chiark / gitweb /
sd-bus: remove unused call bus_kernel_create_monitor()
[elogind.git] / src / shared / macro.h
index 11bd8b3a93f097cfa822b74b3e72373f9c20403c..43fa3e556f33e2de9cd4b25dcede05152461763f 100644 (file)
@@ -140,6 +140,18 @@ static inline unsigned long ALIGN_POWER2(unsigned long u) {
                         _a > _b ? _a : _b;              \
                 })
 
+/* evaluates to (void) if _A or _B are not constant or of different types */
+#define CONST_MAX(_A, _B) \
+        __extension__ (__builtin_choose_expr(                           \
+                __builtin_constant_p(_A) &&                             \
+                __builtin_constant_p(_B) &&                             \
+                __builtin_types_compatible_p(typeof(_A), typeof(_B)),   \
+                ((_A) > (_B)) ? (_A) : (_B),                            \
+                (void)0))
+
+/* takes two types and returns the size of the larger one */
+#define MAXSIZE(A, B) (sizeof(union _packed_ { typeof(A) a; typeof(B) b; }))
+
 #define MAX3(x,y,z)                                     \
         __extension__ ({                                \
                         const typeof(x) _c = MAX(x,y);  \