tmux.c revision 1.104 
1/* $OpenBSD: tmux.c,v 1.104 2011/03/04 23:26:44 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' || areshell(shell))
102		return (0);
103	if (access(shell, X_OK) != 0)
104		return (0);
105	return (1);
106}
107
108int
109areshell(const char *shell)
110{
111	const char	*progname, *ptr;
112
113	if ((ptr = strrchr(shell, '/')) != NULL)
114		ptr++;
115	else
116		ptr = shell;
117	progname = __progname;
118	if (*progname == '-')
119		progname++;
120	if (strcmp(ptr, progname) == 0)
121		return (1);
122	return (0);
123}
124
125void
126parseenvironment(void)
127{
128	char	*env, path[256];
129	long	 pid;
130	int	 idx;
131
132	if ((env = getenv("TMUX")) == NULL)
133		return;
134
135	if (sscanf(env, "%255[^,],%ld,%d", path, &pid, &idx) != 3)
136		return;
137	environ_path = xstrdup(path);
138	environ_pid = pid;
139	environ_idx = idx;
140}
141
142char *
143makesocketpath(const char *label)
144{
145	char		base[MAXPATHLEN], *path, *s;
146	struct stat	sb;
147	u_int		uid;
148
149	uid = getuid();
150	if ((s = getenv("TMPDIR")) == NULL || *s == '\0')
151		xsnprintf(base, sizeof base, "%s/tmux-%u", _PATH_TMP, uid);
152	else
153		xsnprintf(base, sizeof base, "%s/tmux-%u", s, uid);
154
155	if (mkdir(base, S_IRWXU) != 0 && errno != EEXIST)
156		return (NULL);
157
158	if (lstat(base, &sb) != 0)
159		return (NULL);
160	if (!S_ISDIR(sb.st_mode)) {
161		errno = ENOTDIR;
162		return (NULL);
163	}
164	if (sb.st_uid != uid || (sb.st_mode & (S_IRWXG|S_IRWXO)) != 0) {
165		errno = EACCES;
166		return (NULL);
167	}
168
169	xasprintf(&path, "%s/%s", base, label);
170	return (path);
171}
172
173void
174setblocking(int fd, int state)
175{
176	int mode;
177
178	if ((mode = fcntl(fd, F_GETFL)) != -1) {
179		if (!state)
180			mode |= O_NONBLOCK;
181		else
182			mode &= ~O_NONBLOCK;
183		fcntl(fd, F_SETFL, mode);
184	}
185}
186
187__dead void
188shell_exec(const char *shell, const char *shellcmd)
189{
190	const char	*shellname, *ptr;
191	char		*argv0;
192
193	ptr = strrchr(shell, '/');
194	if (ptr != NULL && *(ptr + 1) != '\0')
195		shellname = ptr + 1;
196	else
197		shellname = shell;
198	if (login_shell)
199		xasprintf(&argv0, "-%s", shellname);
200	else
201		xasprintf(&argv0, "%s", shellname);
202	setenv("SHELL", shell, 1);
203
204	setblocking(STDIN_FILENO, 1);
205	setblocking(STDOUT_FILENO, 1);
206	setblocking(STDERR_FILENO, 1);
207	closefrom(STDERR_FILENO + 1);
208
209	execl(shell, argv0, "-c", shellcmd, (char *) NULL);
210	fatal("execl failed");
211}
212
213int
214main(int argc, char **argv)
215{
216	struct passwd	*pw;
217	struct keylist	*keylist;
218	char		*s, *path, *label, *home, **var;
219	int	 	 opt, flags, quiet, keys;
220
221#ifdef DEBUG
222	malloc_options = (char *) "AFGJPX";
223#endif
224
225	quiet = flags = 0;
226	label = path = NULL;
227	login_shell = (**argv == '-');
228	while ((opt = getopt(argc, argv, "28c:df:lL:qS:uUv")) != -1) {
229		switch (opt) {
230		case '2':
231			flags |= IDENTIFY_256COLOURS;
232			flags &= ~IDENTIFY_88COLOURS;
233			break;
234		case '8':
235			flags |= IDENTIFY_88COLOURS;
236			flags &= ~IDENTIFY_256COLOURS;
237			break;
238		case 'c':
239			if (shell_cmd != NULL)
240				xfree(shell_cmd);
241			shell_cmd = xstrdup(optarg);
242			break;
243		case 'f':
244			if (cfg_file != NULL)
245				xfree(cfg_file);
246			cfg_file = xstrdup(optarg);
247			break;
248		case 'l':
249			login_shell = 1;
250			break;
251		case 'L':
252			if (label != NULL)
253				xfree(label);
254			label = xstrdup(optarg);
255			break;
256		case 'q':
257			quiet = 1;
258			break;
259		case 'S':
260			if (path != NULL)
261				xfree(path);
262			path = xstrdup(optarg);
263			break;
264		case 'u':
265			flags |= IDENTIFY_UTF8;
266			break;
267		case 'v':
268			debug_level++;
269			break;
270		default:
271			usage();
272		}
273	}
274	argc -= optind;
275	argv += optind;
276
277	if (shell_cmd != NULL && argc != 0)
278		usage();
279
280	log_open_tty(debug_level);
281
282	if (!(flags & IDENTIFY_UTF8)) {
283		/*
284		 * If the user has set whichever of LC_ALL, LC_CTYPE or LANG
285		 * exist (in that order) to contain UTF-8, it is a safe
286		 * assumption that either they are using a UTF-8 terminal, or
287		 * if not they know that output from UTF-8-capable programs may
288		 * be wrong.
289		 */
290		if ((s = getenv("LC_ALL")) == NULL) {
291			if ((s = getenv("LC_CTYPE")) == NULL)
292				s = getenv("LANG");
293		}
294		if (s != NULL && (strcasestr(s, "UTF-8") != NULL ||
295		    strcasestr(s, "UTF8") != NULL))
296			flags |= IDENTIFY_UTF8;
297	}
298
299	environ_init(&global_environ);
300	for (var = environ; *var != NULL; var++)
301		environ_put(&global_environ, *var);
302
303	options_init(&global_options, NULL);
304	options_table_populate_tree(server_options_table, &global_options);
305	options_set_number(&global_options, "quiet", quiet);
306
307	options_init(&global_s_options, NULL);
308	options_table_populate_tree(session_options_table, &global_s_options);
309	options_set_string(&global_s_options, "default-shell", "%s", getshell());
310
311	options_init(&global_w_options, NULL);
312	options_table_populate_tree(window_options_table, &global_w_options);
313
314	/* Set the prefix option (its a list, so not in the table). */
315	keylist = xmalloc(sizeof *keylist);
316	ARRAY_INIT(keylist);
317	ARRAY_ADD(keylist, '\002');
318	options_set_data(&global_s_options, "prefix", keylist, xfree);
319
320	/* Enable UTF-8 if the first client is on UTF-8 terminal. */
321	if (flags & IDENTIFY_UTF8) {
322		options_set_number(&global_s_options, "status-utf8", 1);
323		options_set_number(&global_s_options, "mouse-utf8", 1);
324		options_set_number(&global_w_options, "utf8", 1);
325	}
326
327	/* Override keys to vi if VISUAL or EDITOR are set. */
328	if ((s = getenv("VISUAL")) != NULL || (s = getenv("EDITOR")) != NULL) {
329		if (strrchr(s, '/') != NULL)
330			s = strrchr(s, '/') + 1;
331		if (strstr(s, "vi") != NULL)
332			keys = MODEKEY_VI;
333		else
334			keys = MODEKEY_EMACS;
335		options_set_number(&global_s_options, "status-keys", keys);
336		options_set_number(&global_w_options, "mode-keys", keys);
337	}
338
339	/* Locate the configuration file. */
340	if (cfg_file == NULL) {
341		home = getenv("HOME");
342		if (home == NULL || *home == '\0') {
343			pw = getpwuid(getuid());
344			if (pw != NULL)
345				home = pw->pw_dir;
346		}
347		xasprintf(&cfg_file, "%s/%s", home, DEFAULT_CFG);
348		if (access(cfg_file, R_OK) != 0 && errno == ENOENT) {
349			xfree(cfg_file);
350			cfg_file = NULL;
351		}
352	}
353
354	/*
355	 * Figure out the socket path. If specified on the command-line with -S
356	 * or -L, use it, otherwise try $TMUX or assume -L default.
357	 */
358	parseenvironment();
359	if (path == NULL) {
360		/* If no -L, use the environment. */
361		if (label == NULL) {
362			if (environ_path != NULL)
363				path = xstrdup(environ_path);
364			else
365				label = xstrdup("default");
366		}
367
368		/* -L or default set. */
369		if (label != NULL) {
370			if ((path = makesocketpath(label)) == NULL) {
371				log_warn("can't create socket");
372				exit(1);
373			}
374		}
375	}
376	if (label != NULL)
377		xfree(label);
378	if (realpath(path, socket_path) == NULL)
379		strlcpy(socket_path, path, sizeof socket_path);
380	xfree(path);
381
382	/* Set process title. */
383	setproctitle("%s (%s)", __progname, socket_path);
384
385	/* Pass control to the client. */
386	ev_base = event_init();
387	exit(client_main(argc, argv, flags));
388}
389