/* Function: PickDeletedFile
* Picks a deleted file to work on, if there are any. If not it will return null. Picked files will be added to <filesBeingProcessed>
* and must be released with <FinalizeDeletedFile()>.
*/
protected File PickDeletedFile()
{
lock (accessLock)
{
for (;;)
{
int fileID = Manager.UnprocessedChanges.PickDeletedFileID();
if (fileID == 0)
{
return(null);
}
// If it's not being processed by another thread, return it.
if (!filesBeingProcessed.Contains(fileID))
{
File file = Manager.FromID(fileID);
filesBeingProcessed.Add(file);
return(file);
}
// If it is being processed by another thread, discard it and pick again. It's okay to discard it from the list
// of changes because when processing ends FinalizeDeletedFile() will compare it to the snapshot in
// filesBeingProcessed and re-add it to the change list if it's different.
}
}
}
override protected void Dispose(bool strictRulesApply)
{
if (!strictRulesApply)
{
// Set the last modification time to zero for anything still being worked on
DateTime zero = new DateTime(0);
foreach (int id in unprocessedChangedFileIDs)
{
Manager.FromID(id).LastModified = zero;
}
foreach (int id in unprocessedDeletedFileIDs)
{
Manager.FromID(id).LastModified = zero;
}
foreach (int id in claimedFileIDs)
{
Manager.FromID(id).LastModified = zero;
}
}
}
/* Function: ClaimDeletedFile
* Claims a deleted file to work on, if there are any. Will return null if not. Claimed files must be released with
* <ReleaseClaimedFile()>.
*/
public File ClaimDeletedFile()
{
lock (accessLock)
{
if (unprocessedDeletedFileIDs.IsEmpty)
{
return(null);
}
int fileID = unprocessedDeletedFileIDs.Highest;
File file = Manager.FromID(fileID);
file.Claimed = true;
file.StatusSinceClaimed = FileFlags.UnchangedSinceClaimed;
unprocessedDeletedFileIDs.Remove(fileID);
claimedFileIDs.Add(fileID);
return(file);
}
}
