route.h: introduce a macro, SA_SIZE(struct sockaddr *) which returns

the space occupied by a struct sockaddr when passed through a
routing socket.
Use it to replace the macro ROUNDUP(int), that does the same but
is redefined by every file which uses it, courtesy of
the School of Cut'n'Paste Programming(TM).

(partial) userland changes to follow.

1 files changed, 12 insertions, 0 deletions

diff --git a/sys/net/route.h b/sys/net/route.h
index 3f3b111..fb5d3ca 100644
--- a/sys/net/route.h
+++ b/sys/net/route.h
@@ -260,6 +260,18 @@ struct rt_addrinfo {
 	struct	ifnet *rti_ifp;
 };
 
+/*
+ * This macro returns the size of a struct sockaddr when passed
+ * through a routing socket. Basically we round up sa_len to
+ * a multiple of sizeof(long), with a minimum of sizeof(long).
+ * The check for a NULL pointer is just a convenience, probably never used.
+ * The case sa_len == 0 should only apply to empty structures.
+ */
+#define SA_SIZE(sa)						\
+    (  (!(sa) || ((struct sockaddr *)(sa))->sa_len == 0) ?	\
+	sizeof(long)		:				\
+	1 + ( (((struct sockaddr *)(sa))->sa_len - 1) | (sizeof(long) - 1) ) )
+
 #ifdef _KERNEL
 
 #define	RT_LOCK_INIT(_rt) \