diff options
Diffstat (limited to 'src/liblzma/api')
| -rw-r--r-- | src/liblzma/api/lzma/container.h | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/src/liblzma/api/lzma/container.h b/src/liblzma/api/lzma/container.h index 7a9ffc64..e68c8940 100644 --- a/src/liblzma/api/lzma/container.h +++ b/src/liblzma/api/lzma/container.h @@ -61,6 +61,127 @@ /** + * \brief Multithreading options + */ +typedef struct { + /** + * \brief Flags + * + * Set this to zero if no flags are wanted. + * + * No flags are currently supported. + */ + uint32_t flags; + + /** + * \brief Number of worker threads to use + */ + uint32_t threads; + + /** + * \brief 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. + */ + uint64_t block_size; + + /** + * \brief Timeout to allow lzma_code() to return early + * + * Multithreading can make liblzma to 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 fine for you, set timeout to a special + * value of 0, which 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 + * somewhat long time to return. No timing guarantees + * are made. + */ + uint32_t timeout; + + /** + * \brief Compression preset (level and possible flags) + * + * The preset is set just like with lzma_easy_encoder(). + * The preset is ignored if filters below is non-NULL. + */ + uint32_t preset; + + /** + * \brief 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 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. + */ + lzma_reserved_enum reserved_enum1; + lzma_reserved_enum reserved_enum2; + lzma_reserved_enum reserved_enum3; + uint32_t reserved_int1; + uint32_t reserved_int2; + uint32_t reserved_int3; + uint32_t reserved_int4; + uint64_t reserved_int5; + uint64_t reserved_int6; + uint64_t reserved_int7; + uint64_t reserved_int8; + void *reserved_ptr1; + void *reserved_ptr2; + void *reserved_ptr3; + void *reserved_ptr4; + +} lzma_mt; + + +/** * \brief Calculate approximate memory usage of easy encoder * * This function is a wrapper for lzma_raw_encoder_memusage(). @@ -191,6 +312,48 @@ extern LZMA_API(lzma_ret) lzma_stream_encoder(lzma_stream *strm, /** + * \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. + * + * TODO: For lzma_code(), only LZMA_RUN and LZMA_FINISH are currently + * supported. Support for other actions has been planned. + * + * \param strm Pointer to properly prepared lzma_stream + * \param options Pointer to multithreaded compression options + * + * \return - 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 |