2 * LZ Decompression functions
4 * Copyright 1996 Marcus Meissner
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 * The LZ (Lempel Ziv) decompression was used in win16 installation programs.
23 * It is a simple tabledriven decompression engine, the algorithm is not
24 * documented as far as I know. WINE does not contain a compressor for
27 * The implementation is complete and there have been no reports of failures
32 * o Check whether the return values are correct
40 #include <sys/types.h>
51 #include "wine/unicode.h"
52 #include "wine/debug.h"
54 WINE_DEFAULT_DEBUG_CHANNEL(file);
56 /* The readahead length of the decompressor. Reading single bytes
57 * using _lread() would be SLOW.
61 /* Format of first 14 byte of LZ compressed file */
68 static BYTE LZMagic[8]={'S','Z','D','D',0x88,0xf0,0x27,0x33};
71 HFILE realfd; /* the real filedescriptor */
72 CHAR lastchar; /* the last char of the filename */
74 DWORD reallength; /* the decompressed length of the file */
75 DWORD realcurrent; /* the position the decompressor currently is */
76 DWORD realwanted; /* the position the user wants to read from */
78 BYTE table[0x1000]; /* the rotating LZ table */
79 UINT curtabent; /* CURrent TABle ENTry */
81 BYTE stringlen; /* length and position of current string */
82 DWORD stringpos; /* from stringtable */
85 WORD bytetype; /* bitmask within blocks */
87 BYTE *get; /* GETLEN bytes */
88 DWORD getcur; /* current read */
89 DWORD getlen; /* length last got */
92 #define MAX_LZSTATES 16
93 static struct lzstate *lzstates[MAX_LZSTATES];
95 #define IS_LZ_HANDLE(h) (((h) >= 0x400) && ((h) < 0x400+MAX_LZSTATES))
96 #define GET_LZ_STATE(h) (IS_LZ_HANDLE(h) ? lzstates[(h)-0x400] : NULL)
98 /* reads one compressed byte, including buffering */
99 #define GET(lzs,b) _lzget(lzs,&b)
100 #define GET_FLUSH(lzs) lzs->getcur=lzs->getlen;
103 _lzget(struct lzstate *lzs,BYTE *b) {
104 if (lzs->getcur<lzs->getlen) {
105 *b = lzs->get[lzs->getcur++];
108 int ret = _lread(lzs->realfd,lzs->get,GETLEN);
109 if (ret==HFILE_ERROR)
119 /* internal function, reads lzheader
120 * returns BADINHANDLE for non filedescriptors
121 * return 0 for file not compressed using LZ
122 * return UNKNOWNALG for unknown algorithm
123 * returns lzfileheader in *head
125 static INT read_header(HFILE fd,struct lzfileheader *head)
129 if (_llseek(fd,0,SEEK_SET)==-1)
130 return LZERROR_BADINHANDLE;
132 /* We can't directly read the lzfileheader struct due to
133 * structure element alignment
135 if (_lread(fd,buf,14)<14)
137 memcpy(head->magic,buf,8);
138 memcpy(&(head->compressiontype),buf+8,1);
139 memcpy(&(head->lastchar),buf+9,1);
141 /* FIXME: consider endianess on non-intel architectures */
142 memcpy(&(head->reallength),buf+10,4);
144 if (memcmp(head->magic,LZMagic,8))
146 if (head->compressiontype!='A')
147 return LZERROR_UNKNOWNALG;
152 /***********************************************************************
155 INT WINAPI LZStart(void)
162 /***********************************************************************
165 * initializes internal decompression buffers, returns lzfiledescriptor.
166 * (return value the same as hfSrc, if hfSrc is not compressed)
167 * on failure, returns error code <0
168 * lzfiledescriptors range from 0x400 to 0x410 (only 16 open files per process)
170 * since _llseek uses the same types as libc.lseek, we just use the macros of
173 HFILE WINAPI LZInit( HFILE hfSrc )
176 struct lzfileheader head;
181 TRACE("(%d)\n",hfSrc);
182 ret=read_header(hfSrc,&head);
184 _llseek(hfSrc,0,SEEK_SET);
185 return ret?ret:hfSrc;
187 for (i = 0; i < MAX_LZSTATES; i++) if (!lzstates[i]) break;
188 if (i == MAX_LZSTATES) return LZERROR_GLOBALLOC;
189 lzstates[i] = lzs = HeapAlloc( GetProcessHeap(), 0, sizeof(struct lzstate) );
190 if(lzs == NULL) return LZERROR_GLOBALLOC;
192 memset(lzs,'\0',sizeof(*lzs));
194 lzs->lastchar = head.lastchar;
195 lzs->reallength = head.reallength;
197 lzs->get = HeapAlloc( GetProcessHeap(), 0, GETLEN );
201 if(lzs->get == NULL) {
202 HeapFree(GetProcessHeap(), 0, lzs);
204 return LZERROR_GLOBALLOC;
207 /* Yes, preinitialize with spaces */
208 memset(lzs->table,' ',0x1000);
209 /* Yes, start 16 byte from the END of the table */
210 lzs->curtabent = 0xff0;
215 /***********************************************************************
216 * LZDone (LZEXPAND.9)
219 void WINAPI LZDone(void)
225 /***********************************************************************
226 * GetExpandedNameA (LZ32.@)
228 * gets the full filename of the compressed file 'in' by opening it
229 * and reading the header
231 * "file." is being translated to "file"
232 * "file.bl_" (with lastchar 'a') is being translated to "file.bla"
233 * "FILE.BL_" (with lastchar 'a') is being translated to "FILE.BLA"
236 INT WINAPI GetExpandedNameA( LPSTR in, LPSTR out )
238 struct lzfileheader head;
241 INT fnislowercased,ret,len;
245 fd=OpenFile(in,&ofs,OF_READ);
247 return (INT)(INT16)LZERROR_BADINHANDLE;
249 ret=read_header(fd,&head);
251 /* not a LZ compressed file, so the expanded name is the same
252 * as the input name */
258 /* look for directory prefix and skip it. */
260 while (NULL!=(t=strpbrk(s,"/\\:")))
263 /* now mangle the basename */
265 /* FIXME: hmm. shouldn't happen? */
266 WARN("Specified a directory or what? (%s)\n",in);
270 /* see if we should use lowercase or uppercase on the last char */
278 fnislowercased=islower(*t);
281 if (isalpha(head.lastchar)) {
283 head.lastchar=tolower(head.lastchar);
285 head.lastchar=toupper(head.lastchar);
288 /* now look where to replace the last character */
289 if (NULL!=(t=strchr(s,'.'))) {
295 t[len]=head.lastchar;
297 } /* else no modification necessary */
303 /***********************************************************************
304 * GetExpandedNameW (LZ32.@)
306 INT WINAPI GetExpandedNameW( LPWSTR in, LPWSTR out )
309 DWORD len = WideCharToMultiByte( CP_ACP, 0, in, -1, NULL, 0, NULL, NULL );
310 char *xin = HeapAlloc( GetProcessHeap(), 0, len );
311 char *xout = HeapAlloc( GetProcessHeap(), 0, len+3 );
312 WideCharToMultiByte( CP_ACP, 0, in, -1, xin, len, NULL, NULL );
313 if ((ret = GetExpandedNameA( xin, xout )) > 0)
314 MultiByteToWideChar( CP_ACP, 0, xout, -1, out, strlenW(in)+4 );
315 HeapFree( GetProcessHeap(), 0, xin );
316 HeapFree( GetProcessHeap(), 0, xout );
321 /***********************************************************************
324 INT WINAPI LZRead( HFILE fd, LPSTR vbuf, INT toread )
331 TRACE("(%d,%p,%d)\n",fd,buf,toread);
333 if (!(lzs = GET_LZ_STATE(fd))) return _lread(fd,buf,toread);
335 /* The decompressor itself is in a define, cause we need it twice
336 * in this function. (the decompressed byte will be in b)
338 #define DECOMPRESS_ONE_BYTE \
339 if (lzs->stringlen) { \
340 b = lzs->table[lzs->stringpos]; \
341 lzs->stringpos = (lzs->stringpos+1)&0xFFF; \
344 if (!(lzs->bytetype&0x100)) { \
346 return toread-howmuch; \
347 lzs->bytetype = b|0xFF00; \
349 if (lzs->bytetype & 1) { \
351 return toread-howmuch; \
355 if (1!=GET(lzs,b1)) \
356 return toread-howmuch; \
357 if (1!=GET(lzs,b2)) \
358 return toread-howmuch; \
362 * where CAB is the stringoffset in the table\
363 * and D+3 is the len of the string \
365 lzs->stringpos = b1|((b2&0xf0)<<4); \
366 lzs->stringlen = (b2&0xf)+2; \
367 /* 3, but we use a byte already below ... */\
368 b = lzs->table[lzs->stringpos];\
369 lzs->stringpos = (lzs->stringpos+1)&0xFFF;\
373 /* store b in table */ \
374 lzs->table[lzs->curtabent++]= b; \
375 lzs->curtabent &= 0xFFF; \
378 /* if someone has seeked, we have to bring the decompressor
381 if (lzs->realcurrent!=lzs->realwanted) {
382 /* if the wanted position is before the current position
383 * I see no easy way to unroll ... We have to restart at
384 * the beginning. *sigh*
386 if (lzs->realcurrent>lzs->realwanted) {
387 /* flush decompressor state */
388 _llseek(lzs->realfd,14,SEEK_SET);
393 memset(lzs->table,' ',0x1000);
394 lzs->curtabent = 0xFF0;
396 while (lzs->realcurrent<lzs->realwanted) {
408 #undef DECOMPRESS_ONE_BYTE
412 /***********************************************************************
415 LONG WINAPI LZSeek( HFILE fd, LONG off, INT type )
420 TRACE("(%d,%ld,%d)\n",fd,off,type);
421 /* not compressed? just use normal _llseek() */
422 if (!(lzs = GET_LZ_STATE(fd))) return _llseek(fd,off,type);
423 newwanted = lzs->realwanted;
425 case 1: /* SEEK_CUR */
428 case 2: /* SEEK_END */
429 newwanted = lzs->reallength-off;
431 default:/* SEEK_SET */
435 if (newwanted>lzs->reallength)
436 return LZERROR_BADVALUE;
438 return LZERROR_BADVALUE;
439 lzs->realwanted = newwanted;
444 /***********************************************************************
447 * Copies everything from src to dest
448 * if src is a LZ compressed file, it will be uncompressed.
449 * will return the number of bytes written to dest or errors.
451 LONG WINAPI LZCopy( HFILE src, HFILE dest )
453 int usedlzinit = 0, ret, wret;
455 HFILE oldsrc = src, srcfd;
460 /* we need that weird typedef, for i can't seem to get function pointer
461 * casts right. (Or they probably just do not like WINAPI in general)
463 typedef UINT (WINAPI *_readfun)(HFILE,LPVOID,UINT);
467 TRACE("(%d,%d)\n",src,dest);
468 if (!IS_LZ_HANDLE(src)) {
470 if ((INT)src <= 0) return 0;
471 if (src != oldsrc) usedlzinit=1;
474 /* not compressed? just copy */
475 if (!IS_LZ_HANDLE(src))
478 xread=(_readfun)LZRead;
481 ret=xread(src,buf,BUFLEN);
490 wret = _lwrite(dest,buf,ret);
492 return LZERROR_WRITE;
495 /* Maintain the timestamp of source file to destination file */
496 srcfd = (!(lzs = GET_LZ_STATE(src))) ? src : lzs->realfd;
497 GetFileTime((HANDLE)srcfd, NULL, NULL, &filetime);
498 SetFileTime((HANDLE)dest, NULL, NULL, &filetime);
507 /* reverses GetExpandedPathname */
508 static LPSTR LZEXPAND_MangleName( LPCSTR fn )
511 char *mfn = HeapAlloc( GetProcessHeap(), 0, strlen(fn) + 3 ); /* "._" and \0 */
512 if(mfn == NULL) return NULL;
514 if (!(p = strrchr( mfn, '\\' ))) p = mfn;
515 if ((p = strchr( p, '.' )))
518 if (strlen(p) < 3) strcat( p, "_" ); /* append '_' */
519 else p[strlen(p)-1] = '_'; /* replace last character */
521 else strcat( mfn, "._" ); /* append "._" */
526 /***********************************************************************
527 * LZOpenFileA (LZ32.@)
529 * Opens a file. If not compressed, open it as a normal file.
531 HFILE WINAPI LZOpenFileA( LPSTR fn, LPOFSTRUCT ofs, WORD mode )
535 TRACE("(%s,%p,%d)\n",fn,ofs,mode);
536 /* 0x70 represents all OF_SHARE_* flags, ignore them for the check */
537 fd=OpenFile(fn,ofs,mode);
540 LPSTR mfn = LZEXPAND_MangleName(fn);
541 fd = OpenFile(mfn,ofs,mode);
542 HeapFree( GetProcessHeap(), 0, mfn );
544 if ((mode&~0x70)!=OF_READ)
549 if ((INT)cfd <= 0) return fd;
554 /***********************************************************************
555 * LZOpenFileW (LZ32.@)
557 HFILE WINAPI LZOpenFileW( LPWSTR fn, LPOFSTRUCT ofs, WORD mode )
560 DWORD len = WideCharToMultiByte( CP_ACP, 0, fn, -1, NULL, 0, NULL, NULL );
561 LPSTR xfn = HeapAlloc( GetProcessHeap(), 0, len );
562 WideCharToMultiByte( CP_ACP, 0, fn, -1, xfn, len, NULL, NULL );
563 ret = LZOpenFileA(xfn,ofs,mode);
564 HeapFree( GetProcessHeap(), 0, xfn );
569 /***********************************************************************
572 void WINAPI LZClose( HFILE fd )
577 if (!(lzs = GET_LZ_STATE(fd))) _lclose(fd);
580 HeapFree( GetProcessHeap(), 0, lzs->get );
581 CloseHandle((HANDLE)lzs->realfd);
582 lzstates[fd - 0x400] = NULL;
583 HeapFree( GetProcessHeap(), 0, lzs );
588 /***********************************************************************
589 * CopyLZFile (LZ32.@)
591 * Copy src to dest (including uncompressing src).
592 * NOTE: Yes. This is exactly the same function as LZCopy.
594 LONG WINAPI CopyLZFile( HFILE src, HFILE dest )
596 TRACE("(%d,%d)\n",src,dest);
597 return LZCopy(src,dest);