common events code for timed events
Copyright (C) Andrew Tridgell 2003-2006
- Copyright (C) Stefan Metzmacher 2005
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 3 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
+ Copyright (C) Stefan Metzmacher 2005-2009
+
+ ** NOTE! The following LGPL license applies to the tevent
+ ** library. This does NOT imply that all of Samba is released
+ ** under the LGPL
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 3 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "replace.h"
Return 0 if tv1 == tv2
Return 1 if tv1 > tv2
*/
-static int ev_timeval_compare(const struct timeval *tv1, const struct timeval *tv2)
+int tevent_timeval_compare(const struct timeval *tv1, const struct timeval *tv2)
{
if (tv1->tv_sec > tv2->tv_sec) return 1;
if (tv1->tv_sec < tv2->tv_sec) return -1;
/**
return a zero timeval
*/
-static struct timeval ev_timeval_zero(void)
+struct timeval tevent_timeval_zero(void)
{
struct timeval tv;
tv.tv_sec = 0;
/**
return a timeval for the current time
*/
-static struct timeval ev_timeval_current(void)
+struct timeval tevent_timeval_current(void)
{
struct timeval tv;
gettimeofday(&tv, NULL);
/**
return a timeval struct with the given elements
*/
-static struct timeval ev_timeval_set(uint32_t secs, uint32_t usecs)
+struct timeval tevent_timeval_set(uint32_t secs, uint32_t usecs)
{
struct timeval tv;
tv.tv_sec = secs;
if tv1 comes after tv2, then return a zero timeval
(this is *tv2 - *tv1)
*/
-static struct timeval ev_timeval_until(const struct timeval *tv1,
- const struct timeval *tv2)
+struct timeval tevent_timeval_until(const struct timeval *tv1,
+ const struct timeval *tv2)
{
struct timeval t;
- if (ev_timeval_compare(tv1, tv2) >= 0) {
- return ev_timeval_zero();
+ if (tevent_timeval_compare(tv1, tv2) >= 0) {
+ return tevent_timeval_zero();
}
t.tv_sec = tv2->tv_sec - tv1->tv_sec;
if (tv1->tv_usec > tv2->tv_usec) {
/**
return true if a timeval is zero
*/
-bool ev_timeval_is_zero(const struct timeval *tv)
+bool tevent_timeval_is_zero(const struct timeval *tv)
{
return tv->tv_sec == 0 && tv->tv_usec == 0;
}
+struct timeval tevent_timeval_add(const struct timeval *tv, uint32_t secs,
+ uint32_t usecs)
+{
+ struct timeval tv2 = *tv;
+ tv2.tv_sec += secs;
+ tv2.tv_usec += usecs;
+ tv2.tv_sec += tv2.tv_usec / 1000000;
+ tv2.tv_usec = tv2.tv_usec % 1000000;
+
+ return tv2;
+}
+
+/**
+ return a timeval in the future with a specified offset
+*/
+struct timeval tevent_timeval_current_ofs(uint32_t secs, uint32_t usecs)
+{
+ struct timeval tv = tevent_timeval_current();
+ return tevent_timeval_add(&tv, secs, usecs);
+}
+
/*
destroy a timed event
*/
static int tevent_common_timed_destructor(struct tevent_timer *te)
{
- if (te->event_ctx) {
- DLIST_REMOVE(te->event_ctx->timer_events, te);
+ if (te->destroyed) {
+ tevent_common_check_double_free(te, "tevent_timer double free");
+ goto done;
}
+ te->destroyed = true;
+
+ if (te->event_ctx == NULL) {
+ return 0;
+ }
+
+ tevent_debug(te->event_ctx, TEVENT_DEBUG_TRACE,
+ "Destroying timer event %p \"%s\"\n",
+ te, te->handler_name);
+
+ if (te->event_ctx->last_zero_timer == te) {
+ te->event_ctx->last_zero_timer = DLIST_PREV(te);
+ }
+ DLIST_REMOVE(te->event_ctx->timer_events, te);
+
+ te->event_ctx = NULL;
+
+done:
+ if (te->busy) {
+ return -1;
+ }
+
return 0;
}
-static int tevent_common_timed_deny_destructor(struct tevent_timer *te)
+static void tevent_common_insert_timer(struct tevent_context *ev,
+ struct tevent_timer *te,
+ bool optimize_zero)
{
- return -1;
+ struct tevent_timer *prev_te = NULL;
+
+ if (te->destroyed) {
+ tevent_abort(ev, "tevent_timer use after free");
+ return;
+ }
+
+ /* keep the list ordered */
+ if (optimize_zero && tevent_timeval_is_zero(&te->next_event)) {
+ /*
+ * Some callers use zero tevent_timer
+ * instead of tevent_immediate events.
+ *
+ * As these can happen very often,
+ * we remember the last zero timer
+ * in the list.
+ */
+ prev_te = ev->last_zero_timer;
+ ev->last_zero_timer = te;
+ } else {
+ struct tevent_timer *cur_te;
+
+ /*
+ * we traverse the list from the tail
+ * because it's much more likely that
+ * timers are added at the end of the list
+ */
+ for (cur_te = DLIST_TAIL(ev->timer_events);
+ cur_te != NULL;
+ cur_te = DLIST_PREV(cur_te))
+ {
+ int ret;
+
+ /*
+ * if the new event comes before the current
+ * we continue searching
+ */
+ ret = tevent_timeval_compare(&te->next_event,
+ &cur_te->next_event);
+ if (ret < 0) {
+ continue;
+ }
+
+ break;
+ }
+
+ prev_te = cur_te;
+ }
+
+ DLIST_ADD_AFTER(ev->timer_events, te, prev_te);
}
/*
add a timed event
return NULL on failure (memory allocation error)
*/
-struct tevent_timer *tevent_common_add_timer(struct tevent_context *ev, TALLOC_CTX *mem_ctx,
+static struct tevent_timer *tevent_common_add_timer_internal(
+ struct tevent_context *ev,
+ TALLOC_CTX *mem_ctx,
+ struct timeval next_event,
+ tevent_timer_handler_t handler,
+ void *private_data,
+ const char *handler_name,
+ const char *location,
+ bool optimize_zero)
+{
+ struct tevent_timer *te;
+
+ te = talloc(mem_ctx?mem_ctx:ev, struct tevent_timer);
+ if (te == NULL) return NULL;
+
+ *te = (struct tevent_timer) {
+ .event_ctx = ev,
+ .next_event = next_event,
+ .handler = handler,
+ .private_data = private_data,
+ .handler_name = handler_name,
+ .location = location,
+ };
+
+ if (ev->timer_events == NULL) {
+ ev->last_zero_timer = NULL;
+ }
+
+ tevent_common_insert_timer(ev, te, optimize_zero);
+
+ talloc_set_destructor(te, tevent_common_timed_destructor);
+
+ tevent_debug(ev, TEVENT_DEBUG_TRACE,
+ "Added timed event \"%s\": %p\n",
+ handler_name, te);
+ return te;
+}
+
+struct tevent_timer *tevent_common_add_timer(struct tevent_context *ev,
+ TALLOC_CTX *mem_ctx,
struct timeval next_event,
tevent_timer_handler_t handler,
void *private_data,
const char *handler_name,
const char *location)
{
- struct tevent_timer *te, *last_te, *cur_te;
+ /*
+ * do not use optimization, there are broken Samba
+ * versions which use tevent_common_add_timer()
+ * without using tevent_common_loop_timer_delay(),
+ * it just uses DLIST_REMOVE(ev->timer_events, te)
+ * and would leave ev->last_zero_timer behind.
+ */
+ return tevent_common_add_timer_internal(ev, mem_ctx, next_event,
+ handler, private_data,
+ handler_name, location,
+ false);
+}
- te = talloc(mem_ctx?mem_ctx:ev, struct tevent_timer);
- if (te == NULL) return NULL;
+struct tevent_timer *tevent_common_add_timer_v2(struct tevent_context *ev,
+ TALLOC_CTX *mem_ctx,
+ struct timeval next_event,
+ tevent_timer_handler_t handler,
+ void *private_data,
+ const char *handler_name,
+ const char *location)
+{
+ /*
+ * Here we turn on last_zero_timer optimization
+ */
+ return tevent_common_add_timer_internal(ev, mem_ctx, next_event,
+ handler, private_data,
+ handler_name, location,
+ true);
+}
- te->event_ctx = ev;
- te->next_event = next_event;
- te->handler = handler;
- te->private_data = private_data;
- te->handler_name = handler_name;
- te->location = location;
- te->additional_data = NULL;
+void tevent_update_timer(struct tevent_timer *te, struct timeval next_event)
+{
+ struct tevent_context *ev = te->event_ctx;
- /* keep the list ordered */
- last_te = NULL;
- for (cur_te = ev->timer_events; cur_te; cur_te = cur_te->next) {
- /* if the new event comes before the current one break */
- if (ev_timeval_compare(&te->next_event, &cur_te->next_event) < 0) {
- break;
- }
+ if (ev->last_zero_timer == te) {
+ te->event_ctx->last_zero_timer = DLIST_PREV(te);
+ }
+ DLIST_REMOVE(ev->timer_events, te);
+
+ te->next_event = next_event;
- last_te = cur_te;
+ /*
+ * Not doing the zero_timer optimization. This is for new code
+ * that should know about immediates.
+ */
+ tevent_common_insert_timer(ev, te, false);
+}
+
+_PRIVATE_
+int tevent_common_invoke_timer_handler(struct tevent_timer *te,
+ struct timeval current_time,
+ bool *removed)
+{
+ if (removed != NULL) {
+ *removed = false;
}
- DLIST_ADD_AFTER(ev->timer_events, te, last_te);
+ if (te->event_ctx == NULL) {
+ return 0;
+ }
- talloc_set_destructor(te, tevent_common_timed_destructor);
+ /*
+ * We need to remove the timer from the list before calling the
+ * handler because in a semi-async inner event loop called from the
+ * handler we don't want to come across this event again -- vl
+ */
+ if (te->event_ctx->last_zero_timer == te) {
+ te->event_ctx->last_zero_timer = DLIST_PREV(te);
+ }
+ DLIST_REMOVE(te->event_ctx->timer_events, te);
- return te;
-}
+ tevent_debug(te->event_ctx, TEVENT_DEBUG_TRACE,
+ "Running timer event %p \"%s\"\n",
+ te, te->handler_name);
+ /*
+ * If the timed event was registered for a zero current_time,
+ * then we pass a zero timeval here too! To avoid the
+ * overhead of gettimeofday() calls.
+ *
+ * otherwise we pass the current time
+ */
+ te->busy = true;
+ te->handler(te->event_ctx, te, current_time, te->private_data);
+ te->busy = false;
+
+ tevent_debug(te->event_ctx, TEVENT_DEBUG_TRACE,
+ "Ending timer event %p \"%s\"\n",
+ te, te->handler_name);
+
+ te->event_ctx = NULL;
+ talloc_set_destructor(te, NULL);
+ TALLOC_FREE(te);
+
+ if (removed != NULL) {
+ *removed = true;
+ }
+
+ return 0;
+}
/*
do a single event loop using the events defined in ev
- return the delay untill the next timed event,
+ return the delay until the next timed event,
or zero if a timed event was triggered
*/
struct timeval tevent_common_loop_timer_delay(struct tevent_context *ev)
{
- struct timeval current_time = ev_timeval_zero();
+ struct timeval current_time = tevent_timeval_zero();
struct tevent_timer *te = ev->timer_events;
+ int ret;
if (!te) {
/* have a default tick time of 30 seconds. This guarantees
that code that uses its own timeout checking will be
- able to proceeed eventually */
- return ev_timeval_set(30, 0);
+ able to proceed eventually */
+ return tevent_timeval_set(30, 0);
}
/*
* if there's a delay till the next timed event, we're done
* with just returning the delay
*/
- if (!ev_timeval_is_zero(&te->next_event)) {
+ if (!tevent_timeval_is_zero(&te->next_event)) {
struct timeval delay;
- current_time = ev_timeval_current();
+ current_time = tevent_timeval_current();
- delay = ev_timeval_until(¤t_time, &te->next_event);
- if (!ev_timeval_is_zero(&delay)) {
+ delay = tevent_timeval_until(¤t_time, &te->next_event);
+ if (!tevent_timeval_is_zero(&delay)) {
return delay;
}
}
/*
* ok, we have a timed event that we'll process ...
*/
+ ret = tevent_common_invoke_timer_handler(te, current_time, NULL);
+ if (ret != 0) {
+ tevent_abort(ev, "tevent_common_invoke_timer_handler() failed");
+ }
- /* deny the handler to free the event */
- talloc_set_destructor(te, tevent_common_timed_deny_destructor);
-
- /* We need to remove the timer from the list before calling the
- * handler because in a semi-async inner event loop called from the
- * handler we don't want to come across this event again -- vl */
- DLIST_REMOVE(ev->timer_events, te);
-
- /*
- * If the timed event was registered for a zero current_time,
- * then we pass a zero timeval here too! To avoid the
- * overhead of gettimeofday() calls.
- *
- * otherwise we pass the current time
- */
- te->handler(ev, te, current_time, te->private_data);
-
- /* The destructor isn't necessary anymore, we've already removed the
- * event from the list. */
- talloc_set_destructor(te, NULL);
-
- talloc_free(te);
-
- return ev_timeval_zero();
+ return tevent_timeval_zero();
}
git.samba.org / metze / samba / wip.git / blobdiff