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
  22 #include <errno.h>
  23 #include <event.h>
  24 #include <fcntl.h>
  25 #include <locale.h>
  26 #include <paths.h>
  27 #include <pwd.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <unistd.h>
  31
  32 #include "tmux.h"
  33
  34 #ifdef DEBUG
  35 extern char     *malloc_options;
  36 #endif
  37
  38 struct options   global_options;        /* server options */
  39 struct options   global_s_options;      /* session options */
  40 struct options   global_w_options;      /* window options */
  41 struct environ   global_environ;
  42
  43 struct event_base *ev_base;
  44
  45 char            *cfg_file;
  46 char            *shell_cmd;
  47 int              debug_level;
  48 time_t           start_time;
  49 char             socket_path[MAXPATHLEN];
  50 int              login_shell;
  51 char            *environ_path;
  52 pid_t            environ_pid = -1;
  53 int              environ_session_id = -1;
  54
  55 __dead void      usage(void);
  56 void             parseenvironment(void);
  57 char            *makesocketpath(const char *);
  58
  59 __dead void
  60 usage(void)
  61 {
  62         fprintf(stderr,
  63             "usage: %s [-28lquv] [-c shell-command] [-f file] [-L socket-name]\n"
  64             "            [-S socket-path] [command [flags]]\n",
  65             __progname);
  66         exit(1);
  67 }
  68
  69 void
  70 logfile(const char *name)
  71 {
  72         char    *path;
  73
  74         if (debug_level > 0) {
  75                 xasprintf(&path, "tmux-%s-%ld.log", name, (long) getpid());
  76                 log_open(debug_level, path);
  77                 free(path);
  78         }
  79 }
  80
  81 const char *
  82 getshell(void)
  83 {
  84         struct passwd   *pw;
  85         const char      *shell;
  86
  87         shell = getenv("SHELL");
  88         if (checkshell(shell))
  89                 return (shell);
  90
  91         pw = getpwuid(getuid());
  92         if (pw != NULL && checkshell(pw->pw_shell))
  93                 return (pw->pw_shell);
  94
  95         return (_PATH_BSHELL);
  96 }
  97
  98 int
  99 checkshell(const char *shell)
 100 {
 101         if (shell == NULL || *shell == '\0' || *shell != '/')
 102                 return (0);
 103         if (areshell(shell))
 104                 return (0);
 105         if (access(shell, X_OK) != 0)
 106                 return (0);
 107         return (1);
 108 }
 109
 110 int
 111 areshell(const char *shell)
 112 {
 113         const char      *progname, *ptr;
 114
 115         if ((ptr = strrchr(shell, '/')) != NULL)
 116                 ptr++;
 117         else
 118                 ptr = shell;
 119         progname = __progname;
 120         if (*progname == '-')
 121                 progname++;
 122         if (strcmp(ptr, progname) == 0)
 123                 return (1);
 124         return (0);
 125 }
 126
 127 void
 128 parseenvironment(void)
 129 {
 130         char    *env, path[256];
 131         long     pid;
 132         int      id;
 133
 134         if ((env = getenv("TMUX")) == NULL)
 135                 return;
 136
 137         if (sscanf(env, "%255[^,],%ld,%d", path, &pid, &id) != 3)
 138                 return;
 139         environ_path = xstrdup(path);
 140         environ_pid = pid;
 141         environ_session_id = id;
 142 }
 143
 144 char *
 145 makesocketpath(const char *label)
 146 {
 147         char            base[MAXPATHLEN], realbase[MAXPATHLEN], *path, *s;
 148         struct stat     sb;
 149         u_int           uid;
 150
 151         uid = getuid();
 152         if ((s = getenv("TMUX_TMPDIR")) != NULL && *s != '\0')
 153                 xsnprintf(base, sizeof base, "%s/", s);
 154         else if ((s = getenv("TMPDIR")) != NULL && *s != '\0')
 155                 xsnprintf(base, sizeof base, "%s/tmux-%u", s, uid);
 156         else
 157                 xsnprintf(base, sizeof base, "%s/tmux-%u", _PATH_TMP, uid);
 158
 159         if (mkdir(base, S_IRWXU) != 0 && errno != EEXIST)
 160                 return (NULL);
 161
 162         if (lstat(base, &sb) != 0)
 163                 return (NULL);
 164         if (!S_ISDIR(sb.st_mode)) {
 165                 errno = ENOTDIR;
 166                 return (NULL);
 167         }
 168         if (sb.st_uid != uid || (!S_ISDIR(sb.st_mode) &&
 169                 sb.st_mode & (S_IRWXG|S_IRWXO)) != 0) {
 170                 errno = EACCES;
 171                 return (NULL);
 172         }
 173
 174         if (realpath(base, realbase) == NULL)
 175                 strlcpy(realbase, base, sizeof realbase);
 176
 177         xasprintf(&path, "%s/%s", realbase, label);
 178         return (path);
 179 }
 180
 181 void
 182 setblocking(int fd, int state)
 183 {
 184         int mode;
 185
 186         if ((mode = fcntl(fd, F_GETFL)) != -1) {
 187                 if (!state)
 188                         mode |= O_NONBLOCK;
 189                 else
 190                         mode &= ~O_NONBLOCK;
 191                 fcntl(fd, F_SETFL, mode);
 192         }
 193 }
 194
 195 __dead void
 196 shell_exec(const char *shell, const char *shellcmd)
 197 {
 198         const char      *shellname, *ptr;
 199         char            *argv0;
 200
 201         ptr = strrchr(shell, '/');
 202         if (ptr != NULL && *(ptr + 1) != '\0')
 203                 shellname = ptr + 1;
 204         else
 205                 shellname = shell;
 206         if (login_shell)
 207                 xasprintf(&argv0, "-%s", shellname);
 208         else
 209                 xasprintf(&argv0, "%s", shellname);
 210         setenv("SHELL", shell, 1);
 211
 212         setblocking(STDIN_FILENO, 1);
 213         setblocking(STDOUT_FILENO, 1);
 214         setblocking(STDERR_FILENO, 1);
 215         closefrom(STDERR_FILENO + 1);
 216
 217         execl(shell, argv0, "-c", shellcmd, (char *) NULL);
 218         fatal("execl failed");
 219 }
 220
 221 int
 222 main(int argc, char **argv)
 223 {
 224         struct passwd   *pw;
 225         char            *s, *path, *label, *home, **var, tmp[MAXPATHLEN];
 226         int              opt, flags, quiet, keys;
 227
 228 #ifdef DEBUG
 229         malloc_options = (char *) "AFGJPX";
 230 #endif
 231
 232         setlocale(LC_TIME, "");
 233
 234         quiet = flags = 0;
 235         label = path = NULL;
 236         login_shell = (**argv == '-');
 237         while ((opt = getopt(argc, argv, "2c:Cdf:lL:qS:uUv")) != -1) {
 238                 switch (opt) {
 239                 case '2':
 240                         flags |= CLIENT_256COLOURS;
 241                         break;
 242                 case 'c':
 243                         free(shell_cmd);
 244                         shell_cmd = xstrdup(optarg);
 245                         break;
 246                 case 'C':
 247                         if (flags & CLIENT_CONTROL)
 248                                 flags |= CLIENT_CONTROLCONTROL;
 249                         else
 250                                 flags |= CLIENT_CONTROL;
 251                         break;
 252                 case 'f':
 253                         free(cfg_file);
 254                         cfg_file = xstrdup(optarg);
 255                         break;
 256                 case 'l':
 257                         login_shell = 1;
 258                         break;
 259                 case 'L':
 260                         free(label);
 261                         label = xstrdup(optarg);
 262                         break;
 263                 case 'q':
 264                         quiet = 1;
 265                         break;
 266                 case 'S':
 267                         free(path);
 268                         path = xstrdup(optarg);
 269                         break;
 270                 case 'u':
 271                         flags |= CLIENT_UTF8;
 272                         break;
 273                 case 'v':
 274                         debug_level++;
 275                         break;
 276                 default:
 277                         usage();
 278                 }
 279         }
 280         argc -= optind;
 281         argv += optind;
 282
 283         if (shell_cmd != NULL && argc != 0)
 284                 usage();
 285
 286         if (!(flags & CLIENT_UTF8)) {
 287                 /*
 288                  * If the user has set whichever of LC_ALL, LC_CTYPE or LANG
 289                  * exist (in that order) to contain UTF-8, it is a safe
 290                  * assumption that either they are using a UTF-8 terminal, or
 291                  * if not they know that output from UTF-8-capable programs may
 292                  * be wrong.
 293                  */
 294                 if ((s = getenv("LC_ALL")) == NULL || *s == '\0') {
 295                         if ((s = getenv("LC_CTYPE")) == NULL || *s == '\0')
 296                                 s = getenv("LANG");
 297                 }
 298                 if (s != NULL && (strcasestr(s, "UTF-8") != NULL ||
 299                     strcasestr(s, "UTF8") != NULL))
 300                         flags |= CLIENT_UTF8;
 301         }
 302
 303         environ_init(&global_environ);
 304         for (var = environ; *var != NULL; var++)
 305                 environ_put(&global_environ, *var);
 306         if (getcwd(tmp, sizeof tmp) != NULL)
 307                 environ_set(&global_environ, "PWD", tmp);
 308
 309         options_init(&global_options, NULL);
 310         options_table_populate_tree(server_options_table, &global_options);
 311         options_set_number(&global_options, "quiet", quiet);
 312
 313         options_init(&global_s_options, NULL);
 314         options_table_populate_tree(session_options_table, &global_s_options);
 315         options_set_string(&global_s_options, "default-shell", "%s", getshell());
 316
 317         options_init(&global_w_options, NULL);
 318         options_table_populate_tree(window_options_table, &global_w_options);
 319
 320         /* Enable UTF-8 if the first client is on UTF-8 terminal. */
 321         if (flags & CLIENT_UTF8) {
 322                 options_set_number(&global_s_options, "status-utf8", 1);
 323                 options_set_number(&global_s_options, "mouse-utf8", 1);
 324                 options_set_number(&global_w_options, "utf8", 1);
 325         }
 326
 327         /* Override keys to vi if VISUAL or EDITOR are set. */
 328         if ((s = getenv("VISUAL")) != NULL || (s = getenv("EDITOR")) != NULL) {
 329                 if (strrchr(s, '/') != NULL)
 330                         s = strrchr(s, '/') + 1;
 331                 if (strstr(s, "vi") != NULL)
 332                         keys = MODEKEY_VI;
 333                 else
 334                         keys = MODEKEY_EMACS;
 335                 options_set_number(&global_s_options, "status-keys", keys);
 336                 options_set_number(&global_w_options, "mode-keys", keys);
 337         }
 338
 339         /* Locate the configuration file. */
 340         if (cfg_file == NULL) {
 341                 home = getenv("HOME");
 342                 if (home == NULL || *home == '\0') {
 343                         pw = getpwuid(getuid());
 344                         if (pw != NULL)
 345                                 home = pw->pw_dir;
 346                 }
 347                 xasprintf(&cfg_file, "%s/.tmux.conf", home);
 348                 if (access(cfg_file, R_OK) != 0 && errno == ENOENT) {
 349                         free(cfg_file);
 350                         cfg_file = NULL;
 351                 }
 352         }
 353
 354         /*
 355          * Figure out the socket path. If specified on the command-line with -S
 356          * or -L, use it, otherwise try $TMUX or assume -L default.
 357          */
 358         parseenvironment();
 359         if (path == NULL) {
 360                 /* If no -L, use the environment. */
 361                 if (label == NULL) {
 362                         if (environ_path != NULL)
 363                                 path = xstrdup(environ_path);
 364                         else
 365                                 label = xstrdup("default");
 366                 }
 367
 368                 /* -L or default set. */
 369                 if (label != NULL) {
 370                         if ((path = makesocketpath(label)) == NULL) {
 371                                 fprintf(stderr, "can't create socket: %s\n",
 372                                         strerror(errno));
 373                                 exit(1);
 374                         }
 375                 }
 376         }
 377         free(label);
 378         strlcpy(socket_path, path, sizeof socket_path);
 379         free(path);
 380
 381         /* Set process title. */
 382         setproctitle("%s (%s)", __progname, socket_path);
 383
 384         /* Pass control to the client. */
 385         ev_base = event_init();
 386         exit(client_main(argc, argv, flags));
 387 }