--- /dev/null
+#ifndef BABELTRACE_GRAPH_MESSAGE_CONST_H
+#define BABELTRACE_GRAPH_MESSAGE_CONST_H
+
+/*
+ * Copyright 2017-2018 Philippe Proulx <pproulx@efficios.com>
+ * Copyright 2015 Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+/* For bt_message */
+#include <babeltrace2/types.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Message types. Unhandled message types should be ignored.
+ */
+typedef enum bt_message_type {
+ BT_MESSAGE_TYPE_EVENT = 0,
+ BT_MESSAGE_TYPE_MESSAGE_ITERATOR_INACTIVITY = 1,
+ BT_MESSAGE_TYPE_STREAM_BEGINNING = 2,
+ BT_MESSAGE_TYPE_STREAM_END = 3,
+ BT_MESSAGE_TYPE_PACKET_BEGINNING = 4,
+ BT_MESSAGE_TYPE_PACKET_END = 5,
+ BT_MESSAGE_TYPE_STREAM_ACTIVITY_BEGINNING = 6,
+ BT_MESSAGE_TYPE_STREAM_ACTIVITY_END = 7,
+ BT_MESSAGE_TYPE_DISCARDED_EVENTS = 8,
+ BT_MESSAGE_TYPE_DISCARDED_PACKETS = 9,
+} bt_message_type;
+
+/**
+ * Get a message's type.
+ *
+ * @param message Message instance
+ * @returns One of #bt_message_type
+ */
+extern bt_message_type bt_message_get_type(const bt_message *message);
+
+extern void bt_message_get_ref(const bt_message *message);
+
+extern void bt_message_put_ref(const bt_message *message);
+
+#define BT_MESSAGE_PUT_REF_AND_RESET(_var) \
+ do { \
+ bt_message_put_ref(_var); \
+ (_var) = NULL; \
+ } while (0)
+
+#define BT_MESSAGE_MOVE_REF(_var_dst, _var_src) \
+ do { \
+ bt_message_put_ref(_var_dst); \
+ (_var_dst) = (_var_src); \
+ (_var_src) = NULL; \
+ } while (0)
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* BABELTRACE_GRAPH_MESSAGE_CONST_H */