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668 lines
22 KiB
668 lines
22 KiB
/* This file is part of libmspack.
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* (C) 2003-2004 Stuart Caie.
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*
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* The deflate method was created by Phil Katz. MSZIP is equivalent to the
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* deflate method.
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*
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* libmspack is free software; you can redistribute it and/or modify it under
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* the terms of the GNU Lesser General Public License (LGPL) version 2.1
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*
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* For further details, see the file COPYING.LIB distributed with libmspack
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*/
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/* MS-ZIP decompression implementation. */
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#if HAVE_CONFIG_H
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#include "clamav-config.h"
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#endif
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#include <mspack.h>
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#include <system.h>
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#include <mszip.h>
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#include "others.h"
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/* match lengths for literal codes 257.. 285 */
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static const unsigned short lit_lengths[29] = {
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3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27,
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31, 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258
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};
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/* match offsets for distance codes 0 .. 29 */
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static const unsigned short dist_offsets[30] = {
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1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385,
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513, 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577
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};
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/* extra bits required for literal codes 257.. 285 */
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static const unsigned char lit_extrabits[29] = {
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0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2,
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2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0
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};
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/* extra bits required for distance codes 0 .. 29 */
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static const unsigned char dist_extrabits[30] = {
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0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6,
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6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13
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};
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/* the order of the bit length Huffman code lengths */
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static const unsigned char bitlen_order[19] = {
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16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15
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};
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/* ANDing with bit_mask[n] masks the lower n bits */
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static const unsigned short bit_mask[17] = {
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0x0000, 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
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0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
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};
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#define STORE_BITS do { \
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zip->i_ptr = i_ptr; \
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zip->i_end = i_end; \
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zip->bit_buffer = bit_buffer; \
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zip->bits_left = bits_left; \
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} while (0)
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#define RESTORE_BITS do { \
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i_ptr = zip->i_ptr; \
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i_end = zip->i_end; \
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bit_buffer = zip->bit_buffer; \
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bits_left = zip->bits_left; \
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} while (0)
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#define ENSURE_BITS(nbits) do { \
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while (bits_left < (nbits)) { \
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if (i_ptr >= i_end) { \
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if (zipd_read_input(zip)) return zip->error; \
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i_ptr = zip->i_ptr; \
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i_end = zip->i_end; \
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} \
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bit_buffer |= *i_ptr++ << bits_left; bits_left += 8; \
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} \
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} while (0)
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#define PEEK_BITS(nbits) (bit_buffer & ((1<<(nbits))-1))
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#define PEEK_BITS_T(nbits) (bit_buffer & bit_mask[(nbits)])
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#define REMOVE_BITS(nbits) ((bit_buffer >>= (nbits)), (bits_left -= (nbits)))
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#define READ_BITS(val, nbits) do { \
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ENSURE_BITS(nbits); (val) = PEEK_BITS(nbits); REMOVE_BITS(nbits); \
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} while (0)
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#define READ_BITS_T(val, nbits) do { \
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ENSURE_BITS(nbits); (val) = PEEK_BITS_T(nbits); REMOVE_BITS(nbits); \
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} while (0)
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static int zipd_read_input(struct mszipd_stream *zip) {
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int read = zip->sys->read(zip->input, &zip->inbuf[0], (int)zip->inbuf_size);
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if (read < 0) return zip->error = MSPACK_ERR_READ;
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if (read == 0) {
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if (zip->input_end) {
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D(("out of input bytes"))
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return zip->error = MSPACK_ERR_READ;
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}
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else {
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read = 1;
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zip->inbuf[0] = 0;
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zip->input_end = 1;
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}
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}
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zip->i_ptr = &zip->inbuf[0];
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zip->i_end = &zip->inbuf[read];
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return MSPACK_ERR_OK;
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}
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/* inflate() error codes */
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#define INF_ERR_BLOCKTYPE (-1) /* unknown block type */
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#define INF_ERR_COMPLEMENT (-2) /* block size complement mismatch */
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#define INF_ERR_FLUSH (-3) /* error from flush_window() callback */
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#define INF_ERR_BITBUF (-4) /* too many bits in bit buffer */
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#define INF_ERR_SYMLENS (-5) /* too many symbols in blocktype 2 header */
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#define INF_ERR_BITLENTBL (-6) /* failed to build bitlens huffman table */
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#define INF_ERR_LITERALTBL (-7) /* failed to build literals huffman table */
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#define INF_ERR_DISTANCETBL (-8) /* failed to build distance huffman table */
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#define INF_ERR_BITOVERRUN (-9) /* bitlen RLE code goes over table size */
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#define INF_ERR_BADBITLEN (-10) /* invalid bit-length code */
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#define INF_ERR_LITCODE (-11) /* out-of-range literal code */
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#define INF_ERR_DISTCODE (-12) /* out-of-range distance code */
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#define INF_ERR_DISTANCE (-13) /* somehow, distance is beyond 32k */
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#define INF_ERR_HUFFSYM (-14) /* out of bits decoding huffman symbol */
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/* make_decode_table(nsyms, nbits, length[], table[])
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*
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* This function was coded by David Tritscher. It builds a fast huffman
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* decoding table out of just a canonical huffman code lengths table.
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*
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* NOTE: this is NOT identical to the make_decode_table() in lzxd.c. This
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* one reverses the quick-lookup bit pattern. Bits are read MSB to LSB in LZX,
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* but LSB to MSB in MSZIP.
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*
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* nsyms = total number of symbols in this huffman tree.
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* nbits = any symbols with a code length of nbits or less can be decoded
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* in one lookup of the table.
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* length = A table to get code lengths from [0 to nsyms-1]
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* table = The table to fill up with decoded symbols and pointers.
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*
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* Returns 0 for OK or 1 for error
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*/
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static int make_decode_table(unsigned int nsyms, unsigned int nbits,
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unsigned char *length, unsigned short *table)
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{
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register unsigned int leaf, reverse, fill;
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register unsigned short sym, next_sym;
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register unsigned char bit_num;
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unsigned int pos = 0; /* the current position in the decode table */
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unsigned int table_mask = 1 << nbits;
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unsigned int bit_mask = table_mask >> 1; /* don't do 0 length codes */
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/* fill entries for codes short enough for a direct mapping */
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for (bit_num = 1; bit_num <= nbits; bit_num++) {
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for (sym = 0; sym < nsyms; sym++) {
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if (length[sym] != bit_num) continue;
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/* reverse the significant bits */
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fill = length[sym]; reverse = pos >> (nbits - fill); leaf = 0;
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do {leaf <<= 1; leaf |= reverse & 1; reverse >>= 1;} while (--fill);
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if((pos += bit_mask) > table_mask) return 1; /* table overrun */
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/* fill all possible lookups of this symbol with the symbol itself */
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fill = bit_mask; next_sym = 1 << bit_num;
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do { table[leaf] = sym; leaf += next_sym; } while (--fill);
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}
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bit_mask >>= 1;
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}
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/* exit with success if table is now complete */
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if (pos == table_mask) return 0;
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/* mark all remaining table entries as unused */
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for (sym = pos; sym < table_mask; sym++) {
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reverse = sym; leaf = 0; fill = nbits;
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do { leaf <<= 1; leaf |= reverse & 1; reverse >>= 1; } while (--fill);
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table[leaf] = 0xFFFF;
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}
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/* where should the longer codes be allocated from? */
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next_sym = ((table_mask >> 1) < nsyms) ? nsyms : (table_mask >> 1);
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/* give ourselves room for codes to grow by up to 16 more bits.
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* codes now start at bit nbits+16 and end at (nbits+16-codelength) */
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pos <<= 16;
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table_mask <<= 16;
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bit_mask = 1 << 15;
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for (bit_num = nbits+1; bit_num <= MSZIP_MAX_HUFFBITS; bit_num++) {
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for (sym = 0; sym < nsyms; sym++) {
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if (length[sym] != bit_num) continue;
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/* leaf = the first nbits of the code, reversed */
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reverse = pos >> 16; leaf = 0; fill = nbits;
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do {leaf <<= 1; leaf |= reverse & 1; reverse >>= 1;} while (--fill);
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for (fill = 0; fill < (bit_num - nbits); fill++) {
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/* if this path hasn't been taken yet, 'allocate' two entries */
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if (table[leaf] == 0xFFFF) {
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table[(next_sym << 1) ] = 0xFFFF;
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table[(next_sym << 1) + 1 ] = 0xFFFF;
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table[leaf] = next_sym++;
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}
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/* follow the path and select either left or right for next bit */
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leaf = (table[leaf] << 1) | ((pos >> (15 - fill)) & 1);
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}
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table[leaf] = sym;
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if ((pos += bit_mask) > table_mask) return 1; /* table overflow */
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}
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bit_mask >>= 1;
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}
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/* full table? */
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return (pos != table_mask) ? 1 : 0;
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}
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/* READ_HUFFSYM(tablename, var) decodes one huffman symbol from the
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* bitstream using the stated table and puts it in var.
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*/
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#define READ_HUFFSYM(tbl, var) do { \
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/* huffman symbols can be up to 16 bits long */ \
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ENSURE_BITS(MSZIP_MAX_HUFFBITS); \
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/* immediate table lookup of [tablebits] bits of the code */ \
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sym = zip->tbl##_table[PEEK_BITS(MSZIP_##tbl##_TABLEBITS)]; \
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/* is the symbol is longer than [tablebits] bits? (i=node index) */ \
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if (sym >= MSZIP_##tbl##_MAXSYMBOLS) { \
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/* decode remaining bits by tree traversal */ \
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i = MSZIP_##tbl##_TABLEBITS - 1; \
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do { \
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/* check next bit. error if we run out of bits before decode */ \
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if (i++ > MSZIP_MAX_HUFFBITS) { \
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D(("out of bits in huffman decode")) \
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return INF_ERR_HUFFSYM; \
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} \
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/* double node index and add 0 (left branch) or 1 (right) */ \
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sym = zip->tbl##_table[(sym << 1) | ((bit_buffer >> i) & 1)]; \
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/* while we are still in node indicies, not decoded symbols */ \
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} while (sym >= MSZIP_##tbl##_MAXSYMBOLS); \
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} \
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/* result */ \
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(var) = sym; \
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/* look up the code length of that symbol and discard those bits */ \
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i = zip->tbl##_len[sym]; \
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REMOVE_BITS(i); \
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} while (0)
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static int zip_read_lens(struct mszipd_stream *zip) {
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/* for the bit buffer and huffman decoding */
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register unsigned int bit_buffer;
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register int bits_left;
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unsigned char *i_ptr, *i_end;
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/* bitlen Huffman codes -- immediate lookup, 7 bit max code length */
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unsigned short bl_table[(1 << 7)];
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unsigned char bl_len[19];
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unsigned char lens[MSZIP_LITERAL_MAXSYMBOLS + MSZIP_DISTANCE_MAXSYMBOLS];
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unsigned int lit_codes, dist_codes, code, last_code=0, bitlen_codes, i, run;
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RESTORE_BITS;
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/* read the number of codes */
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READ_BITS(lit_codes, 5); lit_codes += 257;
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READ_BITS(dist_codes, 5); dist_codes += 1;
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READ_BITS(bitlen_codes, 4); bitlen_codes += 4;
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if (lit_codes > MSZIP_LITERAL_MAXSYMBOLS) return INF_ERR_SYMLENS;
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if (dist_codes > MSZIP_DISTANCE_MAXSYMBOLS) return INF_ERR_SYMLENS;
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/* read in the bit lengths in their unusual order */
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for (i = 0; i < bitlen_codes; i++) READ_BITS(bl_len[bitlen_order[i]], 3);
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while (i < 19) bl_len[bitlen_order[i++]] = 0;
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/* create decoding table with an immediate lookup */
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if (make_decode_table(19, 7, &bl_len[0], &bl_table[0])) {
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return INF_ERR_BITLENTBL;
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}
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/* read literal / distance code lengths */
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for (i = 0; i < (lit_codes + dist_codes); i++) {
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/* single-level huffman lookup */
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ENSURE_BITS(7);
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code = bl_table[PEEK_BITS(7)];
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REMOVE_BITS(bl_len[code]);
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if (code < 16) lens[i] = last_code = code;
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else {
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switch (code) {
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case 16: READ_BITS(run, 2); run += 3; code = last_code; break;
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case 17: READ_BITS(run, 3); run += 3; code = 0; break;
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case 18: READ_BITS(run, 7); run += 11; code = 0; break;
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default: D(("bad code!: %u", code)) return INF_ERR_BADBITLEN;
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}
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if ((i + run) > (lit_codes + dist_codes)) return INF_ERR_BITOVERRUN;
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while (run--) lens[i++] = code;
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i--;
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}
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}
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/* copy LITERAL code lengths and clear any remaining */
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i = lit_codes;
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zip->sys->copy(&lens[0], &zip->LITERAL_len[0], i);
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while (i < MSZIP_LITERAL_MAXSYMBOLS) zip->LITERAL_len[i++] = 0;
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i = dist_codes;
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zip->sys->copy(&lens[lit_codes], &zip->DISTANCE_len[0], i);
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while (i < MSZIP_DISTANCE_MAXSYMBOLS) zip->DISTANCE_len[i++] = 0;
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STORE_BITS;
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return 0;
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}
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/* a clean implementation of RFC 1951 / inflate */
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static int inflate(struct mszipd_stream *zip) {
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unsigned int last_block, block_type, distance, length, this_run, i;
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/* for the bit buffer and huffman decoding */
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register unsigned int bit_buffer;
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register int bits_left;
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register unsigned short sym;
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unsigned char *i_ptr, *i_end;
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RESTORE_BITS;
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do {
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/* read in last block bit */
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READ_BITS(last_block, 1);
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/* read in block type */
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READ_BITS(block_type, 2);
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D(("block_type=%u last_block=%u", block_type, last_block))
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if (block_type == 0) {
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/* uncompressed block */
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unsigned char lens_buf[4];
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/* go to byte boundary */
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i = bits_left & 7; REMOVE_BITS(i);
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/* read 4 bytes of data, emptying the bit-buffer if necessary */
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for (i = 0; (bits_left >= 8); i++) {
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if (i == 4) return INF_ERR_BITBUF;
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lens_buf[i] = PEEK_BITS(8);
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REMOVE_BITS(8);
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}
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if (bits_left != 0) return INF_ERR_BITBUF;
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while (i < 4) {
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if (i_ptr >= i_end) {
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if (zipd_read_input(zip)) return zip->error;
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i_ptr = zip->i_ptr;
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i_end = zip->i_end;
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}
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lens_buf[i++] = *i_ptr++;
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}
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/* get the length and its complement */
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length = lens_buf[0] | (lens_buf[1] << 8);
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i = lens_buf[2] | (lens_buf[3] << 8);
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if (length != (~i & 0xFFFF)) return INF_ERR_COMPLEMENT;
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/* read and copy the uncompressed data into the window */
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while (length > 0) {
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if (i_ptr >= i_end) {
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if (zipd_read_input(zip)) return zip->error;
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i_ptr = zip->i_ptr;
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i_end = zip->i_end;
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}
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this_run = length;
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if (this_run > (unsigned int)(i_end - i_ptr)) this_run = i_end - i_ptr;
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if (this_run > (MSZIP_FRAME_SIZE - zip->window_posn))
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this_run = MSZIP_FRAME_SIZE - zip->window_posn;
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zip->sys->copy(i_ptr, &zip->window[zip->window_posn], this_run);
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zip->window_posn += this_run;
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i_ptr += this_run;
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length -= this_run;
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if (zip->window_posn == MSZIP_FRAME_SIZE) {
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if (zip->flush_window(zip, MSZIP_FRAME_SIZE)) return INF_ERR_FLUSH;
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zip->window_posn = 0;
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}
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}
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}
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else if ((block_type == 1) || (block_type == 2)) {
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/* Huffman-compressed LZ77 block */
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unsigned int window_posn, match_posn, code;
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if (block_type == 1) {
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/* block with fixed Huffman codes */
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i = 0;
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while (i < 144) zip->LITERAL_len[i++] = 8;
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while (i < 256) zip->LITERAL_len[i++] = 9;
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while (i < 280) zip->LITERAL_len[i++] = 7;
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while (i < 288) zip->LITERAL_len[i++] = 8;
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for (i = 0; i < 32; i++) zip->DISTANCE_len[i] = 5;
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}
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else {
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/* block with dynamic Huffman codes */
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STORE_BITS;
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if ((i = zip_read_lens(zip))) return i;
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RESTORE_BITS;
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}
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/* now huffman lengths are read for either kind of block,
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* create huffman decoding tables */
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if (make_decode_table(MSZIP_LITERAL_MAXSYMBOLS, MSZIP_LITERAL_TABLEBITS,
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&zip->LITERAL_len[0], &zip->LITERAL_table[0]))
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{
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return INF_ERR_LITERALTBL;
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}
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if (make_decode_table(MSZIP_DISTANCE_MAXSYMBOLS,MSZIP_DISTANCE_TABLEBITS,
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&zip->DISTANCE_len[0], &zip->DISTANCE_table[0]))
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{
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return INF_ERR_DISTANCETBL;
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}
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/* decode forever until end of block code */
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window_posn = zip->window_posn;
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while (1) {
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READ_HUFFSYM(LITERAL, code);
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if (code < 256) {
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zip->window[window_posn++] = (unsigned char) code;
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if (window_posn == MSZIP_FRAME_SIZE) {
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if (zip->flush_window(zip, MSZIP_FRAME_SIZE)) return INF_ERR_FLUSH;
|
|
window_posn = 0;
|
|
}
|
|
}
|
|
else if (code == 256) {
|
|
/* END OF BLOCK CODE: loop break point */
|
|
break;
|
|
}
|
|
else {
|
|
code -= 257;
|
|
if (code > 29) return INF_ERR_LITCODE;
|
|
READ_BITS_T(length, lit_extrabits[code]);
|
|
length += lit_lengths[code];
|
|
|
|
READ_HUFFSYM(DISTANCE, code);
|
|
if (code > 30) return INF_ERR_DISTCODE;
|
|
READ_BITS_T(distance, dist_extrabits[code]);
|
|
distance += dist_offsets[code];
|
|
|
|
/* match position is window position minus distance. If distance
|
|
* is more than window position numerically, it must 'wrap
|
|
* around' the frame size. */
|
|
match_posn = ((distance > window_posn) ? MSZIP_FRAME_SIZE : 0)
|
|
+ window_posn - distance;
|
|
|
|
/* copy match */
|
|
if (length < 12) {
|
|
/* short match, use slower loop but no loop setup code */
|
|
while (length--) {
|
|
zip->window[window_posn++] = zip->window[match_posn++];
|
|
match_posn &= MSZIP_FRAME_SIZE - 1;
|
|
|
|
if (window_posn == MSZIP_FRAME_SIZE) {
|
|
if (zip->flush_window(zip, MSZIP_FRAME_SIZE))
|
|
return INF_ERR_FLUSH;
|
|
window_posn = 0;
|
|
}
|
|
}
|
|
}
|
|
else {
|
|
/* longer match, use faster loop but with setup expense */
|
|
unsigned char *runsrc, *rundest;
|
|
do {
|
|
this_run = length;
|
|
if ((match_posn + this_run) > MSZIP_FRAME_SIZE)
|
|
this_run = MSZIP_FRAME_SIZE - match_posn;
|
|
if ((window_posn + this_run) > MSZIP_FRAME_SIZE)
|
|
this_run = MSZIP_FRAME_SIZE - window_posn;
|
|
|
|
rundest = &zip->window[window_posn]; window_posn += this_run;
|
|
runsrc = &zip->window[match_posn]; match_posn += this_run;
|
|
length -= this_run;
|
|
while (this_run--) *rundest++ = *runsrc++;
|
|
|
|
/* flush if necessary */
|
|
if (window_posn == MSZIP_FRAME_SIZE) {
|
|
if (zip->flush_window(zip, MSZIP_FRAME_SIZE))
|
|
return INF_ERR_FLUSH;
|
|
window_posn = 0;
|
|
}
|
|
if (match_posn == MSZIP_FRAME_SIZE) match_posn = 0;
|
|
} while (length > 0);
|
|
}
|
|
|
|
} /* else (code >= 257) */
|
|
|
|
} /* while (forever) -- break point at 'code == 256' */
|
|
zip->window_posn = window_posn;
|
|
}
|
|
else {
|
|
/* block_type == 3 -- bad block type */
|
|
return INF_ERR_BLOCKTYPE;
|
|
}
|
|
} while (!last_block);
|
|
|
|
/* flush the remaining data */
|
|
if (zip->window_posn) {
|
|
if (zip->flush_window(zip, zip->window_posn)) return INF_ERR_FLUSH;
|
|
}
|
|
STORE_BITS;
|
|
|
|
/* return success */
|
|
return 0;
|
|
}
|
|
|
|
/* inflate() calls this whenever the window should be flushed. As
|
|
* MSZIP only expands to the size of the window, the implementation used
|
|
* simply keeps track of the amount of data flushed, and if more than 32k
|
|
* is flushed, an error is raised.
|
|
*/
|
|
static int mszipd_flush_window(struct mszipd_stream *zip,
|
|
unsigned int data_flushed)
|
|
{
|
|
zip->bytes_output += data_flushed;
|
|
if (zip->bytes_output > MSZIP_FRAME_SIZE) {
|
|
D(("overflow: %u bytes flushed, total is now %u",
|
|
data_flushed, zip->bytes_output))
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
struct mszipd_stream *mszipd_init(struct mspack_system *system,
|
|
struct mspack_file *input,
|
|
struct mspack_file *output,
|
|
int input_buffer_size,
|
|
int repair_mode)
|
|
{
|
|
struct mszipd_stream *zip;
|
|
|
|
if (!system) return NULL;
|
|
|
|
input_buffer_size = (input_buffer_size + 1) & -2;
|
|
if (!input_buffer_size) return NULL;
|
|
|
|
/* allocate decompression state */
|
|
if (!(zip = system->alloc(system, sizeof(struct mszipd_stream)))) {
|
|
return NULL;
|
|
}
|
|
|
|
/* allocate input buffer */
|
|
zip->inbuf = system->alloc(system, (size_t) input_buffer_size);
|
|
if (!zip->inbuf) {
|
|
system->free(zip);
|
|
return NULL;
|
|
}
|
|
|
|
/* initialise decompression state */
|
|
zip->sys = system;
|
|
zip->input = input;
|
|
zip->output = output;
|
|
zip->inbuf_size = input_buffer_size;
|
|
zip->error = MSPACK_ERR_OK;
|
|
zip->repair_mode = repair_mode;
|
|
zip->flush_window = &mszipd_flush_window;
|
|
zip->input_end = 0;
|
|
|
|
zip->i_ptr = zip->i_end = &zip->inbuf[0];
|
|
zip->o_ptr = zip->o_end = NULL;
|
|
zip->bit_buffer = 0; zip->bits_left = 0;
|
|
return zip;
|
|
}
|
|
|
|
int mszipd_decompress(struct mszipd_stream *zip, off_t out_bytes) {
|
|
/* for the bit buffer */
|
|
register unsigned int bit_buffer;
|
|
register int bits_left;
|
|
unsigned char *i_ptr, *i_end;
|
|
|
|
int i, state, error;
|
|
|
|
/* easy answers */
|
|
if (!zip || (out_bytes < 0)) return MSPACK_ERR_ARGS;
|
|
if (zip->error) return zip->error;
|
|
|
|
/* flush out any stored-up bytes before we begin */
|
|
i = zip->o_end - zip->o_ptr;
|
|
if ((off_t) i > out_bytes) i = (int) out_bytes;
|
|
if (i) {
|
|
if (zip->sys->write(zip->output, zip->o_ptr, i) != i) {
|
|
return zip->error = MSPACK_ERR_WRITE;
|
|
}
|
|
zip->o_ptr += i;
|
|
out_bytes -= i;
|
|
}
|
|
if (out_bytes == 0) return MSPACK_ERR_OK;
|
|
|
|
|
|
while (out_bytes > 0) {
|
|
/* unpack another block */
|
|
RESTORE_BITS;
|
|
|
|
/* skip to next read 'CK' header */
|
|
i = bits_left & 7; REMOVE_BITS(i); /* align to bytestream */
|
|
state = 0;
|
|
do {
|
|
READ_BITS(i, 8);
|
|
if (i == 'C') state = 1;
|
|
else if ((state == 1) && (i == 'K')) state = 2;
|
|
else state = 0;
|
|
} while (state != 2);
|
|
|
|
/* inflate a block, repair and realign if necessary */
|
|
zip->window_posn = 0;
|
|
zip->bytes_output = 0;
|
|
STORE_BITS;
|
|
if ((error = inflate(zip))) {
|
|
D(("inflate error %d", i))
|
|
if (zip->repair_mode) {
|
|
zip->sys->message(NULL, "MSZIP error, %u bytes of data lost.",
|
|
MSZIP_FRAME_SIZE - zip->bytes_output);
|
|
for (i = zip->bytes_output; i < MSZIP_FRAME_SIZE; i++) {
|
|
zip->window[i] = '\0';
|
|
}
|
|
zip->bytes_output = MSZIP_FRAME_SIZE;
|
|
}
|
|
else {
|
|
return zip->error = (error > 0) ? error : MSPACK_ERR_DECRUNCH;
|
|
}
|
|
}
|
|
zip->o_ptr = &zip->window[0];
|
|
zip->o_end = &zip->o_ptr[zip->bytes_output];
|
|
|
|
/* write a frame */
|
|
i = (out_bytes < (off_t)zip->bytes_output) ?
|
|
(int)out_bytes : zip->bytes_output;
|
|
if (zip->sys->write(zip->output, zip->o_ptr, i) != i) {
|
|
return zip->error = MSPACK_ERR_WRITE;
|
|
}
|
|
|
|
/* mspack errors (i.e. read errors) are fatal and can't be recovered */
|
|
if ((error > 0) && zip->repair_mode) return error;
|
|
|
|
zip->o_ptr += i;
|
|
out_bytes -= i;
|
|
}
|
|
|
|
if (out_bytes) {
|
|
D(("bytes left to output"))
|
|
return zip->error = MSPACK_ERR_DECRUNCH;
|
|
}
|
|
return MSPACK_ERR_OK;
|
|
}
|
|
|
|
void mszipd_free(struct mszipd_stream *zip) {
|
|
struct mspack_system *sys;
|
|
if (zip) {
|
|
sys = zip->sys;
|
|
sys->free(zip->inbuf);
|
|
sys->free(zip);
|
|
}
|
|
}
|
|
|