/// <summary>
/// Cache version of GetResponseStream
/// </summary>
/// <returns></returns>
internal Stream GetResponseStream()
{
// prevent concurrent access to GetPart() which is not thread-safe
lock (_cacheEntry)
{
#if DEBUG
if (PackWebRequestFactory._traceSwitch.Enabled)
{
System.Diagnostics.Trace.TraceInformation(
DateTime.Now.ToLongTimeString() + " " + DateTime.Now.Millisecond + " " +
System.Threading.Thread.CurrentThread.ManagedThreadId + ": " +
"CachedResponse - Getting response stream");
}
#endif
// only one copy
if (_parent._responseStream == null)
{
// full container request?
if (_parent._partName == null)
{
Debug.Assert(false, "Cannot return full-container stream from cached container object");
}
else
{
#if DEBUG
if (PackWebRequestFactory._traceSwitch.Enabled)
{
System.Diagnostics.Trace.TraceInformation(
DateTime.Now.ToLongTimeString() + " " + DateTime.Now.Millisecond + " " +
System.Threading.Thread.CurrentThread.ManagedThreadId + ": " +
"CachedResponse - Getting part " + _parent._partName);
}
#endif
// open the requested stream
PackagePart p = _cacheEntry.GetPart(_parent._partName);
#if DEBUG
if (PackWebRequestFactory._traceSwitch.Enabled)
{
System.Diagnostics.Trace.TraceInformation(
DateTime.Now.ToLongTimeString() + " " + DateTime.Now.Millisecond + " " +
System.Threading.Thread.CurrentThread.ManagedThreadId + ": " +
"CachedResponse - Getting part stream ");
}
#endif
Stream s = p.GetSeekableStream(FileMode.Open, FileAccess.Read);
// Unless package is thread-safe, wrap the returned stream so that
// package access is serialized
if (!_cachedPackageIsThreadSafe)
{
// Return a stream that provides thread-safe access
// to the cached package by locking on the cached Package
s = new SynchronizingStream(s, _cacheEntry);
}
#if DEBUG
if (PackWebRequestFactory._traceSwitch.Enabled)
{
System.Diagnostics.Trace.TraceInformation(
DateTime.Now.ToLongTimeString() + " " + DateTime.Now.Millisecond + " " +
System.Threading.Thread.CurrentThread.ManagedThreadId + ": " +
"CachedResponse - Getting part contenttype");
}
#endif
_parent._mimeType = new MS.Internal.ContentType(p.ContentType);
// cache this in case they ask for it after the stream has been closed
_parent._lengthAvailable = s.CanSeek;
if (s.CanSeek)
{
#if DEBUG
if (PackWebRequestFactory._traceSwitch.Enabled)
{
System.Diagnostics.Trace.TraceInformation(
DateTime.Now.ToLongTimeString() + " " + DateTime.Now.Millisecond + " " +
System.Threading.Thread.CurrentThread.ManagedThreadId + ": " +
"CachedResponse - Length is available from stream");
}
#endif
_parent._fullStreamLength = s.Length;
}
#if DEBUG
else
{
if (PackWebRequestFactory._traceSwitch.Enabled)
{
System.Diagnostics.Trace.TraceInformation(
DateTime.Now.ToLongTimeString() + " " + DateTime.Now.Millisecond + " " +
System.Threading.Thread.CurrentThread.ManagedThreadId + ": " +
"CachedResponse - Length is not available from stream" + _parent._partName);
}
}
#endif
// re-use existing member variable
_parent._responseStream = s;
}
}
}
return(_parent._responseStream);
}
//------------------------------------------------------
//
// Public Methods
//
//------------------------------------------------------
#region WebResponse Overloads
/// <summary>
/// Retrieves a stream for reading bytes from the requested resource
/// </summary>
/// <returns>stream</returns>
public override Stream GetResponseStream()
{
CheckDisposed();
// redirect
if (FromPackageCache)
{
return(_cachedResponse.GetResponseStream());
}
EventTrace.EasyTraceEvent(EventTrace.Keyword.KeywordXPS, EventTrace.Event.WClientDRXGetStreamBegin);
#if DEBUG
if (PackWebRequestFactory._traceSwitch.Enabled)
{
System.Diagnostics.Trace.TraceInformation(
DateTime.Now.ToLongTimeString() + " " + DateTime.Now.Millisecond + " " +
System.Threading.Thread.CurrentThread.ManagedThreadId + ": " +
"PackWebResponse - GetResponseStream()");
}
#endif
// create and return only a single stream for multiple calls
if (_responseStream == null)
{
// can't do this until the response is available
WaitForResponse(); // after this call, we have a viable _fullResponse object because WaitForResponse would have thrown otherwise
// determine content length
long streamLength = _fullResponse.ContentLength;
#if DEBUG
if (_forceWebResponseLengthFailureSwitch.Enabled)
{
streamLength = -1;
}
// special handling for servers that won't or can't give us the length of the resource - byte-range downloading is impossible
if (streamLength <= 0)
{
if (PackWebRequestFactory._traceSwitch.Enabled)
{
System.Diagnostics.Trace.TraceInformation(
DateTime.Now.ToLongTimeString() + " " + DateTime.Now.Millisecond + " " +
System.Threading.Thread.CurrentThread.ManagedThreadId + ": " +
"PackWebResponse - GetResponseStream() - stream length not available - disabling progressive download");
}
}
#endif
// Start reading data from the response stream.
_responseStream = _fullResponse.GetResponseStream();
// require NetStream for progressivity and for network streams that don't
// directly support seeking.
if (!_responseStream.CanSeek || !_innerUri.IsFile)
{
// Create a smart stream that will spawn byte-range requests as needed
// and support seeking. Each read has overhead of Mutex and many of the
// reads come through asking for 4 bytes at a time
_responseStream = new NetStream(
_responseStream, streamLength,
_innerUri, _webRequest, _fullResponse);
// wrap our stream for efficiency (short reads are expanded)
_responseStream = new BufferedStream(_responseStream);
}
// handle degenerate case where there is no part name
if (_partName == null)
{
_fullStreamLength = streamLength; // entire container
_mimeType = WpfWebRequestHelper.GetContentType(_fullResponse);
// pass this so that ResponseStream holds a reference to us until the stream is closed
_responseStream = new ResponseStream(_responseStream, this);
}
else
{
// open container on netStream
Package c = Package.Open(_responseStream);
if (!c.PartExists(_partName))
{
throw new WebException(SR.Get(SRID.WebResponsePartNotFound));
}
PackagePart p = c.GetPart(_partName);
Stream s = p.GetSeekableStream(FileMode.Open, FileAccess.Read);
_mimeType = new MS.Internal.ContentType(p.ContentType); // save this for use in ContentType property - may still be null
_fullStreamLength = s.Length; // just this stream
// Wrap in a ResponseStream so that this container will be released
// when the stream is closed
_responseStream = new ResponseStream(s, this, _responseStream, c);
}
// length available? (-1 means the server chose not to report it)
if (_fullStreamLength >= 0)
{
_lengthAvailable = true;
}
}
EventTrace.EasyTraceEvent(EventTrace.Keyword.KeywordXPS, EventTrace.Event.WClientDRXGetStreamEnd);
return(_responseStream);
}