1 /*	$NetBSD: test-ratelim.c,v 1.1.1.3 2021/04/07 02:43:15 christos Exp $	*/
2 /*
3  * Copyright (c) 2009-2012 Niels Provos and Nick Mathewson
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 #include "../util-internal.h"
28 
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <assert.h>
33 #include <math.h>
34 
35 #ifdef _WIN32
36 #include <winsock2.h>
37 #include <ws2tcpip.h>
38 #else
39 #include <sys/socket.h>
40 #include <netinet/in.h>
41 # ifdef _XOPEN_SOURCE_EXTENDED
42 #  include <arpa/inet.h>
43 # endif
44 #endif
45 #include <signal.h>
46 
47 #include "event2/bufferevent.h"
48 #include "event2/buffer.h"
49 #include "event2/event.h"
50 #include "event2/util.h"
51 #include "event2/listener.h"
52 #include "event2/thread.h"
53 
54 #ifndef MIN
55 #define MIN(a,b) (((a)<(b))?(a):(b))
56 #endif
57 
58 static struct evutil_weakrand_state weakrand_state;
59 
60 static int cfg_verbose = 0;
61 static int cfg_help = 0;
62 
63 static int cfg_n_connections = 30;
64 static int cfg_duration = 5;
65 static int cfg_connlimit = 0;
66 static int cfg_grouplimit = 0;
67 static int cfg_tick_msec = 1000;
68 static int cfg_min_share = -1;
69 static int cfg_group_drain = 0;
70 
71 static int cfg_connlimit_tolerance = -1;
72 static int cfg_grouplimit_tolerance = -1;
73 static int cfg_stddev_tolerance = -1;
74 
75 #ifdef _WIN32
76 static int cfg_enable_iocp = 0;
77 #endif
78 
79 static struct timeval cfg_tick = { 0, 500*1000 };
80 
81 static struct ev_token_bucket_cfg *conn_bucket_cfg = NULL;
82 static struct ev_token_bucket_cfg *group_bucket_cfg = NULL;
83 struct bufferevent_rate_limit_group *ratelim_group = NULL;
84 static double seconds_per_tick = 0.0;
85 
86 struct client_state {
87 	size_t queued;
88 	ev_uint64_t received;
89 
90 };
91 static const struct timeval *ms100_common=NULL;
92 
93 /* Timers bias for slow CPUs, affects:
94  * - cfg_connlimit_tolerance  (--check-connlimit)
95  * - cfg_grouplimit_tolerance (--check-grouplimit)
96  * - cfg_stddev_tolerance     (--check-stddev)
97  */
98 static int timer_bias_events;
99 static struct timeval timer_bias_start;
100 double timer_bias_spend;
101 /* Real cost is less (approximately ~5 usec),
102  * this macros adjusted to make the bias less */
103 #define TIMER_MAX_COST_USEC 10
104 
105 /* info from check_bucket_levels_cb */
106 static int total_n_bev_checks = 0;
107 static ev_int64_t total_rbucket_level=0;
108 static ev_int64_t total_wbucket_level=0;
109 static ev_int64_t total_max_to_read=0;
110 static ev_int64_t total_max_to_write=0;
111 static ev_int64_t max_bucket_level=EV_INT64_MIN;
112 static ev_int64_t min_bucket_level=EV_INT64_MAX;
113 
114 /* from check_group_bucket_levels_cb */
115 static int total_n_group_bev_checks = 0;
116 static ev_int64_t total_group_rbucket_level = 0;
117 static ev_int64_t total_group_wbucket_level = 0;
118 
119 static int n_echo_conns_open = 0;
120 
121 /* Info on the open connections */
122 struct bufferevent **bevs;
123 struct client_state *states;
124 struct bufferevent_rate_limit_group *group = NULL;
125 
126 static void check_bucket_levels_cb(evutil_socket_t fd, short events, void *arg);
127 
128 static void
loud_writecb(struct bufferevent * bev,void * ctx)129 loud_writecb(struct bufferevent *bev, void *ctx)
130 {
131 	struct client_state *cs = ctx;
132 	struct evbuffer *output = bufferevent_get_output(bev);
133 	char buf[1024];
134 	int r = evutil_weakrand_(&weakrand_state);
135 	memset(buf, r, sizeof(buf));
136 	while (evbuffer_get_length(output) < 8192) {
137 		evbuffer_add(output, buf, sizeof(buf));
138 		cs->queued += sizeof(buf);
139 	}
140 }
141 
142 static void
discard_readcb(struct bufferevent * bev,void * ctx)143 discard_readcb(struct bufferevent *bev, void *ctx)
144 {
145 	struct client_state *cs = ctx;
146 	struct evbuffer *input = bufferevent_get_input(bev);
147 	size_t len = evbuffer_get_length(input);
148 	evbuffer_drain(input, len);
149 	cs->received += len;
150 }
151 
152 static void
write_on_connectedcb(struct bufferevent * bev,short what,void * ctx)153 write_on_connectedcb(struct bufferevent *bev, short what, void *ctx)
154 {
155 	if (what & BEV_EVENT_CONNECTED) {
156 		loud_writecb(bev, ctx);
157 		/* XXXX this shouldn't be needed. */
158 		bufferevent_enable(bev, EV_READ|EV_WRITE);
159 	}
160 }
161 
162 static void
echo_readcb(struct bufferevent * bev,void * ctx)163 echo_readcb(struct bufferevent *bev, void *ctx)
164 {
165 	struct evbuffer *input = bufferevent_get_input(bev);
166 	struct evbuffer *output = bufferevent_get_output(bev);
167 
168 	evbuffer_add_buffer(output, input);
169 	if (evbuffer_get_length(output) > 1024000)
170 		bufferevent_disable(bev, EV_READ);
171 }
172 
173 static void
echo_writecb(struct bufferevent * bev,void * ctx)174 echo_writecb(struct bufferevent *bev, void *ctx)
175 {
176 	struct evbuffer *output = bufferevent_get_output(bev);
177 	if (evbuffer_get_length(output) < 512000)
178 		bufferevent_enable(bev, EV_READ);
179 }
180 
181 static void
echo_eventcb(struct bufferevent * bev,short what,void * ctx)182 echo_eventcb(struct bufferevent *bev, short what, void *ctx)
183 {
184 	if (what & (BEV_EVENT_EOF|BEV_EVENT_ERROR)) {
185 		--n_echo_conns_open;
186 		bufferevent_free(bev);
187 	}
188 }
189 
190 static void
echo_listenercb(struct evconnlistener * listener,evutil_socket_t newsock,struct sockaddr * sourceaddr,int socklen,void * ctx)191 echo_listenercb(struct evconnlistener *listener, evutil_socket_t newsock,
192     struct sockaddr *sourceaddr, int socklen, void *ctx)
193 {
194 	struct event_base *base = ctx;
195 	int flags = BEV_OPT_CLOSE_ON_FREE|BEV_OPT_THREADSAFE;
196 	struct bufferevent *bev;
197 
198 	bev = bufferevent_socket_new(base, newsock, flags);
199 	bufferevent_setcb(bev, echo_readcb, echo_writecb, echo_eventcb, NULL);
200 	if (conn_bucket_cfg) {
201 		struct event *check_event =
202 		    event_new(base, -1, EV_PERSIST, check_bucket_levels_cb, bev);
203 		bufferevent_set_rate_limit(bev, conn_bucket_cfg);
204 
205 		assert(bufferevent_get_token_bucket_cfg(bev) != NULL);
206 		event_add(check_event, ms100_common);
207 	}
208 	if (ratelim_group)
209 		bufferevent_add_to_rate_limit_group(bev, ratelim_group);
210 	++n_echo_conns_open;
211 	bufferevent_enable(bev, EV_READ|EV_WRITE);
212 }
213 
214 /* Called periodically to check up on how full the buckets are */
215 static void
check_bucket_levels_cb(evutil_socket_t fd,short events,void * arg)216 check_bucket_levels_cb(evutil_socket_t fd, short events, void *arg)
217 {
218 	struct bufferevent *bev = arg;
219 
220 	ev_ssize_t r = bufferevent_get_read_limit(bev);
221 	ev_ssize_t w = bufferevent_get_write_limit(bev);
222 	ev_ssize_t rm = bufferevent_get_max_to_read(bev);
223 	ev_ssize_t wm = bufferevent_get_max_to_write(bev);
224 	/* XXXX check that no value is above the cofigured burst
225 	 * limit */
226 	total_rbucket_level += r;
227 	total_wbucket_level += w;
228 	total_max_to_read += rm;
229 	total_max_to_write += wm;
230 #define B(x) \
231 	if ((x) > max_bucket_level)		\
232 		max_bucket_level = (x);		\
233 	if ((x) < min_bucket_level)		\
234 		min_bucket_level = (x)
235 	B(r);
236 	B(w);
237 #undef B
238 
239 	total_n_bev_checks++;
240 	if (total_n_bev_checks >= .8 * ((double)cfg_duration / cfg_tick_msec) * cfg_n_connections) {
241 		event_free(event_base_get_running_event(bufferevent_get_base(bev)));
242 	}
243 }
244 
245 static void
check_group_bucket_levels_cb(evutil_socket_t fd,short events,void * arg)246 check_group_bucket_levels_cb(evutil_socket_t fd, short events, void *arg)
247 {
248 	if (ratelim_group) {
249 		ev_ssize_t r = bufferevent_rate_limit_group_get_read_limit(ratelim_group);
250 		ev_ssize_t w = bufferevent_rate_limit_group_get_write_limit(ratelim_group);
251 		total_group_rbucket_level += r;
252 		total_group_wbucket_level += w;
253 	}
254 	++total_n_group_bev_checks;
255 }
256 
257 static void
group_drain_cb(evutil_socket_t fd,short events,void * arg)258 group_drain_cb(evutil_socket_t fd, short events, void *arg)
259 {
260 	bufferevent_rate_limit_group_decrement_read(ratelim_group, cfg_group_drain);
261 	bufferevent_rate_limit_group_decrement_write(ratelim_group, cfg_group_drain);
262 }
263 
264 static void
timer_bias_cb(evutil_socket_t fd,short events,void * arg)265 timer_bias_cb(evutil_socket_t fd, short events, void *arg)
266 {
267 	struct event *event = arg;
268 	struct timeval end;
269 	struct timeval diff;
270 
271 	/** XXX: use rdtsc? (portability issues?) */
272 	evutil_gettimeofday(&end, NULL);
273 	evutil_timersub(&end, &timer_bias_start, &diff);
274 	timer_bias_spend += diff.tv_sec + diff.tv_usec * 1e6;
275 	timer_bias_start = end;
276 
277 	if (++timer_bias_events == 100)
278 		event_del(event);
279 }
280 static double
timer_bias_calculate(void)281 timer_bias_calculate(void)
282 {
283 	struct event_config *cfg = NULL;
284 	struct event_base *base = NULL;
285 	struct event *timer = NULL;
286 	struct timeval tv = { 0, 1 };
287 	int done = 0;
288 
289 	cfg = event_config_new();
290 	if (!cfg)
291 		goto err;
292 	if (event_config_set_flag(cfg, EVENT_BASE_FLAG_PRECISE_TIMER))
293 		goto err;
294 	base = event_base_new_with_config(cfg);
295 	if (!base)
296 		goto err;
297 
298 	timer = event_new(base, -1, EV_PERSIST, timer_bias_cb, event_self_cbarg());
299 	if (!timer || event_add(timer, &tv)) {
300 		goto err;
301 	}
302 
303 	evutil_gettimeofday(&timer_bias_start, NULL);
304 	event_base_dispatch(base);
305 	done = 1;
306 
307 err:
308 	if (cfg)
309 		event_config_free(cfg);
310 	if (timer)
311 		event_free(timer);
312 	if (base)
313 		event_base_free(base);
314 
315 	if (done)
316 		return MIN(timer_bias_spend / 1e6 / timer_bias_events / TIMER_MAX_COST_USEC, 5);
317 
318 	fprintf(stderr, "Couldn't create event for CPU cycle counter bias\n");
319 	return -1;
320 }
321 
322 static int
test_ratelimiting(void)323 test_ratelimiting(void)
324 {
325 	struct event_base *base;
326 	struct sockaddr_in sin;
327 	struct evconnlistener *listener;
328 
329 	struct sockaddr_storage ss;
330 	ev_socklen_t slen;
331 
332 	int i;
333 
334 	struct timeval tv;
335 
336 	ev_uint64_t total_received;
337 	double total_sq_persec, total_persec;
338 	double variance;
339 	double expected_total_persec = -1.0, expected_avg_persec = -1.0;
340 	int ok = 1;
341 	struct event_config *base_cfg;
342 	struct event *periodic_level_check;
343 	struct event *group_drain_event=NULL;
344 	double timer_bias;
345 
346 	memset(&sin, 0, sizeof(sin));
347 	sin.sin_family = AF_INET;
348 	sin.sin_addr.s_addr = htonl(0x7f000001); /* 127.0.0.1 */
349 	sin.sin_port = 0; /* unspecified port */
350 
351 	if (0)
352 		event_enable_debug_mode();
353 
354 	timer_bias = timer_bias_calculate();
355 	if (timer_bias > 1) {
356 		fprintf(stderr, "CPU is slow, timers bias is %f\n", timer_bias);
357 		cfg_connlimit_tolerance  *= timer_bias;
358 		cfg_grouplimit_tolerance *= timer_bias;
359 		cfg_stddev_tolerance     *= timer_bias;
360 	} else {
361 		printf("CPU is fast enough, timers bias is %f\n", timer_bias);
362 	}
363 
364 	base_cfg = event_config_new();
365 
366 #ifdef _WIN32
367 	if (cfg_enable_iocp) {
368 #ifdef EVTHREAD_USE_WINDOWS_THREADS_IMPLEMENTED
369 		evthread_use_windows_threads();
370 #endif
371 		event_config_set_flag(base_cfg, EVENT_BASE_FLAG_STARTUP_IOCP);
372 	}
373 #endif
374 
375 	base = event_base_new_with_config(base_cfg);
376 	event_config_free(base_cfg);
377 	if (! base) {
378 		fprintf(stderr, "Couldn't create event_base");
379 		return 1;
380 	}
381 
382 	listener = evconnlistener_new_bind(base, echo_listenercb, base,
383 	    LEV_OPT_CLOSE_ON_FREE|LEV_OPT_REUSEABLE, -1,
384 	    (struct sockaddr *)&sin, sizeof(sin));
385 	if (! listener) {
386 		fprintf(stderr, "Couldn't create listener");
387 		return 1;
388 	}
389 
390 	slen = sizeof(ss);
391 	if (getsockname(evconnlistener_get_fd(listener), (struct sockaddr *)&ss,
392 		&slen) < 0) {
393 		perror("getsockname");
394 		return 1;
395 	}
396 
397 	if (cfg_connlimit > 0) {
398 		conn_bucket_cfg = ev_token_bucket_cfg_new(
399 			cfg_connlimit, cfg_connlimit * 4,
400 			cfg_connlimit, cfg_connlimit * 4,
401 			&cfg_tick);
402 		assert(conn_bucket_cfg);
403 	}
404 
405 	if (cfg_grouplimit > 0) {
406 		group_bucket_cfg = ev_token_bucket_cfg_new(
407 			cfg_grouplimit, cfg_grouplimit * 4,
408 			cfg_grouplimit, cfg_grouplimit * 4,
409 			&cfg_tick);
410 		group = ratelim_group = bufferevent_rate_limit_group_new(
411 			base, group_bucket_cfg);
412 		expected_total_persec = cfg_grouplimit - (cfg_group_drain / seconds_per_tick);
413 		expected_avg_persec = cfg_grouplimit / cfg_n_connections;
414 		if (cfg_connlimit > 0 && expected_avg_persec > cfg_connlimit)
415 			expected_avg_persec = cfg_connlimit;
416 		if (cfg_min_share >= 0)
417 			bufferevent_rate_limit_group_set_min_share(
418 				ratelim_group, cfg_min_share);
419 	}
420 
421 	if (expected_avg_persec < 0 && cfg_connlimit > 0)
422 		expected_avg_persec = cfg_connlimit;
423 
424 	if (expected_avg_persec > 0)
425 		expected_avg_persec /= seconds_per_tick;
426 	if (expected_total_persec > 0)
427 		expected_total_persec /= seconds_per_tick;
428 
429 	bevs = calloc(cfg_n_connections, sizeof(struct bufferevent *));
430 	states = calloc(cfg_n_connections, sizeof(struct client_state));
431 
432 	for (i = 0; i < cfg_n_connections; ++i) {
433 		bevs[i] = bufferevent_socket_new(base, -1,
434 		    BEV_OPT_CLOSE_ON_FREE|BEV_OPT_THREADSAFE);
435 		assert(bevs[i]);
436 		bufferevent_setcb(bevs[i], discard_readcb, loud_writecb,
437 		    write_on_connectedcb, &states[i]);
438 		bufferevent_enable(bevs[i], EV_READ|EV_WRITE);
439 		bufferevent_socket_connect(bevs[i], (struct sockaddr *)&ss,
440 		    slen);
441 	}
442 
443 	tv.tv_sec = cfg_duration - 1;
444 	tv.tv_usec = 995000;
445 
446 	event_base_loopexit(base, &tv);
447 
448 	tv.tv_sec = 0;
449 	tv.tv_usec = 100*1000;
450 	ms100_common = event_base_init_common_timeout(base, &tv);
451 
452 	periodic_level_check = event_new(base, -1, EV_PERSIST, check_group_bucket_levels_cb, NULL);
453 	event_add(periodic_level_check, ms100_common);
454 
455 	if (cfg_group_drain && ratelim_group) {
456 		group_drain_event = event_new(base, -1, EV_PERSIST, group_drain_cb, NULL);
457 		event_add(group_drain_event, &cfg_tick);
458 	}
459 
460 	event_base_dispatch(base);
461 
462 	ratelim_group = NULL; /* So no more responders get added */
463 	event_free(periodic_level_check);
464 	if (group_drain_event)
465 		event_free(group_drain_event);
466 
467 	for (i = 0; i < cfg_n_connections; ++i) {
468 		bufferevent_free(bevs[i]);
469 	}
470 	evconnlistener_free(listener);
471 
472 	/* Make sure no new echo_conns get added to the group. */
473 	ratelim_group = NULL;
474 
475 	/* This should get _everybody_ freed */
476 	while (n_echo_conns_open) {
477 		printf("waiting for %d conns\n", n_echo_conns_open);
478 		tv.tv_sec = 0;
479 		tv.tv_usec = 300000;
480 		event_base_loopexit(base, &tv);
481 		event_base_dispatch(base);
482 	}
483 
484 	if (group)
485 		bufferevent_rate_limit_group_free(group);
486 
487 	if (total_n_bev_checks) {
488 		printf("Average read bucket level: %f\n",
489 		    (double)total_rbucket_level/total_n_bev_checks);
490 		printf("Average write bucket level: %f\n",
491 		    (double)total_wbucket_level/total_n_bev_checks);
492 		printf("Highest read bucket level: %f\n",
493 		    (double)max_bucket_level);
494 		printf("Highest write bucket level: %f\n",
495 		    (double)min_bucket_level);
496 		printf("Average max-to-read: %f\n",
497 		    ((double)total_max_to_read)/total_n_bev_checks);
498 		printf("Average max-to-write: %f\n",
499 		    ((double)total_max_to_write)/total_n_bev_checks);
500 	}
501 	if (total_n_group_bev_checks) {
502 		printf("Average group read bucket level: %f\n",
503 		    ((double)total_group_rbucket_level)/total_n_group_bev_checks);
504 		printf("Average group write bucket level: %f\n",
505 		    ((double)total_group_wbucket_level)/total_n_group_bev_checks);
506 	}
507 
508 	total_received = 0;
509 	total_persec = 0.0;
510 	total_sq_persec = 0.0;
511 	for (i=0; i < cfg_n_connections; ++i) {
512 		double persec = states[i].received;
513 		persec /= cfg_duration;
514 		total_received += states[i].received;
515 		total_persec += persec;
516 		total_sq_persec += persec*persec;
517 		printf("%d: %f per second\n", i+1, persec);
518 	}
519 	printf("   total: %f per second\n",
520 	    ((double)total_received)/cfg_duration);
521 	if (expected_total_persec > 0) {
522 		double diff = expected_total_persec -
523 		    ((double)total_received/cfg_duration);
524 		printf("  [Off by %lf]\n", diff);
525 		if (cfg_grouplimit_tolerance > 0 &&
526 		    fabs(diff) > cfg_grouplimit_tolerance) {
527 			fprintf(stderr, "Group bandwidth out of bounds\n");
528 			ok = 0;
529 		}
530 	}
531 
532 	printf(" average: %f per second\n",
533 	    (((double)total_received)/cfg_duration)/cfg_n_connections);
534 	if (expected_avg_persec > 0) {
535 		double diff = expected_avg_persec - (((double)total_received)/cfg_duration)/cfg_n_connections;
536 		printf("  [Off by %lf]\n", diff);
537 		if (cfg_connlimit_tolerance > 0 &&
538 		    fabs(diff) > cfg_connlimit_tolerance) {
539 			fprintf(stderr, "Connection bandwidth out of bounds\n");
540 			ok = 0;
541 		}
542 	}
543 
544 	variance = total_sq_persec/cfg_n_connections - total_persec*total_persec/(cfg_n_connections*cfg_n_connections);
545 
546 	printf("  stddev: %f per second\n", sqrt(variance));
547 	if (cfg_stddev_tolerance > 0 &&
548 	    sqrt(variance) > cfg_stddev_tolerance) {
549 		fprintf(stderr, "Connection variance out of bounds\n");
550 		ok = 0;
551 	}
552 
553 	event_base_free(base);
554 	free(bevs);
555 	free(states);
556 
557 	return ok ? 0 : 1;
558 }
559 
560 static struct option {
561 	const char *name; int *ptr; int min; int isbool;
562 } options[] = {
563 	{ "-v", &cfg_verbose, 0, 1 },
564 	{ "-h", &cfg_help, 0, 1 },
565 	{ "-n", &cfg_n_connections, 1, 0 },
566 	{ "-d", &cfg_duration, 1, 0 },
567 	{ "-c", &cfg_connlimit, 0, 0 },
568 	{ "-g", &cfg_grouplimit, 0, 0 },
569 	{ "-G", &cfg_group_drain, -100000, 0 },
570 	{ "-t", &cfg_tick_msec, 10, 0 },
571 	{ "--min-share", &cfg_min_share, 0, 0 },
572 	{ "--check-connlimit", &cfg_connlimit_tolerance, 0, 0 },
573 	{ "--check-grouplimit", &cfg_grouplimit_tolerance, 0, 0 },
574 	{ "--check-stddev", &cfg_stddev_tolerance, 0, 0 },
575 #ifdef _WIN32
576 	{ "--iocp", &cfg_enable_iocp, 0, 1 },
577 #endif
578 	{ NULL, NULL, -1, 0 },
579 };
580 
581 static int
handle_option(int argc,char ** argv,int * i,const struct option * opt)582 handle_option(int argc, char **argv, int *i, const struct option *opt)
583 {
584 	long val;
585 	char *endptr = NULL;
586 	if (opt->isbool) {
587 		*opt->ptr = 1;
588 		return 0;
589 	}
590 	if (*i + 1 == argc) {
591 		fprintf(stderr, "Too few arguments to '%s'\n",argv[*i]);
592 		return -1;
593 	}
594 	val = strtol(argv[*i+1], &endptr, 10);
595 	if (*argv[*i+1] == '\0' || !endptr || *endptr != '\0') {
596 		fprintf(stderr, "Couldn't parse numeric value '%s'\n",
597 		    argv[*i+1]);
598 		return -1;
599 	}
600 	if (val < opt->min || val > 0x7fffffff) {
601 		fprintf(stderr, "Value '%s' is out-of-range'\n",
602 		    argv[*i+1]);
603 		return -1;
604 	}
605 	*opt->ptr = (int)val;
606 	++*i;
607 	return 0;
608 }
609 
610 static void
usage(void)611 usage(void)
612 {
613 	fprintf(stderr,
614 "test-ratelim [-v] [-n INT] [-d INT] [-c INT] [-g INT] [-t INT]\n\n"
615 "Pushes bytes through a number of possibly rate-limited connections, and\n"
616 "displays average throughput.\n\n"
617 "  -n INT: Number of connections to open (default: 30)\n"
618 "  -d INT: Duration of the test in seconds (default: 5 sec)\n");
619 	fprintf(stderr,
620 "  -c INT: Connection-rate limit applied to each connection in bytes per second\n"
621 "	   (default: None.)\n"
622 "  -g INT: Group-rate limit applied to sum of all usage in bytes per second\n"
623 "	   (default: None.)\n"
624 "  -G INT: drain INT bytes from the group limit every tick. (default: 0)\n"
625 "  -t INT: Granularity of timing, in milliseconds (default: 1000 msec)\n");
626 }
627 
628 int
main(int argc,char ** argv)629 main(int argc, char **argv)
630 {
631 	int i,j;
632 	double ratio;
633 
634 #ifdef _WIN32
635 	WORD wVersionRequested = MAKEWORD(2,2);
636 	WSADATA wsaData;
637 
638 	(void) WSAStartup(wVersionRequested, &wsaData);
639 #endif
640 
641 	evutil_weakrand_seed_(&weakrand_state, 0);
642 
643 #ifndef _WIN32
644 	if (signal(SIGPIPE, SIG_IGN) == SIG_ERR)
645 		return 1;
646 #endif
647 	for (i = 1; i < argc; ++i) {
648 		for (j = 0; options[j].name; ++j) {
649 			if (!strcmp(argv[i],options[j].name)) {
650 				if (handle_option(argc,argv,&i,&options[j])<0)
651 					return 1;
652 				goto again;
653 			}
654 		}
655 		fprintf(stderr, "Unknown option '%s'\n", argv[i]);
656 		usage();
657 		return 1;
658 	again:
659 		;
660 	}
661 	if (cfg_help) {
662 		usage();
663 		return 0;
664 	}
665 
666 	cfg_tick.tv_sec = cfg_tick_msec / 1000;
667 	cfg_tick.tv_usec = (cfg_tick_msec % 1000)*1000;
668 
669 	seconds_per_tick = ratio = cfg_tick_msec / 1000.0;
670 
671 	cfg_connlimit *= ratio;
672 	cfg_grouplimit *= ratio;
673 
674 	{
675 		struct timeval tv;
676 		evutil_gettimeofday(&tv, NULL);
677 #ifdef _WIN32
678 		srand(tv.tv_usec);
679 #else
680 		srandom(tv.tv_usec);
681 #endif
682 	}
683 
684 #ifndef EVENT__DISABLE_THREAD_SUPPORT
685 	evthread_enable_lock_debugging();
686 #endif
687 
688 	return test_ratelimiting();
689 }
690