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CRC stuff moved to CRC unit

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pierre 2000-05-15 13:19:04 +00:00
parent 1b45cfb51b
commit f63815853e
1 changed files with 7 additions and 79 deletions
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86
compiler/ppu.pas
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@ -251,86 +251,11 @@ type
implementation
{$ifdef Test_Double_checksum}
uses
comphook;
{$ifdef Test_Double_checksum}
comphook,
{$endif def Test_Double_checksum}
{*****************************************************************************
Crc 32
*****************************************************************************}
var
Crc32Tbl : array[0..255] of longint;
procedure MakeCRC32Tbl;
var
crc : longint;
i,n : byte;
begin
for i:=0 to 255 do
begin
crc:=i;
for n:=1 to 8 do
if odd(crc) then
crc:=(crc shr 1) xor longint($edb88320)
else
crc:=crc shr 1;
Crc32Tbl[i]:=crc;
end;
end;
{$ifopt R+}
{$define Range_check_on}
{$endif opt R+}
{$R- needed here }
{CRC 32}
Function Crc32(Const HStr:String):longint;
var
i,InitCrc : longint;
begin
if Crc32Tbl[1]=0 then
MakeCrc32Tbl;
InitCrc:=longint($ffffffff);
for i:=1to Length(Hstr) do
InitCrc:=Crc32Tbl[byte(InitCrc) xor ord(Hstr[i])] xor (InitCrc shr 8);
Crc32:=InitCrc;
end;
Function UpdateCrc32(InitCrc:longint;var InBuf;InLen:Longint):longint;
var
i : word;
p : pchar;
begin
if Crc32Tbl[1]=0 then
MakeCrc32Tbl;
p:=@InBuf;
for i:=1 to InLen do
begin
InitCrc:=Crc32Tbl[byte(InitCrc) xor byte(p^)] xor (InitCrc shr 8);
inc(longint(p));
end;
UpdateCrc32:=InitCrc;
end;
Function UpdCrc32(InitCrc:longint;b:byte):longint;
begin
if Crc32Tbl[1]=0 then
MakeCrc32Tbl;
UpdCrc32:=Crc32Tbl[byte(InitCrc) xor b] xor (InitCrc shr 8);
end;
{$ifdef Range_check_on}
{$R+}
{$undef Range_check_on}
{$endif Range_check_on}
crc;
{*****************************************************************************
TPPUFile
@ -998,7 +923,10 @@ end;
end.
{
$Log$
Revision 1.58 2000-05-12 08:58:51 pierre
Revision 1.59 2000-05-15 13:19:04 pierre
CRC stuff moved to CRC unit
Revision 1.58 2000/05/12 08:58:51 pierre
* adapted to Delphi 3
Revision 1.57 2000/05/11 06:54:29 florian