+ std::string value;
+
+ /* Fetch header from the appropriate xapian value field if
+ * available */
+ if (strcasecmp (header, "from") == 0)
+ value = message->doc.get_value (NOTMUCH_VALUE_FROM);
+ else if (strcasecmp (header, "subject") == 0)
+ value = message->doc.get_value (NOTMUCH_VALUE_SUBJECT);
+ else if (strcasecmp (header, "message-id") == 0)
+ value = message->doc.get_value (NOTMUCH_VALUE_MESSAGE_ID);
+
+ if (!value.empty())
+ return talloc_strdup (message, value.c_str ());
+
+ /* Otherwise fall back to parsing the file */