Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Data.SqlXml/System/Xml/Xsl/XsltOld/DocumentScope.cs

@@ -0,0 +1,52 @@
+//------------------------------------------------------------------------------
+// <copyright file="DocumentScope.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>                                                                
+// <owner current="true" primary="true">[....]</owner>
+//------------------------------------------------------------------------------
+
+namespace System.Xml.Xsl.XsltOld {
+    using Res = System.Xml.Utils.Res;
+    using System;
+    using System.Diagnostics;
+    using System.Xml;
+    using System.Xml.XPath;
+
+    internal class DocumentScope {
+        protected NamespaceDecl scopes;
+
+        internal NamespaceDecl Scopes {
+            get { return this.scopes; }
+        }
+
+        internal NamespaceDecl AddNamespace(string prefix, string uri, string prevDefaultNsUri) {
+            this.scopes = new NamespaceDecl(prefix, uri, prevDefaultNsUri, this.scopes);
+            return this.scopes;
+        }
+
+        internal string ResolveAtom(string prefix) {
+            Debug.Assert(prefix != null && prefix.Length > 0);
+
+            for (NamespaceDecl scope = this.scopes; scope != null; scope = scope.Next) {
+                if (Ref.Equal(scope.Prefix, prefix)) {
+                    Debug.Assert(scope.Uri != null);
+                    return scope.Uri;
+                }
+            }
+
+            return null;
+        }
+
+        internal string ResolveNonAtom(string prefix) {
+            Debug.Assert(prefix != null && prefix.Length > 0);
+
+            for (NamespaceDecl scope = this.scopes; scope != null; scope = scope.Next) {
+                if (scope.Prefix == prefix) {
+                    Debug.Assert(scope.Uri != null);
+                    return scope.Uri;
+                }
+            }
+            return null;
+        }
+    }
+}