diff options
| author | Jia Tan <jiat0218@gmail.com> | 2023-05-09 20:20:06 +0800 |
|---|---|---|
| committer | Jia Tan <jiat0218@gmail.com> | 2023-05-11 23:54:44 +0800 |
| commit | 8f236574986e7c414c0ea059f441982d1387e6a4 (patch) | |
| tree | a7f93f05e0905183658a452528c9d4bb9a4ebd81 /src/liblzma/common/stream_encoder_mt.c | |
| parent | liblzma: Creates IS_ENC_DICT_SIZE_VALID() macro. (diff) | |
| download | xz-8f236574986e7c414c0ea059f441982d1387e6a4.tar.xz | |
liblzma: Exports lzma_mt_block_size() as an API function.
The lzma_mt_block_size() was previously just an internal function for
the multithreaded .xz encoder. It is used to provide a recommended Block
size for a given filter chain.
This function is helpful to determine the maximum Block size for the
multithreaded .xz encoder when one wants to change the filters between
blocks. Then, this determined Block size can be provided to
lzma_stream_encoder_mt() in the lzma_mt options parameter when
intializing the coder. This requires one to know all the filter chains
they are using before starting to encode (or at least the filter chain
that will need the largest Block size), but that isn't a bad limitation.
Diffstat (limited to '')
| -rw-r--r-- | src/liblzma/common/stream_encoder_mt.c | 20 |
1 files changed, 9 insertions, 11 deletions
diff --git a/src/liblzma/common/stream_encoder_mt.c b/src/liblzma/common/stream_encoder_mt.c index 5990742b..703b794e 100644 --- a/src/liblzma/common/stream_encoder_mt.c +++ b/src/liblzma/common/stream_encoder_mt.c @@ -979,20 +979,18 @@ get_options(const lzma_mt *options, lzma_options_easy *opt_easy, *filters = opt_easy->filters; } - // Block size - if (options->block_size > 0) { - if (options->block_size > BLOCK_SIZE_MAX) - return LZMA_OPTIONS_ERROR; - + // If the Block size is not set, determine it from the filter chain. + if (options->block_size > 0) *block_size = options->block_size; - } else { - // Determine the Block size from the filter chain. + else *block_size = lzma_mt_block_size(*filters); - if (*block_size == 0) - return LZMA_OPTIONS_ERROR; - assert(*block_size <= BLOCK_SIZE_MAX); - } + // UINT64_MAX > BLOCK_SIZE_MAX, so the second condition + // should be optimized out by any reasonable compiler. + // The second condition should be there in the unlikely event that + // the macros change and UINT64_MAX < BLOCK_SIZE_MAX. + if (*block_size > BLOCK_SIZE_MAX || *block_size == UINT64_MAX) + return LZMA_OPTIONS_ERROR; // Calculate the maximum amount output that a single output buffer // may need to hold. This is the same as the maximum total size of |