--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/include/lzma/index.h	Tue Mar 18 17:55:14 2025 -0400
@@ -0,0 +1,882 @@
+/* SPDX-License-Identifier: 0BSD */
+
+/**
+ * \file        lzma/index.h
+ * \brief       Handling of .xz Index and related information
+ * \note        Never include this file directly. Use <lzma.h> instead.
+ */
+
+/*
+ * Author: Lasse Collin
+ */
+
+#ifndef LZMA_H_INTERNAL
+#	error Never include this file directly. Use <lzma.h> instead.
+#endif
+
+
+/**
+ * \brief       Opaque data type to hold the Index(es) and other information
+ *
+ * lzma_index often holds just one .xz Index and possibly the Stream Flags
+ * of the same Stream and size of the Stream Padding field. However,
+ * multiple lzma_indexes can be concatenated with lzma_index_cat() and then
+ * there may be information about multiple Streams in the same lzma_index.
+ *
+ * Notes about thread safety: Only one thread may modify lzma_index at
+ * a time. All functions that take non-const pointer to lzma_index
+ * modify it. As long as no thread is modifying the lzma_index, getting
+ * information from the same lzma_index can be done from multiple threads
+ * at the same time with functions that take a const pointer to
+ * lzma_index or use lzma_index_iter. The same iterator must be used
+ * only by one thread at a time, of course, but there can be as many
+ * iterators for the same lzma_index as needed.
+ */
+typedef struct lzma_index_s lzma_index;
+
+
+/**
+ * \brief       Iterator to get information about Blocks and Streams
+ */
+typedef struct {
+	struct {
+		/**
+		 * \brief       Pointer to Stream Flags
+		 *
+		 * This is NULL if Stream Flags have not been set for
+		 * this Stream with lzma_index_stream_flags().
+		 */
+		const lzma_stream_flags *flags;
+
+		/** \private     Reserved member. */
+		const void *reserved_ptr1;
+
+		/** \private     Reserved member. */
+		const void *reserved_ptr2;
+
+		/** \private     Reserved member. */
+		const void *reserved_ptr3;
+
+		/**
+		 * \brief       Stream number in the lzma_index
+		 *
+		 * The first Stream is 1.
+		 */
+		lzma_vli number;
+
+		/**
+		 * \brief       Number of Blocks in the Stream
+		 *
+		 * If this is zero, the block structure below has
+		 * undefined values.
+		 */
+		lzma_vli block_count;
+
+		/**
+		 * \brief       Compressed start offset of this Stream
+		 *
+		 * The offset is relative to the beginning of the lzma_index
+		 * (i.e. usually the beginning of the .xz file).
+		 */
+		lzma_vli compressed_offset;
+
+		/**
+		 * \brief       Uncompressed start offset of this Stream
+		 *
+		 * The offset is relative to the beginning of the lzma_index
+		 * (i.e. usually the beginning of the .xz file).
+		 */
+		lzma_vli uncompressed_offset;
+
+		/**
+		 * \brief       Compressed size of this Stream
+		 *
+		 * This includes all headers except the possible
+		 * Stream Padding after this Stream.
+		 */
+		lzma_vli compressed_size;
+
+		/**
+		 * \brief       Uncompressed size of this Stream
+		 */
+		lzma_vli uncompressed_size;
+
+		/**
+		 * \brief       Size of Stream Padding after this Stream
+		 *
+		 * If it hasn't been set with lzma_index_stream_padding(),
+		 * this defaults to zero. Stream Padding is always
+		 * a multiple of four bytes.
+		 */
+		lzma_vli padding;
+
+
+		/** \private     Reserved member. */
+		lzma_vli reserved_vli1;
+
+		/** \private     Reserved member. */
+		lzma_vli reserved_vli2;
+
+		/** \private     Reserved member. */
+		lzma_vli reserved_vli3;
+
+		/** \private     Reserved member. */
+		lzma_vli reserved_vli4;
+	} stream;
+
+	struct {
+		/**
+		 * \brief       Block number in the file
+		 *
+		 * The first Block is 1.
+		 */
+		lzma_vli number_in_file;
+
+		/**
+		 * \brief       Compressed start offset of this Block
+		 *
+		 * This offset is relative to the beginning of the
+		 * lzma_index (i.e. usually the beginning of the .xz file).
+		 * Normally this is where you should seek in the .xz file
+		 * to start decompressing this Block.
+		 */
+		lzma_vli compressed_file_offset;
+
+		/**
+		 * \brief       Uncompressed start offset of this Block
+		 *
+		 * This offset is relative to the beginning of the lzma_index
+		 * (i.e. usually the beginning of the .xz file).
+		 *
+		 * When doing random-access reading, it is possible that
+		 * the target offset is not exactly at Block boundary. One
+		 * will need to compare the target offset against
+		 * uncompressed_file_offset or uncompressed_stream_offset,
+		 * and possibly decode and throw away some amount of data
+		 * before reaching the target offset.
+		 */
+		lzma_vli uncompressed_file_offset;
+
+		/**
+		 * \brief       Block number in this Stream
+		 *
+		 * The first Block is 1.
+		 */
+		lzma_vli number_in_stream;
+
+		/**
+		 * \brief       Compressed start offset of this Block
+		 *
+		 * This offset is relative to the beginning of the Stream
+		 * containing this Block.
+		 */
+		lzma_vli compressed_stream_offset;
+
+		/**
+		 * \brief       Uncompressed start offset of this Block
+		 *
+		 * This offset is relative to the beginning of the Stream
+		 * containing this Block.
+		 */
+		lzma_vli uncompressed_stream_offset;
+
+		/**
+		 * \brief       Uncompressed size of this Block
+		 *
+		 * You should pass this to the Block decoder if you will
+		 * decode this Block. It will allow the Block decoder to
+		 * validate the uncompressed size.
+		 */
+		lzma_vli uncompressed_size;
+
+		/**
+		 * \brief       Unpadded size of this Block
+		 *
+		 * You should pass this to the Block decoder if you will
+		 * decode this Block. It will allow the Block decoder to
+		 * validate the unpadded size.
+		 */
+		lzma_vli unpadded_size;
+
+		/**
+		 * \brief       Total compressed size
+		 *
+		 * This includes all headers and padding in this Block.
+		 * This is useful if you need to know how many bytes
+		 * the Block decoder will actually read.
+		 */
+		lzma_vli total_size;
+
+		/** \private     Reserved member. */
+		lzma_vli reserved_vli1;
+
+		/** \private     Reserved member. */
+		lzma_vli reserved_vli2;
+
+		/** \private     Reserved member. */
+		lzma_vli reserved_vli3;
+
+		/** \private     Reserved member. */
+		lzma_vli reserved_vli4;
+
+		/** \private     Reserved member. */
+		const void *reserved_ptr1;
+
+		/** \private     Reserved member. */
+		const void *reserved_ptr2;
+
+		/** \private     Reserved member. */
+		const void *reserved_ptr3;
+
+		/** \private     Reserved member. */
+		const void *reserved_ptr4;
+	} block;
+
+	/**
+	 * \private     Internal data
+	 *
+	 * Internal data which is used to store the state of the iterator.
+	 * The exact format may vary between liblzma versions, so don't
+	 * touch these in any way.
+	 */
+	union {
+		/** \private     Internal member. */
+		const void *p;
+
+		/** \private     Internal member. */
+		size_t s;
+
+		/** \private     Internal member. */
+		lzma_vli v;
+	} internal[6];
+} lzma_index_iter;
+
+
+/**
+ * \brief       Operation mode for lzma_index_iter_next()
+ */
+typedef enum {
+	LZMA_INDEX_ITER_ANY             = 0,
+		/**<
+		 * \brief       Get the next Block or Stream
+		 *
+		 * Go to the next Block if the current Stream has at least
+		 * one Block left. Otherwise go to the next Stream even if
+		 * it has no Blocks. If the Stream has no Blocks
+		 * (lzma_index_iter.stream.block_count == 0),
+		 * lzma_index_iter.block will have undefined values.
+		 */
+
+	LZMA_INDEX_ITER_STREAM          = 1,
+		/**<
+		 * \brief       Get the next Stream
+		 *
+		 * Go to the next Stream even if the current Stream has
+		 * unread Blocks left. If the next Stream has at least one
+		 * Block, the iterator will point to the first Block.
+		 * If there are no Blocks, lzma_index_iter.block will have
+		 * undefined values.
+		 */
+
+	LZMA_INDEX_ITER_BLOCK           = 2,
+		/**<
+		 * \brief       Get the next Block
+		 *
+		 * Go to the next Block if the current Stream has at least
+		 * one Block left. If the current Stream has no Blocks left,
+		 * the next Stream with at least one Block is located and
+		 * the iterator will be made to point to the first Block of
+		 * that Stream.
+		 */
+
+	LZMA_INDEX_ITER_NONEMPTY_BLOCK  = 3
+		/**<
+		 * \brief       Get the next non-empty Block
+		 *
+		 * This is like LZMA_INDEX_ITER_BLOCK except that it will
+		 * skip Blocks whose Uncompressed Size is zero.
+		 */
+
+} lzma_index_iter_mode;
+
+
+/**
+ * \brief       Mask for return value from lzma_index_checks() for check none
+ *
+ * \note        This and the other CHECK_MASK macros were added in 5.5.1alpha.
+ */
+#define LZMA_INDEX_CHECK_MASK_NONE (UINT32_C(1) << LZMA_CHECK_NONE)
+
+/**
+ * \brief       Mask for return value from lzma_index_checks() for check CRC32
+ */
+#define LZMA_INDEX_CHECK_MASK_CRC32 (UINT32_C(1) << LZMA_CHECK_CRC32)
+
+/**
+ * \brief       Mask for return value from lzma_index_checks() for check CRC64
+ */
+#define LZMA_INDEX_CHECK_MASK_CRC64 (UINT32_C(1) << LZMA_CHECK_CRC64)
+
+/**
+ * \brief       Mask for return value from lzma_index_checks() for check SHA256
+ */
+#define LZMA_INDEX_CHECK_MASK_SHA256 (UINT32_C(1) << LZMA_CHECK_SHA256)
+
+/**
+ * \brief       Calculate memory usage of lzma_index
+ *
+ * On disk, the size of the Index field depends on both the number of Records
+ * stored and the size of the Records (due to variable-length integer
+ * encoding). When the Index is kept in lzma_index structure, the memory usage
+ * depends only on the number of Records/Blocks stored in the Index(es), and
+ * in case of concatenated lzma_indexes, the number of Streams. The size in
+ * RAM is almost always significantly bigger than in the encoded form on disk.
+ *
+ * This function calculates an approximate amount of memory needed to hold
+ * the given number of Streams and Blocks in lzma_index structure. This
+ * value may vary between CPU architectures and also between liblzma versions
+ * if the internal implementation is modified.
+ *
+ * \param       streams Number of Streams
+ * \param       blocks  Number of Blocks
+ *
+ * \return      Approximate memory in bytes needed in a lzma_index structure.
+ */
+extern LZMA_API(uint64_t) lzma_index_memusage(
+		lzma_vli streams, lzma_vli blocks) lzma_nothrow;
+
+
+/**
+ * \brief       Calculate the memory usage of an existing lzma_index
+ *
+ * This is a shorthand for lzma_index_memusage(lzma_index_stream_count(i),
+ * lzma_index_block_count(i)).
+ *
+ * \param       i   Pointer to lzma_index structure
+ *
+ * \return      Approximate memory in bytes used by the lzma_index structure.
+ */
+extern LZMA_API(uint64_t) lzma_index_memused(const lzma_index *i)
+		lzma_nothrow;
+
+
+/**
+ * \brief       Allocate and initialize a new lzma_index structure
+ *
+ * \param       allocator   lzma_allocator for custom allocator functions.
+ *                          Set to NULL to use malloc() and free().
+ *
+ * \return      On success, a pointer to an empty initialized lzma_index is
+ *              returned. If allocation fails, NULL is returned.
+ */
+extern LZMA_API(lzma_index *) lzma_index_init(const lzma_allocator *allocator)
+		lzma_nothrow;
+
+
+/**
+ * \brief       Deallocate lzma_index
+ *
+ * If i is NULL, this does nothing.
+ *
+ * \param       i           Pointer to lzma_index structure to deallocate
+ * \param       allocator   lzma_allocator for custom allocator functions.
+ *                          Set to NULL to use malloc() and free().
+ */
+extern LZMA_API(void) lzma_index_end(
+		lzma_index *i, const lzma_allocator *allocator) lzma_nothrow;
+
+
+/**
+ * \brief       Add a new Block to lzma_index
+ *
+ * \param       i                 Pointer to a lzma_index structure
+ * \param       allocator         lzma_allocator for custom allocator
+ *                                functions. Set to NULL to use malloc()
+ *                                and free().
+ * \param       unpadded_size     Unpadded Size of a Block. This can be
+ *                                calculated with lzma_block_unpadded_size()
+ *                                after encoding or decoding the Block.
+ * \param       uncompressed_size Uncompressed Size of a Block. This can be
+ *                                taken directly from lzma_block structure
+ *                                after encoding or decoding the Block.
+ *
+ * Appending a new Block does not invalidate iterators. For example,
+ * if an iterator was pointing to the end of the lzma_index, after
+ * lzma_index_append() it is possible to read the next Block with
+ * an existing iterator.
+ *
+ * \return      Possible lzma_ret values:
+ *              - LZMA_OK
+ *              - LZMA_MEM_ERROR
+ *              - LZMA_DATA_ERROR: Compressed or uncompressed size of the
+ *                Stream or size of the Index field would grow too big.
+ *              - LZMA_PROG_ERROR
+ */
+extern LZMA_API(lzma_ret) lzma_index_append(
+		lzma_index *i, const lzma_allocator *allocator,
+		lzma_vli unpadded_size, lzma_vli uncompressed_size)
+		lzma_nothrow lzma_attr_warn_unused_result;
+
+
+/**
+ * \brief       Set the Stream Flags
+ *
+ * Set the Stream Flags of the last (and typically the only) Stream
+ * in lzma_index. This can be useful when reading information from the
+ * lzma_index, because to decode Blocks, knowing the integrity check type
+ * is needed.
+ *
+ * \param       i              Pointer to lzma_index structure
+ * \param       stream_flags   Pointer to lzma_stream_flags structure. This
+ *                             is copied into the internal preallocated
+ *                             structure, so the caller doesn't need to keep
+ *                             the flags' data available after calling this
+ *                             function.
+ *
+ * \return      Possible lzma_ret values:
+ *              - LZMA_OK
+ *              - LZMA_OPTIONS_ERROR: Unsupported stream_flags->version.
+ *              - LZMA_PROG_ERROR
+ */
+extern LZMA_API(lzma_ret) lzma_index_stream_flags(
+		lzma_index *i, const lzma_stream_flags *stream_flags)
+		lzma_nothrow lzma_attr_warn_unused_result;
+
+
+/**
+ * \brief       Get the types of integrity Checks
+ *
+ * If lzma_index_stream_flags() is used to set the Stream Flags for
+ * every Stream, lzma_index_checks() can be used to get a bitmask to
+ * indicate which Check types have been used. It can be useful e.g. if
+ * showing the Check types to the user.
+ *
+ * The bitmask is 1 << check_id, e.g. CRC32 is 1 << 1 and SHA-256 is 1 << 10.
+ * These masks are defined for convenience as LZMA_INDEX_CHECK_MASK_XXX
+ *
+ * \param       i   Pointer to lzma_index structure
+ *
+ * \return      Bitmask indicating which Check types are used in the lzma_index
+ */
+extern LZMA_API(uint32_t) lzma_index_checks(const lzma_index *i)
+		lzma_nothrow lzma_attr_pure;
+
+
+/**
+ * \brief       Set the amount of Stream Padding
+ *
+ * Set the amount of Stream Padding of the last (and typically the only)
+ * Stream in the lzma_index. This is needed when planning to do random-access
+ * reading within multiple concatenated Streams.
+ *
+ * By default, the amount of Stream Padding is assumed to be zero bytes.
+ *
+ * \return      Possible lzma_ret values:
+ *              - LZMA_OK
+ *              - LZMA_DATA_ERROR: The file size would grow too big.
+ *              - LZMA_PROG_ERROR
+ */
+extern LZMA_API(lzma_ret) lzma_index_stream_padding(
+		lzma_index *i, lzma_vli stream_padding)
+		lzma_nothrow lzma_attr_warn_unused_result;
+
+
+/**
+ * \brief       Get the number of Streams
+ *
+ * \param       i   Pointer to lzma_index structure
+ *
+ * \return      Number of Streams in the lzma_index
+ */
+extern LZMA_API(lzma_vli) lzma_index_stream_count(const lzma_index *i)
+		lzma_nothrow lzma_attr_pure;
+
+
+/**
+ * \brief       Get the number of Blocks
+ *
+ * This returns the total number of Blocks in lzma_index. To get number
+ * of Blocks in individual Streams, use lzma_index_iter.
+ *
+ * \param       i   Pointer to lzma_index structure
+ *
+ * \return      Number of blocks in the lzma_index
+ */
+extern LZMA_API(lzma_vli) lzma_index_block_count(const lzma_index *i)
+		lzma_nothrow lzma_attr_pure;
+
+
+/**
+ * \brief       Get the size of the Index field as bytes
+ *
+ * This is needed to verify the Backward Size field in the Stream Footer.
+ *
+ * \param       i   Pointer to lzma_index structure
+ *
+ * \return      Size in bytes of the Index
+ */
+extern LZMA_API(lzma_vli) lzma_index_size(const lzma_index *i)
+		lzma_nothrow lzma_attr_pure;
+
+
+/**
+ * \brief       Get the total size of the Stream
+ *
+ * If multiple lzma_indexes have been combined, this works as if the Blocks
+ * were in a single Stream. This is useful if you are going to combine
+ * Blocks from multiple Streams into a single new Stream.
+ *
+ * \param       i   Pointer to lzma_index structure
+ *
+ * \return      Size in bytes of the Stream (if all Blocks are combined
+ *              into one Stream).
+ */
+extern LZMA_API(lzma_vli) lzma_index_stream_size(const lzma_index *i)
+		lzma_nothrow lzma_attr_pure;
+
+
+/**
+ * \brief       Get the total size of the Blocks
+ *
+ * This doesn't include the Stream Header, Stream Footer, Stream Padding,
+ * or Index fields.
+ *
+ * \param       i   Pointer to lzma_index structure
+ *
+ * \return      Size in bytes of all Blocks in the Stream(s)
+ */
+extern LZMA_API(lzma_vli) lzma_index_total_size(const lzma_index *i)
+		lzma_nothrow lzma_attr_pure;
+
+
+/**
+ * \brief       Get the total size of the file
+ *
+ * When no lzma_indexes have been combined with lzma_index_cat() and there is
+ * no Stream Padding, this function is identical to lzma_index_stream_size().
+ * If multiple lzma_indexes have been combined, this includes also the headers
+ * of each separate Stream and the possible Stream Padding fields.
+ *
+ * \param       i   Pointer to lzma_index structure
+ *
+ * \return      Total size of the .xz file in bytes
+ */
+extern LZMA_API(lzma_vli) lzma_index_file_size(const lzma_index *i)
+		lzma_nothrow lzma_attr_pure;
+
+
+/**
+ * \brief       Get the uncompressed size of the file
+ *
+ * \param       i   Pointer to lzma_index structure
+ *
+ * \return      Size in bytes of the uncompressed data in the file
+ */
+extern LZMA_API(lzma_vli) lzma_index_uncompressed_size(const lzma_index *i)
+		lzma_nothrow lzma_attr_pure;
+
+
+/**
+ * \brief       Initialize an iterator
+ *
+ * This function associates the iterator with the given lzma_index, and calls
+ * lzma_index_iter_rewind() on the iterator.
+ *
+ * This function doesn't allocate any memory, thus there is no
+ * lzma_index_iter_end(). The iterator is valid as long as the
+ * associated lzma_index is valid, that is, until lzma_index_end() or
+ * using it as source in lzma_index_cat(). Specifically, lzma_index doesn't
+ * become invalid if new Blocks are added to it with lzma_index_append() or
+ * if it is used as the destination in lzma_index_cat().
+ *
+ * It is safe to make copies of an initialized lzma_index_iter, for example,
+ * to easily restart reading at some particular position.
+ *
+ * \param       iter    Pointer to a lzma_index_iter structure
+ * \param       i       lzma_index to which the iterator will be associated
+ */
+extern LZMA_API(void) lzma_index_iter_init(
+		lzma_index_iter *iter, const lzma_index *i) lzma_nothrow;
+
+
+/**
+ * \brief       Rewind the iterator
+ *
+ * Rewind the iterator so that next call to lzma_index_iter_next() will
+ * return the first Block or Stream.
+ *
+ * \param       iter    Pointer to a lzma_index_iter structure
+ */
+extern LZMA_API(void) lzma_index_iter_rewind(lzma_index_iter *iter)
+		lzma_nothrow;
+
+
+/**
+ * \brief       Get the next Block or Stream
+ *
+ * \param       iter    Iterator initialized with lzma_index_iter_init()
+ * \param       mode    Specify what kind of information the caller wants
+ *                      to get. See lzma_index_iter_mode for details.
+ *
+ * \return      lzma_bool:
+ *              - true if no Block or Stream matching the mode is found.
+ *                *iter is not updated (failure).
+ *              - false if the next Block or Stream matching the mode was
+ *                found. *iter is updated (success).
+ */
+extern LZMA_API(lzma_bool) lzma_index_iter_next(
+		lzma_index_iter *iter, lzma_index_iter_mode mode)
+		lzma_nothrow lzma_attr_warn_unused_result;
+
+
+/**
+ * \brief       Locate a Block
+ *
+ * If it is possible to seek in the .xz file, it is possible to parse
+ * the Index field(s) and use lzma_index_iter_locate() to do random-access
+ * reading with granularity of Block size.
+ *
+ * If the target is smaller than the uncompressed size of the Stream (can be
+ * checked with lzma_index_uncompressed_size()):
+ *  - Information about the Stream and Block containing the requested
+ *    uncompressed offset is stored into *iter.
+ *  - Internal state of the iterator is adjusted so that
+ *    lzma_index_iter_next() can be used to read subsequent Blocks or Streams.
+ *
+ * If the target is greater than the uncompressed size of the Stream, *iter
+ * is not modified.
+ *
+ * \param       iter    Iterator that was earlier initialized with
+ *                      lzma_index_iter_init().
+ * \param       target  Uncompressed target offset which the caller would
+ *                      like to locate from the Stream
+ *
+ * \return      lzma_bool:
+ *              - true if the target is greater than or equal to the
+ *                uncompressed size of the Stream (failure)
+ *              - false if the target is smaller than the uncompressed size
+ *                of the Stream (success)
+ */
+extern LZMA_API(lzma_bool) lzma_index_iter_locate(
+		lzma_index_iter *iter, lzma_vli target) lzma_nothrow;
+
+
+/**
+ * \brief       Concatenate lzma_indexes
+ *
+ * Concatenating lzma_indexes is useful when doing random-access reading in
+ * multi-Stream .xz file, or when combining multiple Streams into single
+ * Stream.
+ *
+ * \param[out]  dest      lzma_index after which src is appended
+ * \param       src       lzma_index to be appended after dest. If this
+ *                        function succeeds, the memory allocated for src
+ *                        is freed or moved to be part of dest, and all
+ *                        iterators pointing to src will become invalid.
+ * \param       allocator lzma_allocator for custom allocator functions.
+ *                        Set to NULL to use malloc() and free().
+ *
+ * \return      Possible lzma_ret values:
+ *              - LZMA_OK: lzma_indexes were concatenated successfully.
+ *                src is now a dangling pointer.
+ *              - LZMA_DATA_ERROR: *dest would grow too big.
+ *              - LZMA_MEM_ERROR
+ *              - LZMA_PROG_ERROR
+ */
+extern LZMA_API(lzma_ret) lzma_index_cat(lzma_index *dest, lzma_index *src,
+		const lzma_allocator *allocator)
+		lzma_nothrow lzma_attr_warn_unused_result;
+
+
+/**
+ * \brief       Duplicate lzma_index
+ *
+ * \param       i         Pointer to lzma_index structure to be duplicated
+ * \param       allocator lzma_allocator for custom allocator functions.
+ *                        Set to NULL to use malloc() and free().
+ *
+ * \return      A copy of the lzma_index, or NULL if memory allocation failed.
+ */
+extern LZMA_API(lzma_index *) lzma_index_dup(
+		const lzma_index *i, const lzma_allocator *allocator)
+		lzma_nothrow lzma_attr_warn_unused_result;
+
+
+/**
+ * \brief       Initialize .xz Index encoder
+ *
+ * \param       strm        Pointer to properly prepared lzma_stream
+ * \param       i           Pointer to lzma_index which should be encoded.
+ *
+ * The valid 'action' values for lzma_code() are LZMA_RUN and LZMA_FINISH.
+ * It is enough to use only one of them (you can choose freely).
+ *
+ * \return      Possible lzma_ret values:
+ *              - LZMA_OK: Initialization succeeded, continue with lzma_code().
+ *              - LZMA_MEM_ERROR
+ *              - LZMA_PROG_ERROR
+ */
+extern LZMA_API(lzma_ret) lzma_index_encoder(
+		lzma_stream *strm, const lzma_index *i)
+		lzma_nothrow lzma_attr_warn_unused_result;
+
+
+/**
+ * \brief       Initialize .xz Index decoder
+ *
+ * \param       strm        Pointer to properly prepared lzma_stream
+ * \param[out]  i           The decoded Index will be made available via
+ *                          this pointer. Initially this function will
+ *                          set *i to NULL (the old value is ignored). If
+ *                          decoding succeeds (lzma_code() returns
+ *                          LZMA_STREAM_END), *i will be set to point
+ *                          to a new lzma_index, which the application
+ *                          has to later free with lzma_index_end().
+ * \param       memlimit    How much memory the resulting lzma_index is
+ *                          allowed to require. liblzma 5.2.3 and earlier
+ *                          don't allow 0 here and return LZMA_PROG_ERROR;
+ *                          later versions treat 0 as if 1 had been specified.
+ *
+ * Valid 'action' arguments to lzma_code() are LZMA_RUN and LZMA_FINISH.
+ * There is no need to use LZMA_FINISH, but it's allowed because it may
+ * simplify certain types of applications.
+ *
+ * \return      Possible lzma_ret values:
+ *              - LZMA_OK: Initialization succeeded, continue with lzma_code().
+ *              - LZMA_MEM_ERROR
+ *              - LZMA_PROG_ERROR
+ *
+ * \note        liblzma 5.2.3 and older list also LZMA_MEMLIMIT_ERROR here
+ *              but that error code has never been possible from this
+ *              initialization function.
+ */
+extern LZMA_API(lzma_ret) lzma_index_decoder(
+		lzma_stream *strm, lzma_index **i, uint64_t memlimit)
+		lzma_nothrow lzma_attr_warn_unused_result;
+
+
+/**
+ * \brief       Single-call .xz Index encoder
+ *
+ * \note        This function doesn't take allocator argument since all
+ *              the internal data is allocated on stack.
+ *
+ * \param       i         lzma_index to be encoded
+ * \param[out]  out       Beginning of the output buffer
+ * \param[out]  out_pos   The next byte will be written to out[*out_pos].
+ *                        *out_pos is updated only if encoding succeeds.
+ * \param       out_size  Size of the out buffer; the first byte into
+ *                        which no data is written to is out[out_size].
+ *
+ * \return      Possible lzma_ret values:
+ *              - LZMA_OK: Encoding was successful.
+ *              - LZMA_BUF_ERROR: Output buffer is too small. Use
+ *                lzma_index_size() to find out how much output
+ *                space is needed.
+ *              - LZMA_PROG_ERROR
+ *
+ */
+extern LZMA_API(lzma_ret) lzma_index_buffer_encode(const lzma_index *i,
+		uint8_t *out, size_t *out_pos, size_t out_size) lzma_nothrow;
+
+
+/**
+ * \brief       Single-call .xz Index decoder
+ *
+ * \param[out]  i           If decoding succeeds, *i will point to a new
+ *                          lzma_index, which the application has to
+ *                          later free with lzma_index_end(). If an error
+ *                          occurs, *i will be NULL. The old value of *i
+ *                          is always ignored and thus doesn't need to be
+ *                          initialized by the caller.
+ * \param[out]  memlimit    Pointer to how much memory the resulting
+ *                          lzma_index is allowed to require. The value
+ *                          pointed by this pointer is modified if and only
+ *                          if LZMA_MEMLIMIT_ERROR is returned.
+ * \param       allocator   lzma_allocator for custom allocator functions.
+ *                          Set to NULL to use malloc() and free().
+ * \param       in          Beginning of the input buffer
+ * \param       in_pos      The next byte will be read from in[*in_pos].
+ *                          *in_pos is updated only if decoding succeeds.
+ * \param       in_size     Size of the input buffer; the first byte that
+ *                          won't be read is in[in_size].
+ *
+ * \return      Possible lzma_ret values:
+ *              - LZMA_OK: Decoding was successful.
+ *              - LZMA_MEM_ERROR
+ *              - LZMA_MEMLIMIT_ERROR: Memory usage limit was reached.
+ *                The minimum required memlimit value was stored to *memlimit.
+ *              - LZMA_DATA_ERROR
+ *              - LZMA_PROG_ERROR
+ */
+extern LZMA_API(lzma_ret) lzma_index_buffer_decode(lzma_index **i,
+		uint64_t *memlimit, const lzma_allocator *allocator,
+		const uint8_t *in, size_t *in_pos, size_t in_size)
+		lzma_nothrow;
+
+
+/**
+ * \brief       Initialize a .xz file information decoder
+ *
+ * This decoder decodes the Stream Header, Stream Footer, Index, and
+ * Stream Padding field(s) from the input .xz file and stores the resulting
+ * combined index in *dest_index. This information can be used to get the
+ * uncompressed file size with lzma_index_uncompressed_size(*dest_index) or,
+ * for example, to implement random access reading by locating the Blocks
+ * in the Streams.
+ *
+ * To get the required information from the .xz file, lzma_code() may ask
+ * the application to seek in the input file by returning LZMA_SEEK_NEEDED
+ * and having the target file position specified in lzma_stream.seek_pos.
+ * The number of seeks required depends on the input file and how big buffers
+ * the application provides. When possible, the decoder will seek backward
+ * and forward in the given buffer to avoid useless seek requests. Thus, if
+ * the application provides the whole file at once, no external seeking will
+ * be required (that is, lzma_code() won't return LZMA_SEEK_NEEDED).
+ *
+ * The value in lzma_stream.total_in can be used to estimate how much data
+ * liblzma had to read to get the file information. However, due to seeking
+ * and the way total_in is updated, the value of total_in will be somewhat
+ * inaccurate (a little too big). Thus, total_in is a good estimate but don't
+ * expect to see the same exact value for the same file if you change the
+ * input buffer size or switch to a different liblzma version.
+ *
+ * Valid 'action' arguments to lzma_code() are LZMA_RUN and LZMA_FINISH.
+ * You only need to use LZMA_RUN; LZMA_FINISH is only supported because it
+ * might be convenient for some applications. If you use LZMA_FINISH and if
+ * lzma_code() asks the application to seek, remember to reset 'action' back
+ * to LZMA_RUN unless you hit the end of the file again.
+ *
+ * Possible return values from lzma_code():
+ *   - LZMA_OK: All OK so far, more input needed
+ *   - LZMA_SEEK_NEEDED: Provide more input starting from the absolute
+ *     file position strm->seek_pos
+ *   - LZMA_STREAM_END: Decoding was successful, *dest_index has been set
+ *   - LZMA_FORMAT_ERROR: The input file is not in the .xz format (the
+ *     expected magic bytes were not found from the beginning of the file)
+ *   - LZMA_OPTIONS_ERROR: File looks valid but contains headers that aren't
+ *     supported by this version of liblzma
+ *   - LZMA_DATA_ERROR: File is corrupt
+ *   - LZMA_BUF_ERROR
+ *   - LZMA_MEM_ERROR
+ *   - LZMA_MEMLIMIT_ERROR
+ *   - LZMA_PROG_ERROR
+ *
+ * \param       strm        Pointer to a properly prepared lzma_stream
+ * \param[out]  dest_index  Pointer to a pointer where the decoder will put
+ *                          the decoded lzma_index. The old value
+ *                          of *dest_index is ignored (not freed).
+ * \param       memlimit    How much memory the resulting lzma_index is
+ *                          allowed to require. Use UINT64_MAX to
+ *                          effectively disable the limiter.
+ * \param       file_size   Size of the input .xz file
+ *
+ * \return      Possible lzma_ret values:
+ *              - LZMA_OK
+ *              - LZMA_MEM_ERROR
+ *              - LZMA_PROG_ERROR
+ */
+extern LZMA_API(lzma_ret) lzma_file_info_decoder(
+		lzma_stream *strm, lzma_index **dest_index,
+		uint64_t memlimit, uint64_t file_size)
+		lzma_nothrow;