private Stream OpenInputStream_NoLock()
{
string fp = DataFileFullPath;
if (mOpenOutputStream != null)
{
#if DEBUG
Debugger.Break();
#endif
throw new exception.OutputStreamOpenException(
"Cannot open an input Stream while an output Stream is open: " + fp);
}
FileStream inputFS;
CheckDataFile();
try
{
inputFS = new FileStream(fp, FileMode.Open, FileAccess.Read, FileShare.Read);
}
catch (Exception e)
{
#if DEBUG
Debugger.Break();
#endif
throw new exception.OperationNotValidException(
String.Format("Could not open file {0}", fp),
e);
}
CloseNotifyingStream res = new CloseNotifyingStream(inputFS);
res.StreamClosed += InputStreamClosed_StreamClosed;
mOpenInputStreams.Add(res);
return(res);
}
private void OutputStream_StreamClosed(object sender, EventArgs e)
{
if (ReferenceEquals(sender, mOpenOutputStream))
{
lock (m_lock)
{
mOpenOutputStream.StreamClosed -= new EventHandler(OutputStream_StreamClosed);
mOpenOutputStream = null;
}
}
}
private void InputStreamClosed_StreamClosed(object sender, EventArgs e)
{
CloseNotifyingStream cnStm = sender as CloseNotifyingStream;
if (cnStm != null)
{
lock (m_lock)
{
cnStm.StreamClosed -= InputStreamClosed_StreamClosed;
if (mOpenInputStreams.Contains(cnStm))
{
mOpenInputStreams.Remove(cnStm);
}
}
}
}
/// <summary>
/// Gets an output <see cref="Stream"/> providing write access to the <see cref="FileDataProvider"/>
/// </summary>
/// <returns>The ouput stream</returns>
/// <exception cref="exception.DataMissingException">
/// Thrown if the data stored in the <see cref="DataProvider"/> is missing from the underlying storage mechanism
/// </exception>
/// <exception cref="exception.InputStreamsOpenException">
/// Thrown if another output <see cref="Stream"/> from the data provider is already/still open
/// </exception>
/// <exception cref="exception.OutputStreamOpenException">
/// Thrown if another output <see cref="Stream"/> from the data provider is already/still open
/// </exception>
/// <exception cref="exception.OperationNotValidException">
/// Thrown if the underlying data file could not be opened in write-mode - see inner <see cref="Exception"/> for datails of cause
/// </exception>
public override Stream OpenOutputStream()
{
lock (m_lock)
{
string fp = DataFileFullPath;
if (mOpenOutputStream != null)
{
#if DEBUG
Debugger.Break();
#endif
throw new exception.OutputStreamOpenException(
"Cannot open an output Stream while another output Stream is already open: " + fp);
}
if (mOpenInputStreams.Count > 0)
{
#if DEBUG
Debugger.Break();
#endif
throw new exception.InputStreamsOpenException(
"Cannot open an output Stream while one or more input Streams are open: " + fp);
}
CheckDataFile();
FileStream outputFS;
try
{
outputFS = new FileStream(fp, FileMode.Open, FileAccess.Write, FileShare.None);
}
catch (Exception e)
{
throw new exception.OperationNotValidException(
String.Format("Could not open file {0}", fp),
e);
}
mOpenOutputStream = new CloseNotifyingStream(outputFS);
mOpenOutputStream.StreamClosed += OutputStream_StreamClosed;
return(mOpenOutputStream);
}
}
