diff options
author | Liping Zhang <zlpnobody@gmail.com> | 2017-02-05 21:57:34 +0800 |
---|---|---|
committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2017-02-28 12:10:09 +0100 |
commit | 24f8174646123c2833bc87967b366796231b04e0 (patch) | |
tree | b650166c7f6b47f95b3dad3401e0ad77ec9685a9 | |
parent | fc3c3b4ed38973bded55117ed27d928c1da09329 (diff) |
xshared: do not lock again and again if "-w" option is not specified
After running the following commands, some confusing messages was printed
out:
# while : ; do
iptables -A INPUT &
iptables -D INPUT &
done
[...]
Another app is currently holding the xtables lock; still -9s 0us time
ahead to have a chance to grab the lock...
Another app is currently holding the xtables lock; still -29s 0us time
ahead to have a chance to grab the lock...
If "-w" option is not specified, the "wait" will be zero, so we should
check whether the timer_left is less than wait_interval before we call
select to sleep.
Also remove unused "BASE_MICROSECONDS" and "struct timeval waited_time"
introduced by commit e8f857a5a151 ("xtables: Add an interval option for
xtables lock wait").
Fixes: e8f857a5a151 ("xtables: Add an interval option for xtables lock wait")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
-rw-r--r-- | iptables/xshared.c | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/iptables/xshared.c b/iptables/xshared.c index cccb8aec..055acf20 100644 --- a/iptables/xshared.c +++ b/iptables/xshared.c @@ -17,7 +17,6 @@ #include "xshared.h" #define XT_LOCK_NAME "/run/xtables.lock" -#define BASE_MICROSECONDS 100000 /* * Print out any special helps. A user might like to be able to add a --help @@ -249,13 +248,11 @@ void xs_init_match(struct xtables_match *match) bool xtables_lock(int wait, struct timeval *wait_interval) { - struct timeval time_left, wait_time, waited_time; + struct timeval time_left, wait_time; int fd, i = 0; time_left.tv_sec = wait; time_left.tv_usec = 0; - waited_time.tv_sec = 0; - waited_time.tv_usec = 0; fd = open(XT_LOCK_NAME, O_CREAT, 0600); if (fd < 0) @@ -264,6 +261,9 @@ bool xtables_lock(int wait, struct timeval *wait_interval) while (1) { if (flock(fd, LOCK_EX | LOCK_NB) == 0) return true; + else if (wait >= 0 && timercmp(&time_left, wait_interval, <)) + return false; + if (++i % 10 == 0) { if (wait != -1) fprintf(stderr, "Another app is currently holding the xtables lock; " @@ -279,10 +279,7 @@ bool xtables_lock(int wait, struct timeval *wait_interval) if (wait == -1) continue; - timeradd(&waited_time, wait_interval, &waited_time); timersub(&time_left, wait_interval, &time_left); - if (!timerisset(&time_left)) - return false; } } |