Annotation of src/usr.bin/tmux/server.c, Revision 1.138
1.138 ! nicm 1: /* $OpenBSD: server.c,v 1.137 2015/08/29 08:54:41 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 <termios.h>
35: #include <time.h>
36: #include <unistd.h>
37:
38: #include "tmux.h"
39:
40: /*
41: * Main server functions.
42: */
43:
44: struct clients clients;
45:
1.66 nicm 46: int server_fd;
47: int server_shutdown;
48: struct event server_ev_accept;
1.45 nicm 49:
1.126 nicm 50: struct session *marked_session;
51: struct winlink *marked_winlink;
52: struct window *marked_window;
53: struct window_pane *marked_window_pane;
54: struct layout_cell *marked_layout_cell;
55:
56: int server_create_socket(void);
57: void server_loop(void);
58: int server_should_shutdown(void);
59: void server_send_shutdown(void);
60: void server_accept_callback(int, short, void *);
61: void server_signal_callback(int, short, void *);
62: void server_child_signal(void);
63: void server_child_exited(pid_t, int);
64: void server_child_stopped(pid_t, int);
65:
66: /* Set marked pane. */
67: void
68: server_set_marked(struct session *s, struct winlink *wl, struct window_pane *wp)
69: {
70: marked_session = s;
71: marked_winlink = wl;
72: marked_window = wl->window;
73: marked_window_pane = wp;
74: marked_layout_cell = wp->layout_cell;
75: }
76:
77: /* Clear marked pane. */
78: void
79: server_clear_marked(void)
80: {
81: marked_session = NULL;
82: marked_winlink = NULL;
83: marked_window = NULL;
84: marked_window_pane = NULL;
85: marked_layout_cell = NULL;
86: }
87:
88: /* Is this the marked pane? */
89: int
90: server_is_marked(struct session *s, struct winlink *wl, struct window_pane *wp)
91: {
92: if (s == NULL || wl == NULL || wp == NULL)
93: return (0);
94: if (marked_session != s || marked_winlink != wl)
95: return (0);
96: if (marked_window_pane != wp)
97: return (0);
98: return (server_check_marked());
99: }
100:
101: /* Check if the marked pane is still valid. */
102: int
103: server_check_marked(void)
104: {
105: struct winlink *wl;
106:
107: if (marked_window_pane == NULL)
108: return (0);
109: if (marked_layout_cell != marked_window_pane->layout_cell)
110: return (0);
111:
112: if (!session_alive(marked_session))
113: return (0);
114: RB_FOREACH(wl, winlinks, &marked_session->windows) {
115: if (wl->window == marked_window && wl == marked_winlink)
116: break;
117: }
118: if (wl == NULL)
119: return (0);
120:
121: if (!window_has_pane(marked_window, marked_window_pane))
122: return (0);
123: return (window_pane_visible(marked_window_pane));
124: }
1.45 nicm 125:
1.60 nicm 126: /* Create server socket. */
127: int
128: server_create_socket(void)
1.1 nicm 129: {
1.60 nicm 130: struct sockaddr_un sa;
131: size_t size;
132: mode_t mask;
1.100 nicm 133: int fd;
1.60 nicm 134:
135: memset(&sa, 0, sizeof sa);
136: sa.sun_family = AF_UNIX;
137: size = strlcpy(sa.sun_path, socket_path, sizeof sa.sun_path);
138: if (size >= sizeof sa.sun_path) {
139: errno = ENAMETOOLONG;
1.119 nicm 140: return (-1);
1.60 nicm 141: }
142: unlink(sa.sun_path);
143:
144: if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
1.119 nicm 145: return (-1);
1.60 nicm 146:
1.89 nicm 147: mask = umask(S_IXUSR|S_IXGRP|S_IRWXO);
1.60 nicm 148: if (bind(fd, (struct sockaddr *) &sa, SUN_LEN(&sa)) == -1)
1.119 nicm 149: return (-1);
1.60 nicm 150: umask(mask);
151:
152: if (listen(fd, 16) == -1)
1.119 nicm 153: return (-1);
1.100 nicm 154: setblocking(fd, 0);
1.1 nicm 155:
1.60 nicm 156: return (fd);
157: }
158:
1.1 nicm 159: /* Fork new server. */
160: int
1.138 ! nicm 161: server_start(struct event_base *base, int lockfd, char *lockfile)
1.1 nicm 162: {
1.134 nicm 163: int pair[2];
164: char *cause;
1.1 nicm 165:
166: /* The first client is special and gets a socketpair; create it. */
167: if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pair) != 0)
168: fatal("socketpair failed");
1.115 nicm 169: log_debug("starting server");
1.1 nicm 170:
171: switch (fork()) {
172: case -1:
173: fatal("fork failed");
174: case 0:
175: break;
176: default:
177: close(pair[1]);
178: return (pair[0]);
179: }
180: close(pair[0]);
181:
182: /*
183: * Must daemonise before loading configuration as the PID changes so
184: * $TMUX would be wrong for sessions created in the config file.
185: */
1.16 nicm 186: if (daemon(1, 0) != 0)
1.1 nicm 187: fatal("daemon failed");
188:
1.88 nicm 189: /* event_init() was called in our parent, need to reinit. */
1.125 nicm 190: clear_signals(0);
1.138 ! nicm 191: if (event_reinit(base) != 0)
1.88 nicm 192: fatal("event_reinit failed");
193:
1.16 nicm 194: logfile("server");
195: log_debug("server started, pid %ld", (long) getpid());
196:
1.121 nicm 197: RB_INIT(&windows);
1.102 nicm 198: RB_INIT(&all_window_panes);
1.122 nicm 199: TAILQ_INIT(&clients);
1.97 nicm 200: RB_INIT(&sessions);
1.47 nicm 201: TAILQ_INIT(&session_groups);
1.15 nicm 202: mode_key_init_trees();
1.1 nicm 203: key_bindings_init();
204: utf8_build();
205:
206: start_time = time(NULL);
1.16 nicm 207: log_debug("socket path %s", socket_path);
1.96 nicm 208: setproctitle("server (%s)", socket_path);
1.16 nicm 209:
1.66 nicm 210: server_fd = server_create_socket();
1.119 nicm 211: if (server_fd == -1)
212: fatal("couldn't create socket");
213: server_update_socket();
1.60 nicm 214: server_client_create(pair[1]);
1.103 nicm 215:
216: unlink(lockfile);
1.105 nicm 217: free(lockfile);
1.103 nicm 218: close(lockfd);
1.16 nicm 219:
1.109 nicm 220: cfg_cmd_q = cmdq_new(NULL);
221: cfg_cmd_q->emptyfn = cfg_default_done;
222: cfg_finished = 0;
223: cfg_references = 1;
1.122 nicm 224: cfg_client = TAILQ_FIRST(&clients);
1.111 nicm 225: if (cfg_client != NULL)
226: cfg_client->references++;
1.109 nicm 227:
1.110 nicm 228: if (access(TMUX_CONF, R_OK) == 0) {
1.117 nicm 229: if (load_cfg(TMUX_CONF, cfg_cmd_q, &cause) == -1)
230: cfg_add_cause("%s: %s", TMUX_CONF, cause);
231: } else if (errno != ENOENT)
232: cfg_add_cause("%s: %s", TMUX_CONF, strerror(errno));
1.109 nicm 233: if (cfg_file != NULL) {
1.117 nicm 234: if (load_cfg(cfg_file, cfg_cmd_q, &cause) == -1)
235: cfg_add_cause("%s: %s", cfg_file, cause);
1.109 nicm 236: }
237: cmdq_continue(cfg_cmd_q);
1.129 nicm 238: status_prompt_load_history();
1.66 nicm 239:
1.104 nicm 240: server_add_accept(0);
1.66 nicm 241:
1.88 nicm 242: set_signals(server_signal_callback);
1.66 nicm 243: server_loop();
1.129 nicm 244: status_prompt_save_history();
1.66 nicm 245: exit(0);
1.1 nicm 246: }
247:
248: /* Main server loop. */
1.66 nicm 249: void
250: server_loop(void)
1.1 nicm 251: {
1.66 nicm 252: while (!server_should_shutdown()) {
1.137 nicm 253: log_debug("event dispatch enter");
1.66 nicm 254: event_loop(EVLOOP_ONCE);
1.137 nicm 255: log_debug("event dispatch exit");
1.1 nicm 256:
1.60 nicm 257: server_client_loop();
1.80 nicm 258: }
1.66 nicm 259: }
1.31 nicm 260:
1.112 nicm 261: /* Check if the server should exit (no more clients or sessions). */
1.66 nicm 262: int
263: server_should_shutdown(void)
264: {
1.116 nicm 265: struct client *c;
1.1 nicm 266:
1.94 nicm 267: if (!options_get_number(&global_options, "exit-unattached")) {
1.97 nicm 268: if (!RB_EMPTY(&sessions))
269: return (0);
1.1 nicm 270: }
1.116 nicm 271:
1.122 nicm 272: TAILQ_FOREACH(c, &clients, entry) {
273: if (c->session != NULL)
1.116 nicm 274: return (0);
275: }
276:
277: /*
278: * No attached clients therefore want to exit - flush any waiting
279: * clients but don't actually exit until they've gone.
280: */
281: cmd_wait_for_flush();
1.122 nicm 282: if (!TAILQ_EMPTY(&clients))
283: return (0);
1.116 nicm 284:
1.66 nicm 285: return (1);
1.1 nicm 286: }
287:
1.66 nicm 288: /* Shutdown the server by killing all clients and windows. */
1.1 nicm 289: void
1.66 nicm 290: server_send_shutdown(void)
1.1 nicm 291: {
1.122 nicm 292: struct client *c, *c1;
293: struct session *s, *s1;
1.116 nicm 294:
295: cmd_wait_for_flush();
1.1 nicm 296:
1.122 nicm 297: TAILQ_FOREACH_SAFE(c, &clients, entry, c1) {
298: if (c->flags & (CLIENT_BAD|CLIENT_SUSPENDED))
299: server_client_lost(c);
300: else
301: server_write_client(c, MSG_SHUTDOWN, NULL, 0);
302: c->session = NULL;
1.42 nicm 303: }
304:
1.122 nicm 305: RB_FOREACH_SAFE(s, sessions, &sessions, s1)
1.97 nicm 306: session_destroy(s);
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) {
320: if (!(s->flags & SESSION_UNATTACHED)) {
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;
331: mode = sb.st_mode;
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. */
346: void
347: server_accept_callback(int fd, short events, unused void *data)
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: }
368: if (server_shutdown) {
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 };
383:
384: if (event_initialized(&server_ev_accept))
385: event_del(&server_ev_accept);
386:
387: if (timeout == 0) {
388: event_set(&server_ev_accept,
389: server_fd, EV_READ, server_accept_callback, NULL);
390: event_add(&server_ev_accept, NULL);
391: } else {
392: event_set(&server_ev_accept,
393: server_fd, EV_TIMEOUT, server_accept_callback, NULL);
394: event_add(&server_ev_accept, &tv);
395: }
396: }
397:
1.66 nicm 398: /* Signal handler. */
399: void
400: server_signal_callback(int sig, unused short events, unused void *data)
401: {
1.119 nicm 402: int fd;
1.120 nicm 403:
1.66 nicm 404: switch (sig) {
405: case SIGTERM:
406: server_shutdown = 1;
407: server_send_shutdown();
408: break;
409: case SIGCHLD:
410: server_child_signal();
411: break;
412: case SIGUSR1:
413: event_del(&server_ev_accept);
1.119 nicm 414: fd = server_create_socket();
415: if (fd != -1) {
416: close(server_fd);
417: server_fd = fd;
418: server_update_socket();
419: }
1.104 nicm 420: server_add_accept(0);
1.66 nicm 421: break;
1.1 nicm 422: }
423: }
424:
425: /* Handle SIGCHLD. */
426: void
427: server_child_signal(void)
428: {
1.66 nicm 429: int status;
430: pid_t pid;
1.1 nicm 431:
432: for (;;) {
433: switch (pid = waitpid(WAIT_ANY, &status, WNOHANG|WUNTRACED)) {
434: case -1:
435: if (errno == ECHILD)
436: return;
1.39 nicm 437: fatal("waitpid failed");
1.1 nicm 438: case 0:
439: return;
440: }
1.66 nicm 441: if (WIFSTOPPED(status))
442: server_child_stopped(pid, status);
1.79 nicm 443: else if (WIFEXITED(status) || WIFSIGNALED(status))
1.66 nicm 444: server_child_exited(pid, status);
445: }
446: }
447:
448: /* Handle exited children. */
449: void
450: server_child_exited(pid_t pid, int status)
451: {
1.121 nicm 452: struct window *w, *w1;
1.66 nicm 453: struct window_pane *wp;
454: struct job *job;
455:
1.121 nicm 456: RB_FOREACH_SAFE(w, windows, &windows, w1) {
1.66 nicm 457: TAILQ_FOREACH(wp, &w->panes, entry) {
458: if (wp->pid == pid) {
1.118 nicm 459: wp->status = status;
1.77 nicm 460: server_destroy_pane(wp);
461: break;
1.53 nicm 462: }
463: }
1.80 nicm 464: }
1.1 nicm 465:
1.101 nicm 466: LIST_FOREACH(job, &all_jobs, lentry) {
1.66 nicm 467: if (pid == job->pid) {
1.67 nicm 468: job_died(job, status); /* might free job */
469: break;
1.1 nicm 470: }
1.53 nicm 471: }
472: }
473:
1.66 nicm 474: /* Handle stopped children. */
1.31 nicm 475: void
1.66 nicm 476: server_child_stopped(pid_t pid, int status)
1.31 nicm 477: {
1.66 nicm 478: struct window *w;
479: struct window_pane *wp;
1.31 nicm 480:
1.66 nicm 481: if (WSTOPSIG(status) == SIGTTIN || WSTOPSIG(status) == SIGTTOU)
482: return;
1.31 nicm 483:
1.121 nicm 484: RB_FOREACH(w, windows, &windows) {
1.66 nicm 485: TAILQ_FOREACH(wp, &w->panes, entry) {
486: if (wp->pid == pid) {
487: if (killpg(pid, SIGCONT) != 0)
488: kill(pid, SIGCONT);
489: }
1.1 nicm 490: }
491: }
492: }