X-Git-Url: https://git.ozlabs.org/?a=blobdiff_plain;f=ccan%2Ftimer%2Ftimer.h;h=e678f7f7dfcbf78274e89ecbefcdc8e320992f0b;hb=61c38f61b8a40dbd8fe48b7510e00cfcc5379378;hp=d6e81e8cacbf2dfe94f3d73468e8a70aa12caa7c;hpb=d69e61ce142e6dbca6e888cfd0f7b4f977cc872d;p=ccan diff --git a/ccan/timer/timer.h b/ccan/timer/timer.h index d6e81e8c..e678f7f7 100644 --- a/ccan/timer/timer.h +++ b/ccan/timer/timer.h @@ -31,7 +31,7 @@ struct timer; * * timers_init(&timeouts, time_now()); */ -void timers_init(struct timers *timers, struct timespec start); +void timers_init(struct timers *timers, struct timeabs start); /** * timers_cleanup - free allocations within timers struct. @@ -44,30 +44,40 @@ void timers_init(struct timers *timers, struct timespec start); */ void timers_cleanup(struct timers *timers); +/** + * timer_init - initialize a timer. + * @timer: the timer to initialize + * + * Example: + * struct timer t; + * + * timer_init(&t); + */ +void timer_init(struct timer *t); + /** * timer_add - insert a timer. * @timers: the struct timers - * @timer: the (uninitialized) timer to add + * @timer: the (initialized or timer_del'd) timer to add * @when: when @timer expires. * * This efficiently adds @timer to @timers, to expire @when (rounded to * TIMER_GRANULARITY nanoseconds). * * Example: - * struct timer t; - * * // Timeout in 100ms. - * timer_add(&timeouts, &t, time_add(time_now(), time_from_msec(100))); + * timer_add(&timeouts, &t, timeabs_add(time_now(), time_from_msec(100))); */ -void timer_add(struct timers *timers, struct timer *timer, - struct timespec when); +void timer_add(struct timers *timers, struct timer *timer, struct timeabs when); /** - * timer_del - remove an unexpired timer. + * timer_del - remove a timer. * @timers: the struct timers - * @timer: the timer previously added with timer_add() + * @timer: the timer * - * This efficiently removes @timer from @timers. + * This efficiently removes @timer from @timers, if timer_add() was + * called. It can be called multiple times without bad effect, and + * can be called any time after timer_init(). * * Example: * timer_del(&timeouts, &t); @@ -77,45 +87,42 @@ void timer_del(struct timers *timers, struct timer *timer); /** * timer_earliest - find out the first time when a timer will expire * @timers: the struct timers - * @first: the time, only set if there is a timer. + * @first: the expiry time, only set if there is a timer. * * This returns false, and doesn't alter @first if there are no * timers. Otherwise, it sets @first to the expiry time of the first * timer (rounded to TIMER_GRANULARITY nanoseconds), and returns true. * * Example: - * struct timespec next = { (time_t)-1ULL, -1UL }; + * struct timeabs next = { { (time_t)-1ULL, -1UL } }; * timer_earliest(&timeouts, &next); */ -bool timer_earliest(struct timers *timers, struct timespec *first); +bool timer_earliest(struct timers *timers, struct timeabs *first); /** - * timers_expire - update timers structure and remove expired timers. + * timers_expire - update timers structure and remove one expire timer. * @timers: the struct timers * @expire: the current time - * @list: the list for expired timers. * - * @list will be initialized to the empty list, then all timers added - * with a @when arg less than or equal to @expire will be added to it in - * expiry order (within TIMER_GRANULARITY nanosecond precision). + * A timers added with a @when arg less than or equal to @expire will be + * returned (within TIMER_GRANULARITY nanosecond precision). If + * there are no timers due to expire, NULL is returned. * - * After this, @expire is considered the current time, and adding any - * timers with @when before this value will be silently changed to - * adding them with immediate expiration. + * After this returns NULL, @expire is considered the current time, + * and adding any timers with @when before this value will be silently + * changed to adding them with immediate expiration. * * You should not move @expire backwards, though it need not move * forwards. * * Example: - * struct list_head expired; + * struct timer *expired; * - * timers_expire(&timeouts, time_now(), &expired); - * if (!list_empty(&expired)) + * while ((expired = timers_expire(&timeouts, time_now())) != NULL) * printf("Timer expired!\n"); + * */ -void timers_expire(struct timers *timers, - struct timespec expire, - struct list_head *list); +struct timer *timers_expire(struct timers *timers, struct timeabs expire); /** * timers_check - check timer structure for consistency @@ -158,8 +165,12 @@ void timers_dump(const struct timers *timers, FILE *fp); struct timers { /* Far in the future. */ struct list_head far; + /* Current time. */ uint64_t base; + /* Overall first value. */ uint64_t first; + /* First value in each level (plus 1 for far list) */ + uint64_t firsts[(64 + TIMER_LEVEL_BITS-1) / TIMER_LEVEL_BITS + 1]; struct timer_level *level[(64 + TIMER_LEVEL_BITS-1) / TIMER_LEVEL_BITS]; };