tmux.c revision 1.186 
1/* $OpenBSD: tmux.c,v 1.186 2018/01/12 10:22:02 nicm Exp $ */
2
3/*
4 * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
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 <err.h>
23#include <errno.h>
24#include <event.h>
25#include <fcntl.h>
26#include <langinfo.h>
27#include <locale.h>
28#include <paths.h>
29#include <pwd.h>
30#include <stdlib.h>
31#include <string.h>
32#include <time.h>
33#include <unistd.h>
34#include <util.h>
35
36#include "tmux.h"
37
38struct options	*global_options;	/* server options */
39struct options	*global_s_options;	/* session options */
40struct options	*global_w_options;	/* window options */
41struct environ	*global_environ;
42struct hooks	*global_hooks;
43
44struct timeval	 start_time;
45const char	*socket_path;
46int		 ptm_fd = -1;
47const char	*shell_command;
48
49static __dead void	 usage(void);
50static char		*make_label(const char *, char **);
51
52static const char	*getshell(void);
53static int		 checkshell(const char *);
54
55static __dead void
56usage(void)
57{
58	fprintf(stderr,
59	    "usage: %s [-2Cluv] [-c shell-command] [-f file] [-L socket-name]\n"
60	    "            [-S socket-path] [command [flags]]\n",
61	    getprogname());
62	exit(1);
63}
64
65static const char *
66getshell(void)
67{
68	struct passwd	*pw;
69	const char	*shell;
70
71	shell = getenv("SHELL");
72	if (checkshell(shell))
73		return (shell);
74
75	pw = getpwuid(getuid());
76	if (pw != NULL && checkshell(pw->pw_shell))
77		return (pw->pw_shell);
78
79	return (_PATH_BSHELL);
80}
81
82static int
83checkshell(const char *shell)
84{
85	if (shell == NULL || *shell != '/')
86		return (0);
87	if (areshell(shell))
88		return (0);
89	if (access(shell, X_OK) != 0)
90		return (0);
91	return (1);
92}
93
94int
95areshell(const char *shell)
96{
97	const char	*progname, *ptr;
98
99	if ((ptr = strrchr(shell, '/')) != NULL)
100		ptr++;
101	else
102		ptr = shell;
103	progname = getprogname();
104	if (*progname == '-')
105		progname++;
106	if (strcmp(ptr, progname) == 0)
107		return (1);
108	return (0);
109}
110
111static char *
112make_label(const char *label, char **cause)
113{
114	char		*base, resolved[PATH_MAX], *path, *s;
115	struct stat	 sb;
116	uid_t		 uid;
117
118	*cause = NULL;
119
120	if (label == NULL)
121		label = "default";
122	uid = getuid();
123
124	if ((s = getenv("TMUX_TMPDIR")) != NULL && *s != '\0')
125		xasprintf(&base, "%s/tmux-%ld", s, (long)uid);
126	else
127		xasprintf(&base, "%s/tmux-%ld", _PATH_TMP, (long)uid);
128	if (realpath(base, resolved) == NULL &&
129	    strlcpy(resolved, base, sizeof resolved) >= sizeof resolved) {
130		errno = ERANGE;
131		free(base);
132		goto fail;
133	}
134
135	if (mkdir(resolved, S_IRWXU) != 0 && errno != EEXIST)
136		goto fail;
137	if (lstat(resolved, &sb) != 0)
138		goto fail;
139	if (!S_ISDIR(sb.st_mode)) {
140		errno = ENOTDIR;
141		goto fail;
142	}
143	if (sb.st_uid != uid || (sb.st_mode & S_IRWXO) != 0) {
144		errno = EACCES;
145		goto fail;
146	}
147	xasprintf(&path, "%s/%s", resolved, label);
148	return (path);
149
150fail:
151	xasprintf(cause, "error creating %s (%s)", resolved, strerror(errno));
152	return (NULL);
153}
154
155void
156setblocking(int fd, int state)
157{
158	int mode;
159
160	if ((mode = fcntl(fd, F_GETFL)) != -1) {
161		if (!state)
162			mode |= O_NONBLOCK;
163		else
164			mode &= ~O_NONBLOCK;
165		fcntl(fd, F_SETFL, mode);
166	}
167}
168
169const char *
170find_home(void)
171{
172	struct passwd		*pw;
173	static const char	*home;
174
175	if (home != NULL)
176		return (home);
177
178	home = getenv("HOME");
179	if (home == NULL || *home == '\0') {
180		pw = getpwuid(getuid());
181		if (pw != NULL)
182			home = pw->pw_dir;
183		else
184			home = NULL;
185	}
186
187	return (home);
188}
189
190int
191main(int argc, char **argv)
192{
193	char					*path, *label, *cause, **var;
194	char					 tmp[PATH_MAX];
195	const char				*s, *shell, *cwd;
196	int					 opt, flags, keys;
197	const struct options_table_entry	*oe;
198
199	if (setlocale(LC_CTYPE, "en_US.UTF-8") == NULL &&
200	    setlocale(LC_CTYPE, "C.UTF-8") == NULL) {
201		if (setlocale(LC_CTYPE, "") == NULL)
202			errx(1, "invalid LC_ALL, LC_CTYPE or LANG");
203		s = nl_langinfo(CODESET);
204		if (strcasecmp(s, "UTF-8") != 0 && strcasecmp(s, "UTF8") != 0)
205			errx(1, "need UTF-8 locale (LC_CTYPE) but have %s", s);
206	}
207
208	setlocale(LC_TIME, "");
209	tzset();
210
211	if (**argv == '-')
212		flags = CLIENT_LOGIN;
213	else
214		flags = 0;
215
216	label = path = NULL;
217	while ((opt = getopt(argc, argv, "2c:Cdf:lL:qS:uUv")) != -1) {
218		switch (opt) {
219		case '2':
220			flags |= CLIENT_256COLOURS;
221			break;
222		case 'c':
223			shell_command = optarg;
224			break;
225		case 'C':
226			if (flags & CLIENT_CONTROL)
227				flags |= CLIENT_CONTROLCONTROL;
228			else
229				flags |= CLIENT_CONTROL;
230			break;
231		case 'f':
232			set_cfg_file(optarg);
233			break;
234		case 'l':
235			flags |= CLIENT_LOGIN;
236			break;
237		case 'L':
238			free(label);
239			label = xstrdup(optarg);
240			break;
241		case 'q':
242			break;
243		case 'S':
244			free(path);
245			path = xstrdup(optarg);
246			break;
247		case 'u':
248			flags |= CLIENT_UTF8;
249			break;
250		case 'v':
251			log_add_level();
252			break;
253		default:
254			usage();
255		}
256	}
257	argc -= optind;
258	argv += optind;
259
260	if (shell_command != NULL && argc != 0)
261		usage();
262
263	if ((ptm_fd = getptmfd()) == -1)
264		err(1, "getptmfd");
265	if (pledge("stdio rpath wpath cpath flock fattr unix getpw sendfd "
266	    "recvfd proc exec tty ps", NULL) != 0)
267		err(1, "pledge");
268
269	/*
270	 * tmux is a UTF-8 terminal, so if TMUX is set, assume UTF-8.
271	 * Otherwise, if the user has set LC_ALL, LC_CTYPE or LANG to contain
272	 * UTF-8, it is a safe assumption that either they are using a UTF-8
273	 * terminal, or if not they know that output from UTF-8-capable
274	 * programs may be wrong.
275	 */
276	if (getenv("TMUX") != NULL)
277		flags |= CLIENT_UTF8;
278	else {
279		s = getenv("LC_ALL");
280		if (s == NULL || *s == '\0')
281			s = getenv("LC_CTYPE");
282		if (s == NULL || *s == '\0')
283			s = getenv("LANG");
284		if (s == NULL || *s == '\0')
285			s = "";
286		if (strcasestr(s, "UTF-8") != NULL ||
287		    strcasestr(s, "UTF8") != NULL)
288			flags |= CLIENT_UTF8;
289	}
290
291	global_hooks = hooks_create(NULL);
292
293	global_environ = environ_create();
294	for (var = environ; *var != NULL; var++)
295		environ_put(global_environ, *var);
296	if ((cwd = getenv("PWD")) == NULL &&
297	    (cwd = getcwd(tmp, sizeof tmp)) != NULL)
298		environ_set(global_environ, "PWD", "%s", cwd);
299
300	global_options = options_create(NULL);
301	global_s_options = options_create(NULL);
302	global_w_options = options_create(NULL);
303	for (oe = options_table; oe->name != NULL; oe++) {
304		if (oe->scope == OPTIONS_TABLE_SERVER)
305			options_default(global_options, oe);
306		if (oe->scope == OPTIONS_TABLE_SESSION)
307			options_default(global_s_options, oe);
308		if (oe->scope == OPTIONS_TABLE_WINDOW)
309			options_default(global_w_options, oe);
310	}
311
312	/*
313	 * The default shell comes from SHELL or from the user's passwd entry
314	 * if available.
315	 */
316	shell = getshell();
317	options_set_string(global_s_options, "default-shell", 0, "%s", shell);
318
319	/* Override keys to vi if VISUAL or EDITOR are set. */
320	if ((s = getenv("VISUAL")) != NULL || (s = getenv("EDITOR")) != NULL) {
321		if (strrchr(s, '/') != NULL)
322			s = strrchr(s, '/') + 1;
323		if (strstr(s, "vi") != NULL)
324			keys = MODEKEY_VI;
325		else
326			keys = MODEKEY_EMACS;
327		options_set_number(global_s_options, "status-keys", keys);
328		options_set_number(global_w_options, "mode-keys", keys);
329	}
330
331	/*
332	 * If socket is specified on the command-line with -S or -L, it is
333	 * used. Otherwise, $TMUX is checked and if that fails "default" is
334	 * used.
335	 */
336	if (path == NULL && label == NULL) {
337		s = getenv("TMUX");
338		if (s != NULL && *s != '\0' && *s != ',') {
339			path = xstrdup(s);
340			path[strcspn(path, ",")] = '\0';
341		}
342	}
343	if (path == NULL && (path = make_label(label, &cause)) == NULL) {
344		if (cause != NULL) {
345			fprintf(stderr, "%s\n", cause);
346			free(cause);
347		}
348		exit(1);
349	}
350	socket_path = path;
351	free(label);
352
353	/* Pass control to the client. */
354	exit(client_main(event_init(), argc, argv, flags));
355}
356