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-rw-r--r--src/liblzma/api/lzma/container.h163
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