lzexpand_main.c

winNT技术操作系统,国外开放的原代码和LIUX一样

        return LZERROR_BADVALUE;
    }
    WideCharToMultiByte( CP_ACP, 0, in, -1, xin, len, NULL, NULL );
    if ((ret = GetExpandedNameA( xin, xout )) > 0)
        MultiByteToWideChar( CP_ACP, 0, xout, -1, out, wcslen(in)+4 );
    RtlFreeHeap( RtlGetProcessHeap(), 0, xin );
    RtlFreeHeap( RtlGetProcessHeap(), 0, xout );
    return ret;
}


/***********************************************************************
 *           LZRead   (LZ32.@)
 *
 * @implemented
 */
INT WINAPI LZRead( HFILE fd, LPSTR vbuf, INT toread )
{
	int	howmuch;
	BYTE	b,*buf;
	struct	lzstate	*lzs;

	buf=(LPBYTE)vbuf;
	DPRINT("(%d,%p,%d)\n",fd,buf,toread);
	howmuch=toread;
	if (!(lzs = GET_LZ_STATE(fd))) return _hread(fd,buf,toread);

/* 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   (LZ32.@)
 *
 * @implemented
 */
LONG WINAPI LZSeek( HFILE fd, LONG off, INT type )
{
	struct	lzstate	*lzs;
	LONG	newwanted;

	DPRINT("(%d,%ld,%d)\n",fd,off,type);
	/* not compressed? just use normal _llseek() */
        if (!(lzs = GET_LZ_STATE(fd))) return _llseek(fd,off,type);
	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>(LONG)lzs->reallength)
		return LZERROR_BADVALUE;
	if (newwanted<0)
		return LZERROR_BADVALUE;
	lzs->realwanted	= newwanted;
	return newwanted;
}


/***********************************************************************
 *           LZCopy   (LZ32.@)
 *
 * 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.
 *
 * @implemented
 */
LONG WINAPI LZCopy( HFILE src, HFILE dest )
{
	int	usedlzinit=0,ret,wret;
	LONG	len;
 	HFILE	oldsrc = src, srcfd;
 	FILETIME filetime;
 	struct	lzstate	*lzs;

#define BUFLEN	1000
	CHAR	buf[BUFLEN];
	/* we need that weird typedef, for i can't seem to get function pointer
	 * casts right. (Or they probably just do not like WINAPI in general)
	 */
	typedef	UINT	(WINAPI *_readfun)(HFILE,LPVOID,UINT);

	_readfun	xread;

	DPRINT("(%d,%d)\n",src,dest);
	if (!IS_LZ_HANDLE(src)) {
		src = LZInit(src);
                if ((INT)src <= 0) return 0;
		if (src != oldsrc) usedlzinit=1;
	}

	/* not compressed? just copy */
        if (!IS_LZ_HANDLE(src))
		xread=(_readfun)_hread;
	else
		xread=(_readfun)LZRead;
	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	= _hwrite(dest,buf,ret);
		if (wret!=ret)
			return LZERROR_WRITE;
	}

 	/* Maintain the timestamp of source file to destination file */
 	srcfd = (!(lzs = GET_LZ_STATE(src))) ? src : lzs->realfd;
 	GetFileTime((HANDLE)srcfd, NULL, NULL, &filetime);
 	SetFileTime((HANDLE)dest, NULL, NULL, &filetime);

 	/* close handle */
	if (usedlzinit)
		LZClose(src);
	return len;
#undef BUFLEN
}

/* reverses GetExpandedPathname */
static LPSTR LZEXPAND_MangleName( LPCSTR fn )
{
    char *p;
    char *mfn = (char *)RtlAllocateHeap( GetProcessHeap(), 0,
                                   strlen(fn) + 3 ); /* "._" and \0 */
    if(mfn == NULL) return NULL;
    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;
}

/***********************************************************************
 *           LZOpenFileA   (LZ32.@)
 *
 * Opens a file. If not compressed, open it as a normal file.
 *
 * @implemented
 */
HFILE WINAPI LZOpenFileA( LPSTR fn, LPOFSTRUCT ofs, WORD mode )
{
	HFILE	fd,cfd;

	DPRINT("(%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);
            RtlFreeHeap( GetProcessHeap(), 0, mfn );
	}
	if ((mode&~0x70)!=OF_READ)
		return fd;
	if (fd==HFILE_ERROR)
		return HFILE_ERROR;
	cfd=LZInit(fd);
	if ((INT)cfd <= 0) return fd;
	return cfd;
}


/***********************************************************************
 *           LZOpenFileW   (LZ32.@)
 *
 * @implemented
 */
HFILE WINAPI LZOpenFileW( LPWSTR fn, LPOFSTRUCT ofs, WORD mode )
{
    HFILE ret;
    DWORD len = WideCharToMultiByte( CP_ACP, 0, fn, -1, NULL, 0, NULL, NULL );
    LPSTR xfn = RtlAllocateHeap( GetProcessHeap(), 0, len );
    WideCharToMultiByte( CP_ACP, 0, fn, -1, xfn, len, NULL, NULL );
    ret = LZOpenFileA(xfn,ofs,mode);
    RtlFreeHeap( GetProcessHeap(), 0, xfn );
    return ret;
}


/***********************************************************************
 *           LZClose   (LZ32.@)
 *
 * @implemented
 */
void WINAPI LZClose( HFILE fd )
{
	struct lzstate *lzs;

	DPRINT("(%d)\n",fd);
        if (!(lzs = GET_LZ_STATE(fd))) _lclose(fd);
        else
        {
            if (lzs->get) RtlFreeHeap( GetProcessHeap(), 0, lzs->get );
            CloseHandle((HANDLE)lzs->realfd);
            lzstates[fd - 0x400] = NULL;
            RtlFreeHeap( GetProcessHeap(), 0, lzs );
        }
}


/***********************************************************************
 *           CopyLZFile  (LZ32.@)
 *
 * Copy src to dest (including uncompressing src).
 * NOTE: Yes. This is exactly the same function as LZCopy.
 *
 * @implemented
 */
LONG WINAPI CopyLZFile( HFILE src, HFILE dest )
{
    DPRINT("(%d,%d)\n",src,dest);
    return LZCopy(src,dest);
}