/** * \file lzma/container.h * \brief File formats * \note Never include this file directly. Use instead. */ /* * Author: Lasse Collin * * This file has been put into the public domain. * You can do whatever you want with this file. */ #ifndef LZMA_H_INTERNAL # error Never include this file directly. Use instead. #endif /************ * Encoding * ************/ /** * \brief Default compression preset * * It's not straightforward to recommend a default preset, because in some * cases keeping the resource usage relatively low is more important that * getting the maximum compression ratio. */ #define LZMA_PRESET_DEFAULT UINT32_C(6) /** * \brief Mask for preset level * * This is useful only if you need to extract the level from the preset * variable. That should be rare. */ #define LZMA_PRESET_LEVEL_MASK UINT32_C(0x1F) /* * Preset flags * * Currently only one flag is defined. */ /** * \brief Extreme compression preset * * This flag modifies the preset to make the encoding significantly slower * while improving the compression ratio only marginally. This is useful * when you don't mind spending time to get as small result as possible. * * This flag doesn't affect the memory usage requirements of the decoder (at * least not significantly). The memory usage of the encoder may be increased * a little but only at the lowest preset levels (0-3). */ #define LZMA_PRESET_EXTREME (UINT32_C(1) << 31) /** * \brief Multithreading options */ typedef struct { /** * \brief Flags * * Set this to zero if no flags are wanted. * * Encoder: No flags are currently supported. * * Decoder: Bitwise-or of zero or more of the decoder flags: * - LZMA_TELL_NO_CHECK * - LZMA_TELL_UNSUPPORTED_CHECK * - LZMA_TELL_ANY_CHECK * - LZMA_IGNORE_CHECK * - LZMA_CONCATENATED * - LZMA_FAIL_FAST */ uint32_t flags; /** * \brief Number of worker threads to use */ uint32_t threads; /** * \brief Encoder only: Maximum uncompressed size of a Block * * The encoder will start a new .xz Block every block_size bytes. * Using LZMA_FULL_FLUSH or LZMA_FULL_BARRIER with lzma_code() * the caller may tell liblzma to start a new Block earlier. * * With LZMA2, a recommended block size is 2-4 times the LZMA2 * dictionary size. With very small dictionaries, it is recommended * to use at least 1 MiB block size for good compression ratio, even * if this is more than four times the dictionary size. Note that * these are only recommendations for typical use cases; feel free * to use other values. Just keep in mind that using a block size * less than the LZMA2 dictionary size is waste of RAM. * * Set this to 0 to let liblzma choose the block size depending * on the compression options. For LZMA2 it will be 3*dict_size * or 1 MiB, whichever is more. * * For each thread, about 3 * block_size bytes of memory will be * allocated. This may change in later liblzma versions. If so, * the memory usage will probably be reduced, not increased. */ uint64_t block_size; /** * \brief Timeout to allow lzma_code() to return early * * Multithreading can make liblzma consume input and produce * output in a very bursty way: it may first read a lot of input * to fill internal buffers, then no input or output occurs for * a while. * * In single-threaded mode, lzma_code() won't return until it has * either consumed all the input or filled the output buffer. If * this is done in multithreaded mode, it may cause a call * lzma_code() to take even tens of seconds, which isn't acceptable * in all applications. * * To avoid very long blocking times in lzma_code(), a timeout * (in milliseconds) may be set here. If lzma_code() would block * longer than this number of milliseconds, it will return with * LZMA_OK. Reasonable values are 100 ms or more. The xz command * line tool uses 300 ms. * * If long blocking times are acceptable, set timeout to a special * value of 0. This will disable the timeout mechanism and will make * lzma_code() block until all the input is consumed or the output * buffer has been filled. * * \note Even with a timeout, lzma_code() might sometimes take * a long time to return. No timing guarantees are made. */ uint32_t timeout; /** * \brief Encoder only: Compression preset * * The preset is set just like with lzma_easy_encoder(). * The preset is ignored if filters below is non-NULL. */ uint32_t preset; /** * \brief Encoder only: Filter chain (alternative to a preset) * * If this is NULL, the preset above is used. Otherwise the preset * is ignored and the filter chain specified here is used. */ const lzma_filter *filters; /** * \brief Encoder only: Integrity check type * * See check.h for available checks. The xz command line tool * defaults to LZMA_CHECK_CRC64, which is a good choice if you * are unsure. */ lzma_check check; /* * 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. */ /** \private Reserved member. */ lzma_reserved_enum reserved_enum1; /** \private Reserved member. */ lzma_reserved_enum reserved_enum2; /** \private Reserved member. */ lzma_reserved_enum reserved_enum3; /** \private Reserved member. */ uint32_t reserved_int1; /** \private Reserved member. */ uint32_t reserved_int2; /** \private Reserved member. */ uint32_t reserved_int3; /** \private Reserved member. */ uint32_t reserved_int4; /** * \brief Memory usage limit to reduce the number of threads * * Encoder: Ignored. * * Decoder: * * If the number of threads has been set so high that more than * memlimit_threading bytes of memory would be needed, the number * of threads will be reduced so that the memory usage will not exceed * memlimit_threading bytes. However, if memlimit_threading cannot * be met even in single-threaded mode, then decoding will continue * in single-threaded mode and memlimit_threading may be exceeded * even by a large amount. That is, memlimit_threading will never make * lzma_code() return LZMA_MEMLIMIT_ERROR. To truly cap the memory * usage, see memlimit_stop below. * * Setting memlimit_threading to UINT64_MAX or a similar huge value * means that liblzma is allowed to keep the whole compressed file * and the whole uncompressed file in memory in addition to the memory * needed by the decompressor data structures used by each thread! * In other words, a reasonable value limit must be set here or it * will cause problems sooner or later. If you have no idea what * a reasonable value could be, try lzma_physmem() / 4 as a starting * point. Setting this limit will never prevent decompression of * a file; this will only reduce the number of threads. * * If memlimit_threading is greater than memlimit_stop, then the value * of memlimit_stop will be used for both. */ uint64_t memlimit_threading; /** * \brief Memory usage limit that should never be exceeded * * Encoder: Ignored. * * Decoder: If decompressing will need more than this amount of * memory even in the single-threaded mode, then lzma_code() will * return LZMA_MEMLIMIT_ERROR. */ uint64_t memlimit_stop; /** \private Reserved member. */ uint64_t reserved_int7; /** \private Reserved member. */ uint64_t reserved_int8; /** \private Reserved member. */ void *reserved_ptr1; /** \private Reserved member. */ void *reserved_ptr2; /** \private Reserved member. */ void *reserved_ptr3; /** \private Reserved member. */ void *reserved_ptr4; } lzma_mt; /** * \brief Calculate approximate memory usage of easy encoder * * This function is a wrapper for lzma_raw_encoder_memusage(). * * \param preset Compression preset (level and possible flags) * * \return Number of bytes of memory required for the given * preset when encoding or UINT64_MAX on error. */ extern LZMA_API(uint64_t) lzma_easy_encoder_memusage(uint32_t preset) lzma_nothrow lzma_attr_pure; /** * \brief Calculate approximate decoder memory usage of a preset * * This function is a wrapper for lzma_raw_decoder_memusage(). * * \param preset Compression preset (level and possible flags) * * \return Number of bytes of memory required to decompress a file * that was compressed using the given preset or UINT64_MAX * on error. */ extern LZMA_API(uint64_t) lzma_easy_decoder_memusage(uint32_t preset) lzma_nothrow lzma_attr_pure; /** * \brief Initialize .xz Stream encoder using a preset number * * This function is intended for those who just want to use the basic features * of liblzma (that is, most developers out there). * * If initialization fails (return value is not LZMA_OK), all the memory * allocated for *strm by liblzma is always freed. Thus, there is no need * to call lzma_end() after failed initialization. * * If initialization succeeds, use lzma_code() to do the actual encoding. * Valid values for `action' (the second argument of lzma_code()) are * LZMA_RUN, LZMA_SYNC_FLUSH, LZMA_FULL_FLUSH, and LZMA_FINISH. In future, * there may be compression levels or flags that don't support LZMA_SYNC_FLUSH. * * \param strm Pointer to lzma_stream that is at least initialized * with LZMA_STREAM_INIT. * \param preset Compression preset to use. A preset consist of level * number and zero or more flags. Usually flags aren't * used, so preset is simply a number [0, 9] which match * the options -0 ... -9 of the xz command line tool. * Additional flags can be be set using bitwise-or with * the preset level number, e.g. 6 | LZMA_PRESET_EXTREME. * \param check Integrity check type to use. See check.h for available * checks. The xz command line tool defaults to * LZMA_CHECK_CRC64, which is a good choice if you are * unsure. LZMA_CHECK_CRC32 is good too as long as the * uncompressed file is not many gigabytes. * * \return Possible lzma_ret values: * - LZMA_OK: Initialization succeeded. Use lzma_code() to * encode your data. * - LZMA_MEM_ERROR: Memory allocation failed. * - LZMA_OPTIONS_ERROR: The given compression preset is not * supported by this build of liblzma. * - LZMA_UNSUPPORTED_CHECK: The given check type is not * supported by this liblzma build. * - LZMA_PROG_ERROR: One or more of the parameters have values * that will never be valid. For example, strm == NULL. */ extern LZMA_API(lzma_ret) lzma_easy_encoder( lzma_stream *strm, uint32_t preset, lzma_check check) lzma_nothrow lzma_attr_warn_unused_result; /** * \brief Single-call .xz Stream encoding using a preset number * * The maximum required output buffer size can be calculated with * lzma_stream_buffer_bound(). * * \param preset Compression preset to use. See the description * in lzma_easy_encoder(). * \param check Type of the integrity check to calculate from * uncompressed data. * \param allocator lzma_allocator for custom allocator functions. * Set to NULL to use malloc() and free(). * \param in Beginning of the input buffer * \param in_size Size of the input buffer * \param[out] out Beginning of the output buffer * \param[out] out_pos The next byte will be written to out[*out_pos]. * *out_pos is updated only if encoding succeeds. * \param out_size Size of the out buffer; the first byte into * which no data is written to is out[out_size]. * * \return Possible lzma_ret values: * - LZMA_OK: Encoding was successful. * - LZMA_BUF_ERROR: Not enough output buffer space. * - LZMA_UNSUPPORTED_CHECK * - LZMA_OPTIONS_ERROR * - LZMA_MEM_ERROR * - LZMA_DATA_ERROR * - LZMA_PROG_ERROR */ extern LZMA_API(lzma_ret) lzma_easy_buffer_encode( uint32_t preset, lzma_check check, const lzma_allocator *allocator, const uint8_t *in, size_t in_size, uint8_t *out, size_t *out_pos, size_t out_size) lzma_nothrow; /** * \brief Initialize .xz Stream encoder using a custom filter chain * * \param strm Pointer to lzma_stream that is at least initialized * with LZMA_STREAM_INIT. * \param filters Array of filters terminated with * .id == LZMA_VLI_UNKNOWN. See filters.h for more * information. * \param check Type of the integrity check to calculate from * uncompressed data. * * \return Possible lzma_ret values: * - LZMA_OK: Initialization was successful. * - LZMA_MEM_ERROR * - LZMA_UNSUPPORTED_CHECK * - LZMA_OPTIONS_ERROR * - LZMA_PROG_ERROR */ extern LZMA_API(lzma_ret) lzma_stream_encoder(lzma_stream *strm, const lzma_filter *filters, lzma_check check) lzma_nothrow lzma_attr_warn_unused_result; /** * \brief Calculate approximate memory usage of multithreaded .xz encoder * * Since doing the encoding in threaded mode doesn't affect the memory * requirements of single-threaded decompressor, you can use * lzma_easy_decoder_memusage(options->preset) or * lzma_raw_decoder_memusage(options->filters) to calculate * the decompressor memory requirements. * * \param options Compression options * * \return Number of bytes of memory required for encoding with the * given options. If an error occurs, for example due to * unsupported preset or filter chain, UINT64_MAX is returned. */ extern LZMA_API(uint64_t) lzma_stream_encoder_mt_memusage( const lzma_mt *options) lzma_nothrow lzma_attr_pure; /** * \brief Initialize multithreaded .xz Stream encoder * * This provides the functionality of lzma_easy_encoder() and * lzma_stream_encoder() as a single function for multithreaded use. * * The supported actions for lzma_code() are LZMA_RUN, LZMA_FULL_FLUSH, * LZMA_FULL_BARRIER, and LZMA_FINISH. Support for LZMA_SYNC_FLUSH might be * added in the future. * * \param strm Pointer to lzma_stream that is at least initialized * with LZMA_STREAM_INIT. * \param options Pointer to multithreaded compression options * * \return Possible lzma_ret values: * - LZMA_OK * - LZMA_MEM_ERROR * - LZMA_UNSUPPORTED_CHECK * - LZMA_OPTIONS_ERROR * - LZMA_PROG_ERROR */ extern LZMA_API(lzma_ret) lzma_stream_encoder_mt( lzma_stream *strm, const lzma_mt *options) lzma_nothrow lzma_attr_warn_unused_result; /** * \brief Initialize .lzma encoder (legacy file format) * * The .lzma format is sometimes called the LZMA_Alone format, which is the * reason for the name of this function. The .lzma format supports only the * LZMA1 filter. There is no support for integrity checks like CRC32. * * Use this function if and only if you need to create files readable by * legacy LZMA tools such as LZMA Utils 4.32.x. Moving to the .xz format * is strongly recommended. * * The valid action values for lzma_code() are LZMA_RUN and LZMA_FINISH. * No kind of flushing is supported, because the file format doesn't make * it possible. * * \param strm Pointer to lzma_stream that is at least initialized * with LZMA_STREAM_INIT. * \param options Pointer to encoder options * * \return Possible lzma_ret values: * - LZMA_OK * - LZMA_MEM_ERROR * - LZMA_OPTIONS_ERROR * - LZMA_PROG_ERROR */ extern LZMA_API(lzma_ret) lzma_alone_encoder( lzma_stream *strm, const lzma_options_lzma *options) lzma_nothrow lzma_attr_warn_unused_result; /** * \brief Calculate output buffer size for single-call Stream encoder * * When trying to compress incompressible data, the encoded size will be * slightly bigger than the input data. This function calculates how much * output buffer space is required to be sure that lzma_stream_buffer_encode() * doesn't return LZMA_BUF_ERROR. * * The calculated value is not exact, but it is guaranteed to be big enough. * The actual maximum output space required may be slightly smaller (up to * about 100 bytes). This should not be a problem in practice. * * If the calculated maximum size doesn't fit into size_t or would make the * Stream grow past LZMA_VLI_MAX (which should never happen in practice), * zero is returned to indicate the error. * * \note The limit calculated by this function applies only to * single-call encoding. Multi-call encoding may (and probably * will) have larger maximum expansion when encoding * incompressible data. Currently there is no function to * calculate the maximum expansion of multi-call encoding. * * \param uncompressed_size Size in bytes of the uncompressed * input data * * \return Maximum number of bytes needed to store the compressed data. */ extern LZMA_API(size_t) lzma_stream_buffer_bound(size_t uncompressed_size) lzma_nothrow; /** * \brief Single-call .xz Stream encoder * * \param filters Array of filters terminated with * .id == LZMA_VLI_UNKNOWN. See filters.h for more * information. * \param check Type of the integrity check to calculate from * uncompressed data. * \param allocator lzma_allocator for custom allocator functions. * Set to NULL to use malloc() and free(). * \param in Beginning of the input buffer * \param in_size Size of the input buffer * \param[out] out Beginning of the output buffer * \param[out] out_pos The next byte will be written to out[*out_pos]. * *out_pos is updated only if encoding succeeds. * \param out_size Size of the out buffer; the first byte into * which no data is written to is out[out_size]. * * \return Possible lzma_ret values: * - LZMA_OK: Encoding was successful. * - LZMA_BUF_ERROR: Not enough output buffer space. * - LZMA_UNSUPPORTED_CHECK * - LZMA_OPTIONS_ERROR * - LZMA_MEM_ERROR * - LZMA_DATA_ERROR * - LZMA_PROG_ERROR */ extern LZMA_API(lzma_ret) lzma_stream_buffer_encode( lzma_filter *filters, lzma_check check, const lzma_allocator *allocator, const uint8_t *in, size_t in_size, uint8_t *out, size_t *out_pos, size_t out_size) lzma_nothrow lzma_attr_warn_unused_result; /** * \brief MicroLZMA encoder * * The MicroLZMA format is a raw LZMA stream whose first byte (always 0x00) * has been replaced with bitwise-negation of the LZMA properties (lc/lp/pb). * This encoding ensures that the first byte of MicroLZMA stream is never * 0x00. There is no end of payload marker and thus the uncompressed size * must be stored separately. For the best error detection the dictionary * size should be stored separately as well but alternatively one may use * the uncompressed size as the dictionary size when decoding. * * With the MicroLZMA encoder, lzma_code() behaves slightly unusually. * The action argument must be LZMA_FINISH and the return value will never be * LZMA_OK. Thus the encoding is always done with a single lzma_code() after * the initialization. The benefit of the combination of initialization * function and lzma_code() is that memory allocations can be re-used for * better performance. * * lzma_code() will try to encode as much input as is possible to fit into * the given output buffer. If not all input can be encoded, the stream will * be finished without encoding all the input. The caller must check both * input and output buffer usage after lzma_code() (total_in and total_out * in lzma_stream can be convenient). Often lzma_code() can fill the output * buffer completely if there is a lot of input, but sometimes a few bytes * may remain unused because the next LZMA symbol would require more space. * * lzma_stream.avail_out must be at least 6. Otherwise LZMA_PROG_ERROR * will be returned. * * The LZMA dictionary should be reasonably low to speed up the encoder * re-initialization. A good value is bigger than the resulting * uncompressed size of most of the output chunks. For example, if output * size is 4 KiB, dictionary size of 32 KiB or 64 KiB is good. If the * data compresses extremely well, even 128 KiB may be useful. * * The MicroLZMA format and this encoder variant were made with the EROFS * file system in mind. This format may be convenient in other embedded * uses too where many small streams are needed. XZ Embedded includes a * decoder for this format. * * \param strm Pointer to lzma_stream that is at least initialized * with LZMA_STREAM_INIT. * \param options Pointer to encoder options * * \return Possible lzma_ret values: * - LZMA_STREAM_END: All good. Check the amounts of input used * and output produced. Store the amount of input used * (uncompressed size) as it needs to be known to decompress * the data. * - LZMA_OPTIONS_ERROR * - LZMA_MEM_ERROR * - LZMA_PROG_ERROR: In addition to the generic reasons for this * error code, this may also be returned if there isn't enough * output space (6 bytes) to create a valid MicroLZMA stream. */ extern LZMA_API(lzma_ret) lzma_microlzma_encoder( lzma_stream *strm, const lzma_options_lzma *options) lzma_nothrow; /************ * Decoding * ************/ /** * This flag makes lzma_code() return LZMA_NO_CHECK if the input stream * being decoded has no integrity check. Note that when used with * lzma_auto_decoder(), all .lzma files will trigger LZMA_NO_CHECK * if LZMA_TELL_NO_CHECK is used. */ #define LZMA_TELL_NO_CHECK UINT32_C(0x01) /** * This flag makes lzma_code() return LZMA_UNSUPPORTED_CHECK if the input * stream has an integrity check, but the type of the integrity check is not * supported by this liblzma version or build. Such files can still be * decoded, but the integrity check cannot be verified. */ #define LZMA_TELL_UNSUPPORTED_CHECK UINT32_C(0x02) /** * This flag makes lzma_code() return LZMA_GET_CHECK as soon as the type * of the integrity check is known. The type can then be got with * lzma_get_check(). */ #define LZMA_TELL_ANY_CHECK UINT32_C(0x04) /** * This flag makes lzma_code() not calculate and verify the integrity check * of the compressed data in .xz files. This means that invalid integrity * check values won't be detected and LZMA_DATA_ERROR won't be returned in * such cases. * * This flag only affects the checks of the compressed data itself; the CRC32 * values in the .xz headers will still be verified normally. * * Don't use this flag unless you know what you are doing. Possible reasons * to use this flag: * * - Trying to recover data from a corrupt .xz file. * * - Speeding up decompression, which matters mostly with SHA-256 * or with files that have compressed extremely well. It's recommended * to not use this flag for this purpose unless the file integrity is * verified externally in some other way. * * Support for this flag was added in liblzma 5.1.4beta. */ #define LZMA_IGNORE_CHECK UINT32_C(0x10) /** * This flag enables decoding of concatenated files with file formats that * allow concatenating compressed files as is. From the formats currently * supported by liblzma, only the .xz and .lz formats allow concatenated * files. Concatenated files are not allowed with the legacy .lzma format. * * This flag also affects the usage of the `action' argument for lzma_code(). * When LZMA_CONCATENATED is used, lzma_code() won't return LZMA_STREAM_END * unless LZMA_FINISH is used as `action'. Thus, the application has to set * LZMA_FINISH in the same way as it does when encoding. * * If LZMA_CONCATENATED is not used, the decoders still accept LZMA_FINISH * as `action' for lzma_code(), but the usage of LZMA_FINISH isn't required. */ #define LZMA_CONCATENATED UINT32_C(0x08) /** * This flag makes the threaded decoder report errors (like LZMA_DATA_ERROR) * as soon as they are detected. This saves time when the application has no * interest in a partially decompressed truncated or corrupt file. Note that * due to timing randomness, if the same truncated or corrupt input is * decompressed multiple times with this flag, a different amount of output * may be produced by different runs, and even the error code might vary. * * When using LZMA_FAIL_FAST, it is recommended to use LZMA_FINISH to tell * the decoder when no more input will be coming because it can help fast * detection and reporting of truncated files. Note that in this situation * truncated files might be diagnosed with LZMA_DATA_ERROR instead of * LZMA_OK or LZMA_BUF_ERROR! * * Without this flag the threaded decoder will provide as much output as * possible at first and then report the pending error. This default behavior * matches the single-threaded decoder and provides repeatable behavior * with truncated or corrupt input. There are a few special cases where the * behavior can still differ like memory allocation failures (LZMA_MEM_ERROR). * * Single-threaded decoders currently ignore this flag. * * Support for this flag was added in liblzma 5.3.3alpha. Note that in older * versions this flag isn't supported (LZMA_OPTIONS_ERROR) even by functions * that ignore this flag in newer liblzma versions. */ #define LZMA_FAIL_FAST UINT32_C(0x20) /** * \brief Initialize .xz Stream decoder * * \param strm Pointer to lzma_stream that is at least initialized * with LZMA_STREAM_INIT. * \param memlimit Memory usage limit as bytes. Use UINT64_MAX * to effectively disable the limiter. liblzma * 5.2.3 and earlier don't allow 0 here and return * LZMA_PROG_ERROR; later versions treat 0 as if 1 * had been specified. * \param flags Bitwise-or of zero or more of the decoder flags: * LZMA_TELL_NO_CHECK, LZMA_TELL_UNSUPPORTED_CHECK, * LZMA_TELL_ANY_CHECK, LZMA_IGNORE_CHECK, * LZMA_CONCATENATED, LZMA_FAIL_FAST * * \return Possible lzma_ret values: * - LZMA_OK: Initialization was successful. * - LZMA_MEM_ERROR: Cannot allocate memory. * - LZMA_OPTIONS_ERROR: Unsupported flags * - LZMA_PROG_ERROR */ extern LZMA_API(lzma_ret) lzma_stream_decoder( lzma_stream *strm, uint64_t memlimit, uint32_t flags) lzma_nothrow lzma_attr_warn_unused_result; /** * \brief Initialize multithreaded .xz Stream decoder * * The decoder can decode multiple Blocks in parallel. This requires that each * Block Header contains the Compressed Size and Uncompressed size fields * which are added by the multi-threaded encoder, see lzma_stream_encoder_mt(). * * A Stream with one Block will only utilize one thread. A Stream with multiple * Blocks but without size information in Block Headers will be processed in * single-threaded mode in the same way as done by lzma_stream_decoder(). * Concatenated Streams are processed one Stream at a time; no inter-Stream * parallelization is done. * * This function behaves like lzma_stream_decoder() when options->threads == 1 * and options->memlimit_threading <= 1. * * \param strm Pointer to lzma_stream that is at least initialized * with LZMA_STREAM_INIT. * \param options Pointer to multithreaded compression options * * \return Possible lzma_ret values: * - LZMA_OK: Initialization was successful. * - LZMA_MEM_ERROR: Cannot allocate memory. * - LZMA_MEMLIMIT_ERROR: Memory usage limit was reached. * - LZMA_OPTIONS_ERROR: Unsupported flags. * - LZMA_PROG_ERROR */ extern LZMA_API(lzma_ret) lzma_stream_decoder_mt( lzma_stream *strm, const lzma_mt *options) lzma_nothrow lzma_attr_warn_unused_result; /** * \brief Decode .xz, .lzma, and .lz (lzip) files with autodetection * * This decoder autodetects between the .xz, .lzma, and .lz file formats, * and calls lzma_stream_decoder(), lzma_alone_decoder(), or * lzma_lzip_decoder() once the type of the input file has been detected. * * Support for .lz was added in 5.4.0. * * If the flag LZMA_CONCATENATED is used and the input is a .lzma file: * For historical reasons concatenated .lzma files aren't supported. * If there is trailing data after one .lzma stream, lzma_code() will * return LZMA_DATA_ERROR. (lzma_alone_decoder() doesn't have such a check * as it doesn't support any decoder flags. It will return LZMA_STREAM_END * after one .lzma stream.) * * \param strm Pointer to lzma_stream that is at least initialized * with LZMA_STREAM_INIT. * \param memlimit Memory usage limit as bytes. Use UINT64_MAX * to effectively disable the limiter. liblzma * 5.2.3 and earlier don't allow 0 here and return * LZMA_PROG_ERROR; later versions treat 0 as if 1 * had been specified. * \param flags Bitwise-or of zero or more of the decoder flags: * LZMA_TELL_NO_CHECK, LZMA_TELL_UNSUPPORTED_CHECK, * LZMA_TELL_ANY_CHECK, LZMA_IGNORE_CHECK, * LZMA_CONCATENATED, LZMA_FAIL_FAST * * \return Possible lzma_ret values: * - LZMA_OK: Initialization was successful. * - LZMA_MEM_ERROR: Cannot allocate memory. * - LZMA_OPTIONS_ERROR: Unsupported flags * - LZMA_PROG_ERROR */ extern LZMA_API(lzma_ret) lzma_auto_decoder( lzma_stream *strm, uint64_t memlimit, uint32_t flags) lzma_nothrow lzma_attr_warn_unused_result; /** * \brief Initialize .lzma decoder (legacy file format) * * Valid `action' arguments to lzma_code() are LZMA_RUN and LZMA_FINISH. * There is no need to use LZMA_FINISH, but it's allowed because it may * simplify certain types of applications. * * \param strm Pointer to lzma_stream that is at least initialized * with LZMA_STREAM_INIT. * \param memlimit Memory usage limit as bytes. Use UINT64_MAX * to effectively disable the limiter. liblzma * 5.2.3 and earlier don't allow 0 here and return * LZMA_PROG_ERROR; later versions treat 0 as if 1 * had been specified. * * \return Possible lzma_ret values: * - LZMA_OK * - LZMA_MEM_ERROR * - LZMA_PROG_ERROR */ extern LZMA_API(lzma_ret) lzma_alone_decoder( lzma_stream *strm, uint64_t memlimit) lzma_nothrow lzma_attr_warn_unused_result; /** * \brief Initialize .lz (lzip) decoder (a foreign file format) * * This decoder supports the .lz format version 0 and the unextended .lz * format version 1: * * - Files in the format version 0 were produced by lzip 1.3 and older. * Such files aren't common but may be found from file archives * as a few source packages were released in this format. People * might have old personal files in this format too. Decompression * support for the format version 0 was removed in lzip 1.18. * * - lzip 1.3 added decompression support for .lz format version 1 files. * Compression support was added in lzip 1.4. In lzip 1.6 the .lz format * version 1 was extended to support the Sync Flush marker. This extension * is not supported by liblzma. lzma_code() will return LZMA_DATA_ERROR * at the location of the Sync Flush marker. In practice files with * the Sync Flush marker are very rare and thus liblzma can decompress * almost all .lz files. * * Just like with lzma_stream_decoder() for .xz files, LZMA_CONCATENATED * should be used when decompressing normal standalone .lz files. * * The .lz format allows putting non-.lz data at the end of a file after at * least one valid .lz member. That is, one can append custom data at the end * of a .lz file and the decoder is required to ignore it. In liblzma this * is relevant only when LZMA_CONCATENATED is used. In that case lzma_code() * will return LZMA_STREAM_END and leave lzma_stream.next_in pointing to * the first byte of the non-.lz data. An exception to this is if the first * 1-3 bytes of the non-.lz data are identical to the .lz magic bytes * (0x4C, 0x5A, 0x49, 0x50; "LZIP" in US-ASCII). In such a case the 1-3 bytes * will have been ignored by lzma_code(). If one wishes to locate the non-.lz * data reliably, one must ensure that the first byte isn't 0x4C. Actually * one should ensure that none of the first four bytes of trailing data are * equal to the magic bytes because lzip >= 1.20 requires it by default. * * \param strm Pointer to lzma_stream that is at least initialized * with LZMA_STREAM_INIT. * \param memlimit Memory usage limit as bytes. Use UINT64_MAX * to effectively disable the limiter. * \param flags Bitwise-or of flags, or zero for no flags. * All decoder flags listed above are supported * although only LZMA_CONCATENATED and (in very rare * cases) LZMA_IGNORE_CHECK are actually useful. * LZMA_TELL_NO_CHECK, LZMA_TELL_UNSUPPORTED_CHECK, * and LZMA_FAIL_FAST do nothing. LZMA_TELL_ANY_CHECK * is supported for consistency only as CRC32 is * always used in the .lz format. * * \return Possible lzma_ret values: * - LZMA_OK: Initialization was successful. * - LZMA_MEM_ERROR: Cannot allocate memory. * - LZMA_OPTIONS_ERROR: Unsupported flags * - LZMA_PROG_ERROR */ extern LZMA_API(lzma_ret) lzma_lzip_decoder( lzma_stream *strm, uint64_t memlimit, uint32_t flags) lzma_nothrow lzma_attr_warn_unused_result; /** * \brief Single-call .xz Stream decoder * * \param memlimit Pointer to how much memory the decoder is allowed * to allocate. The value pointed by this pointer is * modified if and only if LZMA_MEMLIMIT_ERROR is * returned. * \param flags Bitwise-or of zero or more of the decoder flags: * LZMA_TELL_NO_CHECK, LZMA_TELL_UNSUPPORTED_CHECK, * LZMA_IGNORE_CHECK, LZMA_CONCATENATED, * LZMA_FAIL_FAST. Note that LZMA_TELL_ANY_CHECK * is not allowed and will return LZMA_PROG_ERROR. * \param allocator lzma_allocator for custom allocator functions. * Set to NULL to use malloc() and free(). * \param in Beginning of the input buffer * \param in_pos The next byte will be read from in[*in_pos]. * *in_pos is updated only if decoding succeeds. * \param in_size Size of the input buffer; the first byte that * won't be read is in[in_size]. * \param[out] out Beginning of the output buffer * \param[out] out_pos The next byte will be written to out[*out_pos]. * *out_pos is updated only if decoding succeeds. * \param out_size Size of the out buffer; the first byte into * which no data is written to is out[out_size]. * * \return Possible lzma_ret values: * - LZMA_OK: Decoding was successful. * - LZMA_FORMAT_ERROR * - LZMA_OPTIONS_ERROR * - LZMA_DATA_ERROR * - LZMA_NO_CHECK: This can be returned only if using * the LZMA_TELL_NO_CHECK flag. * - LZMA_UNSUPPORTED_CHECK: This can be returned only if using * the LZMA_TELL_UNSUPPORTED_CHECK flag. * - LZMA_MEM_ERROR * - LZMA_MEMLIMIT_ERROR: Memory usage limit was reached. * The minimum required memlimit value was stored to *memlimit. * - LZMA_BUF_ERROR: Output buffer was too small. * - LZMA_PROG_ERROR */ extern LZMA_API(lzma_ret) lzma_stream_buffer_decode( uint64_t *memlimit, uint32_t flags, const lzma_allocator *allocator, const uint8_t *in, size_t *in_pos, size_t in_size, uint8_t *out, size_t *out_pos, size_t out_size) lzma_nothrow lzma_attr_warn_unused_result; /** * \brief MicroLZMA decoder * * See lzma_microlzma_encoder() for more information. * * The lzma_code() usage with this decoder is completely normal. The * special behavior of lzma_code() applies to lzma_microlzma_encoder() only. * * \param strm Pointer to lzma_stream that is at least initialized * with LZMA_STREAM_INIT. * \param comp_size Compressed size of the MicroLZMA stream. * The caller must somehow know this exactly. * \param uncomp_size Uncompressed size of the MicroLZMA stream. * If the exact uncompressed size isn't known, this * can be set to a value that is at most as big as * the exact uncompressed size would be, but then the * next argument uncomp_size_is_exact must be false. * \param uncomp_size_is_exact * If true, uncomp_size must be exactly correct. * This will improve error detection at the end of * the stream. If the exact uncompressed size isn't * known, this must be false. uncomp_size must still * be at most as big as the exact uncompressed size * is. Setting this to false when the exact size is * known will work but error detection at the end of * the stream will be weaker. * \param dict_size LZMA dictionary size that was used when * compressing the data. It is OK to use a bigger * value too but liblzma will then allocate more * memory than would actually be required and error * detection will be slightly worse. (Note that with * the implementation in XZ Embedded it doesn't * affect the memory usage if one specifies bigger * dictionary than actually required.) * * \return Possible lzma_ret values: * - LZMA_OK * - LZMA_MEM_ERROR * - LZMA_OPTIONS_ERROR * - LZMA_PROG_ERROR */ extern LZMA_API(lzma_ret) lzma_microlzma_decoder( lzma_stream *strm, uint64_t comp_size, uint64_t uncomp_size, lzma_bool uncomp_size_is_exact, uint32_t dict_size) lzma_nothrow;