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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, 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 /***********************************************************************
153 * LZStart (KERNEL32.@)
155 INT WINAPI LZStart(void)
162 /***********************************************************************
163 * LZInit (KERNEL32.@)
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 (KERNEL32.@)
218 void WINAPI LZDone(void)
224 /***********************************************************************
225 * GetExpandedNameA (KERNEL32.@)
227 * gets the full filename of the compressed file 'in' by opening it
228 * and reading the header
230 * "file." is being translated to "file"
231 * "file.bl_" (with lastchar 'a') is being translated to "file.bla"
232 * "FILE.BL_" (with lastchar 'a') is being translated to "FILE.BLA"
235 INT WINAPI GetExpandedNameA( LPSTR in, LPSTR out )
237 struct lzfileheader head;
240 INT fnislowercased,ret,len;
244 fd=OpenFile(in,&ofs,OF_READ);
246 return (INT)(INT16)LZERROR_BADINHANDLE;
248 ret=read_header(fd,&head);
250 /* not a LZ compressed file, so the expanded name is the same
251 * as the input name */
257 /* look for directory prefix and skip it. */
259 while (NULL!=(t=strpbrk(s,"/\\:")))
262 /* now mangle the basename */
264 /* FIXME: hmm. shouldn't happen? */
265 WARN("Specified a directory or what? (%s)\n",in);
269 /* see if we should use lowercase or uppercase on the last char */
277 fnislowercased=islower(*t);
280 if (isalpha(head.lastchar)) {
282 head.lastchar=tolower(head.lastchar);
284 head.lastchar=toupper(head.lastchar);
287 /* now look where to replace the last character */
288 if (NULL!=(t=strchr(s,'.'))) {
294 t[len]=head.lastchar;
296 } /* else no modification necessary */
302 /***********************************************************************
303 * GetExpandedNameW (KERNEL32.@)
305 INT WINAPI GetExpandedNameW( LPWSTR in, LPWSTR out )
308 DWORD len = WideCharToMultiByte( CP_ACP, 0, in, -1, NULL, 0, NULL, NULL );
309 char *xin = HeapAlloc( GetProcessHeap(), 0, len );
310 char *xout = HeapAlloc( GetProcessHeap(), 0, len+3 );
311 WideCharToMultiByte( CP_ACP, 0, in, -1, xin, len, NULL, NULL );
312 if ((ret = GetExpandedNameA( xin, xout )) > 0)
313 MultiByteToWideChar( CP_ACP, 0, xout, -1, out, strlenW(in)+4 );
314 HeapFree( GetProcessHeap(), 0, xin );
315 HeapFree( GetProcessHeap(), 0, xout );
320 /***********************************************************************
321 * LZRead (KERNEL32.@)
323 INT WINAPI LZRead( HFILE fd, LPSTR vbuf, INT toread )
330 TRACE("(%d,%p,%d)\n",fd,buf,toread);
332 if (!(lzs = GET_LZ_STATE(fd))) return _lread(fd,buf,toread);
334 /* The decompressor itself is in a define, cause we need it twice
335 * in this function. (the decompressed byte will be in b)
337 #define DECOMPRESS_ONE_BYTE \
338 if (lzs->stringlen) { \
339 b = lzs->table[lzs->stringpos]; \
340 lzs->stringpos = (lzs->stringpos+1)&0xFFF; \
343 if (!(lzs->bytetype&0x100)) { \
345 return toread-howmuch; \
346 lzs->bytetype = b|0xFF00; \
348 if (lzs->bytetype & 1) { \
350 return toread-howmuch; \
354 if (1!=GET(lzs,b1)) \
355 return toread-howmuch; \
356 if (1!=GET(lzs,b2)) \
357 return toread-howmuch; \
361 * where CAB is the stringoffset in the table\
362 * and D+3 is the len of the string \
364 lzs->stringpos = b1|((b2&0xf0)<<4); \
365 lzs->stringlen = (b2&0xf)+2; \
366 /* 3, but we use a byte already below ... */\
367 b = lzs->table[lzs->stringpos];\
368 lzs->stringpos = (lzs->stringpos+1)&0xFFF;\
372 /* store b in table */ \
373 lzs->table[lzs->curtabent++]= b; \
374 lzs->curtabent &= 0xFFF; \
377 /* if someone has seeked, we have to bring the decompressor
380 if (lzs->realcurrent!=lzs->realwanted) {
381 /* if the wanted position is before the current position
382 * I see no easy way to unroll ... We have to restart at
383 * the beginning. *sigh*
385 if (lzs->realcurrent>lzs->realwanted) {
386 /* flush decompressor state */
387 _llseek(lzs->realfd,14,SEEK_SET);
392 memset(lzs->table,' ',0x1000);
393 lzs->curtabent = 0xFF0;
395 while (lzs->realcurrent<lzs->realwanted) {
407 #undef DECOMPRESS_ONE_BYTE
411 /***********************************************************************
412 * LZSeek (KERNEL32.@)
414 LONG WINAPI LZSeek( HFILE fd, LONG off, INT type )
419 TRACE("(%d,%ld,%d)\n",fd,off,type);
420 /* not compressed? just use normal _llseek() */
421 if (!(lzs = GET_LZ_STATE(fd))) return _llseek(fd,off,type);
422 newwanted = lzs->realwanted;
424 case 1: /* SEEK_CUR */
427 case 2: /* SEEK_END */
428 newwanted = lzs->reallength-off;
430 default:/* SEEK_SET */
434 if (newwanted>lzs->reallength)
435 return LZERROR_BADVALUE;
437 return LZERROR_BADVALUE;
438 lzs->realwanted = newwanted;
443 /***********************************************************************
444 * LZCopy (KERNEL32.@)
446 * Copies everything from src to dest
447 * if src is a LZ compressed file, it will be uncompressed.
448 * will return the number of bytes written to dest or errors.
450 LONG WINAPI LZCopy( HFILE src, HFILE dest )
452 int usedlzinit = 0, ret, wret;
454 HFILE oldsrc = src, srcfd;
459 /* we need that weird typedef, for i can't seem to get function pointer
460 * casts right. (Or they probably just do not like WINAPI in general)
462 typedef UINT (WINAPI *_readfun)(HFILE,LPVOID,UINT);
466 TRACE("(%d,%d)\n",src,dest);
467 if (!IS_LZ_HANDLE(src)) {
469 if ((INT)src <= 0) return 0;
470 if (src != oldsrc) usedlzinit=1;
473 /* not compressed? just copy */
474 if (!IS_LZ_HANDLE(src))
477 xread=(_readfun)LZRead;
480 ret=xread(src,buf,BUFLEN);
489 wret = _lwrite(dest,buf,ret);
491 return LZERROR_WRITE;
494 /* Maintain the timestamp of source file to destination file */
495 srcfd = (!(lzs = GET_LZ_STATE(src))) ? src : lzs->realfd;
496 GetFileTime((HANDLE)srcfd, NULL, NULL, &filetime);
497 SetFileTime((HANDLE)dest, NULL, NULL, &filetime);
506 /* reverses GetExpandedPathname */
507 static LPSTR LZEXPAND_MangleName( LPCSTR fn )
510 char *mfn = HeapAlloc( GetProcessHeap(), 0, strlen(fn) + 3 ); /* "._" and \0 */
511 if(mfn == NULL) return NULL;
513 if (!(p = strrchr( mfn, '\\' ))) p = mfn;
514 if ((p = strchr( p, '.' )))
517 if (strlen(p) < 3) strcat( p, "_" ); /* append '_' */
518 else p[strlen(p)-1] = '_'; /* replace last character */
520 else strcat( mfn, "._" ); /* append "._" */
525 /***********************************************************************
526 * LZOpenFileA (KERNEL32.@)
528 * Opens a file. If not compressed, open it as a normal file.
530 HFILE WINAPI LZOpenFileA( LPSTR fn, LPOFSTRUCT ofs, WORD mode )
534 TRACE("(%s,%p,%d)\n",fn,ofs,mode);
535 /* 0x70 represents all OF_SHARE_* flags, ignore them for the check */
536 fd=OpenFile(fn,ofs,mode);
539 LPSTR mfn = LZEXPAND_MangleName(fn);
540 fd = OpenFile(mfn,ofs,mode);
541 HeapFree( GetProcessHeap(), 0, mfn );
543 if ((mode&~0x70)!=OF_READ)
548 if ((INT)cfd <= 0) return fd;
553 /***********************************************************************
554 * LZOpenFileW (KERNEL32.@)
556 HFILE WINAPI LZOpenFileW( LPWSTR fn, LPOFSTRUCT ofs, WORD mode )
559 DWORD len = WideCharToMultiByte( CP_ACP, 0, fn, -1, NULL, 0, NULL, NULL );
560 LPSTR xfn = HeapAlloc( GetProcessHeap(), 0, len );
561 WideCharToMultiByte( CP_ACP, 0, fn, -1, xfn, len, NULL, NULL );
562 ret = LZOpenFileA(xfn,ofs,mode);
563 HeapFree( GetProcessHeap(), 0, xfn );
568 /***********************************************************************
569 * LZClose (KERNEL32.@)
571 void WINAPI LZClose( HFILE fd )
576 if (!(lzs = GET_LZ_STATE(fd))) _lclose(fd);
579 HeapFree( GetProcessHeap(), 0, lzs->get );
580 CloseHandle((HANDLE)lzs->realfd);
581 lzstates[fd - 0x400] = NULL;
582 HeapFree( GetProcessHeap(), 0, lzs );
587 /***********************************************************************
588 * CopyLZFile (KERNEL32.@)
590 * Copy src to dest (including uncompressing src).
591 * NOTE: Yes. This is exactly the same function as LZCopy.
593 LONG WINAPI CopyLZFile( HFILE src, HFILE dest )
595 TRACE("(%d,%d)\n",src,dest);
596 return LZCopy(src,dest);