Adding upstream version 0.16.1.upstream/0.16.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 477 insertions, 0 deletions

diff --git a/tevent_timed.c b/tevent_timed.c
new file mode 100644
index 0000000..b4a2498
--- /dev/null
+++ b/tevent_timed.c
@@ -0,0 +1,477 @@
+/*
+   Unix SMB/CIFS implementation.
+
+   common events code for timed events
+
+   Copyright (C) Andrew Tridgell	2003-2006
+   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
+   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"
+#include "system/time.h"
+#define TEVENT_DEPRECATED 1
+#include "tevent.h"
+#include "tevent_internal.h"
+#include "tevent_util.h"
+
+/**
+  compare two timeval structures.
+  Return -1 if tv1 < tv2
+  Return 0 if tv1 == tv2
+  Return 1 if tv1 > 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;
+	if (tv1->tv_usec > tv2->tv_usec) return 1;
+	if (tv1->tv_usec < tv2->tv_usec) return -1;
+	return 0;
+}
+
+/**
+  return a zero timeval
+*/
+struct timeval tevent_timeval_zero(void)
+{
+	struct timeval tv;
+	tv.tv_sec = 0;
+	tv.tv_usec = 0;
+	return tv;
+}
+
+/**
+  return a timeval for the current time
+*/
+struct timeval tevent_timeval_current(void)
+{
+	struct timeval tv;
+	gettimeofday(&tv, NULL);
+	return tv;
+}
+
+/**
+  return a timeval struct with the given elements
+*/
+struct timeval tevent_timeval_set(uint32_t secs, uint32_t usecs)
+{
+	struct timeval tv;
+	tv.tv_sec = secs;
+	tv.tv_usec = usecs;
+	return tv;
+}
+
+/**
+  return the difference between two timevals as a timeval
+  if tv1 comes after tv2, then return a zero timeval
+  (this is *tv2 - *tv1)
+*/
+struct timeval tevent_timeval_until(const struct timeval *tv1,
+				    const struct timeval *tv2)
+{
+	struct timeval t;
+	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) {
+		t.tv_sec--;
+		t.tv_usec = 1000000 - (tv1->tv_usec - tv2->tv_usec);
+	} else {
+		t.tv_usec = tv2->tv_usec - tv1->tv_usec;
+	}
+	return t;
+}
+
+/**
+  return true if a timeval is zero
+*/
+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->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);
+	}
+
+	tevent_trace_timer_callback(te->event_ctx, te, TEVENT_EVENT_TRACE_DETACH);
+	DLIST_REMOVE(te->event_ctx->timer_events, te);
+
+	te->event_ctx = NULL;
+done:
+	if (te->busy) {
+		return -1;
+	}
+	te->wrapper = NULL;
+
+	return 0;
+}
+
+static void tevent_common_insert_timer(struct tevent_context *ev,
+				       struct tevent_timer *te,
+				       bool optimize_zero)
+{
+	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;
+	}
+
+	tevent_trace_timer_callback(te->event_ctx, te, TEVENT_EVENT_TRACE_ATTACH);
+	DLIST_ADD_AFTER(ev->timer_events, te, prev_te);
+}
+
+/*
+  add a timed event
+  return NULL on failure (memory allocation error)
+*/
+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)
+{
+	/*
+	 * 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);
+}
+
+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);
+}
+
+void tevent_update_timer(struct tevent_timer *te, struct timeval next_event)
+{
+	struct tevent_context *ev = te->event_ctx;
+
+	if (ev->last_zero_timer == te) {
+		te->event_ctx->last_zero_timer = DLIST_PREV(te);
+	}
+	tevent_trace_timer_callback(te->event_ctx, te, TEVENT_EVENT_TRACE_DETACH);
+	DLIST_REMOVE(ev->timer_events, te);
+
+	te->next_event = next_event;
+
+	/*
+	 * Not doing the zero_timer optimization. This is for new code
+	 * that should know about immediates.
+	 */
+	tevent_common_insert_timer(ev, te, false);
+}
+
+int tevent_common_invoke_timer_handler(struct tevent_timer *te,
+				       struct timeval current_time,
+				       bool *removed)
+{
+	struct tevent_context *handler_ev = te->event_ctx;
+
+	if (removed != NULL) {
+		*removed = false;
+	}
+
+	if (te->event_ctx == NULL) {
+		return 0;
+	}
+
+	/*
+	 * 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);
+
+	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;
+	if (te->wrapper != NULL) {
+		handler_ev = te->wrapper->wrap_ev;
+
+		tevent_wrapper_push_use_internal(handler_ev, te->wrapper);
+		te->wrapper->ops->before_timer_handler(
+					te->wrapper->wrap_ev,
+					te->wrapper->private_state,
+					te->wrapper->main_ev,
+					te,
+					te->next_event,
+					current_time,
+					te->handler_name,
+					te->location);
+	}
+	tevent_trace_timer_callback(te->event_ctx, te, TEVENT_EVENT_TRACE_BEFORE_HANDLER);
+	te->handler(handler_ev, te, current_time, te->private_data);
+	if (te->wrapper != NULL) {
+		te->wrapper->ops->after_timer_handler(
+					te->wrapper->wrap_ev,
+					te->wrapper->private_state,
+					te->wrapper->main_ev,
+					te,
+					te->next_event,
+					current_time,
+					te->handler_name,
+					te->location);
+		tevent_wrapper_pop_use_internal(handler_ev, te->wrapper);
+	}
+	te->busy = false;
+
+	TEVENT_DEBUG(te->event_ctx, TEVENT_DEBUG_TRACE,
+		     "Ending timer event %p \"%s\"\n",
+		     te, te->handler_name);
+
+	/* The callback was already called when freed from the handler. */
+	if (!te->destroyed) {
+		tevent_trace_timer_callback(te->event_ctx, te, TEVENT_EVENT_TRACE_DETACH);
+	}
+
+	te->wrapper = NULL;
+	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 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 = 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 proceed eventually */
+		return tevent_timeval_set(30, 0);
+	}
+
+	/*
+	 * work out the right timeout for the next timed event
+	 *
+	 * avoid the syscall to gettimeofday() if the timed event should
+	 * be triggered directly
+	 *
+	 * if there's a delay till the next timed event, we're done
+	 * with just returning the delay
+	 */
+	if (!tevent_timeval_is_zero(&te->next_event)) {
+		struct timeval delay;
+
+		current_time = tevent_timeval_current();
+
+		delay = tevent_timeval_until(&current_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");
+	}
+
+	return tevent_timeval_zero();
+}
+
+void tevent_timer_set_tag(struct tevent_timer *te, uint64_t tag)
+{
+	if (te == NULL) {
+		return;
+	}
+
+	te->tag = tag;
+}
+
+uint64_t tevent_timer_get_tag(const struct tevent_timer *te)
+{
+	if (te == NULL) {
+		return 0;
+	}
+
+	return te->tag;
+}