/*      $NetBSD: bench.c,v 1.1.1.3 2021/04/07 02:43:15 christos Exp $   */
/*
* Copyright 2003-2007 Niels Provos <[email protected]>
* Copyright 2007-2012 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.
* 4. 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.
*
*
* Mon 03/10/2003 - Modified by Davide Libenzi <[email protected]>
*
*     Added chain event propagation to improve the sensitivity of
*     the measure respect to the event loop efficency.
*
*
*/

#include "event2/event-config.h"
#include <sys/cdefs.h>
__RCSID("$NetBSD: bench.c,v 1.1.1.3 2021/04/07 02:43:15 christos Exp $");
#include "../util-internal.h"

#include <sys/types.h>
#include <sys/stat.h>
#ifdef EVENT__HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#ifdef _WIN32
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#else
#include <sys/socket.h>
#include <signal.h>
#include <sys/resource.h>
#endif
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#ifdef EVENT__HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <errno.h>

#ifdef _WIN32
#include <getopt.h>
#endif

#include <event.h>
#include <evutil.h>

static ev_ssize_t count, fired;
static int writes, failures;
static evutil_socket_t *pipes;
static int num_pipes, num_active, num_writes;
static struct event *events;
static struct event_base *base;


static void
read_cb(evutil_socket_t fd, short which, void *arg)
{
       ev_intptr_t idx = (ev_intptr_t) arg, widx = idx + 1;
       unsigned char ch;
       ev_ssize_t n;

       n = recv(fd, (char*)&ch, sizeof(ch), 0);
       if (n >= 0)
               count += n;
       else
               failures++;
       if (writes) {
               if (widx >= num_pipes)
                       widx -= num_pipes;
               n = send(pipes[2 * widx + 1], "e", 1, 0);
               if (n != 1)
                       failures++;
               writes--;
               fired++;
       }
}

static struct timeval *
run_once(void)
{
       evutil_socket_t *cp, space;
       long i;
       static struct timeval ts, te;

       for (cp = pipes, i = 0; i < num_pipes; i++, cp += 2) {
               if (event_initialized(&events[i]))
                       event_del(&events[i]);
               event_assign(&events[i], base, cp[0], EV_READ | EV_PERSIST, read_cb, (void *)(ev_intptr_t) i);
               event_add(&events[i], NULL);
       }

       event_base_loop(base, EVLOOP_ONCE | EVLOOP_NONBLOCK);

       fired = 0;
       space = num_pipes / num_active;
       space = space * 2;
       for (i = 0; i < num_active; i++, fired++)
               (void) send(pipes[i * space + 1], "e", 1, 0);

       count = 0;
       writes = num_writes;
       {
               int xcount = 0;
               evutil_gettimeofday(&ts, NULL);
               do {
                       event_base_loop(base, EVLOOP_ONCE | EVLOOP_NONBLOCK);
                       xcount++;
               } while (count != fired);
               evutil_gettimeofday(&te, NULL);

               if (xcount != count)
                       fprintf(stderr, "Xcount: %d, Rcount: " EV_SSIZE_FMT "\n",
                               xcount, count);
       }

       evutil_timersub(&te, &ts, &te);

       return (&te);
}

int
main(int argc, char **argv)
{
#ifdef EVENT__HAVE_SETRLIMIT
       struct rlimit rl;
#endif
       int i, c;
       struct timeval *tv;
       evutil_socket_t *cp;
       const char **methods;
       const char *method = NULL;
       struct event_config *cfg = NULL;

#ifdef _WIN32
       WSADATA WSAData;
       WSAStartup(0x101, &WSAData);
#endif
       num_pipes = 100;
       num_active = 1;
       num_writes = num_pipes;
       while ((c = getopt(argc, argv, "n:a:w:m:l")) != -1) {
               switch (c) {
               case 'n':
                       num_pipes = atoi(optarg);
                       break;
               case 'a':
                       num_active = atoi(optarg);
                       break;
               case 'w':
                       num_writes = atoi(optarg);
                       break;
               case 'm':
                       method = optarg;
                       break;
               case 'l':
                       methods = event_get_supported_methods();
                       fprintf(stdout, "Using Libevent %s. Available methods are:\n",
                               event_get_version());
                       for (i = 0; methods[i] != NULL; ++i)
                               printf("    %s\n", methods[i]);
                       exit(0);
               default:
                       fprintf(stderr, "Illegal argument \"%c\"\n", c);
                       exit(1);
               }
       }

#ifdef EVENT__HAVE_SETRLIMIT
       rl.rlim_cur = rl.rlim_max = num_pipes * 2 + 50;
       if (setrlimit(RLIMIT_NOFILE, &rl) == -1) {
               perror("setrlimit");
               exit(1);
       }
#endif

       events = calloc(num_pipes, sizeof(struct event));
       pipes = calloc(num_pipes * 2, sizeof(evutil_socket_t));
       if (events == NULL || pipes == NULL) {
               perror("malloc");
               exit(1);
       }

       if (method != NULL) {
               cfg = event_config_new();
               methods = event_get_supported_methods();
               for (i = 0; methods[i] != NULL; ++i)
                       if (strcmp(methods[i], method))
                               event_config_avoid_method(cfg, methods[i]);
               base = event_base_new_with_config(cfg);
               event_config_free(cfg);
       } else
               base = event_base_new();

       for (cp = pipes, i = 0; i < num_pipes; i++, cp += 2) {
#ifdef USE_PIPES
               if (pipe(cp) == -1) {
#else
               if (evutil_socketpair(AF_UNIX, SOCK_STREAM, 0, cp) == -1) {
#endif
                       perror("pipe");
                       exit(1);
               }
       }

       for (i = 0; i < 25; i++) {
               tv = run_once();
               if (tv == NULL)
                       exit(1);
               fprintf(stdout, "%ld\n",
                       tv->tv_sec * 1000000L + tv->tv_usec);
       }

       exit(0);
}