tmux.c

   1 /* $OpenBSD$ */
   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/stat.h>
  21 #include <sys/wait.h>
  22
  23 #include <errno.h>
  24 #include <event.h>
  25 #include <paths.h>
  26 #include <pwd.h>
  27 #include <signal.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <syslog.h>
  31 #include <unistd.h>
  32
  33 #include "tmux.h"
  34
  35 #ifdef DEBUG
  36 extern char     *malloc_options;
  37 #endif
  38
  39 char            *cfg_file;
  40 struct options   global_options;        /* server options */
  41 struct options   global_s_options;      /* session options */
  42 struct options   global_w_options;      /* window options */
  43 struct environ   global_environ;
  44
  45 struct event_base *ev_base;
  46
  47 int              debug_level;
  48 time_t           start_time;
  49 char            *socket_path;
  50 int              login_shell;
  51
  52 struct env_data {
  53         char    *path;
  54         pid_t    pid;
  55         u_int    idx;
  56 };
  57
  58 __dead void      usage(void);
  59 void             parse_env(struct env_data *);
  60 char            *makesockpath(const char *);
  61 __dead void      shell_exec(const char *, const char *);
  62
  63 struct imsgbuf  *main_ibuf;
  64
  65 void             main_signal(int, short, unused void *);
  66 void             main_callback(int, short, void *);
  67 void             main_dispatch(const char *);
  68
  69 __dead void
  70 usage(void)
  71 {
  72         fprintf(stderr,
  73             "usage: %s [-28lquv] [-c shell-command] [-f file] [-L socket-name]\n"
  74             "            [-S socket-path] [command [flags]]\n",
  75             __progname);
  76         exit(1);
  77 }
  78
  79 void
  80 logfile(const char *name)
  81 {
  82         char    *path;
  83
  84         log_close();
  85         if (debug_level > 0) {
  86                 xasprintf(&path, "tmux-%s-%ld.log", name, (long) getpid());
  87                 log_open_file(debug_level, path);
  88                 xfree(path);
  89         }
  90 }
  91
  92 const char *
  93 getshell(void)
  94 {
  95         struct passwd   *pw;
  96         const char      *shell;
  97
  98         shell = getenv("SHELL");
  99         if (checkshell(shell))
 100                 return (shell);
 101
 102         pw = getpwuid(getuid());
 103         if (pw != NULL && checkshell(pw->pw_shell))
 104                 return (pw->pw_shell);
 105
 106         return (_PATH_BSHELL);
 107 }
 108
 109 int
 110 checkshell(const char *shell)
 111 {
 112         if (shell == NULL || *shell == '\0' || areshell(shell))
 113                 return (0);
 114         if (access(shell, X_OK) != 0)
 115                 return (0);
 116         return (1);
 117 }
 118
 119 int
 120 areshell(const char *shell)
 121 {
 122         const char      *progname, *ptr;
 123
 124         if ((ptr = strrchr(shell, '/')) != NULL)
 125                 ptr++;
 126         else
 127                 ptr = shell;
 128         progname = __progname;
 129         if (*progname == '-')
 130                 progname++;
 131         if (strcmp(ptr, progname) == 0)
 132                 return (1);
 133         return (0);
 134 }
 135
 136 void
 137 parse_env(struct env_data *data)
 138 {
 139         char            *env, *path_pid, *pid_idx, buf[256];
 140         size_t           len;
 141         const char      *errstr;
 142         long long        ll;
 143
 144         data->pid = -1;
 145         if ((env = getenv("TMUX")) == NULL)
 146                 return;
 147
 148         if ((path_pid = strchr(env, ',')) == NULL || path_pid == env)
 149                 return;
 150         if ((pid_idx = strchr(path_pid + 1, ',')) == NULL)
 151                 return;
 152         if ((pid_idx == path_pid + 1 || pid_idx[1] == '\0'))
 153                 return;
 154
 155         /* path */
 156         len = path_pid - env;
 157         data->path = xmalloc (len + 1);
 158         memcpy(data->path, env, len);
 159         data->path[len] = '\0';
 160
 161         /* pid */
 162         len = pid_idx - path_pid - 1;
 163         if (len > (sizeof buf) - 1)
 164                 return;
 165         memcpy(buf, path_pid + 1, len);
 166         buf[len] = '\0';
 167
 168         ll = strtonum(buf, 0, LONG_MAX, &errstr);
 169         if (errstr != NULL)
 170                 return;
 171         data->pid = ll;
 172
 173         /* idx */
 174         ll = strtonum(pid_idx+1, 0, UINT_MAX, &errstr);
 175         if (errstr != NULL)
 176                 return;
 177         data->idx = ll;
 178 }
 179
 180 char *
 181 makesockpath(const char *label)
 182 {
 183         char            base[MAXPATHLEN], *path;
 184         struct stat     sb;
 185         u_int           uid;
 186
 187         uid = getuid();
 188         xsnprintf(base, MAXPATHLEN, "%s/tmux-%d", _PATH_TMP, uid);
 189
 190         if (mkdir(base, S_IRWXU) != 0 && errno != EEXIST)
 191                 return (NULL);
 192
 193         if (lstat(base, &sb) != 0)
 194                 return (NULL);
 195         if (!S_ISDIR(sb.st_mode)) {
 196                 errno = ENOTDIR;
 197                 return (NULL);
 198         }
 199         if (sb.st_uid != uid || (sb.st_mode & (S_IRWXG|S_IRWXO)) != 0) {
 200                 errno = EACCES;
 201                 return (NULL);
 202         }
 203
 204         xasprintf(&path, "%s/%s", base, label);
 205         return (path);
 206 }
 207
 208 __dead void
 209 shell_exec(const char *shell, const char *shellcmd)
 210 {
 211         const char      *shellname, *ptr;
 212         char            *argv0;
 213
 214         ptr = strrchr(shell, '/');
 215         if (ptr != NULL && *(ptr + 1) != '\0')
 216                 shellname = ptr + 1;
 217         else
 218                 shellname = shell;
 219         if (login_shell)
 220                 xasprintf(&argv0, "-%s", shellname);
 221         else
 222                 xasprintf(&argv0, "%s", shellname);
 223         setenv("SHELL", shell, 1);
 224
 225         execl(shell, argv0, "-c", shellcmd, (char *) NULL);
 226         fatal("execl failed");
 227 }
 228
 229 int
 230 main(int argc, char **argv)
 231 {
 232         struct cmd_list         *cmdlist;
 233         struct cmd              *cmd;
 234         enum msgtype             msg;
 235         struct passwd           *pw;
 236         struct options          *oo, *so, *wo;
 237         struct keylist          *keylist;
 238         struct env_data          envdata;
 239         struct msg_command_data  cmddata;
 240         char                    *s, *shellcmd, *path, *label, *home, *cause;
 241         char                   **var;
 242         void                    *buf;
 243         size_t                   len;
 244         int                      opt, flags, quiet = 0, cmdflags = 0;
 245         short                    events;
 246
 247 #ifdef DEBUG
 248         malloc_options = (char *) "AFGJPX";
 249 #endif
 250
 251         flags = 0;
 252         shellcmd = label = path = NULL;
 253         envdata.path = NULL;
 254         login_shell = (**argv == '-');
 255         while ((opt = getopt(argc, argv, "28c:df:lL:qS:uUv")) != -1) {
 256                 switch (opt) {
 257                 case '2':
 258                         flags |= IDENTIFY_256COLOURS;
 259                         flags &= ~IDENTIFY_88COLOURS;
 260                         break;
 261                 case '8':
 262                         flags |= IDENTIFY_88COLOURS;
 263                         flags &= ~IDENTIFY_256COLOURS;
 264                         break;
 265                 case 'c':
 266                         if (shellcmd != NULL)
 267                                 xfree(shellcmd);
 268                         shellcmd = xstrdup(optarg);
 269                         break;
 270                 case 'f':
 271                         if (cfg_file != NULL)
 272                                 xfree(cfg_file);
 273                         cfg_file = xstrdup(optarg);
 274                         break;
 275                 case 'l':
 276                         login_shell = 1;
 277                         break;
 278                 case 'L':
 279                         if (label != NULL)
 280                                 xfree(label);
 281                         label = xstrdup(optarg);
 282                         break;
 283                 case 'q':
 284                         quiet = 1;
 285                         break;
 286                 case 'S':
 287                         if (path != NULL)
 288                                 xfree(path);
 289                         path = xstrdup(optarg);
 290                         break;
 291                 case 'u':
 292                         flags |= IDENTIFY_UTF8;
 293                         break;
 294                 case 'v':
 295                         debug_level++;
 296                         break;
 297                 default:
 298                         usage();
 299                 }
 300         }
 301         argc -= optind;
 302         argv += optind;
 303
 304         if (shellcmd != NULL && argc != 0)
 305                 usage();
 306
 307         log_open_tty(debug_level);
 308
 309         if (!(flags & IDENTIFY_UTF8)) {
 310                 /*
 311                  * If the user has set whichever of LC_ALL, LC_CTYPE or LANG
 312                  * exist (in that order) to contain UTF-8, it is a safe
 313                  * assumption that either they are using a UTF-8 terminal, or
 314                  * if not they know that output from UTF-8-capable programs may
 315                  * be wrong.
 316                  */
 317                 if ((s = getenv("LC_ALL")) == NULL) {
 318                         if ((s = getenv("LC_CTYPE")) == NULL)
 319                                 s = getenv("LANG");
 320                 }
 321                 if (s != NULL && (strcasestr(s, "UTF-8") != NULL ||
 322                     strcasestr(s, "UTF8") != NULL))
 323                         flags |= IDENTIFY_UTF8;
 324         }
 325
 326         environ_init(&global_environ);
 327         for (var = environ; *var != NULL; var++)
 328                 environ_put(&global_environ, *var);
 329
 330         options_init(&global_options, NULL);
 331         oo = &global_options;
 332         options_set_number(oo, "quiet", quiet);
 333         options_set_number(oo, "escape-time", 500);
 334
 335         options_init(&global_s_options, NULL);
 336         so = &global_s_options;
 337         options_set_number(so, "base-index", 0);
 338         options_set_number(so, "bell-action", BELL_ANY);
 339         options_set_number(so, "buffer-limit", 9);
 340         options_set_string(so, "default-command", "%s", "");
 341         options_set_string(so, "default-path", "%s", "");
 342         options_set_string(so, "default-shell", "%s", getshell());
 343         options_set_string(so, "default-terminal", "screen");
 344         options_set_number(so, "detach-on-destroy", 1);
 345         options_set_number(so, "display-panes-active-colour", 1);
 346         options_set_number(so, "display-panes-colour", 4);
 347         options_set_number(so, "display-panes-time", 1000);
 348         options_set_number(so, "display-time", 750);
 349         options_set_number(so, "history-limit", 2000);
 350         options_set_number(so, "lock-after-time", 0);
 351         options_set_string(so, "lock-command", "lock -np");
 352         options_set_number(so, "lock-server", 1);
 353         options_set_number(so, "message-attr", 0);
 354         options_set_number(so, "message-bg", 3);
 355         options_set_number(so, "message-fg", 0);
 356         options_set_number(so, "message-limit", 20);
 357         options_set_number(so, "mouse-select-pane", 0);
 358         options_set_number(so, "pane-active-border-bg", 8);
 359         options_set_number(so, "pane-active-border-fg", 2);
 360         options_set_number(so, "pane-border-bg", 8);
 361         options_set_number(so, "pane-border-fg", 8);
 362         options_set_number(so, "repeat-time", 500);
 363         options_set_number(so, "set-remain-on-exit", 0);
 364         options_set_number(so, "set-titles", 0);
 365         options_set_string(so, "set-titles-string", "#S:#I:#W - \"#T\"");
 366         options_set_number(so, "status", 1);
 367         options_set_number(so, "status-attr", 0);
 368         options_set_number(so, "status-bg", 2);
 369         options_set_number(so, "status-fg", 0);
 370         options_set_number(so, "status-interval", 15);
 371         options_set_number(so, "status-justify", 0);
 372         options_set_number(so, "status-keys", MODEKEY_EMACS);
 373         options_set_string(so, "status-left", "[#S]");
 374         options_set_number(so, "status-left-attr", 0);
 375         options_set_number(so, "status-left-bg", 8);
 376         options_set_number(so, "status-left-fg", 8);
 377         options_set_number(so, "status-left-length", 10);
 378         options_set_string(so, "status-right", "\"#22T\" %%H:%%M %%d-%%b-%%y");
 379         options_set_number(so, "status-right-attr", 0);
 380         options_set_number(so, "status-right-bg", 8);
 381         options_set_number(so, "status-right-fg", 8);
 382         options_set_number(so, "status-right-length", 40);
 383         options_set_string(so, "terminal-overrides",
 384             "*88col*:colors=88,*256col*:colors=256");
 385         options_set_string(so, "update-environment", "DISPLAY "
 386             "WINDOWID SSH_ASKPASS SSH_AUTH_SOCK SSH_AGENT_PID SSH_CONNECTION");
 387         options_set_number(so, "visual-activity", 0);
 388         options_set_number(so, "visual-bell", 0);
 389         options_set_number(so, "visual-content", 0);
 390
 391         keylist = xmalloc(sizeof *keylist);
 392         ARRAY_INIT(keylist);
 393         ARRAY_ADD(keylist, '\002');
 394         options_set_data(so, "prefix", keylist, xfree);
 395
 396         options_init(&global_w_options, NULL);
 397         wo = &global_w_options;
 398         options_set_number(wo, "aggressive-resize", 0);
 399         options_set_number(wo, "alternate-screen", 1);
 400         options_set_number(wo, "automatic-rename", 1);
 401         options_set_number(wo, "clock-mode-colour", 4);
 402         options_set_number(wo, "clock-mode-style", 1);
 403         options_set_number(wo, "force-height", 0);
 404         options_set_number(wo, "force-width", 0);
 405         options_set_number(wo, "main-pane-height", 24);
 406         options_set_number(wo, "main-pane-width", 81);
 407         options_set_number(wo, "mode-attr", 0);
 408         options_set_number(wo, "mode-bg", 3);
 409         options_set_number(wo, "mode-fg", 0);
 410         options_set_number(wo, "mode-keys", MODEKEY_EMACS);
 411         options_set_number(wo, "mode-mouse", 0);
 412         options_set_number(wo, "monitor-activity", 0);
 413         options_set_string(wo, "monitor-content", "%s", "");
 414         options_set_number(wo, "window-status-attr", 0);
 415         options_set_number(wo, "window-status-bg", 8);
 416         options_set_number(wo, "window-status-current-attr", 0);
 417         options_set_number(wo, "window-status-current-bg", 8);
 418         options_set_number(wo, "window-status-current-fg", 8);
 419         options_set_number(wo, "window-status-fg", 8);
 420         options_set_number(wo, "window-status-alert-attr", GRID_ATTR_REVERSE);
 421         options_set_number(wo, "window-status-alert-bg", 8);
 422         options_set_number(wo, "window-status-alert-fg", 8);
 423         options_set_string(wo, "window-status-format", "#I:#W#F");
 424         options_set_string(wo, "window-status-current-format", "#I:#W#F");
 425         options_set_string(wo, "word-separators", " -_@");
 426         options_set_number(wo, "xterm-keys", 0);
 427         options_set_number(wo, "remain-on-exit", 0);
 428         options_set_number(wo, "synchronize-panes", 0);
 429
 430         if (flags & IDENTIFY_UTF8) {
 431                 options_set_number(so, "status-utf8", 1);
 432                 options_set_number(wo, "utf8", 1);
 433         } else {
 434                 options_set_number(so, "status-utf8", 0);
 435                 options_set_number(wo, "utf8", 0);
 436         }
 437
 438         if (cfg_file == NULL) {
 439                 home = getenv("HOME");
 440                 if (home == NULL || *home == '\0') {
 441                         pw = getpwuid(getuid());
 442                         if (pw != NULL)
 443                                 home = pw->pw_dir;
 444                 }
 445                 xasprintf(&cfg_file, "%s/%s", home, DEFAULT_CFG);
 446                 if (access(cfg_file, R_OK) != 0 && errno == ENOENT) {
 447                         xfree(cfg_file);
 448                         cfg_file = NULL;
 449                 }
 450         }
 451
 452         /*
 453          * Figure out the socket path. If specified on the command-line with
 454          * -S or -L, use it, otherwise try $TMUX or assume -L default.
 455          */
 456         parse_env(&envdata);
 457         if (path == NULL) {
 458                 /* No -L. Try $TMUX, or default. */
 459                 if (label == NULL) {
 460                         path = envdata.path;
 461                         if (path == NULL)
 462                                 label = xstrdup("default");
 463                 }
 464
 465                 /* -L or default set. */
 466                 if (label != NULL) {
 467                         if ((path = makesockpath(label)) == NULL) {
 468                                 log_warn("can't create socket");
 469                                 exit(1);
 470                         }
 471                 }
 472         }
 473         if (label != NULL)
 474                 xfree(label);
 475
 476         if (shellcmd != NULL) {
 477                 msg = MSG_SHELL;
 478                 buf = NULL;
 479                 len = 0;
 480         } else {
 481                 cmddata.pid = envdata.pid;
 482                 cmddata.idx = envdata.idx;
 483
 484                 /* Prepare command for server. */
 485                 cmddata.argc = argc;
 486                 if (cmd_pack_argv(
 487                     argc, argv, cmddata.argv, sizeof cmddata.argv) != 0) {
 488                         log_warnx("command too long");
 489                         exit(1);
 490                 }
 491
 492                 msg = MSG_COMMAND;
 493                 buf = &cmddata;
 494                 len = sizeof cmddata;
 495         }
 496
 497         if (shellcmd != NULL)
 498                 cmdflags |= CMD_STARTSERVER;
 499         else if (argc == 0)     /* new-session is the default */
 500                 cmdflags |= CMD_STARTSERVER|CMD_SENDENVIRON|CMD_CANTNEST;
 501         else {
 502                 /*
 503                  * It sucks parsing the command string twice (in client and
 504                  * later in server) but it is necessary to get the start server
 505                  * flag.
 506                  */
 507                 if ((cmdlist = cmd_list_parse(argc, argv, &cause)) == NULL) {
 508                         log_warnx("%s", cause);
 509                         exit(1);
 510                 }
 511                 cmdflags &= ~CMD_STARTSERVER;
 512                 TAILQ_FOREACH(cmd, &cmdlist->list, qentry) {
 513                         if (cmd->entry->flags & CMD_STARTSERVER)
 514                                 cmdflags |= CMD_STARTSERVER;
 515                         if (cmd->entry->flags & CMD_SENDENVIRON)
 516                                 cmdflags |= CMD_SENDENVIRON;
 517                         if (cmd->entry->flags & CMD_CANTNEST)
 518                                 cmdflags |= CMD_CANTNEST;
 519                 }
 520                 cmd_list_free(cmdlist);
 521         }
 522
 523         /*
 524          * Check if this could be a nested session, if the command can't nest:
 525          * if the socket path matches $TMUX, this is probably the same server.
 526          */
 527         if (shellcmd == NULL && envdata.path != NULL &&
 528             cmdflags & CMD_CANTNEST &&
 529             (path == envdata.path || strcmp(path, envdata.path) == 0)) {
 530                 log_warnx("sessions should be nested with care. "
 531                     "unset $TMUX to force.");
 532                 exit(1);
 533         }
 534
 535         ev_base = event_init();
 536         set_signals(main_signal);
 537
 538         /* Initialise the client socket/start the server. */
 539         if ((main_ibuf = client_init(path, cmdflags, flags)) == NULL)
 540                 exit(1);
 541         xfree(path);
 542
 543         imsg_compose(main_ibuf, msg, PROTOCOL_VERSION, -1, -1, buf, len);
 544
 545         events = EV_READ;
 546         if (main_ibuf->w.queued > 0)
 547                 events |= EV_WRITE;
 548         event_once(main_ibuf->fd, events, main_callback, shellcmd, NULL);
 549
 550         event_dispatch();
 551
 552         clear_signals();
 553
 554         client_main();  /* doesn't return */
 555 }
 556
 557 /* ARGSUSED */
 558 void
 559 main_signal(int sig, unused short events, unused void *data)
 560 {
 561         int     status;
 562
 563         switch (sig) {
 564         case SIGTERM:
 565                 exit(1);
 566         case SIGCHLD:
 567                 waitpid(WAIT_ANY, &status, WNOHANG);
 568                 break;
 569         }
 570 }
 571
 572 /* ARGSUSED */
 573 void
 574 main_callback(unused int fd, short events, void *data)
 575 {
 576         char    *shellcmd = data;
 577
 578         if (events & EV_READ)
 579                 main_dispatch(shellcmd);
 580
 581         if (events & EV_WRITE) {
 582                 if (msgbuf_write(&main_ibuf->w) < 0)
 583                         fatalx("msgbuf_write failed");
 584         }
 585
 586         events = EV_READ;
 587         if (main_ibuf->w.queued > 0)
 588                 events |= EV_WRITE;
 589         event_once(main_ibuf->fd, events, main_callback, shellcmd, NULL);
 590 }
 591
 592 void
 593 main_dispatch(const char *shellcmd)
 594 {
 595         struct imsg             imsg;
 596         ssize_t                 n, datalen;
 597         struct msg_shell_data   shelldata;
 598         struct msg_exit_data    exitdata;
 599
 600         if ((n = imsg_read(main_ibuf)) == -1 || n == 0)
 601                 fatalx("imsg_read failed");
 602
 603         for (;;) {
 604                 if ((n = imsg_get(main_ibuf, &imsg)) == -1)
 605                         fatalx("imsg_get failed");
 606                 if (n == 0)
 607                         return;
 608                 datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
 609
 610                 switch (imsg.hdr.type) {
 611                 case MSG_EXIT:
 612                 case MSG_SHUTDOWN:
 613                         if (datalen != sizeof exitdata) {
 614                                 if (datalen != 0)
 615                                         fatalx("bad MSG_EXIT size");
 616                                 exit(0);
 617                         }
 618                         memcpy(&exitdata, imsg.data, sizeof exitdata);
 619                         exit(exitdata.retcode);
 620                 case MSG_READY:
 621                         if (datalen != 0)
 622                                 fatalx("bad MSG_READY size");
 623
 624                         event_loopexit(NULL);   /* move to client_main() */
 625                         break;
 626                 case MSG_VERSION:
 627                         if (datalen != 0)
 628                                 fatalx("bad MSG_VERSION size");
 629
 630                         log_warnx("protocol version mismatch (client %u, "
 631                             "server %u)", PROTOCOL_VERSION, imsg.hdr.peerid);
 632                         exit(1);
 633                 case MSG_SHELL:
 634                         if (datalen != sizeof shelldata)
 635                                 fatalx("bad MSG_SHELL size");
 636                         memcpy(&shelldata, imsg.data, sizeof shelldata);
 637                         shelldata.shell[(sizeof shelldata.shell) - 1] = '\0';
 638
 639                         clear_signals();
 640
 641                         shell_exec(shelldata.shell, shellcmd);
 642                 default:
 643                         fatalx("unexpected message");
 644                 }
 645
 646                 imsg_free(&imsg);
 647         }
 648 }