tmux.c revision 1.106 
1/* $OpenBSD: tmux.c,v 1.106 2011/10/23 08:03:27 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 <fcntl.h>
25#include <paths.h>
26#include <pwd.h>
27#include <stdlib.h>
28#include <string.h>
29#include <unistd.h>
30
31#include "tmux.h"
32
33#ifdef DEBUG
34extern char	*malloc_options;
35#endif
36
37struct options	 global_options;	/* server options */
38struct options	 global_s_options;	/* session options */
39struct options	 global_w_options;	/* window options */
40struct environ	 global_environ;
41
42struct event_base *ev_base;
43
44char		*cfg_file;
45char		*shell_cmd;
46int		 debug_level;
47time_t		 start_time;
48char		 socket_path[MAXPATHLEN];
49int		 login_shell;
50char		*environ_path;
51pid_t		 environ_pid = -1;
52int		 environ_idx = -1;
53
54__dead void	 usage(void);
55void	 	 parseenvironment(void);
56char 		*makesocketpath(const char *);
57
58__dead void
59usage(void)
60{
61	fprintf(stderr,
62	    "usage: %s [-28lquv] [-c shell-command] [-f file] [-L socket-name]\n"
63	    "            [-S socket-path] [command [flags]]\n",
64	    __progname);
65	exit(1);
66}
67
68void
69logfile(const char *name)
70{
71	char	*path;
72
73	log_close();
74	if (debug_level > 0) {
75		xasprintf(&path, "tmux-%s-%ld.log", name, (long) getpid());
76		log_open_file(debug_level, path);
77		xfree(path);
78	}
79}
80
81const char *
82getshell(void)
83{
84	struct passwd	*pw;
85	const char	*shell;
86
87	shell = getenv("SHELL");
88	if (checkshell(shell))
89		return (shell);
90
91	pw = getpwuid(getuid());
92	if (pw != NULL && checkshell(pw->pw_shell))
93		return (pw->pw_shell);
94
95	return (_PATH_BSHELL);
96}
97
98int
99checkshell(const char *shell)
100{
101	if (shell == NULL || *shell == '\0' || *shell != '/')
102		return (0);
103	if (areshell(shell))
104		return (0);
105	if (access(shell, X_OK) != 0)
106		return (0);
107	return (1);
108}
109
110int
111areshell(const char *shell)
112{
113	const char	*progname, *ptr;
114
115	if ((ptr = strrchr(shell, '/')) != NULL)
116		ptr++;
117	else
118		ptr = shell;
119	progname = __progname;
120	if (*progname == '-')
121		progname++;
122	if (strcmp(ptr, progname) == 0)
123		return (1);
124	return (0);
125}
126
127void
128parseenvironment(void)
129{
130	char	*env, path[256];
131	long	 pid;
132	int	 idx;
133
134	if ((env = getenv("TMUX")) == NULL)
135		return;
136
137	if (sscanf(env, "%255[^,],%ld,%d", path, &pid, &idx) != 3)
138		return;
139	environ_path = xstrdup(path);
140	environ_pid = pid;
141	environ_idx = idx;
142}
143
144char *
145makesocketpath(const char *label)
146{
147	char		base[MAXPATHLEN], *path, *s;
148	struct stat	sb;
149	u_int		uid;
150
151	uid = getuid();
152	if ((s = getenv("TMPDIR")) == NULL || *s == '\0')
153		xsnprintf(base, sizeof base, "%s/tmux-%u", _PATH_TMP, uid);
154	else
155		xsnprintf(base, sizeof base, "%s/tmux-%u", s, uid);
156
157	if (mkdir(base, S_IRWXU) != 0 && errno != EEXIST)
158		return (NULL);
159
160	if (lstat(base, &sb) != 0)
161		return (NULL);
162	if (!S_ISDIR(sb.st_mode)) {
163		errno = ENOTDIR;
164		return (NULL);
165	}
166	if (sb.st_uid != uid || (sb.st_mode & (S_IRWXG|S_IRWXO)) != 0) {
167		errno = EACCES;
168		return (NULL);
169	}
170
171	xasprintf(&path, "%s/%s", base, label);
172	return (path);
173}
174
175void
176setblocking(int fd, int state)
177{
178	int mode;
179
180	if ((mode = fcntl(fd, F_GETFL)) != -1) {
181		if (!state)
182			mode |= O_NONBLOCK;
183		else
184			mode &= ~O_NONBLOCK;
185		fcntl(fd, F_SETFL, mode);
186	}
187}
188
189__dead void
190shell_exec(const char *shell, const char *shellcmd)
191{
192	const char	*shellname, *ptr;
193	char		*argv0;
194
195	ptr = strrchr(shell, '/');
196	if (ptr != NULL && *(ptr + 1) != '\0')
197		shellname = ptr + 1;
198	else
199		shellname = shell;
200	if (login_shell)
201		xasprintf(&argv0, "-%s", shellname);
202	else
203		xasprintf(&argv0, "%s", shellname);
204	setenv("SHELL", shell, 1);
205
206	setblocking(STDIN_FILENO, 1);
207	setblocking(STDOUT_FILENO, 1);
208	setblocking(STDERR_FILENO, 1);
209	closefrom(STDERR_FILENO + 1);
210
211	execl(shell, argv0, "-c", shellcmd, (char *) NULL);
212	fatal("execl failed");
213}
214
215int
216main(int argc, char **argv)
217{
218	struct passwd	*pw;
219	struct keylist	*keylist;
220	char		*s, *path, *label, *home, **var;
221	int	 	 opt, flags, quiet, keys;
222
223#ifdef DEBUG
224	malloc_options = (char *) "AFGJPX";
225#endif
226
227	quiet = flags = 0;
228	label = path = NULL;
229	login_shell = (**argv == '-');
230	while ((opt = getopt(argc, argv, "28c:df:lL:qS:uUv")) != -1) {
231		switch (opt) {
232		case '2':
233			flags |= IDENTIFY_256COLOURS;
234			flags &= ~IDENTIFY_88COLOURS;
235			break;
236		case '8':
237			flags |= IDENTIFY_88COLOURS;
238			flags &= ~IDENTIFY_256COLOURS;
239			break;
240		case 'c':
241			if (shell_cmd != NULL)
242				xfree(shell_cmd);
243			shell_cmd = xstrdup(optarg);
244			break;
245		case 'f':
246			if (cfg_file != NULL)
247				xfree(cfg_file);
248			cfg_file = xstrdup(optarg);
249			break;
250		case 'l':
251			login_shell = 1;
252			break;
253		case 'L':
254			if (label != NULL)
255				xfree(label);
256			label = xstrdup(optarg);
257			break;
258		case 'q':
259			quiet = 1;
260			break;
261		case 'S':
262			if (path != NULL)
263				xfree(path);
264			path = xstrdup(optarg);
265			break;
266		case 'u':
267			flags |= IDENTIFY_UTF8;
268			break;
269		case 'v':
270			debug_level++;
271			break;
272		default:
273			usage();
274		}
275	}
276	argc -= optind;
277	argv += optind;
278
279	if (shell_cmd != NULL && argc != 0)
280		usage();
281
282	log_open_tty(debug_level);
283
284	if (!(flags & IDENTIFY_UTF8)) {
285		/*
286		 * If the user has set whichever of LC_ALL, LC_CTYPE or LANG
287		 * exist (in that order) to contain UTF-8, it is a safe
288		 * assumption that either they are using a UTF-8 terminal, or
289		 * if not they know that output from UTF-8-capable programs may
290		 * be wrong.
291		 */
292		if ((s = getenv("LC_ALL")) == NULL || *s == '\0') {
293			if ((s = getenv("LC_CTYPE")) == NULL || *s == '\0')
294				s = getenv("LANG");
295		}
296		if (s != NULL && (strcasestr(s, "UTF-8") != NULL ||
297		    strcasestr(s, "UTF8") != NULL))
298			flags |= IDENTIFY_UTF8;
299	}
300
301	environ_init(&global_environ);
302	for (var = environ; *var != NULL; var++)
303		environ_put(&global_environ, *var);
304
305	options_init(&global_options, NULL);
306	options_table_populate_tree(server_options_table, &global_options);
307	options_set_number(&global_options, "quiet", quiet);
308
309	options_init(&global_s_options, NULL);
310	options_table_populate_tree(session_options_table, &global_s_options);
311	options_set_string(&global_s_options, "default-shell", "%s", getshell());
312
313	options_init(&global_w_options, NULL);
314	options_table_populate_tree(window_options_table, &global_w_options);
315
316	/* Set the prefix option (its a list, so not in the table). */
317	keylist = xmalloc(sizeof *keylist);
318	ARRAY_INIT(keylist);
319	ARRAY_ADD(keylist, '\002');
320	options_set_data(&global_s_options, "prefix", keylist, xfree);
321
322	/* Enable UTF-8 if the first client is on UTF-8 terminal. */
323	if (flags & IDENTIFY_UTF8) {
324		options_set_number(&global_s_options, "status-utf8", 1);
325		options_set_number(&global_s_options, "mouse-utf8", 1);
326		options_set_number(&global_w_options, "utf8", 1);
327	}
328
329	/* Override keys to vi if VISUAL or EDITOR are set. */
330	if ((s = getenv("VISUAL")) != NULL || (s = getenv("EDITOR")) != NULL) {
331		if (strrchr(s, '/') != NULL)
332			s = strrchr(s, '/') + 1;
333		if (strstr(s, "vi") != NULL)
334			keys = MODEKEY_VI;
335		else
336			keys = MODEKEY_EMACS;
337		options_set_number(&global_s_options, "status-keys", keys);
338		options_set_number(&global_w_options, "mode-keys", keys);
339	}
340
341	/* Locate the configuration file. */
342	if (cfg_file == NULL) {
343		home = getenv("HOME");
344		if (home == NULL || *home == '\0') {
345			pw = getpwuid(getuid());
346			if (pw != NULL)
347				home = pw->pw_dir;
348		}
349		xasprintf(&cfg_file, "%s/%s", home, DEFAULT_CFG);
350		if (access(cfg_file, R_OK) != 0 && errno == ENOENT) {
351			xfree(cfg_file);
352			cfg_file = NULL;
353		}
354	}
355
356	/*
357	 * Figure out the socket path. If specified on the command-line with -S
358	 * or -L, use it, otherwise try $TMUX or assume -L default.
359	 */
360	parseenvironment();
361	if (path == NULL) {
362		/* If no -L, use the environment. */
363		if (label == NULL) {
364			if (environ_path != NULL)
365				path = xstrdup(environ_path);
366			else
367				label = xstrdup("default");
368		}
369
370		/* -L or default set. */
371		if (label != NULL) {
372			if ((path = makesocketpath(label)) == NULL) {
373				log_warn("can't create socket");
374				exit(1);
375			}
376		}
377	}
378	if (label != NULL)
379		xfree(label);
380	if (realpath(path, socket_path) == NULL)
381		strlcpy(socket_path, path, sizeof socket_path);
382	xfree(path);
383
384	/* Set process title. */
385	setproctitle("%s (%s)", __progname, socket_path);
386
387	/* Pass control to the client. */
388	ev_base = event_init();
389	exit(client_main(argc, argv, flags));
390}
391