[banshee] Fix handling of podcast feeds that don't specify their encoding

[Bertrand Lorentz <blorentz src gnome org>]

commit e3571217712db29a162abca76e5b674a2203384b
Author: Bertrand Lorentz <bertrand lorentz gmail com>
Date:   Wed Apr 29 22:25:35 2009 +0200

    Fix handling of podcast feeds that don't specify their encoding
    
    The feed was set as empty if it didn't contain an encoding attribute.
    This should at least fix part of BGO#574605.
---
 src/Libraries/Migo/Migo.Net/AsyncWebClient.cs |   18 ++++++++++--------
 1 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/src/Libraries/Migo/Migo.Net/AsyncWebClient.cs b/src/Libraries/Migo/Migo.Net/AsyncWebClient.cs
index 4d1871d..61c3dd9 100644
--- a/src/Libraries/Migo/Migo.Net/AsyncWebClient.cs
+++ b/src/Libraries/Migo/Migo.Net/AsyncWebClient.cs
@@ -726,14 +726,16 @@ namespace Migo.Net
                         if (s.StartsWith("<?xml")) {
                             string auxStr = "encoding=";
                             int startIndex = s.IndexOf (auxStr) + auxStr.Length + 1;
-                            int endIndex = s.IndexOf ('\"', startIndex);
-                            string encodingStr = s.Substring (startIndex, endIndex - startIndex);
-                            try {
-                                Encoding enc = Encoding.GetEncoding (encodingStr);
-                                if (!enc.Equals (Encoding)) {
-                                    s = enc.GetString (resultPtr);
-                                }
-                            } catch (ArgumentException) {}
+                            if (startIndex > auxStr.Length + 1) {
+                                int endIndex = s.IndexOf ('\"', startIndex);
+                                string encodingStr = s.Substring (startIndex, endIndex - startIndex);
+                                try {
+                                    Encoding enc = Encoding.GetEncoding (encodingStr);
+                                    if (!enc.Equals (Encoding)) {
+                                        s = enc.GetString (resultPtr);
+                                    }
+                                } catch (ArgumentException) {}
+                            }
                         }
                     } catch {
                         s = String.Empty;