Sweden-Number/misc/lzexpand.c

579 lines
13 KiB
C

/*
* LZ Decompression functions
*
* Copyright 1996 Marcus Meissner
*/
/*
* FIXME: return values might be wrong
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <ctype.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "windows.h"
#include "file.h"
#include "lzexpand.h"
#include "stackframe.h"
#include "stddebug.h"
#include "debug.h"
#include "xmalloc.h"
#include "string32.h"
#define strdupW2A(x) STRING32_DupUniToAnsi(x)
#define strdupA2W(x) STRING32_DupAnsiToUni(x)
#define strcpyAW(a,b) STRING32_AnsiToUni(a,b)
/* The readahead length of the decompressor. Reading single bytes
* using _lread() would be SLOW.
*/
#define GETLEN 2048
/* Format of first 14 byte of LZ compressed file */
struct lzfileheader {
BYTE magic[8];
BYTE compressiontype;
CHAR lastchar;
DWORD reallength;
};
static BYTE LZMagic[8]={'S','Z','D','D',0x88,0xf0,0x27,0x33};
static struct lzstate {
HFILE lzfd; /* the handle used by the program */
HFILE realfd; /* the real filedescriptor */
CHAR lastchar; /* the last char of the filename */
DWORD reallength; /* the decompressed length of the file */
DWORD realcurrent; /* the position the decompressor currently is */
DWORD realwanted; /* the position the user wants to read from */
BYTE table[0x1000]; /* the rotating LZ table */
UINT curtabent; /* CURrent TABle ENTry */
BYTE stringlen; /* length and position of current string */
DWORD stringpos; /* from stringtable */
WORD bytetype; /* bitmask within blocks */
BYTE *get; /* GETLEN bytes */
DWORD getcur; /* current read */
DWORD getlen; /* length last got */
} *lzstates=NULL;
static int nroflzstates=0;
/* reads one compressed byte, including buffering */
#define GET(lzs,b) _lzget(lzs,&b)
#define GET_FLUSH(lzs) lzs->getcur=lzs->getlen;
static int
_lzget(struct lzstate *lzs,BYTE *b) {
if (lzs->getcur<lzs->getlen) {
*b = lzs->get[lzs->getcur++];
return 1;
} else {
int ret = FILE_Read(lzs->realfd,lzs->get,GETLEN);
if (ret==HFILE_ERROR)
return HFILE_ERROR;
if (ret==0)
return 0;
lzs->getlen = ret;
lzs->getcur = 1;
*b = *(lzs->get);
return 1;
}
}
/* internal function, reads lzheader
* returns BADINHANDLE for non filedescriptors
* return 0 for file not compressed using LZ
* return UNKNOWNALG for unknown algorithm
* returns lzfileheader in *head
*/
static INT
read_header(HFILE fd,struct lzfileheader *head) {
BYTE buf[14];
if (_llseek(fd,0,SEEK_SET)==-1)
return LZERROR_BADINHANDLE;
/* We can't directly read the lzfileheader struct due to
* structure element alignment
*/
if (FILE_Read(fd,buf,14)<14)
return 0;
memcpy(head->magic,buf,8);
memcpy(&(head->compressiontype),buf+8,1);
memcpy(&(head->lastchar),buf+9,1);
/* FIXME: consider endianess on non-intel architectures */
memcpy(&(head->reallength),buf+10,4);
if (memcmp(head->magic,LZMagic,8))
return 0;
if (head->compressiontype!='A')
return LZERROR_UNKNOWNALG;
return 1;
}
/*
* LZStart [LZEXPAND.7] [LZ32.6]
*/
INT16 LZStart(void)
{
dprintf_file(stddeb,"LZStart(void)\n");
return 1;
}
/*
* LZInit [LZEXPAND.3] [LZ32.2]
*
* initializes internal decompression buffers, returns lzfiledescriptor.
* (return value the same as hfSrc, if hfSrc is not compressed)
* on failure, returns error code <0
* lzfiledescriptors range from 0x400 to 0x410 (only 16 open files per process)
* we use as much as we need, we just OR 0x400 to the passed HFILE.
*
* since _llseek uses the same types as libc.lseek, we just use the macros of
* libc
*/
HFILE
LZInit(HFILE hfSrc) {
struct lzfileheader head;
struct lzstate *lzs;
DWORD ret;
dprintf_file(stddeb,"LZInit(%d)\n",hfSrc);
ret=read_header(hfSrc,&head);
if (ret<=0) {
_llseek(hfSrc,0,SEEK_SET);
return ret?ret:hfSrc;
}
lzstates=xrealloc(lzstates,(++nroflzstates)*sizeof(struct lzstate));
lzs = lzstates+(nroflzstates-1);
memset(lzs,'\0',sizeof(*lzs));
lzs->realfd = hfSrc;
lzs->lzfd = hfSrc | 0x400;
lzs->lastchar = head.lastchar;
lzs->reallength = head.reallength;
lzs->get = xmalloc(GETLEN);
lzs->getlen = 0;
lzs->getcur = 0;
/* Yes, preinitialize with spaces */
memset(lzs->table,' ',0x1000);
/* Yes, start 16 byte from the END of the table */
lzs->curtabent = 0xff0;
return lzs->lzfd;
}
/*
* LZDone [LZEXPAND.9] [LZ32.8]
*/
void
LZDone(void) {
dprintf_file(stddeb,"LZDone()\n");
}
/*
* GetExpandedName [LZEXPAND.10]
*
* gets the full filename of the compressed file 'in' by opening it
* and reading the header
*
* "file." is being translated to "file"
* "file.bl_" (with lastchar 'a') is being translated to "file.bla"
* "FILE.BL_" (with lastchar 'a') is being translated to "FILE.BLA"
*/
INT16
GetExpandedName16(LPCSTR in,LPSTR out) {
struct lzfileheader head;
HFILE fd;
OFSTRUCT ofs;
INT fnislowercased,ret,len;
LPSTR s,t;
dprintf_file(stddeb,"GetExpandedName(%s)\n",in);
fd=OpenFile(in,&ofs,OF_READ);
if (fd==HFILE_ERROR)
return LZERROR_BADINHANDLE;
ret=read_header(fd,&head);
if (ret<=0) {
_lclose(fd);
return LZERROR_BADINHANDLE;
}
/* This line will crash if the caller hasn't allocated enough memory
* for us.
*/
strcpy(out,in);
/* look for directory prefix and skip it. */
s=out;
while (NULL!=(t=strpbrk(s,"/\\:")))
s=t+1;
/* now mangle the basename */
if (!*s) {
/* FIXME: hmm. shouldn't happen? */
fprintf(stddeb,__FILE__":GetExpandedFileName(), specified a directory or what? (%s)\n",in);
_lclose(fd);
return 1;
}
/* see if we should use lowercase or uppercase on the last char */
fnislowercased=1;
t=s+strlen(s)-1;
while (t>=out) {
if (!isalpha(*t)) {
t--;
continue;
}
fnislowercased=islower(*t);
break;
}
if (isalpha(head.lastchar)) {
if (fnislowercased)
head.lastchar=tolower(head.lastchar);
else
head.lastchar=toupper(head.lastchar);
}
/* now look where to replace the last character */
if (NULL!=(t=strchr(s,'.'))) {
if (t[1]=='\0') {
t[0]='\0';
} else {
len=strlen(t)-1;
if (t[len]=='_')
t[len]=head.lastchar;
}
} /* else no modification necessary */
_lclose(fd);
return 1;
}
/*
* GetExpandedNameW [LZ32.11]
*/
INT32
GetExpandedName32W(LPCWSTR in,LPWSTR out) {
char *xin,*xout;
INT32 ret;
xout = malloc(lstrlen32W(in)+3);
xin = strdupW2A(in);
ret = GetExpandedName16(xin,xout);
if (ret>0)
strcpyAW(out,xout);
free(xin);
free(xout);
return ret;
}
/*
* GetExpandedNameA [LZ32.9]
*/
INT32
GetExpandedName32A(LPCSTR in,LPSTR out) {
return GetExpandedName16(in,out);
}
/*
* LZRead [LZEXPAND.5] [LZ32.4]
* just as normal read, but reads from LZ special fd and uncompresses.
*/
INT16
LZRead16(HFILE fd,SEGPTR segbuf,UINT16 toread) {
dprintf_file(stddeb,"LZRead16(%d,%08lx,%d)\n",fd,(DWORD)segbuf,toread);
return LZRead32(fd,(LPBYTE)PTR_SEG_TO_LIN(segbuf),toread);
}
INT32
LZRead32(HFILE fd,LPVOID vbuf,UINT32 toread) {
int i,howmuch;
BYTE b,*buf;
struct lzstate *lzs;
buf=(LPBYTE)vbuf;
dprintf_file(stddeb,"LZRead32(%d,%p,%d)\n",fd,buf,toread);
howmuch=toread;
for (i=0;i<nroflzstates;i++)
if (lzstates[i].lzfd==fd)
break;
if (i==nroflzstates)
return FILE_Read(fd,buf,toread);
lzs=lzstates+i;
/* The decompressor itself is in a define, cause we need it twice
* in this function. (the decompressed byte will be in b)
*/
#define DECOMPRESS_ONE_BYTE \
if (lzs->stringlen) { \
b = lzs->table[lzs->stringpos]; \
lzs->stringpos = (lzs->stringpos+1)&0xFFF; \
lzs->stringlen--; \
} else { \
if (!(lzs->bytetype&0x100)) { \
if (1!=GET(lzs,b)) \
return toread-howmuch; \
lzs->bytetype = b|0xFF00; \
} \
if (lzs->bytetype & 1) { \
if (1!=GET(lzs,b)) \
return toread-howmuch; \
} else { \
BYTE b1,b2; \
\
if (1!=GET(lzs,b1)) \
return toread-howmuch; \
if (1!=GET(lzs,b2)) \
return toread-howmuch; \
/* Format: \
* b1 b2 \
* AB CD \
* where CAB is the stringoffset in the table\
* and D+3 is the len of the string \
*/ \
lzs->stringpos = b1|((b2&0xf0)<<4); \
lzs->stringlen = (b2&0xf)+2; \
/* 3, but we use a byte already below ... */\
b = lzs->table[lzs->stringpos];\
lzs->stringpos = (lzs->stringpos+1)&0xFFF;\
} \
lzs->bytetype>>=1; \
} \
/* store b in table */ \
lzs->table[lzs->curtabent++]= b; \
lzs->curtabent &= 0xFFF; \
lzs->realcurrent++;
/* if someone has seeked, we have to bring the decompressor
* to that position
*/
if (lzs->realcurrent!=lzs->realwanted) {
/* if the wanted position is before the current position
* I see no easy way to unroll ... We have to restart at
* the beginning. *sigh*
*/
if (lzs->realcurrent>lzs->realwanted) {
/* flush decompressor state */
_llseek(lzs->realfd,14,SEEK_SET);
GET_FLUSH(lzs);
lzs->realcurrent= 0;
lzs->bytetype = 0;
lzs->stringlen = 0;
memset(lzs->table,' ',0x1000);
lzs->curtabent = 0xFF0;
}
while (lzs->realcurrent<lzs->realwanted) {
DECOMPRESS_ONE_BYTE;
}
}
while (howmuch) {
DECOMPRESS_ONE_BYTE;
lzs->realwanted++;
*buf++ = b;
howmuch--;
}
return toread;
#undef DECOMPRESS_ONE_BYTE
}
/*
* LZSeek [LZEXPAND.4] [LZ32.3]
*
* works as the usual _llseek
*/
LONG
LZSeek(HFILE fd,LONG off,INT32 type) {
int i;
struct lzstate *lzs;
LONG newwanted;
dprintf_file(stddeb,"LZSeek(%d,%ld,%d)\n",fd,off,type);
for (i=0;i<nroflzstates;i++)
if (lzstates[i].lzfd==fd)
break;
/* not compressed? just use normal _llseek() */
if (i==nroflzstates)
return _llseek(fd,off,type);
lzs = lzstates+i;
newwanted = lzs->realwanted;
switch (type) {
case 1: /* SEEK_CUR */
newwanted += off;
break;
case 2: /* SEEK_END */
newwanted = lzs->reallength-off;
break;
default:/* SEEK_SET */
newwanted = off;
break;
}
if (newwanted>lzs->reallength)
return LZERROR_BADVALUE;
if (newwanted<0)
return LZERROR_BADVALUE;
lzs->realwanted = newwanted;
return newwanted;
}
/*
* LZCopy [LZEXPAND.1] [LZ32.0]
*
* Copies everything from src to dest
* if src is a LZ compressed file, it will be uncompressed.
* will return the number of bytes written to dest or errors.
*/
LONG
LZCopy(HFILE src,HFILE dest) {
int i,ret,wret;
LONG len;
#define BUFLEN 1000
BYTE buf[BUFLEN];
INT32 (*xread)(HFILE,LPVOID,UINT32);
dprintf_file(stddeb,"LZCopy(%d,%d)\n",src,dest);
for (i=0;i<nroflzstates;i++)
if (src==lzstates[i].lzfd)
break;
/* not compressed? just copy */
if (i==nroflzstates)
xread=FILE_Read;
else
xread=LZRead32;
len=0;
while (1) {
ret=xread(src,buf,BUFLEN);
if (ret<=0) {
if (ret==0)
break;
if (ret==-1)
return LZERROR_READ;
return ret;
}
len += ret;
wret = _lwrite(dest,buf,ret);
if (wret!=ret)
return LZERROR_WRITE;
}
return len;
#undef BUFLEN
}
/* reverses GetExpandedPathname */
static LPSTR LZEXPAND_MangleName( LPCSTR fn )
{
char *p;
char *mfn = (char *)xmalloc( strlen(fn) + 3 ); /* "._" and \0 */
strcpy( mfn, fn );
if (!(p = strrchr( mfn, '\\' ))) p = mfn;
if ((p = strchr( p, '.' )))
{
p++;
if (strlen(p) < 3) strcat( p, "_" ); /* append '_' */
else p[strlen(p)-1] = '_'; /* replace last character */
}
else strcat( mfn, "._" ); /* append "._" */
return mfn;
}
/*
* LZOpenFile [LZEXPAND.2]
* Opens a file. If not compressed, open it as a normal file.
*/
HFILE
LZOpenFile16(LPCSTR fn,LPOFSTRUCT ofs,UINT16 mode) {
HFILE fd,cfd;
dprintf_file(stddeb,"LZOpenFile(%s,%p,%d)\n",fn,ofs,mode);
/* 0x70 represents all OF_SHARE_* flags, ignore them for the check */
fd=OpenFile(fn,ofs,mode);
if (fd==HFILE_ERROR)
{
LPSTR mfn = LZEXPAND_MangleName(fn);
fd = OpenFile(mfn,ofs,mode);
free( mfn );
}
if ((mode&~0x70)!=OF_READ)
return fd;
if (fd==HFILE_ERROR)
return HFILE_ERROR;
cfd=LZInit(fd);
if (cfd<=0)
return fd;
return cfd;
}
/*
* LZOpenFileA [LZ32.1]
*/
HFILE
LZOpenFile32A(LPCSTR fn,LPOFSTRUCT ofs,UINT32 mode) {
return LZOpenFile16(fn,ofs,mode);
}
/*
* LZOpenFileW [LZ32.10]
*/
HFILE
LZOpenFile32W(LPCWSTR fn,LPOFSTRUCT ofs,UINT32 mode) {
LPSTR xfn;
LPWSTR yfn;
HFILE ret;
xfn = strdupW2A(fn);
ret = LZOpenFile16(xfn,ofs,mode);
free(xfn);
if (ret!=HFILE_ERROR) {
/* ofs->szPathName is an array with the OFSTRUCT */
yfn = strdupA2W(ofs->szPathName);
memcpy(ofs->szPathName,yfn,lstrlen32W(yfn)*2+2);
free(yfn);
}
return ret;
}
/*
* LZClose [LZEXPAND.6] [LZ32.5]
*/
void
LZClose(HFILE fd) {
int i;
dprintf_file(stddeb,"LZClose(%d)\n",fd);
for (i=0;i<nroflzstates;i++)
if (lzstates[i].lzfd==fd)
break;
if (i==nroflzstates) {
_lclose(fd);
return;
}
if (lzstates[i].get)
free(lzstates[i].get);
_lclose(lzstates[i].realfd);
memcpy(lzstates+i,lzstates+i+1,sizeof(struct lzstate)*(nroflzstates-i-1));
nroflzstates--;
lzstates=xrealloc(lzstates,sizeof(struct lzstate)*nroflzstates);
}
/*
* CopyLZFile [LZEXPAND.8] [LZ32.7]
*
* Copy src to dest (including uncompressing src).
* NOTE: Yes. This is exactly the same function as LZCopy.
*/
LONG
CopyLZFile(HFILE src,HFILE dest) {
dprintf_file(stddeb,"CopyLZFile(%d,%d)\n",src,dest);
return LZCopy(src,dest);
}