Add pocketbus protocol.

[bertos.git] / cfg / macros.h

diff --git a/cfg/macros.h b/cfg/macros.h
index b3be457fb9b8c185aa0d1932678fdc39db1403cc..1006fc42e6ac9cfee30ce838aeb04a7953933b4f 100644 (file)
--- a/cfg/macros.h
+++ b/cfg/macros.h
@@ -60,13 +60,33 @@
                typeof(a) _a = (a); \
                typeof(b) _b = (b); \
                ASSERT_TYPE_EQUAL(_a, _b); \
-               (_a < _b) ? _a : _b; \
+               /** \
+                * The (typeof(_a)) cast in necessary: \
+                * result type of conditional expressions is \
+                * *NOT* the type of the value returned but \
+                * the type that would be produced if _a and _b \
+                * were mixed in an expression. \
+                * Even in _a and _b are of the same type, \
+                * if mixed in an expression the type will be \
+                * promoted to int! \
+               */ \
+               ((typeof(_a))((_a < _b) ? _a : _b)); \
        })
        #define MAX(a,b) ({ \
                typeof(a) _a = (a); \
                typeof(b) _b = (b); \
                ASSERT_TYPE_EQUAL(_a, _b); \
-               (_a > _b) ? _a : _b; \
+               /** \
+                * The (typeof(_a)) cast in necessary: \
+                * result type of conditional expressions is \
+                * *NOT* the type of the value returned but \
+                * the type that would be produced if _a and _b \
+                * were mixed in an expression. \
+                * Even in _a and _b are of the same type, \
+                * if mixed in an expression the type will be \
+                * promoted to int! \
+               */ \
+               ((typeof(_a))((_a > _b) ? _a : _b)); \
        })
 #else /* !(COMPILER_STATEMENT_EXPRESSIONS && COMPILER_TYPEOF) */
        /* Buggy macros for inferior compilers.  */
@@ -297,5 +317,20 @@
 #define ROTL(var, rot) (((var) << (rot)) | ((var) >> ((sizeof(var) * 8) - (rot))))
 /*\}*/
 
+/**
+ * Make an id from 4 letters, useful for
+ * file formats and kfile ids.
+ */
+#define MAKE_ID(a,b,c,d) \
+       ( ((uint32_t)(a) << 24) \
+       | ((uint32_t)(b) << 16) \
+       | ((uint32_t)(c) <<  8) \
+       | ((uint32_t)(d) <<  0) )
+
+/**
+ * Type for id generated by MAKE_ID().
+ */
+typedef uint32_t id_t;
+
 #endif /* MACROS_H */