diff options
Diffstat (limited to 'src/liblzma/api')
| -rw-r--r-- | src/liblzma/api/lzma/container.h | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/src/liblzma/api/lzma/container.h b/src/liblzma/api/lzma/container.h index 48a64365..7e4ca3bf 100644 --- a/src/liblzma/api/lzma/container.h +++ b/src/liblzma/api/lzma/container.h @@ -436,6 +436,34 @@ extern LZMA_API(lzma_ret) lzma_stream_encoder_mt( /** + * \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 |