macros.h: Implement side_enum_t

side_enum_t allows defining fixed-sized enumerations while preserving
typing information.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/include/side/macros.h b/include/side/macros.h
index 20fa97e804f07d76aae19d2afe1fe765620e6812..391537439e84741e0341f6b5d190f3c73a3ba641 100644 (file)
--- a/include/side/macros.h
+++ b/include/side/macros.h
@@ -123,4 +123,24 @@
 
 #define SIDE_PTR_INIT(...)     { .v = (uintptr_t) (__VA_ARGS__) }
 
+/*
+ * side_enum_t allows defining fixed-sized enumerations while preserving
+ * typing information.
+ */
+#define side_enum_t(_enum_type, _size_type)                    \
+       union {                                                 \
+               _size_type v;                                   \
+               _enum_type t[0];                                \
+       }
+
+#define side_enum_get(_field)                                  \
+       ((__typeof__((_field).t[0]))(_field).v)
+
+#define side_enum_set(_field, _v)                              \
+       do {                                                    \
+               (_field).v = (_v);                              \
+       } while (0)
+
+#define SIDE_ENUM_INIT(...)    { .v = (__VA_ARGS__) }
+
 #endif /* _SIDE_MACROS_H */