diff options
Diffstat (limited to '')
| -rw-r--r-- | src/liblzma/api/lzma/container.h | 90 |
1 files changed, 83 insertions, 7 deletions
diff --git a/src/liblzma/api/lzma/container.h b/src/liblzma/api/lzma/container.h index cbb37c8b..b2b912d5 100644 --- a/src/liblzma/api/lzma/container.h +++ b/src/liblzma/api/lzma/container.h @@ -69,7 +69,11 @@ typedef struct { * * Set this to zero if no flags are wanted. * - * No flags are currently supported. + * 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_CONCATENATED */ uint32_t flags; @@ -79,7 +83,7 @@ typedef struct { uint32_t threads; /** - * \brief Maximum uncompressed size of a Block + * \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() @@ -135,7 +139,7 @@ typedef struct { uint32_t timeout; /** - * \brief Compression preset (level and possible flags) + * \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. @@ -143,7 +147,7 @@ typedef struct { uint32_t preset; /** - * \brief Filter chain (alternative to a 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. @@ -151,7 +155,7 @@ typedef struct { const lzma_filter *filters; /** - * \brief Integrity check type + * \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 @@ -173,8 +177,50 @@ typedef struct { uint32_t reserved_int2; uint32_t reserved_int3; uint32_t reserved_int4; - uint64_t reserved_int5; - uint64_t reserved_int6; + + /** + * \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; + uint64_t reserved_int7; uint64_t reserved_int8; void *reserved_ptr1; @@ -593,6 +639,36 @@ extern LZMA_API(lzma_ret) lzma_stream_decoder( /** + * \brief Initialize multithreaded .xz Stream decoder + * + * \param strm Pointer to properly prepared lzma_stream + * \param options Pointer to multithreaded compression options + * + * 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. + * + * \return - 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 Streams and .lzma files with autodetection * * This decoder autodetects between the .xz and .lzma file formats, and |