[B.A.T.M.A.N.] [PATCH 03/15] batman-adv: add biggest_unsigned_int(x) macro

Antonio Quartulli
2012-04-25T13:26:59Z

in case of dynamic type variable, it could be needed to compute at compile time
its maximal value. This macro helps in doing that for unsigned integer types

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
---
net/batman-adv/main.h | 3 +++
1 file changed, 3 insertions(+)

diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h
index a2b18d0..d9ef4ca 100644
--- a/net/batman-adv/main.h
+++ b/net/batman-adv/main.h
@@ -221,6 +221,9 @@ static inline bool has_timed_out(unsigned long timestamp, unsigned int timeout)
/* Returns the smallest signed integer in two's complement with the sizeof x */
#define smallest_signed_int(x) (1u << (7u + 8u * (sizeof(x) - 1u)))

+/* Returns the biggest unsigned integer with the sizeof x */
+#define biggest_unsigned_int(x) (~(x)0)
+
/* Checks if a sequence number x is a predecessor/successor of y.
* they handle overflows/underflows and can correctly check for a
* predecessor/successor unless the variable sequence number has grown by
--
1.7.9.4