Rename C++ header files to .hpp

[lttng-tools.git] / src / common / optional.h

diff --git a/src/common/optional.h b/src/common/optional.h
deleted file mode 100644 (file)
index f34c599..0000000
--- a/src/common/optional.h
+++ /dev/null
@@ -1,106 +0,0 @@
-/*
- * Copyright (C) 2019 Jérémie Galarneau <jeremie.galarneau@efficios.com>
- *
- * SPDX-License-Identifier: GPL-2.0-only
- *
- */
-
-#ifndef LTTNG_OPTIONAL_H
-#define LTTNG_OPTIONAL_H
-
-#include <stdint.h>
-
-/*
- * Define wrapper structure representing an optional value.
- *
- * This macro defines an "is_set" boolean field that must be checked
- * when accessing the optional field. This "is_set" field provides
- * the semantics that would be expected of a typical "raw pointer" field
- * which would be checked for NULL.
- *
- * Prefer using this macro where "special" values would be used, e.g.
- * -1ULL for uint64_t types.
- *
- * Declaration example:
- * struct my_struct {
- *     int a;
- *     LTTNG_OPTIONAL(int) b;
- * };
- *
- * Usage example:
- * struct my_struct foo = LTTNG_OPTIONAL_INIT;
- *
- * LTTNG_OPTIONAL_SET(&foo.b, 42);
- * if (foo.b.is_set) {
- *     printf("%d", foo.b.value);
- * }
- *
- * LTTNG_OPTIONAL_UNSET(&foo.b);
- */
-#define LTTNG_OPTIONAL(type) \
-       struct {             \
-               uint8_t is_set; \
-               type value;  \
-       }
-
-/*
- * Alias used for communication structures. If the layout of an LTTNG_OPTIONAL
- * is changed, the original layout should still be used for communication
- * purposes.
- *
- * LTTNG_OPTIONAL_COMM should be combined with the LTTNG_PACKED macro when
- * used for IPC / network communication.
- */
-#define LTTNG_OPTIONAL_COMM LTTNG_OPTIONAL
-
-/*
- * This macro is available as a 'convenience' to allow sites that assume
- * an optional value is set to LTTNG_ASSERT() that it is set when accessing it.
- *
- * Since this returns the 'optional' by value, it is not suitable for all
- * wrapped optional types. It is meant to be used with PODs.
- */
-#define LTTNG_OPTIONAL_GET(optional)                   \
-       ({                                              \
-               LTTNG_ASSERT((optional).is_set);                \
-               (optional).value;                       \
-       })
-
-/*
- * This macro is available as a 'convenience' to allow sites that assume
- * an optional value is set to LTTNG_ASSERT() that it is set when fecthing the
- * underlying value's address.
- */
-#define LTTNG_OPTIONAL_GET_PTR(optional)                       \
-       ({                                              \
-               LTTNG_ASSERT((optional).is_set);                \
-               &(optional).value;                      \
-       })
-
-/*
- * 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_UNSET {}
-
-/*
- * Initialize an optional field as 'set' with a given value.
- */
-#define LTTNG_OPTIONAL_INIT_VALUE(val) { .is_set = 1, .value = val }
-
-/* Set the value of an optional field. */
-#define LTTNG_OPTIONAL_SET(field_ptr, val)     \
-       do {                                    \
-               (field_ptr)->is_set = 1;        \
-               (field_ptr)->value = (val);     \
-       } while (0)
-
-/* Put an optional field in the "unset" (NULL-ed) state. */
-#define LTTNG_OPTIONAL_UNSET(field_ptr)                \
-       do {                                    \
-               (field_ptr)->is_set = 0;        \
-       } while (0)
-
-#endif /* LTTNG_OPTIONAL_H */