Escapes special characters in originate variables

NEventSocket.Tests/Applications/OriginateTests.cs

@@ -55,6 +55,17 @@ public void can_set_enterprise_channel_variables_and_channel_variables()
             Assert.That(options, Does.Contain("<e1='ev1',e2='ev2'>{c1='cv1',c2='cv2'}"));
         }
 
+        [Test]
+        public void must_escape_enterprise_channel_variables()
+        {
+            var options = new OriginateOptions
+                          {
+                              EnterpriseChannelVariables = new Dictionary<string, string> { { "e1", "<incident1>ev1</incident1>" }, { "e2", "<incident2>ev2</incident2>" } },
+                              ChannelVariables = new Dictionary<string, string> { { "c1", "cv1" }, { "c2", "cv2" } }
+                          }.ToString();
+            Assert.That(options, Does.Contain("<e1='\\<incident1\\>ev1\\</incident1\\>',e2='\\<incident2\\>ev2\\</incident2\\>'>{c1='cv1',c2='cv2'}"));
+        }
+
         [Test]
         public void can_set_caller_id_type()
         {

NEventSocket/FreeSwitch/OriginateOptions.cs

@@ -289,7 +289,7 @@ private void AppendOriginateEnterpriseChannelVariablesString(StringBuilder sb)
 
             sb.Append("<");
 
-            sb.Append(EnterpriseChannelVariables.ToOriginateString());
+            sb.Append(EnterpriseChannelVariables.EscapeValues(new[] { '<', '>' }).ToOriginateString());
 
             if (sb.Length > 1)
             {

NEventSocket/Util/StringExtensions.cs

@@ -226,5 +226,41 @@ public static string ToOriginateString(this IDictionary<string, string> dictiona
 
             return StringBuilderPool.ReturnAndFree(sb);
         }
+
+        public static IDictionary<string, string> EscapeValues(this IDictionary<string, string> dictionary, IEnumerable<char> charactersToEscape)
+        {
+            if (dictionary == null)
+                throw new ArgumentNullException(nameof(dictionary));
+
+            if (charactersToEscape == null)
+                throw new ArgumentNullException(nameof(charactersToEscape));
+
+            var escapeSet = charactersToEscape as HashSet<char> ?? [.. charactersToEscape];
+            var result = new Dictionary<string, string>();
+
+            foreach (var kvp in dictionary)
+            {
+                var escapedValue = kvp.Value != null ? EscapeString(kvp.Value, escapeSet) : kvp.Value;
+                result[kvp.Key] = escapedValue;
+            }
+
+            return result;
+        }
+
+        private static string EscapeString(string input, HashSet<char> charactersToEscape)
+        {
+            var sb = StringBuilderPool.Allocate();
+
+            foreach (char c in input)
+            {
+                if (charactersToEscape.Contains(c))
+                {
+                    sb.Append('\\');
+                }
+                sb.Append(c);
+            }
+
+            return StringBuilderPool.ReturnAndFree(sb);
+        }
     }
 }