1 files changed, 74 insertions, 0 deletions
diff --git a/indra/newview/llviewerhelputil.cpp b/indra/newview/llviewerhelputil.cpp
index ef4b955a5e..4d18a791fc 100644
--- a/indra/newview/llviewerhelputil.cpp
+++ b/indra/newview/llviewerhelputil.cpp
@@ -39,6 +39,80 @@
 // Build a help URL from a topic and formatter
 
 //static
+std::string LLViewerHelpUtil::helpDataEncode(const std::string &component)
+{
+    const std::string data_marker = "data:";
+    if (component.compare(0, data_marker.length(), data_marker) == 0)
+    {
+        // This is not url, but data, data part needs to be properly escaped
+        // data part is separated by ',' from header. Minimal data uri is "data:,"
+        // See "data URI scheme"
+        size_t separator = component.find(",");
+        if (separator != std::string::npos)
+        {
+            size_t header_size = separator + 1;
+            std::string header = component.substr(0, header_size);
+            if (header.find("base64") != std::string::npos)
+            {
+                // assume url-safe data
+                return component;
+            }
+
+            std::string data = component.substr(header_size, component.length() - header_size);
+            
+            const std::string allowed_sorted =
+                "%-." //include % since it can be a sign of being pre-escaped and is an allowed symbol
+                "0123456789"
+                "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+                "_"
+                "abcdefghijklmnopqrstuvwxyz";
+
+            bool needs_escaping = false;
+
+            std::string::const_iterator it = data.begin();
+            std::string::const_iterator end = data.end();
+            std::string::const_iterator allowed_begin(allowed_sorted.begin());
+            std::string::const_iterator allowed_end(allowed_sorted.end());
+            std::string::value_type c;
+            for (; it != end; ++it)
+            {
+                c = *it;
+                if (!std::binary_search(allowed_begin, allowed_end, c))
+                {
+                    // found unescaped symbol
+                    needs_escaping = true;
+                    break;
+                }
+            }
+
+            if (!needs_escaping)
+            {
+                // pre-escaped
+                return component;
+            }
+
+            // Notes: Teoretically file can be partially pre-escaped,
+            // but we can't reliably distinguish what user intended to do,
+            // so escape everything and let user control the rest.
+            // Escapes % as well
+            std::string url = header + helpURLEncode(data);
+
+            return url;
+        }
+        else
+        {
+            // corrupted or not a data scheme? Nothing we can do.
+            return component;
+        }
+    }
+    else
+    {
+        // Not a data scheme
+        return component;
+    }
+}
+
+//static
 std::string LLViewerHelpUtil::helpURLEncode( const std::string &component )
 {
 	// Every character rfc3986 allows as unreserved in 2.3, minus the tilde