--- /dev/null
+/**
+ * \file lzma/index.h
+ * \brief Handling of .xz Index and related information
+ */
+
+/*
+ * Author: Lasse Collin
+ *
+ * This file has been put into the public domain.
+ * You can do whatever you want with this file.
+ *
+ * See ../lzma.h for information about liblzma as a whole.
+ */
+
+#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;
+
+ const void *reserved_ptr1;
+ const void *reserved_ptr2;
+ 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;
+
+ lzma_vli reserved_vli1;
+ lzma_vli reserved_vli2;
+ lzma_vli reserved_vli3;
+ 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;
+
+ lzma_vli reserved_vli1;
+ lzma_vli reserved_vli2;
+ lzma_vli reserved_vli3;
+ lzma_vli reserved_vli4;
+
+ const void *reserved_ptr1;
+ const void *reserved_ptr2;
+ const void *reserved_ptr3;
+ const void *reserved_ptr4;
+ } block;
+
+ /*
+ * 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 {
+ const void *p;
+ size_t s;
+ 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 Calculate memory usage of lzma_index
+ *
+ * On disk, the size of the Index field depends on both the number of Records
+ * stored and how big values the Records store (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 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.
+ */
+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)).
+ */
+extern LZMA_API(uint64_t) lzma_index_memused(const lzma_index *i)
+ lzma_nothrow;
+
+
+/**
+ * \brief Allocate and initialize a new lzma_index structure
+ *
+ * \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.
+ */
+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 Pointer to lzma_allocator, or NULL to
+ * use malloc()
+ * \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 - 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.
+ *
+ * The given Stream Flags are copied into internal preallocated structure
+ * in the lzma_index, thus the caller doesn't need to keep the *stream_flags
+ * available after calling this function.
+ *
+ * \return - 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.
+ */
+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 - 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
+ */
+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.
+ */
+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.
+ */
+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.
+ */
+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.
+ */
+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.
+ */
+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
+ */
+extern LZMA_API(lzma_vli) lzma_index_uncompressed_size(const lzma_index *i)
+ lzma_nothrow lzma_attr_pure;
+
+
+/**
+ * \brief Initialize an iterator
+ *
+ * \param iter Pointer to a lzma_index_iter structure
+ * \param i lzma_index to which the iterator will be associated
+ *
+ * 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.
+ */
+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.
+ */
+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 If next Block or Stream matching the mode was found, *iter
+ * is updated and this function returns false. If no Block or
+ * Stream matching the mode is found, *iter is not modified
+ * and this function returns true. If mode is set to an unknown
+ * value, *iter is not modified and this function returns true.
+ */
+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.
+ *
+ * \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
+ *
+ * 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.
+ * - This function returns false.
+ *
+ * If target is greater than the uncompressed size of the Stream, *iter
+ * is not modified, and this function returns true.
+ */
+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 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 Custom memory allocator; can be NULL to use
+ * malloc() and free().
+ *
+ * \return - 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
+ *
+ * \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; use LZMA_RUN
+ * to support liblzma versions older than 5.0.0).
+ *
+ * \return - 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 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.
+ *
+ * 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; use LZMA_RUN
+ * to support liblzma versions older than 5.0.0).
+ *
+ * \return - LZMA_OK: Initialization succeeded, continue with lzma_code().
+ * - LZMA_MEM_ERROR
+ * - LZMA_MEMLIMIT_ERROR
+ * - LZMA_PROG_ERROR
+ */
+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
+ *
+ * \param i lzma_index to be encoded
+ * \param out Beginning of the output buffer
+ * \param 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 - 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
+ *
+ * \note This function doesn't take allocator argument since all
+ * the internal data is allocated on stack.
+ */
+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 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 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 Pointer to lzma_allocator, or NULL to use malloc()
+ * \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 - 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;
projects / zpackage / blobdiff