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 /* We divide all nsec values by 1000, reducing it to usec granularity. */
9 #define TIMER_GRANULARITY 1000
10 /* This gives 16 pointers per level, up to 13 levels deep. */
11 #define TIMER_LEVEL_BITS 4
17 * timers_init - initialize a timers struct.
18 * @timers: the struct timers
19 * @start: the minimum time which will ever be added.
21 * This sets up a timers struct: any timers added before @start will be
22 * set to expire immediately.
24 void timers_init(struct timers *timers, struct timespec start);
27 * timers_cleanup - free allocations within timers struct.
28 * @timers: the struct timers
30 * This frees any timer layers allocated during use.
32 void timers_cleanup(struct timers *timers);
35 * timer_add - insert a timer.
36 * @timers: the struct timers
37 * @timer: the (uninitialized) timer to add
38 * @when: when @timer expires.
40 * This efficiently adds @timer to @timers, to expire @when (rounded to
41 * TIMER_GRANULARITY nanoseconds).
43 void timer_add(struct timers *timers, struct timer *timer,
44 struct timespec when);
47 * timer_del - remove an unexpired timer.
48 * @timers: the struct timers
49 * @timer: the timer previously added with timer_add()
51 * This efficiently removes @timer from @timers.
53 void timer_del(struct timers *timers, struct timer *timer);
56 * timer_earliest - find out the first time when a timer will expire
57 * @timers: the struct timers
58 * @first: the time, only set if there is a timer.
60 * This returns false, and doesn't alter @first if there are no
61 * timers. Otherwise, it sets @first to the expiry time of the first
62 * timer (rounded to TIMER_GRANULARITY nanoseconds), and returns true.
64 bool timer_earliest(struct timers *timers, struct timespec *first);
67 * timer_expire - update timers structure and remove expired timers.
68 * @timers: the struct timers
69 * @expire: the current time
70 * @list: the list for expired timers.
72 * @list will be initialized to the empty list, then all timers added
73 * with a @when arg less than or equal to @expire will be added to it in
74 * expiry order (within TIMER_GRANULARITY nanosecond precision).
76 * After this, @expire is considered the current time, and adding any
77 * timers with @when before this value will be silently changed to
78 * adding them with immediate expiration.
80 * You should not move @expire backwards, though it need not move
83 void timers_expire(struct timers *timers,
84 struct timespec expire,
85 struct list_head *list);
88 * timers_check - check timer structure for consistency
89 * @t: the struct timers
90 * @abortstr: the location to print on aborting, or NULL.
92 * Because timers have redundant information, consistency checking can
93 * be done on the tree. This is useful as a debugging check. If
94 * @abortstr is non-NULL, that will be printed in a diagnostic if the
95 * timers structure is inconsistent, and the function will abort.
97 * Returns the timers struct if it is consistent, NULL if not (it can
98 * never return NULL if @abortstr is set).
100 struct timers *timers_check(const struct timers *t, const char *abortstr);
102 #ifdef CCAN_TIMER_DEBUG
106 * timers_dump - dump the timers datastructure (for debugging it)
107 * @t: the struct timers
108 * @fp: the FILE to dump to (stderr if @fp is NULL)
110 void timers_dump(const struct timers *timers, FILE *fp);
114 * struct timers - structure to hold a set of timers.
116 * Initialized using timers_init, the levels of the timer are
117 * allocated as necessary, using malloc.
120 * timers_init(), timers_cleanup()
123 /* Far in the future. */
124 struct list_head far;
128 struct timer_level *level[(64 + TIMER_LEVEL_BITS-1) / TIMER_LEVEL_BITS];
132 * struct timer - a single timer.
134 * Set up by timer_add(), this is usually contained within an
135 * application-specific structure.
138 * ccan/container_of, timer_add(), timer_del()
141 struct list_node list;
144 #endif /* CCAN_TIMER_H */