* mu-msg, mu-msg-file: fix up mu_msg_get_header

src/mu-msg.c

@@ -249,6 +249,23 @@ get_num_field (MuMsg *self, MuMsgFieldId mfid)
 }
 
 
+const char*
+mu_msg_get_header (MuMsg *self, const char *header)
+{
+	g_return_val_if_fail (self, NULL);
+	g_return_val_if_fail (header, NULL);
+
+	/* if we don't have a file object yet, we need to
+	 * create it from the file on disk */
+	if (!self->_file)
+		self->_file = get_msg_file (self);
+	if (!self->_file && !(self->_file = get_msg_file (self)))
+		return NULL;
+
+	return mu_msg_file_get_header (self->_file, header);
+}
+
+
 const char*    
 mu_msg_get_path (MuMsg *self)
 {