diff options
author | Antonio Quartulli <ordex@autistici.org> | 2011-05-18 07:20:50 (GMT) |
---|---|---|
committer | Sven Eckelmann <sven@narfation.org> | 2011-05-30 05:39:35 (GMT) |
commit | f5d33d37786af139cecde5af831d64a671bb756b (patch) | |
tree | 6978df634a520e574fbd10ec62c980d3079fdcd3 /net/batman-adv | |
parent | 728cbc6ac1eef89660875c70a602c1a0ba8df4ff (diff) | |
download | linux-f5d33d37786af139cecde5af831d64a671bb756b.tar.xz |
batman-adv: move smallest_signed_int(), seq_before() and seq_after() into main.h
smallest_signed_int(), seq_before() and seq_after() are very useful
functions that help to handle comparisons between sequence numbers.
However they were only defined in vis.c. With this patch every
batman-adv function will be able to use them.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Diffstat (limited to 'net/batman-adv')
-rw-r--r-- | net/batman-adv/main.h | 16 | ||||
-rw-r--r-- | net/batman-adv/vis.c | 16 |
2 files changed, 16 insertions, 16 deletions
diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h index 0150897a..80be5ad 100644 --- a/net/batman-adv/main.h +++ b/net/batman-adv/main.h @@ -182,4 +182,20 @@ static inline int compare_eth(const void *data1, const void *data2) #define atomic_dec_not_zero(v) atomic_add_unless((v), -1, 0) +/* Returns the smallest signed integer in two's complement with the sizeof x */ +#define smallest_signed_int(x) (1u << (7u + 8u * (sizeof(x) - 1u))) + +/* 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 + * more then 2**(bitwidth(x)-1)-1. + * This means that for a uint8_t with the maximum value 255, it would think: + * - when adding nothing - it is neither a predecessor nor a successor + * - before adding more than 127 to the starting value - it is a predecessor, + * - when adding 128 - it is neither a predecessor nor a successor, + * - after adding more than 127 to the starting value - it is a successor */ +#define seq_before(x, y) ({typeof(x) _dummy = (x - y); \ + _dummy > smallest_signed_int(_dummy); }) +#define seq_after(x, y) seq_before(y, x) + #endif /* _NET_BATMAN_ADV_MAIN_H_ */ diff --git a/net/batman-adv/vis.c b/net/batman-adv/vis.c index ea8d7e9..355c6e5 100644 --- a/net/batman-adv/vis.c +++ b/net/batman-adv/vis.c @@ -30,22 +30,6 @@ #define MAX_VIS_PACKET_SIZE 1000 -/* Returns the smallest signed integer in two's complement with the sizeof x */ -#define smallest_signed_int(x) (1u << (7u + 8u * (sizeof(x) - 1u))) - -/* 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 - * more then 2**(bitwidth(x)-1)-1. - * This means that for a uint8_t with the maximum value 255, it would think: - * - when adding nothing - it is neither a predecessor nor a successor - * - before adding more than 127 to the starting value - it is a predecessor, - * - when adding 128 - it is neither a predecessor nor a successor, - * - after adding more than 127 to the starting value - it is a successor */ -#define seq_before(x, y) ({typeof(x) _dummy = (x - y); \ - _dummy > smallest_signed_int(_dummy); }) -#define seq_after(x, y) seq_before(y, x) - static void start_vis_timer(struct bat_priv *bat_priv); /* free the info */ |