/// <summary>
/// Constructor.
/// </summary>
/// <param name="syncLock">The thread synchronization object.</param>
/// <param name="mode">The log's current <see cref="OperationLogMode" />.</param>
internal MemoryOperationLog(object syncLock, OperationLogMode mode)
{
this.syncLock = syncLock;
this.isOpen = true;
this.mode = mode;
this.operations = new List <IOperation>();
}
private OperationLogMode mode; // The current mode
/// <summary>
/// Opens or creates a file operation log file.
/// </summary>
/// <param name="path">The path to the log file.</param>
/// <param name="transactionID">The log's transaction <see cref="Guid" />.</param>
/// <remarks>
/// New logs will be created in <see cref="OperationLogMode.Undo" /> mode.
/// </remarks>
public FileOperationLog(string path, Guid transactionID)
{
this.path = Path.GetFullPath(path);
this.file = new EnhancedFileStream(path, FileMode.OpenOrCreate, FileAccess.ReadWrite);
if (file.Length == 0)
{
// Initialize a new file
file.WriteInt32(Magic);
file.WriteInt32(0);
file.WriteInt32(0);
file.WriteInt32((int)OperationLogMode.Undo);
file.WriteBytesNoLen(transactionID.ToByteArray());
file.Flush();
}
else
{
// Open an existing file.
try
{
if (file.ReadInt32() != Magic || // Magic number
file.ReadInt32() != 0)
{ // Format Versopn
throw new Exception();
}
file.ReadInt32(); // Reserved
switch (file.ReadInt32()) // Mode
{
case (int)OperationLogMode.Undo:
mode = OperationLogMode.Undo;
break;
case (int)OperationLogMode.Redo:
mode = OperationLogMode.Redo;
break;
default:
throw new Exception();
}
this.transactionID = new Guid(file.ReadBytes(16));
if (transactionID != this.transactionID)
{
throw new Exception();
}
}
catch
{
throw new TransactionException(CorruptMsg);
}
}
}
