Ensure that when an async read is performed on a response content the

errors are correctly dealt with.

Some network errors in iOS are exposed as Stream errors, specially those
related with the lost of the connection. This patch ensures that if such
an issue happens an exception is raised in the async read task.

Fixes bug https://bugzilla.xamarin.com/show_bug.cgi?id=53792

1 files changed, 20 insertions, 0 deletions

diff --git a/mcs/class/System.Net.Http/CFContentStream.cs b/mcs/class/System.Net.Http/CFContentStream.cs
index 270846cb6b7..d639ae2a29f 100644
--- a/mcs/class/System.Net.Http/CFContentStream.cs
+++ b/mcs/class/System.Net.Http/CFContentStream.cs
@@ -33,10 +33,13 @@ using System.Net;
 
 #if XAMCORE_4_0
 using CFNetwork;
+using CoreFoundation;
 #elif XAMCORE_2_0
 using CoreServices;
+using CoreFoundation;
 #else
 using MonoTouch.CoreServices;
+using MonoTouch.CoreFoundation;
 #endif
 
 namespace System.Net.Http
@@ -54,6 +57,7 @@ namespace System.Net.Http
 		Mutex data_mutex;
 		AutoResetEvent data_event;
 		AutoResetEvent data_read_event;
+		Exception http_exception = null;
 
 		// The requirements are:
 		// * We must read at least one byte from the stream every time
@@ -77,6 +81,7 @@ namespace System.Net.Http
 		public CFContentStream (CFHTTPStream stream)
 		{
 			this.http_stream = stream;
+			this.http_stream.ErrorEvent += HandleErrorEvent;
 			data = new BufferData () {
 				Buffer = new byte [4096],
 			};
@@ -85,6 +90,17 @@ namespace System.Net.Http
 			data_mutex = new Mutex ();
 		}
 
+		void HandleErrorEvent (object sender, CFStream.StreamEventArgs e)
+		{
+			var gotMutex = data_mutex.WaitOne ();
+			if (gotMutex) {
+				var stream = (CFHTTPStream)sender;
+				if (e.EventType == CFStreamEventType.ErrorOccurred)
+					http_exception = stream.GetError ();
+				data_mutex.ReleaseMutex ();
+			}
+		}
+
 		public void ReadStreamData ()
 		{
 			data_read_event.WaitOne (); // make sure there's no pending data.
@@ -111,6 +127,10 @@ namespace System.Net.Http
 		{
 			while (data_event.WaitOne ()) {
 				data_mutex.WaitOne ();
+				if (http_exception != null) {
+					data_mutex.ReleaseMutex ();
+					throw http_exception;
+				}
 				if (data == null || data.Length <= 0) {
 					data_mutex.ReleaseMutex ();
 					data_read_event.Set ();