16 and 32 bit CRC

Pascal CRC in 32 and 16 bits

Contributor: FLOOR A.C. NAAIJKENS

{
Author: FLOOR A.C. NAAIJKENS

Part of The ECO Library II:
}

Unit Eco_CRC;

Interface

Function __CRC32(Value: Byte; CRC : LongInt) : LongInt;
Function __CRC16(Value: Byte; CRC : Word) : Word;

Implementation

Function __crc32(value: Byte; crc: LongInt): LongInt;
Const
  crc32_table : Array[0..255] of LongInt = (
    $00000000, $77073096, $ee0e612c, $990951ba, $076dc419, $706af48f,
    $e963a535, $9e6495a3, $0edb8832, $79dcb8a4, $e0d5e91e, $97d2d988,
    $09b64c2b, $7eb17cbd, $e7b82d07, $90bf1d91, $1db71064, $6ab020f2,
    $f3b97148, $84be41de, $1adad47d, $6ddde4eb, $f4d4b551, $83d385c7,
    $136c9856, $646ba8c0, $fd62f97a, $8a65c9ec, $14015c4f, $63066cd9,
    $fa0f3d63, $8d080df5, $3b6e20c8, $4c69105e, $d56041e4, $a2677172,
    $3c03e4d1, $4b04d447, $d20d85fd, $a50ab56b, $35b5a8fa, $42b2986c,
    $dbbbc9d6, $acbcf940, $32d86ce3, $45df5c75, $dcd60dcf, $abd13d59,
    $26d930ac, $51de003a, $c8d75180, $bfd06116, $21b4f4b5, $56b3c423,
    $cfba9599, $b8bda50f, $2802b89e, $5f058808, $c60cd9b2, $b10be924,
    $2f6f7c87, $58684c11, $c1611dab, $b6662d3d, $76dc4190, $01db7106,
    $98d220bc, $efd5102a, $71b18589, $06b6b51f, $9fbfe4a5, $e8b8d433,
    $7807c9a2, $0f00f934, $9609a88e, $e10e9818, $7f6a0dbb, $086d3d2d,
    $91646c97, $e6635c01, $6b6b51f4, $1c6c6162, $856530d8, $f262004e,
    $6c0695ed, $1b01a57b, $8208f4c1, $f50fc457, $65b0d9c6, $12b7e950,
    $8bbeb8ea, $fcb9887c, $62dd1ddf, $15da2d49, $8cd37cf3, $fbd44c65,
    $4db26158, $3ab551ce, $a3bc0074, $d4bb30e2, $4adfa541, $3dd895d7,
    $a4d1c46d, $d3d6f4fb, $4369e96a, $346ed9fc, $ad678846, $da60b8d0,
    $44042d73, $33031de5, $aa0a4c5f, $dd0d7cc9, $5005713c, $270241aa,
    $be0b1010, $c90c2086, $5768b525, $206f85b3, $b966d409, $ce61e49f,
    $5edef90e, $29d9c998, $b0d09822, $c7d7a8b4, $59b33d17, $2eb40d81,
    $b7bd5c3b, $c0ba6cad, $edb88320, $9abfb3b6, $03b6e20c, $74b1d29a,
    $ead54739, $9dd277af, $04db2615, $73dc1683, $e3630b12, $94643b84,
    $0d6d6a3e, $7a6a5aa8, $e40ecf0b, $9309ff9d, $0a00ae27, $7d079eb1,
    $f00f9344, $8708a3d2, $1e01f268, $6906c2fe, $f762575d, $806567cb,
    $196c3671, $6e6b06e7, $fed41b76, $89d32be0, $10da7a5a, $67dd4acc,
    $f9b9df6f, $8ebeeff9, $17b7be43, $60b08ed5, $d6d6a3e8, $a1d1937e,
    $38d8c2c4, $4fdff252, $d1bb67f1, $a6bc5767, $3fb506dd, $48b2364b,
    $d80d2bda, $af0a1b4c, $36034af6, $41047a60, $df60efc3, $a867df55,
    $316e8eef, $4669be79, $cb61b38c, $bc66831a, $256fd2a0, $5268e236,
    $cc0c7795, $bb0b4703, $220216b9, $5505262f, $c5ba3bbe, $b2bd0b28,
    $2bb45a92, $5cb36a04, $c2d7ffa7, $b5d0cf31, $2cd99e8b, $5bdeae1d,
    $9b64c2b0, $ec63f226, $756aa39c, $026d930a, $9c0906a9, $eb0e363f,
    $72076785, $05005713, $95bf4a82, $e2b87a14, $7bb12bae, $0cb61b38,
    $92d28e9b, $e5d5be0d, $7cdcefb7, $0bdbdf21, $86d3d2d4, $f1d4e242,
    $68ddb3f8, $1fda836e, $81be16cd, $f6b9265b, $6fb077e1, $18b74777,
    $88085ae6, $ff0f6a70, $66063bca, $11010b5c, $8f659eff, $f862ae69,
    $616bffd3, $166ccf45, $a00ae278, $d70dd2ee, $4e048354, $3903b3c2,
    $a7672661, $d06016f7, $4969474d, $3e6e77db, $aed16a4a, $d9d65adc,
    $40df0b66, $37d83bf0, $a9bcae53, $debb9ec5, $47b2cf7f, $30b5ffe9,
    $bdbdf21c, $cabac28a, $53b39330, $24b4a3a6, $bad03605, $cdd70693,
    $54de5729, $23d967bf, $b3667a2e, $c4614ab8, $5d681b02, $2a6f2b94,
    $b40bbe37, $c30c8ea1, $5a05df1b, $2d02ef8d
  );

begin
  if crc = 0 then
    crc := $ffffffff; { must be set high to start With }
  __crc32 := crc32_table[Byte(crc xor LongInt(value))] xor
             ((crc shr 8) and $00ffffff);
end;

Function __crc16(value: Byte; crc: Word): Word;
Const
  crc16_table : Array[0..255] of Word = (
     $0000, $1021, $2042, $3063, $4084, $50a5, $60c6, $70e7,
     $8108, $9129, $a14a, $b16b, $c18c, $d1ad, $e1ce, $f1ef,
     $1231, $0210, $3273, $2252, $52b5, $4294, $72f7, $62d6,
     $9339, $8318, $b37b, $a35a, $d3bd, $c39c, $f3ff, $e3de,
     $2462, $3443, $0420, $1401, $64e6, $74c7, $44a4, $5485,
     $a56a, $b54b, $8528, $9509, $e5ee, $f5cf, $c5ac, $d58d,
     $3653, $2672, $1611, $0630, $76d7, $66f6, $5695, $46b4,
     $b75b, $a77a, $9719, $8738, $f7df, $e7fe, $d79d, $c7bc,
     $48c4, $58e5, $6886, $78a7, $0840, $1861, $2802, $3823,
     $c9cc, $d9ed, $e98e, $f9af, $8948, $9969, $a90a, $b92b,
     $5af5, $4ad4, $7ab7, $6a96, $1a71, $0a50, $3a33, $2a12,
     $dbfd, $cbdc, $fbbf, $eb9e, $9b79, $8b58, $bb3b, $ab1a,
     $6ca6, $7c87, $4ce4, $5cc5, $2c22, $3c03, $0c60, $1c41,
     $edae, $fd8f, $cdec, $ddcd, $ad2a, $bd0b, $8d68, $9d49,
     $7e97, $6eb6, $5ed5, $4ef4, $3e13, $2e32, $1e51, $0e70,
     $ff9f, $efbe, $dfdd, $cffc, $bf1b, $af3a, $9f59, $8f78,
     $9188, $81a9, $b1ca, $a1eb, $d10c, $c12d, $f14e, $e16f,
     $1080, $00a1, $30c2, $20e3, $5004, $4025, $7046, $6067,
     $83b9, $9398, $a3fb, $b3da, $c33d, $d31c, $e37f, $f35e,
     $02b1, $1290, $22f3, $32d2, $4235, $5214, $6277, $7256,
     $b5ea, $a5cb, $95a8, $8589, $f56e, $e54f, $d52c, $c50d,
     $34e2, $24c3, $14a0, $0481, $7466, $6447, $5424, $4405,
     $a7db, $b7fa, $8799, $97b8, $e75f, $f77e, $c71d, $d73c,
     $26d3, $36f2, $0691, $16b0, $6657, $7676, $4615, $5634,
     $d94c, $c96d, $f90e, $e92f, $99c8, $89e9, $b98a, $a9ab,
     $5844, $4865, $7806, $6827, $18c0, $08e1, $3882, $28a3,
     $cb7d, $db5c, $eb3f, $fb1e, $8bf9, $9bd8, $abbb, $bb9a,


     $4a75, $5a54, $6a37, $7a16, $0af1, $1ad0, $2ab3, $3a92,
     $fd2e, $ed0f, $dd6c, $cd4d, $bdaa, $ad8b, $9de8, $8dc9,
     $7c26, $6c07, $5c64, $4c45, $3ca2, $2c83, $1ce0, $0cc1,
     $ef1f, $ff3e, $cf5d, $df7c, $af9b, $bfba, $8fd9, $9ff8,
     $6e17, $7e36, $4e55, $5e74, $2e93, $3eb2, $0ed1, $1ef0
   );

begin
  __crc16 := crc16_table[((crc shr 8) and 255)] xor
             (crc shl 8) xor value;
end;

end.

{==========================================================================}
{==========================================================================}
{==========================================================================}

CRC.PAS
{$M 65520, 0, 655360}
Uses
  Crt, Dos,
  eco_lib;

Var
  take32,
  take16 : Boolean;
  sourcepath,
  source : String;
  numFiles, i : Word;
  srec : SearchRec;
  filar : Array[1..1024] of ^SearchRec;

Function convert32(fname: String; fsize: LongInt; x1, x2, y: Byte): String;
Const
  bufsize = 32768;
Type
  fbuf = Array[1..bufsize] of Byte;
Var
  i : Word;
  source : File;
  bread : Word;
  Filebuf : ^fbuf;
  crc, tr : LongInt;
  nr : Real;

begin
  crc := $ffffffff;
  tr := 0;
  new(Filebuf);
  assign(source, fname);
  reset(source, 1);
  GotoXY(x1, y);
  Write(__rep(x2-x1-3, '°'));
  Write(' ', fname);
  Repeat
    blockread(source, Filebuf^, bufsize, bread);
    tr := tr + bread;
    nr := tr/fsize;
    nr := nr * (x2-x1-3);
    GotoXY(x1, y);
    Write(__rep(trunc(nr), 'Û'));
    For i := 1 to bread do
      crc := __crc32(Filebuf^[i], crc);
  Until (bread = 0);
  close(source);
  GotoXY(x1, y);
  dispose(Filebuf);
  Write(fname:12, ' ', fsize:7, ' Bytes. HEX-CRC/32: ',__tohexstr(crc, 4));
  clreol; convert32 := '';
end;

Function convert16(fname: String; fsize: LongInt; x1, x2, y: Byte): String;
Const
  bufsize = 32768;
Type
  fbuf = Array[1..bufsize] of Byte;
Var
  i : Word;
  source : File;
  bread : Word;
  Filebuf : ^fbuf;
  crc, tr : LongInt;
  nr : Real;

begin
  crc := $0000;
  tr := 0;
  new(Filebuf);
  assign(source, fname);
  reset(source, 1);
  GotoXY(x1, y);
  Write(__rep(x2-x1-3, '°'));
  Write(' ', fname);
  Repeat
    blockread(source, Filebuf^, bufsize, bread);
    tr := tr + bread;
    nr := tr/fsize;
    nr := nr * (x2-x1-3);
    GotoXY(x1, y);
    Write(__rep(trunc(nr), 'Û'));
    For i := 1 to bread do
      crc := __crc16(Filebuf^[i], crc);
  Until (bread = 0);
  close(source);
  GotoXY(x1, y);
  dispose(Filebuf);
  Write(fname:12, ' ', fsize:7, ' Bytes. HEX-CRC/16: ', __tohexstr(crc, 2));
  clreol;
  convert16 := '';
end;

Function convert16_32(fname:String; fsize: LongInt; x1, x2, y: Byte):String;
Const
  bufsize = 32768;
Type
  fbuf = Array[1..bufsize] of Byte;
Var
  i : Word;
  source : File;
  bread : Word;
  Filebuf : ^fbuf;
  crc,
  crc32,
  tr : LongInt;
  nr : Real;

begin
  crc := $0000;
  tr := 0;
  crc32 := $ffffffff;
  new(Filebuf);
  assign(source, fname);
  reset(source, 1);
  GotoXY(x1, y);
  Write(__rep(x2-x1-3, '°'));
  Write(' ', fname);
  Repeat
    blockread(source, Filebuf^, bufsize, bread);
    tr := tr + bread;
    nr := tr/fsize;
    nr := nr * (x2-x1-3);
    GotoXY(x1, y);
    Write(__rep(trunc(nr), 'Û'));
    For i := 1 to bread do begin
      crc := __crc16(Filebuf^[i], crc);
      crc32 := __crc32(Filebuf^[i], crc32);
    end;
  Until (bread = 0);
  close(source);
  GotoXY(x1, y);
  dispose(Filebuf);
  Write(fname:12, ' ', fsize:7,' Bytes. HEX-CRC/16: ', __tohexstr(crc, 2),
        ' 32: ', __tohexstr(crc32, 4));
  clreol;
  convert16_32 := '';
end;

{main}
begin
  source := fexpand(paramstr(1));
  take32 := False;
  take16 := False;
  if paramstr(2) = '/32' then
    take32 := True;
  if paramstr(2) = '/16' then
    take16 := True;
  numFiles := 0;
  findfirst(source, anyFile, srec);
  While Doserror=0 do
  begin
    if not (((srec.attr and directory) > 0) or ((srec.attr and volumeid) > 0)
             and (srec.size > 0)) then
    begin
      inc(numFiles);
      new(filar[numFiles]);
      filar[numFiles]^ := srec;
      filar[numFiles]^.name := __up(filar[numFiles]^.name);
    end; findnext(srec);
  end;
  Writeln(numFiles, ' File(s) found.');

  For i := 1 to numFiles do
    if take32 then
      Writeln(convert32(sourcepath + filar[i]^.name, filar[i]^.size,
              5, 35, WhereY))
      else
      if take16 then
        Writeln(convert16(sourcepath + filar[i]^.name, filar[i]^.size,
                5, 35, WhereY))
      else
        Writeln(convert16_32(sourcepath + filar[i]^.name, filar[i]^.size,
                5, 35, WhereY));
end.

 

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