optional: Add LTTNG_OPTIONAL_INIT_VALUE

Add helper to initialize an optional field to a 'set' value.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: I439302ebec2433abcf7edb6167bf5b02db5a9a55

diff --git a/src/common/optional.h b/src/common/optional.h
index faa64bf604e424adc2aefcda50b044c028c0a507..ca7d1f043d21bdef1b9ad8dc716452ee49fe7858 100644 (file)
--- a/src/common/optional.h
+++ b/src/common/optional.h
@@ -79,12 +79,17 @@
        })
 
 /*
- * Initialize an optional field.
+ * Initialize an optional field as unset.
  *
  * The wrapped field is set to the value it would gave if it had static storage
  * duration.
  */
-#define LTTNG_OPTIONAL_INIT { .is_set = 0 }
+#define LTTNG_OPTIONAL_INIT_UNSET { .is_set = 0 }
+
+/*
+ * Initialize an optional field as 'set' with a given value.
+ */
+#define LTTNG_OPTIONAL_INIT_VALUE(val) { .value = val, .is_set = 1 }
 
 /* Set the value of an optional field. */
 #define LTTNG_OPTIONAL_SET(field_ptr, val)     \