public void CreateCRCFile(string fileName, CarsonBackend database, List <string> dataFields, FileStream readStream, BinaryReader reader, TableInstance tableInstance, bool headerOnly)
{
List <Definition> fieldDefinitions = new List <Definition>();
for (int x = 0; x < dataFields.Count; x++)
{
Definition definition = database.FindFieldDefinition(dataFields[x]);
if (definition == null)
{
throw new Exception("Invalid Field Name: " + dataFields[x]);
}
fieldDefinitions.Add(definition);
}
if (File.Exists(fileName))
{
File.Delete(fileName);
}
using (FileStream writeStream = new FileStream(fileName, FileMode.Create, FileAccess.Write, FileShare.None))
using (BinaryWriter writer = new BinaryWriter(writeStream))
{
writeStream.Seek(0, SeekOrigin.Begin);
writer.Write(StringToByte("CARSONDB" + CarsonBackend.DatabaseVersion));
List <int> fieldOffsets = new List <int>();
string fieldDefinitionString = database.DatabaseName + "\0";
for (int x = 0; x < fieldDefinitions.Count; x++)
{
fieldDefinitionString += fieldDefinitions[x].FieldName + (x < fieldDefinitions.Count - 1 ? "\0" : "");
fieldOffsets.Add(Convert.ToInt32(fieldDefinitions[x].FieldOrdinal));
fieldOffsets.Add(ComputeFieldSize(fieldDefinitions[x].FieldType));
fieldOffsets.Add(fieldDefinitions[x].FieldType == AVImarkDataType.AVImarkDynamicString ? 1 : 0);
}
writer.Write(fieldDefinitionString);
int[] fieldData = fieldOffsets.ToArray();
if (!headerOnly)
{
using (CarsonLibDll carsonLib = new CarsonLibDll())
{
carsonLib.ComputerCompareCrc(readStream.SafeFileHandle, writeStream.SafeFileHandle, (int)tableInstance, ref fieldData[0], fieldDefinitions.Count, CrcFunction.Create, (int)writeStream.Position, database.IsClassic());
}
}
}
}
public List <int> FindChangedRecords(string fileName, CarsonBackend database, FileStream readStream, out int recordsFound, TableInstance tableInstance)
{
using (FileStream diffStream = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.None))
using (BinaryReader diffReader = new BinaryReader(diffStream))
{
IntPtr recordPtr;
List <Definition> fieldDefinitions = new List <Definition>();
ValidateFileHeader(diffStream, diffReader);
string fieldDefinitionString = diffReader.ReadString();
string[] fields = fieldDefinitionString.Split('\0');
for (int x = 1; x < fields.Length; x++)
{
fieldDefinitions.Add(database.FindFieldDefinition(fields[x]));
}
List <int> fieldOffsets = new List <int>();
for (int x = 0; x < fieldDefinitions.Count; x++)
{
fieldOffsets.Add(Convert.ToInt32(fieldDefinitions[x].FieldOrdinal));
fieldOffsets.Add(ComputeFieldSize(fieldDefinitions[x].FieldType));
fieldOffsets.Add(fieldDefinitions[x].FieldType == AVImarkDataType.AVImarkDynamicString ? 1 : 0);
}
int[] fieldData = fieldOffsets.ToArray();
using (CarsonLibDll carsonLib = new CarsonLibDll())
{
recordPtr = carsonLib.ComputerCompareCrc(readStream.SafeFileHandle, diffStream.SafeFileHandle, (int)tableInstance, ref fieldData[0], fieldDefinitions.Count, CrcFunction.Compare, (int)diffStream.Position, database.IsClassic());
int recordCount = carsonLib.RecordCountFromHandle(recordPtr);
int[] result = new int[recordCount];
Marshal.Copy(recordPtr, result, 0, recordCount);
//Number of records in differential file is calculated on the file length less 16 (diff file header + version) and the field definitions.
recordsFound = ((int)diffStream.Length - 16 - fieldDefinitionString.Length) / 4;
return(new List <int>(result));
}
}
}