tmux/tmux.c
Tiago Cunha 7163907ab6 Sync OpenBSD patchset 684:
Catch SIGCHLD to avoid a zombie, from patrick keshishian.
2010-04-22 21:48:49 +00:00

731 lines
18 KiB
C

/* $Id: tmux.c,v 1.205 2010-04-22 21:48:49 tcunha Exp $ */
/*
* Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
*
* 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 <errno.h>
#include <event.h>
#include <pwd.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include "tmux.h"
#if defined(DEBUG) && defined(__OpenBSD__)
extern char *malloc_options;
#endif
char *cfg_file;
struct options global_options; /* server options */
struct options global_s_options; /* session options */
struct options global_w_options; /* window options */
struct environ global_environ;
int debug_level;
time_t start_time;
char *socket_path;
int login_shell;
struct env_data {
char *path;
pid_t pid;
u_int idx;
};
__dead void usage(void);
void parse_env(struct env_data *);
char *makesockpath(const char *);
__dead void shell_exec(const char *, const char *);
struct imsgbuf *main_ibuf;
struct event main_ev_sigterm;
int main_exitval;
void main_set_signals(void);
void main_clear_signals(void);
void main_signal(int, short, unused void *);
void main_callback(int, short, void *);
void main_dispatch(const char *);
#ifndef HAVE_PROGNAME
char *__progname = (char *) "tmux";
#endif
__dead void
usage(void)
{
fprintf(stderr,
"usage: %s [-28lquv] [-c shell-command] [-f file] [-L socket-name]\n"
" [-S socket-path] [command [flags]]\n",
__progname);
exit(1);
}
void
logfile(const char *name)
{
char *path;
log_close();
if (debug_level > 0) {
xasprintf(&path, "tmux-%s-%ld.log", name, (long) getpid());
log_open_file(debug_level, path);
xfree(path);
}
}
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 == '\0' || areshell(shell))
return (0);
if (access(shell, X_OK) != 0)
return (0);
return (1);
}
int
areshell(const char *shell)
{
const char *progname, *ptr;
if ((ptr = strrchr(shell, '/')) != NULL)
ptr++;
else
ptr = shell;
progname = __progname;
if (*progname == '-')
progname++;
if (strcmp(ptr, progname) == 0)
return (1);
return (0);
}
void
parse_env(struct env_data *data)
{
char *env, *path_pid, *pid_idx, buf[256];
size_t len;
const char *errstr;
long long ll;
data->pid = -1;
if ((env = getenv("TMUX")) == NULL)
return;
if ((path_pid = strchr(env, ',')) == NULL || path_pid == env)
return;
if ((pid_idx = strchr(path_pid + 1, ',')) == NULL)
return;
if ((pid_idx == path_pid + 1 || pid_idx[1] == '\0'))
return;
/* path */
len = path_pid - env;
data->path = xmalloc (len + 1);
memcpy(data->path, env, len);
data->path[len] = '\0';
/* pid */
len = pid_idx - path_pid - 1;
if (len > (sizeof buf) - 1)
return;
memcpy(buf, path_pid + 1, len);
buf[len] = '\0';
ll = strtonum(buf, 0, LONG_MAX, &errstr);
if (errstr != NULL)
return;
data->pid = ll;
/* idx */
ll = strtonum(pid_idx+1, 0, UINT_MAX, &errstr);
if (errstr != NULL)
return;
data->idx = ll;
}
char *
makesockpath(const char *label)
{
char base[MAXPATHLEN], *path;
struct stat sb;
u_int uid;
uid = getuid();
xsnprintf(base, MAXPATHLEN, "%s/tmux-%d", _PATH_TMP, uid);
if (mkdir(base, S_IRWXU) != 0 && errno != EEXIST)
return (NULL);
if (lstat(base, &sb) != 0)
return (NULL);
if (!S_ISDIR(sb.st_mode)) {
errno = ENOTDIR;
return (NULL);
}
if (sb.st_uid != uid || (sb.st_mode & (S_IRWXG|S_IRWXO)) != 0) {
errno = EACCES;
return (NULL);
}
xasprintf(&path, "%s/%s", base, label);
return (path);
}
__dead void
shell_exec(const char *shell, const char *shellcmd)
{
const char *shellname, *ptr;
char *argv0;
ptr = strrchr(shell, '/');
if (ptr != NULL && *(ptr + 1) != '\0')
shellname = ptr + 1;
else
shellname = shell;
if (login_shell)
xasprintf(&argv0, "-%s", shellname);
else
xasprintf(&argv0, "%s", shellname);
setenv("SHELL", shell, 1);
execl(shell, argv0, "-c", shellcmd, (char *) NULL);
fatal("execl failed");
}
int
main(int argc, char **argv)
{
struct cmd_list *cmdlist;
struct cmd *cmd;
enum msgtype msg;
struct passwd *pw;
struct options *oo, *so, *wo;
struct keylist *keylist;
struct env_data envdata;
struct msg_command_data cmddata;
struct sigaction sigact;
char *s, *shellcmd, *path, *label, *home, *cause;
char cwd[MAXPATHLEN], **var;
void *buf;
size_t len;
int opt, flags, quiet = 0, cmdflags = 0;
short events;
#if defined(DEBUG) && defined(__OpenBSD__)
malloc_options = (char *) "AFGJPX";
#endif
flags = 0;
shellcmd = label = path = NULL;
envdata.path = NULL;
login_shell = (**argv == '-');
while ((opt = getopt(argc, argv, "28c:df:lL:qS:uUv")) != -1) {
switch (opt) {
case '2':
flags |= IDENTIFY_256COLOURS;
flags &= ~IDENTIFY_88COLOURS;
break;
case '8':
flags |= IDENTIFY_88COLOURS;
flags &= ~IDENTIFY_256COLOURS;
break;
case 'c':
if (shellcmd != NULL)
xfree(shellcmd);
shellcmd = xstrdup(optarg);
break;
case 'f':
if (cfg_file != NULL)
xfree(cfg_file);
cfg_file = xstrdup(optarg);
break;
case 'l':
login_shell = 1;
break;
case 'L':
if (label != NULL)
xfree(label);
label = xstrdup(optarg);
break;
case 'q':
quiet = 1;
break;
case 'S':
if (path != NULL)
xfree(path);
path = xstrdup(optarg);
break;
case 'u':
flags |= IDENTIFY_UTF8;
break;
case 'v':
debug_level++;
break;
default:
usage();
}
}
argc -= optind;
argv += optind;
if (shellcmd != NULL && argc != 0)
usage();
log_open_tty(debug_level);
if (!(flags & IDENTIFY_UTF8)) {
/*
* If the user has set whichever of LC_ALL, LC_CTYPE or LANG
* exist (in that order) 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 ((s = getenv("LC_ALL")) == NULL) {
if ((s = getenv("LC_CTYPE")) == NULL)
s = getenv("LANG");
}
if (s != NULL && (strcasestr(s, "UTF-8") != NULL ||
strcasestr(s, "UTF8") != NULL))
flags |= IDENTIFY_UTF8;
}
environ_init(&global_environ);
for (var = environ; *var != NULL; var++)
environ_put(&global_environ, *var);
options_init(&global_options, NULL);
oo = &global_options;
options_set_number(oo, "quiet", quiet);
options_set_number(oo, "escape-time", 500);
options_init(&global_s_options, NULL);
so = &global_s_options;
options_set_number(so, "base-index", 0);
options_set_number(so, "bell-action", BELL_ANY);
options_set_number(so, "buffer-limit", 9);
options_set_string(so, "default-command", "%s", "");
options_set_string(so, "default-shell", "%s", getshell());
options_set_string(so, "default-terminal", "screen");
options_set_number(so, "display-panes-colour", 4);
options_set_number(so, "display-panes-active-colour", 1);
options_set_number(so, "display-panes-time", 1000);
options_set_number(so, "display-time", 750);
options_set_number(so, "history-limit", 2000);
options_set_number(so, "lock-after-time", 0);
options_set_string(so, "lock-command", "lock -np");
options_set_number(so, "lock-server", 1);
options_set_number(so, "message-attr", 0);
options_set_number(so, "message-bg", 3);
options_set_number(so, "message-fg", 0);
options_set_number(so, "message-limit", 20);
options_set_number(so, "mouse-select-pane", 0);
options_set_number(so, "pane-active-border-bg", 2);
options_set_number(so, "pane-active-border-fg", 8);
options_set_number(so, "pane-border-bg", 8);
options_set_number(so, "pane-border-fg", 8);
options_set_number(so, "repeat-time", 500);
options_set_number(so, "set-remain-on-exit", 0);
options_set_number(so, "set-titles", 0);
options_set_string(so, "set-titles-string", "#S:#I:#W - \"#T\"");
options_set_number(so, "status", 1);
options_set_number(so, "status-attr", 0);
options_set_number(so, "status-bg", 2);
options_set_number(so, "status-fg", 0);
options_set_number(so, "status-interval", 15);
options_set_number(so, "status-justify", 0);
options_set_number(so, "status-keys", MODEKEY_EMACS);
options_set_string(so, "status-left", "[#S]");
options_set_number(so, "status-left-attr", 0);
options_set_number(so, "status-left-bg", 8);
options_set_number(so, "status-left-fg", 8);
options_set_number(so, "status-left-length", 10);
options_set_string(so, "status-right", "\"#22T\" %%H:%%M %%d-%%b-%%y");
options_set_number(so, "status-right-attr", 0);
options_set_number(so, "status-right-bg", 8);
options_set_number(so, "status-right-fg", 8);
options_set_number(so, "status-right-length", 40);
options_set_string(so, "terminal-overrides",
"*88col*:colors=88,*256col*:colors=256");
options_set_string(so, "update-environment", "DISPLAY "
"WINDOWID SSH_ASKPASS SSH_AUTH_SOCK SSH_AGENT_PID SSH_CONNECTION");
options_set_number(so, "visual-activity", 0);
options_set_number(so, "visual-bell", 0);
options_set_number(so, "visual-content", 0);
keylist = xmalloc(sizeof *keylist);
ARRAY_INIT(keylist);
ARRAY_ADD(keylist, '\002');
options_set_data(so, "prefix", keylist, xfree);
options_init(&global_w_options, NULL);
wo = &global_w_options;
options_set_number(wo, "aggressive-resize", 0);
options_set_number(wo, "alternate-screen", 1);
options_set_number(wo, "automatic-rename", 1);
options_set_number(wo, "clock-mode-colour", 4);
options_set_number(wo, "clock-mode-style", 1);
options_set_number(wo, "force-height", 0);
options_set_number(wo, "force-width", 0);
options_set_number(wo, "main-pane-height", 24);
options_set_number(wo, "main-pane-width", 81);
options_set_number(wo, "mode-attr", 0);
options_set_number(wo, "mode-bg", 3);
options_set_number(wo, "mode-fg", 0);
options_set_number(wo, "mode-keys", MODEKEY_EMACS);
options_set_number(wo, "mode-mouse", 0);
options_set_number(wo, "monitor-activity", 0);
options_set_string(wo, "monitor-content", "%s", "");
options_set_number(wo, "window-status-attr", 0);
options_set_number(wo, "window-status-bg", 8);
options_set_number(wo, "window-status-current-attr", 0);
options_set_number(wo, "window-status-current-bg", 8);
options_set_number(wo, "window-status-current-fg", 8);
options_set_number(wo, "window-status-fg", 8);
options_set_string(wo, "window-status-format", "#I:#W#F");
options_set_string(wo, "window-status-current-format", "#I:#W#F");
options_set_string(wo, "word-separators", " -_@");
options_set_number(wo, "xterm-keys", 0);
options_set_number(wo, "remain-on-exit", 0);
options_set_number(wo, "synchronize-panes", 0);
if (flags & IDENTIFY_UTF8) {
options_set_number(so, "status-utf8", 1);
options_set_number(wo, "utf8", 1);
} else {
options_set_number(so, "status-utf8", 0);
options_set_number(wo, "utf8", 0);
}
if (getcwd(cwd, sizeof cwd) == NULL) {
pw = getpwuid(getuid());
if (pw->pw_dir != NULL && *pw->pw_dir != '\0')
strlcpy(cwd, pw->pw_dir, sizeof cwd);
else
strlcpy(cwd, "/", sizeof cwd);
}
options_set_string(so, "default-path", "%s", cwd);
if (cfg_file == NULL) {
home = getenv("HOME");
if (home == NULL || *home == '\0') {
pw = getpwuid(getuid());
if (pw != NULL)
home = pw->pw_dir;
}
xasprintf(&cfg_file, "%s/%s", home, DEFAULT_CFG);
if (access(cfg_file, R_OK) != 0 && errno == ENOENT) {
xfree(cfg_file);
cfg_file = NULL;
}
}
/*
* Figure out the socket path. If specified on the command-line with
* -S or -L, use it, otherwise try $TMUX or assume -L default.
*/
parse_env(&envdata);
if (path == NULL) {
/* No -L. Try $TMUX, or default. */
if (label == NULL) {
path = envdata.path;
if (path == NULL)
label = xstrdup("default");
}
/* -L or default set. */
if (label != NULL) {
if ((path = makesockpath(label)) == NULL) {
log_warn("can't create socket");
exit(1);
}
}
}
if (label != NULL)
xfree(label);
if (shellcmd != NULL) {
msg = MSG_SHELL;
buf = NULL;
len = 0;
} else {
cmddata.pid = envdata.pid;
cmddata.idx = envdata.idx;
/* Prepare command for server. */
cmddata.argc = argc;
if (cmd_pack_argv(
argc, argv, cmddata.argv, sizeof cmddata.argv) != 0) {
log_warnx("command too long");
exit(1);
}
msg = MSG_COMMAND;
buf = &cmddata;
len = sizeof cmddata;
}
if (shellcmd != NULL)
cmdflags |= CMD_STARTSERVER;
else if (argc == 0) /* new-session is the default */
cmdflags |= CMD_STARTSERVER|CMD_SENDENVIRON|CMD_CANTNEST;
else {
/*
* It sucks parsing the command string twice (in client and
* later in server) but it is necessary to get the start server
* flag.
*/
if ((cmdlist = cmd_list_parse(argc, argv, &cause)) == NULL) {
log_warnx("%s", cause);
exit(1);
}
cmdflags &= ~CMD_STARTSERVER;
TAILQ_FOREACH(cmd, cmdlist, qentry) {
if (cmd->entry->flags & CMD_STARTSERVER)
cmdflags |= CMD_STARTSERVER;
if (cmd->entry->flags & CMD_SENDENVIRON)
cmdflags |= CMD_SENDENVIRON;
if (cmd->entry->flags & CMD_CANTNEST)
cmdflags |= CMD_CANTNEST;
}
cmd_list_free(cmdlist);
}
/*
* Check if this could be a nested session, if the command can't nest:
* if the socket path matches $TMUX, this is probably the same server.
*/
if (shellcmd == NULL && envdata.path != NULL &&
cmdflags & CMD_CANTNEST &&
(path == envdata.path || strcmp(path, envdata.path) == 0)) {
log_warnx("sessions should be nested with care. "
"unset $TMUX to force.");
exit(1);
}
/* Catch SIGCHLD to avoid a zombie when starting the server. */
memset(&sigact, 0, sizeof sigact);
sigemptyset(&sigact.sa_mask);
sigact.sa_handler = SIG_IGN;
if (sigaction(SIGCHLD, &sigact, NULL) != 0)
fatal("sigaction failed");
/* Initialise the client socket/start the server. */
if ((main_ibuf = client_init(path, cmdflags, flags)) == NULL)
exit(1);
xfree(path);
#ifdef HAVE_BROKEN_KQUEUE
if (setenv("EVENT_NOKQUEUE", "1", 1) != 0)
fatal("setenv failed");
#endif
#ifdef HAVE_BROKEN_POLL
if (setenv("EVENT_NOPOLL", "1", 1) != 0)
fatal("setenv failed");
#endif
event_init();
#ifdef HAVE_BROKEN_KQUEUE
unsetenv("EVENT_NOKQUEUE");
#endif
#ifdef HAVE_BROKEN_POLL
unsetenv("EVENT_NOPOLL");
#endif
imsg_compose(main_ibuf, msg, PROTOCOL_VERSION, -1, -1, buf, len);
main_set_signals();
events = EV_READ;
if (main_ibuf->w.queued > 0)
events |= EV_WRITE;
event_once(main_ibuf->fd, events, main_callback, shellcmd, NULL);
main_exitval = 0;
event_dispatch();
main_clear_signals();
client_main(); /* doesn't return */
}
void
main_set_signals(void)
{
struct sigaction sigact;
memset(&sigact, 0, sizeof sigact);
sigemptyset(&sigact.sa_mask);
sigact.sa_flags = SA_RESTART;
sigact.sa_handler = SIG_IGN;
if (sigaction(SIGINT, &sigact, NULL) != 0)
fatal("sigaction failed");
if (sigaction(SIGPIPE, &sigact, NULL) != 0)
fatal("sigaction failed");
if (sigaction(SIGUSR1, &sigact, NULL) != 0)
fatal("sigaction failed");
if (sigaction(SIGUSR2, &sigact, NULL) != 0)
fatal("sigaction failed");
if (sigaction(SIGTSTP, &sigact, NULL) != 0)
fatal("sigaction failed");
signal_set(&main_ev_sigterm, SIGTERM, main_signal, NULL);
signal_add(&main_ev_sigterm, NULL);
}
void
main_clear_signals(void)
{
struct sigaction sigact;
memset(&sigact, 0, sizeof sigact);
sigemptyset(&sigact.sa_mask);
sigact.sa_flags = SA_RESTART;
sigact.sa_handler = SIG_DFL;
if (sigaction(SIGINT, &sigact, NULL) != 0)
fatal("sigaction failed");
if (sigaction(SIGPIPE, &sigact, NULL) != 0)
fatal("sigaction failed");
if (sigaction(SIGUSR1, &sigact, NULL) != 0)
fatal("sigaction failed");
if (sigaction(SIGUSR2, &sigact, NULL) != 0)
fatal("sigaction failed");
if (sigaction(SIGTSTP, &sigact, NULL) != 0)
fatal("sigaction failed");
event_del(&main_ev_sigterm);
}
/* ARGSUSED */
void
main_signal(int sig, unused short events, unused void *data)
{
switch (sig) {
case SIGTERM:
exit(1);
}
}
/* ARGSUSED */
void
main_callback(unused int fd, short events, void *data)
{
char *shellcmd = data;
if (events & EV_READ)
main_dispatch(shellcmd);
if (events & EV_WRITE) {
if (msgbuf_write(&main_ibuf->w) < 0)
fatalx("msgbuf_write failed");
}
events = EV_READ;
if (main_ibuf->w.queued > 0)
events |= EV_WRITE;
event_once(main_ibuf->fd, events, main_callback, shellcmd, NULL);
}
void
main_dispatch(const char *shellcmd)
{
struct imsg imsg;
ssize_t n, datalen;
struct msg_print_data printdata;
struct msg_shell_data shelldata;
if ((n = imsg_read(main_ibuf)) == -1 || n == 0)
fatalx("imsg_read failed");
for (;;) {
if ((n = imsg_get(main_ibuf, &imsg)) == -1)
fatalx("imsg_get failed");
if (n == 0)
return;
datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
switch (imsg.hdr.type) {
case MSG_EXIT:
case MSG_SHUTDOWN:
if (datalen != 0)
fatalx("bad MSG_EXIT size");
exit(main_exitval);
case MSG_ERROR:
case MSG_PRINT:
if (datalen != sizeof printdata)
fatalx("bad MSG_PRINT size");
memcpy(&printdata, imsg.data, sizeof printdata);
printdata.msg[(sizeof printdata.msg) - 1] = '\0';
log_info("%s", printdata.msg);
if (imsg.hdr.type == MSG_ERROR)
main_exitval = 1;
break;
case MSG_READY:
if (datalen != 0)
fatalx("bad MSG_READY size");
event_loopexit(NULL); /* move to client_main() */
break;
case MSG_VERSION:
if (datalen != 0)
fatalx("bad MSG_VERSION size");
log_warnx("protocol version mismatch (client %u, "
"server %u)", PROTOCOL_VERSION, imsg.hdr.peerid);
exit(1);
case MSG_SHELL:
if (datalen != sizeof shelldata)
fatalx("bad MSG_SHELL size");
memcpy(&shelldata, imsg.data, sizeof shelldata);
shelldata.shell[(sizeof shelldata.shell) - 1] = '\0';
main_clear_signals();
shell_exec(shelldata.shell, shellcmd);
default:
fatalx("unexpected message");
}
imsg_free(&imsg);
}
}