unzip.cpp

不需要额外的库

	x += ((uLong)i)<<24;

	if (err==UNZ_OK)
	*pX = x;
	else
	*pX = 0;
	return err;
	*/
}


/* My own strcmpi / strcasecmp */
static int strcmpcasenosensitive_internal (const char* fileName1,const char* fileName2)
{
	for (;;)
	{
		char c1=*(fileName1++);
		char c2=*(fileName2++);
		if ((c1>='a') && (c1<='z'))
			c1 -= 0x20;
		if ((c2>='a') && (c2<='z'))
			c2 -= 0x20;
		if (c1=='\0')
			return ((c2=='\0') ? 0 : -1);
		if (c2=='\0')
			return 1;
		if (c1<c2)
			return -1;
		if (c1>c2)
			return 1;
	}
}


#ifdef  CASESENSITIVITYDEFAULT_NO
#define CASESENSITIVITYDEFAULTVALUE 2
#else
#define CASESENSITIVITYDEFAULTVALUE 1
#endif

#ifndef STRCMPCASENOSENTIVEFUNCTION
#define STRCMPCASENOSENTIVEFUNCTION strcmpcasenosensitive_internal
#endif

/* 
Compare two filename (fileName1,fileName2).
If iCaseSenisivity = 1, comparision is case sensitivity (like strcmp)
If iCaseSenisivity = 2, comparision is not case sensitivity (like strcmpi
or strcasecmp)
If iCaseSenisivity = 0, case sensitivity is defaut of your operating system
(like 1 on Unix, 2 on Windows)

*/
extern  int unzStringFileNameCompare (const char* fileName1,const char* fileName2,int iCaseSensitivity)
{
	if (iCaseSensitivity==0)
		iCaseSensitivity=CASESENSITIVITYDEFAULTVALUE;

	if (iCaseSensitivity==1)
		return strcmp(fileName1,fileName2);

	return STRCMPCASENOSENTIVEFUNCTION(fileName1,fileName2);
} 

#define BUFREADCOMMENT (0x400)

/*
Locate the Central directory of a zipfile (at the end, just before
the global comment)
*/
extern uLong unzlocal_SearchCentralDir(FILE *fin)
{
	unsigned char* buf;
	uLong uSizeFile;
	uLong uBackRead;
	uLong uMaxBack=0xffff; /* maximum size of global comment */
	uLong uPosFound=0;

	if (fseek(fin,0,SEEK_END) != 0)
		return 0;


	uSizeFile = ftell( fin );

	if (uMaxBack>uSizeFile)
		uMaxBack = uSizeFile;

	buf = (unsigned char*)ALLOC(BUFREADCOMMENT+4);
	if (buf==NULL)
		return 0;

	uBackRead = 4;
	while (uBackRead<uMaxBack)
	{
		uLong uReadSize,uReadPos ;
		int i;
		if (uBackRead+BUFREADCOMMENT>uMaxBack) 
			uBackRead = uMaxBack;
		else
			uBackRead+=BUFREADCOMMENT;
		uReadPos = uSizeFile-uBackRead ;

		uReadSize = ((BUFREADCOMMENT+4) < (uSizeFile-uReadPos)) ? 
			(BUFREADCOMMENT+4) : (uSizeFile-uReadPos);
		if (fseek(fin,uReadPos,SEEK_SET)!=0)
			break;

		if (fread(buf,(uInt)uReadSize,1,fin)!=1)
			break;

		for (i=(int)uReadSize-3; (i--)>0;)
			if (((*(buf+i))==0x50) && ((*(buf+i+1))==0x4b) && 
				((*(buf+i+2))==0x05) && ((*(buf+i+3))==0x06))
			{
				uPosFound = uReadPos+i;
				break;
			}

			if (uPosFound!=0)
				break;
	}
	TRYFREE(buf);
	return uPosFound;
}

extern unzFile unzReOpen (const char* path, unzFile file)
{
	unz_s *s;
	FILE * fin;

	fin=fopen(path,"rb");
	if (fin==NULL)
		return NULL;

	s=(unz_s*)ALLOC(sizeof(unz_s));
	memcpy(s, (unz_s*)file, sizeof(unz_s));

	s->file = fin;
	return (unzFile)s;	
}

/*
Open a Zip file. path contain the full pathname (by example,
on a Windows NT computer "c:\\test\\zlib109.zip" or on an Unix computer
"zlib/zlib109.zip".
If the zipfile cannot be opened (file don't exist or in not valid), the
return value is NULL.
Else, the return value is a unzFile Handle, usable with other function
of this unzip package.
*/
extern unzFile unzOpen (const char* path)
{
	unz_s us;
	unz_s *s;
	uLong central_pos,uL;
	FILE * fin ;

	uLong number_disk;          /* number of the current dist, used for 
								spaning ZIP, unsupported, always 0*/
	uLong number_disk_with_CD;  /* number the the disk with central dir, used
								for spaning ZIP, unsupported, always 0*/
	uLong number_entry_CD;      /* total number of entries in
								the central dir 
								(same than number_entry on nospan) */

	int err=UNZ_OK;

	fin=fopen(path,"rb");
	if (fin==NULL)
		return NULL;

	central_pos = unzlocal_SearchCentralDir(fin);
	if (central_pos==0)
		err=UNZ_ERRNO;

	if (fseek(fin,central_pos,SEEK_SET)!=0)
		err=UNZ_ERRNO;

	/* the signature, already checked */
	if (unzlocal_getLong(fin,&uL)!=UNZ_OK)
		err=UNZ_ERRNO;

	/* number of this disk */
	if (unzlocal_getShort(fin,&number_disk)!=UNZ_OK)
		err=UNZ_ERRNO;

	/* number of the disk with the start of the central directory */
	if (unzlocal_getShort(fin,&number_disk_with_CD)!=UNZ_OK)
		err=UNZ_ERRNO;

	/* total number of entries in the central dir on this disk */
	if (unzlocal_getShort(fin,&us.gi.number_entry)!=UNZ_OK)
		err=UNZ_ERRNO;

	/* total number of entries in the central dir */
	if (unzlocal_getShort(fin,&number_entry_CD)!=UNZ_OK)
		err=UNZ_ERRNO;

	if ((number_entry_CD!=us.gi.number_entry) ||
		(number_disk_with_CD!=0) ||
		(number_disk!=0))
		err=UNZ_BADZIPFILE;

	/* size of the central directory */
	if (unzlocal_getLong(fin,&us.size_central_dir)!=UNZ_OK)
		err=UNZ_ERRNO;

	/* offset of start of central directory with respect to the 
	starting disk number */
	if (unzlocal_getLong(fin,&us.offset_central_dir)!=UNZ_OK)
		err=UNZ_ERRNO;

	/* zipfile comment length */
	if (unzlocal_getShort(fin,&us.gi.size_comment)!=UNZ_OK)
		err=UNZ_ERRNO;

	if ((central_pos<us.offset_central_dir+us.size_central_dir) && 
		(err==UNZ_OK))
		err=UNZ_BADZIPFILE;

	if (err!=UNZ_OK)
	{
		fclose(fin);
		return NULL;
	}

	us.file=fin;
	us.byte_before_the_zipfile = central_pos -
		(us.offset_central_dir+us.size_central_dir);
	us.central_pos = central_pos;
	us.pfile_in_zip_read = NULL;


	s=(unz_s*)ALLOC(sizeof(unz_s));
	*s=us;
	//	unzGoToFirstFile((unzFile)s);	
	return (unzFile)s;	
}


/*
Close a ZipFile opened with unzipOpen.
If there is files inside the .Zip opened with unzipOpenCurrentFile (see later),
these files MUST be closed with unzipCloseCurrentFile before call unzipClose.
return UNZ_OK if there is no problem. */
extern int unzClose (unzFile file)
{
	unz_s* s;
	if (file==NULL)
		return UNZ_PARAMERROR;
	s=(unz_s*)file;

	if (s->pfile_in_zip_read!=NULL)
		unzCloseCurrentFile(file);

	fclose(s->file);
	TRYFREE(s);
	return UNZ_OK;
}


/*
Write info about the ZipFile in the *pglobal_info structure.
No preparation of the structure is needed
return UNZ_OK if there is no problem. */
extern int unzGetGlobalInfo (unzFile file,unz_global_info *pglobal_info)
{
	unz_s* s;
	if (file==NULL)
		return UNZ_PARAMERROR;
	s=(unz_s*)file;
	*pglobal_info=s->gi;
	return UNZ_OK;
}


/*
Translate date/time from Dos format to tm_unz (readable more easilty)
*/
static void unzlocal_DosDateToTmuDate (uLong ulDosDate, tm_unz* ptm)
{
	uLong uDate;
	uDate = (uLong)(ulDosDate>>16);
	ptm->tm_mday = (uInt)(uDate&0x1f) ;
	ptm->tm_mon =  (uInt)((((uDate)&0x1E0)/0x20)-1) ;
	ptm->tm_year = (uInt)(((uDate&0x0FE00)/0x0200)+1980) ;

	ptm->tm_hour = (uInt) ((ulDosDate &0xF800)/0x800);
	ptm->tm_min =  (uInt) ((ulDosDate&0x7E0)/0x20) ;
	ptm->tm_sec =  (uInt) (2*(ulDosDate&0x1f)) ;
}

/*
Get Info about the current file in the zipfile, with internal only info
*/
static int unzlocal_GetCurrentFileInfoInternal (unzFile file,
												unz_file_info *pfile_info,
												unz_file_info_internal 
												*pfile_info_internal,
												char *szFileName,
												uLong fileNameBufferSize,
												void *extraField,
												uLong extraFieldBufferSize,
												char *szComment,
												uLong commentBufferSize)
{
	unz_s* s;
	unz_file_info file_info;
	unz_file_info_internal file_info_internal;
	int err=UNZ_OK;
	uLong uMagic;
	long lSeek=0;

	if (file==NULL)
		return UNZ_PARAMERROR;
	s=(unz_s*)file;
	if (fseek(s->file,s->pos_in_central_dir+s->byte_before_the_zipfile,SEEK_SET)!=0)
		err=UNZ_ERRNO;


	/* we check the magic */
	if (err==UNZ_OK) {
		if (unzlocal_getLong(s->file,&uMagic) != UNZ_OK)
			err=UNZ_ERRNO;
		else if (uMagic!=0x02014b50)
			err=UNZ_BADZIPFILE;
	}
	if (unzlocal_getShort(s->file,&file_info.version) != UNZ_OK)
		err=UNZ_ERRNO;

	if (unzlocal_getShort(s->file,&file_info.version_needed) != UNZ_OK)
		err=UNZ_ERRNO;

	if (unzlocal_getShort(s->file,&file_info.flag) != UNZ_OK)
		err=UNZ_ERRNO;

	if (unzlocal_getShort(s->file,&file_info.compression_method) != UNZ_OK)
		err=UNZ_ERRNO;

	if (unzlocal_getLong(s->file,&file_info.dosDate) != UNZ_OK)
		err=UNZ_ERRNO;

	unzlocal_DosDateToTmuDate(file_info.dosDate,&file_info.tmu_date);

	if (unzlocal_getLong(s->file,&file_info.crc) != UNZ_OK)
		err=UNZ_ERRNO;

	if (unzlocal_getLong(s->file,&file_info.compressed_size) != UNZ_OK)
		err=UNZ_ERRNO;

	if (unzlocal_getLong(s->file,&file_info.uncompressed_size) != UNZ_OK)
		err=UNZ_ERRNO;

	if (unzlocal_getShort(s->file,&file_info.size_filename) != UNZ_OK)
		err=UNZ_ERRNO;

	if (unzlocal_getShort(s->file,&file_info.size_file_extra) != UNZ_OK)
		err=UNZ_ERRNO;

	if (unzlocal_getShort(s->file,&file_info.size_file_comment) != UNZ_OK)
		err=UNZ_ERRNO;

	if (unzlocal_getShort(s->file,&file_info.disk_num_start) != UNZ_OK)
		err=UNZ_ERRNO;

	if (unzlocal_getShort(s->file,&file_info.internal_fa) != UNZ_OK)
		err=UNZ_ERRNO;

	if (unzlocal_getLong(s->file,&file_info.external_fa) != UNZ_OK)
		err=UNZ_ERRNO;

	if (unzlocal_getLong(s->file,&file_info_internal.offset_curfile) != UNZ_OK)
		err=UNZ_ERRNO;

	lSeek+=file_info.size_filename;
	if ((err==UNZ_OK) && (szFileName!=NULL))
	{
		uLong uSizeRead ;
		if (file_info.size_filename<fileNameBufferSize)
		{
			*(szFileName+file_info.size_filename)='\0';
			uSizeRead = file_info.size_filename;
		}
		else
			uSizeRead = fileNameBufferSize;

		if ((file_info.size_filename>0) && (fileNameBufferSize>0))
			if (fread(szFileName,(uInt)uSizeRead,1,s->file)!=1)