1 /** 2 * \file lzma/base.h 3 * \brief Data types and functions used in many places in liblzma API 4 */ 5 6 /* 7 * Author: Lasse Collin 8 * 9 * This file has been put into the public domain. 10 * You can do whatever you want with this file. 11 * 12 * See ../lzma.h for information about liblzma as a whole. 13 */ 14 15 #ifndef LZMA_H_INTERNAL 16 # error Never include this file directly. Use <lzma.h> instead. 17 #endif 18 19 20 /** 21 * \brief Boolean 22 * 23 * This is here because C89 doesn't have stdbool.h. To set a value for 24 * variables having type lzma_bool, you can use 25 * - C99's `true' and `false' from stdbool.h; 26 * - C++'s internal `true' and `false'; or 27 * - integers one (true) and zero (false). 28 */ 29 typedef unsigned char lzma_bool; 30 31 32 /** 33 * \brief Type of reserved enumeration variable in structures 34 * 35 * To avoid breaking library ABI when new features are added, several 36 * structures contain extra variables that may be used in future. Since 37 * sizeof(enum) can be different than sizeof(int), and sizeof(enum) may 38 * even vary depending on the range of enumeration constants, we specify 39 * a separate type to be used for reserved enumeration variables. All 40 * enumeration constants in liblzma API will be non-negative and less 41 * than 128, which should guarantee that the ABI won't break even when 42 * new constants are added to existing enumerations. 43 */ 44 typedef enum { 45 LZMA_RESERVED_ENUM = 0 46 } lzma_reserved_enum; 47 48 49 /** 50 * \brief Return values used by several functions in liblzma 51 * 52 * Check the descriptions of specific functions to find out which return 53 * values they can return. With some functions the return values may have 54 * more specific meanings than described here; those differences are 55 * described per-function basis. 56 */ 57 typedef enum { 58 LZMA_OK = 0, 59 /**< 60 * \brief Operation completed successfully 61 */ 62 63 LZMA_STREAM_END = 1, 64 /**< 65 * \brief End of stream was reached 66 * 67 * In encoder, LZMA_SYNC_FLUSH, LZMA_FULL_FLUSH, or 68 * LZMA_FINISH was finished. In decoder, this indicates 69 * that all the data was successfully decoded. 70 * 71 * In all cases, when LZMA_STREAM_END is returned, the last 72 * output bytes should be picked from strm->next_out. 73 */ 74 75 LZMA_NO_CHECK = 2, 76 /**< 77 * \brief Input stream has no integrity check 78 * 79 * This return value can be returned only if the 80 * LZMA_TELL_NO_CHECK flag was used when initializing 81 * the decoder. LZMA_NO_CHECK is just a warning, and 82 * the decoding can be continued normally. 83 * 84 * It is possible to call lzma_get_check() immediately after 85 * lzma_code has returned LZMA_NO_CHECK. The result will 86 * naturally be LZMA_CHECK_NONE, but the possibility to call 87 * lzma_get_check() may be convenient in some applications. 88 */ 89 90 LZMA_UNSUPPORTED_CHECK = 3, 91 /**< 92 * \brief Cannot calculate the integrity check 93 * 94 * The usage of this return value is different in encoders 95 * and decoders. 96 * 97 * Encoders can return this value only from the initialization 98 * function. If initialization fails with this value, the 99 * encoding cannot be done, because there's no way to produce 100 * output with the correct integrity check. 101 * 102 * Decoders can return this value only from lzma_code() and 103 * only if the LZMA_TELL_UNSUPPORTED_CHECK flag was used when 104 * initializing the decoder. The decoding can still be 105 * continued normally even if the check type is unsupported, 106 * but naturally the check will not be validated, and possible 107 * errors may go undetected. 108 * 109 * With decoder, it is possible to call lzma_get_check() 110 * immediately after lzma_code() has returned 111 * LZMA_UNSUPPORTED_CHECK. This way it is possible to find 112 * out what the unsupported Check ID was. 113 */ 114 115 LZMA_GET_CHECK = 4, 116 /**< 117 * \brief Integrity check type is now available 118 * 119 * This value can be returned only by the lzma_code() function 120 * and only if the decoder was initialized with the 121 * LZMA_TELL_ANY_CHECK flag. LZMA_GET_CHECK tells the 122 * application that it may now call lzma_get_check() to find 123 * out the Check ID. This can be used, for example, to 124 * implement a decoder that accepts only files that have 125 * strong enough integrity check. 126 */ 127 128 LZMA_MEM_ERROR = 5, 129 /**< 130 * \brief Cannot allocate memory 131 * 132 * Memory allocation failed, or the size of the allocation 133 * would be greater than SIZE_MAX. 134 * 135 * Due to internal implementation reasons, the coding cannot 136 * be continued even if more memory were made available after 137 * LZMA_MEM_ERROR. 138 */ 139 140 LZMA_MEMLIMIT_ERROR = 6, 141 /** 142 * \brief Memory usage limit was reached 143 * 144 * Decoder would need more memory than allowed by the 145 * specified memory usage limit. To continue decoding, 146 * the memory usage limit has to be increased with 147 * lzma_memlimit_set(). 148 */ 149 150 LZMA_FORMAT_ERROR = 7, 151 /**< 152 * \brief File format not recognized 153 * 154 * The decoder did not recognize the input as supported file 155 * format. This error can occur, for example, when trying to 156 * decode .lzma format file with lzma_stream_decoder, 157 * because lzma_stream_decoder accepts only the .xz format. 158 */ 159 160 LZMA_OPTIONS_ERROR = 8, 161 /**< 162 * \brief Invalid or unsupported options 163 * 164 * Invalid or unsupported options, for example 165 * - unsupported filter(s) or filter options; or 166 * - reserved bits set in headers (decoder only). 167 * 168 * Rebuilding liblzma with more features enabled, or 169 * upgrading to a newer version of liblzma may help. 170 */ 171 172 LZMA_DATA_ERROR = 9, 173 /**< 174 * \brief Data is corrupt 175 * 176 * The usage of this return value is different in encoders 177 * and decoders. In both encoder and decoder, the coding 178 * cannot continue after this error. 179 * 180 * Encoders return this if size limits of the target file 181 * format would be exceeded. These limits are huge, thus 182 * getting this error from an encoder is mostly theoretical. 183 * For example, the maximum compressed and uncompressed 184 * size of a .xz Stream is roughly 8 EiB (2^63 bytes). 185 * 186 * Decoders return this error if the input data is corrupt. 187 * This can mean, for example, invalid CRC32 in headers 188 * or invalid check of uncompressed data. 189 */ 190 191 LZMA_BUF_ERROR = 10, 192 /**< 193 * \brief No progress is possible 194 * 195 * This error code is returned when the coder cannot consume 196 * any new input and produce any new output. The most common 197 * reason for this error is that the input stream being 198 * decoded is truncated or corrupt. 199 * 200 * This error is not fatal. Coding can be continued normally 201 * by providing more input and/or more output space, if 202 * possible. 203 * 204 * Typically the first call to lzma_code() that can do no 205 * progress returns LZMA_OK instead of LZMA_BUF_ERROR. Only 206 * the second consecutive call doing no progress will return 207 * LZMA_BUF_ERROR. This is intentional. 208 * 209 * With zlib, Z_BUF_ERROR may be returned even if the 210 * application is doing nothing wrong, so apps will need 211 * to handle Z_BUF_ERROR specially. The above hack 212 * guarantees that liblzma never returns LZMA_BUF_ERROR 213 * to properly written applications unless the input file 214 * is truncated or corrupt. This should simplify the 215 * applications a little. 216 */ 217 218 LZMA_PROG_ERROR = 11, 219 /**< 220 * \brief Programming error 221 * 222 * This indicates that the arguments given to the function are 223 * invalid or the internal state of the decoder is corrupt. 224 * - Function arguments are invalid or the structures 225 * pointed by the argument pointers are invalid 226 * e.g. if strm->next_out has been set to NULL and 227 * strm->avail_out > 0 when calling lzma_code(). 228 * - lzma_* functions have been called in wrong order 229 * e.g. lzma_code() was called right after lzma_end(). 230 * - If errors occur randomly, the reason might be flaky 231 * hardware. 232 * 233 * If you think that your code is correct, this error code 234 * can be a sign of a bug in liblzma. See the documentation 235 * how to report bugs. 236 */ 237 } lzma_ret; 238 239 240 /** 241 * \brief The `action' argument for lzma_code() 242 * 243 * After the first use of LZMA_SYNC_FLUSH, LZMA_FULL_FLUSH, LZMA_FULL_BARRIER, 244 * or LZMA_FINISH, the same `action' must is used until lzma_code() returns 245 * LZMA_STREAM_END. Also, the amount of input (that is, strm->avail_in) must 246 * not be modified by the application until lzma_code() returns 247 * LZMA_STREAM_END. Changing the `action' or modifying the amount of input 248 * will make lzma_code() return LZMA_PROG_ERROR. 249 */ 250 typedef enum { 251 LZMA_RUN = 0, 252 /**< 253 * \brief Continue coding 254 * 255 * Encoder: Encode as much input as possible. Some internal 256 * buffering will probably be done (depends on the filter 257 * chain in use), which causes latency: the input used won't 258 * usually be decodeable from the output of the same 259 * lzma_code() call. 260 * 261 * Decoder: Decode as much input as possible and produce as 262 * much output as possible. 263 */ 264 265 LZMA_SYNC_FLUSH = 1, 266 /**< 267 * \brief Make all the input available at output 268 * 269 * Normally the encoder introduces some latency. 270 * LZMA_SYNC_FLUSH forces all the buffered data to be 271 * available at output without resetting the internal 272 * state of the encoder. This way it is possible to use 273 * compressed stream for example for communication over 274 * network. 275 * 276 * Only some filters support LZMA_SYNC_FLUSH. Trying to use 277 * LZMA_SYNC_FLUSH with filters that don't support it will 278 * make lzma_code() return LZMA_OPTIONS_ERROR. For example, 279 * LZMA1 doesn't support LZMA_SYNC_FLUSH but LZMA2 does. 280 * 281 * Using LZMA_SYNC_FLUSH very often can dramatically reduce 282 * the compression ratio. With some filters (for example, 283 * LZMA2), fine-tuning the compression options may help 284 * mitigate this problem significantly (for example, 285 * match finder with LZMA2). 286 * 287 * Decoders don't support LZMA_SYNC_FLUSH. 288 */ 289 290 LZMA_FULL_FLUSH = 2, 291 /**< 292 * \brief Finish encoding of the current Block 293 * 294 * All the input data going to the current Block must have 295 * been given to the encoder (the last bytes can still be 296 * pending in *next_in). Call lzma_code() with LZMA_FULL_FLUSH 297 * until it returns LZMA_STREAM_END. Then continue normally 298 * with LZMA_RUN or finish the Stream with LZMA_FINISH. 299 * 300 * This action is currently supported only by Stream encoder 301 * and easy encoder (which uses Stream encoder). If there is 302 * no unfinished Block, no empty Block is created. 303 */ 304 305 LZMA_FULL_BARRIER = 4, 306 /**< 307 * \brief Finish encoding of the current Block 308 * 309 * This is like LZMA_FULL_FLUSH except that this doesn't 310 * necessarily wait until all the input has been made 311 * available via the output buffer. That is, lzma_code() 312 * might return LZMA_STREAM_END as soon as all the input 313 * has been consumed (avail_in == 0). 314 * 315 * LZMA_FULL_BARRIER is useful with a threaded encoder if 316 * one wants to split the .xz Stream into Blocks at specific 317 * offsets but doesn't care if the output isn't flushed 318 * immediately. Using LZMA_FULL_BARRIER allows keeping 319 * the threads busy while LZMA_FULL_FLUSH would make 320 * lzma_code() wait until all the threads have finished 321 * until more data could be passed to the encoder. 322 * 323 * With a lzma_stream initialized with the single-threaded 324 * lzma_stream_encoder() or lzma_easy_encoder(), 325 * LZMA_FULL_BARRIER is an alias for LZMA_FULL_FLUSH. 326 */ 327 328 LZMA_FINISH = 3 329 /**< 330 * \brief Finish the coding operation 331 * 332 * All the input data must have been given to the encoder 333 * (the last bytes can still be pending in next_in). 334 * Call lzma_code() with LZMA_FINISH until it returns 335 * LZMA_STREAM_END. Once LZMA_FINISH has been used, 336 * the amount of input must no longer be changed by 337 * the application. 338 * 339 * When decoding, using LZMA_FINISH is optional unless the 340 * LZMA_CONCATENATED flag was used when the decoder was 341 * initialized. When LZMA_CONCATENATED was not used, the only 342 * effect of LZMA_FINISH is that the amount of input must not 343 * be changed just like in the encoder. 344 */ 345 } lzma_action; 346 347 348 /** 349 * \brief Custom functions for memory handling 350 * 351 * A pointer to lzma_allocator may be passed via lzma_stream structure 352 * to liblzma, and some advanced functions take a pointer to lzma_allocator 353 * as a separate function argument. The library will use the functions 354 * specified in lzma_allocator for memory handling instead of the default 355 * malloc() and free(). C++ users should note that the custom memory 356 * handling functions must not throw exceptions. 357 * 358 * Single-threaded mode only: liblzma doesn't make an internal copy of 359 * lzma_allocator. Thus, it is OK to change these function pointers in 360 * the middle of the coding process, but obviously it must be done 361 * carefully to make sure that the replacement `free' can deallocate 362 * memory allocated by the earlier `alloc' function(s). 363 * 364 * Multithreaded mode: liblzma might internally store pointers to the 365 * lzma_allocator given via the lzma_stream structure. The application 366 * must not change the allocator pointer in lzma_stream or the contents 367 * of the pointed lzma_allocator structure until lzma_end() has been used 368 * to free the memory associated with that lzma_stream. The allocation 369 * functions might be called simultaneously from multiple threads, and 370 * thus they must be thread safe. 371 */ 372 typedef struct { 373 /** 374 * \brief Pointer to a custom memory allocation function 375 * 376 * If you don't want a custom allocator, but still want 377 * custom free(), set this to NULL and liblzma will use 378 * the standard malloc(). 379 * 380 * \param opaque lzma_allocator.opaque (see below) 381 * \param nmemb Number of elements like in calloc(). liblzma 382 * will always set nmemb to 1, so it is safe to 383 * ignore nmemb in a custom allocator if you like. 384 * The nmemb argument exists only for 385 * compatibility with zlib and libbzip2. 386 * \param size Size of an element in bytes. 387 * liblzma never sets this to zero. 388 * 389 * \return Pointer to the beginning of a memory block of 390 * `size' bytes, or NULL if allocation fails 391 * for some reason. When allocation fails, functions 392 * of liblzma return LZMA_MEM_ERROR. 393 * 394 * The allocator should not waste time zeroing the allocated buffers. 395 * This is not only about speed, but also memory usage, since the 396 * operating system kernel doesn't necessarily allocate the requested 397 * memory in physical memory until it is actually used. With small 398 * input files, liblzma may actually need only a fraction of the 399 * memory that it requested for allocation. 400 * 401 * \note LZMA_MEM_ERROR is also used when the size of the 402 * allocation would be greater than SIZE_MAX. Thus, 403 * don't assume that the custom allocator must have 404 * returned NULL if some function from liblzma 405 * returns LZMA_MEM_ERROR. 406 */ 407 void *(LZMA_API_CALL *alloc)(void *opaque, size_t nmemb, size_t size); 408 409 /** 410 * \brief Pointer to a custom memory freeing function 411 * 412 * If you don't want a custom freeing function, but still 413 * want a custom allocator, set this to NULL and liblzma 414 * will use the standard free(). 415 * 416 * \param opaque lzma_allocator.opaque (see below) 417 * \param ptr Pointer returned by lzma_allocator.alloc(), 418 * or when it is set to NULL, a pointer returned 419 * by the standard malloc(). 420 */ 421 void (LZMA_API_CALL *free)(void *opaque, void *ptr); 422 423 /** 424 * \brief Pointer passed to .alloc() and .free() 425 * 426 * opaque is passed as the first argument to lzma_allocator.alloc() 427 * and lzma_allocator.free(). This intended to ease implementing 428 * custom memory allocation functions for use with liblzma. 429 * 430 * If you don't need this, you should set this to NULL. 431 */ 432 void *opaque; 433 434 } lzma_allocator; 435 436 437 /** 438 * \brief Internal data structure 439 * 440 * The contents of this structure is not visible outside the library. 441 */ 442 typedef struct lzma_internal_s lzma_internal; 443 444 445 /** 446 * \brief Passing data to and from liblzma 447 * 448 * The lzma_stream structure is used for 449 * - passing pointers to input and output buffers to liblzma; 450 * - defining custom memory hander functions; and 451 * - holding a pointer to coder-specific internal data structures. 452 * 453 * Typical usage: 454 * 455 * - After allocating lzma_stream (on stack or with malloc()), it must be 456 * initialized to LZMA_STREAM_INIT (see LZMA_STREAM_INIT for details). 457 * 458 * - Initialize a coder to the lzma_stream, for example by using 459 * lzma_easy_encoder() or lzma_auto_decoder(). Some notes: 460 * - In contrast to zlib, strm->next_in and strm->next_out are 461 * ignored by all initialization functions, thus it is safe 462 * to not initialize them yet. 463 * - The initialization functions always set strm->total_in and 464 * strm->total_out to zero. 465 * - If the initialization function fails, no memory is left allocated 466 * that would require freeing with lzma_end() even if some memory was 467 * associated with the lzma_stream structure when the initialization 468 * function was called. 469 * 470 * - Use lzma_code() to do the actual work. 471 * 472 * - Once the coding has been finished, the existing lzma_stream can be 473 * reused. It is OK to reuse lzma_stream with different initialization 474 * function without calling lzma_end() first. Old allocations are 475 * automatically freed. 476 * 477 * - Finally, use lzma_end() to free the allocated memory. lzma_end() never 478 * frees the lzma_stream structure itself. 479 * 480 * Application may modify the values of total_in and total_out as it wants. 481 * They are updated by liblzma to match the amount of data read and 482 * written but aren't used for anything else except as a possible return 483 * values from lzma_get_progress(). 484 */ 485 typedef struct { 486 const uint8_t *next_in; /**< Pointer to the next input byte. */ 487 size_t avail_in; /**< Number of available input bytes in next_in. */ 488 uint64_t total_in; /**< Total number of bytes read by liblzma. */ 489 490 uint8_t *next_out; /**< Pointer to the next output position. */ 491 size_t avail_out; /**< Amount of free space in next_out. */ 492 uint64_t total_out; /**< Total number of bytes written by liblzma. */ 493 494 /** 495 * \brief Custom memory allocation functions 496 * 497 * In most cases this is NULL which makes liblzma use 498 * the standard malloc() and free(). 499 * 500 * \note In 5.0.x this is not a const pointer. 501 */ 502 const lzma_allocator *allocator; 503 504 /** Internal state is not visible to applications. */ 505 lzma_internal *internal; 506 507 /* 508 * Reserved space to allow possible future extensions without 509 * breaking the ABI. Excluding the initialization of this structure, 510 * you should not touch these, because the names of these variables 511 * may change. 512 */ 513 void *reserved_ptr1; 514 void *reserved_ptr2; 515 void *reserved_ptr3; 516 void *reserved_ptr4; 517 uint64_t reserved_int1; 518 uint64_t reserved_int2; 519 size_t reserved_int3; 520 size_t reserved_int4; 521 lzma_reserved_enum reserved_enum1; 522 lzma_reserved_enum reserved_enum2; 523 524 } lzma_stream; 525 526 527 /** 528 * \brief Initialization for lzma_stream 529 * 530 * When you declare an instance of lzma_stream, you can immediately 531 * initialize it so that initialization functions know that no memory 532 * has been allocated yet: 533 * 534 * lzma_stream strm = LZMA_STREAM_INIT; 535 * 536 * If you need to initialize a dynamically allocated lzma_stream, you can use 537 * memset(strm_pointer, 0, sizeof(lzma_stream)). Strictly speaking, this 538 * violates the C standard since NULL may have different internal 539 * representation than zero, but it should be portable enough in practice. 540 * Anyway, for maximum portability, you can use something like this: 541 * 542 * lzma_stream tmp = LZMA_STREAM_INIT; 543 * *strm = tmp; 544 */ 545 #define LZMA_STREAM_INIT \ 546 { NULL, 0, 0, NULL, 0, 0, NULL, NULL, \ 547 NULL, NULL, NULL, NULL, 0, 0, 0, 0, \ 548 LZMA_RESERVED_ENUM, LZMA_RESERVED_ENUM } 549 550 551 /** 552 * \brief Encode or decode data 553 * 554 * Once the lzma_stream has been successfully initialized (e.g. with 555 * lzma_stream_encoder()), the actual encoding or decoding is done 556 * using this function. The application has to update strm->next_in, 557 * strm->avail_in, strm->next_out, and strm->avail_out to pass input 558 * to and get output from liblzma. 559 * 560 * See the description of the coder-specific initialization function to find 561 * out what `action' values are supported by the coder. 562 */ 563 extern LZMA_API(lzma_ret) lzma_code(lzma_stream *strm, lzma_action action) 564 lzma_nothrow lzma_attr_warn_unused_result; 565 566 567 /** 568 * \brief Free memory allocated for the coder data structures 569 * 570 * \param strm Pointer to lzma_stream that is at least initialized 571 * with LZMA_STREAM_INIT. 572 * 573 * After lzma_end(strm), strm->internal is guaranteed to be NULL. No other 574 * members of the lzma_stream structure are touched. 575 * 576 * \note zlib indicates an error if application end()s unfinished 577 * stream structure. liblzma doesn't do this, and assumes that 578 * application knows what it is doing. 579 */ 580 extern LZMA_API(void) lzma_end(lzma_stream *strm) lzma_nothrow; 581 582 583 /** 584 * \brief Get progress information 585 * 586 * In single-threaded mode, applications can get progress information from 587 * strm->total_in and strm->total_out. In multi-threaded mode this is less 588 * useful because a significant amount of both input and output data gets 589 * buffered internally by liblzma. This makes total_in and total_out give 590 * misleading information and also makes the progress indicator updates 591 * non-smooth. 592 * 593 * This function gives realistic progress information also in multi-threaded 594 * mode by taking into account the progress made by each thread. In 595 * single-threaded mode *progress_in and *progress_out are set to 596 * strm->total_in and strm->total_out, respectively. 597 */ 598 extern LZMA_API(void) lzma_get_progress(lzma_stream *strm, 599 uint64_t *progress_in, uint64_t *progress_out) lzma_nothrow; 600 601 602 /** 603 * \brief Get the memory usage of decoder filter chain 604 * 605 * This function is currently supported only when *strm has been initialized 606 * with a function that takes a memlimit argument. With other functions, you 607 * should use e.g. lzma_raw_encoder_memusage() or lzma_raw_decoder_memusage() 608 * to estimate the memory requirements. 609 * 610 * This function is useful e.g. after LZMA_MEMLIMIT_ERROR to find out how big 611 * the memory usage limit should have been to decode the input. Note that 612 * this may give misleading information if decoding .xz Streams that have 613 * multiple Blocks, because each Block can have different memory requirements. 614 * 615 * \return How much memory is currently allocated for the filter 616 * decoders. If no filter chain is currently allocated, 617 * some non-zero value is still returned, which is less than 618 * or equal to what any filter chain would indicate as its 619 * memory requirement. 620 * 621 * If this function isn't supported by *strm or some other error 622 * occurs, zero is returned. 623 */ 624 extern LZMA_API(uint64_t) lzma_memusage(const lzma_stream *strm) 625 lzma_nothrow lzma_attr_pure; 626 627 628 /** 629 * \brief Get the current memory usage limit 630 * 631 * This function is supported only when *strm has been initialized with 632 * a function that takes a memlimit argument. 633 * 634 * \return On success, the current memory usage limit is returned 635 * (always non-zero). On error, zero is returned. 636 */ 637 extern LZMA_API(uint64_t) lzma_memlimit_get(const lzma_stream *strm) 638 lzma_nothrow lzma_attr_pure; 639 640 641 /** 642 * \brief Set the memory usage limit 643 * 644 * This function is supported only when *strm has been initialized with 645 * a function that takes a memlimit argument. 646 * 647 * \return - LZMA_OK: New memory usage limit successfully set. 648 * - LZMA_MEMLIMIT_ERROR: The new limit is too small. 649 * The limit was not changed. 650 * - LZMA_PROG_ERROR: Invalid arguments, e.g. *strm doesn't 651 * support memory usage limit or memlimit was zero. 652 */ 653 extern LZMA_API(lzma_ret) lzma_memlimit_set( 654 lzma_stream *strm, uint64_t memlimit) lzma_nothrow; 655