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/*
* Copyright (c) 2009-2012 Niels Provos and Nick Mathewson
*
* 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.
*/
#include "../util-internal.h"
#include "event2/event-config.h"
#ifdef _WIN32
#include <winsock2.h>
#endif
#include <sys/types.h>
#include <sys/stat.h>
#ifdef EVENT__HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#ifndef _WIN32
#include <sys/time.h>
#include <unistd.h>
#endif
#include <errno.h>
#include "event2/event.h"
#include "event2/util.h"
#include "regress.h"
static int was_et = 0;
static int base_supports_et(struct event_base *base)
{
return
(!strcmp(event_base_get_method(base), "epoll") ||
!strcmp(event_base_get_method(base), "epoll (with changelist)") ||
!strcmp(event_base_get_method(base), "kqueue"));
}
static void
read_cb(evutil_socket_t fd, short event, void *arg)
{
char buf;
int len;
len = recv(fd, &buf, sizeof(buf), 0);
called++;
if (event & EV_ET)
was_et = 1;
if (!len)
event_del(arg);
}
static void
test_edgetriggered(void *data_)
{
struct basic_test_data *data = data_;
struct event_base *base = data->base;
evutil_socket_t *pair = data->pair;
struct event *ev = NULL;
const char *test = "test string";
int supports_et;
/* On Linux 3.2.1 (at least, as patched by Fedora and tested by Nick),
* doing a "recv" on an AF_UNIX socket resets the readability of the
* socket, even though there is no state change, so we don't actually
* get edge-triggered behavior. Yuck! Linux 3.1.9 didn't have this
* problem.
*/
called = was_et = 0;
tt_int_op(send(pair[0], test, (int)strlen(test)+1, 0), >, 0);
tt_int_op(shutdown(pair[0], EVUTIL_SHUT_WR), ==, 0);
supports_et = base_supports_et(base);
TT_BLATHER(("Checking for edge-triggered events with %s, which should %s"
"support edge-triggering", event_base_get_method(base),
supports_et?"":"not "));
/* Initialize one event */
ev = event_new(base, pair[1], EV_READ|EV_ET|EV_PERSIST, read_cb, &ev);
tt_assert(ev != NULL);
tt_int_op(event_add(ev, NULL), ==, 0);
/* We're going to call the dispatch function twice. The first invocation
* will read a single byte from pair[1] in either case. If we're edge
* triggered, we'll only see the event once (since we only see transitions
* from no data to data), so the second invocation of event_base_loop will
* do nothing. If we're level triggered, the second invocation of
* event_base_loop will also activate the event (because there's still
* data to read). */
tt_int_op(event_base_loop(base,EVLOOP_NONBLOCK|EVLOOP_ONCE), ==, 0);
tt_int_op(event_base_loop(base,EVLOOP_NONBLOCK|EVLOOP_ONCE), ==, 0);
if (supports_et) {
tt_int_op(called, ==, 1);
tt_assert(was_et);
} else {
tt_int_op(called, ==, 2);
tt_assert(!was_et);
}
end:
if (ev) {
event_del(ev);
event_free(ev);
}
}
static void
test_edgetriggered_mix_error(void *data_)
{
struct basic_test_data *data = data_;
struct event_base *base = NULL;
struct event *ev_et=NULL, *ev_lt=NULL;
#ifdef EVENT__DISABLE_DEBUG_MODE
if (1)
tt_skip();
#endif
if (!libevent_tests_running_in_debug_mode)
event_enable_debug_mode();
base = event_base_new();
/* try mixing edge-triggered and level-triggered to make sure it fails*/
ev_et = event_new(base, data->pair[0], EV_READ|EV_ET, read_cb, ev_et);
tt_assert(ev_et);
ev_lt = event_new(base, data->pair[0], EV_READ, read_cb, ev_lt);
tt_assert(ev_lt);
/* Add edge-triggered, then level-triggered. Get an error. */
tt_int_op(0, ==, event_add(ev_et, NULL));
tt_int_op(-1, ==, event_add(ev_lt, NULL));
tt_int_op(EV_READ, ==, event_pending(ev_et, EV_READ, NULL));
tt_int_op(0, ==, event_pending(ev_lt, EV_READ, NULL));
tt_int_op(0, ==, event_del(ev_et));
/* Add level-triggered, then edge-triggered. Get an error. */
tt_int_op(0, ==, event_add(ev_lt, NULL));
tt_int_op(-1, ==, event_add(ev_et, NULL));
tt_int_op(EV_READ, ==, event_pending(ev_lt, EV_READ, NULL));
tt_int_op(0, ==, event_pending(ev_et, EV_READ, NULL));
end:
if (ev_et)
event_free(ev_et);
if (ev_lt)
event_free(ev_lt);
if (base)
event_base_free(base);
}
static int read_notification_count;
static int last_read_notification_was_et;
static void
read_notification_cb(evutil_socket_t fd, short event, void *arg)
{
read_notification_count++;
last_read_notification_was_et = (event & EV_ET);
}
static int write_notification_count;
static int last_write_notification_was_et;
static void
write_notification_cb(evutil_socket_t fd, short event, void *arg)
{
write_notification_count++;
last_write_notification_was_et = (event & EV_ET);
}
/* After two or more events have been registered for the same
* file descriptor using EV_ET, if one of the events is
* deleted, then the epoll_ctl() call issued by libevent drops
* the EPOLLET flag resulting in level triggered
* notifications.
*/
static void
test_edge_triggered_multiple_events(void *data_)
{
struct basic_test_data *data = data_;
struct event *read_ev = NULL;
struct event *write_ev = NULL;
const char c = 'A';
struct event_base *base = data->base;
evutil_socket_t *pair = data->pair;
if (!base_supports_et(base)) {
tt_skip();
return;
}
read_notification_count = 0;
last_read_notification_was_et = 0;
write_notification_count = 0;
last_write_notification_was_et = 0;
/* Make pair[1] readable */
tt_int_op(send(pair[0], &c, 1, 0), >, 0);
read_ev = event_new(base, pair[1], EV_READ|EV_ET|EV_PERSIST,
read_notification_cb, NULL);
write_ev = event_new(base, pair[1], EV_WRITE|EV_ET|EV_PERSIST,
write_notification_cb, NULL);
event_add(read_ev, NULL);
event_add(write_ev, NULL);
event_base_loop(base, EVLOOP_NONBLOCK|EVLOOP_ONCE);
event_base_loop(base, EVLOOP_NONBLOCK|EVLOOP_ONCE);
tt_assert(last_read_notification_was_et);
tt_int_op(read_notification_count, ==, 1);
tt_assert(last_write_notification_was_et);
tt_int_op(write_notification_count, ==, 1);
event_del(read_ev);
/* trigger acitivity second time for the backend that can have multiple
* events for one fd (like kqueue) */
close(pair[0]);
pair[0] = -1;
/* Verify that we are still edge-triggered for write notifications */
event_base_loop(base, EVLOOP_NONBLOCK|EVLOOP_ONCE);
event_base_loop(base, EVLOOP_NONBLOCK|EVLOOP_ONCE);
tt_assert(last_write_notification_was_et);
tt_int_op(write_notification_count, ==, 2);
end:
if (read_ev)
event_free(read_ev);
if (write_ev)
event_free(write_ev);
}
struct testcase_t edgetriggered_testcases[] = {
{ "et", test_edgetriggered,
TT_FORK|TT_NEED_BASE|TT_NEED_SOCKETPAIR, &basic_setup, NULL },
{ "et_mix_error", test_edgetriggered_mix_error,
TT_FORK|TT_NEED_SOCKETPAIR|TT_NO_LOGS, &basic_setup, NULL },
{ "et_multiple_events", test_edge_triggered_multiple_events,
TT_FORK|TT_NEED_BASE|TT_NEED_SOCKETPAIR, &basic_setup, NULL },
END_OF_TESTCASES
};