public IEnumerable <JournalEntry> GetEntries(Usn currentUSN, ChangeReason reasonFilter, bool returnOnlyOnClose, TimeSpan timeout)
{
if (currentUSN < Data.FirstUSN || currentUSN > Data.MaximumUSN)
{
throw new ArgumentOutOfRangeException(nameof(currentUSN));
}
return(new ChangeJournalEntries(this, new ReadChangeJournalOptions(currentUSN, reasonFilter, returnOnlyOnClose, timeout)));
}
private bool Read()
{
const int CurrentUSNLength = sizeof(long);
var readData = new READ_USN_JOURNAL_DATA_V0
{
StartUsn = _currentUSN,
ReasonMask = Options.ReasonFilter,
UsnJournalID = ChangeJournal.Data.ID,
ReturnOnlyOnClose = Options.ReturnOnlyOnClose ? (uint)1 : 0,
Timeout = (ulong)Options.Timeout.TotalSeconds,
};
var handle = ChangeJournal.ChangeJournalHandle;
var entryData = Win32DeviceControl.ControlWithInput(handle, Win32ControlCode.ReadUsnJournal, ref readData, BufferSize);
if (entryData.Length > CurrentUSNLength) // There are more data than just data currentUSN.
{
var bufferHandle = GCHandle.Alloc(entryData, GCHandleType.Pinned);
var bufferPointer = bufferHandle.AddrOfPinnedObject();
_currentUSN = Marshal.ReadInt64(entryData, 0);
// Enumerate entries
_entries.Clear();
var offset = CurrentUSNLength; // Skip currentUSN field
while (offset < entryData.Length)
{
var entry = GetBufferedEntry(bufferPointer, offset);
offset += entry.Length;
_entries.Add(entry);
}
bufferHandle.Free();
_currentIndex = 0;
return(true);
}
else
{
_eof = true;
return(false);
}
}
public void Reset()
{
_currentUSN = Options.InitialUSN ?? ChangeJournal.Data.FirstUSN;
_currentIndex = -1;
}