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annotate CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/include/lzma/lzma12.h @ 69:33d812a61356

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planemo upload commit 2e9511a184a1ca667c7be0c6321a36dc4e3d116d
author jpayne
date Tue, 18 Mar 2025 17:55:14 -0400
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jpayne@69 1 /* SPDX-License-Identifier: 0BSD */
jpayne@69 2
jpayne@69 3 /**
jpayne@69 4 * \file lzma/lzma12.h
jpayne@69 5 * \brief LZMA1 and LZMA2 filters
jpayne@69 6 * \note Never include this file directly. Use <lzma.h> instead.
jpayne@69 7 */
jpayne@69 8
jpayne@69 9 /*
jpayne@69 10 * Author: Lasse Collin
jpayne@69 11 */
jpayne@69 12
jpayne@69 13 #ifndef LZMA_H_INTERNAL
jpayne@69 14 # error Never include this file directly. Use <lzma.h> instead.
jpayne@69 15 #endif
jpayne@69 16
jpayne@69 17
jpayne@69 18 /**
jpayne@69 19 * \brief LZMA1 Filter ID (for raw encoder/decoder only, not in .xz)
jpayne@69 20 *
jpayne@69 21 * LZMA1 is the very same thing as what was called just LZMA in LZMA Utils,
jpayne@69 22 * 7-Zip, and LZMA SDK. It's called LZMA1 here to prevent developers from
jpayne@69 23 * accidentally using LZMA when they actually want LZMA2.
jpayne@69 24 */
jpayne@69 25 #define LZMA_FILTER_LZMA1 LZMA_VLI_C(0x4000000000000001)
jpayne@69 26
jpayne@69 27 /**
jpayne@69 28 * \brief LZMA1 Filter ID with extended options (for raw encoder/decoder)
jpayne@69 29 *
jpayne@69 30 * This is like LZMA_FILTER_LZMA1 but with this ID a few extra options
jpayne@69 31 * are supported in the lzma_options_lzma structure:
jpayne@69 32 *
jpayne@69 33 * - A flag to tell the encoder if the end of payload marker (EOPM) alias
jpayne@69 34 * end of stream (EOS) marker must be written at the end of the stream.
jpayne@69 35 * In contrast, LZMA_FILTER_LZMA1 always writes the end marker.
jpayne@69 36 *
jpayne@69 37 * - Decoder needs to be told the uncompressed size of the stream
jpayne@69 38 * or that it is unknown (using the special value UINT64_MAX).
jpayne@69 39 * If the size is known, a flag can be set to allow the presence of
jpayne@69 40 * the end marker anyway. In contrast, LZMA_FILTER_LZMA1 always
jpayne@69 41 * behaves as if the uncompressed size was unknown.
jpayne@69 42 *
jpayne@69 43 * This allows handling file formats where LZMA1 streams are used but where
jpayne@69 44 * the end marker isn't allowed or where it might not (always) be present.
jpayne@69 45 * This extended LZMA1 functionality is provided as a Filter ID for raw
jpayne@69 46 * encoder and decoder instead of adding new encoder and decoder initialization
jpayne@69 47 * functions because this way it is possible to also use extra filters,
jpayne@69 48 * for example, LZMA_FILTER_X86 in a filter chain with LZMA_FILTER_LZMA1EXT,
jpayne@69 49 * which might be needed to handle some file formats.
jpayne@69 50 */
jpayne@69 51 #define LZMA_FILTER_LZMA1EXT LZMA_VLI_C(0x4000000000000002)
jpayne@69 52
jpayne@69 53 /**
jpayne@69 54 * \brief LZMA2 Filter ID
jpayne@69 55 *
jpayne@69 56 * Usually you want this instead of LZMA1. Compared to LZMA1, LZMA2 adds
jpayne@69 57 * support for LZMA_SYNC_FLUSH, uncompressed chunks (smaller expansion
jpayne@69 58 * when trying to compress incompressible data), possibility to change
jpayne@69 59 * lc/lp/pb in the middle of encoding, and some other internal improvements.
jpayne@69 60 */
jpayne@69 61 #define LZMA_FILTER_LZMA2 LZMA_VLI_C(0x21)
jpayne@69 62
jpayne@69 63
jpayne@69 64 /**
jpayne@69 65 * \brief Match finders
jpayne@69 66 *
jpayne@69 67 * Match finder has major effect on both speed and compression ratio.
jpayne@69 68 * Usually hash chains are faster than binary trees.
jpayne@69 69 *
jpayne@69 70 * If you will use LZMA_SYNC_FLUSH often, the hash chains may be a better
jpayne@69 71 * choice, because binary trees get much higher compression ratio penalty
jpayne@69 72 * with LZMA_SYNC_FLUSH.
jpayne@69 73 *
jpayne@69 74 * The memory usage formulas are only rough estimates, which are closest to
jpayne@69 75 * reality when dict_size is a power of two. The formulas are more complex
jpayne@69 76 * in reality, and can also change a little between liblzma versions. Use
jpayne@69 77 * lzma_raw_encoder_memusage() to get more accurate estimate of memory usage.
jpayne@69 78 */
jpayne@69 79 typedef enum {
jpayne@69 80 LZMA_MF_HC3 = 0x03,
jpayne@69 81 /**<
jpayne@69 82 * \brief Hash Chain with 2- and 3-byte hashing
jpayne@69 83 *
jpayne@69 84 * Minimum nice_len: 3
jpayne@69 85 *
jpayne@69 86 * Memory usage:
jpayne@69 87 * - dict_size <= 16 MiB: dict_size * 7.5
jpayne@69 88 * - dict_size > 16 MiB: dict_size * 5.5 + 64 MiB
jpayne@69 89 */
jpayne@69 90
jpayne@69 91 LZMA_MF_HC4 = 0x04,
jpayne@69 92 /**<
jpayne@69 93 * \brief Hash Chain with 2-, 3-, and 4-byte hashing
jpayne@69 94 *
jpayne@69 95 * Minimum nice_len: 4
jpayne@69 96 *
jpayne@69 97 * Memory usage:
jpayne@69 98 * - dict_size <= 32 MiB: dict_size * 7.5
jpayne@69 99 * - dict_size > 32 MiB: dict_size * 6.5
jpayne@69 100 */
jpayne@69 101
jpayne@69 102 LZMA_MF_BT2 = 0x12,
jpayne@69 103 /**<
jpayne@69 104 * \brief Binary Tree with 2-byte hashing
jpayne@69 105 *
jpayne@69 106 * Minimum nice_len: 2
jpayne@69 107 *
jpayne@69 108 * Memory usage: dict_size * 9.5
jpayne@69 109 */
jpayne@69 110
jpayne@69 111 LZMA_MF_BT3 = 0x13,
jpayne@69 112 /**<
jpayne@69 113 * \brief Binary Tree with 2- and 3-byte hashing
jpayne@69 114 *
jpayne@69 115 * Minimum nice_len: 3
jpayne@69 116 *
jpayne@69 117 * Memory usage:
jpayne@69 118 * - dict_size <= 16 MiB: dict_size * 11.5
jpayne@69 119 * - dict_size > 16 MiB: dict_size * 9.5 + 64 MiB
jpayne@69 120 */
jpayne@69 121
jpayne@69 122 LZMA_MF_BT4 = 0x14
jpayne@69 123 /**<
jpayne@69 124 * \brief Binary Tree with 2-, 3-, and 4-byte hashing
jpayne@69 125 *
jpayne@69 126 * Minimum nice_len: 4
jpayne@69 127 *
jpayne@69 128 * Memory usage:
jpayne@69 129 * - dict_size <= 32 MiB: dict_size * 11.5
jpayne@69 130 * - dict_size > 32 MiB: dict_size * 10.5
jpayne@69 131 */
jpayne@69 132 } lzma_match_finder;
jpayne@69 133
jpayne@69 134
jpayne@69 135 /**
jpayne@69 136 * \brief Test if given match finder is supported
jpayne@69 137 *
jpayne@69 138 * It is safe to call this with a value that isn't listed in
jpayne@69 139 * lzma_match_finder enumeration; the return value will be false.
jpayne@69 140 *
jpayne@69 141 * There is no way to list which match finders are available in this
jpayne@69 142 * particular liblzma version and build. It would be useless, because
jpayne@69 143 * a new match finder, which the application developer wasn't aware,
jpayne@69 144 * could require giving additional options to the encoder that the older
jpayne@69 145 * match finders don't need.
jpayne@69 146 *
jpayne@69 147 * \param match_finder Match finder ID
jpayne@69 148 *
jpayne@69 149 * \return lzma_bool:
jpayne@69 150 * - true if the match finder is supported by this liblzma build.
jpayne@69 151 * - false otherwise.
jpayne@69 152 */
jpayne@69 153 extern LZMA_API(lzma_bool) lzma_mf_is_supported(lzma_match_finder match_finder)
jpayne@69 154 lzma_nothrow lzma_attr_const;
jpayne@69 155
jpayne@69 156
jpayne@69 157 /**
jpayne@69 158 * \brief Compression modes
jpayne@69 159 *
jpayne@69 160 * This selects the function used to analyze the data produced by the match
jpayne@69 161 * finder.
jpayne@69 162 */
jpayne@69 163 typedef enum {
jpayne@69 164 LZMA_MODE_FAST = 1,
jpayne@69 165 /**<
jpayne@69 166 * \brief Fast compression
jpayne@69 167 *
jpayne@69 168 * Fast mode is usually at its best when combined with
jpayne@69 169 * a hash chain match finder.
jpayne@69 170 */
jpayne@69 171
jpayne@69 172 LZMA_MODE_NORMAL = 2
jpayne@69 173 /**<
jpayne@69 174 * \brief Normal compression
jpayne@69 175 *
jpayne@69 176 * This is usually notably slower than fast mode. Use this
jpayne@69 177 * together with binary tree match finders to expose the
jpayne@69 178 * full potential of the LZMA1 or LZMA2 encoder.
jpayne@69 179 */
jpayne@69 180 } lzma_mode;
jpayne@69 181
jpayne@69 182
jpayne@69 183 /**
jpayne@69 184 * \brief Test if given compression mode is supported
jpayne@69 185 *
jpayne@69 186 * It is safe to call this with a value that isn't listed in lzma_mode
jpayne@69 187 * enumeration; the return value will be false.
jpayne@69 188 *
jpayne@69 189 * There is no way to list which modes are available in this particular
jpayne@69 190 * liblzma version and build. It would be useless, because a new compression
jpayne@69 191 * mode, which the application developer wasn't aware, could require giving
jpayne@69 192 * additional options to the encoder that the older modes don't need.
jpayne@69 193 *
jpayne@69 194 * \param mode Mode ID.
jpayne@69 195 *
jpayne@69 196 * \return lzma_bool:
jpayne@69 197 * - true if the compression mode is supported by this liblzma
jpayne@69 198 * build.
jpayne@69 199 * - false otherwise.
jpayne@69 200 */
jpayne@69 201 extern LZMA_API(lzma_bool) lzma_mode_is_supported(lzma_mode mode)
jpayne@69 202 lzma_nothrow lzma_attr_const;
jpayne@69 203
jpayne@69 204
jpayne@69 205 /**
jpayne@69 206 * \brief Options specific to the LZMA1 and LZMA2 filters
jpayne@69 207 *
jpayne@69 208 * Since LZMA1 and LZMA2 share most of the code, it's simplest to share
jpayne@69 209 * the options structure too. For encoding, all but the reserved variables
jpayne@69 210 * need to be initialized unless specifically mentioned otherwise.
jpayne@69 211 * lzma_lzma_preset() can be used to get a good starting point.
jpayne@69 212 *
jpayne@69 213 * For raw decoding, both LZMA1 and LZMA2 need dict_size, preset_dict, and
jpayne@69 214 * preset_dict_size (if preset_dict != NULL). LZMA1 needs also lc, lp, and pb.
jpayne@69 215 */
jpayne@69 216 typedef struct {
jpayne@69 217 /**
jpayne@69 218 * \brief Dictionary size in bytes
jpayne@69 219 *
jpayne@69 220 * Dictionary size indicates how many bytes of the recently processed
jpayne@69 221 * uncompressed data is kept in memory. One method to reduce size of
jpayne@69 222 * the uncompressed data is to store distance-length pairs, which
jpayne@69 223 * indicate what data to repeat from the dictionary buffer. Thus,
jpayne@69 224 * the bigger the dictionary, the better the compression ratio
jpayne@69 225 * usually is.
jpayne@69 226 *
jpayne@69 227 * Maximum size of the dictionary depends on multiple things:
jpayne@69 228 * - Memory usage limit
jpayne@69 229 * - Available address space (not a problem on 64-bit systems)
jpayne@69 230 * - Selected match finder (encoder only)
jpayne@69 231 *
jpayne@69 232 * Currently the maximum dictionary size for encoding is 1.5 GiB
jpayne@69 233 * (i.e. (UINT32_C(1) << 30) + (UINT32_C(1) << 29)) even on 64-bit
jpayne@69 234 * systems for certain match finder implementation reasons. In the
jpayne@69 235 * future, there may be match finders that support bigger
jpayne@69 236 * dictionaries.
jpayne@69 237 *
jpayne@69 238 * Decoder already supports dictionaries up to 4 GiB - 1 B (i.e.
jpayne@69 239 * UINT32_MAX), so increasing the maximum dictionary size of the
jpayne@69 240 * encoder won't cause problems for old decoders.
jpayne@69 241 *
jpayne@69 242 * Because extremely small dictionaries sizes would have unneeded
jpayne@69 243 * overhead in the decoder, the minimum dictionary size is 4096 bytes.
jpayne@69 244 *
jpayne@69 245 * \note When decoding, too big dictionary does no other harm
jpayne@69 246 * than wasting memory.
jpayne@69 247 */
jpayne@69 248 uint32_t dict_size;
jpayne@69 249 # define LZMA_DICT_SIZE_MIN UINT32_C(4096)
jpayne@69 250 # define LZMA_DICT_SIZE_DEFAULT (UINT32_C(1) << 23)
jpayne@69 251
jpayne@69 252 /**
jpayne@69 253 * \brief Pointer to an initial dictionary
jpayne@69 254 *
jpayne@69 255 * It is possible to initialize the LZ77 history window using
jpayne@69 256 * a preset dictionary. It is useful when compressing many
jpayne@69 257 * similar, relatively small chunks of data independently from
jpayne@69 258 * each other. The preset dictionary should contain typical
jpayne@69 259 * strings that occur in the files being compressed. The most
jpayne@69 260 * probable strings should be near the end of the preset dictionary.
jpayne@69 261 *
jpayne@69 262 * This feature should be used only in special situations. For
jpayne@69 263 * now, it works correctly only with raw encoding and decoding.
jpayne@69 264 * Currently none of the container formats supported by
jpayne@69 265 * liblzma allow preset dictionary when decoding, thus if
jpayne@69 266 * you create a .xz or .lzma file with preset dictionary, it
jpayne@69 267 * cannot be decoded with the regular decoder functions. In the
jpayne@69 268 * future, the .xz format will likely get support for preset
jpayne@69 269 * dictionary though.
jpayne@69 270 */
jpayne@69 271 const uint8_t *preset_dict;
jpayne@69 272
jpayne@69 273 /**
jpayne@69 274 * \brief Size of the preset dictionary
jpayne@69 275 *
jpayne@69 276 * Specifies the size of the preset dictionary. If the size is
jpayne@69 277 * bigger than dict_size, only the last dict_size bytes are
jpayne@69 278 * processed.
jpayne@69 279 *
jpayne@69 280 * This variable is read only when preset_dict is not NULL.
jpayne@69 281 * If preset_dict is not NULL but preset_dict_size is zero,
jpayne@69 282 * no preset dictionary is used (identical to only setting
jpayne@69 283 * preset_dict to NULL).
jpayne@69 284 */
jpayne@69 285 uint32_t preset_dict_size;
jpayne@69 286
jpayne@69 287 /**
jpayne@69 288 * \brief Number of literal context bits
jpayne@69 289 *
jpayne@69 290 * How many of the highest bits of the previous uncompressed
jpayne@69 291 * eight-bit byte (also known as 'literal') are taken into
jpayne@69 292 * account when predicting the bits of the next literal.
jpayne@69 293 *
jpayne@69 294 * E.g. in typical English text, an upper-case letter is
jpayne@69 295 * often followed by a lower-case letter, and a lower-case
jpayne@69 296 * letter is usually followed by another lower-case letter.
jpayne@69 297 * In the US-ASCII character set, the highest three bits are 010
jpayne@69 298 * for upper-case letters and 011 for lower-case letters.
jpayne@69 299 * When lc is at least 3, the literal coding can take advantage of
jpayne@69 300 * this property in the uncompressed data.
jpayne@69 301 *
jpayne@69 302 * There is a limit that applies to literal context bits and literal
jpayne@69 303 * position bits together: lc + lp <= 4. Without this limit the
jpayne@69 304 * decoding could become very slow, which could have security related
jpayne@69 305 * results in some cases like email servers doing virus scanning.
jpayne@69 306 * This limit also simplifies the internal implementation in liblzma.
jpayne@69 307 *
jpayne@69 308 * There may be LZMA1 streams that have lc + lp > 4 (maximum possible
jpayne@69 309 * lc would be 8). It is not possible to decode such streams with
jpayne@69 310 * liblzma.
jpayne@69 311 */
jpayne@69 312 uint32_t lc;
jpayne@69 313 # define LZMA_LCLP_MIN 0
jpayne@69 314 # define LZMA_LCLP_MAX 4
jpayne@69 315 # define LZMA_LC_DEFAULT 3
jpayne@69 316
jpayne@69 317 /**
jpayne@69 318 * \brief Number of literal position bits
jpayne@69 319 *
jpayne@69 320 * lp affects what kind of alignment in the uncompressed data is
jpayne@69 321 * assumed when encoding literals. A literal is a single 8-bit byte.
jpayne@69 322 * See pb below for more information about alignment.
jpayne@69 323 */
jpayne@69 324 uint32_t lp;
jpayne@69 325 # define LZMA_LP_DEFAULT 0
jpayne@69 326
jpayne@69 327 /**
jpayne@69 328 * \brief Number of position bits
jpayne@69 329 *
jpayne@69 330 * pb affects what kind of alignment in the uncompressed data is
jpayne@69 331 * assumed in general. The default means four-byte alignment
jpayne@69 332 * (2^ pb =2^2=4), which is often a good choice when there's
jpayne@69 333 * no better guess.
jpayne@69 334 *
jpayne@69 335 * When the alignment is known, setting pb accordingly may reduce
jpayne@69 336 * the file size a little. E.g. with text files having one-byte
jpayne@69 337 * alignment (US-ASCII, ISO-8859-*, UTF-8), setting pb=0 can
jpayne@69 338 * improve compression slightly. For UTF-16 text, pb=1 is a good
jpayne@69 339 * choice. If the alignment is an odd number like 3 bytes, pb=0
jpayne@69 340 * might be the best choice.
jpayne@69 341 *
jpayne@69 342 * Even though the assumed alignment can be adjusted with pb and
jpayne@69 343 * lp, LZMA1 and LZMA2 still slightly favor 16-byte alignment.
jpayne@69 344 * It might be worth taking into account when designing file formats
jpayne@69 345 * that are likely to be often compressed with LZMA1 or LZMA2.
jpayne@69 346 */
jpayne@69 347 uint32_t pb;
jpayne@69 348 # define LZMA_PB_MIN 0
jpayne@69 349 # define LZMA_PB_MAX 4
jpayne@69 350 # define LZMA_PB_DEFAULT 2
jpayne@69 351
jpayne@69 352 /** Compression mode */
jpayne@69 353 lzma_mode mode;
jpayne@69 354
jpayne@69 355 /**
jpayne@69 356 * \brief Nice length of a match
jpayne@69 357 *
jpayne@69 358 * This determines how many bytes the encoder compares from the match
jpayne@69 359 * candidates when looking for the best match. Once a match of at
jpayne@69 360 * least nice_len bytes long is found, the encoder stops looking for
jpayne@69 361 * better candidates and encodes the match. (Naturally, if the found
jpayne@69 362 * match is actually longer than nice_len, the actual length is
jpayne@69 363 * encoded; it's not truncated to nice_len.)
jpayne@69 364 *
jpayne@69 365 * Bigger values usually increase the compression ratio and
jpayne@69 366 * compression time. For most files, 32 to 128 is a good value,
jpayne@69 367 * which gives very good compression ratio at good speed.
jpayne@69 368 *
jpayne@69 369 * The exact minimum value depends on the match finder. The maximum
jpayne@69 370 * is 273, which is the maximum length of a match that LZMA1 and
jpayne@69 371 * LZMA2 can encode.
jpayne@69 372 */
jpayne@69 373 uint32_t nice_len;
jpayne@69 374
jpayne@69 375 /** Match finder ID */
jpayne@69 376 lzma_match_finder mf;
jpayne@69 377
jpayne@69 378 /**
jpayne@69 379 * \brief Maximum search depth in the match finder
jpayne@69 380 *
jpayne@69 381 * For every input byte, match finder searches through the hash chain
jpayne@69 382 * or binary tree in a loop, each iteration going one step deeper in
jpayne@69 383 * the chain or tree. The searching stops if
jpayne@69 384 * - a match of at least nice_len bytes long is found;
jpayne@69 385 * - all match candidates from the hash chain or binary tree have
jpayne@69 386 * been checked; or
jpayne@69 387 * - maximum search depth is reached.
jpayne@69 388 *
jpayne@69 389 * Maximum search depth is needed to prevent the match finder from
jpayne@69 390 * wasting too much time in case there are lots of short match
jpayne@69 391 * candidates. On the other hand, stopping the search before all
jpayne@69 392 * candidates have been checked can reduce compression ratio.
jpayne@69 393 *
jpayne@69 394 * Setting depth to zero tells liblzma to use an automatic default
jpayne@69 395 * value, that depends on the selected match finder and nice_len.
jpayne@69 396 * The default is in the range [4, 200] or so (it may vary between
jpayne@69 397 * liblzma versions).
jpayne@69 398 *
jpayne@69 399 * Using a bigger depth value than the default can increase
jpayne@69 400 * compression ratio in some cases. There is no strict maximum value,
jpayne@69 401 * but high values (thousands or millions) should be used with care:
jpayne@69 402 * the encoder could remain fast enough with typical input, but
jpayne@69 403 * malicious input could cause the match finder to slow down
jpayne@69 404 * dramatically, possibly creating a denial of service attack.
jpayne@69 405 */
jpayne@69 406 uint32_t depth;
jpayne@69 407
jpayne@69 408 /**
jpayne@69 409 * \brief For LZMA_FILTER_LZMA1EXT: Extended flags
jpayne@69 410 *
jpayne@69 411 * This is used only with LZMA_FILTER_LZMA1EXT.
jpayne@69 412 *
jpayne@69 413 * Currently only one flag is supported, LZMA_LZMA1EXT_ALLOW_EOPM:
jpayne@69 414 *
jpayne@69 415 * - Encoder: If the flag is set, then end marker is written just
jpayne@69 416 * like it is with LZMA_FILTER_LZMA1. Without this flag the
jpayne@69 417 * end marker isn't written and the application has to store
jpayne@69 418 * the uncompressed size somewhere outside the compressed stream.
jpayne@69 419 * To decompress streams without the end marker, the application
jpayne@69 420 * has to set the correct uncompressed size in ext_size_low and
jpayne@69 421 * ext_size_high.
jpayne@69 422 *
jpayne@69 423 * - Decoder: If the uncompressed size in ext_size_low and
jpayne@69 424 * ext_size_high is set to the special value UINT64_MAX
jpayne@69 425 * (indicating unknown uncompressed size) then this flag is
jpayne@69 426 * ignored and the end marker must always be present, that is,
jpayne@69 427 * the behavior is identical to LZMA_FILTER_LZMA1.
jpayne@69 428 *
jpayne@69 429 * Otherwise, if this flag isn't set, then the input stream
jpayne@69 430 * must not have the end marker; if the end marker is detected
jpayne@69 431 * then it will result in LZMA_DATA_ERROR. This is useful when
jpayne@69 432 * it is known that the stream must not have the end marker and
jpayne@69 433 * strict validation is wanted.
jpayne@69 434 *
jpayne@69 435 * If this flag is set, then it is autodetected if the end marker
jpayne@69 436 * is present after the specified number of uncompressed bytes
jpayne@69 437 * has been decompressed (ext_size_low and ext_size_high). The
jpayne@69 438 * end marker isn't allowed in any other position. This behavior
jpayne@69 439 * is useful when uncompressed size is known but the end marker
jpayne@69 440 * may or may not be present. This is the case, for example,
jpayne@69 441 * in .7z files (valid .7z files that have the end marker in
jpayne@69 442 * LZMA1 streams are rare but they do exist).
jpayne@69 443 */
jpayne@69 444 uint32_t ext_flags;
jpayne@69 445 # define LZMA_LZMA1EXT_ALLOW_EOPM UINT32_C(0x01)
jpayne@69 446
jpayne@69 447 /**
jpayne@69 448 * \brief For LZMA_FILTER_LZMA1EXT: Uncompressed size (low bits)
jpayne@69 449 *
jpayne@69 450 * The 64-bit uncompressed size is needed for decompression with
jpayne@69 451 * LZMA_FILTER_LZMA1EXT. The size is ignored by the encoder.
jpayne@69 452 *
jpayne@69 453 * The special value UINT64_MAX indicates that the uncompressed size
jpayne@69 454 * is unknown and that the end of payload marker (also known as
jpayne@69 455 * end of stream marker) must be present to indicate the end of
jpayne@69 456 * the LZMA1 stream. Any other value indicates the expected
jpayne@69 457 * uncompressed size of the LZMA1 stream. (If LZMA1 was used together
jpayne@69 458 * with filters that change the size of the data then the uncompressed
jpayne@69 459 * size of the LZMA1 stream could be different than the final
jpayne@69 460 * uncompressed size of the filtered stream.)
jpayne@69 461 *
jpayne@69 462 * ext_size_low holds the least significant 32 bits of the
jpayne@69 463 * uncompressed size. The most significant 32 bits must be set
jpayne@69 464 * in ext_size_high. The macro lzma_set_ext_size(opt_lzma, u64size)
jpayne@69 465 * can be used to set these members.
jpayne@69 466 *
jpayne@69 467 * The 64-bit uncompressed size is split into two uint32_t variables
jpayne@69 468 * because there were no reserved uint64_t members and using the
jpayne@69 469 * same options structure for LZMA_FILTER_LZMA1, LZMA_FILTER_LZMA1EXT,
jpayne@69 470 * and LZMA_FILTER_LZMA2 was otherwise more convenient than having
jpayne@69 471 * a new options structure for LZMA_FILTER_LZMA1EXT. (Replacing two
jpayne@69 472 * uint32_t members with one uint64_t changes the ABI on some systems
jpayne@69 473 * as the alignment of this struct can increase from 4 bytes to 8.)
jpayne@69 474 */
jpayne@69 475 uint32_t ext_size_low;
jpayne@69 476
jpayne@69 477 /**
jpayne@69 478 * \brief For LZMA_FILTER_LZMA1EXT: Uncompressed size (high bits)
jpayne@69 479 *
jpayne@69 480 * This holds the most significant 32 bits of the uncompressed size.
jpayne@69 481 */
jpayne@69 482 uint32_t ext_size_high;
jpayne@69 483
jpayne@69 484 /*
jpayne@69 485 * Reserved space to allow possible future extensions without
jpayne@69 486 * breaking the ABI. You should not touch these, because the names
jpayne@69 487 * of these variables may change. These are and will never be used
jpayne@69 488 * with the currently supported options, so it is safe to leave these
jpayne@69 489 * uninitialized.
jpayne@69 490 */
jpayne@69 491
jpayne@69 492 /** \private Reserved member. */
jpayne@69 493 uint32_t reserved_int4;
jpayne@69 494
jpayne@69 495 /** \private Reserved member. */
jpayne@69 496 uint32_t reserved_int5;
jpayne@69 497
jpayne@69 498 /** \private Reserved member. */
jpayne@69 499 uint32_t reserved_int6;
jpayne@69 500
jpayne@69 501 /** \private Reserved member. */
jpayne@69 502 uint32_t reserved_int7;
jpayne@69 503
jpayne@69 504 /** \private Reserved member. */
jpayne@69 505 uint32_t reserved_int8;
jpayne@69 506
jpayne@69 507 /** \private Reserved member. */
jpayne@69 508 lzma_reserved_enum reserved_enum1;
jpayne@69 509
jpayne@69 510 /** \private Reserved member. */
jpayne@69 511 lzma_reserved_enum reserved_enum2;
jpayne@69 512
jpayne@69 513 /** \private Reserved member. */
jpayne@69 514 lzma_reserved_enum reserved_enum3;
jpayne@69 515
jpayne@69 516 /** \private Reserved member. */
jpayne@69 517 lzma_reserved_enum reserved_enum4;
jpayne@69 518
jpayne@69 519 /** \private Reserved member. */
jpayne@69 520 void *reserved_ptr1;
jpayne@69 521
jpayne@69 522 /** \private Reserved member. */
jpayne@69 523 void *reserved_ptr2;
jpayne@69 524
jpayne@69 525 } lzma_options_lzma;
jpayne@69 526
jpayne@69 527
jpayne@69 528 /**
jpayne@69 529 * \brief Macro to set the 64-bit uncompressed size in ext_size_*
jpayne@69 530 *
jpayne@69 531 * This might be convenient when decoding using LZMA_FILTER_LZMA1EXT.
jpayne@69 532 * This isn't used with LZMA_FILTER_LZMA1 or LZMA_FILTER_LZMA2.
jpayne@69 533 */
jpayne@69 534 #define lzma_set_ext_size(opt_lzma2, u64size) \
jpayne@69 535 do { \
jpayne@69 536 (opt_lzma2).ext_size_low = (uint32_t)(u64size); \
jpayne@69 537 (opt_lzma2).ext_size_high = (uint32_t)((uint64_t)(u64size) >> 32); \
jpayne@69 538 } while (0)
jpayne@69 539
jpayne@69 540
jpayne@69 541 /**
jpayne@69 542 * \brief Set a compression preset to lzma_options_lzma structure
jpayne@69 543 *
jpayne@69 544 * 0 is the fastest and 9 is the slowest. These match the switches -0 .. -9
jpayne@69 545 * of the xz command line tool. In addition, it is possible to bitwise-or
jpayne@69 546 * flags to the preset. Currently only LZMA_PRESET_EXTREME is supported.
jpayne@69 547 * The flags are defined in container.h, because the flags are used also
jpayne@69 548 * with lzma_easy_encoder().
jpayne@69 549 *
jpayne@69 550 * The preset levels are subject to changes between liblzma versions.
jpayne@69 551 *
jpayne@69 552 * This function is available only if LZMA1 or LZMA2 encoder has been enabled
jpayne@69 553 * when building liblzma.
jpayne@69 554 *
jpayne@69 555 * If features (like certain match finders) have been disabled at build time,
jpayne@69 556 * then the function may return success (false) even though the resulting
jpayne@69 557 * LZMA1/LZMA2 options may not be usable for encoder initialization
jpayne@69 558 * (LZMA_OPTIONS_ERROR).
jpayne@69 559 *
jpayne@69 560 * \param[out] options Pointer to LZMA1 or LZMA2 options to be filled
jpayne@69 561 * \param preset Preset level bitwse-ORed with preset flags
jpayne@69 562 *
jpayne@69 563 * \return lzma_bool:
jpayne@69 564 * - true if the preset is not supported (failure).
jpayne@69 565 * - false otherwise (success).
jpayne@69 566 */
jpayne@69 567 extern LZMA_API(lzma_bool) lzma_lzma_preset(
jpayne@69 568 lzma_options_lzma *options, uint32_t preset) lzma_nothrow;