private PrepareLogRecord GetPrepareInternal(ITransactionFileReader reader, long pos)
{
var result = reader.TryReadAt(pos);
if (!result.Success)
{
throw new InvalidOperationException("Couldn't read record which is supposed to be in file.");
}
Debug.Assert(result.LogRecord.RecordType == LogRecordType.Prepare, "Incorrect type of log record, expected Prepare record.");
return((PrepareLogRecord)result.LogRecord);
}
private static PrepareLogRecord ReadPrepareInternal(ITransactionFileReader reader, long pos)
{
var result = reader.TryReadAt(pos);
// TODO AN need to change this to account for possibly scavenged records, shouldn't throw exception,
// TODO AN rather return meaningful result
if (!result.Success)
{
throw new InvalidOperationException("Couldn't read record which is supposed to be in file.");
}
Debug.Assert(result.LogRecord.RecordType == LogRecordType.Prepare, "Incorrect type of log record, expected Prepare record.");
return((PrepareLogRecord)result.LogRecord);
}
private EpochRecord ReadEpochAt(ITransactionFileReader reader, long epochPos)
{
var result = reader.TryReadAt(epochPos);
if (!result.Success)
{
throw new Exception($"Could not find Epoch record at LogPosition {epochPos}.");
}
if (result.LogRecord.RecordType != LogRecordType.System)
{
throw new Exception($"LogRecord is not SystemLogRecord: {result.LogRecord}.");
}
var sysRec = (SystemLogRecord)result.LogRecord;
if (sysRec.SystemRecordType != SystemRecordType.Epoch)
{
throw new Exception($"SystemLogRecord is not of Epoch sub-type: {result.LogRecord}.");
}
return(sysRec.GetEpochRecord());
}
private static PrepareResult ReadPrepareInternal(ITransactionFileReader reader, long pos)
{
RecordReadResult result = reader.TryReadAt(pos);
if (!result.Success)
return new PrepareResult(false, null);
Debug.Assert(result.LogRecord.RecordType == LogRecordType.Prepare, "Incorrect type of log record, expected Prepare record.");
return new PrepareResult(true, (PrepareLogRecord)result.LogRecord);
}
public RecordReadResult TryReadAt(long position)
{
return(Reader.TryReadAt(position));
}
