/**
* \file lzma/index.h
* \brief Handling of Index lists
*
* \author Copyright (C) 1999-2006 Igor Pavlov
* \author Copyright (C) 2007 Lasse Collin
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*/
#ifndef LZMA_H_INTERNAL
# error Never include this file directly. Use <lzma.h> instead.
#endif
/**
* \brief Opaque data type to hold the Index
*/
typedef struct lzma_index_s lzma_index;
/**
* \brief Index Record and its location
*/
typedef struct {
/**
* Total Size of a Block.
*/
lzma_vli total_size;
/**
* Uncompressed Size of a Block
*/
lzma_vli uncompressed_size;
/**
* Offset of the first byte of a Block relative to the beginning
* of the Stream, or if there are multiple Indexes combined,
* relative to the beginning of the first Stream.
*/
lzma_vli stream_offset;
/**
* Uncompressed offset
*/
lzma_vli uncompressed_offset;
} lzma_index_record;
/**
* \brief Allocate and initialize a new lzma_index structure
*
* If i is NULL, a new lzma_index structure is allocated, initialized,
* and a pointer to it returned. If allocation fails, NULL is returned.
*
* If i is non-NULL, it is reinitialized and the same pointer returned.
* In this case, return value cannot be NULL or a different pointer than
* the i given as argument.
*/
extern lzma_index *lzma_index_init(lzma_index *i, lzma_allocator *allocator);
/**
* \brief Deallocate the Index
*/
extern void lzma_index_end(lzma_index *i, lzma_allocator *allocator);
/**
* \brief Add a new Record to an Index
*
* \param index Pointer to a lzma_index structure
* \param total_size Total Size of a Block
* \param uncompressed_size Uncompressed Size of a Block, or
* LZMA_VLI_VALUE_UNKNOWN to indicate padding.
*
* Appending a new Record does not affect the read position.
*
* \return - LZMA_OK
* - 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_ret lzma_index_append(lzma_index *i, lzma_allocator *allocator,
lzma_vli total_size, lzma_vli uncompressed_size);
/**
* \brief Get the number of Records
*/
extern lzma_vli lzma_index_count(const lzma_index *i);
/**
* \brief Get the size of the Index field as bytes
*
* This is needed to verify the Index Size field from the Stream Footer.
*/
extern lzma_vli lzma_index_size(const lzma_index *i);
/**
* \brief Get the total size of the Blocks
*
* This doesn't include the Stream Header, Stream Footer, Stream Padding,
* or Index fields.
*/
extern lzma_vli lzma_index_total_size(const lzma_index *i);
/**
* \brief Get the total size of the Stream
*
* If multiple Indexes have been combined, this works as if the Blocks
* were in a single Stream.
*/
extern lzma_vli lzma_index_stream_size(const lzma_index *i);
/**
* \brief Get the total size of the file
*
* When no Indexes have been combined with lzma_index_cat(), this function is
* identical to lzma_index_stream_size(). If multiple Indexes have been
* combined, this includes also the possible Stream Padding fields.
*/
extern lzma_vli lzma_index_file_size(const lzma_index *i);
/**
* \brief Get the uncompressed size of the Stream
*/
extern lzma_vli lzma_index_uncompressed_size(const lzma_index *i);
/**
* \brief Get the next Record from the Index
*/
extern lzma_bool lzma_index_read(lzma_index *i, lzma_index_record *record);
/**
* \brief Rewind the Index
*
* Rewind the Index so that next call to lzma_index_read() will return the
* first Record.
*/
extern void lzma_index_rewind(lzma_index *i);
/**
* \brief Locate a Record
*
* When the Index is available, it is possible to do random-access reading
* with granularity of Block size.
*
* \param i Pointer to lzma_index structure
* \param record Pointer to a structure to hold the search results
* \param target Uncompressed target offset
*
* If the target is smaller than the uncompressed size of the Stream (can be
* checked with lzma_index_uncompressed_size()):
* - Information about the Record containing the requested uncompressed
* offset is stored into *record.
* - Read offset will be adjusted so that calling lzma_index_read() can be
* used to read subsequent Records.
* - This function returns false.
*
* If target is greater than the uncompressed size of the Stream, *record
* and the read position are not modified, and this function returns true.
*/
extern lzma_bool lzma_index_locate(
lzma_index *i, lzma_index_record *record, lzma_vli target);
/**
* \brief Concatenate Indexes of two Streams
*
*
*
* \param dest Destination Index after which src is appended Source
* \param src Index. The memory allocated for this is either moved
* to be part of *dest or freed iff the function call
* succeeds, and src will be an invalid pointer.
* \param allocator Custom memory allocator; can be NULL to use
* malloc() and free().
* \param padding Size of the Stream Padding field between Streams.
*
* \return - LZMA_OK: Indexes concatenated successfully.
* - LZMA_DATA_ERROR: *dest would grow too big.
* - LZMA_MEM_ERROR
* - LZMA_PROG_ERROR
*/
extern lzma_ret lzma_index_cat(lzma_index *lzma_restrict dest,
lzma_index *lzma_restrict src,
lzma_allocator *allocator, lzma_vli padding);
/**
* \brief Duplicates an Index list
*
* \return A copy of the Index, or NULL if memory allocation failed.
*/
extern lzma_index *lzma_index_dup(
const lzma_index *i, lzma_allocator *allocator);
/**
* \brief Compares if two Index lists are identical
*/
extern lzma_bool lzma_index_equal(const lzma_index *a, const lzma_index *b);
/**
* \brief Initializes Index encoder
*/
extern lzma_ret lzma_index_encoder(lzma_stream *strm, lzma_index *i);
/**
* \brief Initializes Index decoder
*/
extern lzma_ret lzma_index_decoder(lzma_stream *strm, lzma_index **i);
