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xz/src/liblzma/api/lzma/container.h

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/* SPDX-License-Identifier: 0BSD */
/**
* \file lzma/container.h
* \brief File formats
* \note Never include this file directly. Use <lzma.h> instead.
*/
/*
* Author: Lasse Collin
*/
#ifndef LZMA_H_INTERNAL
# error Never include this file directly. Use <lzma.h> 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 Calculate recommended Block size for multithreaded .xz encoder
*
* This calculates a recommended Block size for multithreaded encoding given
* a filter chain. This is used internally by lzma_stream_encoder_mt() to
* determine the Block size if the block_size member is not set to the
* special value of 0 in the lzma_mt options struct.
*
* If one wishes to change the filters between Blocks, this function is
* helpful to set the block_size member of the lzma_mt struct before calling
* lzma_stream_encoder_mt(). Since the block_size member represents the
* maximum possible Block size for the multithreaded .xz encoder, one can
* use this function to find the maximum recommended Block size based on
* all planned filter chains. Otherwise, the multithreaded encoder will
* base its maximum Block size on the first filter chain used (if the
* block_size member is not set), which may unnecessarily limit the Block
* size for a later filter chain.
*
* \param filters Array of filters terminated with
* .id == LZMA_VLI_UNKNOWN.
*
* \return Recommended Block size in bytes, or UINT64_MAX if
* an error occurred.
*/
extern LZMA_API(uint64_t) lzma_mt_block_size(const lzma_filter *filters)
lzma_nothrow;
/**
* \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;
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