smscodec.pas

This source code in Delphi 7.0. Have function to decoding and encoding PDU format to ASCII and from

{ ---------------------------------------------------------      }
{ Purposes :                                                     }
{      1. Convert ASCII to 7-bit PDU                             }
{      2. Convert 7-bit, 8-bit and 16-bit PDU to ASCII           }
{      3. Decode/Parsing the hexadecimal (PDU) of SMS message    }
{      4. Encode ASCII characters to be sent as SMS ready string }
{                                                                }
{ ---------------------------------------------------------      }
{ Coder   : Daniel Eka Nugraha                                   }
{ URL     : http://www.averagecoder.com/                         }
{ Email   : [e-mail]                                     }
{ ---------------------------------------------------------      }
{ This is not a perfect one, so Use it at your own risk !        }
{ ---------------------------------------------------------      }

unit SMSCODEC;

interface

uses
  Windows, Messages, SysUtils, Classes, StrUtils, Math, Dialogs;

type
  TSMSCODEC = class(TComponent)
  private
    { Private declarations }
  protected
    { Protected declarations }
  public
    constructor Create(AOwner: TComponent); override;
    destructor Destroy; override;
    function Binerkan(Angka: integer): string;
    function Bin2Long(StrBiner: string): integer;
    function PDU7BIT2ASCII(StrPDU: string; PanjangUDH, PanjangData: integer): string;
    function PDU8BIT2ASCII(StrPDU: string; PanjangUDH, PanjangData: integer): string;
    function PDU16BIT2ASCII(StrPDU: string; PanjangUDH, PanjangData: integer): string;
    function ASCII2PDU7BIT(StrASCII: string): string;
    function DecodeSMS(StrSMS : string) : TStringList;
    function EncodeSMS(StrTujuan, StrPesan: string): string;
  published
    { Published declarations }
  end;

procedure Register;

implementation

var Nono: integer;
    EQ7BIT2ASCII : array [0..127] of integer;  // Table persamaan 7-bit ke ASCII
    EQASCII27BIT : array [0..255] of integer;  // Table persamaan ASCII ke 7-bit

procedure Register;
begin
  RegisterComponents('averagecoder', [TSMSCODEC]);
end;

constructor TSMSCODEC.Create(AOwner: TComponent);
var i : integer;
begin
   inherited Create(AOwner);

   // This is the transition table from 7-bit to ASCII

   Nono := -1;

   EQ7BIT2ASCII[0]  := 64;
   EQ7BIT2ASCII[1]  := 163;
   EQ7BIT2ASCII[2]  := 36;
   EQ7BIT2ASCII[3]  := 165;
   EQ7BIT2ASCII[4]  := 232;
   EQ7BIT2ASCII[5]  := 223;
   EQ7BIT2ASCII[6]  := 249;
   EQ7BIT2ASCII[7]  := 236;
   EQ7BIT2ASCII[8]  := 242;
   EQ7BIT2ASCII[9]  := 199;
   EQ7BIT2ASCII[10] := 10;
   EQ7BIT2ASCII[11] := 216;
   EQ7BIT2ASCII[12] := 248;
   EQ7BIT2ASCII[13] := 13;
   EQ7BIT2ASCII[14] := 197;
   EQ7BIT2ASCII[15] := 229;
   EQ7BIT2ASCII[16] := Nono;
   EQ7BIT2ASCII[17] := 95;
   EQ7BIT2ASCII[18] := Nono;
   EQ7BIT2ASCII[19] := Nono;
   EQ7BIT2ASCII[20] := Nono;
   EQ7BIT2ASCII[21] := Nono;
   EQ7BIT2ASCII[22] := Nono;
   EQ7BIT2ASCII[23] := Nono;
   EQ7BIT2ASCII[24] := Nono;
   EQ7BIT2ASCII[25] := Nono;
   EQ7BIT2ASCII[26] := Nono;
   EQ7BIT2ASCII[27] := Nono;
   EQ7BIT2ASCII[28] := 198;
   EQ7BIT2ASCII[29] := 230;
   EQ7BIT2ASCII[30] := 223;
   EQ7BIT2ASCII[31] := 201;
   EQ7BIT2ASCII[32] := 32;
   EQ7BIT2ASCII[33] := 33;
   EQ7BIT2ASCII[34] := 34;
   EQ7BIT2ASCII[35] := 35;
   EQ7BIT2ASCII[36] := 164;
   EQ7BIT2ASCII[37] := 37;
   EQ7BIT2ASCII[38] := 38;
   EQ7BIT2ASCII[39] := 39;
   EQ7BIT2ASCII[40] := 40;
   EQ7BIT2ASCII[41] := 41;
   EQ7BIT2ASCII[42] := 42;
   EQ7BIT2ASCII[43] := 43;
   EQ7BIT2ASCII[44] := 44;
   EQ7BIT2ASCII[45] := 45;
   EQ7BIT2ASCII[46] := 46;
   EQ7BIT2ASCII[47] := 47;
   EQ7BIT2ASCII[48] := 48;
   EQ7BIT2ASCII[49] := 49;
   EQ7BIT2ASCII[50] := 50;
   EQ7BIT2ASCII[51] := 51;
   EQ7BIT2ASCII[52] := 52;
   EQ7BIT2ASCII[53] := 53;
   EQ7BIT2ASCII[54] := 54;
   EQ7BIT2ASCII[55] := 55;
   EQ7BIT2ASCII[56] := 56;
   EQ7BIT2ASCII[57] := 57;
   EQ7BIT2ASCII[58] := 58;
   EQ7BIT2ASCII[59] := 59;
   EQ7BIT2ASCII[60] := 60;
   EQ7BIT2ASCII[61] := 61;
   EQ7BIT2ASCII[62] := 62;
   EQ7BIT2ASCII[63] := 63;
   EQ7BIT2ASCII[64] := 161;
   EQ7BIT2ASCII[65] := 65;
   EQ7BIT2ASCII[66] := 66;
   EQ7BIT2ASCII[67] := 67;
   EQ7BIT2ASCII[68] := 68;
   EQ7BIT2ASCII[69] := 69;
   EQ7BIT2ASCII[70] := 70;
   EQ7BIT2ASCII[71] := 71;
   EQ7BIT2ASCII[72] := 72;
   EQ7BIT2ASCII[73] := 73;
   EQ7BIT2ASCII[74] := 74;
   EQ7BIT2ASCII[75] := 75;
   EQ7BIT2ASCII[76] := 76;
   EQ7BIT2ASCII[77] := 77;
   EQ7BIT2ASCII[78] := 78;
   EQ7BIT2ASCII[79] := 79;
   EQ7BIT2ASCII[80] := 80;
   EQ7BIT2ASCII[81] := 81;
   EQ7BIT2ASCII[82] := 82;
   EQ7BIT2ASCII[83] := 83;
   EQ7BIT2ASCII[84] := 84;
   EQ7BIT2ASCII[85] := 85;
   EQ7BIT2ASCII[86] := 86;
   EQ7BIT2ASCII[87] := 87;
   EQ7BIT2ASCII[88] := 88;
   EQ7BIT2ASCII[89] := 89;
   EQ7BIT2ASCII[90] := 90;
   EQ7BIT2ASCII[91] := 196;
   EQ7BIT2ASCII[92] := 204;
   EQ7BIT2ASCII[93] := 209;
   EQ7BIT2ASCII[94] := 220;
   EQ7BIT2ASCII[95] := 167;
   EQ7BIT2ASCII[96] := 191;
   EQ7BIT2ASCII[97] := 97;
   EQ7BIT2ASCII[98] := 98;
   EQ7BIT2ASCII[99] := 99;
   EQ7BIT2ASCII[100] := 100;
   EQ7BIT2ASCII[101] := 101;
   EQ7BIT2ASCII[102] := 102;
   EQ7BIT2ASCII[103] := 103;
   EQ7BIT2ASCII[104] := 104;
   EQ7BIT2ASCII[105] := 105;
   EQ7BIT2ASCII[106] := 106;
   EQ7BIT2ASCII[107] := 107;
   EQ7BIT2ASCII[108] := 108;
   EQ7BIT2ASCII[109] := 109;
   EQ7BIT2ASCII[110] := 110;
   EQ7BIT2ASCII[111] := 111;
   EQ7BIT2ASCII[112] := 112;
   EQ7BIT2ASCII[113] := 113;
   EQ7BIT2ASCII[114] := 114;
   EQ7BIT2ASCII[115] := 115;
   EQ7BIT2ASCII[116] := 116;
   EQ7BIT2ASCII[117] := 117;
   EQ7BIT2ASCII[118] := 118;
   EQ7BIT2ASCII[119] := 119;
   EQ7BIT2ASCII[120] := 120;
   EQ7BIT2ASCII[121] := 121;
   EQ7BIT2ASCII[122] := 122;
   EQ7BIT2ASCII[123] := 228;
   EQ7BIT2ASCII[124] := 246;
   EQ7BIT2ASCII[125] := 241;
   EQ7BIT2ASCII[126] := 252;
   EQ7BIT2ASCII[127] := 224;

   // This is the transition table from ASCII to 7-BIT; index reversing :)

   for i := 0 to High(EQ7BIT2ASCII) do
   begin
       if EQ7BIT2ASCII[i] <> Nono then
          EQASCII27BIT[EQ7BIT2ASCII[i]] := i;
   end;
end; { TSMSCODEC.Create }


destructor TSMSCODEC.Destroy;
begin
  inherited Destroy;
end; { TSMSCODEC.Destroy }



{

--------------------------------------------------------------------------------
  function Binerkan

  -> Convert integer to binary
  
  -> parameters:
     Angka: integer; -> the integer value

  -> Return value: string of 1 and 0 (nothing genius at all :D)
--------------------------------------------------------------------------------

}

function TSMSCODEC.Binerkan(Angka : integer): string;
var i : Integer;
    hasil : array [0..7] of Integer;
    SISA : array [0..7] of Integer;
    StrHasil : string;
begin
    result := '';

    if angka > 1 Then
    begin
        i := 1;
        repeat
            hasil[i] := Trunc(angka / 2);
            SISA[i] := angka mod 2;
            angka := hasil[i];
            i := i + 1;
            StrHasil := IntToStr(SISA[i - 1]) + StrHasil;
        until hasil[i - 1] < 2;
        StrHasil := IntToStr(hasil[i - 1]) + StrHasil;
    end
    else if angka = 1 then
        StrHasil := '00000001'
    else if angka = 0 Then
        StrHasil := '00000000';

    for i := 1 to (8 - Length(StrHasil)) do
        StrHasil := '0' + StrHasil;

    result := StrHasil;
end;  { TSMSCODEC.Binerkan }


{

--------------------------------------------------------------------------------
  function Bin2Long

  -> Convert binaty string to integer
  -> Parameter: 
     StrBiner: string; -> the binary string;

  -> Return value: integer;
--------------------------------------------------------------------------------

}

function TSMSCODEC.Bin2Long(StrBiner : string): integer;
var i, x : integer;
begin
    x := 0;
    for i := 1 to Length(StrBiner) do
    begin
       x := x + StrToInt(Copy(StrBiner, i, 1)) * Trunc(Power(2,(Length(StrBiner) - i)));
    end;
    result := x;
end; { TSMSCODEC.Bin2Long }



{

--------------------------------------------------------------------------------
  function PDU7BIT2ASCII

  -> Convert PDU (string 7-bit PDU) to ASCII
  -> Parameter:
     StrPDU: string -> the PDUString
     PanjangUDH: integer; -> the length of the UDH
     PanjangData: integer; -> the length of the data

  -> return value: ASCII string
--------------------------------------------------------------------------------

}

function TSMSCODEC.PDU7BIT2ASCII(StrPDU : string; PanjangUDH, PanjangData: integer) : string;
var i,j,x,z : integer;
    y, StrASCII : string;
    ArrPDU   : array of string;
    Arr7Bit  : array of string;
    ArrASCII : array of string;
begin
    j := 1;
    z := 0;

    // 2 PDU chars represent 1 ASCII chars, so the length of the
    // ASCII chars sequence is 1/2 of the string PDU length
    SetLength(ArrPDU,Length(StrPDU) div 2);

    // Load each pair of PDU string to the appropriate index of ArrPDU
    while j < Length(StrPDU) do
    begin
       ArrPDU[z] := '$' + Copy(StrPDU,j,2); // '$' + string = hexadecimal
       j := j + 2;
       Inc(z);
    end;

    // Convert each ArrPDU item to binary for decoding
    for i := 0 to High(ArrPDU) do
    begin
        y := ArrPDU[i];   
        ArrPDU[i] := '';  
        ArrPDU[i] := Binerkan(StrToInt(y));
    end;

    x := 0;

    SetLength(Arr7BIT,x+1);

    // The core process - the bit mutation
    for i := 0 to High(ArrPDU) do
    begin
        if i mod 7 = 0 then
        begin
           Arr7BIT[x] := RightStr(ArrPDU[i],7);
        end
        else
        begin
           if i mod 7 = 6 then
           begin
              Arr7BIT[x] := RightStr(ArrPDU[i],1) + LeftStr(ArrPDU[i-1],6);
              x := x + 1;
              SetLength(Arr7BIT,x+1);
              Arr7BIT[x] := LeftStr(ArrPDU[i],7);
           end
           else
              Arr7BIT[x] := RightStr(ArrPDU[i],Length(ArrPDU[i])-(i mod 7)-1) + LeftStr(ArrPDU[i-1],i mod 7);
        end;
        x := x + 1;
        SetLength(Arr7BIT,x+1);
    end; { for }

    j := 0;

    while j <= High(Arr7BIT) do
    begin
        SetLength(ArrASCII,Length(ArrASCII)+1);

        if Bin2Long(Arr7BIT[j]) = 27 then
        begin
           inc(j);
           case Bin2Long(Arr7BIT[j]) of
                10 : ArrASCII[High(ArrASCII)] := Chr(12);
                20 : ArrASCII[High(ArrASCII)] := Chr(94);
                40 : ArrASCII[High(ArrASCII)] := Chr(123);
                41 : ArrASCII[High(ArrASCII)] := Chr(125);
                47 : ArrASCII[High(ArrASCII)] := Chr(92);
                60 : ArrASCII[High(ArrASCII)] := Chr(91);
                61 : ArrASCII[High(ArrASCII)] := Chr(126);
                62 : ArrASCII[High(ArrASCII)] := Chr(93);
                64 : ArrASCII[High(ArrASCII)] := Chr(124);
           else
                ArrASCII[High(ArrASCII)] := Chr(0);
           end;
        end
        else
        begin
           ArrASCII[High(ArrASCII)] := Chr(EQ7BIT2ASCII[Bin2Long(Arr7BIT[j])]);
        end;
        Inc(j);
    end; { while }

    SetLength(ArrASCII,PanjangData);

    for i := 0 to High(ArrASCII) do
        StrASCII := StrASCII + (ArrASCII[i]); 

    ArrPDU   := nil; Arr7Bit  := nil; ArrASCII := nil;

    // if no UDH, ignore the octet info of UDH length,