xref: /freebsd/sbin/ggate/ggatec/ggatec.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2004 Pawel Jakub Dawidek <pjd@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <stdint.h>
32 #include <fcntl.h>
33 #include <unistd.h>
34 #include <string.h>
35 #include <ctype.h>
36 #include <inttypes.h>
37 #include <libgen.h>
38 #include <pthread.h>
39 #include <signal.h>
40 #include <err.h>
41 #include <errno.h>
42 #include <assert.h>
43 
44 #include <sys/param.h>
45 #include <sys/ioctl.h>
46 #include <sys/socket.h>
47 #include <sys/sysctl.h>
48 #include <sys/syslog.h>
49 #include <sys/time.h>
50 #include <sys/bio.h>
51 #include <netinet/in.h>
52 #include <netinet/tcp.h>
53 #include <arpa/inet.h>
54 
55 #include <geom/gate/g_gate.h>
56 #include "ggate.h"
57 
58 
59 static enum { UNSET, CREATE, DESTROY, LIST, RESCUE } action = UNSET;
60 
61 static const char *path = NULL;
62 static const char *host = NULL;
63 static int unit = G_GATE_UNIT_AUTO;
64 static unsigned flags = 0;
65 static int force = 0;
66 static unsigned queue_size = G_GATE_QUEUE_SIZE;
67 static unsigned port = G_GATE_PORT;
68 static off_t mediasize;
69 static unsigned sectorsize = 0;
70 static unsigned timeout = G_GATE_TIMEOUT;
71 static int sendfd, recvfd;
72 static uint32_t token;
73 static pthread_t sendtd, recvtd;
74 static int reconnect;
75 static int initialbuffersize = 131072;
76 
77 static void
78 usage(void)
79 {
80 
81 	fprintf(stderr, "usage: %s create [-nv] [-o <ro|wo|rw>] [-p port] "
82 	    "[-q queue_size] [-R rcvbuf] [-S sndbuf] [-s sectorsize] "
83 	    "[-t timeout] [-u unit] <host> <path>\n", getprogname());
84 	fprintf(stderr, "       %s rescue [-nv] [-o <ro|wo|rw>] [-p port] "
85 	    "[-R rcvbuf] [-S sndbuf] <-u unit> <host> <path>\n", getprogname());
86 	fprintf(stderr, "       %s destroy [-f] <-u unit>\n", getprogname());
87 	fprintf(stderr, "       %s list [-v] [-u unit]\n", getprogname());
88 	exit(EXIT_FAILURE);
89 }
90 
91 static void *
92 send_thread(void *arg __unused)
93 {
94 	struct g_gate_ctl_io ggio;
95 	struct g_gate_hdr hdr;
96 	size_t buf_capacity;
97 	ssize_t numbytesprocd;
98 	int error;
99 	char *newbuf;
100 
101 	g_gate_log(LOG_NOTICE, "%s: started!", __func__);
102 
103 	buf_capacity = initialbuffersize;
104 
105 	ggio.gctl_version = G_GATE_VERSION;
106 	ggio.gctl_unit = unit;
107 	ggio.gctl_data = malloc(buf_capacity);
108 	if (ggio.gctl_data == NULL) {
109 		g_gate_log(LOG_ERR, "%s: Cannot alloc buffer.", __func__);
110 		pthread_exit(NULL);
111 	}
112 
113 	for (;;) {
114 		ggio.gctl_length = buf_capacity;
115 		ggio.gctl_error = 0;
116 		g_gate_ioctl(G_GATE_CMD_START, &ggio);
117 		error = ggio.gctl_error;
118 		switch (error) {
119 		case 0:
120 			break;
121 		case ECANCELED:
122 			if (reconnect)
123 				break;
124 			/* Exit gracefully. */
125 			g_gate_close_device();
126 			exit(EXIT_SUCCESS);
127 
128 		case ENOMEM:
129 		{
130 			/* Buffer too small. */
131 			g_gate_log(LOG_DEBUG, "buffer too small. new size: %u",
132 			    ggio.gctl_length);
133 			newbuf = malloc(ggio.gctl_length);
134 			if (newbuf != NULL) {
135 				free(ggio.gctl_data);
136 				ggio.gctl_data = newbuf;
137 				buf_capacity = ggio.gctl_length;
138 				continue;
139 			}
140 			/* FALLTHROUGH */
141 		}
142 
143 		case ENXIO:
144 		default:
145 			g_gate_xlog("ioctl(/dev/%s): %s.", G_GATE_CTL_NAME,
146 			    strerror(error));
147 		}
148 
149 		if (reconnect)
150 			break;
151 
152 		switch (ggio.gctl_cmd) {
153 		case BIO_READ:
154 			hdr.gh_cmd = GGATE_CMD_READ;
155 			break;
156 		case BIO_WRITE:
157 			hdr.gh_cmd = GGATE_CMD_WRITE;
158 			break;
159 		case BIO_FLUSH:
160 			hdr.gh_cmd = GGATE_CMD_FLUSH;
161 			break;
162 		default:
163 			g_gate_log(LOG_NOTICE, "Unknown gctl_cmd: %i",
164 			    ggio.gctl_cmd);
165 			ggio.gctl_error = EOPNOTSUPP;
166 			g_gate_ioctl(G_GATE_CMD_DONE, &ggio);
167 			continue;
168 		}
169 
170 		hdr.gh_seq = ggio.gctl_seq;
171 		hdr.gh_offset = ggio.gctl_offset;
172 		hdr.gh_length = ggio.gctl_length;
173 		hdr.gh_error = 0;
174 		g_gate_swap2n_hdr(&hdr);
175 
176 		numbytesprocd = g_gate_send(sendfd, &hdr, sizeof(hdr), MSG_NOSIGNAL);
177 		g_gate_log(LOG_DEBUG, "Sent hdr packet.");
178 		g_gate_swap2h_hdr(&hdr);
179 		if (reconnect)
180 			break;
181 		if (numbytesprocd != sizeof(hdr)) {
182 			g_gate_log(LOG_ERR, "Lost connection 1.");
183 			reconnect = 1;
184 			pthread_kill(recvtd, SIGUSR1);
185 			break;
186 		}
187 
188 		if (hdr.gh_cmd == GGATE_CMD_WRITE) {
189 			numbytesprocd = g_gate_send(sendfd, ggio.gctl_data,
190 			    ggio.gctl_length, MSG_NOSIGNAL);
191 			if (reconnect)
192 				break;
193 			if (numbytesprocd != ggio.gctl_length) {
194 				g_gate_log(LOG_ERR, "Lost connection 2 (%zd != %zd).",
195 				    numbytesprocd, (ssize_t)ggio.gctl_length);
196 				reconnect = 1;
197 				pthread_kill(recvtd, SIGUSR1);
198 				break;
199 			}
200 			g_gate_log(LOG_DEBUG, "Sent %zd bytes (offset=%"
201 			    PRIu64 ", length=%" PRIu32 ").", numbytesprocd,
202 			    hdr.gh_offset, hdr.gh_length);
203 		}
204 	}
205 	g_gate_log(LOG_DEBUG, "%s: Died.", __func__);
206 	return (NULL);
207 }
208 
209 static void *
210 recv_thread(void *arg __unused)
211 {
212 	struct g_gate_ctl_io ggio;
213 	struct g_gate_hdr hdr;
214 	ssize_t buf_capacity;
215 	ssize_t numbytesprocd;
216 	char *newbuf;
217 
218 	g_gate_log(LOG_NOTICE, "%s: started!", __func__);
219 
220 	buf_capacity = initialbuffersize;
221 
222 	ggio.gctl_version = G_GATE_VERSION;
223 	ggio.gctl_unit = unit;
224 	ggio.gctl_data = malloc(buf_capacity);
225 	if (ggio.gctl_data == NULL) {
226 		g_gate_log(LOG_ERR, "%s: Cannot alloc buffer.", __func__);
227 		pthread_exit(NULL);
228 	}
229 
230 	for (;;) {
231 		numbytesprocd = g_gate_recv(recvfd, &hdr, sizeof(hdr), MSG_WAITALL);
232 		if (reconnect)
233 			break;
234 		g_gate_swap2h_hdr(&hdr);
235 		if (numbytesprocd != sizeof(hdr)) {
236 			if (numbytesprocd == -1 && errno == EAGAIN)
237 				continue;
238 			g_gate_log(LOG_ERR, "Lost connection 3.");
239 			reconnect = 1;
240 			pthread_kill(sendtd, SIGUSR1);
241 			break;
242 		}
243 		g_gate_log(LOG_DEBUG, "Received hdr packet.");
244 
245 		ggio.gctl_seq = hdr.gh_seq;
246 		ggio.gctl_cmd = hdr.gh_cmd;
247 		ggio.gctl_offset = hdr.gh_offset;
248 		ggio.gctl_length = hdr.gh_length;
249 		ggio.gctl_error = hdr.gh_error;
250 
251 		if (ggio.gctl_length > buf_capacity) {
252 			newbuf = malloc(ggio.gctl_length);
253 			if (newbuf != NULL) {
254 				free(ggio.gctl_data);
255 				ggio.gctl_data = newbuf;
256 				buf_capacity = ggio.gctl_length;
257 			} else {
258 				g_gate_log(LOG_ERR, "Received too big response: %zd",
259 				    ggio.gctl_length);
260 				break;
261 			}
262 		}
263 
264 		if (ggio.gctl_error == 0 && ggio.gctl_cmd == GGATE_CMD_READ) {
265 			numbytesprocd = g_gate_recv(recvfd, ggio.gctl_data,
266 			    ggio.gctl_length, MSG_WAITALL);
267 			if (reconnect)
268 				break;
269 			g_gate_log(LOG_DEBUG, "Received data packet.");
270 			if (numbytesprocd != ggio.gctl_length) {
271 				g_gate_log(LOG_ERR, "Lost connection 4.");
272 				reconnect = 1;
273 				pthread_kill(sendtd, SIGUSR1);
274 				break;
275 			}
276 			g_gate_log(LOG_DEBUG, "Received %d bytes (offset=%"
277 			    PRIu64 ", length=%" PRIu32 ").", numbytesprocd,
278 			    hdr.gh_offset, hdr.gh_length);
279 		}
280 
281 		g_gate_ioctl(G_GATE_CMD_DONE, &ggio);
282 	}
283 	g_gate_log(LOG_DEBUG, "%s: Died.", __func__);
284 	pthread_exit(NULL);
285 }
286 
287 static int
288 handshake(int dir)
289 {
290 	struct g_gate_version ver;
291 	struct g_gate_cinit cinit;
292 	struct g_gate_sinit sinit;
293 	struct sockaddr_in serv;
294 	int sfd;
295 
296 	/*
297 	 * Do the network stuff.
298 	 */
299 	bzero(&serv, sizeof(serv));
300 	serv.sin_family = AF_INET;
301 	serv.sin_addr.s_addr = g_gate_str2ip(host);
302 	if (serv.sin_addr.s_addr == INADDR_NONE) {
303 		g_gate_log(LOG_DEBUG, "Invalid IP/host name: %s.", host);
304 		return (-1);
305 	}
306 	serv.sin_port = htons(port);
307 	sfd = socket(AF_INET, SOCK_STREAM, 0);
308 	if (sfd == -1) {
309 		g_gate_log(LOG_DEBUG, "Cannot open socket: %s.",
310 		    strerror(errno));
311 		return (-1);
312 	}
313 
314 	g_gate_socket_settings(sfd);
315 
316 	if (connect(sfd, (struct sockaddr *)&serv, sizeof(serv)) == -1) {
317 		g_gate_log(LOG_DEBUG, "Cannot connect to server: %s.",
318 		    strerror(errno));
319 		close(sfd);
320 		return (-1);
321 	}
322 
323 	g_gate_log(LOG_INFO, "Connected to the server: %s:%d.", host, port);
324 
325 	/*
326 	 * Create and send version packet.
327 	 */
328 	g_gate_log(LOG_DEBUG, "Sending version packet.");
329 	assert(strlen(GGATE_MAGIC) == sizeof(ver.gv_magic));
330 	bcopy(GGATE_MAGIC, ver.gv_magic, sizeof(ver.gv_magic));
331 	ver.gv_version = GGATE_VERSION;
332 	ver.gv_error = 0;
333 	g_gate_swap2n_version(&ver);
334 	if (g_gate_send(sfd, &ver, sizeof(ver), MSG_NOSIGNAL) == -1) {
335 		g_gate_log(LOG_DEBUG, "Error while sending version packet: %s.",
336 		    strerror(errno));
337 		close(sfd);
338 		return (-1);
339 	}
340 	bzero(&ver, sizeof(ver));
341 	if (g_gate_recv(sfd, &ver, sizeof(ver), MSG_WAITALL) == -1) {
342 		g_gate_log(LOG_DEBUG, "Error while receiving data: %s.",
343 		    strerror(errno));
344 		close(sfd);
345 		return (-1);
346 	}
347 	if (ver.gv_error != 0) {
348 		g_gate_log(LOG_DEBUG, "Version verification problem: %s.",
349 		    strerror(errno));
350 		close(sfd);
351 		return (-1);
352 	}
353 
354 	/*
355 	 * Create and send initial packet.
356 	 */
357 	g_gate_log(LOG_DEBUG, "Sending initial packet.");
358 	if (strlcpy(cinit.gc_path, path, sizeof(cinit.gc_path)) >=
359 	    sizeof(cinit.gc_path)) {
360 		g_gate_log(LOG_DEBUG, "Path name too long.");
361 		close(sfd);
362 		return (-1);
363 	}
364 	cinit.gc_flags = flags | dir;
365 	cinit.gc_token = token;
366 	cinit.gc_nconn = 2;
367 	g_gate_swap2n_cinit(&cinit);
368 	if (g_gate_send(sfd, &cinit, sizeof(cinit), MSG_NOSIGNAL) == -1) {
369 	        g_gate_log(LOG_DEBUG, "Error while sending initial packet: %s.",
370 		    strerror(errno));
371 		close(sfd);
372 		return (-1);
373 	}
374 	g_gate_swap2h_cinit(&cinit);
375 
376 	/*
377 	 * Receiving initial packet from server.
378 	 */
379 	g_gate_log(LOG_DEBUG, "Receiving initial packet.");
380 	if (g_gate_recv(sfd, &sinit, sizeof(sinit), MSG_WAITALL) == -1) {
381 		g_gate_log(LOG_DEBUG, "Error while receiving data: %s.",
382 		    strerror(errno));
383 		close(sfd);
384 		return (-1);
385 	}
386 	g_gate_swap2h_sinit(&sinit);
387 	if (sinit.gs_error != 0) {
388 	        g_gate_log(LOG_DEBUG, "Error from server: %s.",
389 		    strerror(sinit.gs_error));
390 		close(sfd);
391 		return (-1);
392 	}
393 	g_gate_log(LOG_DEBUG, "Received initial packet.");
394 
395 	mediasize = sinit.gs_mediasize;
396 	if (sectorsize == 0)
397 		sectorsize = sinit.gs_sectorsize;
398 
399 	return (sfd);
400 }
401 
402 static void
403 mydaemon(void)
404 {
405 
406 	if (g_gate_verbose > 0)
407 		return;
408 	if (daemon(0, 0) == 0)
409 		return;
410 	if (action == CREATE)
411 		g_gate_destroy(unit, 1);
412 	err(EXIT_FAILURE, "Cannot daemonize");
413 }
414 
415 static int
416 g_gatec_connect(void)
417 {
418 
419 	token = arc4random();
420 	/*
421 	 * Our receive descriptor is connected to the send descriptor on the
422 	 * server side.
423 	 */
424 	recvfd = handshake(GGATE_FLAG_SEND);
425 	if (recvfd == -1)
426 		return (0);
427 	/*
428 	 * Our send descriptor is connected to the receive descriptor on the
429 	 * server side.
430 	 */
431 	sendfd = handshake(GGATE_FLAG_RECV);
432 	if (sendfd == -1)
433 		return (0);
434 	return (1);
435 }
436 
437 static void
438 g_gatec_start(void)
439 {
440 	int error;
441 
442 	reconnect = 0;
443 	error = pthread_create(&recvtd, NULL, recv_thread, NULL);
444 	if (error != 0) {
445 		g_gate_destroy(unit, 1);
446 		g_gate_xlog("pthread_create(recv_thread): %s.",
447 		    strerror(error));
448 	}
449 	sendtd = pthread_self();
450 	send_thread(NULL);
451 	/* Disconnected. */
452 	close(sendfd);
453 	close(recvfd);
454 }
455 
456 static void
457 signop(int sig __unused)
458 {
459 
460 	/* Do nothing. */
461 }
462 
463 static void
464 g_gatec_loop(void)
465 {
466 	struct g_gate_ctl_cancel ggioc;
467 
468 	signal(SIGUSR1, signop);
469 	for (;;) {
470 		g_gatec_start();
471 		g_gate_log(LOG_NOTICE, "Disconnected [%s %s]. Connecting...",
472 		    host, path);
473 		while (!g_gatec_connect()) {
474 			sleep(2);
475 			g_gate_log(LOG_NOTICE, "Connecting [%s %s]...", host,
476 			    path);
477 		}
478 		ggioc.gctl_version = G_GATE_VERSION;
479 		ggioc.gctl_unit = unit;
480 		ggioc.gctl_seq = 0;
481 		g_gate_ioctl(G_GATE_CMD_CANCEL, &ggioc);
482 	}
483 }
484 
485 static void
486 g_gatec_create(void)
487 {
488 	struct g_gate_ctl_create ggioc;
489 
490 	if (!g_gatec_connect())
491 		g_gate_xlog("Cannot connect: %s.", strerror(errno));
492 
493 	/*
494 	 * Ok, got both sockets, time to create provider.
495 	 */
496 	memset(&ggioc, 0, sizeof(ggioc));
497 	ggioc.gctl_version = G_GATE_VERSION;
498 	ggioc.gctl_mediasize = mediasize;
499 	ggioc.gctl_sectorsize = sectorsize;
500 	ggioc.gctl_flags = flags;
501 	ggioc.gctl_maxcount = queue_size;
502 	ggioc.gctl_timeout = timeout;
503 	ggioc.gctl_unit = unit;
504 	snprintf(ggioc.gctl_info, sizeof(ggioc.gctl_info), "%s:%u %s", host,
505 	    port, path);
506 	g_gate_ioctl(G_GATE_CMD_CREATE, &ggioc);
507 	if (unit == -1) {
508 		printf("%s%u\n", G_GATE_PROVIDER_NAME, ggioc.gctl_unit);
509 		fflush(stdout);
510 	}
511 	unit = ggioc.gctl_unit;
512 
513 	mydaemon();
514 	g_gatec_loop();
515 }
516 
517 static void
518 g_gatec_rescue(void)
519 {
520 	struct g_gate_ctl_cancel ggioc;
521 
522 	if (!g_gatec_connect())
523 		g_gate_xlog("Cannot connect: %s.", strerror(errno));
524 
525 	ggioc.gctl_version = G_GATE_VERSION;
526 	ggioc.gctl_unit = unit;
527 	ggioc.gctl_seq = 0;
528 	g_gate_ioctl(G_GATE_CMD_CANCEL, &ggioc);
529 
530 	mydaemon();
531 	g_gatec_loop();
532 }
533 
534 static void
535 init_initial_buffer_size(void)
536 {
537 	int value;
538 	size_t intsize;
539 	intsize = sizeof(initialbuffersize);
540 	if (sysctlbyname("kern.maxphys", &value, &intsize, NULL, 0) == 0)
541 		initialbuffersize = value;
542 }
543 
544 int
545 main(int argc, char *argv[])
546 {
547 
548 	if (argc < 2)
549 		usage();
550 	if (strcasecmp(argv[1], "create") == 0)
551 		action = CREATE;
552 	else if (strcasecmp(argv[1], "destroy") == 0)
553 		action = DESTROY;
554 	else if (strcasecmp(argv[1], "list") == 0)
555 		action = LIST;
556 	else if (strcasecmp(argv[1], "rescue") == 0)
557 		action = RESCUE;
558 	else
559 		usage();
560 	argc -= 1;
561 	argv += 1;
562 	for (;;) {
563 		int ch;
564 
565 		ch = getopt(argc, argv, "fno:p:q:R:S:s:t:u:v");
566 		if (ch == -1)
567 			break;
568 		switch (ch) {
569 		case 'f':
570 			if (action != DESTROY)
571 				usage();
572 			force = 1;
573 			break;
574 		case 'n':
575 			if (action != CREATE && action != RESCUE)
576 				usage();
577 			nagle = 0;
578 			break;
579 		case 'o':
580 			if (action != CREATE && action != RESCUE)
581 				usage();
582 			if (strcasecmp("ro", optarg) == 0)
583 				flags = G_GATE_FLAG_READONLY;
584 			else if (strcasecmp("wo", optarg) == 0)
585 				flags = G_GATE_FLAG_WRITEONLY;
586 			else if (strcasecmp("rw", optarg) == 0)
587 				flags = 0;
588 			else {
589 				errx(EXIT_FAILURE,
590 				    "Invalid argument for '-o' option.");
591 			}
592 			break;
593 		case 'p':
594 			if (action != CREATE && action != RESCUE)
595 				usage();
596 			errno = 0;
597 			port = strtoul(optarg, NULL, 10);
598 			if (port == 0 && errno != 0)
599 				errx(EXIT_FAILURE, "Invalid port.");
600 			break;
601 		case 'q':
602 			if (action != CREATE)
603 				usage();
604 			errno = 0;
605 			queue_size = strtoul(optarg, NULL, 10);
606 			if (queue_size == 0 && errno != 0)
607 				errx(EXIT_FAILURE, "Invalid queue_size.");
608 			break;
609 		case 'R':
610 			if (action != CREATE && action != RESCUE)
611 				usage();
612 			errno = 0;
613 			rcvbuf = strtoul(optarg, NULL, 10);
614 			if (rcvbuf == 0 && errno != 0)
615 				errx(EXIT_FAILURE, "Invalid rcvbuf.");
616 			break;
617 		case 'S':
618 			if (action != CREATE && action != RESCUE)
619 				usage();
620 			errno = 0;
621 			sndbuf = strtoul(optarg, NULL, 10);
622 			if (sndbuf == 0 && errno != 0)
623 				errx(EXIT_FAILURE, "Invalid sndbuf.");
624 			break;
625 		case 's':
626 			if (action != CREATE)
627 				usage();
628 			errno = 0;
629 			sectorsize = strtoul(optarg, NULL, 10);
630 			if (sectorsize == 0 && errno != 0)
631 				errx(EXIT_FAILURE, "Invalid sectorsize.");
632 			break;
633 		case 't':
634 			if (action != CREATE)
635 				usage();
636 			errno = 0;
637 			timeout = strtoul(optarg, NULL, 10);
638 			if (timeout == 0 && errno != 0)
639 				errx(EXIT_FAILURE, "Invalid timeout.");
640 			break;
641 		case 'u':
642 			errno = 0;
643 			unit = strtol(optarg, NULL, 10);
644 			if (unit == 0 && errno != 0)
645 				errx(EXIT_FAILURE, "Invalid unit number.");
646 			break;
647 		case 'v':
648 			if (action == DESTROY)
649 				usage();
650 			g_gate_verbose++;
651 			break;
652 		default:
653 			usage();
654 		}
655 	}
656 	argc -= optind;
657 	argv += optind;
658 
659 	init_initial_buffer_size();
660 
661 	switch (action) {
662 	case CREATE:
663 		if (argc != 2)
664 			usage();
665 		g_gate_load_module();
666 		g_gate_open_device();
667 		host = argv[0];
668 		path = argv[1];
669 		g_gatec_create();
670 		break;
671 	case DESTROY:
672 		if (unit == -1) {
673 			fprintf(stderr, "Required unit number.\n");
674 			usage();
675 		}
676 		g_gate_verbose = 1;
677 		g_gate_open_device();
678 		g_gate_destroy(unit, force);
679 		break;
680 	case LIST:
681 		g_gate_list(unit, g_gate_verbose);
682 		break;
683 	case RESCUE:
684 		if (argc != 2)
685 			usage();
686 		if (unit == -1) {
687 			fprintf(stderr, "Required unit number.\n");
688 			usage();
689 		}
690 		g_gate_open_device();
691 		host = argv[0];
692 		path = argv[1];
693 		g_gatec_rescue();
694 		break;
695 	case UNSET:
696 	default:
697 		usage();
698 	}
699 	g_gate_close_device();
700 	exit(EXIT_SUCCESS);
701 }
702