X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=lzma%2Fapi%2Flzma%2Findex.h;fp=lzma%2Fapi%2Flzma%2Findex.h;h=dda60ec1c185c5c1f8475122ff35fbcf67f1bb6f;hb=32b8a6b26ed8843828e03e505d2256960bda0980;hp=0000000000000000000000000000000000000000;hpb=d48fc23a4bcf8ca3c406d6e8c8a6f8c6b0fa2f1e;p=zpackage diff --git a/lzma/api/lzma/index.h b/lzma/api/lzma/index.h new file mode 100644 index 0000000..dda60ec --- /dev/null +++ b/lzma/api/lzma/index.h @@ -0,0 +1,682 @@ +/** + * \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 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;