Just import libevent, with minor tweaks as described in README.google

A second changelist will actually use it
Split because otherwise it's hard to review the second part.


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@2345 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 1012 insertions, 0 deletions

diff --git a/third_party/libevent/event.c b/third_party/libevent/event.c
new file mode 100644
index 0000000..3396b35
--- /dev/null
+++ b/third_party/libevent/event.c
@@ -0,0 +1,1012 @@
+/*
+ * Copyright (c) 2000-2004 Niels Provos <provos@citi.umich.edu>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#ifdef WIN32
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#undef WIN32_LEAN_AND_MEAN
+#endif
+#include <sys/types.h>
+#ifdef HAVE_SYS_TIME_H
+#include <sys/time.h>
+#else 
+#include <sys/_time.h>
+#endif
+#include <sys/queue.h>
+#include <stdio.h>
+#include <stdlib.h>
+#ifndef WIN32
+#include <unistd.h>
+#endif
+#include <errno.h>
+#include <signal.h>
+#include <string.h>
+#include <assert.h>
+#include <time.h>
+
+#include "event.h"
+#include "event-internal.h"
+#include "evutil.h"
+#include "log.h"
+
+#ifdef HAVE_EVENT_PORTS
+extern const struct eventop evportops;
+#endif
+#ifdef HAVE_SELECT
+extern const struct eventop selectops;
+#endif
+#ifdef HAVE_POLL
+extern const struct eventop pollops;
+#endif
+#ifdef HAVE_EPOLL
+extern const struct eventop epollops;
+#endif
+#ifdef HAVE_WORKING_KQUEUE
+extern const struct eventop kqops;
+#endif
+#ifdef HAVE_DEVPOLL
+extern const struct eventop devpollops;
+#endif
+#ifdef WIN32
+extern const struct eventop win32ops;
+#endif
+
+/* In order of preference */
+const struct eventop *eventops[] = {
+#ifdef HAVE_EVENT_PORTS
+	&evportops,
+#endif
+#ifdef HAVE_WORKING_KQUEUE
+	&kqops,
+#endif
+#ifdef HAVE_EPOLL
+	&epollops,
+#endif
+#ifdef HAVE_DEVPOLL
+	&devpollops,
+#endif
+#ifdef HAVE_POLL
+	&pollops,
+#endif
+#ifdef HAVE_SELECT
+	&selectops,
+#endif
+#ifdef WIN32
+	&win32ops,
+#endif
+	NULL
+};
+
+/* Global state */
+struct event_base *current_base = NULL;
+extern struct event_base *evsignal_base;
+static int use_monotonic;
+
+/* Handle signals - This is a deprecated interface */
+int (*event_sigcb)(void);		/* Signal callback when gotsig is set */
+volatile sig_atomic_t event_gotsig;	/* Set in signal handler */
+
+/* Prototypes */
+static void	event_queue_insert(struct event_base *, struct event *, int);
+static void	event_queue_remove(struct event_base *, struct event *, int);
+static int	event_haveevents(struct event_base *);
+
+static void	event_process_active(struct event_base *);
+
+static int	timeout_next(struct event_base *, struct timeval **);
+static void	timeout_process(struct event_base *);
+static void	timeout_correct(struct event_base *, struct timeval *);
+
+static void
+detect_monotonic(void)
+{
+#if defined(HAVE_CLOCK_GETTIME) && defined(CLOCK_MONOTONIC)
+	struct timespec	ts;
+
+	if (clock_gettime(CLOCK_MONOTONIC, &ts) == 0)
+		use_monotonic = 1;
+#endif
+}
+
+static int
+gettime(struct event_base *base, struct timeval *tp)
+{
+	if (base->tv_cache.tv_sec) {
+		*tp = base->tv_cache;
+		return (0);
+	}
+
+#if defined(HAVE_CLOCK_GETTIME) && defined(CLOCK_MONOTONIC)
+	if (use_monotonic) {
+		struct timespec	ts;
+
+		if (clock_gettime(CLOCK_MONOTONIC, &ts) == -1)
+			return (-1);
+
+		tp->tv_sec = ts.tv_sec;
+		tp->tv_usec = ts.tv_nsec / 1000;
+		return (0);
+	}
+#endif
+
+	return (evutil_gettimeofday(tp, NULL));
+}
+
+struct event_base *
+event_init(void)
+{
+	struct event_base *base = event_base_new();
+
+	if (base != NULL)
+		current_base = base;
+
+	return (base);
+}
+
+struct event_base *
+event_base_new(void)
+{
+	int i;
+	struct event_base *base;
+
+	if ((base = calloc(1, sizeof(struct event_base))) == NULL)
+		event_err(1, "%s: calloc", __func__);
+
+	event_sigcb = NULL;
+	event_gotsig = 0;
+
+	detect_monotonic();
+	gettime(base, &base->event_tv);
+	
+	min_heap_ctor(&base->timeheap);
+	TAILQ_INIT(&base->eventqueue);
+	base->sig.ev_signal_pair[0] = -1;
+	base->sig.ev_signal_pair[1] = -1;
+	
+	base->evbase = NULL;
+	for (i = 0; eventops[i] && !base->evbase; i++) {
+		base->evsel = eventops[i];
+
+		base->evbase = base->evsel->init(base);
+	}
+
+	if (base->evbase == NULL)
+		event_errx(1, "%s: no event mechanism available", __func__);
+
+	if (getenv("EVENT_SHOW_METHOD")) 
+		event_msgx("libevent using: %s\n",
+			   base->evsel->name);
+
+	/* allocate a single active event queue */
+	event_base_priority_init(base, 1);
+
+	return (base);
+}
+
+void
+event_base_free(struct event_base *base)
+{
+	int i, n_deleted=0;
+	struct event *ev;
+
+	if (base == NULL && current_base)
+		base = current_base;
+	if (base == current_base)
+		current_base = NULL;
+
+	/* XXX(niels) - check for internal events first */
+	assert(base);
+	/* Delete all non-internal events. */
+	for (ev = TAILQ_FIRST(&base->eventqueue); ev; ) {
+		struct event *next = TAILQ_NEXT(ev, ev_next);
+		if (!(ev->ev_flags & EVLIST_INTERNAL)) {
+			event_del(ev);
+			++n_deleted;
+		}
+		ev = next;
+	}
+	while ((ev = min_heap_top(&base->timeheap)) != NULL) {
+		event_del(ev);
+		++n_deleted;
+	}
+
+	for (i = 0; i < base->nactivequeues; ++i) {
+		for (ev = TAILQ_FIRST(base->activequeues[i]); ev; ) {
+			struct event *next = TAILQ_NEXT(ev, ev_active_next);
+			if (!(ev->ev_flags & EVLIST_INTERNAL)) {
+				event_del(ev);
+				++n_deleted;
+			}
+			ev = next;
+		}
+	}
+
+	if (n_deleted)
+		event_debug(("%s: %d events were still set in base",
+			__func__, n_deleted));
+
+	if (base->evsel->dealloc != NULL)
+		base->evsel->dealloc(base, base->evbase);
+
+	for (i = 0; i < base->nactivequeues; ++i)
+		assert(TAILQ_EMPTY(base->activequeues[i]));
+
+	assert(min_heap_empty(&base->timeheap));
+	min_heap_dtor(&base->timeheap);
+
+	for (i = 0; i < base->nactivequeues; ++i)
+		free(base->activequeues[i]);
+	free(base->activequeues);
+
+	assert(TAILQ_EMPTY(&base->eventqueue));
+
+	free(base);
+}
+
+/* reinitialized the event base after a fork */
+int
+event_reinit(struct event_base *base)
+{
+	const struct eventop *evsel = base->evsel;
+	void *evbase = base->evbase;
+	int res = 0;
+	struct event *ev;
+
+	/* check if this event mechanism requires reinit */
+	if (!evsel->need_reinit)
+		return (0);
+
+	/* prevent internal delete */
+	if (base->sig.ev_signal_added) {
+		event_queue_remove(base, &base->sig.ev_signal,
+		    EVLIST_INSERTED);
+		base->sig.ev_signal_added = 0;
+	}
+	
+	if (base->evsel->dealloc != NULL)
+		base->evsel->dealloc(base, base->evbase);
+	evbase = base->evbase = evsel->init(base);
+	if (base->evbase == NULL)
+		event_errx(1, "%s: could not reinitialize event mechanism",
+		    __func__);
+
+	TAILQ_FOREACH(ev, &base->eventqueue, ev_next) {
+		if (evsel->add(evbase, ev) == -1)
+			res = -1;
+	}
+
+	return (res);
+}
+
+int
+event_priority_init(int npriorities)
+{
+  return event_base_priority_init(current_base, npriorities);
+}
+
+int
+event_base_priority_init(struct event_base *base, int npriorities)
+{
+	int i;
+
+	if (base->event_count_active)
+		return (-1);
+
+	if (base->nactivequeues && npriorities != base->nactivequeues) {
+		for (i = 0; i < base->nactivequeues; ++i) {
+			free(base->activequeues[i]);
+		}
+		free(base->activequeues);
+	}
+
+	/* Allocate our priority queues */
+	base->nactivequeues = npriorities;
+	base->activequeues = (struct event_list **)calloc(base->nactivequeues,
+	    npriorities * sizeof(struct event_list *));
+	if (base->activequeues == NULL)
+		event_err(1, "%s: calloc", __func__);
+
+	for (i = 0; i < base->nactivequeues; ++i) {
+		base->activequeues[i] = malloc(sizeof(struct event_list));
+		if (base->activequeues[i] == NULL)
+			event_err(1, "%s: malloc", __func__);
+		TAILQ_INIT(base->activequeues[i]);
+	}
+
+	return (0);
+}
+
+int
+event_haveevents(struct event_base *base)
+{
+	return (base->event_count > 0);
+}
+
+/*
+ * Active events are stored in priority queues.  Lower priorities are always
+ * process before higher priorities.  Low priority events can starve high
+ * priority ones.
+ */
+
+static void
+event_process_active(struct event_base *base)
+{
+	struct event *ev;
+	struct event_list *activeq = NULL;
+	int i;
+	short ncalls;
+
+	for (i = 0; i < base->nactivequeues; ++i) {
+		if (TAILQ_FIRST(base->activequeues[i]) != NULL) {
+			activeq = base->activequeues[i];
+			break;
+		}
+	}
+
+	assert(activeq != NULL);
+
+	for (ev = TAILQ_FIRST(activeq); ev; ev = TAILQ_FIRST(activeq)) {
+		if (ev->ev_events & EV_PERSIST)
+			event_queue_remove(base, ev, EVLIST_ACTIVE);
+		else
+			event_del(ev);
+		
+		/* Allows deletes to work */
+		ncalls = ev->ev_ncalls;
+		ev->ev_pncalls = &ncalls;
+		while (ncalls) {
+			ncalls--;
+			ev->ev_ncalls = ncalls;
+			(*ev->ev_callback)((int)ev->ev_fd, ev->ev_res, ev->ev_arg);
+			if (event_gotsig || base->event_break)
+				return;
+		}
+	}
+}
+
+/*
+ * Wait continously for events.  We exit only if no events are left.
+ */
+
+int
+event_dispatch(void)
+{
+	return (event_loop(0));
+}
+
+int
+event_base_dispatch(struct event_base *event_base)
+{
+  return (event_base_loop(event_base, 0));
+}
+
+const char *
+event_base_get_method(struct event_base *base)
+{
+	assert(base);
+	return (base->evsel->name);
+}
+
+static void
+event_loopexit_cb(int fd, short what, void *arg)
+{
+	struct event_base *base = arg;
+	base->event_gotterm = 1;
+}
+
+/* not thread safe */
+int
+event_loopexit(const struct timeval *tv)
+{
+	return (event_once(-1, EV_TIMEOUT, event_loopexit_cb,
+		    current_base, tv));
+}
+
+int
+event_base_loopexit(struct event_base *event_base, const struct timeval *tv)
+{
+	return (event_base_once(event_base, -1, EV_TIMEOUT, event_loopexit_cb,
+		    event_base, tv));
+}
+
+/* not thread safe */
+int
+event_loopbreak(void)
+{
+	return (event_base_loopbreak(current_base));
+}
+
+int
+event_base_loopbreak(struct event_base *event_base)
+{
+	if (event_base == NULL)
+		return (-1);
+
+	event_base->event_break = 1;
+	return (0);
+}
+
+
+
+/* not thread safe */
+
+int
+event_loop(int flags)
+{
+	return event_base_loop(current_base, flags);
+}
+
+int
+event_base_loop(struct event_base *base, int flags)
+{
+	const struct eventop *evsel = base->evsel;
+	void *evbase = base->evbase;
+	struct timeval tv;
+	struct timeval *tv_p;
+	int res, done;
+
+	if (&base->sig.ev_signal_added)
+		evsignal_base = base;
+	done = 0;
+	while (!done) {
+		/* Terminate the loop if we have been asked to */
+		if (base->event_gotterm) {
+			base->event_gotterm = 0;
+			break;
+		}
+
+		if (base->event_break) {
+			base->event_break = 0;
+			break;
+		}
+
+		/* You cannot use this interface for multi-threaded apps */
+		while (event_gotsig) {
+			event_gotsig = 0;
+			if (event_sigcb) {
+				res = (*event_sigcb)();
+				if (res == -1) {
+					errno = EINTR;
+					return (-1);
+				}
+			}
+		}
+
+		timeout_correct(base, &tv);
+
+		tv_p = &tv;
+		if (!base->event_count_active && !(flags & EVLOOP_NONBLOCK)) {
+			timeout_next(base, &tv_p);
+		} else {
+			/* 
+			 * if we have active events, we just poll new events
+			 * without waiting.
+			 */
+			evutil_timerclear(&tv);
+		}
+		
+		/* If we have no events, we just exit */
+		if (!event_haveevents(base)) {
+			event_debug(("%s: no events registered.", __func__));
+			return (1);
+		}
+
+		/* update last old time */
+		gettime(base, &base->event_tv);
+
+		/* clear time cache */
+		base->tv_cache.tv_sec = 0;
+
+		res = evsel->dispatch(base, evbase, tv_p);
+
+		if (res == -1)
+			return (-1);
+		gettime(base, &base->tv_cache);
+
+		timeout_process(base);
+
+		if (base->event_count_active) {
+			event_process_active(base);
+			if (!base->event_count_active && (flags & EVLOOP_ONCE))
+				done = 1;
+		} else if (flags & EVLOOP_NONBLOCK)
+			done = 1;
+	}
+
+	event_debug(("%s: asked to terminate loop.", __func__));
+	return (0);
+}
+
+/* Sets up an event for processing once */
+
+struct event_once {
+	struct event ev;
+
+	void (*cb)(int, short, void *);
+	void *arg;
+};
+
+/* One-time callback, it deletes itself */
+
+static void
+event_once_cb(int fd, short events, void *arg)
+{
+	struct event_once *eonce = arg;
+
+	(*eonce->cb)(fd, events, eonce->arg);
+	free(eonce);
+}
+
+/* not threadsafe, event scheduled once. */
+int
+event_once(int fd, short events,
+    void (*callback)(int, short, void *), void *arg, const struct timeval *tv)
+{
+	return event_base_once(current_base, fd, events, callback, arg, tv);
+}
+
+/* Schedules an event once */
+int
+event_base_once(struct event_base *base, int fd, short events,
+    void (*callback)(int, short, void *), void *arg, const struct timeval *tv)
+{
+	struct event_once *eonce;
+	struct timeval etv;
+	int res;
+
+	/* We cannot support signals that just fire once */
+	if (events & EV_SIGNAL)
+		return (-1);
+
+	if ((eonce = calloc(1, sizeof(struct event_once))) == NULL)
+		return (-1);
+
+	eonce->cb = callback;
+	eonce->arg = arg;
+
+	if (events == EV_TIMEOUT) {
+		if (tv == NULL) {
+			evutil_timerclear(&etv);
+			tv = &etv;
+		}
+
+		evtimer_set(&eonce->ev, event_once_cb, eonce);
+	} else if (events & (EV_READ|EV_WRITE)) {
+		events &= EV_READ|EV_WRITE;
+
+		event_set(&eonce->ev, fd, events, event_once_cb, eonce);
+	} else {
+		/* Bad event combination */
+		free(eonce);
+		return (-1);
+	}
+
+	res = event_base_set(base, &eonce->ev);
+	if (res == 0)
+		res = event_add(&eonce->ev, tv);
+	if (res != 0) {
+		free(eonce);
+		return (res);
+	}
+
+	return (0);
+}
+
+void
+event_set(struct event *ev, int fd, short events,
+	  void (*callback)(int, short, void *), void *arg)
+{
+	/* Take the current base - caller needs to set the real base later */
+	ev->ev_base = current_base;
+
+	ev->ev_callback = callback;
+	ev->ev_arg = arg;
+	ev->ev_fd = fd;
+	ev->ev_events = events;
+	ev->ev_res = 0;
+	ev->ev_flags = EVLIST_INIT;
+	ev->ev_ncalls = 0;
+	ev->ev_pncalls = NULL;
+
+	min_heap_elem_init(ev);
+
+	/* by default, we put new events into the middle priority */
+	if(current_base)
+		ev->ev_pri = current_base->nactivequeues/2;
+}
+
+int
+event_base_set(struct event_base *base, struct event *ev)
+{
+	/* Only innocent events may be assigned to a different base */
+	if (ev->ev_flags != EVLIST_INIT)
+		return (-1);
+
+	ev->ev_base = base;
+	ev->ev_pri = base->nactivequeues/2;
+
+	return (0);
+}
+
+/*
+ * Set's the priority of an event - if an event is already scheduled
+ * changing the priority is going to fail.
+ */
+
+int
+event_priority_set(struct event *ev, int pri)
+{
+	if (ev->ev_flags & EVLIST_ACTIVE)
+		return (-1);
+	if (pri < 0 || pri >= ev->ev_base->nactivequeues)
+		return (-1);
+
+	ev->ev_pri = pri;
+
+	return (0);
+}
+
+/*
+ * Checks if a specific event is pending or scheduled.
+ */
+
+int
+event_pending(struct event *ev, short event, struct timeval *tv)
+{
+	struct timeval	now, res;
+	int flags = 0;
+
+	if (ev->ev_flags & EVLIST_INSERTED)
+		flags |= (ev->ev_events & (EV_READ|EV_WRITE|EV_SIGNAL));
+	if (ev->ev_flags & EVLIST_ACTIVE)
+		flags |= ev->ev_res;
+	if (ev->ev_flags & EVLIST_TIMEOUT)
+		flags |= EV_TIMEOUT;
+
+	event &= (EV_TIMEOUT|EV_READ|EV_WRITE|EV_SIGNAL);
+
+	/* See if there is a timeout that we should report */
+	if (tv != NULL && (flags & event & EV_TIMEOUT)) {
+		gettime(ev->ev_base, &now);
+		evutil_timersub(&ev->ev_timeout, &now, &res);
+		/* correctly remap to real time */
+		evutil_gettimeofday(&now, NULL);
+		evutil_timeradd(&now, &res, tv);
+	}
+
+	return (flags & event);
+}
+
+int
+event_add(struct event *ev, const struct timeval *tv)
+{
+	struct event_base *base = ev->ev_base;
+	const struct eventop *evsel = base->evsel;
+	void *evbase = base->evbase;
+	int res = 0;
+
+	event_debug((
+		 "event_add: event: %p, %s%s%scall %p",
+		 ev,
+		 ev->ev_events & EV_READ ? "EV_READ " : " ",
+		 ev->ev_events & EV_WRITE ? "EV_WRITE " : " ",
+		 tv ? "EV_TIMEOUT " : " ",
+		 ev->ev_callback));
+
+	assert(!(ev->ev_flags & ~EVLIST_ALL));
+
+	/*
+	 * prepare for timeout insertion further below, if we get a
+	 * failure on any step, we should not change any state.
+	 */
+	if (tv != NULL && !(ev->ev_flags & EVLIST_TIMEOUT)) {
+		if (min_heap_reserve(&base->timeheap,
+			1 + min_heap_size(&base->timeheap)) == -1)
+			return (-1);  /* ENOMEM == errno */
+	}
+
+	if ((ev->ev_events & (EV_READ|EV_WRITE|EV_SIGNAL)) &&
+	    !(ev->ev_flags & (EVLIST_INSERTED|EVLIST_ACTIVE))) {
+		res = evsel->add(evbase, ev);
+		if (res != -1)
+			event_queue_insert(base, ev, EVLIST_INSERTED);
+	}
+
+	/* 
+	 * we should change the timout state only if the previous event
+	 * addition succeeded.
+	 */
+	if (res != -1 && tv != NULL) {
+		struct timeval now;
+
+		/* 
+		 * we already reserved memory above for the case where we
+		 * are not replacing an exisiting timeout.
+		 */
+		if (ev->ev_flags & EVLIST_TIMEOUT)
+			event_queue_remove(base, ev, EVLIST_TIMEOUT);
+
+		/* Check if it is active due to a timeout.  Rescheduling
+		 * this timeout before the callback can be executed
+		 * removes it from the active list. */
+		if ((ev->ev_flags & EVLIST_ACTIVE) &&
+		    (ev->ev_res & EV_TIMEOUT)) {
+			/* See if we are just active executing this
+			 * event in a loop
+			 */
+			if (ev->ev_ncalls && ev->ev_pncalls) {
+				/* Abort loop */
+				*ev->ev_pncalls = 0;
+			}
+			
+			event_queue_remove(base, ev, EVLIST_ACTIVE);
+		}
+
+		gettime(base, &now);
+		evutil_timeradd(&now, tv, &ev->ev_timeout);
+
+		event_debug((
+			 "event_add: timeout in %ld seconds, call %p",
+			 tv->tv_sec, ev->ev_callback));
+
+		event_queue_insert(base, ev, EVLIST_TIMEOUT);
+	}
+
+	return (0);
+}
+
+int
+event_del(struct event *ev)
+{
+	struct event_base *base;
+	const struct eventop *evsel;
+	void *evbase;
+
+	event_debug(("event_del: %p, callback %p",
+		 ev, ev->ev_callback));
+
+	/* An event without a base has not been added */
+	if (ev->ev_base == NULL)
+		return (-1);
+
+	base = ev->ev_base;
+	evsel = base->evsel;
+	evbase = base->evbase;
+
+	assert(!(ev->ev_flags & ~EVLIST_ALL));
+
+	/* See if we are just active executing this event in a loop */
+	if (ev->ev_ncalls && ev->ev_pncalls) {
+		/* Abort loop */
+		*ev->ev_pncalls = 0;
+	}
+
+	if (ev->ev_flags & EVLIST_TIMEOUT)
+		event_queue_remove(base, ev, EVLIST_TIMEOUT);
+
+	if (ev->ev_flags & EVLIST_ACTIVE)
+		event_queue_remove(base, ev, EVLIST_ACTIVE);
+
+	if (ev->ev_flags & EVLIST_INSERTED) {
+		event_queue_remove(base, ev, EVLIST_INSERTED);
+		return (evsel->del(evbase, ev));
+	}
+
+	return (0);
+}
+
+void
+event_active(struct event *ev, int res, short ncalls)
+{
+	/* We get different kinds of events, add them together */
+	if (ev->ev_flags & EVLIST_ACTIVE) {
+		ev->ev_res |= res;
+		return;
+	}
+
+	ev->ev_res = res;
+	ev->ev_ncalls = ncalls;
+	ev->ev_pncalls = NULL;
+	event_queue_insert(ev->ev_base, ev, EVLIST_ACTIVE);
+}
+
+static int
+timeout_next(struct event_base *base, struct timeval **tv_p)
+{
+	struct timeval now;
+	struct event *ev;
+	struct timeval *tv = *tv_p;
+
+	if ((ev = min_heap_top(&base->timeheap)) == NULL) {
+		/* if no time-based events are active wait for I/O */
+		*tv_p = NULL;
+		return (0);
+	}
+
+	if (gettime(base, &now) == -1)
+		return (-1);
+
+	if (evutil_timercmp(&ev->ev_timeout, &now, <=)) {
+		evutil_timerclear(tv);
+		return (0);
+	}
+
+	evutil_timersub(&ev->ev_timeout, &now, tv);
+
+	assert(tv->tv_sec >= 0);
+	assert(tv->tv_usec >= 0);
+
+	event_debug(("timeout_next: in %ld seconds", tv->tv_sec));
+	return (0);
+}
+
+/*
+ * Determines if the time is running backwards by comparing the current
+ * time against the last time we checked.  Not needed when using clock
+ * monotonic.
+ */
+
+static void
+timeout_correct(struct event_base *base, struct timeval *tv)
+{
+	struct event **pev;
+	unsigned int size;
+	struct timeval off;
+
+	if (use_monotonic)
+		return;
+
+	/* Check if time is running backwards */
+	gettime(base, tv);
+	if (evutil_timercmp(tv, &base->event_tv, >=)) {
+		base->event_tv = *tv;
+		return;
+	}
+
+	event_debug(("%s: time is running backwards, corrected",
+		    __func__));
+	evutil_timersub(&base->event_tv, tv, &off);
+
+	/*
+	 * We can modify the key element of the node without destroying
+	 * the key, beause we apply it to all in the right order.
+	 */
+	pev = base->timeheap.p;
+	size = base->timeheap.n;
+	for (; size-- > 0; ++pev) {
+		struct timeval *ev_tv = &(**pev).ev_timeout;
+		evutil_timersub(ev_tv, &off, ev_tv);
+	}
+}
+
+void
+timeout_process(struct event_base *base)
+{
+	struct timeval now;
+	struct event *ev;
+
+	if (min_heap_empty(&base->timeheap))
+		return;
+
+	gettime(base, &now);
+
+	while ((ev = min_heap_top(&base->timeheap))) {
+		if (evutil_timercmp(&ev->ev_timeout, &now, >))
+			break;
+
+		/* delete this event from the I/O queues */
+		event_del(ev);
+
+		event_debug(("timeout_process: call %p",
+			 ev->ev_callback));
+		event_active(ev, EV_TIMEOUT, 1);
+	}
+}
+
+void
+event_queue_remove(struct event_base *base, struct event *ev, int queue)
+{
+	if (!(ev->ev_flags & queue))
+		event_errx(1, "%s: %p(fd %d) not on queue %x", __func__,
+			   ev, ev->ev_fd, queue);
+
+	if (~ev->ev_flags & EVLIST_INTERNAL)
+		base->event_count--;
+
+	ev->ev_flags &= ~queue;
+	switch (queue) {
+	case EVLIST_INSERTED:
+		TAILQ_REMOVE(&base->eventqueue, ev, ev_next);
+		break;
+	case EVLIST_ACTIVE:
+		base->event_count_active--;
+		TAILQ_REMOVE(base->activequeues[ev->ev_pri],
+		    ev, ev_active_next);
+		break;
+	case EVLIST_TIMEOUT:
+		min_heap_erase(&base->timeheap, ev);
+		break;
+	default:
+		event_errx(1, "%s: unknown queue %x", __func__, queue);
+	}
+}
+
+void
+event_queue_insert(struct event_base *base, struct event *ev, int queue)
+{
+	if (ev->ev_flags & queue) {
+		/* Double insertion is possible for active events */
+		if (queue & EVLIST_ACTIVE)
+			return;
+
+		event_errx(1, "%s: %p(fd %d) already on queue %x", __func__,
+			   ev, ev->ev_fd, queue);
+	}
+
+	if (~ev->ev_flags & EVLIST_INTERNAL)
+		base->event_count++;
+
+	ev->ev_flags |= queue;
+	switch (queue) {
+	case EVLIST_INSERTED:
+		TAILQ_INSERT_TAIL(&base->eventqueue, ev, ev_next);
+		break;
+	case EVLIST_ACTIVE:
+		base->event_count_active++;
+		TAILQ_INSERT_TAIL(base->activequeues[ev->ev_pri],
+		    ev,ev_active_next);
+		break;
+	case EVLIST_TIMEOUT: {
+		min_heap_push(&base->timeheap, ev);
+		break;
+	}
+	default:
+		event_errx(1, "%s: unknown queue %x", __func__, queue);
+	}
+}
+
+/* Functions for debugging */
+
+const char *
+event_get_version(void)
+{
+	return (VERSION);
+}
+
+/* 
+ * No thread-safe interface needed - the information should be the same
+ * for all threads.
+ */
+
+const char *
+event_get_method(void)
+{
+	return (current_base->evsel->name);
+}