zebra: kernel_socket: fix 64bit MacOS X alignment
In OS X 10.7 zebra crashed on invalid execution address.
sockaddr padding in *_msghdr is observed to be 4 bytes in 64bit OS X.
The ROUNDUP macro assumed alignment on sizeof(long) which
allocates 8 bytes on 64bit systems, 4 bytes on 32bit systems
which is true for BSD generally.
Test for Apple and use sizeof(int) which allocates 4 bytes on 32 & 64bit
systems.
Tested on 64bit OS X 10.7, FreeBSD 9.0 amd64 & i386 (32bit)
using gcc & clang
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/zebra/kernel_socket.c b/zebra/kernel_socket.c
index b7061e7..ecc6e79 100644
--- a/zebra/kernel_socket.c
+++ b/zebra/kernel_socket.c
@@ -48,9 +48,15 @@
* XXX: why is ROUNDUP(0) sizeof(long)? 0 is an illegal sockaddr
* length anyway (< sizeof (struct sockaddr)), so this shouldn't
* matter.
+ * On OS X, both 32, 64bit syatems align on 4 byte boundary
*/
+#ifdef __APPLE__
+#define ROUNDUP(a) \
+ ((a) > 0 ? (1 + (((a) - 1) | (sizeof(int) - 1))) : sizeof(int))
+#else
#define ROUNDUP(a) \
((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
+#endif
/*
* Given a pointer (sockaddr or void *), return the number of bytes