code.delx.au - gnu-emacs/blob - lib-src/emacsclient.c

   1 /* Client process that communicates with GNU Emacs acting as server.
   2    Copyright (C) 1986, 1987, 1994, 1999 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21
  22 #define NO_SHORTNAMES
  23 #include <../src/config.h>
  24 #undef signal
  25
  26 #include <stdio.h>
  27 #include <getopt.h>
  28 #ifdef HAVE_UNISTD_H
  29 #include <unistd.h>
  30 #endif
  31
  32 char *getenv (), *getwd ();
  33 char *getcwd ();
  34
  35 /* This is defined with -D from the compilation command,
  36    which extracts it from ../lisp/version.el.  */
  37
  38 #ifndef VERSION
  39 #define VERSION "unspecified"
  40 #endif
  41 \f
  42 /* Name used to invoke this program.  */
  43 char *progname;
  44
  45 /* Nonzero means don't wait for a response from Emacs.  --no-wait.  */
  46 int nowait = 0;
  47
  48 void print_help_and_exit ();
  49
  50 struct option longopts[] =
  51 {
  52   { "no-wait",  no_argument,       NULL, 'n' },
  53   { "help",     no_argument,       NULL, 'H' },
  54   { "version",  no_argument,       NULL, 'V' },
  55   { "alternate-editor",required_argument, NULL, 'a' },
  56   { 0 }
  57 };
  58
  59
  60 const char * alternate_editor = NULL;
  61
  62 /* Decode the options from argv and argc.
  63    The global variable `optind' will say how many arguments we used up.  */
  64
  65 void
  66 decode_options (argc, argv)
  67      int argc;
  68      char **argv;
  69 {
  70   while (1)
  71     {
  72       int opt = getopt_long (argc, argv,
  73                              "VHna:", longopts, 0);
  74
  75       if (opt == EOF)
  76         break;
  77
  78       alternate_editor = getenv ("ALTERNATE_EDITOR");
  79
  80       switch (opt)
  81         {
  82         case 0:
  83           /* If getopt returns 0, then it has already processed a
  84              long-named option.  We should do nothing.  */
  85           break;
  86
  87         case 'a':
  88           alternate_editor = optarg;
  89           break;
  90
  91         case 'n':
  92           nowait = 1;
  93           break;
  94
  95         case 'V':
  96           fprintf (stderr, "emacsclient %s\n", VERSION);
  97           exit (1);
  98           break;
  99
 100         case 'H':
 101         default:
 102           print_help_and_exit ();
 103         }
 104     }
 105 }
 106
 107 void
 108 print_help_and_exit ()
 109 {
 110   fprintf (stderr,
 111            "Usage: %s [-a ALTERNATE-EDITOR] [-n] [--no-wait] [+LINENUMBER] FILENAME\n",
 112            progname);
 113   fprintf (stderr,
 114            "Or %s --version\n",
 115            progname);
 116   fprintf (stderr,
 117            "Report bugs to bug-gnu-emacs@gnu.org.\n");
 118   exit (1);
 119 }
 120
 121 /* Return a copy of NAME, inserting a &
 122    before each &, each space, and any initial -.
 123    Change spaces to underscores, too, so that the
 124    return value never contains a space.  */
 125
 126 char *
 127 quote_file_name (name)
 128      char *name;
 129 {
 130   char *copy = (char *) malloc (strlen (name) * 2 + 1);
 131   char *p, *q;
 132
 133   p = name;
 134   q = copy;
 135   while (*p)
 136     {
 137       if (*p == ' ')
 138         {
 139           *q++ = '&';
 140           *q++ = '_';
 141           p++;
 142         }
 143       else
 144         {
 145           if (*p == '&' || (*p == '-' && p == name))
 146             *q++ = '&';
 147           *q++ = *p++;
 148         }
 149     }
 150   *q++ = 0;
 151
 152
 153   return copy;
 154 }
 155
 156 /* Like malloc but get fatal error if memory is exhausted.  */
 157
 158 long *
 159 xmalloc (size)
 160      unsigned int size;
 161 {
 162   long *result = (long *) malloc (size);
 163   if (result == NULL)
 164   {
 165     perror ("malloc");
 166     exit (1);
 167   }
 168   return result;
 169 }
 170 \f
 171 /*
 172   Try to run a different command, or --if no alternate editor is
 173   defined-- exit with an errorcode.
 174 */
 175 fail (argc, argv)
 176      int argc;
 177      char **argv;
 178 {
 179   if (alternate_editor)
 180     {
 181       int i = optind -1 ;
 182       execvp (alternate_editor, argv + i);
 183     }
 184   else
 185     {
 186       exit (1);
 187     }
 188 }
 189
 190
 191
 192 \f
 193 #if !defined (HAVE_SOCKETS) && !defined (HAVE_SYSVIPC)
 194
 195 main (argc, argv)
 196      int argc;
 197      char **argv;
 198 {
 199   fprintf (stderr, "%s: Sorry, the Emacs server is supported only\n",
 200            argv[0]);
 201   fprintf (stderr, "on systems with Berkeley sockets or System V IPC.\n");
 202
 203   fail (argc, argv);
 204 }
 205
 206 #else /* HAVE_SOCKETS or HAVE_SYSVIPC */
 207
 208 #if defined (HAVE_SOCKETS) && ! defined (NO_SOCKETS_IN_FILE_SYSTEM)
 209 /* BSD code is very different from SYSV IPC code */
 210
 211 #include <sys/types.h>
 212 #include <sys/socket.h>
 213 #include <sys/un.h>
 214 #include <sys/stat.h>
 215 #include <errno.h>
 216
 217 extern char *strerror ();
 218 extern int errno;
 219
 220 int
 221 main (argc, argv)
 222      int argc;
 223      char **argv;
 224 {
 225   char *system_name;
 226   int system_name_length;
 227   int s, i;
 228   FILE *out, *in;
 229   struct sockaddr_un server;
 230   char *homedir, *cwd, *str;
 231   char string[BUFSIZ];
 232
 233   progname = argv[0];
 234
 235   /* Process options.  */
 236   decode_options (argc, argv);
 237
 238   if (argc - optind < 1)
 239     print_help_and_exit ();
 240
 241   /*
 242    * Open up an AF_UNIX socket in this person's home directory
 243    */
 244
 245   if ((s = socket (AF_UNIX, SOCK_STREAM, 0)) < 0)
 246     {
 247       fprintf (stderr, "%s: ", argv[0]);
 248       perror ("socket");
 249       fail (argc, argv);
 250     }
 251
 252   server.sun_family = AF_UNIX;
 253
 254   {
 255     system_name_length = 32;
 256
 257     while (1)
 258       {
 259         system_name = (char *) xmalloc (system_name_length + 1);
 260
 261         /* system_name must be null-terminated string.  */
 262         system_name[system_name_length] = '\0';
 263
 264         if (gethostname (system_name, system_name_length) == 0)
 265           break;
 266
 267         free (system_name);
 268         system_name_length *= 2;
 269       }
 270   }
 271
 272 #ifndef SERVER_HOME_DIR
 273   {
 274     struct stat statbfr;
 275
 276     sprintf (server.sun_path, "/tmp/esrv%d-%s", geteuid (), system_name);
 277
 278     if (stat (server.sun_path, &statbfr) == -1)
 279       {
 280         if (errno == ENOENT)
 281           fprintf (stderr,
 282                    "%s: can't find socket; have you started the server?\n",
 283                    argv[0]);
 284         else
 285           fprintf (stderr, "%s: can't stat %s: %s\n",
 286                    argv[0], server.sun_path, strerror (errno));
 287         fail (argc, argv);
 288       }
 289     if (statbfr.st_uid != geteuid ())
 290       {
 291         fprintf (stderr, "%s: Invalid socket owner\n", argv[0]);
 292         fail (argc, argv);
 293       }
 294   }
 295 #else
 296   if ((homedir = getenv ("HOME")) == NULL)
 297     {
 298       fprintf (stderr, "%s: No home directory\n", argv[0]);
 299       fail (argc, argv);
 300     }
 301   strcpy (server.sun_path, homedir);
 302   strcat (server.sun_path, "/.emacs-server-");
 303   strcat (server.sun_path, system_name);
 304 #endif
 305
 306   if (connect (s, (struct sockaddr *) &server, strlen (server.sun_path) + 2)
 307       < 0)
 308     {
 309       fprintf (stderr, "%s: ", argv[0]);
 310       perror ("connect");
 311       fail (argc, argv);
 312     }
 313
 314   /* We use the stream OUT to send our command to the server.  */
 315   if ((out = fdopen (s, "r+")) == NULL)
 316     {
 317       fprintf (stderr, "%s: ", argv[0]);
 318       perror ("fdopen");
 319       fail (argc, argv);
 320     }
 321
 322   /* We use the stream IN to read the response.
 323      We used to use just one stream for both output and input
 324      on the socket, but reversing direction works nonportably:
 325      on some systems, the output appears as the first input;
 326      on other systems it does not.  */
 327   if ((in = fdopen (s, "r+")) == NULL)
 328     {
 329       fprintf (stderr, "%s: ", argv[0]);
 330       perror ("fdopen");
 331       fail (argc, argv);
 332     }
 333
 334 #ifdef BSD_SYSTEM
 335   cwd = getwd (string);
 336 #else
 337   cwd = getcwd (string, sizeof string);
 338 #endif
 339   if (cwd == 0)
 340     {
 341       /* getwd puts message in STRING if it fails.  */
 342       fprintf (stderr, "%s: %s (%s)\n", argv[0],
 343 #ifdef BSD_SYSTEM
 344                string,
 345 #else
 346                "Cannot get current working directory",
 347 #endif
 348                strerror (errno));
 349       fail (argc, argv);
 350     }
 351
 352   if (nowait)
 353     fprintf (out, "-nowait ");
 354
 355   for (i = optind; i < argc; i++)
 356     {
 357       if (*argv[i] == '+')
 358         {
 359           char *p = argv[i] + 1;
 360           while (*p >= '0' && *p <= '9') p++;
 361           if (*p != 0)
 362             fprintf (out, "%s/", quote_file_name (cwd));
 363         }
 364       else if (*argv[i] != '/')
 365         fprintf (out, "%s/", quote_file_name (cwd));
 366
 367       fprintf (out, "%s ", quote_file_name (argv[i]));
 368     }
 369   fprintf (out, "\n");
 370   fflush (out);
 371
 372   /* Maybe wait for an answer.   */
 373   if (nowait)
 374     return 0;
 375
 376   printf ("Waiting for Emacs...");
 377   fflush (stdout);
 378
 379   /* Now, wait for an answer and print any messages.  On some systems,
 380      the first line we read will actually be the output we just sent.
 381      We can't predict whether that will happen, so if it does, we
 382      detect it by recognizing `Client: ' at the beginning.  */
 383
 384   while (str = fgets (string, BUFSIZ, in))
 385     printf ("%s", str);
 386
 387   return 0;
 388 }
 389
 390 #else /* This is the SYSV IPC section */
 391
 392 #include <sys/types.h>
 393 #include <sys/ipc.h>
 394 #include <sys/msg.h>
 395 #include <sys/utsname.h>
 396 #include <stdio.h>
 397 #include <errno.h>
 398 extern int errno;
 399
 400 char *getwd (), *getcwd (), *getenv ();
 401 struct utsname system_name;
 402
 403 main (argc, argv)
 404      int argc;
 405      char **argv;
 406 {
 407   int s;
 408   key_t key;
 409   /* Size of text allocated in MSGP.  */
 410   int size_allocated = BUFSIZ;
 411   /* Amount of text used in MSGP.  */
 412   int used;
 413   struct msgbuf *msgp
 414     = (struct msgbuf *) malloc (sizeof (struct msgbuf) + size_allocated);
 415   struct msqid_ds * msg_st;
 416   char *homedir, buf[BUFSIZ];
 417   char gwdirb[BUFSIZ];
 418   char *cwd;
 419   char *temp;
 420
 421   progname = argv[0];
 422
 423   /* Process options.  */
 424   decode_options (argc, argv);
 425
 426   if (argc - optind < 1)
 427     print_help_and_exit ();
 428
 429   /*
 430    * Create a message queue using ~/.emacs-server as the path for ftok
 431    */
 432   if ((homedir = getenv ("HOME")) == NULL)
 433     {
 434       fprintf (stderr, "%s: No home directory\n", argv[0]);
 435       exit (1);
 436     }
 437   strcpy (buf, homedir);
 438 #ifndef HAVE_LONG_FILE_NAMES
 439   /* If file names are short, we can't fit the host name.  */
 440   strcat (buf, "/.emacs-server");
 441 #else
 442   strcat (buf, "/.emacs-server-");
 443   uname (&system_name);
 444   strcat (buf, system_name.nodename);
 445 #endif
 446   creat (buf, 0600);
 447   key = ftok (buf, 1);  /* unlikely to be anyone else using it */
 448   s = msgget (key, 0600 | IPC_CREAT);
 449   if (s == -1)
 450     {
 451       fprintf (stderr, "%s: ", argv[0]);
 452       perror ("msgget");
 453       exit (1);
 454     }
 455
 456   /* Determine working dir, so we can prefix it to all the arguments.  */
 457 #ifdef BSD_SYSTEM
 458   temp = getwd (gwdirb);
 459 #else
 460   temp = getcwd (gwdirb, sizeof gwdirb);
 461 #endif
 462
 463   cwd = gwdirb;
 464   if (temp != 0)
 465     {
 466       /* On some systems, cwd can look like `@machine/...';
 467          ignore everything before the first slash in such a case.  */
 468       while (*cwd && *cwd != '/')
 469         cwd++;
 470       strcat (cwd, "/");
 471     }
 472   else
 473     {
 474 #ifdef BSD_SYSTEM
 475       fprintf (stderr, "%s: %s\n", argv[0], cwd);
 476 #else
 477       fprintf (stderr, "%s: Cannot get current working directory: %s\n",
 478                argv[0], strerror (errno));
 479 #endif
 480       fail (argc, argv);
 481     }
 482
 483   msgp->mtext[0] = 0;
 484   used = 0;
 485
 486   if (nowait)
 487     {
 488       strcat (msgp->mtext, "-nowait ");
 489       used += 8;
 490     }
 491
 492   argc -= optind;
 493   argv += optind;
 494
 495   while (argc)
 496     {
 497       int need_cwd = 0;
 498       char *modified_arg = argv[0];
 499
 500       if (*modified_arg == '+')
 501         {
 502           char *p = modified_arg + 1;
 503           while (*p >= '0' && *p <= '9') p++;
 504           if (*p != 0)
 505             need_cwd = 1;
 506         }
 507       else if (*modified_arg != '/')
 508         need_cwd = 1;
 509
 510       modified_arg = quote_file_name (modified_arg);
 511
 512       if (need_cwd)
 513         /* Overestimate in case we have to quote something in CWD.  */
 514         used += 2 * strlen (cwd);
 515       used += strlen (modified_arg) + 1;
 516       while (used + 2 > size_allocated)
 517         {
 518           size_allocated *= 2;
 519           msgp = (struct msgbuf *) realloc (msgp,
 520                                             (sizeof (struct msgbuf)
 521                                              + size_allocated));
 522         }
 523
 524       if (need_cwd)
 525         strcat (msgp->mtext, quote_file_name (cwd));
 526
 527       strcat (msgp->mtext, modified_arg);
 528       strcat (msgp->mtext, " ");
 529       argv++; argc--;
 530     }
 531   strcat (msgp->mtext, "\n");
 532 #ifdef HPUX /* HPUX has a bug.  */
 533   if (strlen (msgp->mtext) >= 512)
 534     {
 535       fprintf (stderr, "%s: args too long for msgsnd\n", progname);
 536       fail (argc, argv);
 537     }
 538 #endif
 539   msgp->mtype = 1;
 540   if (msgsnd (s, msgp, strlen (msgp->mtext)+1, 0) < 0)
 541     {
 542       fprintf (stderr, "%s: ", progname);
 543       perror ("msgsnd");
 544       fail (argc, argv);
 545     }
 546
 547   /* Maybe wait for an answer.   */
 548   if (nowait)
 549     return 0;
 550
 551   printf ("Waiting for Emacs...");
 552   fflush (stdout);
 553
 554   msgrcv (s, msgp, BUFSIZ, getpid (), 0);       /* wait for anything back */
 555   strcpy (buf, msgp->mtext);
 556
 557   printf ("\n");
 558   if (*buf)
 559     printf ("%s\n", buf);
 560   exit (0);
 561 }
 562
 563 #endif /* HAVE_SYSVIPC */
 564
 565 #endif /* HAVE_SOCKETS or HAVE_SYSVIPC */
 566 \f
 567 #ifndef HAVE_STRERROR
 568 char *
 569 strerror (errnum)
 570      int errnum;
 571 {
 572   extern char *sys_errlist[];
 573   extern int sys_nerr;
 574
 575   if (errnum >= 0 && errnum < sys_nerr)
 576     return sys_errlist[errnum];
 577   return (char *) "Unknown error";
 578 }
 579
 580 #endif /* ! HAVE_STRERROR */