/// <summary>
/// Not thread safe
/// </summary>
private DirectSingleFolderWriter GetExistingWriterByFolderKey(string folderKey)
{
DirectSingleFolderWriter retval = null;
_directWritersByFolderKey.TryGetValue(folderKey, out retval);
return(retval);
}
/// <summary>
/// Not thread safe
/// </summary>
private DirectSingleFolderWriter GetExistingWriterByRelativePath(string relativePath)
{
DirectSingleFolderWriter retval = null;
_directWritersByRelativePath.TryGetValue(relativePath, out retval);
return(retval);
}
/// <summary>
/// Check whether the writer is accessing data in the <paramref name="folder"/> or any of its descendants.
/// Descandants include <paramref name="folder" /> itself.
/// </summary>
/// <param name="folder">
/// <see cref="IRepositoryFolder"/> instance representing the subtree (the folder and all its descendants) root
/// </param>
/// <param name="subtree">
/// <code>bool</code> indicating whether to check access to any of the descendants of <paramref name="folder"/> (<see langword="true"/>)
/// or just <paramref name="folder"/> itself.
/// </param>
/// <returns>
/// <see langword="true"/> if the accessor is accessing data in the specified folder or folders
/// <see langword="false"/> otherwise
/// </returns>
/// <exception cref="ArgumentNullException">
/// <paramref name="folder"/> is <see langword="null"/>
/// </exception>
/// <exception cref="ArgumentException">
/// <paramref name="folder"/> is not attached to the same <see cref="IRepositoryManager"/> instance (<see cref="Repository"/>)
/// </exception>
/// <remarks>
/// If <paramref name="folder"/> is the same as <see cref="Folder"/> the method returns <see langword="true"/>, even before acceppting
/// any data.
/// </remarks>
public bool IsAccessing(IRepositoryFolder folder, bool subtree)
{
Check.DoRequireArgumentNotNull(folder, "folder");
if (!IsOpen)
{
return(false);
}
Exceptions.DifferentRepositoriesExceptionHelper.Check(folder.Repository, _repoFolder.Repository);
bool retval = object.ReferenceEquals(folder, this.Folder);
if (!retval)
{
lock (_directWritersByRelativePath)
{
if (subtree)
{
for (
var e = _directWritersByRelativePath.Values.GetEnumerator();
!retval && e.MoveNext();
retval = e.Current.Folder.IsDescendantOf(folder))
{
}
}
else
{
DirectSingleFolderWriter writer = GetExistingWriterByFolderKey(folder.FolderKey);
retval = writer != null && object.ReferenceEquals(folder, writer.Folder);
}
}
}
return(retval);
}
/// <summary>
/// Create single folder writer and add it to the collection of writers.
/// </summary>
/// <param name="targetFolder">
/// Target folder for writer
/// </param>
/// <returns>
/// New initialised instance. If the method succeeds (does not throw exception)
/// </returns>
/// <remarks>
/// Locking sequence: target folder lock start, then repo manager's registry lock/release, then direct writers collection lock/release,
/// then target folder released.
/// </remarks>
private DirectSingleFolderWriter CreateWriter(IRepositoryFolder targetFolder, string normalisedRelativePath)
{
Check.RequireArgumentNotNull(targetFolder, "targetFolder");
RepositoryFolder.CheckNotDetached(targetFolder);
IFolder folder = RepositoryFolder.CastFolder(targetFolder);
Exceptions.DifferentRepositoriesExceptionHelper.Check(Folder.Repository, targetFolder.Repository);
DirectSingleFolderWriter writer = null;
ICoder compressor = GetCompressor(targetFolder: targetFolder);
ICoder encryptor = GetEncryptor(targetFolder: targetFolder);
lock (targetFolder)
{
Check.DoAssertLambda(
object.ReferenceEquals(targetFolder, _repoFolder) || // this writer has already seized this folder as target
!Folder.Repository.IsDataBeingWrittenTo(targetFolder, false),
() => new InvalidOperationException(string.Format(StorageResources.WriterAlreadyExistsForFolder, targetFolder.LogicalPath)));
writer = new DirectSingleFolderWriter(folder, compressor, encryptor);
writer.EqualTimestampedItemsComparer = this.EqualTimestampedItemsComparer;
lock (_directWritersByRelativePath)
{
_directWritersByRelativePath.Add(normalisedRelativePath, writer);
_directWritersByFolderKey.Add(targetFolder.FolderKey, writer);
}
}
writer.TrackUnsavedItems = TrackUnsavedItems;
Check.Ensure(Repository.IsDataBeingWrittenTo(targetFolder, false));
return(writer);
}
