; CONTINUE;
k:=start[Len];
nextCode:=k+weight[Len];
IF Len<=TableBits THEN
BEGIN
FOR i:=k TO PRED(nextCode) DO
Table^[i]:=ch;
END ELSE BEGIN
p:=Addr(Table^[word(k) SHR jutbits]);i:=Len-TableBits;
WHILE i<>0 DO BEGIN
IF p^[0]=0 THEN
BEGIN
right^[Avail]:=0;left^[Avail]:=0;p^[0]:=Avail;INC(Avail);
END;
IF (k AND mask)<>0 THEN
p:=addr(right^[p^[0]])
ELSE
p:=addr(left^[p^[0]]);
k:=k SHL 1;DEC(i);
END;
p^[0]:=ch;
END;
start[Len]:=nextCode;
END;
END;
PROCEDURE ReadPtLen(nn,nBit,ispecial:TwoByteInt);
VAR
i,c,n:TwoByteInt;
mask:Word;
BEGIN
n:=GetBits(nBit);
IF n=0 THEN
BEGIN
c:=GetBits(nBit);
FOR i:=0 TO PRED(nn) DO
PtLen[i]:=0;
FOR i:=0 TO 255 DO
PtTable[i]:=c;
END ELSE BEGIN
i:=0;
WHILE (i<n) DO BEGIN
c:=BitBuf SHR (BITBUFSIZ-3);
IF c=7 THEN
BEGIN
mask:=1 SHL (BITBUFSIZ-4);
WHILE (mask AND BitBuf)<>0 DO BEGIN
mask:=mask SHR 1;INC(c);
END;
END;
IF c<7 THEN
FillBuf(3)
ELSE
FillBuf(c-3);
PtLen[i]:=c;INC(i);
IF i=ispecial THEN
BEGIN
c:=PRED(TwoByteInt(GetBits(2)));
WHILE c>=0 DO BEGIN
PtLen[i]:=0;INC(i);DEC(c);
END;
END;
END;
WHILE i<nn DO BEGIN
PtLen[i]:=0;INC(i);
END;
MakeTable(nn,@PtLen,8,@PtTable);
END;
END;
PROCEDURE ReadCLen;
VAR
i,c,n:TwoByteInt;
mask:Word;
BEGIN
n:=GetBits(CBIT);
IF n=0 THEN
BEGIN
c:=GetBits(CBIT);
FOR i:=0 TO PRED(NC) DO
CLen^[i]:=0;
FOR i:=0 TO 4095 DO
CTable^[i]:=c;
END ELSE BEGIN
i:=0;
WHILE i<n DO BEGIN
c:=PtTable[BitBuf SHR (BITBUFSIZ-8)];
IF c>=NT THEN
BEGIN
mask:=1 SHL (BITBUFSIZ-9);
REPEAT
IF (BitBuf AND mask)<>0 THEN
c:=right^[c]
ELSE
c:=left^[c];
mask:=mask SHR 1;
UNTIL c<NT;
END;
FillBuf(PtLen[c]);
IF c<=2 THEN
BEGIN
IF c=1 THEN
c:=2+GetBits(4)
ELSE
IF c=2 THEN
c:=19+GetBits(CBIT);
WHILE c>=0 DO BEGIN
CLen^[i]:=0;INC(i);DEC(c);
END;
END ELSE BEGIN
CLen^[i]:=c-2;INC(i);
END;
END;
WHILE i<NC DO BEGIN
CLen^[i]:=0;INC(i);
END;
MakeTable(NC,PByte(CLen),12,PWord(CTable));
END;
END;
FUNCTION DecodeC:Word;
VAR
j,mask:Word;
BEGIN
IF BlockSize=0 THEN
BEGIN
BlockSize:=GetBits(16);
ReadPtLen(NT,TBIT,3);
ReadCLen;
ReadPtLen(NP,PBIT,-1);
END;
DEC(BlockSize);
j:=CTable^[BitBuf SHR (BITBUFSIZ-12)];
IF j>=NC THEN
BEGIN
mask:=1 SHL (BITBUFSIZ-13);
REPEAT
IF (BitBuf AND mask)<>0 THEN
j:=right^[j]
ELSE
j:=left^[j];
mask:=mask SHR 1;
UNTIL j<NC;
END;
FillBuf(CLen^[j]);
DecodeC:=j;
END;
FUNCTION DecodeP:Word;
VAR
j,mask:Word;
BEGIN
j:=PtTable[BitBuf SHR (BITBUFSIZ-8)];
IF j>=NP THEN
BEGIN
mask:=1 SHL (BITBUFSIZ-9);
REPEAT
IF (BitBuf AND mask)<>0 THEN
j:=right^[j]
ELSE
j:=left^[j];
mask:=mask SHR 1;
UNTIL j<NP;
END;
FillBuf(PtLen[j]);
IF j<>0 THEN
BEGIN
DEC(j);j:=(1 SHL j)+GetBits(j);
END;
DecodeP:=j;
END;
{declared as static vars}
VAR
decode_i:Word;
decode_j:TwoByteInt;
PROCEDURE DecodeBuffer(count:Word;Buffer:PByte);
VAR
c,r:Word;
BEGIN
r:=0;DEC(decode_j);
WHILE (decode_j>=0) DO BEGIN
Buffer^[r]:=Buffer^[decode_i];decode_i:=SUCC(decode_i) AND PRED(DICSIZ);
INC(r);
IF r=count THEN
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