * when trying to compress uncompressible data), possibility to change
- * lc/lp/pb in the middle of encoding, and some other internal improvements.
- */
-#define LZMA_FILTER_LZMA2 LZMA_VLI_C(0x21)
-
-
-/**
- * \brief Match finders
- *
- * Match finder has major effect on both speed and compression ratio.
- * Usually hash chains are faster than binary trees.
- *
- * If you will use LZMA_SYNC_FLUSH often, the hash chains may be a better
- * choice, because binary trees get much higher compression ratio penalty
- * with LZMA_SYNC_FLUSH.
- *
- * The memory usage formulas are only rough estimates, which are closest to
- * reality when dict_size is a power of two. The formulas are more complex
- * in reality, and can also change a little between liblzma versions. Use
- * lzma_raw_encoder_memusage() to get more accurate estimate of memory usage.
- */
-typedef enum {
- LZMA_MF_HC3 = 0x03,
- /**<
- * \brief Hash Chain with 2- and 3-byte hashing
- *
- * Minimum nice_len: 3
- *
- * Memory usage:
- * - dict_size <= 16 MiB: dict_size * 7.5
- * - dict_size > 16 MiB: dict_size * 5.5 + 64 MiB
- */
-
- LZMA_MF_HC4 = 0x04,
- /**<
- * \brief Hash Chain with 2-, 3-, and 4-byte hashing
- *
- * Minimum nice_len: 4
- *
- * Memory usage:
- * - dict_size <= 32 MiB: dict_size * 7.5
- * - dict_size > 32 MiB: dict_size * 6.5
- */
-
- LZMA_MF_BT2 = 0x12,
- /**<
- * \brief Binary Tree with 2-byte hashing
- *
- * Minimum nice_len: 2
- *
- * Memory usage: dict_size * 9.5
- */
-
- LZMA_MF_BT3 = 0x13,
- /**<
- * \brief Binary Tree with 2- and 3-byte hashing
- *
- * Minimum nice_len: 3
- *
- * Memory usage:
- * - dict_size <= 16 MiB: dict_size * 11.5
- * - dict_size > 16 MiB: dict_size * 9.5 + 64 MiB
- */
-
- LZMA_MF_BT4 = 0x14
- /**<
- * \brief Binary Tree with 2-, 3-, and 4-byte hashing
- *
- * Minimum nice_len: 4
- *
- * Memory usage:
- * - dict_size <= 32 MiB: dict_size * 11.5
- * - dict_size > 32 MiB: dict_size * 10.5
- */
-} lzma_match_finder;
-
-
-/**
- * \brief Test if given match finder is supported
- *
- * Return true if the given match finder is supported by this liblzma build.
- * Otherwise false is returned. It is safe to call this with a value that
- * isn't listed in lzma_match_finder enumeration; the return value will be
- * false.
- *
- * There is no way to list which match finders are available in this
- * particular liblzma version and build. It would be useless, because
- * a new match finder, which the application developer wasn't aware,
- * could require giving additional options to the encoder that the older
- * match finders don't need.
- */
-extern LZMA_API(lzma_bool) lzma_mf_is_supported(lzma_match_finder match_finder)
- lzma_nothrow lzma_attr_const;
-
-
-/**
- * \brief Compression modes
- *
- * This selects the function used to analyze the data produced by the match
- * finder.
- */
-typedef enum {
- LZMA_MODE_FAST = 1,
- /**<
- * \brief Fast compression
- *
- * Fast mode is usually at its best when combined with
- * a hash chain match finder.
- */
-
- LZMA_MODE_NORMAL = 2
- /**<
- * \brief Normal compression
- *
- * This is usually notably slower than fast mode. Use this
- * together with binary tree match finders to expose the
- * full potential of the LZMA1 or LZMA2 encoder.
- */
-} lzma_mode;
-
-
-/**
- * \brief Test if given compression mode is supported
- *
- * Return true if the given compression mode is supported by this liblzma
- * build. Otherwise false is returned. It is safe to call this with a value
- * that isn't listed in lzma_mode enumeration; the return value will be false.
- *
- * There is no way to list which modes are available in this particular
- * liblzma version and build. It would be useless, because a new compression
- * mode, which the application developer wasn't aware, could require giving
- * additional options to the encoder that the older modes don't need.
- */
-extern LZMA_API(lzma_bool) lzma_mode_is_supported(lzma_mode mode)
- lzma_nothrow lzma_attr_const;
-
-
-/**
- * \brief Options specific to the LZMA1 and LZMA2 filters
- *
- * Since LZMA1 and LZMA2 share most of the code, it's simplest to share
- * the options structure too. For encoding, all but the reserved variables
- * need to be initialized unless specifically mentioned otherwise.
- * lzma_lzma_preset() can be used to get a good starting point.
- *
- * For raw decoding, both LZMA1 and LZMA2 need dict_size, preset_dict, and
- * preset_dict_size (if preset_dict != NULL). LZMA1 needs also lc, lp, and pb.
- */
-typedef struct {
- /**
- * \brief Dictionary size in bytes
- *
- * Dictionary size indicates how many bytes of the recently processed
- * uncompressed data is kept in memory. One method to reduce size of
- * the uncompressed data is to store distance-length pairs, which
- * indicate what data to repeat from the dictionary buffer. Thus,
- * the bigger the dictionary, the better the compression ratio
- * usually is.
- *
- * Maximum size of the dictionary depends on multiple things:
- * - Memory usage limit
- * - Available address space (not a problem on 64-bit systems)
- * - Selected match finder (encoder only)
- *
- * Currently the maximum dictionary size for encoding is 1.5 GiB
- * (i.e. (UINT32_C(1) << 30) + (UINT32_C(1) << 29)) even on 64-bit
- * systems for certain match finder implementation reasons. In the
- * future, there may be match finders that support bigger
- * dictionaries.
- *
- * Decoder already supports dictionaries up to 4 GiB - 1 B (i.e.
- * UINT32_MAX), so increasing the maximum dictionary size of the
- * encoder won't cause problems for old decoders.
- *
- * Because extremely small dictionaries sizes would have unneeded
- * overhead in the decoder, the minimum dictionary size is 4096 bytes.
- *
- * \note When decoding, too big dictionary does no other harm
- * than wasting memory.
- */
- uint32_t dict_size;
-# define LZMA_DICT_SIZE_MIN UINT32_C(4096)
-# define LZMA_DICT_SIZE_DEFAULT (UINT32_C(1) << 23)
-
- /**
- * \brief Pointer to an initial dictionary
- *
- * It is possible to initialize the LZ77 history window using
- * a preset dictionary. It is useful when compressing many
- * similar, relatively small chunks of data independently from
- * each other. The preset dictionary should contain typical
- * strings that occur in the files being compressed. The most
- * probable strings should be near the end of the preset dictionary.
- *
- * This feature should be used only in special situations. For
- * now, it works correctly only with raw encoding and decoding.
- * Currently none of the container formats supported by
- * liblzma allow preset dictionary when decoding, thus if
- * you create a .xz or .lzma file with preset dictionary, it
- * cannot be decoded with the regular decoder functions. In the
- * future, the .xz format will likely get support for preset
- * dictionary though.
- */
- const uint8_t *preset_dict;
-
- /**
- * \brief Size of the preset dictionary
- *
- * Specifies the size of the preset dictionary. If the size is
- * bigger than dict_size, only the last dict_size bytes are
- * processed.
- *
- * This variable is read only when preset_dict is not NULL.
- * If preset_dict is not NULL but preset_dict_size is zero,
- * no preset dictionary is used (identical to only setting
- * preset_dict to NULL).
- */
- uint32_t preset_dict_size;
-
- /**
- * \brief Number of literal context bits
- *
- * How many of the highest bits of the previous uncompressed
- * eight-bit byte (also known as `literal') are taken into
- * account when predicting the bits of the next literal.
- *
- * E.g. in typical English text, an upper-case letter is
- * often followed by a lower-case letter, and a lower-case
- * letter is usually followed by another lower-case letter.
- * In the US-ASCII character set, the highest three bits are 010
- * for upper-case letters and 011 for lower-case letters.
- * When lc is at least 3, the literal coding can take advantage of
- * this property in the uncompressed data.
- *
- * There is a limit that applies to literal context bits and literal
- * position bits together: lc + lp <= 4. Without this limit the
- * decoding could become very slow, which could have security related
- * results in some cases like email servers doing virus scanning.
- * This limit also simplifies the internal implementation in liblzma.
- *
- * There may be LZMA1 streams that have lc + lp > 4 (maximum possible
- * lc would be 8). It is not possible to decode such streams with
- * liblzma.
- */
- uint32_t lc;
-# define LZMA_LCLP_MIN 0
-# define LZMA_LCLP_MAX 4
-# define LZMA_LC_DEFAULT 3
-
- /**
- * \brief Number of literal position bits
- *
- * lp affects what kind of alignment in the uncompressed data is
- * assumed when encoding literals. A literal is a single 8-bit byte.
- * See pb below for more information about alignment.
- */
- uint32_t lp;
-# define LZMA_LP_DEFAULT 0
-
- /**
- * \brief Number of position bits
- *
- * pb affects what kind of alignment in the uncompressed data is
- * assumed in general. The default means four-byte alignment
- * (2^ pb =2^2=4), which is often a good choice when there's
- * no better guess.
- *
- * When the aligment is known, setting pb accordingly may reduce
- * the file size a little. E.g. with text files having one-byte
- * alignment (US-ASCII, ISO-8859-*, UTF-8), setting pb=0 can
- * improve compression slightly. For UTF-16 text, pb=1 is a good
- * choice. If the alignment is an odd number like 3 bytes, pb=0
- * might be the best choice.
- *
- * Even though the assumed alignment can be adjusted with pb and
- * lp, LZMA1 and LZMA2 still slightly favor 16-byte alignment.
- * It might be worth taking into account when designing file formats
- * that are likely to be often compressed with LZMA1 or LZMA2.
- */
- uint32_t pb;
-# define LZMA_PB_MIN 0
-# define LZMA_PB_MAX 4
-# define LZMA_PB_DEFAULT 2
-
- /** Compression mode */
- lzma_mode mode;
-
- /**
- * \brief Nice length of a match
- *
- * This determines how many bytes the encoder compares from the match
- * candidates when looking for the best match. Once a match of at
- * least nice_len bytes long is found, the encoder stops looking for
- * better candidates and encodes the match. (Naturally, if the found
- * match is actually longer than nice_len, the actual length is
- * encoded; it's not truncated to nice_len.)
- *
- * Bigger values usually increase the compression ratio and
- * compression time. For most files, 32 to 128 is a good value,
- * which gives very good compression ratio at good speed.
- *
- * The exact minimum value depends on the match finder. The maximum
- * is 273, which is the maximum length of a match that LZMA1 and
- * LZMA2 can encode.
- */
- uint32_t nice_len;
-
- /** Match finder ID */
- lzma_match_finder mf;
-
- /**
- * \brief Maximum search depth in the match finder
- *
- * For every input byte, match finder searches through the hash chain
- * or binary tree in a loop, each iteration going one step deeper in
- * the chain or tree. The searching stops if
- * - a match of at least nice_len bytes long is found;
- * - all match candidates from the hash chain or binary tree have
- * been checked; or
- * - maximum search depth is reached.
- *
- * Maximum search depth is needed to prevent the match finder from
- * wasting too much time in case there are lots of short match
- * candidates. On the other hand, stopping the search before all
- * candidates have been checked can reduce compression ratio.
- *
- * Setting depth to zero tells liblzma to use an automatic default
- * value, that depends on the selected match finder and nice_len.
- * The default is in the range [4, 200] or so (it may vary between
- * liblzma versions).
- *
- * Using a bigger depth value than the default can increase
- * compression ratio in some cases. There is no strict maximum value,
- * but high values (thousands or millions) should be used with care:
- * the encoder could remain fast enough with typical input, but
- * malicious input could cause the match finder to slow down
- * dramatically, possibly creating a denial of service attack.
- */
- uint32_t depth;
-
- /*
- * Reserved space to allow possible future extensions without
- * breaking the ABI. You should not touch these, because the names
- * of these variables may change. These are and will never be used
- * with the currently supported options, so it is safe to leave these
- * uninitialized.
- */
- uint32_t reserved_int1;
- uint32_t reserved_int2;
- uint32_t reserved_int3;
- uint32_t reserved_int4;
- uint32_t reserved_int5;
- uint32_t reserved_int6;
- uint32_t reserved_int7;
- uint32_t reserved_int8;
- lzma_reserved_enum reserved_enum1;
- lzma_reserved_enum reserved_enum2;
- lzma_reserved_enum reserved_enum3;
- lzma_reserved_enum reserved_enum4;
- void *reserved_ptr1;
- void *reserved_ptr2;
-
-} lzma_options_lzma;
-
-
-/**
- * \brief Set a compression preset to lzma_options_lzma structure
- *
- * 0 is the fastest and 9 is the slowest. These match the switches -0 .. -9
- * of the xz command line tool. In addition, it is possible to bitwise-or
- * flags to the preset. Currently only LZMA_PRESET_EXTREME is supported.
- * The flags are defined in container.h, because the flags are used also
- * with lzma_easy_encoder().
- *
- * The preset values are subject to changes between liblzma versions.
- *
- * This function is available only if LZMA1 or LZMA2 encoder has been enabled
- * when building liblzma.
- *
- * \return On success, false is returned. If the preset is not
- * supported, true is returned.
- */
-extern LZMA_API(lzma_bool) lzma_lzma_preset(
- lzma_options_lzma *options, uint32_t preset) lzma_nothrow;