1 /* $OpenBSD$ */ 2 3 /* 4 * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com> 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> 27 #include <fcntl.h> 28 #include <signal.h> 29 #include <stdio.h> 30 #include <stdlib.h> 31 #include <string.h> 32 #include <termios.h> 33 #include <time.h> 34 #include <unistd.h> 35 36 #include "tmux.h" 37 38 /* 39 * Main server functions. 40 */ 41 42 struct clients clients; 43 44 struct tmuxproc *server_proc; 45 static int server_fd = -1; 46 static uint64_t server_client_flags; 47 static int server_exit; 48 static struct event server_ev_accept; 49 static struct event server_ev_tidy; 50 51 struct cmd_find_state marked_pane; 52 53 static u_int message_next; 54 struct message_list message_log; 55 56 static int server_loop(void); 57 static void server_send_exit(void); 58 static void server_accept(int, short, void *); 59 static void server_signal(int); 60 static void server_child_signal(void); 61 static void server_child_exited(pid_t, int); 62 static void server_child_stopped(pid_t, int); 63 64 /* Set marked pane. */ 65 void 66 server_set_marked(struct session *s, struct winlink *wl, struct window_pane *wp) 67 { 68 cmd_find_clear_state(&marked_pane, 0); 69 marked_pane.s = s; 70 marked_pane.wl = wl; 71 marked_pane.w = wl->window; 72 marked_pane.wp = wp; 73 } 74 75 /* Clear marked pane. */ 76 void 77 server_clear_marked(void) 78 { 79 cmd_find_clear_state(&marked_pane, 0); 80 } 81 82 /* Is this the marked pane? */ 83 int 84 server_is_marked(struct session *s, struct winlink *wl, struct window_pane *wp) 85 { 86 if (s == NULL || wl == NULL || wp == NULL) 87 return (0); 88 if (marked_pane.s != s || marked_pane.wl != wl) 89 return (0); 90 if (marked_pane.wp != wp) 91 return (0); 92 return (server_check_marked()); 93 } 94 95 /* Check if the marked pane is still valid. */ 96 int 97 server_check_marked(void) 98 { 99 return (cmd_find_valid_state(&marked_pane)); 100 } 101 102 /* Create server socket. */ 103 static int 104 server_create_socket(int flags, char **cause) 105 { 106 struct sockaddr_un sa; 107 size_t size; 108 mode_t mask; 109 int fd, saved_errno; 110 111 memset(&sa, 0, sizeof sa); 112 sa.sun_family = AF_UNIX; 113 size = strlcpy(sa.sun_path, socket_path, sizeof sa.sun_path); 114 if (size >= sizeof sa.sun_path) { 115 errno = ENAMETOOLONG; 116 goto fail; 117 } 118 unlink(sa.sun_path); 119 120 if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) 121 goto fail; 122 123 if (flags & CLIENT_DEFAULTSOCKET) 124 mask = umask(S_IXUSR|S_IXGRP|S_IRWXO); 125 else 126 mask = umask(S_IXUSR|S_IRWXG|S_IRWXO); 127 if (bind(fd, (struct sockaddr *)&sa, sizeof sa) == -1) { 128 saved_errno = errno; 129 close(fd); 130 errno = saved_errno; 131 goto fail; 132 } 133 umask(mask); 134 135 if (listen(fd, 128) == -1) { 136 saved_errno = errno; 137 close(fd); 138 errno = saved_errno; 139 goto fail; 140 } 141 setblocking(fd, 0); 142 143 return (fd); 144 145 fail: 146 if (cause != NULL) { 147 xasprintf(cause, "error creating %s (%s)", socket_path, 148 strerror(errno)); 149 } 150 return (-1); 151 } 152 153 /* Tidy up every hour. */ 154 static void 155 server_tidy_event(__unused int fd, __unused short events, __unused void *data) 156 { 157 struct timeval tv = { .tv_sec = 3600 }; 158 uint64_t t = get_timer(); 159 160 format_tidy_jobs(); 161 162 #ifdef HAVE_MALLOC_TRIM 163 malloc_trim(0); 164 #endif 165 166 log_debug("%s: took %ju milliseconds", __func__, (uintmax_t)get_timer() - t); 167 evtimer_add(&server_ev_tidy, &tv); 168 } 169 170 /* Fork new server. */ 171 int 172 server_start(struct tmuxproc *client, int flags, struct event_base *base, 173 int lockfd, char *lockfile) 174 { 175 int fd; 176 sigset_t set, oldset; 177 struct client *c = NULL; 178 char *cause = NULL; 179 struct timeval tv = { .tv_sec = 3600 }; 180 181 sigfillset(&set); 182 sigprocmask(SIG_BLOCK, &set, &oldset); 183 184 if (~flags & CLIENT_NOFORK) { 185 if (proc_fork_and_daemon(&fd) != 0) { 186 sigprocmask(SIG_SETMASK, &oldset, NULL); 187 return (fd); 188 } 189 } 190 proc_clear_signals(client, 0); 191 server_client_flags = flags; 192 193 if (event_reinit(base) != 0) 194 fatalx("event_reinit failed"); 195 server_proc = proc_start("server"); 196 197 proc_set_signals(server_proc, server_signal); 198 sigprocmask(SIG_SETMASK, &oldset, NULL); 199 200 if (log_get_level() > 1) 201 tty_create_log(); 202 if (pledge("stdio rpath wpath cpath fattr unix getpw recvfd proc exec " 203 "tty ps", NULL) != 0) 204 fatal("pledge failed"); 205 206 input_key_build(); 207 RB_INIT(&windows); 208 RB_INIT(&all_window_panes); 209 TAILQ_INIT(&clients); 210 RB_INIT(&sessions); 211 key_bindings_init(); 212 TAILQ_INIT(&message_log); 213 214 gettimeofday(&start_time, NULL); 215 216 server_fd = server_create_socket(flags, &cause); 217 if (server_fd != -1) 218 server_update_socket(); 219 if (~flags & CLIENT_NOFORK) 220 c = server_client_create(fd); 221 else 222 options_set_number(global_options, "exit-empty", 0); 223 224 if (lockfd >= 0) { 225 unlink(lockfile); 226 free(lockfile); 227 close(lockfd); 228 } 229 230 if (cause != NULL) { 231 if (c != NULL) { 232 cmdq_append(c, cmdq_get_error(cause)); 233 c->flags |= CLIENT_EXIT; 234 } 235 free(cause); 236 } 237 238 evtimer_set(&server_ev_tidy, server_tidy_event, NULL); 239 evtimer_add(&server_ev_tidy, &tv); 240 241 server_add_accept(0); 242 proc_loop(server_proc, server_loop); 243 244 job_kill_all(); 245 status_prompt_save_history(); 246 247 exit(0); 248 } 249 250 /* Server loop callback. */ 251 static int 252 server_loop(void) 253 { 254 struct client *c; 255 u_int items; 256 257 do { 258 items = cmdq_next(NULL); 259 TAILQ_FOREACH(c, &clients, entry) { 260 if (c->flags & CLIENT_IDENTIFIED) 261 items += cmdq_next(c); 262 } 263 } while (items != 0); 264 265 server_client_loop(); 266 267 if (!options_get_number(global_options, "exit-empty") && !server_exit) 268 return (0); 269 270 if (!options_get_number(global_options, "exit-unattached")) { 271 if (!RB_EMPTY(&sessions)) 272 return (0); 273 } 274 275 TAILQ_FOREACH(c, &clients, entry) { 276 if (c->session != NULL) 277 return (0); 278 } 279 280 /* 281 * No attached clients therefore want to exit - flush any waiting 282 * clients but don't actually exit until they've gone. 283 */ 284 cmd_wait_for_flush(); 285 if (!TAILQ_EMPTY(&clients)) 286 return (0); 287 288 if (job_still_running()) 289 return (0); 290 291 return (1); 292 } 293 294 /* Exit the server by killing all clients and windows. */ 295 static void 296 server_send_exit(void) 297 { 298 struct client *c, *c1; 299 struct session *s, *s1; 300 301 cmd_wait_for_flush(); 302 303 TAILQ_FOREACH_SAFE(c, &clients, entry, c1) { 304 if (c->flags & CLIENT_SUSPENDED) 305 server_client_lost(c); 306 else { 307 c->flags |= CLIENT_EXIT; 308 c->exit_type = CLIENT_EXIT_SHUTDOWN; 309 } 310 c->session = NULL; 311 } 312 313 RB_FOREACH_SAFE(s, sessions, &sessions, s1) 314 session_destroy(s, 1, __func__); 315 } 316 317 /* Update socket execute permissions based on whether sessions are attached. */ 318 void 319 server_update_socket(void) 320 { 321 struct session *s; 322 static int last = -1; 323 int n, mode; 324 struct stat sb; 325 326 n = 0; 327 RB_FOREACH(s, sessions, &sessions) { 328 if (s->attached != 0) { 329 n++; 330 break; 331 } 332 } 333 334 if (n != last) { 335 last = n; 336 337 if (stat(socket_path, &sb) != 0) 338 return; 339 mode = sb.st_mode & ACCESSPERMS; 340 if (n != 0) { 341 if (mode & S_IRUSR) 342 mode |= S_IXUSR; 343 if (mode & S_IRGRP) 344 mode |= S_IXGRP; 345 if (mode & S_IROTH) 346 mode |= S_IXOTH; 347 } else 348 mode &= ~(S_IXUSR|S_IXGRP|S_IXOTH); 349 chmod(socket_path, mode); 350 } 351 } 352 353 /* Callback for server socket. */ 354 static void 355 server_accept(int fd, short events, __unused void *data) 356 { 357 struct sockaddr_storage sa; 358 socklen_t slen = sizeof sa; 359 int newfd; 360 361 server_add_accept(0); 362 if (!(events & EV_READ)) 363 return; 364 365 newfd = accept(fd, (struct sockaddr *) &sa, &slen); 366 if (newfd == -1) { 367 if (errno == EAGAIN || errno == EINTR || errno == ECONNABORTED) 368 return; 369 if (errno == ENFILE || errno == EMFILE) { 370 /* Delete and don't try again for 1 second. */ 371 server_add_accept(1); 372 return; 373 } 374 fatal("accept failed"); 375 } 376 if (server_exit) { 377 close(newfd); 378 return; 379 } 380 server_client_create(newfd); 381 } 382 383 /* 384 * Add accept event. If timeout is nonzero, add as a timeout instead of a read 385 * event - used to backoff when running out of file descriptors. 386 */ 387 void 388 server_add_accept(int timeout) 389 { 390 struct timeval tv = { timeout, 0 }; 391 392 if (server_fd == -1) 393 return; 394 395 if (event_initialized(&server_ev_accept)) 396 event_del(&server_ev_accept); 397 398 if (timeout == 0) { 399 event_set(&server_ev_accept, server_fd, EV_READ, server_accept, 400 NULL); 401 event_add(&server_ev_accept, NULL); 402 } else { 403 event_set(&server_ev_accept, server_fd, EV_TIMEOUT, 404 server_accept, NULL); 405 event_add(&server_ev_accept, &tv); 406 } 407 } 408 409 /* Signal handler. */ 410 static void 411 server_signal(int sig) 412 { 413 int fd; 414 415 log_debug("%s: %s", __func__, strsignal(sig)); 416 switch (sig) { 417 case SIGINT: 418 case SIGTERM: 419 server_exit = 1; 420 server_send_exit(); 421 break; 422 case SIGCHLD: 423 server_child_signal(); 424 break; 425 case SIGUSR1: 426 event_del(&server_ev_accept); 427 fd = server_create_socket(server_client_flags, NULL); 428 if (fd != -1) { 429 close(server_fd); 430 server_fd = fd; 431 server_update_socket(); 432 } 433 server_add_accept(0); 434 break; 435 case SIGUSR2: 436 proc_toggle_log(server_proc); 437 break; 438 } 439 } 440 441 /* Handle SIGCHLD. */ 442 static void 443 server_child_signal(void) 444 { 445 int status; 446 pid_t pid; 447 448 for (;;) { 449 switch (pid = waitpid(WAIT_ANY, &status, WNOHANG|WUNTRACED)) { 450 case -1: 451 if (errno == ECHILD) 452 return; 453 fatal("waitpid failed"); 454 case 0: 455 return; 456 } 457 if (WIFSTOPPED(status)) 458 server_child_stopped(pid, status); 459 else if (WIFEXITED(status) || WIFSIGNALED(status)) 460 server_child_exited(pid, status); 461 } 462 } 463 464 /* Handle exited children. */ 465 static void 466 server_child_exited(pid_t pid, int status) 467 { 468 struct window *w, *w1; 469 struct window_pane *wp; 470 471 RB_FOREACH_SAFE(w, windows, &windows, w1) { 472 TAILQ_FOREACH(wp, &w->panes, entry) { 473 if (wp->pid == pid) { 474 wp->status = status; 475 wp->flags |= PANE_STATUSREADY; 476 477 log_debug("%%%u exited", wp->id); 478 wp->flags |= PANE_EXITED; 479 480 if (window_pane_destroy_ready(wp)) 481 server_destroy_pane(wp, 1); 482 break; 483 } 484 } 485 } 486 job_check_died(pid, status); 487 } 488 489 /* Handle stopped children. */ 490 static void 491 server_child_stopped(pid_t pid, int status) 492 { 493 struct window *w; 494 struct window_pane *wp; 495 496 if (WSTOPSIG(status) == SIGTTIN || WSTOPSIG(status) == SIGTTOU) 497 return; 498 499 RB_FOREACH(w, windows, &windows) { 500 TAILQ_FOREACH(wp, &w->panes, entry) { 501 if (wp->pid == pid) { 502 if (killpg(pid, SIGCONT) != 0) 503 kill(pid, SIGCONT); 504 } 505 } 506 } 507 job_check_died(pid, status); 508 } 509 510 /* Add to message log. */ 511 void 512 server_add_message(const char *fmt, ...) 513 { 514 struct message_entry *msg, *msg1; 515 char *s; 516 va_list ap; 517 u_int limit; 518 519 va_start(ap, fmt); 520 xvasprintf(&s, fmt, ap); 521 va_end(ap); 522 523 log_debug("message: %s", s); 524 525 msg = xcalloc(1, sizeof *msg); 526 gettimeofday(&msg->msg_time, NULL); 527 msg->msg_num = message_next++; 528 msg->msg = s; 529 TAILQ_INSERT_TAIL(&message_log, msg, entry); 530 531 limit = options_get_number(global_options, "message-limit"); 532 TAILQ_FOREACH_SAFE(msg, &message_log, entry, msg1) { 533 if (msg->msg_num + limit >= message_next) 534 break; 535 free(msg->msg); 536 TAILQ_REMOVE(&message_log, msg, entry); 537 free(msg); 538 } 539 } 540