Annotation of src/usr.bin/tmux/server.c, Revision 1.111
1.111 ! nicm 1: /* $OpenBSD: server.c,v 1.110 2013/04/24 10:01:32 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:
1.98 nicm 54: struct paste_stack global_buffers;
55:
1.1 nicm 56: int server_create_socket(void);
1.66 nicm 57: void server_loop(void);
1.42 nicm 58: int server_should_shutdown(void);
1.66 nicm 59: void server_send_shutdown(void);
60: void server_clean_dead(void);
61: void server_accept_callback(int, short, void *);
62: void server_signal_callback(int, short, void *);
1.1 nicm 63: void server_child_signal(void);
1.66 nicm 64: void server_child_exited(pid_t, int);
65: void server_child_stopped(pid_t, int);
66: void server_second_callback(int, short, void *);
1.46 nicm 67: void server_lock_server(void);
68: void server_lock_sessions(void);
1.45 nicm 69:
1.60 nicm 70: /* Create server socket. */
71: int
72: server_create_socket(void)
1.1 nicm 73: {
1.60 nicm 74: struct sockaddr_un sa;
75: size_t size;
76: mode_t mask;
1.100 nicm 77: int fd;
1.60 nicm 78:
79: memset(&sa, 0, sizeof sa);
80: sa.sun_family = AF_UNIX;
81: size = strlcpy(sa.sun_path, socket_path, sizeof sa.sun_path);
82: if (size >= sizeof sa.sun_path) {
83: errno = ENAMETOOLONG;
84: fatal("socket failed");
85: }
86: unlink(sa.sun_path);
87:
88: if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
89: fatal("socket failed");
90:
1.89 nicm 91: mask = umask(S_IXUSR|S_IXGRP|S_IRWXO);
1.60 nicm 92: if (bind(fd, (struct sockaddr *) &sa, SUN_LEN(&sa)) == -1)
93: fatal("bind failed");
94: umask(mask);
95:
96: if (listen(fd, 16) == -1)
97: fatal("listen failed");
1.100 nicm 98: setblocking(fd, 0);
1.1 nicm 99:
1.75 nicm 100: server_update_socket();
101:
1.60 nicm 102: return (fd);
103: }
104:
1.1 nicm 105: /* Fork new server. */
106: int
1.103 nicm 107: server_start(int lockfd, char *lockfile)
1.1 nicm 108: {
1.109 nicm 109: int pair[2];
110: struct timeval tv;
111: char *cause;
1.1 nicm 112:
113: /* The first client is special and gets a socketpair; create it. */
114: if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pair) != 0)
115: fatal("socketpair failed");
116:
117: switch (fork()) {
118: case -1:
119: fatal("fork failed");
120: case 0:
121: break;
122: default:
123: close(pair[1]);
124: return (pair[0]);
125: }
126: close(pair[0]);
127:
128: /*
129: * Must daemonise before loading configuration as the PID changes so
130: * $TMUX would be wrong for sessions created in the config file.
131: */
1.16 nicm 132: if (daemon(1, 0) != 0)
1.1 nicm 133: fatal("daemon failed");
134:
1.88 nicm 135: /* event_init() was called in our parent, need to reinit. */
136: if (event_reinit(ev_base) != 0)
137: fatal("event_reinit failed");
1.92 nicm 138: clear_signals(0);
1.88 nicm 139:
1.16 nicm 140: logfile("server");
141: log_debug("server started, pid %ld", (long) getpid());
142:
1.1 nicm 143: ARRAY_INIT(&windows);
1.102 nicm 144: RB_INIT(&all_window_panes);
1.1 nicm 145: ARRAY_INIT(&clients);
1.31 nicm 146: ARRAY_INIT(&dead_clients);
1.97 nicm 147: RB_INIT(&sessions);
148: RB_INIT(&dead_sessions);
1.47 nicm 149: TAILQ_INIT(&session_groups);
1.98 nicm 150: ARRAY_INIT(&global_buffers);
1.15 nicm 151: mode_key_init_trees();
1.1 nicm 152: key_bindings_init();
153: utf8_build();
154:
155: start_time = time(NULL);
1.16 nicm 156: log_debug("socket path %s", socket_path);
1.96 nicm 157: setproctitle("server (%s)", socket_path);
1.16 nicm 158:
1.66 nicm 159: server_fd = server_create_socket();
1.60 nicm 160: server_client_create(pair[1]);
1.103 nicm 161:
162: unlink(lockfile);
1.105 nicm 163: free(lockfile);
1.103 nicm 164: close(lockfd);
1.16 nicm 165:
1.109 nicm 166: cfg_cmd_q = cmdq_new(NULL);
167: cfg_cmd_q->emptyfn = cfg_default_done;
168: cfg_finished = 0;
169: cfg_references = 1;
170: ARRAY_INIT(&cfg_causes);
1.111 ! nicm 171: cfg_client = ARRAY_FIRST(&clients);
! 172: if (cfg_client != NULL)
! 173: cfg_client->references++;
1.109 nicm 174:
1.110 nicm 175: if (access(TMUX_CONF, R_OK) == 0) {
176: if (load_cfg(TMUX_CONF, cfg_cmd_q, &cause) == -1) {
177: xasprintf(&cause, "%s: %s", TMUX_CONF, cause);
1.109 nicm 178: ARRAY_ADD(&cfg_causes, cause);
179: }
180: } else if (errno != ENOENT) {
1.110 nicm 181: xasprintf(&cause, "%s: %s", TMUX_CONF, strerror(errno));
1.109 nicm 182: ARRAY_ADD(&cfg_causes, cause);
1.64 nicm 183: }
1.109 nicm 184: if (cfg_file != NULL) {
185: if (load_cfg(cfg_file, cfg_cmd_q, &cause) == -1) {
186: xasprintf(&cause, "%s: %s", cfg_file, cause);
187: ARRAY_ADD(&cfg_causes, cause);
188: }
189: }
190: cmdq_continue(cfg_cmd_q);
1.66 nicm 191:
1.104 nicm 192: server_add_accept(0);
1.66 nicm 193:
194: memset(&tv, 0, sizeof tv);
195: tv.tv_sec = 1;
196: evtimer_set(&server_ev_second, server_second_callback, NULL);
197: evtimer_add(&server_ev_second, &tv);
198:
1.88 nicm 199: set_signals(server_signal_callback);
1.66 nicm 200: server_loop();
201: exit(0);
1.1 nicm 202: }
203:
204: /* Main server loop. */
1.66 nicm 205: void
206: server_loop(void)
1.1 nicm 207: {
1.66 nicm 208: while (!server_should_shutdown()) {
209: event_loop(EVLOOP_ONCE);
1.1 nicm 210:
1.60 nicm 211: server_window_loop();
212: server_client_loop();
1.1 nicm 213:
1.8 nicm 214: key_bindings_clean();
1.66 nicm 215: server_clean_dead();
1.80 nicm 216: }
1.66 nicm 217: }
1.31 nicm 218:
1.94 nicm 219: /* Check if the server should be shutting down (no more clients or sessions). */
1.66 nicm 220: int
221: server_should_shutdown(void)
222: {
223: u_int i;
1.1 nicm 224:
1.94 nicm 225: if (!options_get_number(&global_options, "exit-unattached")) {
1.97 nicm 226: if (!RB_EMPTY(&sessions))
227: return (0);
1.1 nicm 228: }
229: for (i = 0; i < ARRAY_LENGTH(&clients); i++) {
230: if (ARRAY_ITEM(&clients, i) != NULL)
1.66 nicm 231: return (0);
1.1 nicm 232: }
1.66 nicm 233: return (1);
1.1 nicm 234: }
235:
1.66 nicm 236: /* Shutdown the server by killing all clients and windows. */
1.1 nicm 237: void
1.66 nicm 238: server_send_shutdown(void)
1.1 nicm 239: {
1.66 nicm 240: struct client *c;
1.97 nicm 241: struct session *s, *next_s;
1.66 nicm 242: u_int i;
1.1 nicm 243:
1.42 nicm 244: for (i = 0; i < ARRAY_LENGTH(&clients); i++) {
245: c = ARRAY_ITEM(&clients, i);
246: if (c != NULL) {
247: if (c->flags & (CLIENT_BAD|CLIENT_SUSPENDED))
1.60 nicm 248: server_client_lost(c);
1.42 nicm 249: else
250: server_write_client(c, MSG_SHUTDOWN, NULL, 0);
1.66 nicm 251: c->session = NULL;
1.42 nicm 252: }
253: }
254:
1.97 nicm 255: s = RB_MIN(sessions, &sessions);
256: while (s != NULL) {
257: next_s = RB_NEXT(sessions, &sessions, s);
258: session_destroy(s);
259: s = next_s;
1.1 nicm 260: }
1.42 nicm 261: }
262:
1.66 nicm 263: /* Free dead, unreferenced clients and sessions. */
264: void
265: server_clean_dead(void)
266: {
1.97 nicm 267: struct session *s, *next_s;
1.66 nicm 268: struct client *c;
269: u_int i;
270:
1.97 nicm 271: s = RB_MIN(sessions, &dead_sessions);
272: while (s != NULL) {
273: next_s = RB_NEXT(sessions, &dead_sessions, s);
274: if (s->references == 0) {
275: RB_REMOVE(sessions, &dead_sessions, s);
1.105 nicm 276: free(s->name);
277: free(s);
1.97 nicm 278: }
279: s = next_s;
1.66 nicm 280: }
281:
282: for (i = 0; i < ARRAY_LENGTH(&dead_clients); i++) {
283: c = ARRAY_ITEM(&dead_clients, i);
284: if (c == NULL || c->references != 0)
285: continue;
286: ARRAY_SET(&dead_clients, i, NULL);
1.105 nicm 287: free(c);
1.66 nicm 288: }
289: }
290:
291: /* Update socket execute permissions based on whether sessions are attached. */
1.75 nicm 292: void
1.66 nicm 293: server_update_socket(void)
1.42 nicm 294: {
1.66 nicm 295: struct session *s;
296: static int last = -1;
1.93 nicm 297: int n, mode;
298: struct stat sb;
1.1 nicm 299:
1.66 nicm 300: n = 0;
1.97 nicm 301: RB_FOREACH(s, sessions, &sessions) {
302: if (!(s->flags & SESSION_UNATTACHED)) {
1.66 nicm 303: n++;
304: break;
305: }
306: }
307:
308: if (n != last) {
309: last = n;
1.93 nicm 310:
311: if (stat(socket_path, &sb) != 0)
312: return;
313: mode = sb.st_mode;
314: if (n != 0) {
315: if (mode & S_IRUSR)
316: mode |= S_IXUSR;
317: if (mode & S_IRGRP)
318: mode |= S_IXGRP;
319: if (mode & S_IROTH)
320: mode |= S_IXOTH;
321: } else
322: mode &= ~(S_IXUSR|S_IXGRP|S_IXOTH);
323: chmod(socket_path, mode);
1.66 nicm 324: }
325: }
326:
327: /* Callback for server socket. */
328: void
329: server_accept_callback(int fd, short events, unused void *data)
330: {
331: struct sockaddr_storage sa;
332: socklen_t slen = sizeof sa;
333: int newfd;
334:
1.104 nicm 335: server_add_accept(0);
1.66 nicm 336: if (!(events & EV_READ))
337: return;
338:
339: newfd = accept(fd, (struct sockaddr *) &sa, &slen);
340: if (newfd == -1) {
341: if (errno == EAGAIN || errno == EINTR || errno == ECONNABORTED)
342: return;
1.104 nicm 343: if (errno == ENFILE || errno == EMFILE) {
344: /* Delete and don't try again for 1 second. */
345: server_add_accept(1);
346: return;
347: }
1.66 nicm 348: fatal("accept failed");
349: }
350: if (server_shutdown) {
351: close(newfd);
352: return;
1.42 nicm 353: }
1.66 nicm 354: server_client_create(newfd);
355: }
356:
1.104 nicm 357: /*
358: * Add accept event. If timeout is nonzero, add as a timeout instead of a read
359: * event - used to backoff when running out of file descriptors.
360: */
361: void
362: server_add_accept(int timeout)
363: {
364: struct timeval tv = { timeout, 0 };
365:
366: if (event_initialized(&server_ev_accept))
367: event_del(&server_ev_accept);
368:
369: if (timeout == 0) {
370: event_set(&server_ev_accept,
371: server_fd, EV_READ, server_accept_callback, NULL);
372: event_add(&server_ev_accept, NULL);
373: } else {
374: event_set(&server_ev_accept,
375: server_fd, EV_TIMEOUT, server_accept_callback, NULL);
376: event_add(&server_ev_accept, &tv);
377: }
378: }
379:
1.66 nicm 380: /* Signal handler. */
381: void
382: server_signal_callback(int sig, unused short events, unused void *data)
383: {
384: switch (sig) {
385: case SIGTERM:
386: server_shutdown = 1;
387: server_send_shutdown();
388: break;
389: case SIGCHLD:
390: server_child_signal();
391: break;
392: case SIGUSR1:
393: event_del(&server_ev_accept);
394: close(server_fd);
395: server_fd = server_create_socket();
1.104 nicm 396: server_add_accept(0);
1.66 nicm 397: break;
1.1 nicm 398: }
399: }
400:
401: /* Handle SIGCHLD. */
402: void
403: server_child_signal(void)
404: {
1.66 nicm 405: int status;
406: pid_t pid;
1.1 nicm 407:
408: for (;;) {
409: switch (pid = waitpid(WAIT_ANY, &status, WNOHANG|WUNTRACED)) {
410: case -1:
411: if (errno == ECHILD)
412: return;
1.39 nicm 413: fatal("waitpid failed");
1.1 nicm 414: case 0:
415: return;
416: }
1.66 nicm 417: if (WIFSTOPPED(status))
418: server_child_stopped(pid, status);
1.79 nicm 419: else if (WIFEXITED(status) || WIFSIGNALED(status))
1.66 nicm 420: server_child_exited(pid, status);
421: }
422: }
423:
424: /* Handle exited children. */
425: void
426: server_child_exited(pid_t pid, int status)
427: {
428: struct window *w;
429: struct window_pane *wp;
430: struct job *job;
431: u_int i;
432:
433: for (i = 0; i < ARRAY_LENGTH(&windows); i++) {
434: if ((w = ARRAY_ITEM(&windows, i)) == NULL)
435: continue;
436: TAILQ_FOREACH(wp, &w->panes, entry) {
437: if (wp->pid == pid) {
1.77 nicm 438: server_destroy_pane(wp);
439: break;
1.53 nicm 440: }
441: }
1.80 nicm 442: }
1.1 nicm 443:
1.101 nicm 444: LIST_FOREACH(job, &all_jobs, lentry) {
1.66 nicm 445: if (pid == job->pid) {
1.67 nicm 446: job_died(job, status); /* might free job */
447: break;
1.1 nicm 448: }
1.53 nicm 449: }
450: }
451:
1.66 nicm 452: /* Handle stopped children. */
1.31 nicm 453: void
1.66 nicm 454: server_child_stopped(pid_t pid, int status)
1.31 nicm 455: {
1.66 nicm 456: struct window *w;
457: struct window_pane *wp;
458: u_int i;
1.31 nicm 459:
1.66 nicm 460: if (WSTOPSIG(status) == SIGTTIN || WSTOPSIG(status) == SIGTTOU)
461: return;
1.31 nicm 462:
1.66 nicm 463: for (i = 0; i < ARRAY_LENGTH(&windows); i++) {
464: if ((w = ARRAY_ITEM(&windows, i)) == NULL)
1.31 nicm 465: continue;
1.66 nicm 466: TAILQ_FOREACH(wp, &w->panes, entry) {
467: if (wp->pid == pid) {
468: if (killpg(pid, SIGCONT) != 0)
469: kill(pid, SIGCONT);
470: }
471: }
1.31 nicm 472: }
1.1 nicm 473: }
474:
1.66 nicm 475: /* Handle once-per-second timer events. */
1.1 nicm 476: void
1.66 nicm 477: server_second_callback(unused int fd, unused short events, unused void *arg)
1.1 nicm 478: {
1.60 nicm 479: struct window *w;
480: struct window_pane *wp;
1.66 nicm 481: struct timeval tv;
1.35 nicm 482: u_int i;
1.1 nicm 483:
1.60 nicm 484: if (options_get_number(&global_s_options, "lock-server"))
485: server_lock_server();
486: else
487: server_lock_sessions();
1.1 nicm 488:
1.60 nicm 489: for (i = 0; i < ARRAY_LENGTH(&windows); i++) {
490: w = ARRAY_ITEM(&windows, i);
491: if (w == NULL)
1.1 nicm 492: continue;
493:
1.60 nicm 494: TAILQ_FOREACH(wp, &w->panes, entry) {
495: if (wp->mode != NULL && wp->mode->timer != NULL)
496: wp->mode->timer(wp);
1.1 nicm 497: }
498: }
1.72 nicm 499:
500: server_client_status_timer();
1.66 nicm 501:
502: evtimer_del(&server_ev_second);
503: memset(&tv, 0, sizeof tv);
504: tv.tv_sec = 1;
505: evtimer_add(&server_ev_second, &tv);
1.1 nicm 506: }
507:
1.46 nicm 508: /* Lock the server if ALL sessions have hit the time limit. */
509: void
510: server_lock_server(void)
511: {
512: struct session *s;
513: int timeout;
514: time_t t;
515:
516: t = time(NULL);
1.97 nicm 517: RB_FOREACH(s, sessions, &sessions) {
1.99 nicm 518: if (s->flags & SESSION_UNATTACHED)
1.59 nicm 519: continue;
1.46 nicm 520: timeout = options_get_number(&s->options, "lock-after-time");
1.65 nicm 521: if (timeout <= 0 || t <= s->activity_time.tv_sec + timeout)
1.46 nicm 522: return; /* not timed out */
523: }
524:
525: server_lock();
526: recalculate_sizes();
527: }
528:
529: /* Lock any sessions which have timed out. */
530: void
531: server_lock_sessions(void)
532: {
1.80 nicm 533: struct session *s;
1.46 nicm 534: int timeout;
1.62 deraadt 535: time_t t;
1.46 nicm 536:
1.62 deraadt 537: t = time(NULL);
1.97 nicm 538: RB_FOREACH(s, sessions, &sessions) {
1.99 nicm 539: if (s->flags & SESSION_UNATTACHED)
1.59 nicm 540: continue;
1.46 nicm 541: timeout = options_get_number(&s->options, "lock-after-time");
1.65 nicm 542: if (timeout > 0 && t > s->activity_time.tv_sec + timeout) {
1.46 nicm 543: server_lock_session(s);
544: recalculate_sizes();
1.1 nicm 545: }
546: }
547: }