tmux.c revision 1.177 
1/* $OpenBSD: tmux.c,v 1.177 2017/02/16 10:53:25 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 <getopt.h>
27#include <langinfo.h>
28#include <locale.h>
29#include <paths.h>
30#include <pwd.h>
31#include <stdlib.h>
32#include <string.h>
33#include <time.h>
34#include <unistd.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;
47
48static __dead void	 usage(void);
49static char		*make_label(const char *);
50
51static const char	*getshell(void);
52static int		 checkshell(const char *);
53
54static __dead void
55usage(void)
56{
57	fprintf(stderr,
58	    "usage: %s [-2Cluv] [-c shell-command] [-f file] [-L socket-name]\n"
59	    "            [-S socket-path] [command [flags]]\n",
60	    getprogname());
61	exit(1);
62}
63
64static const char *
65getshell(void)
66{
67	struct passwd	*pw;
68	const char	*shell;
69
70	shell = getenv("SHELL");
71	if (checkshell(shell))
72		return (shell);
73
74	pw = getpwuid(getuid());
75	if (pw != NULL && checkshell(pw->pw_shell))
76		return (pw->pw_shell);
77
78	return (_PATH_BSHELL);
79}
80
81static int
82checkshell(const char *shell)
83{
84	if (shell == NULL || *shell != '/')
85		return (0);
86	if (areshell(shell))
87		return (0);
88	if (access(shell, X_OK) != 0)
89		return (0);
90	return (1);
91}
92
93int
94areshell(const char *shell)
95{
96	const char	*progname, *ptr;
97
98	if ((ptr = strrchr(shell, '/')) != NULL)
99		ptr++;
100	else
101		ptr = shell;
102	progname = getprogname();
103	if (*progname == '-')
104		progname++;
105	if (strcmp(ptr, progname) == 0)
106		return (1);
107	return (0);
108}
109
110static char *
111make_label(const char *label)
112{
113	char		*base, resolved[PATH_MAX], *path, *s;
114	struct stat	 sb;
115	u_int		 uid;
116	int		 saved_errno;
117
118	if (label == NULL)
119		label = "default";
120
121	uid = getuid();
122
123	if ((s = getenv("TMUX_TMPDIR")) != NULL && *s != '\0')
124		xasprintf(&base, "%s/tmux-%u", s, uid);
125	else
126		xasprintf(&base, "%s/tmux-%u", _PATH_TMP, uid);
127
128	if (mkdir(base, S_IRWXU) != 0 && errno != EEXIST)
129		goto fail;
130
131	if (lstat(base, &sb) != 0)
132		goto fail;
133	if (!S_ISDIR(sb.st_mode)) {
134		errno = ENOTDIR;
135		goto fail;
136	}
137	if (sb.st_uid != uid || (sb.st_mode & S_IRWXO) != 0) {
138		errno = EACCES;
139		goto fail;
140	}
141
142	if (realpath(base, resolved) == NULL)
143		strlcpy(resolved, base, sizeof resolved);
144	xasprintf(&path, "%s/%s", resolved, label);
145	return (path);
146
147fail:
148	saved_errno = errno;
149	free(base);
150	errno = saved_errno;
151	return (NULL);
152}
153
154void
155setblocking(int fd, int state)
156{
157	int mode;
158
159	if ((mode = fcntl(fd, F_GETFL)) != -1) {
160		if (!state)
161			mode |= O_NONBLOCK;
162		else
163			mode &= ~O_NONBLOCK;
164		fcntl(fd, F_SETFL, mode);
165	}
166}
167
168const char *
169find_home(void)
170{
171	struct passwd		*pw;
172	static const char	*home;
173
174	if (home != NULL)
175		return (home);
176
177	home = getenv("HOME");
178	if (home == NULL || *home == '\0') {
179		pw = getpwuid(getuid());
180		if (pw != NULL)
181			home = pw->pw_dir;
182		else
183			home = NULL;
184	}
185
186	return (home);
187}
188
189int
190main(int argc, char **argv)
191{
192	char					*path, *label, tmp[PATH_MAX];
193	char					*shellcmd = NULL, **var;
194	const char				*s, *shell;
195	int					 opt, flags, keys;
196	const struct options_table_entry	*oe;
197
198	if (setlocale(LC_CTYPE, "en_US.UTF-8") == NULL) {
199		if (setlocale(LC_CTYPE, "") == NULL)
200			errx(1, "invalid LC_ALL, LC_CTYPE or LANG");
201		s = nl_langinfo(CODESET);
202		if (strcasecmp(s, "UTF-8") != 0 && strcasecmp(s, "UTF8") != 0)
203			errx(1, "need UTF-8 locale (LC_CTYPE) but have %s", s);
204	}
205
206	setlocale(LC_TIME, "");
207	tzset();
208
209	if (**argv == '-')
210		flags = CLIENT_LOGIN;
211	else
212		flags = 0;
213
214	label = path = NULL;
215	while ((opt = getopt(argc, argv, "2c:Cdf:lL:qS:uUv")) != -1) {
216		switch (opt) {
217		case '2':
218			flags |= CLIENT_256COLOURS;
219			break;
220		case 'c':
221			free(shellcmd);
222			shellcmd = xstrdup(optarg);
223			break;
224		case 'C':
225			if (flags & CLIENT_CONTROL)
226				flags |= CLIENT_CONTROLCONTROL;
227			else
228				flags |= CLIENT_CONTROL;
229			break;
230		case 'f':
231			set_cfg_file(optarg);
232			break;
233		case 'l':
234			flags |= CLIENT_LOGIN;
235			break;
236		case 'L':
237			free(label);
238			label = xstrdup(optarg);
239			break;
240		case 'q':
241			break;
242		case 'S':
243			free(path);
244			path = xstrdup(optarg);
245			break;
246		case 'u':
247			flags |= CLIENT_UTF8;
248			break;
249		case 'v':
250			log_add_level();
251			break;
252		default:
253			usage();
254		}
255	}
256	argc -= optind;
257	argv += optind;
258
259	if (shellcmd != NULL && argc != 0)
260		usage();
261
262	if (pty_open(&ptm_fd) != 0)
263		errx(1, "open(\"/dev/ptm\"");
264	if (pledge("stdio rpath wpath cpath flock fattr unix getpw sendfd "
265	    "recvfd proc exec tty ps", NULL) != 0)
266		err(1, "pledge");
267
268	/*
269	 * tmux is a UTF-8 terminal, so if TMUX is set, assume UTF-8.
270	 * Otherwise, if the user has set LC_ALL, LC_CTYPE or LANG to contain
271	 * UTF-8, it is a safe assumption that either they are using a UTF-8
272	 * terminal, or if not they know that output from UTF-8-capable
273	 * programs may be wrong.
274	 */
275	if (getenv("TMUX") != NULL)
276		flags |= CLIENT_UTF8;
277	else {
278		s = getenv("LC_ALL");
279		if (s == NULL || *s == '\0')
280			s = getenv("LC_CTYPE");
281		if (s == NULL || *s == '\0')
282			s = getenv("LANG");
283		if (s == NULL || *s == '\0')
284			s = "";
285		if (strcasestr(s, "UTF-8") != NULL ||
286		    strcasestr(s, "UTF8") != NULL)
287			flags |= CLIENT_UTF8;
288	}
289
290	global_hooks = hooks_create(NULL);
291
292	global_environ = environ_create();
293	for (var = environ; *var != NULL; var++)
294		environ_put(global_environ, *var);
295	if (getcwd(tmp, sizeof tmp) != NULL)
296		environ_set(global_environ, "PWD", "%s", tmp);
297
298	global_options = options_create(NULL);
299	global_s_options = options_create(NULL);
300	global_w_options = options_create(NULL);
301	for (oe = options_table; oe->name != NULL; oe++) {
302		if (oe->scope == OPTIONS_TABLE_SERVER)
303			options_default(global_options, oe);
304		if (oe->scope == OPTIONS_TABLE_SESSION)
305			options_default(global_s_options, oe);
306		if (oe->scope == OPTIONS_TABLE_WINDOW)
307			options_default(global_w_options, oe);
308	}
309
310	/*
311	 * The default shell comes from SHELL or from the user's passwd entry
312	 * if available.
313	 */
314	shell = getshell();
315	options_set_string(global_s_options, "default-shell", 0, "%s", shell);
316
317	/* Override keys to vi if VISUAL or EDITOR are set. */
318	if ((s = getenv("VISUAL")) != NULL || (s = getenv("EDITOR")) != NULL) {
319		if (strrchr(s, '/') != NULL)
320			s = strrchr(s, '/') + 1;
321		if (strstr(s, "vi") != NULL)
322			keys = MODEKEY_VI;
323		else
324			keys = MODEKEY_EMACS;
325		options_set_number(global_s_options, "status-keys", keys);
326		options_set_number(global_w_options, "mode-keys", keys);
327	}
328
329	/*
330	 * If socket is specified on the command-line with -S or -L, it is
331	 * used. Otherwise, $TMUX is checked and if that fails "default" is
332	 * used.
333	 */
334	if (path == NULL && label == NULL) {
335		s = getenv("TMUX");
336		if (s != NULL && *s != '\0' && *s != ',') {
337			path = xstrdup(s);
338			path[strcspn(path, ",")] = '\0';
339		}
340	}
341	if (path == NULL && (path = make_label(label)) == NULL) {
342		fprintf(stderr, "can't create socket: %s\n", strerror(errno));
343		exit(1);
344	}
345	socket_path = path;
346	free(label);
347
348	/* Pass control to the client. */
349	exit(client_main(event_init(), argc, argv, flags, shellcmd));
350}
351