Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Configuration/System/Configuration/PropertySourceInfo.cs

@@ -0,0 +1,78 @@
+//------------------------------------------------------------------------------
+// <copyright file="PropertySourceInfo.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//------------------------------------------------------------------------------
+
+using System;
+using System.Configuration.Internal;
+using System.Collections;
+using System.Collections.Specialized;
+using System.Collections.Generic;
+using System.IO;
+using System.Reflection;
+using System.Security.Permissions;
+using System.Xml;
+using System.Globalization;
+using System.ComponentModel;
+using System.Security;
+using System.Text;
+
+namespace System.Configuration {
+
+    internal class PropertySourceInfo {
+        private string _fileName;
+        private int _lineNumber;
+
+        internal PropertySourceInfo(XmlReader reader) {
+            _fileName = GetFilename(reader);
+            _lineNumber = GetLineNumber(reader);
+        }
+
+        internal string FileName {
+            get {
+                //
+                // Ensure we return the same string to the caller as the one on which we issued the demand.
+                //
+                string filename = _fileName;
+                try {
+                    new FileIOPermission(FileIOPermissionAccess.PathDiscovery, filename).Demand();
+                }
+                catch (SecurityException) {
+                    // don't expose the path to this user but show the filename
+                    filename = Path.GetFileName(_fileName);
+                    if (filename == null) {
+                        filename = String.Empty;
+                    }
+                }
+
+                return filename;
+            }
+        }
+
+        internal int LineNumber {
+            get {
+                return _lineNumber;
+            }
+        }
+
+        private string GetFilename(XmlReader reader) {
+            IConfigErrorInfo err = reader as IConfigErrorInfo;
+
+            if (err != null) {
+                return (string)err.Filename;
+            }
+
+            return "";
+        }
+
+        private int GetLineNumber(XmlReader reader) {
+            IConfigErrorInfo err = reader as IConfigErrorInfo;
+
+            if (err != null) {
+                return (int)err.LineNumber;
+            }
+            return 0;
+        }
+    }
+}