xref: /iperf/src/iperf_client_api.c (revision 7bdd5b0e)
1 /*
2  * iperf, Copyright (c) 2014-2022, The Regents of the University of
3  * California, through Lawrence Berkeley National Laboratory (subject
4  * to receipt of any required approvals from the U.S. Dept. of
5  * Energy).  All rights reserved.
6  *
7  * If you have questions about your rights to use or distribute this
8  * software, please contact Berkeley Lab's Technology Transfer
9  * Department at [email protected].
10  *
11  * NOTICE.  This software is owned by the U.S. Department of Energy.
12  * As such, the U.S. Government has been granted for itself and others
13  * acting on its behalf a paid-up, nonexclusive, irrevocable,
14  * worldwide license in the Software to reproduce, prepare derivative
15  * works, and perform publicly and display publicly.  Beginning five
16  * (5) years after the date permission to assert copyright is obtained
17  * from the U.S. Department of Energy, and subject to any subsequent
18  * five (5) year renewals, the U.S. Government is granted for itself
19  * and others acting on its behalf a paid-up, nonexclusive,
20  * irrevocable, worldwide license in the Software to reproduce,
21  * prepare derivative works, distribute copies to the public, perform
22  * publicly and display publicly, and to permit others to do so.
23  *
24  * This code is distributed under a BSD style license, see the LICENSE
25  * file for complete information.
26  */
27 #include <errno.h>
28 #include <setjmp.h>
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <unistd.h>
33 #include <signal.h>
34 #include <sys/types.h>
35 #include <netinet/in.h>
36 #include <sys/select.h>
37 #include <sys/uio.h>
38 #include <arpa/inet.h>
39 
40 #include "iperf.h"
41 #include "iperf_api.h"
42 #include "iperf_util.h"
43 #include "iperf_locale.h"
44 #include "iperf_time.h"
45 #include "net.h"
46 #include "timer.h"
47 
48 #if defined(HAVE_TCP_CONGESTION)
49 #if !defined(TCP_CA_NAME_MAX)
50 #define TCP_CA_NAME_MAX 16
51 #endif /* TCP_CA_NAME_MAX */
52 #endif /* HAVE_TCP_CONGESTION */
53 
54 int
iperf_create_streams(struct iperf_test * test,int sender)55 iperf_create_streams(struct iperf_test *test, int sender)
56 {
57     if (NULL == test)
58     {
59         iperf_err(NULL, "No test\n");
60         return -1;
61     }
62     int i, s;
63 #if defined(HAVE_TCP_CONGESTION)
64     int saved_errno;
65 #endif /* HAVE_TCP_CONGESTION */
66     struct iperf_stream *sp;
67 
68     int orig_bind_port = test->bind_port;
69     for (i = 0; i < test->num_streams; ++i) {
70 
71         test->bind_port = orig_bind_port;
72 	if (orig_bind_port) {
73 	    test->bind_port += i;
74             // If Bidir make sure send and receive ports are different
75             if (!sender && test->mode == BIDIRECTIONAL)
76                 test->bind_port += test->num_streams;
77         }
78         s = test->protocol->connect(test);
79         test->bind_port = orig_bind_port;
80         if (s < 0)
81             return -1;
82 
83 #if defined(HAVE_TCP_CONGESTION)
84 	if (test->protocol->id == Ptcp) {
85 	    if (test->congestion) {
86 		if (setsockopt(s, IPPROTO_TCP, TCP_CONGESTION, test->congestion, strlen(test->congestion)) < 0) {
87 		    saved_errno = errno;
88 		    close(s);
89 		    errno = saved_errno;
90 		    i_errno = IESETCONGESTION;
91 		    return -1;
92 		}
93 	    }
94 	    {
95 		socklen_t len = TCP_CA_NAME_MAX;
96 		char ca[TCP_CA_NAME_MAX + 1];
97                 int rc;
98 		rc = getsockopt(s, IPPROTO_TCP, TCP_CONGESTION, ca, &len);
99                 if (rc < 0 && test->congestion) {
100 		    saved_errno = errno;
101 		    close(s);
102 		    errno = saved_errno;
103 		    i_errno = IESETCONGESTION;
104 		    return -1;
105 		}
106                 // Set actual used congestion alg, or set to unknown if could not get it
107                 if (rc < 0)
108                     test->congestion_used = strdup("unknown");
109                 else
110                     test->congestion_used = strdup(ca);
111 		if (test->debug) {
112 		    printf("Congestion algorithm is %s\n", test->congestion_used);
113 		}
114 	    }
115 	}
116 #endif /* HAVE_TCP_CONGESTION */
117 
118 	if (sender)
119 	    FD_SET(s, &test->write_set);
120 	else
121 	    FD_SET(s, &test->read_set);
122 	if (s > test->max_fd) test->max_fd = s;
123 
124         sp = iperf_new_stream(test, s, sender);
125         if (!sp)
126             return -1;
127 
128         /* Perform the new stream callback */
129         if (test->on_new_stream)
130             test->on_new_stream(sp);
131     }
132 
133     return 0;
134 }
135 
136 static void
test_timer_proc(TimerClientData client_data,struct iperf_time * nowP)137 test_timer_proc(TimerClientData client_data, struct iperf_time *nowP)
138 {
139     struct iperf_test *test = client_data.p;
140 
141     test->timer = NULL;
142     test->done = 1;
143 }
144 
145 static void
client_stats_timer_proc(TimerClientData client_data,struct iperf_time * nowP)146 client_stats_timer_proc(TimerClientData client_data, struct iperf_time *nowP)
147 {
148     struct iperf_test *test = client_data.p;
149 
150     if (test->done)
151         return;
152     if (test->stats_callback)
153 	test->stats_callback(test);
154 }
155 
156 static void
client_reporter_timer_proc(TimerClientData client_data,struct iperf_time * nowP)157 client_reporter_timer_proc(TimerClientData client_data, struct iperf_time *nowP)
158 {
159     struct iperf_test *test = client_data.p;
160 
161     if (test->done)
162         return;
163     if (test->reporter_callback)
164 	test->reporter_callback(test);
165 }
166 
167 static int
create_client_timers(struct iperf_test * test)168 create_client_timers(struct iperf_test * test)
169 {
170     struct iperf_time now;
171     TimerClientData cd;
172     if (NULL == test)
173     {
174         iperf_err(NULL, "No test\n");
175         i_errno = IEINITTEST;
176         return -1;
177     }
178 
179     if (iperf_time_now(&now) < 0) {
180 	i_errno = IEINITTEST;
181 	return -1;
182     }
183     cd.p = test;
184     test->timer = test->stats_timer = test->reporter_timer = NULL;
185     if (test->duration != 0) {
186 	test->done = 0;
187         test->timer = tmr_create(&now, test_timer_proc, cd, ( test->duration + test->omit ) * SEC_TO_US, 0);
188         if (test->timer == NULL) {
189             i_errno = IEINITTEST;
190             return -1;
191 	}
192     }
193     if (test->stats_interval != 0) {
194         test->stats_timer = tmr_create(&now, client_stats_timer_proc, cd, test->stats_interval * SEC_TO_US, 1);
195         if (test->stats_timer == NULL) {
196             i_errno = IEINITTEST;
197             return -1;
198 	}
199     }
200     if (test->reporter_interval != 0) {
201         test->reporter_timer = tmr_create(&now, client_reporter_timer_proc, cd, test->reporter_interval * SEC_TO_US, 1);
202         if (test->reporter_timer == NULL) {
203             i_errno = IEINITTEST;
204             return -1;
205 	}
206     }
207     return 0;
208 }
209 
210 static void
client_omit_timer_proc(TimerClientData client_data,struct iperf_time * nowP)211 client_omit_timer_proc(TimerClientData client_data, struct iperf_time *nowP)
212 {
213     struct iperf_test *test = client_data.p;
214 
215     test->omit_timer = NULL;
216     test->omitting = 0;
217     iperf_reset_stats(test);
218     if (test->verbose && !test->json_output && test->reporter_interval == 0)
219         iperf_printf(test, "%s", report_omit_done);
220 
221     /* Reset the timers. */
222     if (test->stats_timer != NULL)
223         tmr_reset(nowP, test->stats_timer);
224     if (test->reporter_timer != NULL)
225         tmr_reset(nowP, test->reporter_timer);
226 }
227 
228 static int
create_client_omit_timer(struct iperf_test * test)229 create_client_omit_timer(struct iperf_test * test)
230 {
231     struct iperf_time now;
232     TimerClientData cd;
233     if (NULL == test)
234     {
235         iperf_err(NULL, "No test\n");
236         return -1;
237     }
238 
239     if (test->omit == 0) {
240 	test->omit_timer = NULL;
241         test->omitting = 0;
242     } else {
243 	if (iperf_time_now(&now) < 0) {
244 	    i_errno = IEINITTEST;
245 	    return -1;
246 	}
247 	test->omitting = 1;
248 	cd.p = test;
249 	test->omit_timer = tmr_create(&now, client_omit_timer_proc, cd, test->omit * SEC_TO_US, 0);
250 	if (test->omit_timer == NULL) {
251 	    i_errno = IEINITTEST;
252 	    return -1;
253 	}
254     }
255     return 0;
256 }
257 
258 int
iperf_handle_message_client(struct iperf_test * test)259 iperf_handle_message_client(struct iperf_test *test)
260 {
261     int rval;
262     int32_t err;
263 
264     if (NULL == test)
265     {
266         iperf_err(NULL, "No test\n");
267 	i_errno = IEINITTEST;
268         return -1;
269     }
270     /*!!! Why is this read() and not Nread()? */
271     if ((rval = read(test->ctrl_sck, (char*) &test->state, sizeof(signed char))) <= 0) {
272         if (rval == 0) {
273             i_errno = IECTRLCLOSE;
274             return -1;
275         } else {
276             i_errno = IERECVMESSAGE;
277             return -1;
278         }
279     }
280 
281     switch (test->state) {
282         case PARAM_EXCHANGE:
283             if (iperf_exchange_parameters(test) < 0)
284                 return -1;
285             if (test->on_connect)
286                 test->on_connect(test);
287             break;
288         case CREATE_STREAMS:
289             if (test->mode == BIDIRECTIONAL)
290             {
291                 if (iperf_create_streams(test, 1) < 0)
292                     return -1;
293                 if (iperf_create_streams(test, 0) < 0)
294                     return -1;
295             }
296             else if (iperf_create_streams(test, test->mode) < 0)
297                 return -1;
298             break;
299         case TEST_START:
300             if (iperf_init_test(test) < 0)
301                 return -1;
302             if (create_client_timers(test) < 0)
303                 return -1;
304             if (create_client_omit_timer(test) < 0)
305                 return -1;
306 	    if (test->mode)
307 		if (iperf_create_send_timers(test) < 0)
308 		    return -1;
309             break;
310         case TEST_RUNNING:
311             break;
312         case EXCHANGE_RESULTS:
313             if (iperf_exchange_results(test) < 0)
314                 return -1;
315             break;
316         case DISPLAY_RESULTS:
317             if (test->on_test_finish)
318                 test->on_test_finish(test);
319             iperf_client_end(test);
320             break;
321         case IPERF_DONE:
322             break;
323         case SERVER_TERMINATE:
324             i_errno = IESERVERTERM;
325 
326 	    /*
327 	     * Temporarily be in DISPLAY_RESULTS phase so we can get
328 	     * ending summary statistics.
329 	     */
330 	    signed char oldstate = test->state;
331 	    cpu_util(test->cpu_util);
332 	    test->state = DISPLAY_RESULTS;
333 	    test->reporter_callback(test);
334 	    test->state = oldstate;
335             return -1;
336         case ACCESS_DENIED:
337             i_errno = IEACCESSDENIED;
338             return -1;
339         case SERVER_ERROR:
340             if (Nread(test->ctrl_sck, (char*) &err, sizeof(err), Ptcp) < 0) {
341                 i_errno = IECTRLREAD;
342                 return -1;
343             }
344 	    i_errno = ntohl(err);
345             if (Nread(test->ctrl_sck, (char*) &err, sizeof(err), Ptcp) < 0) {
346                 i_errno = IECTRLREAD;
347                 return -1;
348             }
349             errno = ntohl(err);
350             return -1;
351         default:
352             i_errno = IEMESSAGE;
353             return -1;
354     }
355 
356     return 0;
357 }
358 
359 
360 
361 /* iperf_connect -- client to server connection function */
362 int
iperf_connect(struct iperf_test * test)363 iperf_connect(struct iperf_test *test)
364 {
365     int opt;
366     socklen_t len;
367 
368     if (NULL == test)
369     {
370         iperf_err(NULL, "No test\n");
371         return -1;
372     }
373     FD_ZERO(&test->read_set);
374     FD_ZERO(&test->write_set);
375 
376     make_cookie(test->cookie);
377 
378     /* Create and connect the control channel */
379     if (test->ctrl_sck < 0)
380 	// Create the control channel using an ephemeral port
381 	test->ctrl_sck = netdial(test->settings->domain, Ptcp, test->bind_address, test->bind_dev, 0, test->server_hostname, test->server_port, test->settings->connect_timeout);
382     if (test->ctrl_sck < 0) {
383         i_errno = IECONNECT;
384         return -1;
385     }
386 
387     // set TCP_NODELAY for lower latency on control messages
388     int flag = 1;
389     if (setsockopt(test->ctrl_sck, IPPROTO_TCP, TCP_NODELAY, (char *) &flag, sizeof(int))) {
390         i_errno = IESETNODELAY;
391         return -1;
392     }
393 
394 #if defined(HAVE_TCP_USER_TIMEOUT)
395     if ((opt = test->settings->snd_timeout)) {
396         if (setsockopt(test->ctrl_sck, IPPROTO_TCP, TCP_USER_TIMEOUT, &opt, sizeof(opt)) < 0) {
397         i_errno = IESETUSERTIMEOUT;
398         return -1;
399         }
400     }
401 #endif /* HAVE_TCP_USER_TIMEOUT */
402 
403     if (Nwrite(test->ctrl_sck, test->cookie, COOKIE_SIZE, Ptcp) < 0) {
404         i_errno = IESENDCOOKIE;
405         return -1;
406     }
407 
408     FD_SET(test->ctrl_sck, &test->read_set);
409     if (test->ctrl_sck > test->max_fd) test->max_fd = test->ctrl_sck;
410 
411     len = sizeof(opt);
412     if (getsockopt(test->ctrl_sck, IPPROTO_TCP, TCP_MAXSEG, &opt, &len) < 0) {
413         test->ctrl_sck_mss = 0;
414     }
415     else {
416         if (opt > 0 && opt <= MAX_UDP_BLOCKSIZE) {
417             test->ctrl_sck_mss = opt;
418         }
419         else {
420             char str[WARN_STR_LEN];
421             snprintf(str, sizeof(str),
422                      "Ignoring nonsense TCP MSS %d", opt);
423             warning(str);
424 
425             test->ctrl_sck_mss = 0;
426         }
427     }
428 
429     if (test->verbose) {
430 	printf("Control connection MSS %d\n", test->ctrl_sck_mss);
431     }
432 
433     /*
434      * If we're doing a UDP test and the block size wasn't explicitly
435      * set, then use the known MSS of the control connection to pick
436      * an appropriate default.  If we weren't able to get the
437      * MSS for some reason, then default to something that should
438      * work on non-jumbo-frame Ethernet networks.  The goal is to
439      * pick a reasonable default that is large but should get from
440      * sender to receiver without any IP fragmentation.
441      *
442      * We assume that the control connection is routed the same as the
443      * data packets (thus has the same PMTU).  Also in the case of
444      * --reverse tests, we assume that the MTU is the same in both
445      * directions.  Note that even if the algorithm guesses wrong,
446      * the user always has the option to override.
447      */
448     if (test->protocol->id == Pudp) {
449 	if (test->settings->blksize == 0) {
450 	    if (test->ctrl_sck_mss) {
451 		test->settings->blksize = test->ctrl_sck_mss;
452 	    }
453 	    else {
454 		test->settings->blksize = DEFAULT_UDP_BLKSIZE;
455 	    }
456 	    if (test->verbose) {
457 		printf("Setting UDP block size to %d\n", test->settings->blksize);
458 	    }
459 	}
460 
461 	/*
462 	 * Regardless of whether explicitly or implicitly set, if the
463 	 * block size is larger than the MSS, print a warning.
464 	 */
465 	if (test->ctrl_sck_mss > 0 &&
466 	    test->settings->blksize > test->ctrl_sck_mss) {
467 	    char str[WARN_STR_LEN];
468 	    snprintf(str, sizeof(str),
469 		     "UDP block size %d exceeds TCP MSS %d, may result in fragmentation / drops", test->settings->blksize, test->ctrl_sck_mss);
470 	    warning(str);
471 	}
472     }
473 
474     return 0;
475 }
476 
477 
478 int
iperf_client_end(struct iperf_test * test)479 iperf_client_end(struct iperf_test *test)
480 {
481     if (NULL == test)
482     {
483         iperf_err(NULL, "No test\n");
484         return -1;
485     }
486     struct iperf_stream *sp;
487 
488     /* Close all stream sockets */
489     SLIST_FOREACH(sp, &test->streams, streams) {
490         close(sp->socket);
491     }
492 
493     /* show final summary */
494     test->reporter_callback(test);
495 
496     /* Send response only if no error in server */
497     if (test->state > 0) {
498         if (iperf_set_send_state(test, IPERF_DONE) != 0)
499             return -1;
500     }
501 
502     /* Close control socket */
503     if (test->ctrl_sck >= 0)
504         close(test->ctrl_sck);
505 
506     return 0;
507 }
508 
509 
510 int
iperf_run_client(struct iperf_test * test)511 iperf_run_client(struct iperf_test * test)
512 {
513     int startup;
514     int result = 0;
515     fd_set read_set, write_set;
516     struct iperf_time now;
517     struct timeval* timeout = NULL;
518     struct iperf_stream *sp;
519     struct iperf_time last_receive_time;
520     struct iperf_time diff_time;
521     struct timeval used_timeout;
522     int64_t t_usecs;
523     int64_t timeout_us;
524     int64_t rcv_timeout_us;
525 
526     if (NULL == test)
527     {
528         iperf_err(NULL, "No test\n");
529         return -1;
530     }
531 
532     if (test->logfile)
533         if (iperf_open_logfile(test) < 0)
534             return -1;
535 
536     if (test->affinity != -1)
537 	if (iperf_setaffinity(test, test->affinity) != 0)
538 	    return -1;
539 
540     if (test->json_output)
541 	if (iperf_json_start(test) < 0)
542 	    return -1;
543 
544     if (test->json_output) {
545 	cJSON_AddItemToObject(test->json_start, "version", cJSON_CreateString(version));
546 	cJSON_AddItemToObject(test->json_start, "system_info", cJSON_CreateString(get_system_info()));
547     } else if (test->verbose) {
548 	iperf_printf(test, "%s\n", version);
549 	iperf_printf(test, "%s", "");
550 	iperf_printf(test, "%s\n", get_system_info());
551 	iflush(test);
552     }
553 
554     /* Start the client and connect to the server */
555     if (iperf_connect(test) < 0)
556         goto cleanup_and_fail;
557 
558     /* Begin calculating CPU utilization */
559     cpu_util(NULL);
560     if (test->mode != SENDER)
561         rcv_timeout_us = (test->settings->rcv_timeout.secs * SEC_TO_US) + test->settings->rcv_timeout.usecs;
562     else
563         rcv_timeout_us = 0;
564 
565     startup = 1;
566     while (test->state != IPERF_DONE) {
567 	memcpy(&read_set, &test->read_set, sizeof(fd_set));
568 	memcpy(&write_set, &test->write_set, sizeof(fd_set));
569 	iperf_time_now(&now);
570 	timeout = tmr_timeout(&now);
571 
572         // In reverse active mode client ensures data is received
573         if (test->state == TEST_RUNNING && rcv_timeout_us > 0) {
574             timeout_us = -1;
575             if (timeout != NULL) {
576                 used_timeout.tv_sec = timeout->tv_sec;
577                 used_timeout.tv_usec = timeout->tv_usec;
578                 timeout_us = (timeout->tv_sec * SEC_TO_US) + timeout->tv_usec;
579             }
580             if (timeout_us < 0 || timeout_us > rcv_timeout_us) {
581                 used_timeout.tv_sec = test->settings->rcv_timeout.secs;
582                 used_timeout.tv_usec = test->settings->rcv_timeout.usecs;
583             }
584             timeout = &used_timeout;
585         }
586 
587 	result = select(test->max_fd + 1, &read_set, &write_set, NULL, timeout);
588 	if (result < 0 && errno != EINTR) {
589   	    i_errno = IESELECT;
590 	    goto cleanup_and_fail;
591         } else if (result == 0 && test->state == TEST_RUNNING && rcv_timeout_us > 0) {
592             // If nothing was received in non-reverse running state then probably something got stack -
593             // either client, server or network, and test should be terminated.
594             iperf_time_now(&now);
595             if (iperf_time_diff(&now, &last_receive_time, &diff_time) == 0) {
596                 t_usecs = iperf_time_in_usecs(&diff_time);
597                 if (t_usecs > rcv_timeout_us) {
598                     i_errno = IENOMSG;
599                     goto cleanup_and_fail;
600                 }
601 
602             }
603         }
604 
605 	if (result > 0) {
606             if (rcv_timeout_us > 0) {
607                 iperf_time_now(&last_receive_time);
608             }
609 	    if (FD_ISSET(test->ctrl_sck, &read_set)) {
610  	        if (iperf_handle_message_client(test) < 0) {
611 		    goto cleanup_and_fail;
612 		}
613 		FD_CLR(test->ctrl_sck, &read_set);
614 	    }
615 	}
616 
617 	if (test->state == TEST_RUNNING) {
618 
619 	    /* Is this our first time really running? */
620 	    if (startup) {
621 	        startup = 0;
622 
623 		// Set non-blocking for non-UDP tests
624 		if (test->protocol->id != Pudp) {
625 		    SLIST_FOREACH(sp, &test->streams, streams) {
626 			setnonblocking(sp->socket, 1);
627 		    }
628 		}
629 	    }
630 
631 
632 	    if (test->mode == BIDIRECTIONAL)
633 	    {
634                 if (iperf_send(test, &write_set) < 0)
635                     goto cleanup_and_fail;
636                 if (iperf_recv(test, &read_set) < 0)
637                     goto cleanup_and_fail;
638 	    } else if (test->mode == SENDER) {
639                 // Regular mode. Client sends.
640                 if (iperf_send(test, &write_set) < 0)
641                     goto cleanup_and_fail;
642 	    } else {
643                 // Reverse mode. Client receives.
644                 if (iperf_recv(test, &read_set) < 0)
645                     goto cleanup_and_fail;
646 	    }
647 
648 
649             /* Run the timers. */
650             iperf_time_now(&now);
651             tmr_run(&now);
652 
653 	    /*
654 	     * Is the test done yet?  We have to be out of omitting
655 	     * mode, and then we have to have fulfilled one of the
656 	     * ending criteria, either by times, bytes, or blocks.
657 	     * The bytes and blocks tests needs to handle both the
658 	     * cases of the client being the sender and the client
659 	     * being the receiver.
660 	     */
661 	    if ((!test->omitting) &&
662 	        (test->done ||
663 	         (test->settings->bytes != 0 && (test->bytes_sent >= test->settings->bytes ||
664 						 test->bytes_received >= test->settings->bytes)) ||
665 	         (test->settings->blocks != 0 && (test->blocks_sent >= test->settings->blocks ||
666 						  test->blocks_received >= test->settings->blocks)))) {
667 
668 		// Unset non-blocking for non-UDP tests
669 		if (test->protocol->id != Pudp) {
670 		    SLIST_FOREACH(sp, &test->streams, streams) {
671 			setnonblocking(sp->socket, 0);
672 		    }
673 		}
674 
675 		/* Yes, done!  Send TEST_END. */
676 		test->done = 1;
677 		cpu_util(test->cpu_util);
678 		test->stats_callback(test);
679 		if (iperf_set_send_state(test, TEST_END) != 0)
680                     goto cleanup_and_fail;
681 	    }
682 	}
683 	// If we're in reverse mode, continue draining the data
684 	// connection(s) even if test is over.  This prevents a
685 	// deadlock where the server side fills up its pipe(s)
686 	// and gets blocked, so it can't receive state changes
687 	// from the client side.
688 	else if (test->mode == RECEIVER && test->state == TEST_END) {
689 	    if (iperf_recv(test, &read_set) < 0)
690 		goto cleanup_and_fail;
691 	}
692     }
693 
694     if (test->json_output) {
695 	if (iperf_json_finish(test) < 0)
696 	    return -1;
697     } else {
698 	iperf_printf(test, "\n");
699 	iperf_printf(test, "%s", report_done);
700     }
701 
702     iflush(test);
703 
704     return 0;
705 
706   cleanup_and_fail:
707     iperf_client_end(test);
708     if (test->json_output) {
709         cJSON_AddStringToObject(test->json_top, "error", iperf_strerror(i_errno));
710         iperf_json_finish(test);
711         iflush(test);
712         // Return 0 and not -1 since all terminating function were done here.
713         // Also prevents error message logging outside the already closed JSON output.
714         return 0;
715     }
716     iflush(test);
717     return -1;
718 }
719