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 <paths.h>
  26 #include <pwd.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <unistd.h>
  30
  31 #include "tmux.h"
  32
  33 #ifdef DEBUG
  34 extern char     *malloc_options;
  35 #endif
  36
  37 struct options   global_options;        /* server options */
  38 struct options   global_s_options;      /* session options */
  39 struct options   global_w_options;      /* window options */
  40 struct environ   global_environ;
  41
  42 struct event_base *ev_base;
  43
  44 char            *cfg_file;
  45 char            *shell_cmd;
  46 int              debug_level;
  47 time_t           start_time;
  48 char             socket_path[MAXPATHLEN];
  49 int              login_shell;
  50 char            *environ_path;
  51 pid_t            environ_pid;
  52 u_int            environ_idx;
  53
  54 __dead void      usage(void);
  55 void             parseenvironment(void);
  56 char            *makesocketpath(const char *);
  57
  58 __dead void
  59 usage(void)
  60 {
  61         fprintf(stderr,
  62             "usage: %s [-28lquv] [-c shell-command] [-f file] [-L socket-name]\n"
  63             "            [-S socket-path] [command [flags]]\n",
  64             __progname);
  65         exit(1);
  66 }
  67
  68 void
  69 logfile(const char *name)
  70 {
  71         char    *path;
  72
  73         log_close();
  74         if (debug_level > 0) {
  75                 xasprintf(&path, "tmux-%s-%ld.log", name, (long) getpid());
  76                 log_open_file(debug_level, path);
  77                 xfree(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' || areshell(shell))
 102                 return (0);
 103         if (access(shell, X_OK) != 0)
 104                 return (0);
 105         return (1);
 106 }
 107
 108 int
 109 areshell(const char *shell)
 110 {
 111         const char      *progname, *ptr;
 112
 113         if ((ptr = strrchr(shell, '/')) != NULL)
 114                 ptr++;
 115         else
 116                 ptr = shell;
 117         progname = __progname;
 118         if (*progname == '-')
 119                 progname++;
 120         if (strcmp(ptr, progname) == 0)
 121                 return (1);
 122         return (0);
 123 }
 124
 125 void
 126 parseenvironment(void)
 127 {
 128         char            *env, *path_pid, *pid_idx, buf[256];
 129         size_t           len;
 130         const char      *errstr;
 131         long long        ll;
 132
 133         environ_pid = -1;
 134         if ((env = getenv("TMUX")) == NULL)
 135                 return;
 136
 137         if ((path_pid = strchr(env, ',')) == NULL || path_pid == env)
 138                 return;
 139         if ((pid_idx = strchr(path_pid + 1, ',')) == NULL)
 140                 return;
 141         if ((pid_idx == path_pid + 1 || pid_idx[1] == '\0'))
 142                 return;
 143
 144         /* path */
 145         len = path_pid - env;
 146         environ_path = xmalloc(len + 1);
 147         memcpy(environ_path, env, len);
 148         environ_path[len] = '\0';
 149
 150         /* pid */
 151         len = pid_idx - path_pid - 1;
 152         if (len > (sizeof buf) - 1)
 153                 return;
 154         memcpy(buf, path_pid + 1, len);
 155         buf[len] = '\0';
 156
 157         ll = strtonum(buf, 0, LONG_MAX, &errstr);
 158         if (errstr != NULL)
 159                 return;
 160         environ_pid = ll;
 161
 162         /* idx */
 163         ll = strtonum(pid_idx + 1, 0, UINT_MAX, &errstr);
 164         if (errstr != NULL)
 165                 return;
 166         environ_idx = ll;
 167 }
 168
 169 char *
 170 makesocketpath(const char *label)
 171 {
 172         char            base[MAXPATHLEN], *path, *s;
 173         struct stat     sb;
 174         u_int           uid;
 175
 176         uid = getuid();
 177         if ((s = getenv("TMPDIR")) == NULL || *s == '\0')
 178                 xsnprintf(base, sizeof base, "%s/tmux-%u", _PATH_TMP, uid);
 179         else
 180                 xsnprintf(base, sizeof base, "%s/tmux-%u", s, uid);
 181
 182         if (mkdir(base, S_IRWXU) != 0 && errno != EEXIST)
 183                 return (NULL);
 184
 185         if (lstat(base, &sb) != 0)
 186                 return (NULL);
 187         if (!S_ISDIR(sb.st_mode)) {
 188                 errno = ENOTDIR;
 189                 return (NULL);
 190         }
 191         if (sb.st_uid != uid || (sb.st_mode & (S_IRWXG|S_IRWXO)) != 0) {
 192                 errno = EACCES;
 193                 return (NULL);
 194         }
 195
 196         xasprintf(&path, "%s/%s", base, label);
 197         return (path);
 198 }
 199
 200 void
 201 setblocking(int fd, int state)
 202 {
 203         int mode;
 204
 205         if ((mode = fcntl(fd, F_GETFL)) != -1) {
 206                 if (!state)
 207                         mode |= O_NONBLOCK;
 208                 else
 209                         mode &= ~O_NONBLOCK;
 210                 fcntl(fd, F_SETFL, mode);
 211         }
 212 }
 213
 214 __dead void
 215 shell_exec(const char *shell, const char *shellcmd)
 216 {
 217         const char      *shellname, *ptr;
 218         char            *argv0;
 219
 220         ptr = strrchr(shell, '/');
 221         if (ptr != NULL && *(ptr + 1) != '\0')
 222                 shellname = ptr + 1;
 223         else
 224                 shellname = shell;
 225         if (login_shell)
 226                 xasprintf(&argv0, "-%s", shellname);
 227         else
 228                 xasprintf(&argv0, "%s", shellname);
 229         setenv("SHELL", shell, 1);
 230
 231         setblocking(STDIN_FILENO, 1);
 232         setblocking(STDOUT_FILENO, 1);
 233         setblocking(STDERR_FILENO, 1);
 234         closefrom(STDERR_FILENO + 1);
 235
 236         execl(shell, argv0, "-c", shellcmd, (char *) NULL);
 237         fatal("execl failed");
 238 }
 239
 240 int
 241 main(int argc, char **argv)
 242 {
 243         struct passwd   *pw;
 244         struct keylist  *keylist;
 245         char            *s, *path, *label, *home, **var;
 246         int              opt, flags, quiet, keys;
 247
 248 #ifdef DEBUG
 249         malloc_options = (char *) "AFGJPX";
 250 #endif
 251
 252         quiet = flags = 0;
 253         label = 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 (shell_cmd != NULL)
 267                                 xfree(shell_cmd);
 268                         shell_cmd = 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 (shell_cmd != 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         options_table_populate_tree(server_options_table, &global_options);
 332         options_set_number(&global_options, "quiet", quiet);
 333
 334         options_init(&global_s_options, NULL);
 335         options_table_populate_tree(session_options_table, &global_s_options);
 336         options_set_string(&global_s_options, "default-shell", "%s", getshell());
 337
 338         options_init(&global_w_options, NULL);
 339         options_table_populate_tree(window_options_table, &global_w_options);
 340
 341         /* Set the prefix option (its a list, so not in the table). */
 342         keylist = xmalloc(sizeof *keylist);
 343         ARRAY_INIT(keylist);
 344         ARRAY_ADD(keylist, '\002');
 345         options_set_data(&global_s_options, "prefix", keylist, xfree);
 346
 347         /* Enable UTF-8 if the first client is on UTF-8 terminal. */
 348         if (flags & IDENTIFY_UTF8) {
 349                 options_set_number(&global_s_options, "status-utf8", 1);
 350                 options_set_number(&global_s_options, "mouse-utf8", 1);
 351                 options_set_number(&global_w_options, "utf8", 1);
 352         }
 353
 354         /* Override keys to vi if VISUAL or EDITOR are set. */
 355         if ((s = getenv("VISUAL")) != NULL || (s = getenv("EDITOR")) != NULL) {
 356                 if (strrchr(s, '/') != NULL)
 357                         s = strrchr(s, '/') + 1;
 358                 if (strstr(s, "vi") != NULL)
 359                         keys = MODEKEY_VI;
 360                 else
 361                         keys = MODEKEY_EMACS;
 362                 options_set_number(&global_s_options, "status-keys", keys);
 363                 options_set_number(&global_w_options, "mode-keys", keys);
 364         }
 365
 366         /* Locate the configuration file. */
 367         if (cfg_file == NULL) {
 368                 home = getenv("HOME");
 369                 if (home == NULL || *home == '\0') {
 370                         pw = getpwuid(getuid());
 371                         if (pw != NULL)
 372                                 home = pw->pw_dir;
 373                 }
 374                 xasprintf(&cfg_file, "%s/%s", home, DEFAULT_CFG);
 375                 if (access(cfg_file, R_OK) != 0 && errno == ENOENT) {
 376                         xfree(cfg_file);
 377                         cfg_file = NULL;
 378                 }
 379         }
 380
 381         /*
 382          * Figure out the socket path. If specified on the command-line with -S
 383          * or -L, use it, otherwise try $TMUX or assume -L default.
 384          */
 385         parseenvironment();
 386         if (path == NULL) {
 387                 /* If no -L, use the environment. */
 388                 if (label == NULL) {
 389                         if (environ_path != NULL)
 390                                 path = xstrdup(environ_path);
 391                         else
 392                                 label = xstrdup("default");
 393                 }
 394
 395                 /* -L or default set. */
 396                 if (label != NULL) {
 397                         if ((path = makesocketpath(label)) == NULL) {
 398                                 log_warn("can't create socket");
 399                                 exit(1);
 400                         }
 401                 }
 402         }
 403         if (label != NULL)
 404                 xfree(label);
 405         if (realpath(path, socket_path) == NULL)
 406                 strlcpy(socket_path, path, sizeof socket_path);
 407         xfree(path);
 408
 409         /* Set process title. */
 410         setproctitle("%s (%s)", __progname, socket_path);
 411
 412         /* Pass control to the client. */
 413         ev_base = event_init();
 414         exit(client_main(argc, argv, flags));
 415 }