{$A+,B-,D+,E+,F-,G+,I+,L+,N-,O-,P+,Q+,R+,S+,T+,V+,X+}
{$M 16384,0,655360}
program mklink;
{Builds a Joliet Directory Link Table from all Joliet CDs in all drives.
This table has following content:
- 1 DWORD size designator (=4)
- 1 DWORD number of entries (=n)
- n DWORD Joliet directory sectors
- n DWORD ISO corresponding directory sectors
The name is built from CD ISO label, using numbers&letters, +.JLT extension
This generator program has some limitations:
- every directory must be less than 64K (runtime error 220)
(relax this requires huge pointer arithmetics. Loading single
sectors would degrade MKLINKs performance dramatically.
Huge pointers are easy if allocated memory has offset of zero.)
- directory data for all levels must fit into DOS memory (runtime error 203)
(ISO resticts depth to eight levels, but most writer software
can relax this limitation. You may recompile using Borland DPMI.)
- CD distinction relies on the first eight letters&numbers of volume name
(This limitation is also built into DOSLFN. If someone knows how Win9x
calculates its serial number, tell me, I prefer to use the same
algorithm. CDROMs don't have a serial number like FAT file systems.)
- Empty directories may not be mapped together as intended
(This is by design of Joliet - a better implementation can compare strings
to get better results, but for normal usage, malfunction is meaningless.)
- Although it's possible to create different trees for ISO and Joliet
(i.e. the disc appears different and may show up different directories
with same names under DOS and Win9x - or similar strange or useful
things - e.g. providing a DOS+Win16 and a Win32 executable under the
same name), it's rarely used. I have never seen such a CDROM,
but Nero or WinOnCD (even older versions) are able to create this.
MKLINK and DOSLFN too can't work correctly with such a CDROM.
(Due to program logic, Odi-LFN tools CAN support this situation.)
The "force mode" includes:
- Taking all given drive letters as MSCDEX letters (do not check them)
- Skipping "CeQuadrat Joliet Directory Link Table", burned by WinOnCD
- Overwriting existing files (do not skip if they exist)
Unreadable and Non-Joliet CDs are always skipped.
A check whether LFN and SFN DirEnts are in the same order can be done;
writing a special file, saying "This CD doesn't need a .JLT table",
will be convenient for future DOSLFN.
Attention!
mklink's output file names (.JLT) are subject of change,
as it can assume DOSLFN is running and there is no need to
strip the file name down to 8 characters (as it makes distinction
of different CDs more difficult).
MKLINK has now codepage-dependent Unicode->OEM conversion with DBCS support,
but that's for user's amusing and programmer's debugging only. MKLINK
doesn't rely on comparing names.
Freeware 01/03 haftmann#software}
uses Dos,WinDos,Strings;
{Dos for NameStr}
{WinDos for GetArgCount and GetArgStr}
{Strings for StrCopy, StrPas, StrScan...}
type {boring struct declarations}
PtrRec=record
ofs,sel:Word;
end;
LongRec=record
lo,hi:Word;
end;
WordRec=record
lo,hi:Byte;
end;
PWord=^Word;
PLongInt=^LongInt;
var
drv: Word;
asciidrv: Char;
multiple: Boolean; {whether MKLINK works with more than one drive}
verbosity: Integer;
forcemode: Boolean; {enforce overwriting file and ignoring CeQuadrat}
batchmode: Boolean; {continue manually changing discs until done}
comparing: Boolean; {show compare result of ISO and Joliet tree leaves}
contmode: Boolean; {if at first time no disc in a closed drive, eject}
sameorder: Boolean; {comparing is always done because it's now fast}
timer: Word absolute $40:$6C; {18.2 ms per increment}
function ReadSectors(sec:PChar; cnt:Word; Nr:LongInt):Boolean; assembler;
{Reads some CD sectors; may include VTOC sectors at #16+ depending on
(MS)CDEX running; parameter sorting compatible to Int25/Int26 call}
asm les bx,[sec]
mov si,LongRec[Nr].hi
mov di,LongRec[Nr].lo
mov cx,[drv]
mov dx,[cnt]
mov ax,1508h
int 2Fh
mov al,1
sbb al,0
end;
procedure Idle; assembler;
{releases current time slice to Virtual Machine Manager (Windows, OS/2),
and give DOS and TSRs a hint to do some backgound processing}
asm int 28h
mov ax,1680h {release time slice (PM)}
int 2Fh
mov ah,0Bh {check input status (^C)}
int 21h
end;
function Ioctl(s:PChar):Boolean;
{Maintain a CD IOCTL call (with its brain-damaged structure),
String <s> must contain:
s[0]=control code (3=read, 12=write)
s[1]=number of bytes to read or write
s[2+]=bytes to write or (return) bytes ro read}
type
TDDRH=packed record
len,sub,cmd: Byte;
status: Word;
devname: array[0..7] of Char;
mediadescriptor: Byte;
bufferptr: Pointer;
buffersize: Word;
startsector: LongInt;
volumeptr: LongInt;
end;
var
ddr: TDDRH;
begin
FillChar(ddr,sizeof(ddr),0);
ddr.len:=sizeof(ddr); {28 = $1C}
ddr.cmd:=Byte(s[0]);
ddr.bufferptr:=s+2;
Byte(ddr.buffersize):=Byte(s[1]);
asm push ss
pop es
lea bx,[ddr]
mov cx,[drv]
mov ax,1510h
stc
int 2Fh
mov al,1
sbb al,0
mov [@Result],al
end;
end;
function DetermineVolStart:LongInt;
type
PMsf=^TMsf;
Tmsf=record
f,s,m:Byte;
end;
PAudioDiskInfo=^TAudioDiskInfo;
TAudioDiskInfo=record
cmd: Byte; {=10}
first,last: Byte;
leadout: LongInt;
end;
PAudioTrackInfo=^TAudioTrackInfo;
TAudioTrackInfo=record
cmd: Byte; {=11}
tno: Byte; {track number}
start: LongInt;
ctrl_adr: Byte; {data track if bit 6 is set}
end;
var
tno: Byte;
s: array[0..9] of Char;
begin
StrCopy(s,#3#7#10);
Ioctl(s); {get first and last track number}
for tno:=PAudioDiskInfo(s+2)^.last downto PAudioDiskInfo(s+2)^.first
do begin
StrCopy(s,#3#7#11);
Byte(s[3]):=tno;
Ioctl(s); {get track info: start and type}
if PAudioTrackInfo(s+2)^.ctrl_adr and $40 <>0 then begin
with PMsf(@PAudioTrackInfo(s+2)^.start)^ do begin
DetermineVolStart:=LongInt(m)*4500+s*75+f-150;
end;
exit;
end;
end;
DetermineVolStart:=-1;
end;
function toc(tic:Word):Word;
{returns time elapsed since taking tic, in steps of about 55 ms}
begin
{$Q-}
toc:=Timer-tic; {ignore any overflows here, these are intended!}
{$Q+}
end;
function CD_Status:Word;
var
s: array[0..6] of Char;
begin
StrCopy(s,#3#5#6);
Ioctl(s);
CD_Status:=PWord(s+3)^;
end;
function isatty(fh:Integer):Boolean; assembler;
asm mov bx,[fh]
mov ax,4400h
int 21h
xchg dx,ax
rol al,1 {Bit 7 -> Bit 0}
and al,1
end;
const
Drehstrich: array[0..3] of Char='\|/-';
function CD_Eject:Boolean;
{As Name implies, ejects a CD from current drive; does some message outpus}
var
t,tic:Word;
dr: Integer;
begin
tic:=timer;
Write('Ejecting ',asciidrv,':');
Ioctl(#12#2#1#0); {unlock door if locked (for disc changers)}
CD_Eject:=Ioctl(#12#1#0);
{Assume that every eject must take at least 1.5 seconds.
Some implementations of CD drivers return control immediately,
and door status will not immediately return OPEN, this confuses.}
repeat Idle until toc(tic)>25;
{Win95 CD driver does not return OPEN even if is, to get right state,
you have to query seldom enough - therefore, this "self-lenging"
wait loop between two Ioctls}
dr:=0; t:=2;
repeat
tic:=timer;
repeat Idle until toc(tic)>=t;
if isatty(1) then begin
Write(Drehstrich[dr],#8);
dr:=(dr+1)mod 4;
end;
Inc(t,t); {twice idle time to wait (Win95 requires)}
until CD_Status and 1 <>0; {until drive reports an open door!}
Write(#13,#13:13);
end;
function CD_WaitForClose:Boolean;
{An interactive waiting for next CD. If user does insert no CD, program
stops. If there is a closed door without a CD at first call, this routine
opens the tray. The insertion notification message will be animated.}
label restart;
var
i,v:Integer;
tic,sta: Word;
s: String[70];
begin
s:='Insert next CD';
if multiple then s:=s+' into '+asciidrv+':' else s:=s+',';
s:=s+' or no CD if you want to terminate. '#13;
restart:
sta:=CD_Status;
if sta and 1 <>0 then begin
{$Q-}
contmode:=true;
i:=Length(s); v:=1;
repeat
tic:=timer;
Write(s:i);
Inc(i,v);
if i=80 then v:=-1;
if i=Length(s) then v:=1;
repeat Idle until toc(tic)>=4; {do not ask too often}
sta:=CD_Status;
until sta and 1 =0; {until drive reports a closed door}
tic:=timer;
repeat Idle until toc(tic)>1*18; {wait some seconds}
Write(#13:80);
{$Q+}
end;
if sta and $800 <>0 then begin
if contmode then begin
WriteLn('No CD in drive ',asciidrv,':, aborting program now.');
halt;
end else begin
CD_Eject;
goto restart;
end;
end;
end;
function MapBytes(Nr,len:LongInt):PChar;
{Like true memory mapping, this routine returns a pointer to loaded
sectors. <len> of longint is for dreaming. This routine memorize the size
of block two bytes below the returned pointer.}
var P:PChar;
begin
if len>($10000-2048) then begin
WriteLn('Too large (>=64K) directory structure to map, aborting!');
RunError(220);
end;
Inc(LongRec(len).lo,2);
GetMem(P,LongRec(len).lo);
if not ReadSectors(P+2,LongRec(len).lo shr 11,Nr) then begin
WriteLn('Cannot read sectors from CD drive, aborting!');
RunError(221);
end;
PWord(P)^:=LongRec(len).lo;
MapBytes:=P+2;
end;
procedure UnmapBytes(p:PChar);
{Frees memory, uses the memorized size, therefore, acts as free() C function}
begin
Dec(p,2);
FreeMem(p,PWord(p)^);
end;
type
ee=(le,be);
bedw=array[ee] of LongInt;
bew=array[ee] of Word;
PDirEnt=^TDirEnt;
TDirEnt=record
r: Byte; {the number of bytes in the record (which must be even)}
ea: Byte; {0 [number of sectors in extended attribute record]}
file_start_lbn: bedw; {Logical Block Number (=sector) of file start}
file_size_byte: bedw; {file length in bytes}
date_time: array[0..6] of Byte;
bit_flags: Byte;
interleave_size: Byte; {interleave size}
interleave_skip: Byte; {interleave skip factor}
volume_set_number: bew; {volume set sequence number}
filename: String[1]; {a Pascal string!}
end;
procedure Time_CD2FAT(const de:TDirEnt; var Time:LongInt);
var
dt: TDateTime;
begin
with de do begin
dt.year:= date_time[0]+1900;
dt.month:= date_time[1];
dt.day:= date_time[2];
dt.hour:= date_time[3];
dt.min:= date_time[4];
dt.sec:= date_time[5];
end;
PackTime(dt,Time);
end;
procedure Time_Ascii2FAT(sp:PChar; var Time: LongInt);
var
dt: TDateTime;
s: String[17];
e: Integer;
begin
s[0]:=#17;
Move(sp^,s[1],17);
Val(Copy(s, 1,4),dt.year, e);
Val(Copy(s, 5,2),dt.month,e);
Val(Copy(s, 7,2),dt.day, e);
Val(Copy(s, 9,2),dt.hour, e);
Val(Copy(s,11,2),dt.min, e);
Val(Copy(s,13,2),dt.sec, e);
PackTime(dt,Time);
end;
var
UniXlat: PWord; {pointer to Unicodes}
UniTableLen: Word; {length of table, in Words}
TrailMinLen: Word; {for DBCS type, TrailByte area}
procedure LoadUni;
var
cp: Word; {Code Page}
fname: array[0..12] of Char; {built file name}
ok: Boolean; {Okay flag}
buf: array[0..31] of Byte; {buffer for header parsing}
i: Integer;
f: File; {BlockRead file type}
begin
asm mov ax,6601h
xor bx,bx
int 21h
mov [cp],bx
end;
if cp=0 then exit;
Str(cp:5,fname);
if cp<10000 then fname[0]:='C';
if cp<1000 then fname[1]:='P';
StrCopy(fname+5,'UNI.TBL');
Assign(f,fname); {$I-} Reset(f,1) {$I+};
if IOResult<>0 then begin
WriteLn('Couldn''t open Unicode table file ',fname);
exit;
end;
ok:=false;
BlockRead(f,buf,sizeof(buf));
for i:=0 to HIGH(buf) do case buf[i] of
0: break;
1: begin ok:=true; break; end;
2: begin
if i<=HIGH(buf)-2 then begin
ok:=true;
Inc(i);
TrailMinLen:=PWord(@buf[i])^;
Inc(i);
end;
break;
end;
end;
if not OK then begin
WriteLn('Unicode table file ',fname,' has wrong format.');
Close(f);
exit;
end;
Inc(i);
UniTableLen:=FileSize(f)-i; {in bytes}
Seek(f,i); {start of unicodes}
GetMem(UniXlat,UniTableLen);
BlockRead(f,UniXlat^,UniTableLen); {map all unicodes}
UniTableLen:=UniTableLen div 2; {in words}
Close(f);
end;
procedure uni2oem(w:Word;var s:PChar); assembler;
{Same routine as in DOSLFN, supports DBCS}
asm mov ax,[w]
les di,[s]
les di,es:[di]
cld
cmp ax,80h
jc @@e
push es
push di
les di,[UniXlat]
mov cx,es
jcxz @@nc {no translation without a table}
mov cx,[UniTableLen]
push di
push cx
repne scasw
pop ax
pop di
jne @@NoConv
sub ax,cx
add ax,7Fh {Index 0 is AX=80h}
or ah,ah {>=100h?}
jz @@e1 {1 Byte Character}
dec ah {-100h}
div WordRec[TrailMinLen].hi {AH=TrailIndex, AL=LeadIndex}
xor dx,dx
xchg dh,ah {save TrailIndex, zero AH}
inc ax {1-based}
mov cx,80h
repne scasw {search Index}
mov dl,0FFh {AH is 0}
sub dl,cl {Index 0 -> Leadbyte 80h}
xchg dx,ax {AL=LeadByte, AH=TrailIndex}
pop di
pop es
stosb {write LeadByte}
xchg ah,al
add al,WordRec[TrailMinLen].lo
jmp @@e
@@nc:
or ah,ah {>=100h?}
jz @@e1 {take an ISO-Latin-1 character}
@@NoConv:
mov al,'_' {not convertable char}
@@e1: pop di
pop es
@@e: stosb
xchg ax,di
les di,[s]
stosw {change Offset}
end;
function ununi(d:PChar;s:PWord; l:Integer):PChar;
{copies l Motorola Unicode characters from s to d}
begin
while l<>0 do begin
uni2oem(Swap(s^),d);
Inc(s);
dec(l);
end;
ununi:=d;
end;
procedure ununicode(var s:String);
{unicode-to-ascii conversion; unicode data is big endian}
var
i: Integer;
begin
if odd(length(s)) then exit;
s[0]:=Char(ununi(@s[1],PWord(@s[1]),length(s) div 2)-@s[1]);
end;
var
DbcsLeadByteTable: PWord;
{points to pairs of LeadMinByte/LeadMaxByte, zero-terminated}
procedure PrepareDBCS; assembler;
var
info: array[0..4] of Char;
asm cld
mov ax,6507h
mov bx,0FFFFh
mov cx,5
mov dx,bx
push ss
pop es
mov di,sp
int 21h
les di,es:[di+1]
scasw {skip count word}
mov PtrRec[DbcsLeadByteTable].ofs,di
mov PtrRec[DbcsLeadByteTable].sel,es
end;
function IsDbcsLeadByte(c:Char):Boolean; assembler;
{same as the Windows function}
asm cld
push ds
push si
lds si,[DbcsLeadByteTable]
@@l: lodsw
cmp ax,1
jc @@e
cmp [c],al
jc @@e
cmp ah,[c]
jc @@l
@@e: pop si
pop ds
db 0D6h {SETALC = "sbb al,al" in one byte}
inc al
end;
function LeftStr(s:String; bytes:Integer):String;
{DBCS safe "Left$" function, copies <bytes> or <bytes-1> bytes}
var
i:Integer;
begin
for i:=1 to Length(s) do begin
if IsDbcsLeadByte(s[i]) then Inc(i);
if i>bytes then Dec(bytes);
if i>=bytes then break;
end;
LeftStr:=Copy(s,1,bytes);
end;
function IsRegularDir(const de:TDirEnt): Boolean;
begin
with de do begin
IsRegularDir:=(bit_flags and 2 <>0) {Verzeichnis}
and (filename<>#0)
and (filename<>#1) {nicht . und ..}
end;
end;
function IsBadDirEnt(de:PDirEnt): Boolean;
begin
with de^ do begin
IsBadDirEnt:=odd(r) or (ea<>0) or (r<Length(filename)+33);
end;
end;
procedure ShowRead;
const
dr: Integer=0;
begin
if verbosity=0 then exit;
if not isatty(1) then exit;
write(Drehstrich[dr],#13);
dr:=(dr+1)mod 4;
end;
type
PScan=^TScan;
TScan=object
start_sec, start_len: LongInt;
cur_len: LongInt;
sec: PChar;
de: PDirEnt;
constructor Init(ssec,slen:LongInt);
function Have_DirEnt:Boolean;
procedure Rewind;
function Next_DirEnt(wrap:Boolean):Boolean;
function Suche_Datei(lookfor: LongInt):Boolean;
function Suche_Vrz:Boolean;
function Count_DirEnts:LongInt;
function Locate_File(lbn:LongInt):PDirEnt;
destructor Done;
end;
constructor TScan.Init(ssec,slen:LongInt);
begin
start_sec:=ssec;
start_len:=(slen+2047) and $7FFFF800; {round up to whole sectors}
sec:=MapBytes(ssec,slen); {read in whole structure, we have lot space}
ShowRead;
Rewind;
end;
function TScan.Have_DirEnt:Boolean;
{moves p to the next sector boundary if p points to a tail of a sector
AND l is greater than 2048}
var
a: Word;
begin
if (de^.r=0) and (cur_len>2048) then begin
a:=cur_len mod 2048; {last 11 bits (sector size may change)}
Inc(PChar(de),a); {move pointer forward}
Dec(cur_len,a); {decrease residual length}
end;
Have_DirEnt:=(cur_len<>0) and not IsBadDirEnt(de);
end;
procedure TScan.Rewind;
begin
cur_len:=start_len;
de:=PDirEnt(sec); {rewind}
end;
function TScan.Next_DirEnt(wrap:Boolean):Boolean;
{moves de to the next directory entry,
and wraps to begin if end is reached}
begin
Next_DirEnt:=true;
with de^ do begin
Inc(PChar(de),r);
Dec(cur_len,r);
end;
if not Have_DirEnt then begin
if wrap then Rewind
else Next_DirEnt:=false;
end;
end;
function TScan.Suche_Datei(lookfor: LongInt):Boolean;
{seaches a file with "lookfor" sector in ss in round-robin manner}
var
sde: PDirEnt; {Rundenspeicher}
begin
Suche_Datei:=false;
sde:=de;
repeat
if (de^.bit_flags and 2 =0) {sollte in der Regel sofort treffen!}
and (de^.file_start_lbn[le]=lookfor)
then begin
Suche_Datei:=true;
exit;
end;
Next_DirEnt(true);
until sde=de;
end;
function TScan.Suche_Vrz:Boolean;
{searches next directory in ss, round-robin}
var
sde: PDirEnt; {Rundenspeicher}
begin
Suche_Vrz:=false;
sde:=de;
repeat
if IsRegularDir(de^)
then begin
Suche_Vrz:=true;
exit;
end;
Next_DirEnt(true);
until sde=de;
end;
function TScan.Count_DirEnts:LongInt;
{D: Counts files and subdirs in p separately
O: LOWORD=number of files
HIWORD=number of subdirs, not counting . and ..}
var
cnt: LongRec;
begin
cnt.lo:=0;
cnt.hi:=Word(-2);
repeat
if de^.bit_flags and 2 =0
then Inc(cnt.lo)
else Inc(cnt.hi);
until not Next_DirEnt(false);
Rewind;
Count_DirEnts:=LongInt(cnt);
end;
function TScan.Locate_File(lbn:LongInt):PDirEnt;
{D: Searches for a file matching <lbn>, or first file if <lbn>=0
O: matched DirEnt, nil when not found}
begin
Locate_File:=nil;
repeat
if (de^.bit_flags and 2 =0)
and ((lbn=0) or (de^.file_start_lbn[le]=lbn)) then begin
Locate_File:=de;
Rewind;
exit;
end;
until not Next_DirEnt(false);
Rewind;
end;
destructor TScan.Done;
begin
UnmapBytes(sec); {free memory}
end;
var
Num_Links: LongInt;
LTab,STab: array[0..$0FFF] of LongInt; {link data (max. 32K)}
function InSTab(k:LongInt):Boolean;
{D: Checks whether <k> is already in STab}
var
i: Integer;
begin
InSTab:=false;
for i:=0 to Num_Links-1 do begin
if STab[i]=k then begin
InSTab:=true;
exit;
end;
end;
end;
procedure DisplayMatch(lsec,ssec:LongInt;
lname,sname:string; depth:Byte; const comment:string);
begin
if Verbosity<>0 then begin
if 35-depth-length(lname)<0 then begin
lname:=LeftStr(lname,35-depth-3)+'...';
end;
if 8-length(sname)<0 then begin
sname:=LeftStr(sname,8-3)+'...';
end;
Write('':depth,lname,'':35-depth-length(lname),lsec:6,
' <=> ',sname,'':8-length(sname),ssec:7,' (',comment,')');
if Verbosity>=2 then writeln else write('':15-length(comment),#13);
end;
LTab[Num_Links]:=lsec;
STab[Num_Links]:=ssec;
Inc(Num_Links);
end;
procedure CheckOrder(var ls,ss:TScan);
{Works with the logic of present (for files) and future (for dirs) DOSLFN}
var
i:Integer;
l:LongInt;
begin
ls.Rewind;
ss.Rewind;
repeat
l:=ls.de^.file_start_lbn[le];
if ls.de^.bit_flags and 2 <>0 then begin
if IsRegularDir(ls.de^) then begin
ss.Suche_Vrz; {simply take the next directory}
for i:=Num_Links-1 downto 0 do
if LTab[i]=l then begin
if STab[i]<>ss.de^.file_start_lbn[le] then begin
sameorder:=false;
exit;
end;
break;
end; {with correct program logic, the loop must always find a hit}
end;
end else begin
ss.Suche_Datei(l); {should never return FALSE}
end;
ss.Next_DirEnt(true);
until not ls.Next_DirEnt(false);
exit;
end;
function MakeDirLink(lsec,llen,ssec,slen:LongInt;
const lname,sname:string; depth, ldetect:Byte):Byte;
{possible return values:
* 0 = Empty directory (this may be propagated)
* 1 = No Match (sure)
* 255 = Match (sure)
* graduated "don't know exactly": all values between 2 and 254}
label exi;
var
sde: PDirEnt;
ls,ss: TScan; {two objects for scanning Joliet and ISO directory}
lcount:LongInt; {counter for directories and files}
begin
ls.Init(lsec,llen); {read entire LFN directory}
ss.Init(ssec,slen); {read entire SFN directory, prepare search}
lcount:=ls.Count_DirEnts;
if ldetect=255 then begin
DisplayMatch(lsec,ssec,lname,sname,depth,'known');
if lcount=0 then goto exi; {return immediately if CD is completely empty}
end else begin
{Check #1: Number of directories and files must be the same}
if lcount<>ss.Count_DirEnts then begin
ldetect:=1;
goto exi;
end;
{Check #2: If there is no DirEnt at all, it is an empty directory.
Because empty dir is an empty dir, eventually wrong linkage
due to wrong order does not bother. Return 0}
if lcount=0 then begin
DisplayMatch(lsec,ssec,lname,sname,depth,'EMPTY');
goto exi;
end;
{Check #3: If there are files, there must exist direct companions.
Only one file is checked here; if matching, MakeDirLink return 255}
if LongRec(lcount).lo<>0 then begin
sde:=ls.Locate_File(0);{return NIL is internal error}
if ss.Locate_File(sde^.file_start_lbn[le])<>nil then begin
ldetect:=255; {A match is now sure}
DisplayMatch(lsec,ssec,lname,sname,depth,'file inside');
end else begin
ldetect:=1;
goto exi;
end;
end;
end;
{Check #4: If there is no subtree, return with ldetect, which
must be 255 when no subtree is there due to program logic.}
if LongRec(lcount).hi=0 then goto exi;
{Check #5 and recursion: Do with all subdirs, but propagate 1}
if ldetect=0 then ldetect:=1;
repeat
if IsRegularDir(ls.de^) then begin
UnUnicode(ls.de^.filename); {needed for display and sorting}
ss.Suche_Vrz; {seek to first (or next) DirEnt}
sde:=ss.de; {start round-robin search}
repeat
{For speed, SFN directories that are already in the list should not
scanned again}
if not InSTab(ss.de^.file_start_lbn[le])
then case MakeDirLink(
ls.de^.file_start_lbn[le],ls.de^.file_size_byte[le],
ss.de^.file_start_lbn[le],ss.de^.file_size_byte[le],
ls.de^.filename,
ss.de^.filename,
depth+1,0) of
0: begin
if ldetect<>255 then ldetect:=0;
break; {silence on empty subtrees}
end;
255: begin {Callee has a match}
{If we had no match from files, now we can match due to matching subtree.
The inner loop can be exited}
if ldetect<>255 then begin
DisplayMatch(lsec,ssec,lname,sname,depth,'subtree');
ldetect:=255;
end;
break; {exit search loop, subtree had given out the match}
end;
end{case};
ss.Next_DirEnt(true);
ss.Suche_Vrz;
until sde=ss.de;
end;
ss.Next_DirEnt(true);
until not ls.Next_DirEnt(false);
if ldetect=0 then begin
DisplayMatch(lsec,ssec,lname,sname,depth,'EMPTY subtree');
end;
exi:
if (ldetect=255) and sameorder then CheckOrder(ls,ss);
ss.Done;
ls.Done;
MakeDirLink:=ldetect;
end;
type
PVolDesc=^TVolDesc;
TVolDesc=record
id: array[0..7] of Char; {#n'CD001'#1#0, n=1,2,255}
system_id: array[0..31] of Char;
volume_id: array[0..31] of Char;
zero1: array[0..7] of Byte;
total_sec_number: bedw;
joliet_id: array[0..31] of Char;
volume_set_size: bew; {1}
volume_sequence_number: bew; {1}
sector_size: bew; {2048}
path_table_length: bedw;
le_path_table_sec: LongInt;
le_path_table_2_sec: LongInt;
be_path_table_sec: LongInt;
be_path_table_2_sec: LongInt;
root_directory_record: TDirEnt; {array[0..33] of Byte}
volume_set_id: array[0..127] of Char;
publisher_id: array[0..127] of Char;
data_preparer_id: array[0..127] of Char;
application_id: array[0..127] of Char;
copyright_file_id: array[0..36] of Char;
abstract_file_id: array[0..36] of Char;
bibliographical_file_id: array[0..36] of Char;
time_creation: array[0..16] of Char;
time_modification: array[0..16] of Char;
time_expire: array[0..16] of Char;
time_effective: array[0..16] of Char;
end;
type
PVD_info=^TVD_info;
TVD_info=record
dir_sec, dir_len: LongInt;
end;
procedure ScanVDInfo(sec:PChar; var vd: TVD_Info);
begin
with PVolDesc(sec)^.root_Directory_record do begin
vd.dir_sec:=file_start_lbn[le];
vd.dir_len:=file_size_byte[le];
end;
end;
function MkVol8(S:PChar):NameStr;
{Assumes S is already right-trimmed}
var
i: Integer;
h: array[0..8] of Char;
begin
i:=0;
repeat
case s^ of
'0'..'9','A'..'Z','a'..'z': begin
h[i]:=s^; Inc(i); {take numbers and letters only}
end;
#0: break; {leave repeat_until}
end;
Inc(s);
until i=8;
h[i]:=#0;
MkVol8:=StrPas(h);
end;
function TrimRight(S:PChar):String;
{Assumes that S has 32 characers, leaves S right trimmed}
var
i: Integer;
begin
for i:=31 downto 0 do begin
if s[i] in [#0,' '] then s[i]:=#0 else break;
end;
TrimRight:=StrPas(S);
end;
const
link_id:array[0..37] of Char='CeQuadrat Joliet directory link table';
var
link_data:PLongInt; {points to a copy of table above, for comparing}
function TablesEqual:Boolean;
{compares <link_data> (found as CeQuadrat table on CD) against
found values in Num_Links, STab, and LTab}
label w;
var
ldp: PLongInt;
i,j: Integer;
s,l: LongInt;
begin
TablesEqual:=false;
ldp:=link_data;
if ldp^<>Num_Links then exit; {trivial root sectors are included}
Inc(ldp);
for i:=0 to Num_Links-1 do begin
l:=ldp^; Inc(ldp);
s:=ldp^; Inc(ldp);
for j:=0 to Num_Links-1 do begin
if s=STab[j] then begin {found corresponding}
if l=LTab[j] then goto w {equal, next in outer loop}
else exit; {not equal, return with FALSE}
end;
end;
w:end;
TablesEqual:=true;
end;
function ProcessDrive(d:Char):Boolean;
label nx,fe,eject,exi; {skip eject exit}
type
Apres=(_PVD,_SVD,_TVD,_LinkTable);
var
sec: PChar; {on heap to preserve stack}
present: set of Apres;
i: Integer;
tic: Word;
VolStart,l: LongInt;
lrec: LongRec absolute l;
ldptr: PLongInt;
secidx: Integer;
vol8: namestr;
Time,VTime,FTime: LongInt;
lvol,svol: string[32]; {CD volume strings}
pvd,svd: TVD_Info;
f: File;
begin
ProcessDrive:=false;
asciidrv:=d;
drv:=Ord(d)-Ord('A'); {set global variables}
if batchmode then CD_WaitForClose;
Write('Drive ',d,': '); Flush(output);
present:=[];
tic:=timer;
VolStart:=DetermineVolStart;
if VolStart<0 then begin
WriteLn('SKIP: No data tracks found');
goto exi;
end;
GetMem(sec,2048);
for i:=0 to 10 do begin
if not ReadSectors(sec,1,VolStart+16+i) then begin
WriteLn('SKIP: Cannot read VTOC #',i);
FreeMem(sec,2048);
goto exi;
end;
if StrLComp(sec+1,'CD001'#1,6)<>0 then begin
WriteLn('SKIP: Wrong Volume Descriptor at #',i);
goto fe;
end;
case sec[0] of
#1: begin
Include(present,_PVD);
svol:=TrimRight(PVolDesc(sec)^.volume_id);
vol8:=MkVol8(PVolDesc(sec)^.volume_id);
ScanVDInfo(sec,pvd);
Time_CD2FAT(PVolDesc(sec)^.root_directory_record,Time);
if PVolDesc(sec)^.time_modification[0]<>'0' {given?}
then Time_Ascii2FAT(PVolDesc(sec)^.time_modification,VTime)
else VTime:=Time; {they should be equal in any case}
end;
#2: if (PWord(sec+88)^=$2F25) {'%/'}
and (sec[90] in ['@','C','E']) then begin {Joliet signature}
ScanVDInfo(sec,svd);
ununi(PVolDesc(sec)^.volume_id,PWord(@PVolDesc(sec)^.volume_id),32);
lvol:=TrimRight(PVolDesc(sec)^.volume_id);
Include(present,_SVD);
end;
#255: begin
Include(present,_TVD);
break; {leave "for" loop}
end;
end;
end;
Inc(i);
if present<>[_PVD.._TVD] then begin
WriteLn('SKIP: No valid Joliet Descriptor found');
goto fe;
end;
ReadSectors(sec,1,VolStart+16+i);
if strcomp(sec,link_id)=0 then begin
if not ForceMode and (VolStart=0) then begin
WriteLn('SKIP: Found "',link_id,'", check with /f');
goto fe;
end;
l:=PLongInt(sec+$2C)^;
if l>$0FFF then begin {should fit in 32K}
WriteLn('WARNING: found a too long "',link_id,'" with ',l,' entries');
end else begin
lrec.hi:=4+l*8; {memory usage}
GetMem(link_data,lrec.hi);
secidx:=$2C; {data follows from there}
ldptr:=link_data;
repeat
lrec.lo:=2048-secidx; {get length in this sector}
if lrec.lo>lrec.hi then lrec.lo:=lrec.hi; {limit length}
Move(sec[secidx],ldptr^,lrec.lo); {copy bytes}
Inc(PChar(ldptr),lrec.lo); {increment destination ptr}
Dec(lrec.hi,lrec.lo); {decrement residual length}
if lrec.hi=0 then break; {all done}
Inc(i); {read next link data sector}
ReadSectors(sec,1,VolStart+16+i);
secidx:=0; {take whole sector}
until false;
end;
end;
Assign(f,vol8+'.JLT'); {.JLT stands for Joliet Link Table}
if not ForceMode then begin {don't look for CeQuadrat and present file}
{$I-}Reset(f,1);{$I+}
if IOResult=0 then begin
GetFTime(f,FTime);
Close(f);
if VTime=FTime then begin
WriteLn('SKIP: link table ',FileRec(f).name,' already present');
goto fe;
end else if verbosity>=2 then begin
WriteLn('INFO: link table ',FileRec(f).name,' present, but out of date');
end;
end;
end;
FreeMem(sec,2048);
{now: action!}
sameorder:=true;
Num_Links:=0;
writeln('Joliet_Name','LBN':21,' <=> ISO_Name LBN (link_reason)');
MakeDirLink(svd.dir_sec,svd.dir_len,pvd.dir_sec,pvd.dir_len,
lvol,svol,1,255);
if verbosity=1 then write(#13:79); {79 spaces and 1 #13 character}
if comparing then begin
Write('INFO: ISO and Joliet trees have ');
if sameorder
then WriteLn('same order.')
else WriteLn('DIFFERENT order! DOSLFN needs a .JLT file.');
end;
{now save the result}
write('Found ',Num_Links,' links');
tic:=toc(tic) div 18;
case tic of
0:; {do nothing}
1: Write(' in one second');
else Write(' in ',tic,' seconds');
end;
if link_data<>nil then begin
if TablesEqual then begin
Write(', ignore same table on CD');
end else begin
WriteLn(', found DIFFERENT VERSION of (yet ignored)');
Write('"',link_id,'"');
end;
end;
write(', now writing ',FileRec(f).name);
l:=sizeof(LongInt); {=4}
{$I-}
Rewrite(f,l); {all DWORDs}
BlockWrite(f,l,1); {first byte declares data size, 1, 2, or 4}
BlockWrite(f,Num_Links,1); {second element address depends on data size}
BlockWrite(f,STab,Num_Links);
BlockWrite(f,LTab,Num_Links);
SetFTime(f,VTime);
Close(f);
{$I+}
if IOResult<>0 then begin
WriteLn;
Write('ERROR: cannot write data to file ',FileRec(f).name);
end;
nx:
WriteLn;
goto eject;
fe:
FreeMem(sec,2048);
eject:
if link_data<>nil then begin
FreeMem(link_data,4+link_data^*8);
link_data:=nil;
end;
exi:
if batchmode then CD_Eject;
end;
var
drvs: array[0..26] of Char; {MSCDEX drive letter list}
procedure setdrv; assembler;
asm mov bx,0
mov ax,1500h
int 2fh
push bx {save count}
push ds
pop es
mov bx,offset drvs
mov ax,150Dh
int 2Fh
pop cx
@@l: add byte ptr [bx],'A' {make letters}
inc bx
loop @@l
mov byte ptr [bx],0 {terminate list}
end;
procedure Usage;
begin
WriteLn('MKLINK reads all Joliet CDs and creates Link Tables for use with DOSLFN');
WriteLn('Options: /? Get Help, /f force mode, /v more verbose, /v- less verbose');
WriteLn(#9' /b batch process (ejects CD, continues after inserting another CD)');
WriteLn(#9' /c compare order of ISO and Joliet tree leaves in means of DOSLFN');
WriteLn('Normal letters are drive letters to scan for (with or without colon :)');
WriteLn('haftmann#software, Freeware 12/02');
halt;
end;
var
sp,spa: PChar;
i: integer;
arg: array[0..7] of Char;
newdrvs: array[0..26] of Char;
begin
FileMode:=0;
verbosity:=1;
SetDrv;
sp:=newdrvs;
for i:=1 to GetArgCount do begin
GetArgStr(arg,i,sizeof(arg));
StrUpper(arg);
spa:=arg;
case spa^ of
'-','/': repeat
Inc(spa);
case spa^ of
'V': case spa[1] of
'-': begin Dec(verbosity); Inc(spa); end;
else Inc(verbosity);
end;
'F': forcemode:=true;
'B': batchmode:=true;
'C': comparing:=true;
#0: break; {exit the REPEAT-UNTIL loop}
else Usage; {wrong or -h parameter given}
end;
until false;
'A'..'Z': repeat
if (not forcemode) and (StrScan(drvs,spa^)=nil) then begin
WriteLn('Drive ',arg[0],': is not a CDROM drive, ignoring it');
end else begin
sp^:=spa^; Inc(sp);
end;
Inc(spa);
if spa^=':' then Inc(spa);
if not (spa^ in [#0,'A'..'Z']) then Usage; {letters must follow}
until spa^=#0;
else Usage;
end;
end;
if sp<>newdrvs then StrCopy(drvs,newdrvs); {copy user preference}
LoadUni;
PrepareDBCS;
multiple:=StrLen(drvs)>1;
repeat
sp:=drvs;
while sp^<>#0 do begin
ProcessDrive(sp^);
Inc(sp);
end;
until not batchmode;
end.
(*
ISO9660 Simplified for DOS/Windows
by Philip J. Erdelsky
75746.3411@compuserve.com
http://www.alumni.caltech.edu/~pje/
1. Introduction
We weren't sure about it a few years ago, but by now it should be clear
to everyone that CD-ROM's are here to stay. Most PC's are equipped with
CD-ROM readers, and most major PC software packages are being
distributed on CD-ROM's.
Under DOS (and Windows, which uses the DOS file system) files are
written to both hard and floppy disks with a so-called FAT (File
Allocation Table) file system.
Files on a CD-ROM, however, are written to a different standard, called
ISO9660. ISO9660 is rather complex and poorly written, and obviously
contains a number of diplomatic compromises among advocates of DOS,
UNIX, MVS and perhaps other operating systems.
The simplified version presented here includes only features that would
normally be found on a CD-ROM to be used in a DOS system and which are
supported by the Microsoft MS-DOS CD-ROM Extensions (MSCDEX). It is
based on ISO9660, on certain documents regarding MSCDEX (version 2.10),
and on the contents of some actual CD-ROM's.
Where a field has a specific value on a CD-ROM to be used with DOS, that
value is given in this document. However, in some cases a brief
description of values for use with other operating systems is given in
square brackets.
ISO9660 makes provisions for sets of CD-ROM's, and apparently even
permits a file system to span more than one CD-ROM. However, this
feature is not supported by MSCDEX.
3. Files
The directory structure on a CD-ROM is almost exactly like that on a DOS
floppy or hard disk. (It is presumed that the reader of this document is
reasonably familiar with the DOS file system.) For this reason, DOS and
Windows applications can read files from a CD-ROM just as they would
from a floppy or hard disk.
There are only a few differences, which do not affect most applications:
(1) The root directory contains the notorious "." and ".." entries,
just like any other directory.
(2) There is no limit, other than disk capacity, to the size of the
root directory.
(3) The depth of directory nesting is limited to eight levels,
including the root. For example, if drive E: contains a CD-ROM,
a file such as E:\D2\D3\D4\D5\D6\D7\D8\FOO.TXT is permitted but
E:\D2\D3\D4\D5\D6\D7\D8\D9\FOO.TXT is not.
(4) If a CD-ROM is to be used by a DOS system, file names and
extensions must be limited to eight and three characters,
respectively, even though ISO9660 permits longer names and
extensions.
(5) ISO9660 permits only capital letters, digits and underscores in
a file or directory name or extension, but DOS also permits a
number of other punctuation marks.
(6) ISO9660 permits a file to have an extension but not a name, but
DOS does not.
(7) DOS permits a directory to have an extension, but ISO9660 does
not.
(8) Directories on a CD-ROM are always sorted, as described below.
Of course, neither DOS, nor UNIX, nor any other operating system can
WRITE files to a CD-ROM as it would to a floppy or hard disk, because a
CD-ROM is not rewritable. Files must be written to the CD-ROM by a
special program with special hardware.
4. Sectors
The information on a CD-ROM is divided into sectors, which are numbered
consecutively, starting with zero. There are no gaps in the numbering.
Each sector contains 2048 8-bit bytes. (ISO9660 apparently permits other
sector sizes, but the 2048-byte size seems to be universal.)
When a number of sectors are to be read from the CD-ROM, they should be
read in order of increasing sector number, if possible, since that is
the order in which they pass under the read head as the CD-ROM rotates.
Most implementations arrange the information so sectors will be read in
this order for typical file operations, although ISO9660 does not
require this in all cases.
The order of bytes within a sector is considered to be the order in
which they appear when read into memory; i.e., the "first" bytes are
read into the lowest memory addresses. This is also the order used in
this document; i.e., the "first" bytes in any list appear at the top of
the list.
5. Character Sets
Names and extensions of files and directories, the volume name, and some
other names are expressed in standard ASCII character codes (although
ISO9660 does not use the name ASCII). According to ISO9660, only capital
letters, digits, and underscores are permitted. However, DOS permits
some other punctuation marks, which are sometimes found on CD-ROM's, in
apparent defiance of ISO9660.
MSCDEX does offer support for the kanji (Japanese) character set.
However, this document does not cover kanji.
6. Sorting Names or Extensions
Where ISO9660 requires file or directory names or extensions to be
sorted, the usual ASCII collating sequence is used. That is, two
different names or extensions are compared as follows:
(1) ASCII blanks (32) are added to the right end of the shorter
name or extension, if necessary, to make it as long as the
longer name or extension.
(2) The first (leftmost) position in which the names or extensions
are not identical determines the order. The name or extension
with the lower ASCII code in that position appears first in the
sorted order.
7. Multiple-Byte Values
A 16-bit numeric value (usually called a word) may be represented on a
CD-ROM in any of three ways:
Little Endian Word: The value occupies two consecutive bytes, with
the less significant byte first.
Big Endian Word: The value occupies two consecutive bytes, with
the more significant byte first.
Both Endian Word: The value occupies FOUR consecutive bytes; the
first and second bytes contain the value expressed as a little
endian word, and the third and fourth bytes contain the same
value expressed as a big endian word.
A 32-bit numeric value (usually called a double word) may be represented
on a CD-ROM in any of three ways:
Little Endian Double Word: The value occupies four consecutive
bytes, with the least significant byte first and the other bytes
in order of increasing significance.
Big Endian Double Word: The value occupies four consecutive bytes,
with the most significant first and the other bytes in order of
decreasing significance.
Both Endian Double Word: The value occupies EIGHT consecutive
bytes; the first four bytes contain the value expressed as a
little endian double word, and the last four bytes contain the
same value expressed as a big endian double word.
8. The First Sixteen Sectors are Empty
The first sixteen sectors (sector numbers 0 to 15, inclusive) contain
nothing but zeros. ISO9660 does not define the contents of these
sectors, but for DOS they are apparently always written as zeros.
They are apparently reserved for use by systems that can be booted from
a CD-ROM.
9. The Volume Descriptors
Sector 16 and a few of the following sectors contain a series of volume
descriptors. There are several kinds of volume descriptor, but only two
are normally used with DOS. Each volume descriptor occupies exactly one
sector.
The last volume descriptors in the series are one or more Volume
Descriptor Set Terminators. The first seven bytes of a Volume Descriptor
Set Terminator are 255, 67, 68, 48, 48, 49 and 1, respectively. The
other 2041 bytes are zeros. (The middle bytes are the ASCII codes for
the characters CD001.)
The only volume descriptor of real interest under DOS is the Primary
Volume Descriptor. There must be at least one, and there is usually only
one. However, some CD-ROM's have two or more identical Primary Volume
Descriptors. The contents of a Primary Volume Descriptor are as follows:
length
in bytes contents
-------- ---------------------------------------------------------
1 1
6 67, 68, 48, 48, 49 and 1, respectively (same as Volume
Descriptor Set Terminator)
1 0
32 system identifier
32 volume identifier
8 zeros
8 total number of sectors, as a both endian double word
32 zeros
4 1, as a both endian word [volume set size]
4 1, as a both endian word [volume sequence number]
4 2048 (the sector size), as a both endian word
8 path table length in bytes, as a both endian double word
4 number of first sector in first little endian path table,
as a little endian double word
4 number of first sector in second little endian path table,
as a little endian double word, or zero if there is no
second little endian path table
4 number of first sector in first big endian path table,
as a big endian double word
4 number of first sector in second big endian path table,
as a big endian double word, or zero if there is no
second big endian path table
34 root directory record, as described below
128 volume set identifier
128 publisher identifier
128 data preparer identifier
128 application identifier
37 copyright file identifier
37 abstract file identifier
37 bibliographical file identifier
17 date and time of volume creation
17 date and time of most recent modification
17 date and time when volume expires
17 date and time when volume is effective
1 1
1 0
512 reserved for application use (usually zeros)
653 zeros
The first 11 characters of the volume identifier are returned as
the volume identifier by standard DOS system calls and utilities.
Other identifiers are not used by DOS, and may be filled with ASCII
blanks (32).
Each date and time field is of the following form:
length
in bytes contents
-------- ---------------------------------------------------------
4 year, as four ASCII digits
2 month, as two ASCII digits, where
01=January, 02=February, etc.
2 day of month, as two ASCII digits, in the range
from 01 to 31
2 hour, as two ASCII digits, in the range from 00 to 23
2 minute, as two ASCII digits, in the range from 00 to 59
2 second, as two ASCII digits, in the range from 00 to 59
2 hundredths of a second, as two ASCII digits, in the range
from 00 to 99
1 offset from Greenwich Mean Time, in 15-minute intervals,
as a twos complement signed number, positive for time
zones east of Greenwich, and negative for time zones
west of Greenwich
If the date and time are not specified, the first 16 bytes are all ASCII
zeros (48), and the last byte is zero.
Other kinds of Volume Descriptors (which are normally ignored by DOS)
have the following format:
length
in bytes contents
-------- ---------------------------------------------------------
1 neither 1 nor 255
6 67, 68, 48, 48, 49 and 1, respectively (same as Volume
Descriptor Set Terminator)
2041 other things
10. Path Tables
The path tables normally come right after the volume descriptors.
However, ISO9660 merely requires that each path table begin in the
sector specified by the Primary Volume Descriptor.
The path tables are actually redundant, since all of the information
contained in them is also stored elsewhere on the CD-ROM. However, their
use can make directory searches much faster.
There are two kinds of path table -- a little endian path table, in
which multiple-byte values are stored in little endian order, and a big
endian path table, in which multiple-byte values are stored in big
endian order. The two kinds of path tables are identical in every other
way.
A path table contains one record for each directory on the CD-ROM
(including the root directory). The format of a record is as follows:
length
in bytes contents
-------- ---------------------------------------------------------
1 N, the name length (or 1 for the root directory)
1 0 [number of sectors in extended attribute record]
4 number of the first sector in the directory, as a
double word
2 number of record for parent directory (or 1 for the root
directory), as a word; the first record is number 1,
the second record is number 2, etc.
N name (or 0 for the root directory)
0 or 1 padding byte: if N is odd, this field contains a zero; if
N is even, this field is omitted
According to ISO9660, a directory name consists of at least one and not
more than 31 capital letters, digits and underscores. For DOS the upper
limit is eight characters.
A path table occupies as many consecutive sectors as may be required to
hold all its records. The first record always begins in the first byte
of the first sector. Except for the single byte described above, no
padding is used between records; hence the last record in a sector is
usually continued in the next following sector. The unused part of the
last sector is filled with zeros.
The records in a path table are arranged in a precisely specified order.
For this purpose, each directory has an associated number called its
level. The level of the root directory is 1. The level of each other
directory is one greater than the level of its parent. As noted above,
ISO9660 does not permit levels greater than 8.
The relative positions of any two records are determined as follows:
(1) If the levels are different, the directory with the lower level
appears first. In particular, this implies that the root
directory is always represented by the first record in the
table, because it is the only directory with level 1.
(2) If the levels are identical, but the directories have different
parents, then the directories are in the same relative
positions as their parents.
(3) Directories with the same level and the same parent are
arranged in the order obtained by sorting on their names, as
described in Section 6.
11. Directories
A directory consists of a series of directory records in one or more
consecutive sectors. However, unlike path records, directory records may
not straddle sector boundaries. There may be unused space at the end of
each sector, which is filled with zeros.
Each directory record represents a file or directory. Its format is as
follows:
length
in bytes contents
-------- ---------------------------------------------------------
1 R, the number of bytes in the record (which must be even)
1 0 [number of sectors in extended attribute record]
8 number of the first sector of file data or directory
(zero for an empty file), as a both endian double word
8 number of bytes of file data or length of directory,
excluding the extended attribute record,
as a both endian double word
1 number of years since 1900
1 month, where 1=January, 2=February, etc.
1 day of month, in the range from 1 to 31
1 hour, in the range from 0 to 23
1 minute, in the range from 0 to 59
1 second, in the range from 0 to 59
(for DOS this is always an even number)
1 offset from Greenwich Mean Time, in 15-minute intervals,
as a twos complement signed number, positive for time
zones east of Greenwich, and negative for time zones
west of Greenwich (DOS ignores this field)
1 flags, with bits as follows:
bit value
------ ------------------------------------------
0 (LS) 0 for a norma1 file, 1 for a hidden file
1 0 for a file, 1 for a directory
2 0 [1 for an associated file]
3 0 [1 for record format specified]
4 0 [1 for permissions specified]
5 0
6 0
7 (MS) 0 [1 if not the final record for the file]
1 0 [file unit size for an interleaved file]
1 0 [interleave gap size for an interleaved file]
4 1, as a both endian word [volume sequence number]
1 N, the identifier length
N identifier
P padding byte: if N is even, P = 1 and this field contains
a zero; if N is odd, P = 0 and this field is omitted
R-33-N-P unspecified field for system use; must contain an even
number of bytes
The length of a directory includes the unused space, if any, at the ends
of sectors. Hence it is always an exact multiple of 2048 (the sector
size). Since every directory, even a nominally empty one, contains at
least two records, the length of a directory is never zero.
All fields in the first record (sometimes called the "." record) refer
to the directory itself, except that the identifier length is 1, and the
identifier is zero. The root directory record in the Primary Volume
Descriptor also has this format.
All fields in the second record (sometimes called the ".." record) refer
to the parent directory, except that the identifier length is 1, and the
identifier is 1. The second record in the root directory refers to the
root directory.
The identifier for a subdirectory is its name. The identifier for a file
consists of the following fields, in the order given:
(1) The name, consisting of the ASCII codes for at least one and
not more than eight capital letters, digits and underscores.
(2) If there is an extension, the ASCII code for a period (46). If
there is no extension, this field is omitted.
(3) The extension, consisting of the ASCII codes for not more than
three capital letters, digits and underscores. If there is no
extension, this field is omitted.
(4) The ASCII code for a semicolon (59).
(5) The ASCII code for 1 (49). [On other systems, this is the
version number, consisting of the ASCII codes for a sequence of
digits representing a number between 1 and 32767, inclusive.]
Some implementations for DOS omit (4) and (5), and some use punctuation
marks other than underscores in file names and extensions.
Directory records other than the first two are sorted as follows:
(1) Records are sorted by name, as described above.
(2) Every series of records with the same name is sorted by
extension, as described above. For this purpose, a record
without an extension is sorted as though its extension
consisted of ASCII blanks (32).
(3) [On other systems, every series of records with the same name
and extension is sorted in order of decreasing version number.]
(4) [On other systems, two records with the same name, extension
and version number are permitted, if the first record is an
associated file.]
[ISO9660 permits names containing more than eight characters and
extensions containing more than three characters, as long as both of
them together contain no more than 30 characters.]
It is apparently permissible under ISO9660 to use two or more
consecutive records to represent consecutive pieces of the same file.
Bit 7 of the flags byte is set in every record except the last one.
However, this technique seems pointless and is apparently not used. It
is not supported by MSCDEX.
Interleaving is another technique that is apparently seldom used. It is
not supported by MSCDEX (version 2.10).
12. Arrangement of Directory and Data Sectors
ISO9660 does not specify the order of directory or file sectors. It
merely requires that the first sector of each directory or file be in
the location specified by its directory record, and that the sectors for
directories and non-interleaved files be consecutive.
However, most implementations arrange the directories so each directory
follows its parent, and the data sectors for the files in each directory
lie immediately after the directory and immediately before the next
following directory. This appears to be an efficient arrangement for
most applications.
Some implementations go one step further and order the directories in
the same manner as the corresponding path table records.
const
oem_uni_tab: array[#$80..#$FF] of word=( {here: code page 437}
$00C7, $00FC, $00E9, $00E2, $00E4, $00E0, $00E5, $00E7,
$00EA, $00EB, $00E8, $00EF, $00EE, $00EC, $00C4, $00C5,
$00C9, $00E6, $00C6, $00F4, $00F6, $00F2, $00FB, $00F9,
$00FF, $00D6, $00DC, $00A2, $00A3, $00A5, $20A7, $0192,
$00E1, $00ED, $00F3, $00FA, $00F1, $00D1, $00AA, $00BA,
$00BF, $2310, $00AC, $00BD, $00BC, $00A1, $00AB, $00BB,
$2591, $2592, $2593, $2502, $2524, $2561, $2562, $2556,
$2555, $2563, $2551, $2557, $255D, $255C, $255B, $2510,
$2514, $2534, $252C, $251C, $2500, $253C, $255E, $255F,
$255A, $2554, $2569, $2566, $2560, $2550, $256C, $2567,
$2568, $2564, $2565, $2559, $2558, $2552, $2553, $256B,
$256A, $2518, $250C, $2588, $2584, $258C, $2590, $2580,
$03B1, $00DF, $0393, $03C0, $03A3, $03C3, $03BC, $03C4,
$03A6, $0398, $03A9, $03B4, $221E, $03C6, $03B5, $2229,
$2261, $00B1, $2265, $2264, $2320, $2321, $00F7, $2248,
$00B0, $2219, $00B7, $221A, $207F, $00B2, $25A0, $00A0);
*)
Detected encoding: ASCII (7 bit) | 2
|