/* This file is part of libmspack.
* (C) 2003-2011 Stuart Caie.
*
* KWAJ is a format very similar to SZDD. KWAJ method 3 (LZH) was
* written by Jeff Johnson.
*
* 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
*/
/* KWAJ decompression implementation */
#include <system.h>
#include <kwaj.h>
#include <mszip.h>
/* prototypes */
static struct mskwajd_header *kwajd_open(
struct mskwaj_decompressor *base, const char *filename);
static void kwajd_close(
struct mskwaj_decompressor *base, struct mskwajd_header *hdr);
static int kwajd_read_headers(
struct mspack_system *sys, struct mspack_file *fh,
struct mskwajd_header *hdr);
static int kwajd_extract(
struct mskwaj_decompressor *base, struct mskwajd_header *hdr,
const char *filename);
static int kwajd_decompress(
struct mskwaj_decompressor *base, const char *input, const char *output);
static int kwajd_error(
struct mskwaj_decompressor *base);
static struct kwajd_stream *lzh_init(
struct mspack_system *sys, struct mspack_file *in, struct mspack_file *out);
static int lzh_decompress(
struct kwajd_stream *kwaj);
static void lzh_free(
struct kwajd_stream *kwaj);
static int lzh_read_lens(
struct kwajd_stream *kwaj,
unsigned int type, unsigned int numsyms,
unsigned char *lens);
static int lzh_read_input(
struct kwajd_stream *kwaj);
/***************************************
* MSPACK_CREATE_KWAJ_DECOMPRESSOR
***************************************
* constructor
*/
struct mskwaj_decompressor *
mspack_create_kwaj_decompressor(struct mspack_system *sys)
{
struct mskwaj_decompressor_p *self = NULL;
if (!sys) sys = mspack_default_system;
if (!mspack_valid_system(sys)) return NULL;
if ((self = (struct mskwaj_decompressor_p *) sys->alloc(sys, sizeof(struct mskwaj_decompressor_p)))) {
self->base.open = &kwajd_open;
self->base.close = &kwajd_close;
self->base.extract = &kwajd_extract;
self->base.decompress = &kwajd_decompress;
self->base.last_error = &kwajd_error;
self->system = sys;
self->error = MSPACK_ERR_OK;
}
return (struct mskwaj_decompressor *) self;
}
/***************************************
* MSPACK_DESTROY_KWAJ_DECOMPRESSOR
***************************************
* destructor
*/
void mspack_destroy_kwaj_decompressor(struct mskwaj_decompressor *base)
{
struct mskwaj_decompressor_p *self = (struct mskwaj_decompressor_p *) base;
if (self) {
struct mspack_system *sys = self->system;
sys->free(self);
}
}
/***************************************
* KWAJD_OPEN
***************************************
* opens a KWAJ file without decompressing, reads header
*/
static struct mskwajd_header *kwajd_open(struct mskwaj_decompressor *base,
const char *filename)
{
struct mskwaj_decompressor_p *self = (struct mskwaj_decompressor_p *) base;
struct mskwajd_header *hdr;
struct mspack_system *sys;
struct mspack_file *fh;
if (!self) return NULL;
sys = self->system;
fh = sys->open(sys, filename, MSPACK_SYS_OPEN_READ);
hdr = (struct mskwajd_header *) sys->alloc(sys, sizeof(struct mskwajd_header_p));
if (fh && hdr) {
((struct mskwajd_header_p *) hdr)->fh = fh;
self->error = kwajd_read_headers(sys, fh, hdr);
}
else {
if (!fh) self->error = MSPACK_ERR_OPEN;
if (!hdr) self->error = MSPACK_ERR_NOMEMORY;
}
if (self->error) {
if (fh) sys->close(fh);
sys->free(hdr);
hdr = NULL;
}
return hdr;
}
/***************************************
* KWAJD_CLOSE
***************************************
* closes a KWAJ file
*/
static void kwajd_close(struct mskwaj_decompressor *base,
struct mskwajd_header *hdr)
{
struct mskwaj_decompressor_p *self = (struct mskwaj_decompressor_p *) base;
struct mskwajd_header_p *hdr_p = (struct mskwajd_header_p *) hdr;
if (!self || !self->system) return;
/* close the file handle associated */
self->system->close(hdr_p->fh);
/* free the memory associated */
self->system->free(hdr);
self->error = MSPACK_ERR_OK;
}
/***************************************
* KWAJD_READ_HEADERS
***************************************
* reads the headers of a KWAJ format file
*/
static int kwajd_read_headers(struct mspack_system *sys,
struct mspack_file *fh,
struct mskwajd_header *hdr)
{
unsigned char buf[16];
int i;
/* read in the header */
if (sys->read(fh, &buf[0], kwajh_SIZEOF) != kwajh_SIZEOF) {
return MSPACK_ERR_READ;
}
/* check for "KWAJ" signature */
if (((unsigned int) EndGetI32(&buf[kwajh_Signature1]) != 0x4A41574B) ||
((unsigned int) EndGetI32(&buf[kwajh_Signature2]) != 0xD127F088))
{
return MSPACK_ERR_SIGNATURE;
}
/* basic header fields */
hdr->comp_type = EndGetI16(&buf[kwajh_CompMethod]);
hdr->data_offset = EndGetI16(&buf[kwajh_DataOffset]);
hdr->headers = EndGetI16(&buf[kwajh_Flags]);
hdr->length = 0;
hdr->filename = NULL;
hdr->extra = NULL;
hdr->extra_length = 0;
/* optional headers */
/* 4 bytes: length of unpacked file */
if (hdr->headers & MSKWAJ_HDR_HASLENGTH) {
if (sys->read(fh, &buf[0], 4) != 4) return MSPACK_ERR_READ;
hdr->length = EndGetI32(&buf[0]);
}
/* 2 bytes: unknown purpose */
if (hdr->headers & MSKWAJ_HDR_HASUNKNOWN1) {
if (sys->read(fh, &buf[0], 2) != 2) return MSPACK_ERR_READ;
}
/* 2 bytes: length of section, then [length] bytes: unknown purpose */
if (hdr->headers & MSKWAJ_HDR_HASUNKNOWN2) {
if (sys->read(fh, &buf[0], 2) != 2) return MSPACK_ERR_READ;
i = EndGetI16(&buf[0]);
if (sys->seek(fh, (off_t)i, MSPACK_SYS_SEEK_CUR)) return MSPACK_ERR_SEEK;
}
/* filename and extension */
if (hdr->headers & (MSKWAJ_HDR_HASFILENAME | MSKWAJ_HDR_HASFILEEXT)) {
int len;
/* allocate memory for maximum length filename */
char *fn = (char *) sys->alloc(sys, (size_t) 13);
if (!(hdr->filename = fn)) return MSPACK_ERR_NOMEMORY;
/* copy filename if present */
if (hdr->headers & MSKWAJ_HDR_HASFILENAME) {
/* read and copy up to 9 bytes of a null terminated string */
if ((len = sys->read(fh, &buf[0], 9)) < 2) return MSPACK_ERR_READ;
for (i = 0; i < len; i++) if (!(*fn++ = buf[i])) break;
/* if string was 9 bytes with no null terminator, reject it */
if (i == 9 && buf[8] != '\0') return MSPACK_ERR_DATAFORMAT;
/* seek to byte after string ended in file */
if (sys->seek(fh, (off_t)(i + 1 - len), MSPACK_SYS_SEEK_CUR))
return MSPACK_ERR_SEEK;
fn--; /* remove the null terminator */
}
/* copy extension if present */
if (hdr->headers & MSKWAJ_HDR_HASFILEEXT) {
*fn++ = '.';
/* read and copy up to 4 bytes of a null terminated string */
if ((len = sys->read(fh, &buf[0], 4)) < 2) return MSPACK_ERR_READ;
for (i = 0; i < len; i++) if (!(*fn++ = buf[i])) break;
/* if string was 4 bytes with no null terminator, reject it */
if (i == 4 && buf[3] != '\0') return MSPACK_ERR_DATAFORMAT;
/* seek to byte after string ended in file */
if (sys->seek(fh, (off_t)(i + 1 - len), MSPACK_SYS_SEEK_CUR))
return MSPACK_ERR_SEEK;
fn--; /* remove the null terminator */
}
*fn = '\0';
}
/* 2 bytes: extra text length then [length] bytes of extra text data */
if (hdr->headers & MSKWAJ_HDR_HASEXTRATEXT) {
if (sys->read(fh, &buf[0], 2) != 2) return MSPACK_ERR_READ;
i = EndGetI16(&buf[0]);
hdr->extra = (char *) sys->alloc(sys, (size_t)i+1);
if (! hdr->extra) return MSPACK_ERR_NOMEMORY;
if (sys->read(fh, hdr->extra, i) != i) return MSPACK_ERR_READ;
hdr->extra[i] = '\0';
hdr->extra_length = i;
}
return MSPACK_ERR_OK;
}
/***************************************
* KWAJD_EXTRACT
***************************************
* decompresses a KWAJ file
*/
static int kwajd_extract(struct mskwaj_decompressor *base,
struct mskwajd_header *hdr, const char *filename)
{
struct mskwaj_decompressor_p *self = (struct mskwaj_decompressor_p *) base;
struct mspack_system *sys;
struct mspack_file *fh, *outfh;
if (!self) return MSPACK_ERR_ARGS;
if (!hdr) return self->error = MSPACK_ERR_ARGS;
sys = self->system;
fh = ((struct mskwajd_header_p *) hdr)->fh;
/* seek to the compressed data */
if (sys->seek(fh, hdr->data_offset, MSPACK_SYS_SEEK_START)) {
return self->error = MSPACK_ERR_SEEK;
}
/* open file for output */
if (!(outfh = sys->open(sys, filename, MSPACK_SYS_OPEN_WRITE))) {
return self->error = MSPACK_ERR_OPEN;
}
self->error = MSPACK_ERR_OK;
/* decompress based on format */
if (hdr->comp_type == MSKWAJ_COMP_NONE ||
hdr->comp_type == MSKWAJ_COMP_XOR)
{
/* NONE is a straight copy. XOR is a copy xored with 0xFF */
unsigned char *buf = (unsigned char *) sys->alloc(sys, (size_t) KWAJ_INPUT_SIZE);
if (buf) {
int read, i;
while ((read = sys->read(fh, buf, KWAJ_INPUT_SIZE)) > 0) {
if (hdr->comp_type == MSKWAJ_COMP_XOR) {
for (i = 0; i < read; i++) buf[i] ^= 0xFF;
}
if (sys->write(outfh, buf, read) != read) {
self->error = MSPACK_ERR_WRITE;
break;
}
}
if (read < 0) self->error = MSPACK_ERR_READ;
sys->free(buf);
}
else {
self->error = MSPACK_ERR_NOMEMORY;
}
}
else if (hdr->comp_type == MSKWAJ_COMP_SZDD) {
self->error = lzss_decompress(sys, fh, outfh, KWAJ_INPUT_SIZE,
LZSS_MODE_EXPAND);
}
else if (hdr->comp_type == MSKWAJ_COMP_LZH) {
struct kwajd_stream *lzh = lzh_init(sys, fh, outfh);
self->error = (lzh) ? lzh_decompress(lzh) : MSPACK_ERR_NOMEMORY;
lzh_free(lzh);
}
else if (hdr->comp_type == MSKWAJ_COMP_MSZIP) {
struct mszipd_stream *zip = mszipd_init(sys,fh,outfh,KWAJ_INPUT_SIZE,0);
self->error = (zip) ? mszipd_decompress_kwaj(zip) : MSPACK_ERR_NOMEMORY;
mszipd_free(zip);
}
else {
self->error = MSPACK_ERR_DATAFORMAT;
}
/* close output file */
sys->close(outfh);
return self->error;
}
/***************************************
* KWAJD_DECOMPRESS
***************************************
* unpacks directly from input to output
*/
static int kwajd_decompress(struct mskwaj_decompressor *base,
const char *input, const char *output)
{
struct mskwaj_decompressor_p *self = (struct mskwaj_decompressor_p *) base;
struct mskwajd_header *hdr;
int error;
if (!self) return MSPACK_ERR_ARGS;
if (!(hdr = kwajd_open(base, input))) return self->error;
error = kwajd_extract(base, hdr, output);
kwajd_close(base, hdr);
return self->error = error;
}
/***************************************
* KWAJD_ERROR
***************************************
* returns the last error that occurred
*/
static int kwajd_error(struct mskwaj_decompressor *base)
{
struct mskwaj_decompressor_p *self = (struct mskwaj_decompressor_p *) base;
return (self) ? self->error : MSPACK_ERR_ARGS;
}
/***************************************
* LZH_INIT, LZH_DECOMPRESS, LZH_FREE
***************************************
* unpacks KWAJ method 3 files
*/
/* import bit-reading macros and code */
#define BITS_TYPE struct kwajd_stream
#define BITS_VAR lzh
#define BITS_ORDER_MSB
#define BITS_NO_READ_INPUT
#define READ_BYTES do { \
if (i_ptr >= i_end) { \
if ((err = lzh_read_input(lzh))) return err; \
i_ptr = lzh->i_ptr; \
i_end = lzh->i_end; \
} \
INJECT_BITS(*i_ptr++, 8); \
} while (0)
#include <readbits.h>
/* import huffman-reading macros and code */
#define TABLEBITS(tbl) KWAJ_TABLEBITS
#define MAXSYMBOLS(tbl) KWAJ_##tbl##_SYMS
#define HUFF_TABLE(tbl,idx) lzh->tbl##_table[idx]
#define HUFF_LEN(tbl,idx) lzh->tbl##_len[idx]
#define HUFF_ERROR return MSPACK_ERR_DATAFORMAT
#include <readhuff.h>
/* In the KWAJ LZH format, there is no special 'eof' marker, it just
* ends. Depending on how many bits are left in the final byte when
* the stream ends, that might be enough to start another literal or
* match. The only easy way to detect that we've come to an end is to
* guard all bit-reading. We allow fake bits to be read once we reach
* the end of the stream, but we check if we then consumed any of
* those fake bits, after doing the READ_BITS / READ_HUFFSYM. This
* isn't how the default readbits.h read_input() works (it simply lets
* 2 fake bytes in then stops), so we implement our own.
*/
#define READ_BITS_SAFE(val, n) do { \
READ_BITS(val, n); \
if (lzh->input_end && bits_left < lzh->input_end) \
return MSPACK_ERR_OK; \
} while (0)
#define READ_HUFFSYM_SAFE(tbl, val) do { \
READ_HUFFSYM(tbl, val); \
if (lzh->input_end && bits_left < lzh->input_end) \
return MSPACK_ERR_OK; \
} while (0)
#define BUILD_TREE(tbl, type) \
STORE_BITS; \
err = lzh_read_lens(lzh, type, MAXSYMBOLS(tbl), &HUFF_LEN(tbl,0)); \
if (err) return err; \
RESTORE_BITS; \
if (make_decode_table(MAXSYMBOLS(tbl), TABLEBITS(tbl), \
&HUFF_LEN(tbl,0), &HUFF_TABLE(tbl,0))) \
return MSPACK_ERR_DATAFORMAT;
#define WRITE_BYTE do { \
if (lzh->sys->write(lzh->output, &lzh->window[pos], 1) != 1) \
return MSPACK_ERR_WRITE; \
} while (0)
static struct kwajd_stream *lzh_init(struct mspack_system *sys,
struct mspack_file *in, struct mspack_file *out)
{
struct kwajd_stream *lzh;
if (!sys || !in || !out) return NULL;
if (!(lzh = (struct kwajd_stream *) sys->alloc(sys, sizeof(struct kwajd_stream)))) return NULL;
lzh->sys = sys;
lzh->input = in;
lzh->output = out;
return lzh;
}
static int lzh_decompress(struct kwajd_stream *lzh)
{
register unsigned int bit_buffer;
register int bits_left, i;
register unsigned short sym;
unsigned char *i_ptr, *i_end, lit_run = 0;
int j, pos = 0, len, offset, err;
unsigned int types[6];
/* reset global state */
INIT_BITS;
RESTORE_BITS;
memset(&lzh->window[0], LZSS_WINDOW_FILL, (size_t) LZSS_WINDOW_SIZE);
/* read 6 encoding types (for byte alignment) but only 5 are needed */
for (i = 0; i < 6; i++) READ_BITS_SAFE(types[i], 4);
/* read huffman table symbol lengths and build huffman trees */
BUILD_TREE(MATCHLEN1, types[0]);
BUILD_TREE(MATCHLEN2, types[1]);
BUILD_TREE(LITLEN, types[2]);
BUILD_TREE(OFFSET, types[3]);
BUILD_TREE(LITERAL, types[4]);
while (!lzh->input_end) {
if (lit_run) READ_HUFFSYM_SAFE(MATCHLEN2, len);
else READ_HUFFSYM_SAFE(MATCHLEN1, len);
if (len > 0) {
len += 2;
lit_run = 0; /* not the end of a literal run */
READ_HUFFSYM_SAFE(OFFSET, j); offset = j << 6;
READ_BITS_SAFE(j, 6); offset |= j;
/* copy match as output and into the ring buffer */
while (len-- > 0) {
lzh->window[pos] = lzh->window[(pos+4096-offset) & 4095];
WRITE_BYTE;
pos++; pos &= 4095;
}
}
else {
READ_HUFFSYM_SAFE(LITLEN, len); len++;
lit_run = (len == 32) ? 0 : 1; /* end of a literal run? */
while (len-- > 0) {
READ_HUFFSYM_SAFE(LITERAL, j);
/* copy as output and into the ring buffer */
lzh->window[pos] = j;
WRITE_BYTE;
pos++; pos &= 4095;
}
}
}
return MSPACK_ERR_OK;
}
static void lzh_free(struct kwajd_stream *lzh)
{
struct mspack_system *sys;
if (!lzh || !lzh->sys) return;
sys = lzh->sys;
sys->free(lzh);
}
static int lzh_read_lens(struct kwajd_stream *lzh,
unsigned int type, unsigned int numsyms,
unsigned char *lens)
{
register unsigned int bit_buffer;
register int bits_left;
unsigned char *i_ptr, *i_end;
unsigned int i, c, sel;
int err;
RESTORE_BITS;
switch (type) {
case 0:
i = numsyms; c = (i==16)?4: (i==32)?5: (i==64)?6: (i==256)?8 :0;
for (i = 0; i < numsyms; i++) lens[i] = c;
break;
case 1:
READ_BITS_SAFE(c, 4); lens[0] = c;
for (i = 1; i < numsyms; i++) {
READ_BITS_SAFE(sel, 1); if (sel == 0) lens[i] = c;
else { READ_BITS_SAFE(sel, 1); if (sel == 0) lens[i] = ++c;
else { READ_BITS_SAFE(c, 4); lens[i] = c; }}
}
break;
case 2:
READ_BITS_SAFE(c, 4); lens[0] = c;
for (i = 1; i < numsyms; i++) {
READ_BITS_SAFE(sel, 2);
if (sel == 3) READ_BITS_SAFE(c, 4); else c += (char) sel-1;
lens[i] = c;
}
break;
case 3:
for (i = 0; i < numsyms; i++) {
READ_BITS_SAFE(c, 4); lens[i] = c;
}
break;
}
STORE_BITS;
return MSPACK_ERR_OK;
}
static int lzh_read_input(struct kwajd_stream *lzh) {
int read;
if (lzh->input_end) {
lzh->input_end += 8;
lzh->inbuf[0] = 0;
read = 1;
}
else {
read = lzh->sys->read(lzh->input, &lzh->inbuf[0], KWAJ_INPUT_SIZE);
if (read < 0) return MSPACK_ERR_READ;
if (read == 0) {
lzh->input_end = 8;
lzh->inbuf[0] = 0;
read = 1;
}
}
/* update i_ptr and i_end */
lzh->i_ptr = &lzh->inbuf[0];
lzh->i_end = &lzh->inbuf[read];
return MSPACK_ERR_OK;
}