2 Unix SMB/CIFS implementation.
4 common events code for timed events
6 Copyright (C) Andrew Tridgell 2003-2006
7 Copyright (C) Stefan Metzmacher 2005
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>.
26 #include "system/filesys.h"
27 #include "system/select.h"
29 #include "events_internal.h"
32 compare two timeval structures.
33 Return -1 if tv1 < tv2
34 Return 0 if tv1 == tv2
37 static int ev_timeval_compare(const struct timeval *tv1, const struct timeval *tv2)
39 if (tv1->tv_sec > tv2->tv_sec) return 1;
40 if (tv1->tv_sec < tv2->tv_sec) return -1;
41 if (tv1->tv_usec > tv2->tv_usec) return 1;
42 if (tv1->tv_usec < tv2->tv_usec) return -1;
49 static struct timeval ev_timeval_zero(void)
58 return a timeval for the current time
60 static struct timeval ev_timeval_current(void)
63 gettimeofday(&tv, NULL);
68 return a timeval struct with the given elements
70 static struct timeval ev_timeval_set(uint32_t secs, uint32_t usecs)
79 return the difference between two timevals as a timeval
80 if tv1 comes after tv2, then return a zero timeval
83 static struct timeval ev_timeval_until(const struct timeval *tv1,
84 const struct timeval *tv2)
87 if (ev_timeval_compare(tv1, tv2) >= 0) {
88 return ev_timeval_zero();
90 t.tv_sec = tv2->tv_sec - tv1->tv_sec;
91 if (tv1->tv_usec > tv2->tv_usec) {
93 t.tv_usec = 1000000 - (tv1->tv_usec - tv2->tv_usec);
95 t.tv_usec = tv2->tv_usec - tv1->tv_usec;
101 return true if a timeval is zero
103 bool ev_timeval_is_zero(const struct timeval *tv)
105 return tv->tv_sec == 0 && tv->tv_usec == 0;
109 destroy a timed event
111 static int common_event_timed_destructor(struct timed_event *te)
113 struct event_context *ev = talloc_get_type(te->event_ctx,
114 struct event_context);
115 DLIST_REMOVE(ev->timed_events, te);
119 static int common_event_timed_deny_destructor(struct timed_event *te)
126 return NULL on failure (memory allocation error)
128 struct timed_event *common_event_add_timed(struct event_context *ev, TALLOC_CTX *mem_ctx,
129 struct timeval next_event,
130 event_timed_handler_t handler,
133 struct timed_event *te, *last_te, *cur_te;
135 te = talloc(mem_ctx?mem_ctx:ev, struct timed_event);
136 if (te == NULL) return NULL;
139 te->next_event = next_event;
140 te->handler = handler;
141 te->private_data = private_data;
142 te->additional_data = NULL;
144 /* keep the list ordered */
146 for (cur_te = ev->timed_events; cur_te; cur_te = cur_te->next) {
147 /* if the new event comes before the current one break */
148 if (ev_timeval_compare(&te->next_event, &cur_te->next_event) < 0) {
155 DLIST_ADD_AFTER(ev->timed_events, te, last_te);
157 talloc_set_destructor(te, common_event_timed_destructor);
163 do a single event loop using the events defined in ev
165 return the delay untill the next timed event,
166 or zero if a timed event was triggered
168 struct timeval common_event_loop_timer_delay(struct event_context *ev)
170 struct timeval current_time = ev_timeval_zero();
171 struct timed_event *te = ev->timed_events;
174 /* have a default tick time of 30 seconds. This guarantees
175 that code that uses its own timeout checking will be
176 able to proceeed eventually */
177 return ev_timeval_set(30, 0);
181 * work out the right timeout for the next timed event
183 * avoid the syscall to gettimeofday() if the timed event should
184 * be triggered directly
186 * if there's a delay till the next timed event, we're done
187 * with just returning the delay
189 if (!ev_timeval_is_zero(&te->next_event)) {
190 struct timeval delay;
192 current_time = ev_timeval_current();
194 delay = ev_timeval_until(¤t_time, &te->next_event);
195 if (!ev_timeval_is_zero(&delay)) {
201 * ok, we have a timed event that we'll process ...
204 /* deny the handler to free the event */
205 talloc_set_destructor(te, common_event_timed_deny_destructor);
207 /* We need to remove the timer from the list before calling the
208 * handler because in a semi-async inner event loop called from the
209 * handler we don't want to come across this event again -- vl */
210 DLIST_REMOVE(ev->timed_events, te);
213 * If the timed event was registered for a zero current_time,
214 * then we pass a zero timeval here too! To avoid the
215 * overhead of gettimeofday() calls.
217 * otherwise we pass the current time
219 te->handler(ev, te, current_time, te->private_data);
221 /* The destructor isn't necessary anymore, we've already removed the
222 * event from the list. */
223 talloc_set_destructor(te, NULL);
227 return ev_timeval_zero();