Return to tmux.c CVS log

Up to [local] / src / usr.bin / tmux

Tidy up the terminal detection and feature code and add named sets of
terminal features, each of which are defined in one place and map to a
builtin set of terminfo(5) capabilities. Features can be specified based
on TERM with a new terminal-features option or with the -T flag when
running tmux. tmux will also detect a few common terminals from the DA
and DSR responses.

This is intended to make it easier to configure tmux's use of
terminfo(5) even in the presence of outdated ncurses(3) or terminfo(5)
databases or for features which do not yet have a terminfo(5) entry.
Instead of having to grok terminfo(5) capability names and what they
should be set to in the terminal-overrides option, the user can
hopefully just give tmux a feature name and let it do the right thing.

The terminal-overrides option remains both for backwards compatibility
and to allow tweaks of individual capabilities.

tmux already did much of this already, this makes it tidier and simpler
to configure.

/* $OpenBSD: tmux.c,v 1.198 2020/04/20 13:25:36 nicm Exp $ */

/*
 * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/utsname.h>

#include <err.h>
#include <errno.h>
#include <event.h>
#include <fcntl.h>
#include <langinfo.h>
#include <locale.h>
#include <paths.h>
#include <pwd.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <util.h>

#include "tmux.h"

struct options	*global_options;	/* server options */
struct options	*global_s_options;	/* session options */
struct options	*global_w_options;	/* window options */
struct environ	*global_environ;

struct timeval	 start_time;
const char	*socket_path;
int		 ptm_fd = -1;
const char	*shell_command;

static __dead void	 usage(void);
static char		*make_label(const char *, char **);

static int		 areshell(const char *);
static const char	*getshell(void);

static __dead void
usage(void)
{
	fprintf(stderr,
	    "usage: %s [-2CluvV] [-c shell-command] [-f file] [-L socket-name]\n"
	    "            [-S socket-path] [-T features] [command [flags]]\n",
	    getprogname());
	exit(1);
}

static const char *
getshell(void)
{
	struct passwd	*pw;
	const char	*shell;

	shell = getenv("SHELL");
	if (checkshell(shell))
		return (shell);

	pw = getpwuid(getuid());
	if (pw != NULL && checkshell(pw->pw_shell))
		return (pw->pw_shell);

	return (_PATH_BSHELL);
}

int
checkshell(const char *shell)
{
	if (shell == NULL || *shell != '/')
		return (0);
	if (areshell(shell))
		return (0);
	if (access(shell, X_OK) != 0)
		return (0);
	return (1);
}

static int
areshell(const char *shell)
{
	const char	*progname, *ptr;

	if ((ptr = strrchr(shell, '/')) != NULL)
		ptr++;
	else
		ptr = shell;
	progname = getprogname();
	if (*progname == '-')
		progname++;
	if (strcmp(ptr, progname) == 0)
		return (1);
	return (0);
}

static char *
make_label(const char *label, char **cause)
{
	char		*base, resolved[PATH_MAX], *path, *s;
	struct stat	 sb;
	uid_t		 uid;

	*cause = NULL;

	if (label == NULL)
		label = "default";
	uid = getuid();

	if ((s = getenv("TMUX_TMPDIR")) != NULL && *s != '\0')
		xasprintf(&base, "%s/tmux-%ld", s, (long)uid);
	else
		xasprintf(&base, "%s/tmux-%ld", _PATH_TMP, (long)uid);
	if (realpath(base, resolved) == NULL &&
	    strlcpy(resolved, base, sizeof resolved) >= sizeof resolved) {
		errno = ERANGE;
		free(base);
		goto fail;
	}
	free(base);

	if (mkdir(resolved, S_IRWXU) != 0 && errno != EEXIST)
		goto fail;
	if (lstat(resolved, &sb) != 0)
		goto fail;
	if (!S_ISDIR(sb.st_mode)) {
		errno = ENOTDIR;
		goto fail;
	}
	if (sb.st_uid != uid || (sb.st_mode & S_IRWXO) != 0) {
		errno = EACCES;
		goto fail;
	}
	xasprintf(&path, "%s/%s", resolved, label);
	return (path);

fail:
	xasprintf(cause, "error creating %s (%s)", resolved, strerror(errno));
	return (NULL);
}

void
setblocking(int fd, int state)
{
	int mode;

	if ((mode = fcntl(fd, F_GETFL)) != -1) {
		if (!state)
			mode |= O_NONBLOCK;
		else
			mode &= ~O_NONBLOCK;
		fcntl(fd, F_SETFL, mode);
	}
}

const char *
sig2name(int signo)
{
     static char	s[11];

     if (signo > 0 && signo < NSIG)
	     return (sys_signame[signo]);
     xsnprintf(s, sizeof s, "%d", signo);
     return (s);
}

const char *
find_cwd(void)
{
	char		 resolved1[PATH_MAX], resolved2[PATH_MAX];
	static char	 cwd[PATH_MAX];
	const char	*pwd;

	if (getcwd(cwd, sizeof cwd) == NULL)
		return (NULL);
	if ((pwd = getenv("PWD")) == NULL || *pwd == '\0')
		return (cwd);

	/*
	 * We want to use PWD so that symbolic links are maintained,
	 * but only if it matches the actual working directory.
	 */
	if (realpath(pwd, resolved1) == NULL)
		return (cwd);
	if (realpath(cwd, resolved2) == NULL)
		return (cwd);
	if (strcmp(resolved1, resolved2) != 0)
		return (cwd);
	return (pwd);
}

const char *
find_home(void)
{
	struct passwd		*pw;
	static const char	*home;

	if (home != NULL)
		return (home);

	home = getenv("HOME");
	if (home == NULL || *home == '\0') {
		pw = getpwuid(getuid());
		if (pw != NULL)
			home = pw->pw_dir;
		else
			home = NULL;
	}

	return (home);
}

const char *
getversion(void)
{
	static char	*version;
	struct utsname	 u;

	if (version == NULL) {
		if (uname(&u) < 0)
			fatalx("uname failed");
		xasprintf(&version, "openbsd-%s", u.release);
	}
	return (version);
}

int
main(int argc, char **argv)
{
	char					*path = NULL, *label = NULL;
	char					*cause, **var;
	const char				*s, *shell, *cwd;
	int					 opt, flags = 0, keys;
	int					 feat = 0;
	const struct options_table_entry	*oe;

	if (setlocale(LC_CTYPE, "en_US.UTF-8") == NULL &&
	    setlocale(LC_CTYPE, "C.UTF-8") == NULL) {
		if (setlocale(LC_CTYPE, "") == NULL)
			errx(1, "invalid LC_ALL, LC_CTYPE or LANG");
		s = nl_langinfo(CODESET);
		if (strcasecmp(s, "UTF-8") != 0 && strcasecmp(s, "UTF8") != 0)
			errx(1, "need UTF-8 locale (LC_CTYPE) but have %s", s);
	}

	setlocale(LC_TIME, "");
	tzset();

	if (**argv == '-')
		flags = CLIENT_LOGIN;

	while ((opt = getopt(argc, argv, "2c:Cdf:lL:qS:T:uUvV")) != -1) {
		switch (opt) {
		case '2':
			tty_add_features(&feat, "256", ":,");
			break;
		case 'c':
			shell_command = optarg;
			break;
		case 'C':
			if (flags & CLIENT_CONTROL)
				flags |= CLIENT_CONTROLCONTROL;
			else
				flags |= CLIENT_CONTROL;
			break;
		case 'f':
			set_cfg_file(optarg);
			break;
 		case 'V':
			printf("%s %s\n", getprogname(), getversion());
 			exit(0);
		case 'l':
			flags |= CLIENT_LOGIN;
			break;
		case 'L':
			free(label);
			label = xstrdup(optarg);
			break;
		case 'q':
			break;
		case 'S':
			free(path);
			path = xstrdup(optarg);
			break;
		case 'T':
			tty_add_features(&feat, optarg, ":,");
			break;
		case 'u':
			flags |= CLIENT_UTF8;
			break;
		case 'v':
			log_add_level();
			break;
		default:
			usage();
		}
	}
	argc -= optind;
	argv += optind;

	if (shell_command != NULL && argc != 0)
		usage();

	if ((ptm_fd = getptmfd()) == -1)
		err(1, "getptmfd");
	if (pledge("stdio rpath wpath cpath flock fattr unix getpw sendfd "
	    "recvfd proc exec tty ps", NULL) != 0)
		err(1, "pledge");

	/*
	 * tmux is a UTF-8 terminal, so if TMUX is set, assume UTF-8.
	 * Otherwise, if the user has set LC_ALL, LC_CTYPE or LANG to contain
	 * UTF-8, it is a safe assumption that either they are using a UTF-8
	 * terminal, or if not they know that output from UTF-8-capable
	 * programs may be wrong.
	 */
	if (getenv("TMUX") != NULL)
		flags |= CLIENT_UTF8;
	else {
		s = getenv("LC_ALL");
		if (s == NULL || *s == '\0')
			s = getenv("LC_CTYPE");
		if (s == NULL || *s == '\0')
			s = getenv("LANG");
		if (s == NULL || *s == '\0')
			s = "";
		if (strcasestr(s, "UTF-8") != NULL ||
		    strcasestr(s, "UTF8") != NULL)
			flags |= CLIENT_UTF8;
	}

	global_environ = environ_create();
	for (var = environ; *var != NULL; var++)
		environ_put(global_environ, *var, 0);
	if ((cwd = find_cwd()) != NULL)
		environ_set(global_environ, "PWD", 0, "%s", cwd);

	global_options = options_create(NULL);
	global_s_options = options_create(NULL);
	global_w_options = options_create(NULL);
	for (oe = options_table; oe->name != NULL; oe++) {
		if (oe->scope & OPTIONS_TABLE_SERVER)
			options_default(global_options, oe);
		if (oe->scope & OPTIONS_TABLE_SESSION)
			options_default(global_s_options, oe);
		if (oe->scope & OPTIONS_TABLE_WINDOW)
			options_default(global_w_options, oe);
	}

	/*
	 * The default shell comes from SHELL or from the user's passwd entry
	 * if available.
	 */
	shell = getshell();
	options_set_string(global_s_options, "default-shell", 0, "%s", shell);

	/* Override keys to vi if VISUAL or EDITOR are set. */
	if ((s = getenv("VISUAL")) != NULL || (s = getenv("EDITOR")) != NULL) {
		if (strrchr(s, '/') != NULL)
			s = strrchr(s, '/') + 1;
		if (strstr(s, "vi") != NULL)
			keys = MODEKEY_VI;
		else
			keys = MODEKEY_EMACS;
		options_set_number(global_s_options, "status-keys", keys);
		options_set_number(global_w_options, "mode-keys", keys);
	}

	/*
	 * If socket is specified on the command-line with -S or -L, it is
	 * used. Otherwise, $TMUX is checked and if that fails "default" is
	 * used.
	 */
	if (path == NULL && label == NULL) {
		s = getenv("TMUX");
		if (s != NULL && *s != '\0' && *s != ',') {
			path = xstrdup(s);
			path[strcspn(path, ",")] = '\0';
		}
	}
	if (path == NULL) {
		if ((path = make_label(label, &cause)) == NULL) {
			if (cause != NULL) {
				fprintf(stderr, "%s\n", cause);
				free(cause);
			}
			exit(1);
		}
		flags |= CLIENT_DEFAULTSOCKET;
	}
	socket_path = path;
	free(label);

	/* Pass control to the client. */
	exit(client_main(event_init(), argc, argv, flags, feat));
}