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 = -1;
  52 int              environ_idx = -1;
  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[256];
 129         long     pid;
 130         int      idx;
 131
 132         if ((env = getenv("TMUX")) == NULL)
 133                 return;
 134
 135         if (sscanf(env, "%255s,%ld,%d", path, &pid, &idx) != 3)
 136                 return;
 137         environ_path = xstrdup(path);
 138         environ_pid = pid;
 139         environ_idx = idx;
 140 }
 141
 142 char *
 143 makesocketpath(const char *label)
 144 {
 145         char            base[MAXPATHLEN], *path, *s;
 146         struct stat     sb;
 147         u_int           uid;
 148
 149         uid = getuid();
 150         if ((s = getenv("TMPDIR")) == NULL || *s == '\0')
 151                 xsnprintf(base, sizeof base, "%s/tmux-%u", _PATH_TMP, uid);
 152         else
 153                 xsnprintf(base, sizeof base, "%s/tmux-%u", s, uid);
 154
 155         if (mkdir(base, S_IRWXU) != 0 && errno != EEXIST)
 156                 return (NULL);
 157
 158         if (lstat(base, &sb) != 0)
 159                 return (NULL);
 160         if (!S_ISDIR(sb.st_mode)) {
 161                 errno = ENOTDIR;
 162                 return (NULL);
 163         }
 164         if (sb.st_uid != uid || (sb.st_mode & (S_IRWXG|S_IRWXO)) != 0) {
 165                 errno = EACCES;
 166                 return (NULL);
 167         }
 168
 169         xasprintf(&path, "%s/%s", base, label);
 170         return (path);
 171 }
 172
 173 void
 174 setblocking(int fd, int state)
 175 {
 176         int mode;
 177
 178         if ((mode = fcntl(fd, F_GETFL)) != -1) {
 179                 if (!state)
 180                         mode |= O_NONBLOCK;
 181                 else
 182                         mode &= ~O_NONBLOCK;
 183                 fcntl(fd, F_SETFL, mode);
 184         }
 185 }
 186
 187 __dead void
 188 shell_exec(const char *shell, const char *shellcmd)
 189 {
 190         const char      *shellname, *ptr;
 191         char            *argv0;
 192
 193         ptr = strrchr(shell, '/');
 194         if (ptr != NULL && *(ptr + 1) != '\0')
 195                 shellname = ptr + 1;
 196         else
 197                 shellname = shell;
 198         if (login_shell)
 199                 xasprintf(&argv0, "-%s", shellname);
 200         else
 201                 xasprintf(&argv0, "%s", shellname);
 202         setenv("SHELL", shell, 1);
 203
 204         setblocking(STDIN_FILENO, 1);
 205         setblocking(STDOUT_FILENO, 1);
 206         setblocking(STDERR_FILENO, 1);
 207         closefrom(STDERR_FILENO + 1);
 208
 209         execl(shell, argv0, "-c", shellcmd, (char *) NULL);
 210         fatal("execl failed");
 211 }
 212
 213 int
 214 main(int argc, char **argv)
 215 {
 216         struct passwd   *pw;
 217         struct keylist  *keylist;
 218         char            *s, *path, *label, *home, **var;
 219         int              opt, flags, quiet, keys;
 220
 221 #ifdef DEBUG
 222         malloc_options = (char *) "AFGJPX";
 223 #endif
 224
 225         quiet = flags = 0;
 226         label = path = NULL;
 227         login_shell = (**argv == '-');
 228         while ((opt = getopt(argc, argv, "28c:df:lL:qS:uUv")) != -1) {
 229                 switch (opt) {
 230                 case '2':
 231                         flags |= IDENTIFY_256COLOURS;
 232                         flags &= ~IDENTIFY_88COLOURS;
 233                         break;
 234                 case '8':
 235                         flags |= IDENTIFY_88COLOURS;
 236                         flags &= ~IDENTIFY_256COLOURS;
 237                         break;
 238                 case 'c':
 239                         if (shell_cmd != NULL)
 240                                 xfree(shell_cmd);
 241                         shell_cmd = xstrdup(optarg);
 242                         break;
 243                 case 'f':
 244                         if (cfg_file != NULL)
 245                                 xfree(cfg_file);
 246                         cfg_file = xstrdup(optarg);
 247                         break;
 248                 case 'l':
 249                         login_shell = 1;
 250                         break;
 251                 case 'L':
 252                         if (label != NULL)
 253                                 xfree(label);
 254                         label = xstrdup(optarg);
 255                         break;
 256                 case 'q':
 257                         quiet = 1;
 258                         break;
 259                 case 'S':
 260                         if (path != NULL)
 261                                 xfree(path);
 262                         path = xstrdup(optarg);
 263                         break;
 264                 case 'u':
 265                         flags |= IDENTIFY_UTF8;
 266                         break;
 267                 case 'v':
 268                         debug_level++;
 269                         break;
 270                 default:
 271                         usage();
 272                 }
 273         }
 274         argc -= optind;
 275         argv += optind;
 276
 277         if (shell_cmd != NULL && argc != 0)
 278                 usage();
 279
 280         log_open_tty(debug_level);
 281
 282         if (!(flags & IDENTIFY_UTF8)) {
 283                 /*
 284                  * If the user has set whichever of LC_ALL, LC_CTYPE or LANG
 285                  * exist (in that order) to contain UTF-8, it is a safe
 286                  * assumption that either they are using a UTF-8 terminal, or
 287                  * if not they know that output from UTF-8-capable programs may
 288                  * be wrong.
 289                  */
 290                 if ((s = getenv("LC_ALL")) == NULL) {
 291                         if ((s = getenv("LC_CTYPE")) == NULL)
 292                                 s = getenv("LANG");
 293                 }
 294                 if (s != NULL && (strcasestr(s, "UTF-8") != NULL ||
 295                     strcasestr(s, "UTF8") != NULL))
 296                         flags |= IDENTIFY_UTF8;
 297         }
 298
 299         environ_init(&global_environ);
 300         for (var = environ; *var != NULL; var++)
 301                 environ_put(&global_environ, *var);
 302
 303         options_init(&global_options, NULL);
 304         options_table_populate_tree(server_options_table, &global_options);
 305         options_set_number(&global_options, "quiet", quiet);
 306
 307         options_init(&global_s_options, NULL);
 308         options_table_populate_tree(session_options_table, &global_s_options);
 309         options_set_string(&global_s_options, "default-shell", "%s", getshell());
 310
 311         options_init(&global_w_options, NULL);
 312         options_table_populate_tree(window_options_table, &global_w_options);
 313
 314         /* Set the prefix option (its a list, so not in the table). */
 315         keylist = xmalloc(sizeof *keylist);
 316         ARRAY_INIT(keylist);
 317         ARRAY_ADD(keylist, '\002');
 318         options_set_data(&global_s_options, "prefix", keylist, xfree);
 319
 320         /* Enable UTF-8 if the first client is on UTF-8 terminal. */
 321         if (flags & IDENTIFY_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/%s", home, DEFAULT_CFG);
 348                 if (access(cfg_file, R_OK) != 0 && errno == ENOENT) {
 349                         xfree(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                                 log_warn("can't create socket");
 372                                 exit(1);
 373                         }
 374                 }
 375         }
 376         if (label != NULL)
 377                 xfree(label);
 378         if (realpath(path, socket_path) == NULL)
 379                 strlcpy(socket_path, path, sizeof socket_path);
 380         xfree(path);
 381
 382         /* Set process title. */
 383         setproctitle("%s (%s)", __progname, socket_path);
 384
 385         /* Pass control to the client. */
 386         ev_base = event_init();
 387         exit(client_main(argc, argv, flags));
 388 }