libguile/script.c

   1 /* Copyright (C) 1994, 1995, 1996, 1997, 1998, 2000, 2001 Free Software Foundation, Inc.
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License as published by
   4  * the Free Software Foundation; either version 2, or (at your option)
   5  * any later version.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  *
  12  * You should have received a copy of the GNU General Public License
  13  * along with this software; see the file COPYING.  If not, write to
  14  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  15  * Boston, MA 02111-1307 USA
  16  *
  17  * As a special exception, the Free Software Foundation gives permission
  18  * for additional uses of the text contained in its release of GUILE.
  19  *
  20  * The exception is that, if you link the GUILE library with other files
  21  * to produce an executable, this does not by itself cause the
  22  * resulting executable to be covered by the GNU General Public License.
  23  * Your use of that executable is in no way restricted on account of
  24  * linking the GUILE library code into it.
  25  *
  26  * This exception does not however invalidate any other reasons why
  27  * the executable file might be covered by the GNU General Public License.
  28  *
  29  * This exception applies only to the code released by the
  30  * Free Software Foundation under the name GUILE.  If you copy
  31  * code from other Free Software Foundation releases into a copy of
  32  * GUILE, as the General Public License permits, the exception does
  33  * not apply to the code that you add in this way.  To avoid misleading
  34  * anyone as to the status of such modified files, you must delete
  35  * this exception notice from them.
  36  *
  37  * If you write modifications of your own for GUILE, it is your choice
  38  * whether to permit this exception to apply to your modifications.
  39  * If you do not wish that, delete this exception notice.  */
  40
  41 /* "script.c" argv tricks for `#!' scripts.
  42    Authors: Aubrey Jaffer and Jim Blandy */
  43
  44 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
  45    gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
  46
  47 #include <stdio.h>
  48 #include <errno.h>
  49 #include <ctype.h>
  50
  51 #include "libguile/_scm.h"
  52 #include "libguile/gh.h"
  53 #include "libguile/load.h"
  54 #include "libguile/version.h"
  55
  56 #include "libguile/validate.h"
  57 #include "libguile/script.h"
  58
  59 #ifdef HAVE_STRING_H
  60 #include <string.h>
  61 #endif
  62
  63 #ifdef HAVE_UNISTD_H
  64 #include <unistd.h>             /* for X_OK define */
  65 #endif
  66
  67 /* Concatentate str2 onto str1 at position n and return concatenated
  68    string if file exists; 0 otherwise. */
  69
  70 static char *
  71 scm_cat_path (char *str1, const char *str2, long n)
  72 {
  73   if (!n)
  74     n = strlen (str2);
  75   if (str1)
  76     {
  77       long len = strlen (str1);
  78       str1 = (char *) realloc (str1, (scm_sizet) (len + n + 1));
  79       if (!str1)
  80         return 0L;
  81       strncat (str1 + len, str2, n);
  82       return str1;
  83     }
  84   str1 = (char *) malloc ((scm_sizet) (n + 1));
  85   if (!str1)
  86     return 0L;
  87   str1[0] = 0;
  88   strncat (str1, str2, n);
  89   return str1;
  90 }
  91
  92 #if 0
  93 static char *
  94 scm_try_path (char *path)
  95 {
  96   FILE *f;
  97   /* fprintf(stderr, "Trying %s\n", path);fflush(stderr); */
  98   if (!path)
  99     return 0L;
 100   SCM_SYSCALL (f = fopen (path, "r");
 101     );
 102   if (f)
 103     {
 104       fclose (f);
 105       return path;
 106     }
 107   free (path);
 108   return 0L;
 109 }
 110
 111 static char *
 112 scm_sep_init_try (char *path, const char *sep, const char *initname)
 113 {
 114   if (path)
 115     path = scm_cat_path (path, sep, 0L);
 116   if (path)
 117     path = scm_cat_path (path, initname, 0L);
 118   return scm_try_path (path);
 119 }
 120 #endif
 121
 122 #ifndef LINE_INCREMENTORS
 123 #define LINE_INCREMENTORS  '\n'
 124 #ifdef MSDOS
 125 #define WHITE_SPACES  ' ':case '\t':case '\r':case '\f':case 26
 126 #else
 127 #define WHITE_SPACES  ' ':case '\t':case '\r':case '\f'
 128 #endif /* def MSDOS */
 129 #endif /* ndef LINE_INCREMENTORS */
 130
 131 #ifndef MAXPATHLEN
 132 #define MAXPATHLEN 80
 133 #endif /* ndef MAXPATHLEN */
 134 #ifndef X_OK
 135 #define X_OK 1
 136 #endif /* ndef X_OK */
 137
 138 char *
 139 scm_find_executable (const char *name)
 140 {
 141   char tbuf[MAXPATHLEN];
 142   int i = 0;
 143   FILE *f;
 144
 145   /* fprintf(stderr, "s_f_e checking access %s ->%d\n", name, access(name, X_OK)); fflush(stderr); */
 146   if (access (name, X_OK))
 147     return 0L;
 148   f = fopen (name, "r");
 149   if (!f)
 150     return 0L;
 151   if ((fgetc (f) == '#') && (fgetc (f) == '!'))
 152     {
 153       while (1)
 154         switch (tbuf[i++] = fgetc (f))
 155           {
 156           case /*WHITE_SPACES */ ' ':
 157           case '\t':
 158           case '\r':
 159           case '\f':
 160           case EOF:
 161             tbuf[--i] = 0;
 162             fclose (f);
 163             return scm_cat_path (0L, tbuf, 0L);
 164           }
 165     }
 166   fclose (f);
 167   return scm_cat_path (0L, name, 0L);
 168 }
 169
 170
 171 /* Read a \nnn-style escape.  We've just read the backslash.  */
 172 static int
 173 script_get_octal (FILE *f)
 174 #define FUNC_NAME "script_get_octal"
 175 {
 176   int i;
 177   int value = 0;
 178
 179   for (i = 0; i < 3; i++)
 180     {
 181       int c = getc (f);
 182       if ('0' <= c && c <= '7')
 183         value = (value * 8) + (c - '0');
 184       else
 185         SCM_MISC_ERROR ("malformed script: bad octal backslash escape",
 186                         SCM_EOL);
 187     }
 188   return value;
 189 }
 190 #undef FUNC_NAME
 191
 192
 193 static int
 194 script_get_backslash (FILE *f)
 195 #define FUNC_NAME "script_get_backslash"
 196 {
 197   int c = getc (f);
 198
 199   switch (c)
 200     {
 201     case 'a': return '\a';
 202     case 'b': return '\b';
 203     case 'f': return '\f';
 204     case 'n': return '\n';
 205     case 'r': return '\r';
 206     case 't': return '\t';
 207     case 'v': return '\v';
 208
 209     case '\\':
 210     case ' ':
 211     case '\t':
 212     case '\n':
 213       return c;
 214
 215     case '0': case '1': case '2': case '3':
 216     case '4': case '5': case '6': case '7':
 217       ungetc (c, f);
 218       return script_get_octal (f);
 219
 220     case EOF:
 221       SCM_MISC_ERROR ("malformed script: backslash followed by EOF", SCM_EOL);
 222       return 0; /* not reached? */
 223
 224     default:
 225       SCM_MISC_ERROR ("malformed script: bad backslash sequence", SCM_EOL);
 226       return 0; /* not reached? */
 227     }
 228 }
 229 #undef FUNC_NAME
 230
 231
 232 static char *
 233 script_read_arg (FILE *f)
 234 #define FUNC_NAME "script_read_arg"
 235 {
 236   int size = 7;
 237   char *buf = malloc (size + 1);
 238   int len = 0;
 239
 240   if (! buf)
 241     return 0;
 242
 243   for (;;)
 244     {
 245       int c = getc (f);
 246       switch (c)
 247         {
 248         case '\\':
 249           c = script_get_backslash (f);
 250           /* The above produces a new character to add to the argument.
 251              Fall through.  */
 252         default:
 253           if (len >= size)
 254             {
 255               size = (size + 1) * 2;
 256               buf = realloc (buf, size);
 257               if (! buf)
 258                 return 0;
 259             }
 260           buf[len++] = c;
 261           break;
 262
 263         case '\n':
 264           /* This may terminate an arg now, but it will terminate the
 265              entire list next time through.  */
 266           ungetc ('\n', f);
 267         case EOF:
 268           if (len == 0)
 269             {
 270               free (buf);
 271               return 0;
 272             }
 273           /* Otherwise, those characters terminate the argument; fall
 274              through.  */
 275         case ' ':
 276           buf[len] = '\0';
 277           return buf;
 278
 279         case '\t':
 280           free (buf);
 281           SCM_MISC_ERROR ("malformed script: TAB in meta-arguments", SCM_EOL);
 282           return 0; /* not reached? */
 283         }
 284     }
 285 }
 286 #undef FUNC_NAME
 287
 288
 289 static int
 290 script_meta_arg_P (char *arg)
 291 {
 292   if ('\\' != arg[0])
 293     return 0L;
 294 #ifdef MSDOS
 295   return !arg[1];
 296 #else
 297   switch (arg[1])
 298     {
 299     case 0:
 300     case '%':
 301     case WHITE_SPACES:
 302       return !0;
 303     default:
 304       return 0L;
 305     }
 306 #endif
 307 }
 308
 309 char **
 310 scm_get_meta_args (int argc, char **argv)
 311 {
 312   int nargc = argc, argi = 1, nargi = 1;
 313   char *narg, **nargv;
 314   if (!(argc > 2 && script_meta_arg_P (argv[1])))
 315     return 0L;
 316   if (!(nargv = (char **) malloc ((1 + nargc) * sizeof (char *))))
 317       return 0L;
 318   nargv[0] = argv[0];
 319   while (((argi + 1) < argc) && (script_meta_arg_P (argv[argi])))
 320     {
 321       FILE *f = fopen (argv[++argi], "r");
 322       if (f)
 323         {
 324           nargc--;              /* to compensate for replacement of '\\' */
 325           while (1)
 326             switch (getc (f))
 327               {
 328               case EOF:
 329                 return 0L;
 330               default:
 331                 continue;
 332               case '\n':
 333                 goto found_args;
 334               }
 335         found_args:
 336           while ((narg = script_read_arg (f)))
 337             if (!(nargv = (char **) realloc (nargv,
 338                                              (1 + ++nargc) * sizeof (char *))))
 339                 return 0L;
 340             else
 341               nargv[nargi++] = narg;
 342           fclose (f);
 343           nargv[nargi++] = argv[argi++];
 344         }
 345     }
 346   while (argi <= argc)
 347     nargv[nargi++] = argv[argi++];
 348   return nargv;
 349 }
 350
 351 int
 352 scm_count_argv (char **argv)
 353 {
 354   int argc = 0;
 355   while (argv[argc])
 356     argc++;
 357   return argc;
 358 }
 359
 360
 361 /* For use in error messages.  */
 362 char *scm_usage_name = 0;
 363
 364 void
 365 scm_shell_usage (int fatal, char *message)
 366 {
 367   if (message)
 368     fprintf (stderr, "%s\n", message);
 369
 370   fprintf (stderr,
 371            "Usage: %s OPTION ...\n"
 372            "Evaluate Scheme code, interactively or from a script.\n"
 373            "\n"
 374            "  -s SCRIPT      load Scheme source code from FILE, and exit\n"
 375            "  -c EXPR        evalute Scheme expression EXPR, and exit\n"
 376            "  --             stop scanning arguments; run interactively\n"
 377            "The above switches stop argument processing, and pass all\n"
 378            "remaining arguments as the value of (command-line).\n"
 379            "\n"
 380            "  -l FILE        load Scheme source code from FILE\n"
 381            "  -e FUNCTION    after reading script, apply FUNCTION to\n"
 382            "                 command line arguments\n"
 383            "  -ds            do -s script at this point\n"
 384            "  --debug        start with debugging evaluator and backtraces\n"
 385            "  -q             inhibit loading of user init file\n"
 386            "  --emacs        enable Emacs protocol (experimental)\n"
 387            "  -h, --help     display this help and exit\n"
 388            "  -v, --version  display version information and exit\n"
 389            "  \\              read arguments from following script lines\n",
 390            scm_usage_name);
 391
 392   if (fatal)
 393     exit (fatal);
 394 }
 395
 396
 397 /* Some symbols used by the command-line compiler.  */
 398 SCM_SYMBOL (sym_load, "load");
 399 SCM_SYMBOL (sym_eval_string, "eval-string");
 400 SCM_SYMBOL (sym_command_line, "command-line");
 401 SCM_SYMBOL (sym_begin, "begin");
 402 SCM_SYMBOL (sym_load_user_init, "load-user-init");
 403 SCM_SYMBOL (sym_top_repl, "top-repl");
 404 SCM_SYMBOL (sym_quit, "quit");
 405
 406
 407 /* Given an array of command-line switches, return a Scheme expression
 408    to carry out the actions specified by the switches.
 409
 410    If you told me this should have been written in Scheme, I'd
 411    probably agree.  I'd say I didn't feel comfortable doing that in
 412    the present system.  You'd say, well, fix the system so you are
 413    comfortable doing that.  I'd agree again.  *shrug*
 414  */
 415
 416 static char guile[] = "guile";
 417
 418 SCM
 419 scm_compile_shell_switches (int argc, char **argv)
 420 {
 421   SCM tail = SCM_EOL;           /* We accumulate the list backwards,
 422                                    and then reverse! it before we
 423                                    return it.  */
 424   SCM do_script = SCM_EOL;      /* The element of the list containing
 425                                    the "load" command, in case we get
 426                                    the "-ds" switch.  */
 427   SCM entry_point = SCM_EOL;    /* for -e switch */
 428   int interactive = 1;          /* Should we go interactive when done? */
 429   int inhibit_user_init = 0;    /* Don't load user init file */
 430   int use_emacs_interface = 0;
 431   int i;
 432   char *argv0 = guile;
 433
 434   if (argc > 0)
 435     {
 436       argv0 = argv[0];
 437       scm_usage_name = strrchr (argv[0], '/');
 438       if (! scm_usage_name)
 439         scm_usage_name = argv[0];
 440       else
 441         scm_usage_name++;
 442     }
 443   if (! scm_usage_name)
 444     scm_usage_name = guile;
 445
 446   for (i = 1; i < argc; i++)
 447     {
 448       if (! strcmp (argv[i], "-s")) /* load script */
 449         {
 450           if (++i >= argc)
 451             scm_shell_usage (1, "missing argument to `-s' switch");
 452
 453           /* If we specified the -ds option, do_script points to the
 454              cdr of an expression like (load #f); we replace the car
 455              (i.e., the #f) with the script name.  */
 456           if (!SCM_NULLP (do_script))
 457             {
 458               SCM_SETCAR (do_script, scm_makfrom0str (argv[i]));
 459               do_script = SCM_EOL;
 460             }
 461           else
 462             /* Construct an application of LOAD to the script name.  */
 463             tail = scm_cons (scm_cons2 (sym_load,
 464                                         scm_makfrom0str (argv[i]),
 465                                         SCM_EOL),
 466                                tail);
 467           argv0 = argv[i];
 468           i++;
 469           interactive = 0;
 470           break;
 471         }
 472
 473       else if (! strcmp (argv[i], "-c")) /* evaluate expr */
 474         {
 475           if (++i >= argc)
 476             scm_shell_usage (1, "missing argument to `-c' switch");
 477           tail = scm_cons (scm_cons2 (sym_eval_string,
 478                                       scm_makfrom0str (argv[i]),
 479                                       SCM_EOL),
 480                            tail);
 481           i++;
 482           interactive = 0;
 483           break;
 484         }
 485
 486       else if (! strcmp (argv[i], "--")) /* end args; go interactive */
 487         {
 488           i++;
 489           break;
 490         }
 491
 492       else if (! strcmp (argv[i], "-l")) /* load a file */
 493         {
 494           if (++i < argc)
 495             tail = scm_cons (scm_cons2 (sym_load,
 496                                         scm_makfrom0str (argv[i]),
 497                                         SCM_EOL),
 498                              tail);
 499           else
 500             scm_shell_usage (1, "missing argument to `-l' switch");
 501         }
 502
 503       else if (! strcmp (argv[i], "-e")) /* entry point */
 504         {
 505           if (++i < argc)
 506             entry_point = gh_symbol2scm (argv[i]);
 507           else
 508             scm_shell_usage (1, "missing argument to `-e' switch");
 509         }
 510
 511       else if (! strcmp (argv[i], "-ds")) /* do script here */
 512         {
 513           /* We put a dummy "load" expression, and let the -s put the
 514              filename in.  */
 515           if (!SCM_NULLP (do_script))
 516             scm_shell_usage (1, "the -ds switch may only be specified once");
 517           do_script = scm_cons (SCM_BOOL_F, SCM_EOL);
 518           tail = scm_cons (scm_cons (sym_load, do_script),
 519                            tail);
 520         }
 521
 522       else if (! strcmp (argv[i], "--debug")) /* debug eval + backtraces */
 523         {
 524           SCM_DEVAL_P = 1;
 525           SCM_BACKTRACE_P = 1;
 526           SCM_RECORD_POSITIONS_P = 1;
 527           SCM_RESET_DEBUG_MODE;
 528         }
 529
 530       else if (! strcmp (argv[i], "--emacs")) /* use emacs protocol */
 531         use_emacs_interface = 1;
 532
 533       else if (! strcmp (argv[i], "-q")) /* don't load user init */
 534         inhibit_user_init = 1;
 535
 536       else if (! strcmp (argv[i], "-h")
 537                || ! strcmp (argv[i], "--help"))
 538         {
 539           scm_shell_usage (0, 0);
 540           exit (0);
 541         }
 542
 543       else if (! strcmp (argv[i], "-v")
 544                || ! strcmp (argv[i], "--version"))
 545         {
 546           /* Print version number.  */
 547           printf ("Guile %s\n"
 548                   "Copyright (c) 1995, 1996, 1997, 2000 Free Software Foundation\n"
 549                   "Guile may be distributed under the terms of the GNU General Public Licence;\n"
 550                   "certain other uses are permitted as well.  For details, see the file\n"
 551                   "`COPYING', which is included in the Guile distribution.\n"
 552                   "There is no warranty, to the extent permitted by law.\n",
 553                   SCM_STRING_CHARS (scm_version ()));
 554           exit (0);
 555         }
 556
 557       else
 558         {
 559           fprintf (stderr, "%s: Unrecognized switch `%s'\n",
 560                    scm_usage_name, argv[i]);
 561           scm_shell_usage (1, 0);
 562         }
 563     }
 564
 565   /* Check to make sure the -ds got a -s. */
 566   if (!SCM_NULLP (do_script))
 567     scm_shell_usage (1, "the `-ds' switch requires the use of `-s' as well");
 568
 569   /* Make any remaining arguments available to the
 570      script/command/whatever.  */
 571   scm_set_program_arguments (argc ? argc - i : 0, argv + i, argv0);
 572
 573   /* If the --emacs switch was set, now is when we process it.  */
 574   scm_c_define ("use-emacs-interface", SCM_BOOL (use_emacs_interface));
 575
 576   /* Handle the `-e' switch, if it was specified.  */
 577   if (!SCM_NULLP (entry_point))
 578     tail = scm_cons (scm_cons2 (entry_point,
 579                                 scm_cons (sym_command_line, SCM_EOL),
 580                                 SCM_EOL),
 581                        tail);
 582
 583   /* If we didn't end with a -c or a -s, start the repl.  */
 584   if (interactive)
 585     {
 586       tail = scm_cons (scm_cons (sym_top_repl, SCM_EOL), tail);
 587     }
 588   else
 589     {
 590       /* After doing all the other actions prescribed by the command line,
 591          quit.  */
 592       tail = scm_cons (scm_cons (sym_quit, SCM_EOL),
 593                        tail);
 594       /* Allow asyncs (signal handlers etc.) to be run.  */
 595       scm_mask_ints = 0;
 596     }
 597
 598   /* After the following line, actions will be added to the front. */
 599   tail = scm_reverse_x (tail, SCM_UNDEFINED);
 600
 601   /* If we didn't end with a -c or a -s and didn't supply a -q, load
 602      the user's customization file.  */
 603   if (interactive && !inhibit_user_init)
 604     {
 605       tail = scm_cons (scm_cons (sym_load_user_init, SCM_EOL), tail);
 606     }
 607
 608   {
 609     SCM val = scm_cons (sym_begin, tail);
 610
 611 #if 0
 612     scm_write (val, SCM_UNDEFINED);
 613     scm_newline (SCM_UNDEFINED);
 614 #endif
 615
 616     return val;
 617   }
 618 }
 619
 620
 621 void
 622 scm_shell (int argc, char **argv)
 623 {
 624   /* If present, add SCSH-style meta-arguments from the top of the
 625      script file to the argument vector.  See the SCSH manual: "The
 626      meta argument" for more details.  */
 627   {
 628     char **new_argv = scm_get_meta_args (argc, argv);
 629
 630     if (new_argv)
 631       {
 632         argv = new_argv;
 633         argc = scm_count_argv (new_argv);
 634       }
 635   }
 636
 637   exit (scm_exit_status (scm_eval_x (scm_compile_shell_switches (argc, argv),
 638                                      scm_the_root_module ())));
 639 }
 640
 641
 642 void
 643 scm_init_script ()
 644 {
 645 #ifndef SCM_MAGIC_SNARFER
 646 #include "libguile/script.x"
 647 #endif
 648 }
 649
 650 /*
 651   Local Variables:
 652   c-file-style: "gnu"
 653   End:
 654 */