1 /* LGPL (v2.1 or any later version) - see LICENSE file for details */
4 #include <ccan/time/time.h>
5 #include <ccan/list/list.h>
8 #ifndef TIMER_GRANULARITY
9 /* We divide all nsec values by 1000, reducing it to usec granularity. */
10 #define TIMER_GRANULARITY 1000
13 #ifndef TIMER_LEVEL_BITS
14 /* This gives 32 pointers per level, up to 13 levels deep. */
15 #define TIMER_LEVEL_BITS 5
22 * timers_init - initialize a timers struct.
23 * @timers: the struct timers
24 * @start: the minimum time which will ever be added.
26 * This sets up a timers struct: any timers added before @start will be
27 * set to expire immediately.
29 void timers_init(struct timers *timers, struct timespec start);
32 * timers_cleanup - free allocations within timers struct.
33 * @timers: the struct timers
35 * This frees any timer layers allocated during use.
37 void timers_cleanup(struct timers *timers);
40 * timer_add - insert a timer.
41 * @timers: the struct timers
42 * @timer: the (uninitialized) timer to add
43 * @when: when @timer expires.
45 * This efficiently adds @timer to @timers, to expire @when (rounded to
46 * TIMER_GRANULARITY nanoseconds).
48 void timer_add(struct timers *timers, struct timer *timer,
49 struct timespec when);
52 * timer_del - remove an unexpired timer.
53 * @timers: the struct timers
54 * @timer: the timer previously added with timer_add()
56 * This efficiently removes @timer from @timers.
58 void timer_del(struct timers *timers, struct timer *timer);
61 * timer_earliest - find out the first time when a timer will expire
62 * @timers: the struct timers
63 * @first: the time, only set if there is a timer.
65 * This returns false, and doesn't alter @first if there are no
66 * timers. Otherwise, it sets @first to the expiry time of the first
67 * timer (rounded to TIMER_GRANULARITY nanoseconds), and returns true.
69 bool timer_earliest(struct timers *timers, struct timespec *first);
72 * timer_expire - update timers structure and remove expired timers.
73 * @timers: the struct timers
74 * @expire: the current time
75 * @list: the list for expired timers.
77 * @list will be initialized to the empty list, then all timers added
78 * with a @when arg less than or equal to @expire will be added to it in
79 * expiry order (within TIMER_GRANULARITY nanosecond precision).
81 * After this, @expire is considered the current time, and adding any
82 * timers with @when before this value will be silently changed to
83 * adding them with immediate expiration.
85 * You should not move @expire backwards, though it need not move
88 void timers_expire(struct timers *timers,
89 struct timespec expire,
90 struct list_head *list);
93 * timers_check - check timer structure for consistency
94 * @t: the struct timers
95 * @abortstr: the location to print on aborting, or NULL.
97 * Because timers have redundant information, consistency checking can
98 * be done on the tree. This is useful as a debugging check. If
99 * @abortstr is non-NULL, that will be printed in a diagnostic if the
100 * timers structure is inconsistent, and the function will abort.
102 * Returns the timers struct if it is consistent, NULL if not (it can
103 * never return NULL if @abortstr is set).
105 struct timers *timers_check(const struct timers *t, const char *abortstr);
107 #ifdef CCAN_TIMER_DEBUG
111 * timers_dump - dump the timers datastructure (for debugging it)
112 * @t: the struct timers
113 * @fp: the FILE to dump to (stderr if @fp is NULL)
115 void timers_dump(const struct timers *timers, FILE *fp);
119 * struct timers - structure to hold a set of timers.
121 * Initialized using timers_init, the levels of the timer are
122 * allocated as necessary, using malloc.
125 * timers_init(), timers_cleanup()
128 /* Far in the future. */
129 struct list_head far;
133 struct timer_level *level[(64 + TIMER_LEVEL_BITS-1) / TIMER_LEVEL_BITS];
137 * struct timer - a single timer.
139 * Set up by timer_add(), this is usually contained within an
140 * application-specific structure.
143 * ccan/container_of, timer_add(), timer_del()
146 struct list_node list;
149 #endif /* CCAN_TIMER_H */