{ TBinaryRxDatapacketReader implementation See the file COPYING.FPC, included in this distribution, for details about the copyright. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. **********************************************************************} unit ex_rx_bin_datapacket; {$mode objfpc}{$H+} interface uses Classes, SysUtils, dom, db, ex_rx_datapacket; type TChangeLogEntry = record UpdateKind : TUpdateKind; OrigEntry : integer; NewEntry : integer; end; TChangeLogEntryArr = array of TChangeLogEntry; type { TBinaryRxDatapacketReader } TBinaryRxDatapacketReader = class(TRxDataPacketReader) public procedure LoadFieldDefs(AFieldDefs : TFieldDefs); override; procedure StoreFieldDefs(AFieldDefs : TFieldDefs); override; function GetRecordRowState(out AUpdOrder : Integer) : TRowState; override; procedure FinalizeStoreRecords; override; function GetCurrentRecord : boolean; override; procedure GotoNextRecord; override; procedure InitLoadRecords; override; procedure RestoreRecord(ADataset : TDataset); override; procedure StoreRecord(ADataset : TDataset; ARowState : TRowState; AUpdOrder : integer = 0); override; class function RecognizeStream(AStream : TStream) : boolean; override; end; implementation uses dbconst; { TBinaryRxDatapacketReader } const RxBinaryIdent = 'BinRxDataset'; procedure TBinaryRxDatapacketReader.LoadFieldDefs(AFieldDefs: TFieldDefs); var FldCount : word; i : integer; begin if not RecognizeStream(Stream) then DatabaseError(SStreamNotRecognised); FldCount:=Stream.ReadWord; AFieldDefs.Clear; for i := 0 to FldCount -1 do with TFieldDef.create(AFieldDefs) do begin Name := Stream.ReadAnsiString; Displayname := Stream.ReadAnsiString; Size := Stream.ReadWord; DataType := TFieldType(Stream.ReadWord); if Stream.ReadByte = 1 then Attributes := Attributes + [faReadonly]; end; end; procedure TBinaryRxDatapacketReader.StoreFieldDefs(AFieldDefs: TFieldDefs); var i : integer; begin Stream.Write(RxBinaryIdent[1],length(RxBinaryIdent)); Stream.WriteWord(AFieldDefs.Count); for i := 0 to AFieldDefs.Count -1 do with AFieldDefs[i] do begin Stream.WriteAnsiString(Name); Stream.WriteAnsiString(DisplayName); Stream.WriteWord(size); Stream.WriteWord(ord(DataType)); if faReadonly in Attributes then Stream.WriteByte(1) else Stream.WriteByte(0); end; end; function TBinaryRxDatapacketReader.GetRecordRowState(out AUpdOrder: Integer ): TRowState; var Buf : byte; begin Buf := 0; AUpdOrder := 0; Stream.Read(Buf,1); Result := ByteToRowState(Buf); if Result<>[] then Stream.ReadBuffer(AUpdOrder,sizeof(integer)); end; procedure TBinaryRxDatapacketReader.FinalizeStoreRecords; begin // Do nothing end; function TBinaryRxDatapacketReader.GetCurrentRecord: boolean; var Buf : byte; begin Buf := 0; Result := (Stream.Read(Buf,1)=1) and (Buf=$fe); end; procedure TBinaryRxDatapacketReader.GotoNextRecord; begin // Do Nothing end; procedure TBinaryRxDatapacketReader.InitLoadRecords; begin // Do Nothing end; procedure TBinaryRxDatapacketReader.RestoreRecord(ADataset: TDataset); begin Stream.ReadBuffer(ADataset.ActiveBuffer^,ADataset.RecordSize); end; procedure TBinaryRxDatapacketReader.StoreRecord(ADataset: TDataset; ARowState: TRowState; AUpdOrder: integer); begin Stream.WriteByte($fe); Stream.WriteByte(RowStateToByte(ARowState)); if ARowState<>[] then Stream.WriteBuffer(AUpdOrder,sizeof(integer)); Stream.WriteBuffer(ADataset.ActiveBuffer^,ADataset.RecordSize); end; class function TBinaryRxDatapacketReader.RecognizeStream(AStream: TStream ): boolean; var s : string; len : integer; begin Len := length(RxBinaryIdent); setlength(s,len); if (AStream.Read (s[1],len) = len) and (s=RxBinaryIdent) then Result := True else Result := False; end; initialization RegisterDatapacketReader(TBinaryRxDatapacketReader,dfBinary); end.