- try {
- 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())
+ Xapian::valueno slot = Xapian::BAD_VALUENO;
+
+ /* Fetch header from the appropriate xapian value field if
+ * available */
+ if (strcasecmp (header, "from") == 0)
+ slot = NOTMUCH_VALUE_FROM;
+ else if (strcasecmp (header, "subject") == 0)
+ slot = NOTMUCH_VALUE_SUBJECT;
+ else if (strcasecmp (header, "message-id") == 0)
+ slot = NOTMUCH_VALUE_MESSAGE_ID;
+
+ if (slot != Xapian::BAD_VALUENO) {
+ try {
+ std::string value = message->doc.get_value (slot);
+
+ /* If we have NOTMUCH_FEATURE_FROM_SUBJECT_ID_VALUES, then
+ * empty values indicate empty headers. If we don't, then
+ * it could just mean we didn't record the header. */
+ if ((message->notmuch->features &
+ NOTMUCH_FEATURE_FROM_SUBJECT_ID_VALUES) ||
+ ! value.empty())