rockbox/utils/rbutilqt/mspack/mszip.h
Dominik Riebeling c876d3bbef rbutil: Merge rbutil with utils folder.
rbutil uses several components from the utils folder, and can be
considered part of utils too. Having it in a separate folder is an
arbitrary split that doesn't help anymore these days, so merge them.

This also allows other utils to easily use libtools.make without the
need to navigate to a different folder.

Change-Id: I3fc2f4de19e3e776553efb5dea5f779dfec0dc21
2021-12-24 18:05:53 +01:00

126 lines
4.6 KiB
C

/* This file is part of libmspack.
* (C) 2003-2004 Stuart Caie.
*
* The deflate method was created by Phil Katz. MSZIP is equivalent to the
* deflate method.
*
* libmspack is free software; you can redistribute it and/or modify it under
* the terms of the GNU Lesser General Public License (LGPL) version 2.1
*
* For further details, see the file COPYING.LIB distributed with libmspack
*/
#ifndef MSPACK_MSZIP_H
#define MSPACK_MSZIP_H 1
#ifdef __cplusplus
extern "C" {
#endif
/* MSZIP (deflate) compression / (inflate) decompression definitions */
#define MSZIP_FRAME_SIZE (32768) /* size of LZ history window */
#define MSZIP_LITERAL_MAXSYMBOLS (288) /* literal/length huffman tree */
#define MSZIP_LITERAL_TABLEBITS (9)
#define MSZIP_DISTANCE_MAXSYMBOLS (32) /* distance huffman tree */
#define MSZIP_DISTANCE_TABLEBITS (6)
/* if there are less direct lookup entries than symbols, the longer
* code pointers will be <= maxsymbols. This must not happen, or we
* will decode entries badly */
#if (1 << MSZIP_LITERAL_TABLEBITS) < (MSZIP_LITERAL_MAXSYMBOLS * 2)
# define MSZIP_LITERAL_TABLESIZE (MSZIP_LITERAL_MAXSYMBOLS * 4)
#else
# define MSZIP_LITERAL_TABLESIZE ((1 << MSZIP_LITERAL_TABLEBITS) + \
(MSZIP_LITERAL_MAXSYMBOLS * 2))
#endif
#if (1 << MSZIP_DISTANCE_TABLEBITS) < (MSZIP_DISTANCE_MAXSYMBOLS * 2)
# define MSZIP_DISTANCE_TABLESIZE (MSZIP_DISTANCE_MAXSYMBOLS * 4)
#else
# define MSZIP_DISTANCE_TABLESIZE ((1 << MSZIP_DISTANCE_TABLEBITS) + \
(MSZIP_DISTANCE_MAXSYMBOLS * 2))
#endif
struct mszipd_stream {
struct mspack_system *sys; /* I/O routines */
struct mspack_file *input; /* input file handle */
struct mspack_file *output; /* output file handle */
unsigned int window_posn; /* offset within window */
/* inflate() will call this whenever the window should be emptied. */
int (*flush_window)(struct mszipd_stream *, unsigned int);
int error, repair_mode, bytes_output;
/* I/O buffering */
unsigned char *inbuf, *i_ptr, *i_end, *o_ptr, *o_end, input_end;
unsigned int bit_buffer, bits_left, inbuf_size;
/* huffman code lengths */
unsigned char LITERAL_len[MSZIP_LITERAL_MAXSYMBOLS];
unsigned char DISTANCE_len[MSZIP_DISTANCE_MAXSYMBOLS];
/* huffman decoding tables */
unsigned short LITERAL_table [MSZIP_LITERAL_TABLESIZE];
unsigned short DISTANCE_table[MSZIP_DISTANCE_TABLESIZE];
/* 32kb history window */
unsigned char window[MSZIP_FRAME_SIZE];
};
/* allocates MS-ZIP decompression stream for decoding the given stream.
*
* - uses system->alloc() to allocate memory
*
* - returns NULL if not enough memory
*
* - input_buffer_size is how many bytes to use as an input bitstream buffer
*
* - if repair_mode is non-zero, errors in decompression will be skipped
* and 'holes' left will be filled with zero bytes. This allows at least
* a partial recovery of erroneous data.
*/
extern struct mszipd_stream *mszipd_init(struct mspack_system *system,
struct mspack_file *input,
struct mspack_file *output,
int input_buffer_size,
int repair_mode);
/* decompresses, or decompresses more of, an MS-ZIP stream.
*
* - out_bytes of data will be decompressed and the function will return
* with an MSPACK_ERR_OK return code.
*
* - decompressing will stop as soon as out_bytes is reached. if the true
* amount of bytes decoded spills over that amount, they will be kept for
* a later invocation of mszipd_decompress().
*
* - the output bytes will be passed to the system->write() function given in
* mszipd_init(), using the output file handle given in mszipd_init(). More
* than one call may be made to system->write()
*
* - MS-ZIP will read input bytes as necessary using the system->read()
* function given in mszipd_init(), using the input file handle given in
* mszipd_init(). This will continue until system->read() returns 0 bytes,
* or an error.
*/
extern int mszipd_decompress(struct mszipd_stream *zip, off_t out_bytes);
/* decompresses an entire MS-ZIP stream in a KWAJ file. Acts very much
* like mszipd_decompress(), but doesn't take an out_bytes parameter
*/
extern int mszipd_decompress_kwaj(struct mszipd_stream *zip);
/* frees all stream associated with an MS-ZIP data stream
*
* - calls system->free() using the system pointer given in mszipd_init()
*/
void mszipd_free(struct mszipd_stream *zip);
#ifdef __cplusplus
}
#endif
#endif