X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;ds=sidebyside;f=src%2Fcommon%2Ftestpoint%2Ftestpoint.hpp;fp=src%2Fcommon%2Ftestpoint%2Ftestpoint.hpp;h=33cb9aa340cc71e64939be17844aaea3e42fa26c;hb=c9e313bc594f40a86eed237dce222c0fc99c957f;hp=0000000000000000000000000000000000000000;hpb=4878de5c7deb512bbdac4fdfc498907efa06fb7c;p=lttng-tools.git

diff --git a/src/common/testpoint/testpoint.hpp b/src/common/testpoint/testpoint.hpp
new file mode 100644
index 000000000..33cb9aa34
--- /dev/null
+++ b/src/common/testpoint/testpoint.hpp
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2012 Christian Babeux <christian.babeux@efficios.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ *
+ */
+
+#ifdef NTESTPOINT
+
+#define testpoint(name)
+#define TESTPOINT_DECL(name)
+
+#else /* NTESTPOINT */
+
+#include <urcu.h> /* for caa_likely/unlikely */
+
+extern int lttng_testpoint_activated;
+
+void *lttng_testpoint_lookup(const char *name);
+
+/*
+ * Testpoint is only active if the global lttng_testpoint_activated flag is
+ * set.
+ * Return a non-zero error code to indicate failure.
+ */
+#define testpoint(name)				\
+	((caa_unlikely(lttng_testpoint_activated))	\
+	? __testpoint_##name##_wrapper() : 0)
+
+/*
+ * One wrapper per testpoint is generated. This is to keep track of the symbol
+ * lookup status and the corresponding function pointer, if any.
+ */
+#define _TESTPOINT_DECL(_name)						\
+	static inline int __testpoint_##_name##_wrapper(void)		\
+	{								\
+		int ret = 0;						\
+		static int (*tp)(void);					\
+		static int found;					\
+		const char *tp_name = "__testpoint_" #_name;		\
+									\
+		if (tp) {						\
+			ret = tp();					\
+		} else {						\
+			if (!found) {					\
+				tp = (int (*)(void)) lttng_testpoint_lookup(tp_name);	\
+				if (tp) {				\
+					found = 1;			\
+					ret = tp();			\
+				} else {				\
+					found = -1;			\
+				}					\
+			}						\
+		}							\
+		return ret;						\
+	}
+
+/* Testpoint declaration */
+#define TESTPOINT_DECL(name)	\
+	_TESTPOINT_DECL(name)
+
+#endif /* NTESTPOINT */