Contributor: GAYLE DAVIS
program ReadSwag;
{+$X}
uses Dos,Crt;
type
SwagHeader =
RECORD
HeadSize : BYTE; {size of header}
HeadChk : BYTE; {checksum for header}
HeadID : ARRAY [1..5] OF CHAR; {compression type tag}
NewSize : LONGINT; {compressed size}
OrigSize : LONGINT; {original size}
Time : WORD; {packed time}
Date : WORD; {packed date}
Attr : WORD; {file attributes and flags}
BufCRC : LONGINT; {32-CRC of the Buffer }
Swag : STRING[12]; {stored SWAG filename}
Subject : STRING[40]; {snipet subject}
Contrib : STRING[35]; {contributor}
Keys : STRING[70]; {search keys, comma deliminated}
FName : PathStr; {filename (variable length)}
CRC : WORD; {16-bit CRC (immediately follows FName)}
END;
PROCEDURE SWAGView (LzhFile : PathStr);
VAR
Swaghead : Swagheader;
HeadA : ARRAY [1..SIZEOF (Swagheader) ] OF BYTE ABSOLUTE Swaghead;
inFile : FILE; { File to be processed }
J, LZHpos : LONGINT;
numread, i : WORD;
FUNCTION Mksum : BYTE; {calculate check sum For File header }
VAR
i : INTEGER;
b : BYTE;
BEGIN
b := 0;
FOR i := 3 TO Swaghead.headsize + 2 DO b := b + HeadA [i];
mksum := b;
END;
PROCEDURE ShowView;
BEGIN
with Swaghead do
begin
writeln('==================================================');
writeln('Header size = ', HeadSize);
writeln('compressed size = ', NewSize);
writeln('stored SWAG filename = ', Swag);
writeln('snipet subject = ', Subject);
writeln('Contributor = ', Contrib);
writeln('Search keys = ', Keys);
writeln('File name = ', Fname);
end;
END;
BEGIN
Assign(infile,LzhFile);
Reset(infile, 1);
{Goto start of File}
LZHPos := 0;
REPEAT
{ Move to the correct position }
SEEK (inFile, LZHpos);
{Read Fileheader}
BLOCKREAD (inFile, HeadA, SIZEOF (Swagheader), numread);
{ get the position of the next header }
LZHpos := LZHpos + Swaghead.headsize + 2 + Swaghead.Newsize;
{ check the checksum }
i := Mksum;
IF Swaghead.headsize 0 THEN
BEGIN
IF i Swaghead.headchk THEN
BEGIN
{ ERROR : FORMAT ERROR !! }
CLOSE (infile);
EXIT;
END;
ShowView;
END;
UNTIL (Swaghead.headsize = 0);
CLOSE (infile);
END;
BEGIN
SwagView('d:\swag\files\oop.swg');
END.