ZIPAdv.bt

//------------------------------------------------
//--- 010 Editor v2.0 Binary Template
//
//      File: ZIPAdv.bt
//    Author: SweetScape Software
//   Version: 2.6
//   Purpose: Defines a template for
//            parsing ZIP files. Handles more
//            complex ZIP data such as ZIP64
//            that the base ZIP.bt cannot read.
//  Category: Archive
// File Mask: *.zip
//  ID Bytes: 50 4B //PK
//   History:  
//   2.6   2015-07-18  SweetScape: Updated header for repository submission.
//   2.5   G Woods:    Handle zero compressed size in header with ZIPDATADESCR header 
//                     after compressed data.
//   2.3   DCeres:     Added write function for VERECORD structure.
//                     Added write function for ZIP64ENDLOCATORRECORD structure.
//                     Added write function for ZIP64ENDLOCATOR structure.
//                     Added write function for EXTRAFIELD structure.
//   2.2   S.Gibson    Fix for entry comment field
//                     Fix for parsing data descriptors
//   2.1   SweetScape  Added write function for ZIPFILERECORD structure
//   2.0   SweetScape  Added read functions
//   1.0   SweetScape  Initial release
//
// More information available at:
//  https://en.wikipedia.org/wiki/Zip_%28file_format%29
//------------------------------------------------

// Define structures used in ZIP files

typedef enum <uint> {
	S_ZIPFILERECORD 		= 0x04034b50,
	S_ZIPDATADESCR 			= 0x08074b50,
	S_ZIPDIRENTRY 			= 0x02014b50, 
	S_ZIPDIGITALSIG 		= 0x05054b50,
	S_ZIP64ENDLOCATORRECORD = 0x06064b50,
	S_ZIP64ENDLOCATOR 		= 0x07064b50,
	S_ZIPENDLOCATOR 		= 0x06054b50
} SignatureTYPE <format=hex>;

typedef enum <byte> {
	OS_FAT      = 0,
	OS_AMIGA    = 1,
	OS_VMS      = 2,  // VAX/VMS
	OS_Unix     = 3,
	OS_VM_CMS   = 4,
	OS_Atari    = 5,  // what if it's a minix filesystem? [cjh]
	OS_HPFS     = 6,  // filesystem used by OS/2 (and NT 3.x)
	OS_Mac      = 7,
	OS_Z_System = 8,
	OS_CPM      = 9,
	OS_TOPS20   = 10, // pkzip 2.50 NTFS
	OS_NTFS     = 11, // filesystem used by Windows NT
	OS_QDOS     = 12, // SMS/QDOS
	OS_Acorn    = 13, // Archimedes Acorn RISC OS
	OS_VFAT     = 14, // filesystem used by Windows 95, NT
	OS_MVS      = 15,
	OS_BeOS     = 16, // hybrid POSIX/database filesystem
	OS_Tandem   = 17,
	OS_OS400    = 18,
	OS_OSX      = 19 
} HOSTOSTYPE;

typedef byte VERSIONTYPE <read=read_VERSIONTYPE>;

string read_VERSIONTYPE (local VERSIONTYPE &af) {
	local string s = "";  
	SPrintf (s, "%1.1f", (float)af / 10);  
	return s;
}

typedef struct{
	VERSIONTYPE Version;
	HOSTOSTYPE HostOS;
} VERECORD <read=read_VERECORD>;

string read_VERECORD (local VERECORD &af) {
	local string s = "";  
	SPrintf (s, "Ver %1.1f, ", (float)af.Version / 10);  
	s +=  EnumToString(  af.HostOS);
	return s;
}

//enum used for compression format
typedef enum <short> { 
	COMP_STORED    		= 0,
	COMP_SHRUNK    		= 1,
	COMP_REDUCED1  		= 2,
	COMP_REDUCED2  		= 3,
	COMP_REDUCED3  		= 4,
	COMP_REDUCED4  		= 5,
	COMP_IMPLODED  		= 6,
	COMP_TOKEN     		= 7,
	COMP_DEFLATE   		= 8, // Deflate - standard ZIP codec, used from the start, also found in regular ZIP files
	COMP_DEFLATE64 		= 9,
	COMP_PKImploding 	= 10,
	
	COMP_BZip2			= 12, // BZIP2 - Newer than deflate, with better compression and slightly slower speed.
	COMP_LZMA 			= 14, // LZMA - advanced ZIPX codec, taken from open source 7-zip format
	COMP_Terse 			= 18,
	COMP_Lz77 			= 19,
	
	COMP_Jpeg 			= 0x60, // Jpeg - Codec added by WinZip for specific support of jpeg images ( http://www.winzip.com/wz_jpg_comp.pdf )
	COMP_WavPack		= 0x61, // WavPack - Codec for compressing specifically wav files. ( http://www.wavpack.com )
	COMP_PPMd 			= 0x62, // PPMd - context modeling based codec, also featured in new ZIP standard. We use it in our Optimized method for text file compression. ( http://www.compression.ru/ds/ )
	COMP_WzAES 			= 0x63  // WZAES encryption methods
} COMPTYPE;

typedef enum <ushort>{ 
	FLAG_Encrypted             = 0x0001, //Bit 0: If set, indicates that the file is encrypted.
	FLAG_CompressionFlagBit1   = 0x0002, 
	FLAG_CompressionFlagBit2   = 0x0004,
	FLAG_DescriptorUsedMask    = 0x0008,
	FLAG_Reserved1             = 0x0010,
	FLAG_Reserved2             = 0x0020,
	FLAG_StrongEncrypted       = 0x0040, //Bit 6: Strong encryption
	FLAG_CurrentlyUnused1      = 0x0080,
	FLAG_CurrentlyUnused2      = 0x0100,
	FLAG_CurrentlyUnused3      = 0x0200,
	FLAG_CurrentlyUnused4      = 0x0400,
	FLAG_Utf8                  = 0x0800, // Bit 11: filename and comment encoded using UTF-8
	FLAG_ReservedPKWARE1       = 0x1000,
	FLAG_CDEncrypted           = 0x2000, // Bit 13: Used when encrypting the Central Directory to indicate selected data values in the Local Header are masked to hide their actual values.
	FLAG_ReservedPKWARE2       = 0x4000,
	FLAG_ReservedPKWARE3       = 0x8000,

} FLAGTYPE <read=read_FLAGTYPE>;

string read_FLAGTYPE (local FLAGTYPE &af) {
	local string s = "";
	local int commaNeeded = 0;
	local FLAGTYPE i = 1;

	SPrintf (s, "%d: ", af);  
	while (i < FLAG_ReservedPKWARE3) 
	{
		if (af & i)
		{
			if (commaNeeded) 
			{ s += ", "; }
			s +=  EnumToString(i);
			commaNeeded = 1;
		}
		i = i << 1;
	}
	return s;
}

typedef enum <ushort>{ 
	EH_Zip64 = 					0x0001,		//Zip64 extended information extra field
	EH_AVInfo = 				0x0007,		//AV Info
	EH_ExtLanguage = 			0x0008,		//Reserved for extended language encoding data (PFS)
	EH_OS2 = 					0x0009,		//OS/2
	EH_NTFS = 					0x000a,		//NTFS 
	EH_OpenVMS = 				0x000c,		//OpenVMS
	EH_UNIX = 					0x000d,		//UNIX
	EH_fileStream = 			0x000e,		//Reserved for file stream and fork descriptors
	EH_PatchDescriptor = 		0x000f,		//Patch Descriptor
	EH_PKCS7X509 = 				0x0014,		//PKCS#7 Store for X.509 Certificates
	EH_X509IDSignature = 		0x0015,		//X.509 Certificate ID and Signature for individual file
	EH_X509IDCD = 				0x0016,		//X.509 Certificate ID for Central Directory
	EH_StrongEncryption = 		0x0017,		//Strong Encryption Header
	EH_RecordManagement = 		0x0018,		//Record Management Controls
	EH_PKCS7List = 				0x0019,		//PKCS#7 Encryption Recipient Certificate List
	EH_Attributes = 			0x0065,		//IBM S/390 (Z390), AS/400 (I400) attributes uncompressed
	EH_ReservedAttributes = 	0x0066,		//Reserved for IBM S/390 (Z390), AS/400 (I400) attributes - compressed
	EH_POSZIP4690 = 			0x4690,		//POSZIP 4690 (reserved) 
	EH_Mac = 					0x07c8,		//Macintosh
	EH_ZipItMac1 = 				0x2605,		//ZipIt Macintosh
	EH_ZipItMac2 = 				0x2705,		//ZipIt Macintosh 1.3.5+
	EH_ZipItMac3 = 				0x2805,		//ZipIt Macintosh 1.3.5+
	EH_InfoZIPMac = 			0x334d,		//Info-ZIP Macintosh
	EH_Acorn = 					0x4341,		//Acorn/SparkFS 
	EH_WinNTSecurity = 			0x4453,		//Windows NT security descriptor (binary ACL)
	EH_VM_CMS = 				0x4704,		//VM/CMS
	EH_MVS = 					0x470f,		//MVS
	EH_FWKCS = 					0x4b46,		//FWKCS MD5 (see below)
	EH_OS2AccessList = 			0x4c41,		//OS/2 access control list (text ACL)
	EH_InfoZIPOpenVMS = 		0x4d49,		//Info-ZIP OpenVMS
	EH_Xceed = 					0x4f4c,		//Xceed original location extra field
	EH_AOSVS = 					0x5356,		//AOS/VS (ACL)
	EH_extTimestamp = 			0x5455,		//extended timestamp
	EH_XceedUnicode = 			0x554e,		//Xceed unicode extra field
	EH_InfoZIPUNIX = 			0x5855,		//Info-ZIP UNIX (original, also OS/2, NT, etc)
	EH_InfoZIPUnicodeComment = 	0x6375,		//Info-ZIP Unicode Comment Extra Field
	EH_BeOS = 					0x6542,		//BeOS/BeBox
	EH_InfoZIPUnicodePath = 	0x7075,		//Info-ZIP Unicode Path Extra Field
	EH_ASiUNIX = 				0x756e,		//ASi UNIX
	EH_InfoZIPUNIXNew = 		0x7855,		//Info-ZIP UNIX (16-bit UID/GID info)
	EH_InfoZIPUNIXNew3rd = 		0x7875,     //Info-ZIP UNIX 3rd generation (generic UID/GID, ...)
	EH_WinGrowth = 				0xa220,		//Microsoft Open Packaging Growth Hint
	EH_SMSQDOS = 				0xfd4a, 	//SMS/QDOS
    EH_WzAES                =   0x9901,      //
} HEADERFLAG;

typedef enum <ushort>{ 
    AlgID_DES       = 0x6601, //- DES
    AlgID_RC2OLD    = 0x6602, //- RC2 (version needed to extract < 5.2)
    AlgID_3DES168   = 0x6603, //- 3DES 168
    AlgID_3DES112   = 0x6609, //- 3DES 112
    AlgID_AES128    = 0x660E, //- AES 128 
    AlgID_AES192    = 0x660F, //- AES 192 
    AlgID_AES256    = 0x6610, //- AES 256 
    AlgID_RC2       = 0x6702, //- RC2 (version needed to extract >= 5.2)
    AlgID_Blowfish  = 0x6720, //- Blowfish
    AlgID_Twofish   = 0x6721, //- Twofish
    AlgID_RC4       = 0x6801, //- RC4
    AlgID_Unknown   = 0xFFFF, //- Unknown algorithm
} ALGFLAG;

typedef enum <byte>{ 
    AES128 = 0x01, 	//128-bit encryption key
    AES192 = 0x02, 	//192-bit encryption key
    AES256 = 0x03, 	//256-bit encryption key
} AESMODE;

typedef enum <ushort>{ 
    pfPassword  = 0x0001, //- Password is required to decrypt
    pfCertificates = 0x0002, //- Certificates only
    pfPasswordCertificates = 0x0003, //- Password or certificate required to decrypt
}   PRCFLAG;

typedef struct {
	HEADERFLAG  efHeaderID;
	ushort  efDataSize;

	Printf("%d", efHeaderID);
	switch (efHeaderID)
	{
	case EH_Zip64:
		uint64 efOriginalSize;
		uint64 efCompressedSize;
		//uint64 efHeaderOffset;
		//uint   efDiskNumberStart;
		break;
	case EH_InfoZIPUnicodePath:
		byte efVersion;
		uint efNameCRC32;
		if(efDataSize > 0 )
		    char efUnicodeName[efDataSize - 5];
		break;
    case EH_NTFS:
        int Reserved;   //4 bytes    Reserved for future use
	    local int len = efDataSize - 4;
	    while (len > 0)
        {
            ushort Tag;        //2 bytes    NTFS attribute tag value #1
            ushort Size;       //2 bytes    Size of attribute #1, in bytes
            if (Tag == 0x001)
            {
                FILETIME Mtime;      //8 bytes    File last modification time
                FILETIME Atime;      //8 bytes    File last access time
                FILETIME Ctime;     //8 bytes    File creation time                
            }
            else
                byte Data[Size]; //(var.)     Size1      Attribute #1 data
    		len -= Size + 4;
        }
        break;
    case EH_StrongEncryption:
        ushort  Format;    //2 bytes  Format definition for this record
        ALGFLAG AlgID;     //2 bytes  Encryption algorithm identifier
        ushort  Bitlen;    //2 bytes  Bit length of encryption key
        PRCFLAG Flags;     //2 bytes  Processing flags
        if (efDataSize > 8)
            byte    CertData[efDataSize - 8];  //TSize-8  Certificate decryption extra field data        
        break;
    case EH_WzAES:
        ushort version;         //2 bytes   Integer version number specific to the zip vendor
        char VendorID[2];       //2 bytes 	2-character vendor ID
        AESMODE Strength;       //1 bytes   Integer mode value indicating AES encryption strength
        COMPTYPE deCompression; //2 bytes The actual compression method used to compress the file
        break;
	default:
		if(efDataSize > 0 )
		    char efData[ efDataSize ];
        break;
	}
} EXTRAFIELD <read=read_EXTRAFIELD>;

string read_EXTRAFIELD (local EXTRAFIELD &af) 
{
	return EnumToString(af.efHeaderID);
}

typedef struct {
	HEADERFLAG  efHeaderID;
	uint  efDataSize;

	Printf("%d", efHeaderID);
	switch (efHeaderID)
	{
	case EH_Zip64:
		uint64 efOriginalSize;
		uint64 efCompressedSize;
		//uint64 efHeaderOffset;
		//uint   efDiskNumberStart;
		break;
	case EH_InfoZIPUnicodePath:
		byte efVersion;
		uint efNameCRC32;
		if(efDataSize > 0 )
		    char efUnicodeName[efDataSize - 5];
		break;
	default:
		if(efDataSize > 0 )
		    char efData[ efDataSize ];
        break;
	}
} EXTRA64FIELD;

typedef enum <uint>{
	FA_READONLY             = 0x00000001,  
	FA_HIDDEN               = 0x00000002,  
	FA_SYSTEM               = 0x00000004,  
	FA_DIRECTORY            = 0x00000010,  
	FA_ARCHIVE              = 0x00000020,  
	FA_DEVICE               = 0x00000040,  
	FA_NORMAL               = 0x00000080,  
	FA_TEMPORARY            = 0x00000100,  
	FA_SPARSE_FILE          = 0x00000200,  
	FA_REPARSE_POINT        = 0x00000400,  
	FA_COMPRESSED           = 0x00000800,  
	FA_OFFLINE              = 0x00001000,  
	FA_NOT_CONTENT_INDEXED  = 0x00002000,  
	FA_ENCRYPTED            = 0x00004000,  
	FA_VIRTUAL              = 0x00010000,  

    kIFMT   =   0170000 << 16,     /* Unix file type mask */
    
    kIFDIR  =   0040000 << 16,     /* Unix directory */
    kIFREG  =   0100000 << 16,     /* Unix regular file */
    kIFSOCK =   0140000 << 16,     /* Unix socket (BSD, not SysV or Amiga) */
    kIFLNK  =   0120000 << 16,     /* Unix symbolic link (not SysV, Amiga) */
    kIFBLK  =   0060000 << 16,     /* Unix block special       (not Amiga) */
    kIFCHR  =   0020000 << 16,     /* Unix character special   (not Amiga) */
    kIFIFO  =   0010000 << 16,     /* Unix fifo    (BCC, not MSC or Amiga) */
    
    kISUID  =   04000 << 16,       /* Unix set user id on execution */
    kISGID  =   02000 << 16,       /* Unix set group id on execution */
    kISVTX  =   01000 << 16,       /* Unix directory permissions control */
    kIRWXU  =   00700 << 16,       /* Unix read, write, execute: owner */
    kIRUSR  =   00400 << 16,       /* Unix read permission: owner */
    kIWUSR  =   00200 << 16,       /* Unix write permission: owner */
    kIXUSR  =   00100 << 16,       /* Unix execute permission: owner */
    kIRWXG  =   00070 << 16,       /* Unix read, write, execute: group */
    kIRGRP  =   00040 << 16,       /* Unix read permission: group */
    kIWGRP  =   00020 << 16,       /* Unix write permission: group */
    kIXGRP  =   00010 << 16,       /* Unix execute permission: group */
    kIRWXO  =   00007 << 16,       /* Unix read, write, execute: other */
    kIROTH  =   00004 << 16,       /* Unix read permission: other */
    kIWOTH  =   00002 << 16,       /* Unix write permission: other */
    kIXOTH  =   00001 << 16        /* Unix execute permission: other */
} FILEATTRIBUTE <read=read_FILEATTRIBUTE>;

string read_FILEATTRIBUTE (local FILEATTRIBUTE &af) {
	local string s = "";
	local int commaNeeded = 0;
	local FILEATTRIBUTE i = 1;

	SPrintf (s, "0x%X: ", af);  
	while (i < 	0xFFFFFF - 2) 
	{
		if (af & i)
		{
			if (commaNeeded) 
			{ 
                s += ", ";
            }
			s +=  EnumToString(i);
			commaNeeded = 1;
		}
		i = i << 1;
	}
	return s;
}

// Defintes the Data descriptor
typedef struct {
	SignatureTYPE ddSignature; //0x08074b50
	uint ddCRC <format=hex>;
	uint ddCompressedSize;
	uint ddUncompressedSize;
} ZIPDATADESCR;

// Defines a file record
typedef struct {
	// Header for the file
	SignatureTYPE frSignature;    //0x04034b50
	VERECORD frVersion;
	FLAGTYPE frFlags;
	COMPTYPE frCompression;
	DOSTIME  frFileTime;
	DOSDATE  frFileDate;
	uint     frCrc     <format=hex>;
	uint     frCompressedSize;
	uint     frUncompressedSize;
	ushort   frFileNameLength;
	ushort   frExtraFieldLength;
	if( frFileNameLength > 0 )
	char     frFileName[ frFileNameLength ];
	
	local int len = frExtraFieldLength;
	while (len > 0)
	{
		EXTRAFIELD frExtraField;
		len -= frExtraField.efDataSize + 4;
	}
	// Compressed data
	SetBackColor( cNone );

    if ((frFlags & FLAG_Encrypted) && ( frFlags & FLAG_StrongEncrypted))
    {
        struct
        {
            ushort  IVSize;
            byte    IVData[IVSize];
            uint    Size;
            ushort  Format;
            ALGFLAG AlgID;
            ushort  BitLen;
            ushort  Flags;
            ushort  ErdSize;
            byte    ErdData[ErdSize];
            uint    Reserved;
            ushort  VSize;
            byte    VData[VSize - 4];
            uint    VCRC32;
        } StrongEncryptedHeader;
        char    frData[ frCompressedSize - StrongEncryptedHeader.IVSize - StrongEncryptedHeader.Size - 6];
    }
    else if ((frFlags & FLAG_Encrypted) && ( frCompression == COMP_WzAES ))
    {
        local int lenSalt = 0;
        if (frExtraField.efHeaderID == EH_WzAES)
        {
            switch (frExtraField.Strength)
            {
            case AES128: 
                lenSalt = 8;
                break;
            case AES192: 
                lenSalt = 12;
                break;
            case AES256: 
                lenSalt = 16;
                break;
            }
        }
        uchar   SaltValue[lenSalt];
        ushort  PassVerification;
		uchar   frData[ frCompressedSize - 12 - lenSalt];
		uchar   AuthenticationCode[ 10];
    }
	else if( (frCompressedSize > 0) && (frCompressedSize < 0xFFFFFFFF))
    {
		uchar    frData[ frCompressedSize ];
    }
    else if (frCompressedSize == 0 && (frFlags & FLAG_DescriptorUsedMask))
    {
		// If bit 3 (0x08) of the flags field is set, then the CRC-32 and file sizes were not known when the header was written.
		// Instead there is an additional header ZIPDATADESCR appended after the compressed data.
		// We look for the next signature of the appended header here. 
        local int64 posCurrent = FTell();
        local int64 posNext =  FindFirst(S_ZIPDATADESCR,true,false,false,0.0,1,posCurrent);
        if (posNext >= posCurrent) 
        {
            uchar frData[posNext - posCurrent];

    		SetBackColor( cLtGreen );
		    ZIPDATADESCR dataDescr;
        }
    }

} ZIPFILERECORD <read=ReadZIPFILERECORD, write=WriteZIPFILERECORD>;

// Defines an entry in the directory table
typedef struct {
	SignatureTYPE deSignature;     //0x02014b50
	VERECORD deVersionMadeBy;
	VERECORD deVersionToExtract;
	FLAGTYPE deFlags;
	COMPTYPE deCompression;
	DOSTIME  deFileTime;
	DOSDATE  deFileDate;
	uint     deCrc     <format=hex>;
	uint     deCompressedSize;
	uint     deUncompressedSize;
	ushort   deFileNameLength;
	ushort   deExtraFieldLength;
	ushort   deFileCommentLength;
	ushort   deDiskNumberStart;
	ushort   deInternalAttributes;
	FILEATTRIBUTE deExternalAttributes;
	uint     deHeaderOffset;
	if( deFileNameLength > 0 )
		char     deFileName[ deFileNameLength ];
	local int len = deExtraFieldLength;
	while (len > 0)
	{
		EXTRAFIELD deExtraField;
		len -= deExtraField.efDataSize + 4;
	}
	if( deFileCommentLength > 0 )
		uchar    deFileComment[ deFileCommentLength ];
} ZIPDIRENTRY <read=ReadZIPDIRENTRY>;

// Defines the digital signature
typedef struct {
	SignatureTYPE dsSignature;    //0x05054b50
	ushort   dsDataLength;
	if( dsDataLength > 0 )
		uchar 	dsData[ dsDataLength ];
} ZIPDIGITALSIG;

// Zip64 end of central directory record
typedef struct {
	SignatureTYPE elr64Signature; //0x06064b50
		int64       elr64DirectoryRecordSize;
	if (elr64DirectoryRecordSize > 1)
		VERECORD    elr64VersionMadeBy;
	if (elr64DirectoryRecordSize > 2)
		VERECORD    elr64VersionToExtract;
	if (elr64DirectoryRecordSize > 4)
		uint        el64DiskNumber;
	if (elr64DirectoryRecordSize > 8)
		uint        el64StartDiskNumber;
	if (elr64DirectoryRecordSize > 12)
		int64       el64EntriesOnDisk;
	if (elr64DirectoryRecordSize > 20)
		int64       el64EntriesInDirectory;
	if (elr64DirectoryRecordSize > 28)
		int64       el64DirectorySize;
	if (elr64DirectoryRecordSize > 36)
		int64       el64DirectoryOffset;
	if (elr64DirectoryRecordSize > 44)
	{
        char DataSect [elr64DirectoryRecordSize - 44];
//	    local int len = elr64DirectoryRecordSize - 44;
//	    while (len > 0)
//	    {
//		    EXTRA64FIELD frExtraField;
//		    len -= frExtraField.efDataSize + 4;
//	    }

    }
} ZIP64ENDLOCATORRECORD;

//Zip64 end of central directory locator
typedef struct {
	SignatureTYPE elSignature;    //0x07064b50
	uint     elStartDiskNumber;
	int64    elDirectoryOffset;
	uint     elEntriesInDirectory;
}  ZIP64ENDLOCATOR;

// Defines the end of central directory locator
typedef struct {
	SignatureTYPE elSignature;    //0x06054b50
	ushort   elDiskNumber;
	ushort   elStartDiskNumber;
	ushort   elEntriesOnDisk;
	ushort   elEntriesInDirectory;
	uint     elDirectorySize;
	uint     elDirectoryOffset;
	ushort   elCommentLength;
	if( elCommentLength > 0 )
		char elComment[ elCommentLength ];
} ZIPENDLOCATOR;

//--------------------------------------------

// Custom read functions that allows the name of the
//  of the file to appear in the Template Results.

string ReadZIPFILERECORD( ZIPFILERECORD &file )
{
	if( exists( file.frFileName ) )
		return file.frFileName;
	else
		return "";
}

string ReadZIPDIRENTRY( ZIPDIRENTRY &entry )
{
	if( exists( entry.deFileName ) )
		return entry.deFileName;
	else
		return "";
}

// Custom write function that allows changing
//  the name of the file - note that the file
//  name size cannot be increased

void WriteZIPFILERECORD( ZIPFILERECORD &file, string s )
{
	local int len = Strlen( s );
	if( exists( file.frFileName ) )
	{
		Strncpy( file.frFileName, s, file.frFileNameLength );
		if( len < file.frFileNameLength )
		file.frFileName[len] = 0; //null terminate        
	}
}

//--------------------------------------------

// Define the file
local uint tag;
LittleEndian(); 
while( !FEof() )
{
	// Read a tag
	tag = ReadUInt( FTell() );

	// Read data depending upon tag - should start with 'PK'.
	// Note that when duplicate variables are defined, they
	// are made into an array (see 'Using Templates and Structs'
	// in the help file).
	if( tag == S_ZIPFILERECORD )
	{
		SetBackColor( cLtGray );
		ZIPFILERECORD record;
		if (record.frExtraFieldLength > 0 && record.frExtraField.efHeaderID == EH_Zip64)
		{
			//Printf("%Lu", record.frExtraField.efCompressedSize);
			FSkip(record.frExtraField.efCompressedSize);
		}
	}
	else if( tag == S_ZIPDATADESCR )
	{
		SetBackColor( cLtGreen );
		ZIPDATADESCR dataDescr;
	}
	else if( tag == S_ZIPDIRENTRY )
	{
		SetBackColor( cLtPurple );
		ZIPDIRENTRY dirEntry;
	}
	else if( tag == S_ZIPDIGITALSIG )
	{
		SetBackColor( cLtBlue );
		ZIPDIGITALSIG digitalSig;
	}
	else if( tag == S_ZIP64ENDLOCATORRECORD )
	{
		SetBackColor( cYellow );
		ZIP64ENDLOCATORRECORD end64Locator;
	}
	else if( tag == S_ZIP64ENDLOCATOR )
	{
		SetBackColor( cDkYellow );
		ZIP64ENDLOCATOR end64Locator;
	}
	else if( tag == S_ZIPENDLOCATOR )
	{
		SetBackColor( cLtYellow );
		ZIPENDLOCATOR endLocator;
	}
	else
	{
		Warning( "Unknown ZIP tag encountered. Template stopped." );
		return -1;
	}
}