xref: /openbsd-src/usr.bin/tmux/tmux.c (revision 9a53e128e82783ea59ef6d1323ae061f893b30e7)
1 /* $OpenBSD: tmux.c,v 1.69 2010/02/06 17:15:33 nicm Exp $ */
2 
3 /*
4  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
15  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
16  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 #include <sys/stat.h>
21 
22 #include <errno.h>
23 #include <event.h>
24 #include <paths.h>
25 #include <pwd.h>
26 #include <signal.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <syslog.h>
30 #include <unistd.h>
31 
32 #include "tmux.h"
33 
34 #ifdef DEBUG
35 extern char	*malloc_options;
36 #endif
37 
38 char		*cfg_file;
39 struct options	 global_options;	/* server options */
40 struct options	 global_s_options;	/* session options */
41 struct options	 global_w_options;	/* window options */
42 struct environ	 global_environ;
43 
44 int		 debug_level;
45 time_t		 start_time;
46 char		*socket_path;
47 int		 login_shell;
48 
49 __dead void	 usage(void);
50 void	 	 fill_session(struct msg_command_data *);
51 char 		*makesockpath(const char *);
52 __dead void	 shell_exec(const char *, const char *);
53 
54 struct imsgbuf	*main_ibuf;
55 struct event	 main_ev_sigterm;
56 int	         main_exitval;
57 
58 void		 main_set_signals(void);
59 void		 main_clear_signals(void);
60 void		 main_signal(int, short, unused void *);
61 void		 main_callback(int, short, void *);
62 void		 main_dispatch(const char *);
63 
64 __dead void
65 usage(void)
66 {
67 	fprintf(stderr,
68 	    "usage: %s [-28lquv] [-c shell-command] [-f file] [-L socket-name]\n"
69 	    "            [-S socket-path] [command [flags]]\n",
70 	    __progname);
71 	exit(1);
72 }
73 
74 void
75 logfile(const char *name)
76 {
77 	char	*path;
78 
79 	log_close();
80 	if (debug_level > 0) {
81 		xasprintf(&path, "tmux-%s-%ld.log", name, (long) getpid());
82 		log_open_file(debug_level, path);
83 		xfree(path);
84 	}
85 }
86 
87 const char *
88 getshell(void)
89 {
90 	struct passwd	*pw;
91 	const char	*shell;
92 
93 	shell = getenv("SHELL");
94 	if (checkshell(shell))
95 		return (shell);
96 
97 	pw = getpwuid(getuid());
98 	if (pw != NULL && checkshell(pw->pw_shell))
99 		return (pw->pw_shell);
100 
101 	return (_PATH_BSHELL);
102 }
103 
104 int
105 checkshell(const char *shell)
106 {
107 	if (shell == NULL || *shell == '\0' || areshell(shell))
108 		return (0);
109 	if (access(shell, X_OK) != 0)
110 		return (0);
111 	return (1);
112 }
113 
114 int
115 areshell(const char *shell)
116 {
117 	const char	*progname, *ptr;
118 
119 	if ((ptr = strrchr(shell, '/')) != NULL)
120 		ptr++;
121 	else
122 		ptr = shell;
123 	progname = __progname;
124 	if (*progname == '-')
125 		progname++;
126 	if (strcmp(ptr, progname) == 0)
127 		return (1);
128 	return (0);
129 }
130 
131 void
132 fill_session(struct msg_command_data *data)
133 {
134 	char		*env, *ptr1, *ptr2, buf[256];
135 	size_t		 len;
136 	const char	*errstr;
137 	long long	 ll;
138 
139 	data->pid = -1;
140 	if ((env = getenv("TMUX")) == NULL)
141 		return;
142 
143 	if ((ptr2 = strrchr(env, ',')) == NULL || ptr2 == env)
144 		return;
145 	for (ptr1 = ptr2 - 1; ptr1 > env && *ptr1 != ','; ptr1--)
146 		;
147 	if (*ptr1 != ',')
148 		return;
149 	ptr1++;
150 	ptr2++;
151 
152 	len = ptr2 - ptr1 - 1;
153 	if (len > (sizeof buf) - 1)
154 		return;
155 	memcpy(buf, ptr1, len);
156 	buf[len] = '\0';
157 
158 	ll = strtonum(buf, 0, LONG_MAX, &errstr);
159 	if (errstr != NULL)
160 		return;
161 	data->pid = ll;
162 
163 	ll = strtonum(ptr2, 0, UINT_MAX, &errstr);
164 	if (errstr != NULL)
165 		return;
166 	data->idx = ll;
167 }
168 
169 char *
170 makesockpath(const char *label)
171 {
172 	char		base[MAXPATHLEN], *path;
173 	struct stat	sb;
174 	u_int		uid;
175 
176 	uid = getuid();
177 	xsnprintf(base, MAXPATHLEN, "%s/tmux-%d", _PATH_TMP, uid);
178 
179 	if (mkdir(base, S_IRWXU) != 0 && errno != EEXIST)
180 		return (NULL);
181 
182 	if (lstat(base, &sb) != 0)
183 		return (NULL);
184 	if (!S_ISDIR(sb.st_mode)) {
185 		errno = ENOTDIR;
186 		return (NULL);
187 	}
188 	if (sb.st_uid != uid || (sb.st_mode & (S_IRWXG|S_IRWXO)) != 0) {
189 		errno = EACCES;
190 		return (NULL);
191 	}
192 
193 	xasprintf(&path, "%s/%s", base, label);
194 	return (path);
195 }
196 
197 __dead void
198 shell_exec(const char *shell, const char *shellcmd)
199 {
200 	const char	*shellname, *ptr;
201 	char		*argv0;
202 
203 	ptr = strrchr(shell, '/');
204 	if (ptr != NULL && *(ptr + 1) != '\0')
205 		shellname = ptr + 1;
206 	else
207 		shellname = shell;
208 	if (login_shell)
209 		xasprintf(&argv0, "-%s", shellname);
210 	else
211 		xasprintf(&argv0, "%s", shellname);
212 	setenv("SHELL", shell, 1);
213 
214 	execl(shell, argv0, "-c", shellcmd, (char *) NULL);
215 	fatal("execl failed");
216 }
217 
218 int
219 main(int argc, char **argv)
220 {
221 	struct cmd_list		*cmdlist;
222 	struct cmd		*cmd;
223 	enum msgtype		 msg;
224 	struct passwd		*pw;
225 	struct options		*oo, *so, *wo;
226 	struct keylist		*keylist;
227 	struct msg_command_data	 cmddata;
228 	char			*s, *shellcmd, *path, *label, *home, *cause;
229 	char			 cwd[MAXPATHLEN], **var;
230 	void			*buf;
231 	size_t			 len;
232 	int	 		 opt, flags, quiet = 0, cmdflags = 0;
233 	short		 	 events;
234 
235 #ifdef DEBUG
236 	malloc_options = (char *) "AFGJPX";
237 #endif
238 
239 	flags = 0;
240 	shellcmd = label = path = NULL;
241 	login_shell = (**argv == '-');
242 	while ((opt = getopt(argc, argv, "28c:df:lL:qS:uUv")) != -1) {
243 		switch (opt) {
244 		case '2':
245 			flags |= IDENTIFY_256COLOURS;
246 			flags &= ~IDENTIFY_88COLOURS;
247 			break;
248 		case '8':
249 			flags |= IDENTIFY_88COLOURS;
250 			flags &= ~IDENTIFY_256COLOURS;
251 			break;
252 		case 'c':
253 			if (shellcmd != NULL)
254 				xfree(shellcmd);
255 			shellcmd = xstrdup(optarg);
256 			break;
257 		case 'f':
258 			if (cfg_file != NULL)
259 				xfree(cfg_file);
260 			cfg_file = xstrdup(optarg);
261 			break;
262 		case 'l':
263 			login_shell = 1;
264 			break;
265 		case 'L':
266 			if (label != NULL)
267 				xfree(label);
268 			label = xstrdup(optarg);
269 			break;
270 		case 'q':
271 			quiet = 1;
272 			break;
273 		case 'S':
274 			if (path != NULL)
275 				xfree(path);
276 			path = xstrdup(optarg);
277 			break;
278 		case 'u':
279 			flags |= IDENTIFY_UTF8;
280 			break;
281 		case 'v':
282 			debug_level++;
283 			break;
284 		default:
285 			usage();
286 		}
287 	}
288 	argc -= optind;
289 	argv += optind;
290 
291 	if (shellcmd != NULL && argc != 0)
292 		usage();
293 
294 	log_open_tty(debug_level);
295 
296 	if (!(flags & IDENTIFY_UTF8)) {
297 		/*
298 		 * If the user has set whichever of LC_ALL, LC_CTYPE or LANG
299 		 * exist (in that order) to contain UTF-8, it is a safe
300 		 * assumption that either they are using a UTF-8 terminal, or
301 		 * if not they know that output from UTF-8-capable programs may
302 		 * be wrong.
303 		 */
304 		if ((s = getenv("LC_ALL")) == NULL) {
305 			if ((s = getenv("LC_CTYPE")) == NULL)
306 				s = getenv("LANG");
307 		}
308 		if (s != NULL && (strcasestr(s, "UTF-8") != NULL ||
309 		    strcasestr(s, "UTF8") != NULL))
310 			flags |= IDENTIFY_UTF8;
311 	}
312 
313 	environ_init(&global_environ);
314 	for (var = environ; *var != NULL; var++)
315 		environ_put(&global_environ, *var);
316 
317 	options_init(&global_options, NULL);
318 	oo = &global_options;
319 	options_set_number(oo, "quiet", quiet);
320 	options_set_number(oo, "escape-time", 500);
321 
322 	options_init(&global_s_options, NULL);
323 	so = &global_s_options;
324 	options_set_number(so, "base-index", 0);
325 	options_set_number(so, "bell-action", BELL_ANY);
326 	options_set_number(so, "buffer-limit", 9);
327 	options_set_string(so, "default-command", "%s", "");
328 	options_set_string(so, "default-shell", "%s", getshell());
329 	options_set_string(so, "default-terminal", "screen");
330 	options_set_number(so, "display-panes-colour", 4);
331 	options_set_number(so, "display-panes-active-colour", 1);
332 	options_set_number(so, "display-panes-time", 1000);
333 	options_set_number(so, "display-time", 750);
334 	options_set_number(so, "history-limit", 2000);
335 	options_set_number(so, "lock-after-time", 0);
336 	options_set_string(so, "lock-command", "lock -np");
337 	options_set_number(so, "lock-server", 1);
338 	options_set_number(so, "message-attr", 0);
339 	options_set_number(so, "message-bg", 3);
340 	options_set_number(so, "message-fg", 0);
341 	options_set_number(so, "message-limit", 20);
342 	options_set_number(so, "mouse-select-pane", 0);
343 	options_set_number(so, "pane-active-border-bg", 2);
344 	options_set_number(so, "pane-active-border-fg", 8);
345 	options_set_number(so, "pane-border-bg", 8);
346 	options_set_number(so, "pane-border-fg", 8);
347 	options_set_number(so, "repeat-time", 500);
348 	options_set_number(so, "set-remain-on-exit", 0);
349 	options_set_number(so, "set-titles", 0);
350 	options_set_string(so, "set-titles-string", "#S:#I:#W - \"#T\"");
351 	options_set_number(so, "status", 1);
352 	options_set_number(so, "status-attr", 0);
353 	options_set_number(so, "status-bg", 2);
354 	options_set_number(so, "status-fg", 0);
355 	options_set_number(so, "status-interval", 15);
356 	options_set_number(so, "status-justify", 0);
357 	options_set_number(so, "status-keys", MODEKEY_EMACS);
358 	options_set_string(so, "status-left", "[#S]");
359 	options_set_number(so, "status-left-attr", 0);
360 	options_set_number(so, "status-left-bg", 8);
361 	options_set_number(so, "status-left-fg", 8);
362 	options_set_number(so, "status-left-length", 10);
363 	options_set_string(so, "status-right", "\"#22T\" %%H:%%M %%d-%%b-%%y");
364 	options_set_number(so, "status-right-attr", 0);
365 	options_set_number(so, "status-right-bg", 8);
366 	options_set_number(so, "status-right-fg", 8);
367 	options_set_number(so, "status-right-length", 40);
368 	options_set_string(so, "terminal-overrides",
369 	    "*88col*:colors=88,*256col*:colors=256");
370 	options_set_string(so, "update-environment", "DISPLAY "
371 	    "WINDOWID SSH_ASKPASS SSH_AUTH_SOCK SSH_AGENT_PID SSH_CONNECTION");
372 	options_set_number(so, "visual-activity", 0);
373 	options_set_number(so, "visual-bell", 0);
374 	options_set_number(so, "visual-content", 0);
375 
376 	keylist = xmalloc(sizeof *keylist);
377 	ARRAY_INIT(keylist);
378 	ARRAY_ADD(keylist, '\002');
379 	options_set_data(so, "prefix", keylist, xfree);
380 
381 	options_init(&global_w_options, NULL);
382 	wo = &global_w_options;
383 	options_set_number(wo, "aggressive-resize", 0);
384 	options_set_number(wo, "automatic-rename", 1);
385 	options_set_number(wo, "clock-mode-colour", 4);
386 	options_set_number(wo, "clock-mode-style", 1);
387 	options_set_number(wo, "force-height", 0);
388 	options_set_number(wo, "force-width", 0);
389 	options_set_number(wo, "main-pane-height", 24);
390 	options_set_number(wo, "main-pane-width", 81);
391 	options_set_number(wo, "mode-attr", 0);
392 	options_set_number(wo, "mode-bg", 3);
393 	options_set_number(wo, "mode-fg", 0);
394 	options_set_number(wo, "mode-keys", MODEKEY_EMACS);
395 	options_set_number(wo, "mode-mouse", 0);
396 	options_set_number(wo, "monitor-activity", 0);
397 	options_set_string(wo, "monitor-content", "%s", "");
398 	options_set_number(wo, "window-status-attr", 0);
399 	options_set_number(wo, "window-status-bg", 8);
400 	options_set_number(wo, "window-status-current-attr", 0);
401 	options_set_number(wo, "window-status-current-bg", 8);
402 	options_set_number(wo, "window-status-current-fg", 8);
403 	options_set_number(wo, "window-status-fg", 8);
404 	options_set_string(wo, "window-status-format", "#I:#W#F");
405 	options_set_string(wo, "window-status-current-format", "#I:#W#F");
406 	options_set_number(wo, "xterm-keys", 0);
407 	options_set_number(wo, "remain-on-exit", 0);
408 	options_set_number(wo, "synchronize-panes", 0);
409 
410 	if (flags & IDENTIFY_UTF8) {
411 		options_set_number(so, "status-utf8", 1);
412 		options_set_number(wo, "utf8", 1);
413 	} else {
414 		options_set_number(so, "status-utf8", 0);
415 		options_set_number(wo, "utf8", 0);
416 	}
417 
418 	if (getcwd(cwd, sizeof cwd) == NULL) {
419 		pw = getpwuid(getuid());
420 		if (pw->pw_dir != NULL && *pw->pw_dir != '\0')
421 			strlcpy(cwd, pw->pw_dir, sizeof cwd);
422 		else
423 			strlcpy(cwd, "/", sizeof cwd);
424 	}
425 	options_set_string(so, "default-path", "%s", cwd);
426 
427 	if (cfg_file == NULL) {
428 		home = getenv("HOME");
429 		if (home == NULL || *home == '\0') {
430 			pw = getpwuid(getuid());
431 			if (pw != NULL)
432 				home = pw->pw_dir;
433 		}
434 		xasprintf(&cfg_file, "%s/%s", home, DEFAULT_CFG);
435 		if (access(cfg_file, R_OK) != 0 && errno == ENOENT) {
436 			xfree(cfg_file);
437 			cfg_file = NULL;
438 		}
439 	}
440 
441 	/*
442 	 * Figure out the socket path. If specified on the command-line with
443 	 * -S or -L, use it, otherwise try $TMUX or assume -L default.
444 	 */
445 	if (path == NULL) {
446 		/* No -L. Try $TMUX, or default. */
447 		if (label == NULL) {
448 			if ((path = getenv("TMUX")) != NULL) {
449 				path = xstrdup(path);
450 				path[strcspn(path, ",")] = '\0';
451 			} else
452 				label = xstrdup("default");
453 		}
454 
455 		/* -L or default set. */
456 		if (label != NULL) {
457 			if ((path = makesockpath(label)) == NULL) {
458 				log_warn("can't create socket");
459 				exit(1);
460 			}
461 		}
462 	}
463 	if (label != NULL)
464 		xfree(label);
465 
466 	if (shellcmd != NULL) {
467 		msg = MSG_SHELL;
468 		buf = NULL;
469 		len = 0;
470 	} else {
471 		fill_session(&cmddata);
472 
473 		cmddata.argc = argc;
474 		if (cmd_pack_argv(
475 		    argc, argv, cmddata.argv, sizeof cmddata.argv) != 0) {
476 			log_warnx("command too long");
477 			exit(1);
478 		}
479 
480 		msg = MSG_COMMAND;
481 		buf = &cmddata;
482 		len = sizeof cmddata;
483 	}
484 
485 	if (shellcmd != NULL)
486 		cmdflags |= CMD_STARTSERVER;
487 	else if (argc == 0)	/* new-session is the default */
488 		cmdflags |= CMD_STARTSERVER|CMD_SENDENVIRON;
489 	else {
490 		/*
491 		 * It sucks parsing the command string twice (in client and
492 		 * later in server) but it is necessary to get the start server
493 		 * flag.
494 		 */
495 		if ((cmdlist = cmd_list_parse(argc, argv, &cause)) == NULL) {
496 			log_warnx("%s", cause);
497 			exit(1);
498 		}
499 		cmdflags &= ~CMD_STARTSERVER;
500 		TAILQ_FOREACH(cmd, cmdlist, qentry) {
501 			if (cmd->entry->flags & CMD_STARTSERVER)
502 				cmdflags |= CMD_STARTSERVER;
503 			if (cmd->entry->flags & CMD_SENDENVIRON)
504 				cmdflags |= CMD_SENDENVIRON;
505 		}
506 		cmd_list_free(cmdlist);
507 	}
508 
509 	if ((main_ibuf = client_init(path, cmdflags, flags)) == NULL)
510 		exit(1);
511 	xfree(path);
512 
513 	event_init();
514 
515 	imsg_compose(main_ibuf, msg, PROTOCOL_VERSION, -1, -1, buf, len);
516 
517 	main_set_signals();
518 
519 	events = EV_READ;
520 	if (main_ibuf->w.queued > 0)
521 		events |= EV_WRITE;
522 	event_once(main_ibuf->fd, events, main_callback, shellcmd, NULL);
523 
524 	main_exitval = 0;
525 	event_dispatch();
526 
527 	main_clear_signals();
528 
529 	client_main();	/* doesn't return */
530 }
531 
532 void
533 main_set_signals(void)
534 {
535 	struct sigaction	sigact;
536 
537 	memset(&sigact, 0, sizeof sigact);
538 	sigemptyset(&sigact.sa_mask);
539 	sigact.sa_flags = SA_RESTART;
540 	sigact.sa_handler = SIG_IGN;
541 	if (sigaction(SIGINT, &sigact, NULL) != 0)
542 		fatal("sigaction failed");
543 	if (sigaction(SIGPIPE, &sigact, NULL) != 0)
544 		fatal("sigaction failed");
545 	if (sigaction(SIGUSR1, &sigact, NULL) != 0)
546 		fatal("sigaction failed");
547 	if (sigaction(SIGUSR2, &sigact, NULL) != 0)
548 		fatal("sigaction failed");
549 	if (sigaction(SIGTSTP, &sigact, NULL) != 0)
550 		fatal("sigaction failed");
551 
552 	signal_set(&main_ev_sigterm, SIGTERM, main_signal, NULL);
553 	signal_add(&main_ev_sigterm, NULL);
554 }
555 
556 void
557 main_clear_signals(void)
558 {
559 	struct sigaction	sigact;
560 
561 	memset(&sigact, 0, sizeof sigact);
562 	sigemptyset(&sigact.sa_mask);
563 	sigact.sa_flags = SA_RESTART;
564 	sigact.sa_handler = SIG_DFL;
565 	if (sigaction(SIGINT, &sigact, NULL) != 0)
566 		fatal("sigaction failed");
567 	if (sigaction(SIGPIPE, &sigact, NULL) != 0)
568 		fatal("sigaction failed");
569 	if (sigaction(SIGUSR1, &sigact, NULL) != 0)
570 		fatal("sigaction failed");
571 	if (sigaction(SIGUSR2, &sigact, NULL) != 0)
572 		fatal("sigaction failed");
573 	if (sigaction(SIGTSTP, &sigact, NULL) != 0)
574 		fatal("sigaction failed");
575 
576 	event_del(&main_ev_sigterm);
577 }
578 
579 /* ARGSUSED */
580 void
581 main_signal(int sig, unused short events, unused void *data)
582 {
583 	switch (sig) {
584 	case SIGTERM:
585 		exit(1);
586 	}
587 }
588 
589 /* ARGSUSED */
590 void
591 main_callback(unused int fd, short events, void *data)
592 {
593 	char	*shellcmd = data;
594 
595 	if (events & EV_READ)
596 		main_dispatch(shellcmd);
597 
598 	if (events & EV_WRITE) {
599 		if (msgbuf_write(&main_ibuf->w) < 0)
600 			fatalx("msgbuf_write failed");
601 	}
602 
603 	events = EV_READ;
604 	if (main_ibuf->w.queued > 0)
605 		events |= EV_WRITE;
606 	event_once(main_ibuf->fd, events, main_callback, shellcmd, NULL);
607 }
608 
609 void
610 main_dispatch(const char *shellcmd)
611 {
612 	struct imsg		imsg;
613 	ssize_t			n, datalen;
614 	struct msg_print_data	printdata;
615 	struct msg_shell_data	shelldata;
616 
617 	if ((n = imsg_read(main_ibuf)) == -1 || n == 0)
618 		fatalx("imsg_read failed");
619 
620 	for (;;) {
621 		if ((n = imsg_get(main_ibuf, &imsg)) == -1)
622 			fatalx("imsg_get failed");
623 		if (n == 0)
624 			return;
625 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
626 
627 		switch (imsg.hdr.type) {
628 		case MSG_EXIT:
629 		case MSG_SHUTDOWN:
630 			if (datalen != 0)
631 				fatalx("bad MSG_EXIT size");
632 
633 			exit(main_exitval);
634 		case MSG_ERROR:
635 		case MSG_PRINT:
636 			if (datalen != sizeof printdata)
637 				fatalx("bad MSG_PRINT size");
638 			memcpy(&printdata, imsg.data, sizeof printdata);
639 			printdata.msg[(sizeof printdata.msg) - 1] = '\0';
640 
641 			log_info("%s", printdata.msg);
642 			if (imsg.hdr.type == MSG_ERROR)
643 				main_exitval = 1;
644 			break;
645 		case MSG_READY:
646 			if (datalen != 0)
647 				fatalx("bad MSG_READY size");
648 
649 			event_loopexit(NULL);	/* move to client_main() */
650 			break;
651 		case MSG_VERSION:
652 			if (datalen != 0)
653 				fatalx("bad MSG_VERSION size");
654 
655 			log_warnx("protocol version mismatch (client %u, "
656 			    "server %u)", PROTOCOL_VERSION, imsg.hdr.peerid);
657 			exit(1);
658 		case MSG_SHELL:
659 			if (datalen != sizeof shelldata)
660 				fatalx("bad MSG_SHELL size");
661 			memcpy(&shelldata, imsg.data, sizeof shelldata);
662 			shelldata.shell[(sizeof shelldata.shell) - 1] = '\0';
663 
664 			main_clear_signals();
665 
666 			shell_exec(shelldata.shell, shellcmd);
667 		default:
668 			fatalx("unexpected message");
669 		}
670 
671 		imsg_free(&imsg);
672 	}
673 }
674