1 files changed, 69 insertions, 0 deletions
diff --git a/indra/llcommon/llstring.cpp b/indra/llcommon/llstring.cpp
index 514d73b24b..6f3d193d6b 100644
--- a/indra/llcommon/llstring.cpp
+++ b/indra/llcommon/llstring.cpp
@@ -1208,6 +1208,75 @@ namespace LLStringFn
         return output;
     }
 
+    using literals_t = std::map<char, std::string>;
+    static const literals_t xml_elem_literals =
+    {
+        { '<', "&lt;" },
+        { '>', "&gt;" },
+        { '&', "&amp;" }
+    };
+    static const literals_t xml_attr_literals =
+    {
+        { '"', "&quot;" },
+        { '\'', "&apos;" }
+    };
+
+    static void literals_encode(std::string& text, const literals_t& literals)
+    {
+        for (const std::pair<char, std::string> it : literals)
+        {
+            std::string::size_type pos = 0;
+            while ((pos = text.find(it.first, pos)) != std::string::npos)
+            {
+                text.replace(pos, 1, it.second);
+                pos += it.second.size();
+            }
+        }
+    }
+
+    static void literals_decode(std::string& text, const literals_t& literals)
+    {
+        for (const std::pair<char, std::string> it : literals)
+        {
+            std::string::size_type pos = 0;
+            while ((pos = text.find(it.second, pos)) != std::string::npos)
+            {
+                text[pos++] = it.first;
+                text.erase(pos, it.second.size() - 1);
+            }
+        }
+    }
+
+    /**
+     * @brief Replace all characters that are not allowed in XML 1.0
+     * with corresponding literals: [ < > & ] => [ &lt; &gt; &amp; ]
+     */
+    std::string xml_encode(const std::string& input, bool for_attribute)
+    {
+        std::string result(input);
+        literals_encode(result, xml_elem_literals);
+        if (for_attribute)
+        {
+            literals_encode(result, xml_attr_literals);
+        }
+        return result;
+    }
+
+    /**
+     * @brief Replace some of XML literals that are defined in XML 1.0
+     * with corresponding characters: [ &lt; &gt; &amp; ] => [ < > & ]
+     */
+    std::string xml_decode(const std::string& input, bool for_attribute)
+    {
+        std::string result(input);
+        literals_decode(result, xml_elem_literals);
+        if (for_attribute)
+        {
+            literals_decode(result, xml_attr_literals);
+        }
+        return result;
+    }
+
     /**
      * @brief Replace all control characters (c < 0x20) with replacement in
      * string.