tmux.c revision 1.207
1/* $OpenBSD: tmux.c,v 1.207 2021/06/10 07:52:29 nicm Exp $ */ 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/stat.h> 21#include <sys/utsname.h> 22 23#include <err.h> 24#include <errno.h> 25#include <event.h> 26#include <fcntl.h> 27#include <langinfo.h> 28#include <locale.h> 29#include <paths.h> 30#include <pwd.h> 31#include <signal.h> 32#include <stdlib.h> 33#include <string.h> 34#include <time.h> 35#include <unistd.h> 36#include <util.h> 37 38#include "tmux.h" 39 40struct options *global_options; /* server options */ 41struct options *global_s_options; /* session options */ 42struct options *global_w_options; /* window options */ 43struct environ *global_environ; 44 45struct timeval start_time; 46const char *socket_path; 47int ptm_fd = -1; 48const char *shell_command; 49 50static __dead void usage(void); 51static char *make_label(const char *, char **); 52 53static int areshell(const char *); 54static const char *getshell(void); 55 56static __dead void 57usage(void) 58{ 59 fprintf(stderr, 60 "usage: %s [-2CDlNuvV] [-c shell-command] [-f file] [-L socket-name]\n" 61 " [-S socket-path] [-T features] [command [flags]]\n", 62 getprogname()); 63 exit(1); 64} 65 66static const char * 67getshell(void) 68{ 69 struct passwd *pw; 70 const char *shell; 71 72 shell = getenv("SHELL"); 73 if (checkshell(shell)) 74 return (shell); 75 76 pw = getpwuid(getuid()); 77 if (pw != NULL && checkshell(pw->pw_shell)) 78 return (pw->pw_shell); 79 80 return (_PATH_BSHELL); 81} 82 83int 84checkshell(const char *shell) 85{ 86 if (shell == NULL || *shell != '/') 87 return (0); 88 if (areshell(shell)) 89 return (0); 90 if (access(shell, X_OK) != 0) 91 return (0); 92 return (1); 93} 94 95static int 96areshell(const char *shell) 97{ 98 const char *progname, *ptr; 99 100 if ((ptr = strrchr(shell, '/')) != NULL) 101 ptr++; 102 else 103 ptr = shell; 104 progname = getprogname(); 105 if (*progname == '-') 106 progname++; 107 if (strcmp(ptr, progname) == 0) 108 return (1); 109 return (0); 110} 111 112static char * 113expand_path(const char *path, const char *home) 114{ 115 char *expanded, *name; 116 const char *end; 117 struct environ_entry *value; 118 119 if (strncmp(path, "~/", 2) == 0) { 120 if (home == NULL) 121 return (NULL); 122 xasprintf(&expanded, "%s%s", home, path + 1); 123 return (expanded); 124 } 125 126 if (*path == '$') { 127 end = strchr(path, '/'); 128 if (end == NULL) 129 name = xstrdup(path + 1); 130 else 131 name = xstrndup(path + 1, end - path - 1); 132 value = environ_find(global_environ, name); 133 free(name); 134 if (value == NULL) 135 return (NULL); 136 if (end == NULL) 137 end = ""; 138 xasprintf(&expanded, "%s%s", value->value, end); 139 return (expanded); 140 } 141 142 return (xstrdup(path)); 143} 144 145static void 146expand_paths(const char *s, char ***paths, u_int *n, int ignore_errors) 147{ 148 const char *home = find_home(); 149 char *copy, *next, *tmp, resolved[PATH_MAX], *expanded; 150 char *path; 151 u_int i; 152 153 *paths = NULL; 154 *n = 0; 155 156 copy = tmp = xstrdup(s); 157 while ((next = strsep(&tmp, ":")) != NULL) { 158 expanded = expand_path(next, home); 159 if (expanded == NULL) { 160 log_debug("%s: invalid path: %s", __func__, next); 161 continue; 162 } 163 if (realpath(expanded, resolved) == NULL) { 164 log_debug("%s: realpath(\"%s\") failed: %s", __func__, 165 expanded, strerror(errno)); 166 if (ignore_errors) { 167 free(expanded); 168 continue; 169 } 170 path = expanded; 171 } else { 172 path = xstrdup(resolved); 173 free(expanded); 174 } 175 for (i = 0; i < *n; i++) { 176 if (strcmp(path, (*paths)[i]) == 0) 177 break; 178 } 179 if (i != *n) { 180 log_debug("%s: duplicate path: %s", __func__, path); 181 free(path); 182 continue; 183 } 184 *paths = xreallocarray(*paths, (*n) + 1, sizeof *paths); 185 (*paths)[(*n)++] = path; 186 } 187 free(copy); 188} 189 190static char * 191make_label(const char *label, char **cause) 192{ 193 char **paths, *path, *base; 194 u_int i, n; 195 struct stat sb; 196 uid_t uid; 197 198 *cause = NULL; 199 if (label == NULL) 200 label = "default"; 201 uid = getuid(); 202 203 expand_paths(TMUX_SOCK, &paths, &n, 1); 204 if (n == 0) { 205 xasprintf(cause, "no suitable socket path"); 206 return (NULL); 207 } 208 path = paths[0]; /* can only have one socket! */ 209 for (i = 1; i < n; i++) 210 free(paths[i]); 211 free(paths); 212 213 xasprintf(&base, "%s/tmux-%ld", path, (long)uid); 214 if (mkdir(base, S_IRWXU) != 0 && errno != EEXIST) 215 goto fail; 216 if (lstat(base, &sb) != 0) 217 goto fail; 218 if (!S_ISDIR(sb.st_mode)) { 219 errno = ENOTDIR; 220 goto fail; 221 } 222 if (sb.st_uid != uid || (sb.st_mode & S_IRWXO) != 0) { 223 errno = EACCES; 224 goto fail; 225 } 226 xasprintf(&path, "%s/%s", base, label); 227 free(base); 228 return (path); 229 230fail: 231 xasprintf(cause, "error creating %s (%s)", base, strerror(errno)); 232 free(base); 233 return (NULL); 234} 235 236void 237setblocking(int fd, int state) 238{ 239 int mode; 240 241 if ((mode = fcntl(fd, F_GETFL)) != -1) { 242 if (!state) 243 mode |= O_NONBLOCK; 244 else 245 mode &= ~O_NONBLOCK; 246 fcntl(fd, F_SETFL, mode); 247 } 248} 249 250uint64_t 251get_timer(void) 252{ 253 struct timespec ts; 254 255 /* 256 * We want a timestamp in milliseconds suitable for time measurement, 257 * so prefer the monotonic clock. 258 */ 259 if (clock_gettime(CLOCK_MONOTONIC, &ts) != 0) 260 clock_gettime(CLOCK_REALTIME, &ts); 261 return ((ts.tv_sec * 1000ULL) + (ts.tv_nsec / 1000000ULL)); 262} 263 264const char * 265sig2name(int signo) 266{ 267 static char s[11]; 268 269 if (signo > 0 && signo < NSIG) 270 return (sys_signame[signo]); 271 xsnprintf(s, sizeof s, "%d", signo); 272 return (s); 273} 274 275const char * 276find_cwd(void) 277{ 278 char resolved1[PATH_MAX], resolved2[PATH_MAX]; 279 static char cwd[PATH_MAX]; 280 const char *pwd; 281 282 if (getcwd(cwd, sizeof cwd) == NULL) 283 return (NULL); 284 if ((pwd = getenv("PWD")) == NULL || *pwd == '\0') 285 return (cwd); 286 287 /* 288 * We want to use PWD so that symbolic links are maintained, 289 * but only if it matches the actual working directory. 290 */ 291 if (realpath(pwd, resolved1) == NULL) 292 return (cwd); 293 if (realpath(cwd, resolved2) == NULL) 294 return (cwd); 295 if (strcmp(resolved1, resolved2) != 0) 296 return (cwd); 297 return (pwd); 298} 299 300const char * 301find_home(void) 302{ 303 struct passwd *pw; 304 static const char *home; 305 306 if (home != NULL) 307 return (home); 308 309 home = getenv("HOME"); 310 if (home == NULL || *home == '\0') { 311 pw = getpwuid(getuid()); 312 if (pw != NULL) 313 home = pw->pw_dir; 314 else 315 home = NULL; 316 } 317 318 return (home); 319} 320 321const char * 322getversion(void) 323{ 324 static char *version; 325 struct utsname u; 326 327 if (version == NULL) { 328 if (uname(&u) < 0) 329 fatalx("uname failed"); 330 xasprintf(&version, "openbsd-%s", u.release); 331 } 332 return (version); 333} 334 335int 336main(int argc, char **argv) 337{ 338 char *path = NULL, *label = NULL; 339 char *cause, **var; 340 const char *s, *cwd; 341 int opt, keys, feat = 0, fflag = 0; 342 uint64_t flags = 0; 343 const struct options_table_entry *oe; 344 u_int i; 345 346 if (setlocale(LC_CTYPE, "en_US.UTF-8") == NULL && 347 setlocale(LC_CTYPE, "C.UTF-8") == NULL) { 348 if (setlocale(LC_CTYPE, "") == NULL) 349 errx(1, "invalid LC_ALL, LC_CTYPE or LANG"); 350 s = nl_langinfo(CODESET); 351 if (strcasecmp(s, "UTF-8") != 0 && strcasecmp(s, "UTF8") != 0) 352 errx(1, "need UTF-8 locale (LC_CTYPE) but have %s", s); 353 } 354 355 setlocale(LC_TIME, ""); 356 tzset(); 357 358 if (**argv == '-') 359 flags = CLIENT_LOGIN; 360 361 global_environ = environ_create(); 362 for (var = environ; *var != NULL; var++) 363 environ_put(global_environ, *var, 0); 364 if ((cwd = find_cwd()) != NULL) 365 environ_set(global_environ, "PWD", 0, "%s", cwd); 366 expand_paths(TMUX_CONF, &cfg_files, &cfg_nfiles, 1); 367 368 while ((opt = getopt(argc, argv, "2c:CDdf:lL:NqS:T:uUvV")) != -1) { 369 switch (opt) { 370 case '2': 371 tty_add_features(&feat, "256", ":,"); 372 break; 373 case 'c': 374 shell_command = optarg; 375 break; 376 case 'D': 377 flags |= CLIENT_NOFORK; 378 break; 379 case 'C': 380 if (flags & CLIENT_CONTROL) 381 flags |= CLIENT_CONTROLCONTROL; 382 else 383 flags |= CLIENT_CONTROL; 384 break; 385 case 'f': 386 if (!fflag) { 387 fflag = 1; 388 for (i = 0; i < cfg_nfiles; i++) 389 free(cfg_files[i]); 390 cfg_nfiles = 0; 391 } 392 cfg_files = xreallocarray(cfg_files, cfg_nfiles + 1, 393 sizeof *cfg_files); 394 cfg_files[cfg_nfiles++] = xstrdup(optarg); 395 cfg_quiet = 0; 396 break; 397 case 'V': 398 printf("%s %s\n", getprogname(), getversion()); 399 exit(0); 400 case 'l': 401 flags |= CLIENT_LOGIN; 402 break; 403 case 'L': 404 free(label); 405 label = xstrdup(optarg); 406 break; 407 case 'N': 408 flags |= CLIENT_NOSTARTSERVER; 409 break; 410 case 'q': 411 break; 412 case 'S': 413 free(path); 414 path = xstrdup(optarg); 415 break; 416 case 'T': 417 tty_add_features(&feat, optarg, ":,"); 418 break; 419 case 'u': 420 flags |= CLIENT_UTF8; 421 break; 422 case 'v': 423 log_add_level(); 424 break; 425 default: 426 usage(); 427 } 428 } 429 argc -= optind; 430 argv += optind; 431 432 if (shell_command != NULL && argc != 0) 433 usage(); 434 if ((flags & CLIENT_NOFORK) && argc != 0) 435 usage(); 436 437 if ((ptm_fd = getptmfd()) == -1) 438 err(1, "getptmfd"); 439 if (pledge("stdio rpath wpath cpath flock fattr unix getpw sendfd " 440 "recvfd proc exec tty ps", NULL) != 0) 441 err(1, "pledge"); 442 443 /* 444 * tmux is a UTF-8 terminal, so if TMUX is set, assume UTF-8. 445 * Otherwise, if the user has set LC_ALL, LC_CTYPE or LANG to contain 446 * UTF-8, it is a safe assumption that either they are using a UTF-8 447 * terminal, or if not they know that output from UTF-8-capable 448 * programs may be wrong. 449 */ 450 if (getenv("TMUX") != NULL) 451 flags |= CLIENT_UTF8; 452 else { 453 s = getenv("LC_ALL"); 454 if (s == NULL || *s == '\0') 455 s = getenv("LC_CTYPE"); 456 if (s == NULL || *s == '\0') 457 s = getenv("LANG"); 458 if (s == NULL || *s == '\0') 459 s = ""; 460 if (strcasestr(s, "UTF-8") != NULL || 461 strcasestr(s, "UTF8") != NULL) 462 flags |= CLIENT_UTF8; 463 } 464 465 global_options = options_create(NULL); 466 global_s_options = options_create(NULL); 467 global_w_options = options_create(NULL); 468 for (oe = options_table; oe->name != NULL; oe++) { 469 if (oe->scope & OPTIONS_TABLE_SERVER) 470 options_default(global_options, oe); 471 if (oe->scope & OPTIONS_TABLE_SESSION) 472 options_default(global_s_options, oe); 473 if (oe->scope & OPTIONS_TABLE_WINDOW) 474 options_default(global_w_options, oe); 475 } 476 477 /* 478 * The default shell comes from SHELL or from the user's passwd entry 479 * if available. 480 */ 481 options_set_string(global_s_options, "default-shell", 0, "%s", 482 getshell()); 483 484 /* Override keys to vi if VISUAL or EDITOR are set. */ 485 if ((s = getenv("VISUAL")) != NULL || (s = getenv("EDITOR")) != NULL) { 486 options_set_string(global_options, "editor", 0, "%s", s); 487 if (strrchr(s, '/') != NULL) 488 s = strrchr(s, '/') + 1; 489 if (strstr(s, "vi") != NULL) 490 keys = MODEKEY_VI; 491 else 492 keys = MODEKEY_EMACS; 493 options_set_number(global_s_options, "status-keys", keys); 494 options_set_number(global_w_options, "mode-keys", keys); 495 } 496 497 /* 498 * If socket is specified on the command-line with -S or -L, it is 499 * used. Otherwise, $TMUX is checked and if that fails "default" is 500 * used. 501 */ 502 if (path == NULL && label == NULL) { 503 s = getenv("TMUX"); 504 if (s != NULL && *s != '\0' && *s != ',') { 505 path = xstrdup(s); 506 path[strcspn(path, ",")] = '\0'; 507 } 508 } 509 if (path == NULL) { 510 if ((path = make_label(label, &cause)) == NULL) { 511 if (cause != NULL) { 512 fprintf(stderr, "%s\n", cause); 513 free(cause); 514 } 515 exit(1); 516 } 517 flags |= CLIENT_DEFAULTSOCKET; 518 } 519 socket_path = path; 520 free(label); 521 522 /* Pass control to the client. */ 523 exit(client_main(event_init(), argc, argv, flags, feat)); 524} 525