Prefix public header include guards with LTTNG_UST_

[lttng-ust.git] / include / lttng / tracepoint-types.h

diff --git a/include/lttng/tracepoint-types.h b/include/lttng/tracepoint-types.h
index 5f3870868d80e847d77b19c15661c9d3089c981a..42fe948657613d61c7df9db596abb023662287ad 100644 (file)
--- a/include/lttng/tracepoint-types.h
+++ b/include/lttng/tracepoint-types.h
@@ -1,45 +1,51 @@
-#ifndef _LTTNG_TRACEPOINT_TYPES_H
-#define _LTTNG_TRACEPOINT_TYPES_H
-
 /*
- * Copyright (C) 2008-2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- * Copyright (C) 2009 Pierre-Marc Fournier
- * Copyright (C) 2009 Steven Rostedt <rostedt@goodmis.org>
+ * SPDX-License-Identifier: MIT
  *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation;
- * version 2.1 of the License.
+ * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ */
+
+#ifndef _LTTNG_UST_TRACEPOINT_TYPES_H
+#define _LTTNG_UST_TRACEPOINT_TYPES_H
+
+#include <stdint.h>
+
+/*
+ * Tracepoint probe definition
  *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
+ * IMPORTANT: this structure is part of the ABI between instrumented
+ * applications and UST. This structure is fixed-size because it is part
+ * of a public array of structures. Rather than extending this
+ * structure, struct lttng_ust_tracepoint should be extended instead.
+ */
+
+struct lttng_ust_tracepoint_probe {
+       void (*func)(void);
+       void *data;
+};
+
+/*
+ * Tracepoint definition
  *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
+ * IMPORTANT: this structure is part of the ABI between instrumented
+ * applications and UST. Fields need to be only added at the end, never
+ * reordered, never removed.
  *
- * Heavily inspired from the Linux Kernel Markers.
+ * The field @struct_size should be used to determine the size of the
+ * structure. It should be queried before using additional fields added
+ * at the end of the structure.
  */
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+struct lttng_ust_tracepoint {
+       uint32_t struct_size;
 
-struct tracepoint_probe {
-       void *func;
-       void *data;
-};
+       const char *provider_name;
+       const char *event_name;
+       int state;
+       struct lttng_ust_tracepoint_probe *probes;
+       int *tracepoint_provider_ref;
+       const char *signature;
 
-struct tracepoint {
-       const char *name;               /* Tracepoint name */
-       char state;                     /* State. */
-       struct tracepoint_probe *probes;
+       /* End of base ABI. Fields below should be used after checking struct_size. */
 };
 
-#ifdef __cplusplus 
-}
-#endif
-
-#endif /* _LTTNG_TRACEPOINT_TYPES_H */
+#endif /* _LTTNG_UST_TRACEPOINT_TYPES_H */