1 /** 2 * \file lzma/container.h 3 * \brief File formats 4 * \note Never include this file directly. Use <lzma.h> instead. 5 */ 6 7 /* 8 * Author: Lasse Collin 9 * 10 * This file has been put into the public domain. 11 * You can do whatever you want with this file. 12 */ 13 14 #ifndef LZMA_H_INTERNAL 15 # error Never include this file directly. Use <lzma.h> instead. 16 #endif 17 18 19 /************ 20 * Encoding * 21 ************/ 22 23 /** 24 * \brief Default compression preset 25 * 26 * It's not straightforward to recommend a default preset, because in some 27 * cases keeping the resource usage relatively low is more important that 28 * getting the maximum compression ratio. 29 */ 30 #define LZMA_PRESET_DEFAULT UINT32_C(6) 31 32 33 /** 34 * \brief Mask for preset level 35 * 36 * This is useful only if you need to extract the level from the preset 37 * variable. That should be rare. 38 */ 39 #define LZMA_PRESET_LEVEL_MASK UINT32_C(0x1F) 40 41 42 /* 43 * Preset flags 44 * 45 * Currently only one flag is defined. 46 */ 47 48 /** 49 * \brief Extreme compression preset 50 * 51 * This flag modifies the preset to make the encoding significantly slower 52 * while improving the compression ratio only marginally. This is useful 53 * when you don't mind spending time to get as small result as possible. 54 * 55 * This flag doesn't affect the memory usage requirements of the decoder (at 56 * least not significantly). The memory usage of the encoder may be increased 57 * a little but only at the lowest preset levels (0-3). 58 */ 59 #define LZMA_PRESET_EXTREME (UINT32_C(1) << 31) 60 61 62 /** 63 * \brief Multithreading options 64 */ 65 typedef struct { 66 /** 67 * \brief Flags 68 * 69 * Set this to zero if no flags are wanted. 70 * 71 * Encoder: No flags are currently supported. 72 * 73 * Decoder: Bitwise-or of zero or more of the decoder flags: 74 * - LZMA_TELL_NO_CHECK 75 * - LZMA_TELL_UNSUPPORTED_CHECK 76 * - LZMA_TELL_ANY_CHECK 77 * - LZMA_IGNORE_CHECK 78 * - LZMA_CONCATENATED 79 * - LZMA_FAIL_FAST 80 */ 81 uint32_t flags; 82 83 /** 84 * \brief Number of worker threads to use 85 */ 86 uint32_t threads; 87 88 /** 89 * \brief Encoder only: Maximum uncompressed size of a Block 90 * 91 * The encoder will start a new .xz Block every block_size bytes. 92 * Using LZMA_FULL_FLUSH or LZMA_FULL_BARRIER with lzma_code() 93 * the caller may tell liblzma to start a new Block earlier. 94 * 95 * With LZMA2, a recommended block size is 2-4 times the LZMA2 96 * dictionary size. With very small dictionaries, it is recommended 97 * to use at least 1 MiB block size for good compression ratio, even 98 * if this is more than four times the dictionary size. Note that 99 * these are only recommendations for typical use cases; feel free 100 * to use other values. Just keep in mind that using a block size 101 * less than the LZMA2 dictionary size is waste of RAM. 102 * 103 * Set this to 0 to let liblzma choose the block size depending 104 * on the compression options. For LZMA2 it will be 3*dict_size 105 * or 1 MiB, whichever is more. 106 * 107 * For each thread, about 3 * block_size bytes of memory will be 108 * allocated. This may change in later liblzma versions. If so, 109 * the memory usage will probably be reduced, not increased. 110 */ 111 uint64_t block_size; 112 113 /** 114 * \brief Timeout to allow lzma_code() to return early 115 * 116 * Multithreading can make liblzma consume input and produce 117 * output in a very bursty way: it may first read a lot of input 118 * to fill internal buffers, then no input or output occurs for 119 * a while. 120 * 121 * In single-threaded mode, lzma_code() won't return until it has 122 * either consumed all the input or filled the output buffer. If 123 * this is done in multithreaded mode, it may cause a call 124 * lzma_code() to take even tens of seconds, which isn't acceptable 125 * in all applications. 126 * 127 * To avoid very long blocking times in lzma_code(), a timeout 128 * (in milliseconds) may be set here. If lzma_code() would block 129 * longer than this number of milliseconds, it will return with 130 * LZMA_OK. Reasonable values are 100 ms or more. The xz command 131 * line tool uses 300 ms. 132 * 133 * If long blocking times are acceptable, set timeout to a special 134 * value of 0. This will disable the timeout mechanism and will make 135 * lzma_code() block until all the input is consumed or the output 136 * buffer has been filled. 137 * 138 * \note Even with a timeout, lzma_code() might sometimes take 139 * a long time to return. No timing guarantees are made. 140 */ 141 uint32_t timeout; 142 143 /** 144 * \brief Encoder only: Compression preset 145 * 146 * The preset is set just like with lzma_easy_encoder(). 147 * The preset is ignored if filters below is non-NULL. 148 */ 149 uint32_t preset; 150 151 /** 152 * \brief Encoder only: Filter chain (alternative to a preset) 153 * 154 * If this is NULL, the preset above is used. Otherwise the preset 155 * is ignored and the filter chain specified here is used. 156 */ 157 const lzma_filter *filters; 158 159 /** 160 * \brief Encoder only: Integrity check type 161 * 162 * See check.h for available checks. The xz command line tool 163 * defaults to LZMA_CHECK_CRC64, which is a good choice if you 164 * are unsure. 165 */ 166 lzma_check check; 167 168 /* 169 * Reserved space to allow possible future extensions without 170 * breaking the ABI. You should not touch these, because the names 171 * of these variables may change. These are and will never be used 172 * with the currently supported options, so it is safe to leave these 173 * uninitialized. 174 */ 175 /** \private Reserved member. */ 176 lzma_reserved_enum reserved_enum1; 177 178 /** \private Reserved member. */ 179 lzma_reserved_enum reserved_enum2; 180 181 /** \private Reserved member. */ 182 lzma_reserved_enum reserved_enum3; 183 184 /** \private Reserved member. */ 185 uint32_t reserved_int1; 186 187 /** \private Reserved member. */ 188 uint32_t reserved_int2; 189 190 /** \private Reserved member. */ 191 uint32_t reserved_int3; 192 193 /** \private Reserved member. */ 194 uint32_t reserved_int4; 195 196 /** 197 * \brief Memory usage limit to reduce the number of threads 198 * 199 * Encoder: Ignored. 200 * 201 * Decoder: 202 * 203 * If the number of threads has been set so high that more than 204 * memlimit_threading bytes of memory would be needed, the number 205 * of threads will be reduced so that the memory usage will not exceed 206 * memlimit_threading bytes. However, if memlimit_threading cannot 207 * be met even in single-threaded mode, then decoding will continue 208 * in single-threaded mode and memlimit_threading may be exceeded 209 * even by a large amount. That is, memlimit_threading will never make 210 * lzma_code() return LZMA_MEMLIMIT_ERROR. To truly cap the memory 211 * usage, see memlimit_stop below. 212 * 213 * Setting memlimit_threading to UINT64_MAX or a similar huge value 214 * means that liblzma is allowed to keep the whole compressed file 215 * and the whole uncompressed file in memory in addition to the memory 216 * needed by the decompressor data structures used by each thread! 217 * In other words, a reasonable value limit must be set here or it 218 * will cause problems sooner or later. If you have no idea what 219 * a reasonable value could be, try lzma_physmem() / 4 as a starting 220 * point. Setting this limit will never prevent decompression of 221 * a file; this will only reduce the number of threads. 222 * 223 * If memlimit_threading is greater than memlimit_stop, then the value 224 * of memlimit_stop will be used for both. 225 */ 226 uint64_t memlimit_threading; 227 228 /** 229 * \brief Memory usage limit that should never be exceeded 230 * 231 * Encoder: Ignored. 232 * 233 * Decoder: If decompressing will need more than this amount of 234 * memory even in the single-threaded mode, then lzma_code() will 235 * return LZMA_MEMLIMIT_ERROR. 236 */ 237 uint64_t memlimit_stop; 238 239 /** \private Reserved member. */ 240 uint64_t reserved_int7; 241 242 /** \private Reserved member. */ 243 uint64_t reserved_int8; 244 245 /** \private Reserved member. */ 246 void *reserved_ptr1; 247 248 /** \private Reserved member. */ 249 void *reserved_ptr2; 250 251 /** \private Reserved member. */ 252 void *reserved_ptr3; 253 254 /** \private Reserved member. */ 255 void *reserved_ptr4; 256 257 } lzma_mt; 258 259 260 /** 261 * \brief Calculate approximate memory usage of easy encoder 262 * 263 * This function is a wrapper for lzma_raw_encoder_memusage(). 264 * 265 * \param preset Compression preset (level and possible flags) 266 * 267 * \return Number of bytes of memory required for the given 268 * preset when encoding or UINT64_MAX on error. 269 */ 270 extern LZMA_API(uint64_t) lzma_easy_encoder_memusage(uint32_t preset) 271 lzma_nothrow lzma_attr_pure; 272 273 274 /** 275 * \brief Calculate approximate decoder memory usage of a preset 276 * 277 * This function is a wrapper for lzma_raw_decoder_memusage(). 278 * 279 * \param preset Compression preset (level and possible flags) 280 * 281 * \return Number of bytes of memory required to decompress a file 282 * that was compressed using the given preset or UINT64_MAX 283 * on error. 284 */ 285 extern LZMA_API(uint64_t) lzma_easy_decoder_memusage(uint32_t preset) 286 lzma_nothrow lzma_attr_pure; 287 288 289 /** 290 * \brief Initialize .xz Stream encoder using a preset number 291 * 292 * This function is intended for those who just want to use the basic features 293 * of liblzma (that is, most developers out there). 294 * 295 * If initialization fails (return value is not LZMA_OK), all the memory 296 * allocated for *strm by liblzma is always freed. Thus, there is no need 297 * to call lzma_end() after failed initialization. 298 * 299 * If initialization succeeds, use lzma_code() to do the actual encoding. 300 * Valid values for `action' (the second argument of lzma_code()) are 301 * LZMA_RUN, LZMA_SYNC_FLUSH, LZMA_FULL_FLUSH, and LZMA_FINISH. In future, 302 * there may be compression levels or flags that don't support LZMA_SYNC_FLUSH. 303 * 304 * \param strm Pointer to lzma_stream that is at least initialized 305 * with LZMA_STREAM_INIT. 306 * \param preset Compression preset to use. A preset consist of level 307 * number and zero or more flags. Usually flags aren't 308 * used, so preset is simply a number [0, 9] which match 309 * the options -0 ... -9 of the xz command line tool. 310 * Additional flags can be be set using bitwise-or with 311 * the preset level number, e.g. 6 | LZMA_PRESET_EXTREME. 312 * \param check Integrity check type to use. See check.h for available 313 * checks. The xz command line tool defaults to 314 * LZMA_CHECK_CRC64, which is a good choice if you are 315 * unsure. LZMA_CHECK_CRC32 is good too as long as the 316 * uncompressed file is not many gigabytes. 317 * 318 * \return Possible lzma_ret values: 319 * - LZMA_OK: Initialization succeeded. Use lzma_code() to 320 * encode your data. 321 * - LZMA_MEM_ERROR: Memory allocation failed. 322 * - LZMA_OPTIONS_ERROR: The given compression preset is not 323 * supported by this build of liblzma. 324 * - LZMA_UNSUPPORTED_CHECK: The given check type is not 325 * supported by this liblzma build. 326 * - LZMA_PROG_ERROR: One or more of the parameters have values 327 * that will never be valid. For example, strm == NULL. 328 */ 329 extern LZMA_API(lzma_ret) lzma_easy_encoder( 330 lzma_stream *strm, uint32_t preset, lzma_check check) 331 lzma_nothrow lzma_attr_warn_unused_result; 332 333 334 /** 335 * \brief Single-call .xz Stream encoding using a preset number 336 * 337 * The maximum required output buffer size can be calculated with 338 * lzma_stream_buffer_bound(). 339 * 340 * \param preset Compression preset to use. See the description 341 * in lzma_easy_encoder(). 342 * \param check Type of the integrity check to calculate from 343 * uncompressed data. 344 * \param allocator lzma_allocator for custom allocator functions. 345 * Set to NULL to use malloc() and free(). 346 * \param in Beginning of the input buffer 347 * \param in_size Size of the input buffer 348 * \param[out] out Beginning of the output buffer 349 * \param[out] out_pos The next byte will be written to out[*out_pos]. 350 * *out_pos is updated only if encoding succeeds. 351 * \param out_size Size of the out buffer; the first byte into 352 * which no data is written to is out[out_size]. 353 * 354 * \return Possible lzma_ret values: 355 * - LZMA_OK: Encoding was successful. 356 * - LZMA_BUF_ERROR: Not enough output buffer space. 357 * - LZMA_UNSUPPORTED_CHECK 358 * - LZMA_OPTIONS_ERROR 359 * - LZMA_MEM_ERROR 360 * - LZMA_DATA_ERROR 361 * - LZMA_PROG_ERROR 362 */ 363 extern LZMA_API(lzma_ret) lzma_easy_buffer_encode( 364 uint32_t preset, lzma_check check, 365 const lzma_allocator *allocator, 366 const uint8_t *in, size_t in_size, 367 uint8_t *out, size_t *out_pos, size_t out_size) lzma_nothrow; 368 369 370 /** 371 * \brief Initialize .xz Stream encoder using a custom filter chain 372 * 373 * \param strm Pointer to lzma_stream that is at least initialized 374 * with LZMA_STREAM_INIT. 375 * \param filters Array of filters terminated with 376 * .id == LZMA_VLI_UNKNOWN. See filters.h for more 377 * information. 378 * \param check Type of the integrity check to calculate from 379 * uncompressed data. 380 * 381 * \return Possible lzma_ret values: 382 * - LZMA_OK: Initialization was successful. 383 * - LZMA_MEM_ERROR 384 * - LZMA_UNSUPPORTED_CHECK 385 * - LZMA_OPTIONS_ERROR 386 * - LZMA_PROG_ERROR 387 */ 388 extern LZMA_API(lzma_ret) lzma_stream_encoder(lzma_stream *strm, 389 const lzma_filter *filters, lzma_check check) 390 lzma_nothrow lzma_attr_warn_unused_result; 391 392 393 /** 394 * \brief Calculate approximate memory usage of multithreaded .xz encoder 395 * 396 * Since doing the encoding in threaded mode doesn't affect the memory 397 * requirements of single-threaded decompressor, you can use 398 * lzma_easy_decoder_memusage(options->preset) or 399 * lzma_raw_decoder_memusage(options->filters) to calculate 400 * the decompressor memory requirements. 401 * 402 * \param options Compression options 403 * 404 * \return Number of bytes of memory required for encoding with the 405 * given options. If an error occurs, for example due to 406 * unsupported preset or filter chain, UINT64_MAX is returned. 407 */ 408 extern LZMA_API(uint64_t) lzma_stream_encoder_mt_memusage( 409 const lzma_mt *options) lzma_nothrow lzma_attr_pure; 410 411 412 /** 413 * \brief Initialize multithreaded .xz Stream encoder 414 * 415 * This provides the functionality of lzma_easy_encoder() and 416 * lzma_stream_encoder() as a single function for multithreaded use. 417 * 418 * The supported actions for lzma_code() are LZMA_RUN, LZMA_FULL_FLUSH, 419 * LZMA_FULL_BARRIER, and LZMA_FINISH. Support for LZMA_SYNC_FLUSH might be 420 * added in the future. 421 * 422 * \param strm Pointer to lzma_stream that is at least initialized 423 * with LZMA_STREAM_INIT. 424 * \param options Pointer to multithreaded compression options 425 * 426 * \return Possible lzma_ret values: 427 * - LZMA_OK 428 * - LZMA_MEM_ERROR 429 * - LZMA_UNSUPPORTED_CHECK 430 * - LZMA_OPTIONS_ERROR 431 * - LZMA_PROG_ERROR 432 */ 433 extern LZMA_API(lzma_ret) lzma_stream_encoder_mt( 434 lzma_stream *strm, const lzma_mt *options) 435 lzma_nothrow lzma_attr_warn_unused_result; 436 437 438 /** 439 * \brief Initialize .lzma encoder (legacy file format) 440 * 441 * The .lzma format is sometimes called the LZMA_Alone format, which is the 442 * reason for the name of this function. The .lzma format supports only the 443 * LZMA1 filter. There is no support for integrity checks like CRC32. 444 * 445 * Use this function if and only if you need to create files readable by 446 * legacy LZMA tools such as LZMA Utils 4.32.x. Moving to the .xz format 447 * is strongly recommended. 448 * 449 * The valid action values for lzma_code() are LZMA_RUN and LZMA_FINISH. 450 * No kind of flushing is supported, because the file format doesn't make 451 * it possible. 452 * 453 * \param strm Pointer to lzma_stream that is at least initialized 454 * with LZMA_STREAM_INIT. 455 * \param options Pointer to encoder options 456 * 457 * \return Possible lzma_ret values: 458 * - LZMA_OK 459 * - LZMA_MEM_ERROR 460 * - LZMA_OPTIONS_ERROR 461 * - LZMA_PROG_ERROR 462 */ 463 extern LZMA_API(lzma_ret) lzma_alone_encoder( 464 lzma_stream *strm, const lzma_options_lzma *options) 465 lzma_nothrow lzma_attr_warn_unused_result; 466 467 468 /** 469 * \brief Calculate output buffer size for single-call Stream encoder 470 * 471 * When trying to compress incompressible data, the encoded size will be 472 * slightly bigger than the input data. This function calculates how much 473 * output buffer space is required to be sure that lzma_stream_buffer_encode() 474 * doesn't return LZMA_BUF_ERROR. 475 * 476 * The calculated value is not exact, but it is guaranteed to be big enough. 477 * The actual maximum output space required may be slightly smaller (up to 478 * about 100 bytes). This should not be a problem in practice. 479 * 480 * If the calculated maximum size doesn't fit into size_t or would make the 481 * Stream grow past LZMA_VLI_MAX (which should never happen in practice), 482 * zero is returned to indicate the error. 483 * 484 * \note The limit calculated by this function applies only to 485 * single-call encoding. Multi-call encoding may (and probably 486 * will) have larger maximum expansion when encoding 487 * incompressible data. Currently there is no function to 488 * calculate the maximum expansion of multi-call encoding. 489 * 490 * \param uncompressed_size Size in bytes of the uncompressed 491 * input data 492 * 493 * \return Maximum number of bytes needed to store the compressed data. 494 */ 495 extern LZMA_API(size_t) lzma_stream_buffer_bound(size_t uncompressed_size) 496 lzma_nothrow; 497 498 499 /** 500 * \brief Single-call .xz Stream encoder 501 * 502 * \param filters Array of filters terminated with 503 * .id == LZMA_VLI_UNKNOWN. See filters.h for more 504 * information. 505 * \param check Type of the integrity check to calculate from 506 * uncompressed data. 507 * \param allocator lzma_allocator for custom allocator functions. 508 * Set to NULL to use malloc() and free(). 509 * \param in Beginning of the input buffer 510 * \param in_size Size of the input buffer 511 * \param[out] out Beginning of the output buffer 512 * \param[out] out_pos The next byte will be written to out[*out_pos]. 513 * *out_pos is updated only if encoding succeeds. 514 * \param out_size Size of the out buffer; the first byte into 515 * which no data is written to is out[out_size]. 516 * 517 * \return Possible lzma_ret values: 518 * - LZMA_OK: Encoding was successful. 519 * - LZMA_BUF_ERROR: Not enough output buffer space. 520 * - LZMA_UNSUPPORTED_CHECK 521 * - LZMA_OPTIONS_ERROR 522 * - LZMA_MEM_ERROR 523 * - LZMA_DATA_ERROR 524 * - LZMA_PROG_ERROR 525 */ 526 extern LZMA_API(lzma_ret) lzma_stream_buffer_encode( 527 lzma_filter *filters, lzma_check check, 528 const lzma_allocator *allocator, 529 const uint8_t *in, size_t in_size, 530 uint8_t *out, size_t *out_pos, size_t out_size) 531 lzma_nothrow lzma_attr_warn_unused_result; 532 533 534 /** 535 * \brief MicroLZMA encoder 536 * 537 * The MicroLZMA format is a raw LZMA stream whose first byte (always 0x00) 538 * has been replaced with bitwise-negation of the LZMA properties (lc/lp/pb). 539 * This encoding ensures that the first byte of MicroLZMA stream is never 540 * 0x00. There is no end of payload marker and thus the uncompressed size 541 * must be stored separately. For the best error detection the dictionary 542 * size should be stored separately as well but alternatively one may use 543 * the uncompressed size as the dictionary size when decoding. 544 * 545 * With the MicroLZMA encoder, lzma_code() behaves slightly unusually. 546 * The action argument must be LZMA_FINISH and the return value will never be 547 * LZMA_OK. Thus the encoding is always done with a single lzma_code() after 548 * the initialization. The benefit of the combination of initialization 549 * function and lzma_code() is that memory allocations can be re-used for 550 * better performance. 551 * 552 * lzma_code() will try to encode as much input as is possible to fit into 553 * the given output buffer. If not all input can be encoded, the stream will 554 * be finished without encoding all the input. The caller must check both 555 * input and output buffer usage after lzma_code() (total_in and total_out 556 * in lzma_stream can be convenient). Often lzma_code() can fill the output 557 * buffer completely if there is a lot of input, but sometimes a few bytes 558 * may remain unused because the next LZMA symbol would require more space. 559 * 560 * lzma_stream.avail_out must be at least 6. Otherwise LZMA_PROG_ERROR 561 * will be returned. 562 * 563 * The LZMA dictionary should be reasonably low to speed up the encoder 564 * re-initialization. A good value is bigger than the resulting 565 * uncompressed size of most of the output chunks. For example, if output 566 * size is 4 KiB, dictionary size of 32 KiB or 64 KiB is good. If the 567 * data compresses extremely well, even 128 KiB may be useful. 568 * 569 * The MicroLZMA format and this encoder variant were made with the EROFS 570 * file system in mind. This format may be convenient in other embedded 571 * uses too where many small streams are needed. XZ Embedded includes a 572 * decoder for this format. 573 * 574 * \param strm Pointer to lzma_stream that is at least initialized 575 * with LZMA_STREAM_INIT. 576 * \param options Pointer to encoder options 577 * 578 * \return Possible lzma_ret values: 579 * - LZMA_STREAM_END: All good. Check the amounts of input used 580 * and output produced. Store the amount of input used 581 * (uncompressed size) as it needs to be known to decompress 582 * the data. 583 * - LZMA_OPTIONS_ERROR 584 * - LZMA_MEM_ERROR 585 * - LZMA_PROG_ERROR: In addition to the generic reasons for this 586 * error code, this may also be returned if there isn't enough 587 * output space (6 bytes) to create a valid MicroLZMA stream. 588 */ 589 extern LZMA_API(lzma_ret) lzma_microlzma_encoder( 590 lzma_stream *strm, const lzma_options_lzma *options) 591 lzma_nothrow; 592 593 594 /************ 595 * Decoding * 596 ************/ 597 598 /** 599 * This flag makes lzma_code() return LZMA_NO_CHECK if the input stream 600 * being decoded has no integrity check. Note that when used with 601 * lzma_auto_decoder(), all .lzma files will trigger LZMA_NO_CHECK 602 * if LZMA_TELL_NO_CHECK is used. 603 */ 604 #define LZMA_TELL_NO_CHECK UINT32_C(0x01) 605 606 607 /** 608 * This flag makes lzma_code() return LZMA_UNSUPPORTED_CHECK if the input 609 * stream has an integrity check, but the type of the integrity check is not 610 * supported by this liblzma version or build. Such files can still be 611 * decoded, but the integrity check cannot be verified. 612 */ 613 #define LZMA_TELL_UNSUPPORTED_CHECK UINT32_C(0x02) 614 615 616 /** 617 * This flag makes lzma_code() return LZMA_GET_CHECK as soon as the type 618 * of the integrity check is known. The type can then be got with 619 * lzma_get_check(). 620 */ 621 #define LZMA_TELL_ANY_CHECK UINT32_C(0x04) 622 623 624 /** 625 * This flag makes lzma_code() not calculate and verify the integrity check 626 * of the compressed data in .xz files. This means that invalid integrity 627 * check values won't be detected and LZMA_DATA_ERROR won't be returned in 628 * such cases. 629 * 630 * This flag only affects the checks of the compressed data itself; the CRC32 631 * values in the .xz headers will still be verified normally. 632 * 633 * Don't use this flag unless you know what you are doing. Possible reasons 634 * to use this flag: 635 * 636 * - Trying to recover data from a corrupt .xz file. 637 * 638 * - Speeding up decompression, which matters mostly with SHA-256 639 * or with files that have compressed extremely well. It's recommended 640 * to not use this flag for this purpose unless the file integrity is 641 * verified externally in some other way. 642 * 643 * Support for this flag was added in liblzma 5.1.4beta. 644 */ 645 #define LZMA_IGNORE_CHECK UINT32_C(0x10) 646 647 648 /** 649 * This flag enables decoding of concatenated files with file formats that 650 * allow concatenating compressed files as is. From the formats currently 651 * supported by liblzma, only the .xz and .lz formats allow concatenated 652 * files. Concatenated files are not allowed with the legacy .lzma format. 653 * 654 * This flag also affects the usage of the `action' argument for lzma_code(). 655 * When LZMA_CONCATENATED is used, lzma_code() won't return LZMA_STREAM_END 656 * unless LZMA_FINISH is used as `action'. Thus, the application has to set 657 * LZMA_FINISH in the same way as it does when encoding. 658 * 659 * If LZMA_CONCATENATED is not used, the decoders still accept LZMA_FINISH 660 * as `action' for lzma_code(), but the usage of LZMA_FINISH isn't required. 661 */ 662 #define LZMA_CONCATENATED UINT32_C(0x08) 663 664 665 /** 666 * This flag makes the threaded decoder report errors (like LZMA_DATA_ERROR) 667 * as soon as they are detected. This saves time when the application has no 668 * interest in a partially decompressed truncated or corrupt file. Note that 669 * due to timing randomness, if the same truncated or corrupt input is 670 * decompressed multiple times with this flag, a different amount of output 671 * may be produced by different runs, and even the error code might vary. 672 * 673 * When using LZMA_FAIL_FAST, it is recommended to use LZMA_FINISH to tell 674 * the decoder when no more input will be coming because it can help fast 675 * detection and reporting of truncated files. Note that in this situation 676 * truncated files might be diagnosed with LZMA_DATA_ERROR instead of 677 * LZMA_OK or LZMA_BUF_ERROR! 678 * 679 * Without this flag the threaded decoder will provide as much output as 680 * possible at first and then report the pending error. This default behavior 681 * matches the single-threaded decoder and provides repeatable behavior 682 * with truncated or corrupt input. There are a few special cases where the 683 * behavior can still differ like memory allocation failures (LZMA_MEM_ERROR). 684 * 685 * Single-threaded decoders currently ignore this flag. 686 * 687 * Support for this flag was added in liblzma 5.3.3alpha. Note that in older 688 * versions this flag isn't supported (LZMA_OPTIONS_ERROR) even by functions 689 * that ignore this flag in newer liblzma versions. 690 */ 691 #define LZMA_FAIL_FAST UINT32_C(0x20) 692 693 694 /** 695 * \brief Initialize .xz Stream decoder 696 * 697 * \param strm Pointer to lzma_stream that is at least initialized 698 * with LZMA_STREAM_INIT. 699 * \param memlimit Memory usage limit as bytes. Use UINT64_MAX 700 * to effectively disable the limiter. liblzma 701 * 5.2.3 and earlier don't allow 0 here and return 702 * LZMA_PROG_ERROR; later versions treat 0 as if 1 703 * had been specified. 704 * \param flags Bitwise-or of zero or more of the decoder flags: 705 * LZMA_TELL_NO_CHECK, LZMA_TELL_UNSUPPORTED_CHECK, 706 * LZMA_TELL_ANY_CHECK, LZMA_IGNORE_CHECK, 707 * LZMA_CONCATENATED, LZMA_FAIL_FAST 708 * 709 * \return Possible lzma_ret values: 710 * - LZMA_OK: Initialization was successful. 711 * - LZMA_MEM_ERROR: Cannot allocate memory. 712 * - LZMA_OPTIONS_ERROR: Unsupported flags 713 * - LZMA_PROG_ERROR 714 */ 715 extern LZMA_API(lzma_ret) lzma_stream_decoder( 716 lzma_stream *strm, uint64_t memlimit, uint32_t flags) 717 lzma_nothrow lzma_attr_warn_unused_result; 718 719 720 /** 721 * \brief Initialize multithreaded .xz Stream decoder 722 * 723 * The decoder can decode multiple Blocks in parallel. This requires that each 724 * Block Header contains the Compressed Size and Uncompressed size fields 725 * which are added by the multi-threaded encoder, see lzma_stream_encoder_mt(). 726 * 727 * A Stream with one Block will only utilize one thread. A Stream with multiple 728 * Blocks but without size information in Block Headers will be processed in 729 * single-threaded mode in the same way as done by lzma_stream_decoder(). 730 * Concatenated Streams are processed one Stream at a time; no inter-Stream 731 * parallelization is done. 732 * 733 * This function behaves like lzma_stream_decoder() when options->threads == 1 734 * and options->memlimit_threading <= 1. 735 * 736 * \param strm Pointer to lzma_stream that is at least initialized 737 * with LZMA_STREAM_INIT. 738 * \param options Pointer to multithreaded compression options 739 * 740 * \return Possible lzma_ret values: 741 * - LZMA_OK: Initialization was successful. 742 * - LZMA_MEM_ERROR: Cannot allocate memory. 743 * - LZMA_MEMLIMIT_ERROR: Memory usage limit was reached. 744 * - LZMA_OPTIONS_ERROR: Unsupported flags. 745 * - LZMA_PROG_ERROR 746 */ 747 extern LZMA_API(lzma_ret) lzma_stream_decoder_mt( 748 lzma_stream *strm, const lzma_mt *options) 749 lzma_nothrow lzma_attr_warn_unused_result; 750 751 752 /** 753 * \brief Decode .xz, .lzma, and .lz (lzip) files with autodetection 754 * 755 * This decoder autodetects between the .xz, .lzma, and .lz file formats, 756 * and calls lzma_stream_decoder(), lzma_alone_decoder(), or 757 * lzma_lzip_decoder() once the type of the input file has been detected. 758 * 759 * Support for .lz was added in 5.4.0. 760 * 761 * If the flag LZMA_CONCATENATED is used and the input is a .lzma file: 762 * For historical reasons concatenated .lzma files aren't supported. 763 * If there is trailing data after one .lzma stream, lzma_code() will 764 * return LZMA_DATA_ERROR. (lzma_alone_decoder() doesn't have such a check 765 * as it doesn't support any decoder flags. It will return LZMA_STREAM_END 766 * after one .lzma stream.) 767 * 768 * \param strm Pointer to lzma_stream that is at least initialized 769 * with LZMA_STREAM_INIT. 770 * \param memlimit Memory usage limit as bytes. Use UINT64_MAX 771 * to effectively disable the limiter. liblzma 772 * 5.2.3 and earlier don't allow 0 here and return 773 * LZMA_PROG_ERROR; later versions treat 0 as if 1 774 * had been specified. 775 * \param flags Bitwise-or of zero or more of the decoder flags: 776 * LZMA_TELL_NO_CHECK, LZMA_TELL_UNSUPPORTED_CHECK, 777 * LZMA_TELL_ANY_CHECK, LZMA_IGNORE_CHECK, 778 * LZMA_CONCATENATED, LZMA_FAIL_FAST 779 * 780 * \return Possible lzma_ret values: 781 * - LZMA_OK: Initialization was successful. 782 * - LZMA_MEM_ERROR: Cannot allocate memory. 783 * - LZMA_OPTIONS_ERROR: Unsupported flags 784 * - LZMA_PROG_ERROR 785 */ 786 extern LZMA_API(lzma_ret) lzma_auto_decoder( 787 lzma_stream *strm, uint64_t memlimit, uint32_t flags) 788 lzma_nothrow lzma_attr_warn_unused_result; 789 790 791 /** 792 * \brief Initialize .lzma decoder (legacy file format) 793 * 794 * Valid `action' arguments to lzma_code() are LZMA_RUN and LZMA_FINISH. 795 * There is no need to use LZMA_FINISH, but it's allowed because it may 796 * simplify certain types of applications. 797 * 798 * \param strm Pointer to lzma_stream that is at least initialized 799 * with LZMA_STREAM_INIT. 800 * \param memlimit Memory usage limit as bytes. Use UINT64_MAX 801 * to effectively disable the limiter. liblzma 802 * 5.2.3 and earlier don't allow 0 here and return 803 * LZMA_PROG_ERROR; later versions treat 0 as if 1 804 * had been specified. 805 * 806 * \return Possible lzma_ret values: 807 * - LZMA_OK 808 * - LZMA_MEM_ERROR 809 * - LZMA_PROG_ERROR 810 */ 811 extern LZMA_API(lzma_ret) lzma_alone_decoder( 812 lzma_stream *strm, uint64_t memlimit) 813 lzma_nothrow lzma_attr_warn_unused_result; 814 815 816 /** 817 * \brief Initialize .lz (lzip) decoder (a foreign file format) 818 * 819 * This decoder supports the .lz format version 0 and the unextended .lz 820 * format version 1: 821 * 822 * - Files in the format version 0 were produced by lzip 1.3 and older. 823 * Such files aren't common but may be found from file archives 824 * as a few source packages were released in this format. People 825 * might have old personal files in this format too. Decompression 826 * support for the format version 0 was removed in lzip 1.18. 827 * 828 * - lzip 1.3 added decompression support for .lz format version 1 files. 829 * Compression support was added in lzip 1.4. In lzip 1.6 the .lz format 830 * version 1 was extended to support the Sync Flush marker. This extension 831 * is not supported by liblzma. lzma_code() will return LZMA_DATA_ERROR 832 * at the location of the Sync Flush marker. In practice files with 833 * the Sync Flush marker are very rare and thus liblzma can decompress 834 * almost all .lz files. 835 * 836 * Just like with lzma_stream_decoder() for .xz files, LZMA_CONCATENATED 837 * should be used when decompressing normal standalone .lz files. 838 * 839 * The .lz format allows putting non-.lz data at the end of a file after at 840 * least one valid .lz member. That is, one can append custom data at the end 841 * of a .lz file and the decoder is required to ignore it. In liblzma this 842 * is relevant only when LZMA_CONCATENATED is used. In that case lzma_code() 843 * will return LZMA_STREAM_END and leave lzma_stream.next_in pointing to 844 * the first byte of the non-.lz data. An exception to this is if the first 845 * 1-3 bytes of the non-.lz data are identical to the .lz magic bytes 846 * (0x4C, 0x5A, 0x49, 0x50; "LZIP" in US-ASCII). In such a case the 1-3 bytes 847 * will have been ignored by lzma_code(). If one wishes to locate the non-.lz 848 * data reliably, one must ensure that the first byte isn't 0x4C. Actually 849 * one should ensure that none of the first four bytes of trailing data are 850 * equal to the magic bytes because lzip >= 1.20 requires it by default. 851 * 852 * \param strm Pointer to lzma_stream that is at least initialized 853 * with LZMA_STREAM_INIT. 854 * \param memlimit Memory usage limit as bytes. Use UINT64_MAX 855 * to effectively disable the limiter. 856 * \param flags Bitwise-or of flags, or zero for no flags. 857 * All decoder flags listed above are supported 858 * although only LZMA_CONCATENATED and (in very rare 859 * cases) LZMA_IGNORE_CHECK are actually useful. 860 * LZMA_TELL_NO_CHECK, LZMA_TELL_UNSUPPORTED_CHECK, 861 * and LZMA_FAIL_FAST do nothing. LZMA_TELL_ANY_CHECK 862 * is supported for consistency only as CRC32 is 863 * always used in the .lz format. 864 * 865 * \return Possible lzma_ret values: 866 * - LZMA_OK: Initialization was successful. 867 * - LZMA_MEM_ERROR: Cannot allocate memory. 868 * - LZMA_OPTIONS_ERROR: Unsupported flags 869 * - LZMA_PROG_ERROR 870 */ 871 extern LZMA_API(lzma_ret) lzma_lzip_decoder( 872 lzma_stream *strm, uint64_t memlimit, uint32_t flags) 873 lzma_nothrow lzma_attr_warn_unused_result; 874 875 876 /** 877 * \brief Single-call .xz Stream decoder 878 * 879 * \param memlimit Pointer to how much memory the decoder is allowed 880 * to allocate. The value pointed by this pointer is 881 * modified if and only if LZMA_MEMLIMIT_ERROR is 882 * returned. 883 * \param flags Bitwise-or of zero or more of the decoder flags: 884 * LZMA_TELL_NO_CHECK, LZMA_TELL_UNSUPPORTED_CHECK, 885 * LZMA_IGNORE_CHECK, LZMA_CONCATENATED, 886 * LZMA_FAIL_FAST. Note that LZMA_TELL_ANY_CHECK 887 * is not allowed and will return LZMA_PROG_ERROR. 888 * \param allocator lzma_allocator for custom allocator functions. 889 * Set to NULL to use malloc() and free(). 890 * \param in Beginning of the input buffer 891 * \param in_pos The next byte will be read from in[*in_pos]. 892 * *in_pos is updated only if decoding succeeds. 893 * \param in_size Size of the input buffer; the first byte that 894 * won't be read is in[in_size]. 895 * \param[out] out Beginning of the output buffer 896 * \param[out] out_pos The next byte will be written to out[*out_pos]. 897 * *out_pos is updated only if decoding succeeds. 898 * \param out_size Size of the out buffer; the first byte into 899 * which no data is written to is out[out_size]. 900 * 901 * \return Possible lzma_ret values: 902 * - LZMA_OK: Decoding was successful. 903 * - LZMA_FORMAT_ERROR 904 * - LZMA_OPTIONS_ERROR 905 * - LZMA_DATA_ERROR 906 * - LZMA_NO_CHECK: This can be returned only if using 907 * the LZMA_TELL_NO_CHECK flag. 908 * - LZMA_UNSUPPORTED_CHECK: This can be returned only if using 909 * the LZMA_TELL_UNSUPPORTED_CHECK flag. 910 * - LZMA_MEM_ERROR 911 * - LZMA_MEMLIMIT_ERROR: Memory usage limit was reached. 912 * The minimum required memlimit value was stored to *memlimit. 913 * - LZMA_BUF_ERROR: Output buffer was too small. 914 * - LZMA_PROG_ERROR 915 */ 916 extern LZMA_API(lzma_ret) lzma_stream_buffer_decode( 917 uint64_t *memlimit, uint32_t flags, 918 const lzma_allocator *allocator, 919 const uint8_t *in, size_t *in_pos, size_t in_size, 920 uint8_t *out, size_t *out_pos, size_t out_size) 921 lzma_nothrow lzma_attr_warn_unused_result; 922 923 924 /** 925 * \brief MicroLZMA decoder 926 * 927 * See lzma_microlzma_encoder() for more information. 928 * 929 * The lzma_code() usage with this decoder is completely normal. The 930 * special behavior of lzma_code() applies to lzma_microlzma_encoder() only. 931 * 932 * \param strm Pointer to lzma_stream that is at least initialized 933 * with LZMA_STREAM_INIT. 934 * \param comp_size Compressed size of the MicroLZMA stream. 935 * The caller must somehow know this exactly. 936 * \param uncomp_size Uncompressed size of the MicroLZMA stream. 937 * If the exact uncompressed size isn't known, this 938 * can be set to a value that is at most as big as 939 * the exact uncompressed size would be, but then the 940 * next argument uncomp_size_is_exact must be false. 941 * \param uncomp_size_is_exact 942 * If true, uncomp_size must be exactly correct. 943 * This will improve error detection at the end of 944 * the stream. If the exact uncompressed size isn't 945 * known, this must be false. uncomp_size must still 946 * be at most as big as the exact uncompressed size 947 * is. Setting this to false when the exact size is 948 * known will work but error detection at the end of 949 * the stream will be weaker. 950 * \param dict_size LZMA dictionary size that was used when 951 * compressing the data. It is OK to use a bigger 952 * value too but liblzma will then allocate more 953 * memory than would actually be required and error 954 * detection will be slightly worse. (Note that with 955 * the implementation in XZ Embedded it doesn't 956 * affect the memory usage if one specifies bigger 957 * dictionary than actually required.) 958 * 959 * \return Possible lzma_ret values: 960 * - LZMA_OK 961 * - LZMA_MEM_ERROR 962 * - LZMA_OPTIONS_ERROR 963 * - LZMA_PROG_ERROR 964 */ 965 extern LZMA_API(lzma_ret) lzma_microlzma_decoder( 966 lzma_stream *strm, uint64_t comp_size, 967 uint64_t uncomp_size, lzma_bool uncomp_size_is_exact, 968 uint32_t dict_size) lzma_nothrow; 969