Annotation of src/usr.bin/tmux/server.c, Revision 1.116
1.116 ! nicm 1: /* $OpenBSD: server.c,v 1.115 2014/07/21 10:52:48 nicm Exp $ */
1.1 nicm 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/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 <syslog.h>
35: #include <termios.h>
36: #include <time.h>
37: #include <unistd.h>
38:
39: #include "tmux.h"
40:
41: /*
42: * Main server functions.
43: */
44:
45: /* Client list. */
46: struct clients clients;
1.31 nicm 47: struct clients dead_clients;
1.1 nicm 48:
1.66 nicm 49: int server_fd;
50: int server_shutdown;
51: struct event server_ev_accept;
52: struct event server_ev_second;
1.45 nicm 53:
1.1 nicm 54: int server_create_socket(void);
1.66 nicm 55: void server_loop(void);
1.42 nicm 56: int server_should_shutdown(void);
1.66 nicm 57: void server_send_shutdown(void);
58: void server_clean_dead(void);
59: void server_accept_callback(int, short, void *);
60: void server_signal_callback(int, short, void *);
1.1 nicm 61: void server_child_signal(void);
1.66 nicm 62: void server_child_exited(pid_t, int);
63: void server_child_stopped(pid_t, int);
64: void server_second_callback(int, short, void *);
1.46 nicm 65: void server_lock_server(void);
66: void server_lock_sessions(void);
1.45 nicm 67:
1.60 nicm 68: /* Create server socket. */
69: int
70: server_create_socket(void)
1.1 nicm 71: {
1.60 nicm 72: struct sockaddr_un sa;
73: size_t size;
74: mode_t mask;
1.100 nicm 75: int fd;
1.60 nicm 76:
77: memset(&sa, 0, sizeof sa);
78: sa.sun_family = AF_UNIX;
79: size = strlcpy(sa.sun_path, socket_path, sizeof sa.sun_path);
80: if (size >= sizeof sa.sun_path) {
81: errno = ENAMETOOLONG;
82: fatal("socket failed");
83: }
84: unlink(sa.sun_path);
85:
86: if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
87: fatal("socket failed");
88:
1.89 nicm 89: mask = umask(S_IXUSR|S_IXGRP|S_IRWXO);
1.60 nicm 90: if (bind(fd, (struct sockaddr *) &sa, SUN_LEN(&sa)) == -1)
91: fatal("bind failed");
92: umask(mask);
93:
94: if (listen(fd, 16) == -1)
95: fatal("listen failed");
1.100 nicm 96: setblocking(fd, 0);
1.1 nicm 97:
1.75 nicm 98: server_update_socket();
99:
1.60 nicm 100: return (fd);
101: }
102:
1.1 nicm 103: /* Fork new server. */
104: int
1.103 nicm 105: server_start(int lockfd, char *lockfile)
1.1 nicm 106: {
1.109 nicm 107: int pair[2];
108: struct timeval tv;
109: char *cause;
1.1 nicm 110:
111: /* The first client is special and gets a socketpair; create it. */
112: if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pair) != 0)
113: fatal("socketpair failed");
1.115 nicm 114: log_debug("starting server");
1.1 nicm 115:
116: switch (fork()) {
117: case -1:
118: fatal("fork failed");
119: case 0:
120: break;
121: default:
122: close(pair[1]);
123: return (pair[0]);
124: }
125: close(pair[0]);
126:
127: /*
128: * Must daemonise before loading configuration as the PID changes so
129: * $TMUX would be wrong for sessions created in the config file.
130: */
1.16 nicm 131: if (daemon(1, 0) != 0)
1.1 nicm 132: fatal("daemon failed");
133:
1.88 nicm 134: /* event_init() was called in our parent, need to reinit. */
135: if (event_reinit(ev_base) != 0)
136: fatal("event_reinit failed");
1.92 nicm 137: clear_signals(0);
1.88 nicm 138:
1.16 nicm 139: logfile("server");
140: log_debug("server started, pid %ld", (long) getpid());
141:
1.1 nicm 142: ARRAY_INIT(&windows);
1.102 nicm 143: RB_INIT(&all_window_panes);
1.1 nicm 144: ARRAY_INIT(&clients);
1.31 nicm 145: ARRAY_INIT(&dead_clients);
1.97 nicm 146: RB_INIT(&sessions);
147: RB_INIT(&dead_sessions);
1.47 nicm 148: TAILQ_INIT(&session_groups);
1.15 nicm 149: mode_key_init_trees();
1.1 nicm 150: key_bindings_init();
151: utf8_build();
152:
153: start_time = time(NULL);
1.16 nicm 154: log_debug("socket path %s", socket_path);
1.96 nicm 155: setproctitle("server (%s)", socket_path);
1.16 nicm 156:
1.66 nicm 157: server_fd = server_create_socket();
1.60 nicm 158: server_client_create(pair[1]);
1.103 nicm 159:
160: unlink(lockfile);
1.105 nicm 161: free(lockfile);
1.103 nicm 162: close(lockfd);
1.16 nicm 163:
1.109 nicm 164: cfg_cmd_q = cmdq_new(NULL);
165: cfg_cmd_q->emptyfn = cfg_default_done;
166: cfg_finished = 0;
167: cfg_references = 1;
168: ARRAY_INIT(&cfg_causes);
1.111 nicm 169: cfg_client = ARRAY_FIRST(&clients);
170: if (cfg_client != NULL)
171: cfg_client->references++;
1.109 nicm 172:
1.110 nicm 173: if (access(TMUX_CONF, R_OK) == 0) {
174: if (load_cfg(TMUX_CONF, cfg_cmd_q, &cause) == -1) {
175: xasprintf(&cause, "%s: %s", TMUX_CONF, cause);
1.109 nicm 176: ARRAY_ADD(&cfg_causes, cause);
177: }
178: } else if (errno != ENOENT) {
1.110 nicm 179: xasprintf(&cause, "%s: %s", TMUX_CONF, strerror(errno));
1.109 nicm 180: ARRAY_ADD(&cfg_causes, cause);
1.64 nicm 181: }
1.109 nicm 182: if (cfg_file != NULL) {
183: if (load_cfg(cfg_file, cfg_cmd_q, &cause) == -1) {
184: xasprintf(&cause, "%s: %s", cfg_file, cause);
185: ARRAY_ADD(&cfg_causes, cause);
186: }
187: }
188: cmdq_continue(cfg_cmd_q);
1.66 nicm 189:
1.104 nicm 190: server_add_accept(0);
1.66 nicm 191:
192: memset(&tv, 0, sizeof tv);
193: tv.tv_sec = 1;
194: evtimer_set(&server_ev_second, server_second_callback, NULL);
195: evtimer_add(&server_ev_second, &tv);
196:
1.88 nicm 197: set_signals(server_signal_callback);
1.66 nicm 198: server_loop();
199: exit(0);
1.1 nicm 200: }
201:
202: /* Main server loop. */
1.66 nicm 203: void
204: server_loop(void)
1.1 nicm 205: {
1.66 nicm 206: while (!server_should_shutdown()) {
207: event_loop(EVLOOP_ONCE);
1.1 nicm 208:
1.60 nicm 209: server_window_loop();
210: server_client_loop();
1.1 nicm 211:
1.66 nicm 212: server_clean_dead();
1.80 nicm 213: }
1.66 nicm 214: }
1.31 nicm 215:
1.112 nicm 216: /* Check if the server should exit (no more clients or sessions). */
1.66 nicm 217: int
218: server_should_shutdown(void)
219: {
1.116 ! nicm 220: struct client *c;
! 221: u_int i;
1.1 nicm 222:
1.94 nicm 223: if (!options_get_number(&global_options, "exit-unattached")) {
1.97 nicm 224: if (!RB_EMPTY(&sessions))
225: return (0);
1.1 nicm 226: }
1.116 ! nicm 227:
! 228: for (i = 0; i < ARRAY_LENGTH(&clients); i++) {
! 229: c = ARRAY_ITEM(&clients, i);
! 230: if (c != NULL && c->session != NULL)
! 231: return (0);
! 232: }
! 233:
! 234: /*
! 235: * No attached clients therefore want to exit - flush any waiting
! 236: * clients but don't actually exit until they've gone.
! 237: */
! 238: cmd_wait_for_flush();
1.1 nicm 239: for (i = 0; i < ARRAY_LENGTH(&clients); i++) {
240: if (ARRAY_ITEM(&clients, i) != NULL)
1.66 nicm 241: return (0);
1.1 nicm 242: }
1.116 ! nicm 243:
1.66 nicm 244: return (1);
1.1 nicm 245: }
246:
1.66 nicm 247: /* Shutdown the server by killing all clients and windows. */
1.1 nicm 248: void
1.66 nicm 249: server_send_shutdown(void)
1.1 nicm 250: {
1.66 nicm 251: struct client *c;
1.97 nicm 252: struct session *s, *next_s;
1.66 nicm 253: u_int i;
1.116 ! nicm 254:
! 255: cmd_wait_for_flush();
1.1 nicm 256:
1.42 nicm 257: for (i = 0; i < ARRAY_LENGTH(&clients); i++) {
258: c = ARRAY_ITEM(&clients, i);
259: if (c != NULL) {
260: if (c->flags & (CLIENT_BAD|CLIENT_SUSPENDED))
1.60 nicm 261: server_client_lost(c);
1.42 nicm 262: else
263: server_write_client(c, MSG_SHUTDOWN, NULL, 0);
1.66 nicm 264: c->session = NULL;
1.42 nicm 265: }
266: }
267:
1.97 nicm 268: s = RB_MIN(sessions, &sessions);
269: while (s != NULL) {
270: next_s = RB_NEXT(sessions, &sessions, s);
271: session_destroy(s);
272: s = next_s;
1.1 nicm 273: }
1.42 nicm 274: }
275:
1.66 nicm 276: /* Free dead, unreferenced clients and sessions. */
277: void
278: server_clean_dead(void)
279: {
1.97 nicm 280: struct session *s, *next_s;
1.66 nicm 281: struct client *c;
282: u_int i;
283:
1.97 nicm 284: s = RB_MIN(sessions, &dead_sessions);
285: while (s != NULL) {
286: next_s = RB_NEXT(sessions, &dead_sessions, s);
287: if (s->references == 0) {
288: RB_REMOVE(sessions, &dead_sessions, s);
1.105 nicm 289: free(s->name);
290: free(s);
1.97 nicm 291: }
292: s = next_s;
1.66 nicm 293: }
294:
295: for (i = 0; i < ARRAY_LENGTH(&dead_clients); i++) {
296: c = ARRAY_ITEM(&dead_clients, i);
297: if (c == NULL || c->references != 0)
298: continue;
299: ARRAY_SET(&dead_clients, i, NULL);
1.105 nicm 300: free(c);
1.66 nicm 301: }
302: }
303:
304: /* Update socket execute permissions based on whether sessions are attached. */
1.75 nicm 305: void
1.66 nicm 306: server_update_socket(void)
1.42 nicm 307: {
1.66 nicm 308: struct session *s;
309: static int last = -1;
1.93 nicm 310: int n, mode;
311: struct stat sb;
1.1 nicm 312:
1.66 nicm 313: n = 0;
1.97 nicm 314: RB_FOREACH(s, sessions, &sessions) {
315: if (!(s->flags & SESSION_UNATTACHED)) {
1.66 nicm 316: n++;
317: break;
318: }
319: }
320:
321: if (n != last) {
322: last = n;
1.93 nicm 323:
324: if (stat(socket_path, &sb) != 0)
325: return;
326: mode = sb.st_mode;
327: if (n != 0) {
328: if (mode & S_IRUSR)
329: mode |= S_IXUSR;
330: if (mode & S_IRGRP)
331: mode |= S_IXGRP;
332: if (mode & S_IROTH)
333: mode |= S_IXOTH;
334: } else
335: mode &= ~(S_IXUSR|S_IXGRP|S_IXOTH);
336: chmod(socket_path, mode);
1.66 nicm 337: }
338: }
339:
340: /* Callback for server socket. */
341: void
342: server_accept_callback(int fd, short events, unused void *data)
343: {
344: struct sockaddr_storage sa;
345: socklen_t slen = sizeof sa;
346: int newfd;
347:
1.104 nicm 348: server_add_accept(0);
1.66 nicm 349: if (!(events & EV_READ))
350: return;
351:
352: newfd = accept(fd, (struct sockaddr *) &sa, &slen);
353: if (newfd == -1) {
354: if (errno == EAGAIN || errno == EINTR || errno == ECONNABORTED)
355: return;
1.104 nicm 356: if (errno == ENFILE || errno == EMFILE) {
357: /* Delete and don't try again for 1 second. */
358: server_add_accept(1);
359: return;
360: }
1.66 nicm 361: fatal("accept failed");
362: }
363: if (server_shutdown) {
364: close(newfd);
365: return;
1.42 nicm 366: }
1.66 nicm 367: server_client_create(newfd);
368: }
369:
1.104 nicm 370: /*
371: * Add accept event. If timeout is nonzero, add as a timeout instead of a read
372: * event - used to backoff when running out of file descriptors.
373: */
374: void
375: server_add_accept(int timeout)
376: {
377: struct timeval tv = { timeout, 0 };
378:
379: if (event_initialized(&server_ev_accept))
380: event_del(&server_ev_accept);
381:
382: if (timeout == 0) {
383: event_set(&server_ev_accept,
384: server_fd, EV_READ, server_accept_callback, NULL);
385: event_add(&server_ev_accept, NULL);
386: } else {
387: event_set(&server_ev_accept,
388: server_fd, EV_TIMEOUT, server_accept_callback, NULL);
389: event_add(&server_ev_accept, &tv);
390: }
391: }
392:
1.66 nicm 393: /* Signal handler. */
394: void
395: server_signal_callback(int sig, unused short events, unused void *data)
396: {
397: switch (sig) {
398: case SIGTERM:
399: server_shutdown = 1;
400: server_send_shutdown();
401: break;
402: case SIGCHLD:
403: server_child_signal();
404: break;
405: case SIGUSR1:
406: event_del(&server_ev_accept);
407: close(server_fd);
408: server_fd = server_create_socket();
1.104 nicm 409: server_add_accept(0);
1.66 nicm 410: break;
1.1 nicm 411: }
412: }
413:
414: /* Handle SIGCHLD. */
415: void
416: server_child_signal(void)
417: {
1.66 nicm 418: int status;
419: pid_t pid;
1.1 nicm 420:
421: for (;;) {
422: switch (pid = waitpid(WAIT_ANY, &status, WNOHANG|WUNTRACED)) {
423: case -1:
424: if (errno == ECHILD)
425: return;
1.39 nicm 426: fatal("waitpid failed");
1.1 nicm 427: case 0:
428: return;
429: }
1.66 nicm 430: if (WIFSTOPPED(status))
431: server_child_stopped(pid, status);
1.79 nicm 432: else if (WIFEXITED(status) || WIFSIGNALED(status))
1.66 nicm 433: server_child_exited(pid, status);
434: }
435: }
436:
437: /* Handle exited children. */
438: void
439: server_child_exited(pid_t pid, int status)
440: {
441: struct window *w;
442: struct window_pane *wp;
443: struct job *job;
444: u_int i;
445:
446: for (i = 0; i < ARRAY_LENGTH(&windows); i++) {
447: if ((w = ARRAY_ITEM(&windows, i)) == NULL)
448: continue;
449: TAILQ_FOREACH(wp, &w->panes, entry) {
450: if (wp->pid == pid) {
1.77 nicm 451: server_destroy_pane(wp);
452: break;
1.53 nicm 453: }
454: }
1.80 nicm 455: }
1.1 nicm 456:
1.101 nicm 457: LIST_FOREACH(job, &all_jobs, lentry) {
1.66 nicm 458: if (pid == job->pid) {
1.67 nicm 459: job_died(job, status); /* might free job */
460: break;
1.1 nicm 461: }
1.53 nicm 462: }
463: }
464:
1.66 nicm 465: /* Handle stopped children. */
1.31 nicm 466: void
1.66 nicm 467: server_child_stopped(pid_t pid, int status)
1.31 nicm 468: {
1.66 nicm 469: struct window *w;
470: struct window_pane *wp;
471: u_int i;
1.31 nicm 472:
1.66 nicm 473: if (WSTOPSIG(status) == SIGTTIN || WSTOPSIG(status) == SIGTTOU)
474: return;
1.31 nicm 475:
1.66 nicm 476: for (i = 0; i < ARRAY_LENGTH(&windows); i++) {
477: if ((w = ARRAY_ITEM(&windows, i)) == NULL)
1.31 nicm 478: continue;
1.66 nicm 479: TAILQ_FOREACH(wp, &w->panes, entry) {
480: if (wp->pid == pid) {
481: if (killpg(pid, SIGCONT) != 0)
482: kill(pid, SIGCONT);
483: }
484: }
1.31 nicm 485: }
1.1 nicm 486: }
487:
1.66 nicm 488: /* Handle once-per-second timer events. */
1.1 nicm 489: void
1.66 nicm 490: server_second_callback(unused int fd, unused short events, unused void *arg)
1.1 nicm 491: {
1.60 nicm 492: struct window *w;
493: struct window_pane *wp;
1.66 nicm 494: struct timeval tv;
1.35 nicm 495: u_int i;
1.1 nicm 496:
1.60 nicm 497: if (options_get_number(&global_s_options, "lock-server"))
498: server_lock_server();
499: else
500: server_lock_sessions();
1.1 nicm 501:
1.60 nicm 502: for (i = 0; i < ARRAY_LENGTH(&windows); i++) {
503: w = ARRAY_ITEM(&windows, i);
504: if (w == NULL)
1.1 nicm 505: continue;
506:
1.60 nicm 507: TAILQ_FOREACH(wp, &w->panes, entry) {
508: if (wp->mode != NULL && wp->mode->timer != NULL)
509: wp->mode->timer(wp);
1.1 nicm 510: }
511: }
1.72 nicm 512:
513: server_client_status_timer();
1.66 nicm 514:
515: evtimer_del(&server_ev_second);
516: memset(&tv, 0, sizeof tv);
517: tv.tv_sec = 1;
518: evtimer_add(&server_ev_second, &tv);
1.1 nicm 519: }
520:
1.46 nicm 521: /* Lock the server if ALL sessions have hit the time limit. */
522: void
523: server_lock_server(void)
524: {
525: struct session *s;
526: int timeout;
527: time_t t;
528:
529: t = time(NULL);
1.97 nicm 530: RB_FOREACH(s, sessions, &sessions) {
1.99 nicm 531: if (s->flags & SESSION_UNATTACHED)
1.59 nicm 532: continue;
1.46 nicm 533: timeout = options_get_number(&s->options, "lock-after-time");
1.65 nicm 534: if (timeout <= 0 || t <= s->activity_time.tv_sec + timeout)
1.46 nicm 535: return; /* not timed out */
536: }
537:
538: server_lock();
539: recalculate_sizes();
540: }
541:
542: /* Lock any sessions which have timed out. */
543: void
544: server_lock_sessions(void)
545: {
1.80 nicm 546: struct session *s;
1.46 nicm 547: int timeout;
1.62 deraadt 548: time_t t;
1.46 nicm 549:
1.62 deraadt 550: t = time(NULL);
1.97 nicm 551: RB_FOREACH(s, sessions, &sessions) {
1.99 nicm 552: if (s->flags & SESSION_UNATTACHED)
1.59 nicm 553: continue;
1.46 nicm 554: timeout = options_get_number(&s->options, "lock-after-time");
1.65 nicm 555: if (timeout > 0 && t > s->activity_time.tv_sec + timeout) {
1.46 nicm 556: server_lock_session(s);
557: recalculate_sizes();
1.1 nicm 558: }
559: }
560: }