Annotation of src/usr.bin/tmux/server.c, Revision 1.192
1.192 ! nicm 1: /* $OpenBSD: server.c,v 1.191 2020/05/16 16:07:55 nicm Exp $ */
1.1 nicm 2:
3: /*
1.157 nicm 4: * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
1.1 nicm 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/ioctl.h>
21: #include <sys/socket.h>
22: #include <sys/stat.h>
23: #include <sys/un.h>
24: #include <sys/wait.h>
25:
26: #include <errno.h>
1.66 nicm 27: #include <event.h>
1.1 nicm 28: #include <fcntl.h>
1.5 nicm 29: #include <paths.h>
1.1 nicm 30: #include <signal.h>
31: #include <stdio.h>
32: #include <stdlib.h>
33: #include <string.h>
34: #include <termios.h>
35: #include <time.h>
36: #include <unistd.h>
37:
38: #include "tmux.h"
39:
40: /*
41: * Main server functions.
42: */
43:
1.155 nicm 44: struct clients clients;
1.1 nicm 45:
1.155 nicm 46: struct tmuxproc *server_proc;
1.186 nicm 47: static int server_fd = -1;
1.188 nicm 48: static int server_client_flags;
1.160 nicm 49: static int server_exit;
50: static struct event server_ev_accept;
1.155 nicm 51:
52: struct cmd_find_state marked_pane;
1.126 nicm 53:
1.190 nicm 54: static u_int message_next;
55: struct message_list message_log;
56:
1.160 nicm 57: static int server_loop(void);
58: static void server_send_exit(void);
59: static void server_accept(int, short, void *);
60: static void server_signal(int);
61: static void server_child_signal(void);
62: static void server_child_exited(pid_t, int);
63: static void server_child_stopped(pid_t, int);
1.126 nicm 64:
65: /* Set marked pane. */
66: void
67: server_set_marked(struct session *s, struct winlink *wl, struct window_pane *wp)
68: {
1.169 nicm 69: cmd_find_clear_state(&marked_pane, 0);
1.155 nicm 70: marked_pane.s = s;
71: marked_pane.wl = wl;
72: marked_pane.w = wl->window;
73: marked_pane.wp = wp;
1.126 nicm 74: }
75:
76: /* Clear marked pane. */
77: void
78: server_clear_marked(void)
79: {
1.169 nicm 80: cmd_find_clear_state(&marked_pane, 0);
1.126 nicm 81: }
82:
83: /* Is this the marked pane? */
84: int
85: server_is_marked(struct session *s, struct winlink *wl, struct window_pane *wp)
86: {
87: if (s == NULL || wl == NULL || wp == NULL)
88: return (0);
1.155 nicm 89: if (marked_pane.s != s || marked_pane.wl != wl)
1.126 nicm 90: return (0);
1.155 nicm 91: if (marked_pane.wp != wp)
1.126 nicm 92: return (0);
93: return (server_check_marked());
94: }
95:
96: /* Check if the marked pane is still valid. */
97: int
98: server_check_marked(void)
99: {
1.155 nicm 100: return (cmd_find_valid_state(&marked_pane));
1.126 nicm 101: }
1.45 nicm 102:
1.60 nicm 103: /* Create server socket. */
1.160 nicm 104: static int
1.188 nicm 105: server_create_socket(int flags, char **cause)
1.1 nicm 106: {
1.60 nicm 107: struct sockaddr_un sa;
108: size_t size;
109: mode_t mask;
1.178 nicm 110: int fd, saved_errno;
1.60 nicm 111:
112: memset(&sa, 0, sizeof sa);
113: sa.sun_family = AF_UNIX;
114: size = strlcpy(sa.sun_path, socket_path, sizeof sa.sun_path);
115: if (size >= sizeof sa.sun_path) {
116: errno = ENAMETOOLONG;
1.178 nicm 117: goto fail;
1.60 nicm 118: }
119: unlink(sa.sun_path);
120:
121: if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
1.178 nicm 122: goto fail;
1.60 nicm 123:
1.188 nicm 124: if (flags & CLIENT_DEFAULTSOCKET)
125: mask = umask(S_IXUSR|S_IXGRP|S_IRWXO);
126: else
127: mask = umask(S_IXUSR|S_IRWXG|S_IRWXO);
1.178 nicm 128: if (bind(fd, (struct sockaddr *)&sa, sizeof sa) == -1) {
129: saved_errno = errno;
1.170 nicm 130: close(fd);
1.178 nicm 131: errno = saved_errno;
132: goto fail;
1.170 nicm 133: }
1.60 nicm 134: umask(mask);
135:
1.170 nicm 136: if (listen(fd, 128) == -1) {
1.178 nicm 137: saved_errno = errno;
1.170 nicm 138: close(fd);
1.178 nicm 139: errno = saved_errno;
140: goto fail;
1.170 nicm 141: }
1.100 nicm 142: setblocking(fd, 0);
1.1 nicm 143:
1.60 nicm 144: return (fd);
1.178 nicm 145:
146: fail:
147: if (cause != NULL) {
148: xasprintf(cause, "error creating %s (%s)", socket_path,
149: strerror(errno));
150: }
151: return (-1);
152: }
153:
1.1 nicm 154: /* Fork new server. */
155: int
1.188 nicm 156: server_start(struct tmuxproc *client, int flags, struct event_base *base,
157: int lockfd, char *lockfile)
1.1 nicm 158: {
1.167 nicm 159: int pair[2];
1.175 nicm 160: sigset_t set, oldset;
1.178 nicm 161: struct client *c;
162: char *cause = NULL;
1.1 nicm 163:
1.175 nicm 164: sigfillset(&set);
165: sigprocmask(SIG_BLOCK, &set, &oldset);
1.191 nicm 166:
167: if (~flags & CLIENT_NOFORK) {
168: if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pair) != 0)
169: fatal("socketpair failed");
170:
171: switch (fork()) {
172: case -1:
173: fatal("fork failed");
174: case 0:
175: break;
176: default:
177: sigprocmask(SIG_SETMASK, &oldset, NULL);
178: close(pair[1]);
179: return (pair[0]);
180: }
181: close(pair[0]);
182: if (daemon(1, 0) != 0)
183: fatal("daemon failed");
184: }
185:
186: server_client_flags = flags;
1.176 nicm 187: proc_clear_signals(client, 0);
1.191 nicm 188:
1.174 nicm 189: if (event_reinit(base) != 0)
190: fatalx("event_reinit failed");
191: server_proc = proc_start("server");
1.191 nicm 192:
1.174 nicm 193: proc_set_signals(server_proc, server_signal);
1.175 nicm 194: sigprocmask(SIG_SETMASK, &oldset, NULL);
1.143 nicm 195:
1.171 nicm 196: if (log_get_level() > 1)
1.146 nicm 197: tty_create_log();
1.151 nicm 198: if (pledge("stdio rpath wpath cpath fattr unix getpw recvfd proc exec "
199: "tty ps", NULL) != 0)
1.143 nicm 200: fatal("pledge failed");
1.1 nicm 201:
1.192 ! nicm 202: input_key_build();
1.121 nicm 203: RB_INIT(&windows);
1.102 nicm 204: RB_INIT(&all_window_panes);
1.122 nicm 205: TAILQ_INIT(&clients);
1.97 nicm 206: RB_INIT(&sessions);
1.1 nicm 207: key_bindings_init();
1.190 nicm 208: TAILQ_INIT(&message_log);
1.1 nicm 209:
1.153 nicm 210: gettimeofday(&start_time, NULL);
1.16 nicm 211:
1.188 nicm 212: server_fd = server_create_socket(flags, &cause);
1.178 nicm 213: if (server_fd != -1)
214: server_update_socket();
1.191 nicm 215: if (~flags & CLIENT_NOFORK)
216: c = server_client_create(pair[1]);
217: else
218: options_set_number(global_options, "exit-empty", 0);
1.103 nicm 219:
1.154 nicm 220: if (lockfd >= 0) {
221: unlink(lockfile);
222: free(lockfile);
223: close(lockfd);
224: }
1.16 nicm 225:
1.178 nicm 226: if (cause != NULL) {
1.185 nicm 227: cmdq_append(c, cmdq_get_error(cause));
228: free(cause);
1.178 nicm 229: c->flags |= CLIENT_EXIT;
1.187 nicm 230: }
1.178 nicm 231:
1.104 nicm 232: server_add_accept(0);
1.144 nicm 233: proc_loop(server_proc, server_loop);
1.167 nicm 234:
1.183 nicm 235: job_kill_all();
236: status_prompt_save_history();
1.167 nicm 237:
1.66 nicm 238: exit(0);
1.1 nicm 239: }
240:
1.144 nicm 241: /* Server loop callback. */
1.160 nicm 242: static int
1.66 nicm 243: server_loop(void)
1.1 nicm 244: {
1.144 nicm 245: struct client *c;
1.162 nicm 246: u_int items;
247:
248: do {
249: items = cmdq_next(NULL);
1.164 nicm 250: TAILQ_FOREACH(c, &clients, entry) {
251: if (c->flags & CLIENT_IDENTIFIED)
252: items += cmdq_next(c);
253: }
1.162 nicm 254: } while (items != 0);
1.31 nicm 255:
1.144 nicm 256: server_client_loop();
1.179 nicm 257:
258: if (!options_get_number(global_options, "exit-empty") && !server_exit)
259: return (0);
1.1 nicm 260:
1.145 nicm 261: if (!options_get_number(global_options, "exit-unattached")) {
1.97 nicm 262: if (!RB_EMPTY(&sessions))
263: return (0);
1.1 nicm 264: }
1.116 nicm 265:
1.122 nicm 266: TAILQ_FOREACH(c, &clients, entry) {
267: if (c->session != NULL)
1.116 nicm 268: return (0);
269: }
270:
271: /*
272: * No attached clients therefore want to exit - flush any waiting
273: * clients but don't actually exit until they've gone.
274: */
275: cmd_wait_for_flush();
1.122 nicm 276: if (!TAILQ_EMPTY(&clients))
277: return (0);
1.116 nicm 278:
1.183 nicm 279: if (job_still_running())
280: return (0);
1.180 nicm 281:
1.66 nicm 282: return (1);
1.1 nicm 283: }
284:
1.141 nicm 285: /* Exit the server by killing all clients and windows. */
1.160 nicm 286: static void
1.141 nicm 287: server_send_exit(void)
1.1 nicm 288: {
1.122 nicm 289: struct client *c, *c1;
290: struct session *s, *s1;
1.116 nicm 291:
292: cmd_wait_for_flush();
1.1 nicm 293:
1.122 nicm 294: TAILQ_FOREACH_SAFE(c, &clients, entry, c1) {
1.144 nicm 295: if (c->flags & CLIENT_SUSPENDED)
1.122 nicm 296: server_client_lost(c);
1.180 nicm 297: else {
298: if (c->flags & CLIENT_ATTACHED)
299: notify_client("client-detached", c);
1.144 nicm 300: proc_send(c->peer, MSG_SHUTDOWN, -1, NULL, 0);
1.180 nicm 301: }
1.122 nicm 302: c->session = NULL;
1.42 nicm 303: }
304:
1.122 nicm 305: RB_FOREACH_SAFE(s, sessions, &sessions, s1)
1.184 nicm 306: session_destroy(s, 1, __func__);
1.66 nicm 307: }
308:
309: /* Update socket execute permissions based on whether sessions are attached. */
1.75 nicm 310: void
1.66 nicm 311: server_update_socket(void)
1.42 nicm 312: {
1.66 nicm 313: struct session *s;
314: static int last = -1;
1.93 nicm 315: int n, mode;
316: struct stat sb;
1.1 nicm 317:
1.66 nicm 318: n = 0;
1.97 nicm 319: RB_FOREACH(s, sessions, &sessions) {
1.182 nicm 320: if (s->attached != 0) {
1.66 nicm 321: n++;
322: break;
323: }
324: }
325:
326: if (n != last) {
327: last = n;
1.93 nicm 328:
329: if (stat(socket_path, &sb) != 0)
330: return;
1.159 semarie 331: mode = sb.st_mode & ACCESSPERMS;
1.93 nicm 332: if (n != 0) {
333: if (mode & S_IRUSR)
334: mode |= S_IXUSR;
335: if (mode & S_IRGRP)
336: mode |= S_IXGRP;
337: if (mode & S_IROTH)
338: mode |= S_IXOTH;
339: } else
340: mode &= ~(S_IXUSR|S_IXGRP|S_IXOTH);
341: chmod(socket_path, mode);
1.66 nicm 342: }
343: }
344:
345: /* Callback for server socket. */
1.160 nicm 346: static void
1.150 nicm 347: server_accept(int fd, short events, __unused void *data)
1.66 nicm 348: {
349: struct sockaddr_storage sa;
350: socklen_t slen = sizeof sa;
351: int newfd;
352:
1.104 nicm 353: server_add_accept(0);
1.66 nicm 354: if (!(events & EV_READ))
355: return;
356:
357: newfd = accept(fd, (struct sockaddr *) &sa, &slen);
358: if (newfd == -1) {
359: if (errno == EAGAIN || errno == EINTR || errno == ECONNABORTED)
360: return;
1.104 nicm 361: if (errno == ENFILE || errno == EMFILE) {
362: /* Delete and don't try again for 1 second. */
363: server_add_accept(1);
364: return;
365: }
1.66 nicm 366: fatal("accept failed");
367: }
1.141 nicm 368: if (server_exit) {
1.66 nicm 369: close(newfd);
370: return;
1.42 nicm 371: }
1.66 nicm 372: server_client_create(newfd);
373: }
374:
1.104 nicm 375: /*
376: * Add accept event. If timeout is nonzero, add as a timeout instead of a read
377: * event - used to backoff when running out of file descriptors.
378: */
379: void
380: server_add_accept(int timeout)
381: {
382: struct timeval tv = { timeout, 0 };
1.186 nicm 383:
384: if (server_fd == -1)
385: return;
1.104 nicm 386:
387: if (event_initialized(&server_ev_accept))
388: event_del(&server_ev_accept);
389:
390: if (timeout == 0) {
1.144 nicm 391: event_set(&server_ev_accept, server_fd, EV_READ, server_accept,
392: NULL);
1.104 nicm 393: event_add(&server_ev_accept, NULL);
394: } else {
1.144 nicm 395: event_set(&server_ev_accept, server_fd, EV_TIMEOUT,
396: server_accept, NULL);
1.104 nicm 397: event_add(&server_ev_accept, &tv);
398: }
399: }
400:
1.66 nicm 401: /* Signal handler. */
1.160 nicm 402: static void
1.144 nicm 403: server_signal(int sig)
1.66 nicm 404: {
1.119 nicm 405: int fd;
1.120 nicm 406:
1.173 nicm 407: log_debug("%s: %s", __func__, strsignal(sig));
1.66 nicm 408: switch (sig) {
1.191 nicm 409: case SIGINT:
1.66 nicm 410: case SIGTERM:
1.141 nicm 411: server_exit = 1;
412: server_send_exit();
1.66 nicm 413: break;
414: case SIGCHLD:
415: server_child_signal();
416: break;
417: case SIGUSR1:
418: event_del(&server_ev_accept);
1.188 nicm 419: fd = server_create_socket(server_client_flags, NULL);
1.119 nicm 420: if (fd != -1) {
421: close(server_fd);
422: server_fd = fd;
423: server_update_socket();
424: }
1.104 nicm 425: server_add_accept(0);
1.171 nicm 426: break;
427: case SIGUSR2:
428: proc_toggle_log(server_proc);
1.66 nicm 429: break;
1.1 nicm 430: }
431: }
432:
433: /* Handle SIGCHLD. */
1.160 nicm 434: static void
1.1 nicm 435: server_child_signal(void)
436: {
1.66 nicm 437: int status;
438: pid_t pid;
1.1 nicm 439:
440: for (;;) {
441: switch (pid = waitpid(WAIT_ANY, &status, WNOHANG|WUNTRACED)) {
442: case -1:
443: if (errno == ECHILD)
444: return;
1.39 nicm 445: fatal("waitpid failed");
1.1 nicm 446: case 0:
447: return;
448: }
1.66 nicm 449: if (WIFSTOPPED(status))
450: server_child_stopped(pid, status);
1.79 nicm 451: else if (WIFEXITED(status) || WIFSIGNALED(status))
1.66 nicm 452: server_child_exited(pid, status);
453: }
454: }
455:
456: /* Handle exited children. */
1.160 nicm 457: static void
1.66 nicm 458: server_child_exited(pid_t pid, int status)
459: {
1.121 nicm 460: struct window *w, *w1;
1.66 nicm 461: struct window_pane *wp;
462:
1.121 nicm 463: RB_FOREACH_SAFE(w, windows, &windows, w1) {
1.66 nicm 464: TAILQ_FOREACH(wp, &w->panes, entry) {
465: if (wp->pid == pid) {
1.118 nicm 466: wp->status = status;
1.177 nicm 467: wp->flags |= PANE_STATUSREADY;
1.172 nicm 468:
469: log_debug("%%%u exited", wp->id);
470: wp->flags |= PANE_EXITED;
471:
472: if (window_pane_destroy_ready(wp))
473: server_destroy_pane(wp, 1);
1.77 nicm 474: break;
1.53 nicm 475: }
476: }
1.80 nicm 477: }
1.183 nicm 478: job_check_died(pid, status);
1.53 nicm 479: }
480:
1.66 nicm 481: /* Handle stopped children. */
1.160 nicm 482: static void
1.66 nicm 483: server_child_stopped(pid_t pid, int status)
1.31 nicm 484: {
1.66 nicm 485: struct window *w;
486: struct window_pane *wp;
1.31 nicm 487:
1.66 nicm 488: if (WSTOPSIG(status) == SIGTTIN || WSTOPSIG(status) == SIGTTOU)
489: return;
1.31 nicm 490:
1.121 nicm 491: RB_FOREACH(w, windows, &windows) {
1.66 nicm 492: TAILQ_FOREACH(wp, &w->panes, entry) {
493: if (wp->pid == pid) {
494: if (killpg(pid, SIGCONT) != 0)
495: kill(pid, SIGCONT);
496: }
1.1 nicm 497: }
498: }
1.189 nicm 499: job_check_died(pid, status);
1.190 nicm 500: }
501:
502: /* Add to message log. */
503: void
504: server_add_message(const char *fmt, ...)
505: {
506: struct message_entry *msg, *msg1;
507: char *s;
508: va_list ap;
509: u_int limit;
510:
511: va_start(ap, fmt);
512: xvasprintf(&s, fmt, ap);
513: va_end(ap);
514:
515: log_debug("message: %s", s);
516:
517: msg = xcalloc(1, sizeof *msg);
518: gettimeofday(&msg->msg_time, NULL);
519: msg->msg_num = message_next++;
520: msg->msg = s;
521: TAILQ_INSERT_TAIL(&message_log, msg, entry);
522:
523: limit = options_get_number(global_options, "message-limit");
524: TAILQ_FOREACH_SAFE(msg, &message_log, entry, msg1) {
525: if (msg->msg_num + limit >= message_next)
526: break;
527: free(msg->msg);
528: TAILQ_REMOVE(&message_log, msg, entry);
529: free(msg);
530: }
1.1 nicm 531: }