gdb/main.c

   1 /* Top level `main' program for GDB, the GNU debugger.
   2    Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992
   3    Free Software Foundation, Inc.
   4
   5 This file is part of GDB.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 #include "defs.h"
  22 #include "gdbcmd.h"
  23 #include "call-cmds.h"
  24 #include "symtab.h"
  25 #include "inferior.h"
  26 #include "signals.h"
  27 #include "target.h"
  28 #include "breakpoint.h"
  29 #include "gdbtypes.h"
  30 #include "expression.h"
  31 #include "language.h"
  32
  33 #include "getopt.h"
  34
  35 /* readline include files */
  36 #include "readline.h"
  37 #include "history.h"
  38
  39 /* readline defines this.  */
  40 #undef savestring
  41
  42 #ifdef USG
  43 #include <sys/types.h>
  44 #include <unistd.h>
  45 #endif
  46
  47 #include <string.h>
  48 #ifndef NO_SYS_FILE
  49 #include <sys/file.h>
  50 #endif
  51 #include <setjmp.h>
  52 #include <sys/param.h>
  53 #include <sys/stat.h>
  54 #include <ctype.h>
  55
  56 #ifdef SET_STACK_LIMIT_HUGE
  57 #include <sys/time.h>
  58 #include <sys/resource.h>
  59
  60 int original_stack_limit;
  61 #endif
  62
  63 /* Prototypes for local functions */
  64
  65 static char *
  66 symbol_completion_function PARAMS ((char *, int));
  67
  68 static void
  69 command_loop PARAMS ((void));
  70
  71 static void
  72 command_loop_marker PARAMS ((int));
  73
  74 static void
  75 print_gdb_version PARAMS ((FILE *));
  76
  77 static void
  78 quit_command PARAMS ((char *, int));
  79
  80 static void
  81 initialize_main PARAMS ((void));
  82
  83 static void
  84 initialize_history PARAMS ((void));
  85
  86 static void
  87 initialize_cmd_lists PARAMS ((void));
  88
  89 static void
  90 float_handler PARAMS ((int));
  91
  92 static void
  93 source_command PARAMS ((char *, int));
  94
  95 static void
  96 cd_command PARAMS ((char *, int));
  97
  98 static void
  99 print_gnu_advertisement PARAMS ((void));
 100
 101 static void
 102 init_signals PARAMS ((void));
 103
 104 static void
 105 read_command_file PARAMS ((FILE *));
 106
 107 static void
 108 set_verbose PARAMS ((char *, int, struct cmd_list_element *));
 109
 110 static void
 111 show_history PARAMS ((char *, int));
 112
 113 static void
 114 set_history PARAMS ((char *, int));
 115
 116 static void
 117 set_history_size_command PARAMS ((char *, int, struct cmd_list_element *));
 118
 119 static void
 120 show_commands PARAMS ((char *, int));
 121
 122 static void
 123 echo_command PARAMS ((char *, int));
 124
 125 static void
 126 pwd_command PARAMS ((char *, int));
 127
 128 static void
 129 show_version PARAMS ((char *, int));
 130
 131 static void
 132 document_command PARAMS ((char *, int));
 133
 134 static void
 135 define_command PARAMS ((char *, int));
 136
 137 static void
 138 validate_comname PARAMS ((char *));
 139
 140 static void
 141 help_command PARAMS ((char *, int));
 142
 143 static void
 144 show_command PARAMS ((char *, int));
 145
 146 static void
 147 info_command PARAMS ((char *, int));
 148
 149 static void
 150 do_nothing PARAMS ((int));
 151
 152 static int
 153 quit_cover PARAMS ((char *));
 154
 155 static void
 156 disconnect PARAMS ((int));
 157
 158 static void
 159 source_cleanup PARAMS ((FILE *));
 160
 161 /* If this definition isn't overridden by the header files, assume
 162    that isatty and fileno exist on this system.  */
 163 #ifndef ISATTY
 164 #define ISATTY(FP)      (isatty (fileno (FP)))
 165 #endif
 166
 167 /* Initialization file name for gdb.  This is overridden in some configs.  */
 168
 169 #ifndef GDBINIT_FILENAME
 170 #define GDBINIT_FILENAME        ".gdbinit"
 171 #endif
 172 static char gdbinit[] = GDBINIT_FILENAME;
 173 static int inhibit_gdbinit = 0;
 174
 175 #define ALL_CLEANUPS    ((struct cleanup *)0)
 176
 177 /* Version number of GDB, as a string.  */
 178
 179 extern char *version;
 180
 181 /* Message to be printed before the error message, when an error occurs.  */
 182
 183 extern char *error_pre_print;
 184
 185 /* Message to be printed before the warning message, when a warning occurs.  */
 186
 187 extern char *warning_pre_print;
 188
 189 extern char lang_frame_mismatch_warn[];         /* language.c */
 190
 191 /* Whether GDB's stdin is on a terminal.  */
 192
 193 extern int gdb_has_a_terminal;                  /* inflow.c */
 194
 195 /* Flag for whether we want all the "from_tty" gubbish printed.  */
 196
 197 int caution = 1;                        /* Default is yes, sigh. */
 198
 199 /*
 200  * Define all cmd_list_element's
 201  */
 202
 203 /* Chain containing all defined commands.  */
 204
 205 struct cmd_list_element *cmdlist;
 206
 207 /* Chain containing all defined info subcommands.  */
 208
 209 struct cmd_list_element *infolist;
 210
 211 /* Chain containing all defined enable subcommands. */
 212
 213 struct cmd_list_element *enablelist;
 214
 215 /* Chain containing all defined disable subcommands. */
 216
 217 struct cmd_list_element *disablelist;
 218
 219 /* Chain containing all defined delete subcommands. */
 220
 221 struct cmd_list_element *deletelist;
 222
 223 /* Chain containing all defined "enable breakpoint" subcommands. */
 224
 225 struct cmd_list_element *enablebreaklist;
 226
 227 /* Chain containing all defined set subcommands */
 228
 229 struct cmd_list_element *setlist;
 230
 231 /* Chain containing all defined unset subcommands */
 232
 233 struct cmd_list_element *unsetlist;
 234
 235 /* Chain containing all defined show subcommands.  */
 236
 237 struct cmd_list_element *showlist;
 238
 239 /* Chain containing all defined \"set history\".  */
 240
 241 struct cmd_list_element *sethistlist;
 242
 243 /* Chain containing all defined \"show history\".  */
 244
 245 struct cmd_list_element *showhistlist;
 246
 247 /* Chain containing all defined \"unset history\".  */
 248
 249 struct cmd_list_element *unsethistlist;
 250
 251 /* Chain containing all defined maintenance subcommands. */
 252
 253 #if MAINTENANCE_CMDS
 254 struct cmd_list_element *maintenancelist;
 255 #endif
 256
 257 /* Chain containing all defined "maintenance info" subcommands. */
 258
 259 #if MAINTENANCE_CMDS
 260 struct cmd_list_element *maintenanceinfolist;
 261 #endif
 262
 263 /* Chain containing all defined "maintenance print" subcommands. */
 264
 265 #if MAINTENANCE_CMDS
 266 struct cmd_list_element *maintenanceprintlist;
 267 #endif
 268
 269 struct cmd_list_element *setprintlist;
 270
 271 struct cmd_list_element *showprintlist;
 272
 273 struct cmd_list_element *setchecklist;
 274
 275 struct cmd_list_element *showchecklist;
 276
 277 /* stdio stream that command input is being read from.  */
 278
 279 FILE *instream;
 280
 281 /* Current working directory.  */
 282
 283 char *current_directory;
 284
 285 /* The directory name is actually stored here (usually).  */
 286 static char dirbuf[1024];
 287
 288 /* Function to call before reading a command, if nonzero.
 289    The function receives two args: an input stream,
 290    and a prompt string.  */
 291
 292 void (*window_hook) PARAMS ((FILE *, char *));
 293
 294 extern int frame_file_full_name;
 295 extern int mapped_symbol_files;
 296 extern int readnow_symbol_files;
 297
 298 int epoch_interface;
 299 int xgdb_verbose;
 300
 301 /* gdb prints this when reading a command interactively */
 302 static char *prompt;
 303
 304 /* Buffer used for reading command lines, and the size
 305    allocated for it so far.  */
 306
 307 char *line;
 308 int linesize = 100;
 309
 310 /* Baud rate specified for talking to serial target systems.  Default
 311    is left as a zero pointer, so targets can choose their own defaults.  */
 312
 313 char *baud_rate;
 314
 315 /* Signal to catch ^Z typed while reading a command: SIGTSTP or SIGCONT.  */
 316
 317 #ifndef STOP_SIGNAL
 318 #ifdef SIGTSTP
 319 #define STOP_SIGNAL SIGTSTP
 320 static void stop_sig PARAMS ((int));
 321 #endif
 322 #endif
 323
 324 /* Some System V have job control but not sigsetmask(). */
 325 #if !defined (HAVE_SIGSETMASK)
 326 #define HAVE_SIGSETMASK !defined (USG)
 327 #endif
 328
 329 #if 0 == (HAVE_SIGSETMASK)
 330 #define sigsetmask(n)
 331 #endif
 332 \f
 333 /* This is how `error' returns to command level.  */
 334
 335 jmp_buf to_top_level;
 336
 337 NORETURN void
 338 return_to_top_level ()
 339 {
 340   quit_flag = 0;
 341   immediate_quit = 0;
 342   bpstat_clear_actions(stop_bpstat);    /* Clear queued breakpoint commands */
 343   disable_current_display ();
 344   do_cleanups (ALL_CLEANUPS);
 345   (NORETURN void) longjmp (to_top_level, 1);
 346 }
 347
 348 /* Call FUNC with arg ARGS, catching any errors.
 349    If there is no error, return the value returned by FUNC.
 350    If there is an error, print ERRSTRING, print the specific error message,
 351                          then return zero.  */
 352
 353 int
 354 catch_errors (func, args, errstring)
 355      int (*func) PARAMS ((char *));
 356      char *args;
 357      char *errstring;
 358 {
 359   jmp_buf saved;
 360   int val;
 361   struct cleanup *saved_cleanup_chain;
 362   char *saved_error_pre_print;
 363
 364   saved_cleanup_chain = save_cleanups ();
 365   saved_error_pre_print = error_pre_print;
 366
 367   memcpy ((char *)saved, (char *)to_top_level, sizeof (jmp_buf));
 368   error_pre_print = errstring;
 369
 370   if (setjmp (to_top_level) == 0)
 371     val = (*func) (args);
 372   else
 373     val = 0;
 374
 375   restore_cleanups (saved_cleanup_chain);
 376
 377   error_pre_print = saved_error_pre_print;
 378   memcpy ((char *)to_top_level, (char *)saved, sizeof (jmp_buf));
 379   return val;
 380 }
 381
 382 /* Handler for SIGHUP.  */
 383
 384 static void
 385 disconnect (signo)
 386 int signo;
 387 {
 388   catch_errors (quit_cover, NULL,
 389                 "Could not kill the program being debugged");
 390   signal (SIGHUP, SIG_DFL);
 391   kill (getpid (), SIGHUP);
 392 }
 393
 394 /* Just a little helper function for disconnect().  */
 395
 396 static int
 397 quit_cover (s)
 398 char *s;
 399 {
 400   caution = 0;          /* Throw caution to the wind -- we're exiting.
 401                            This prevents asking the user dumb questions.  */
 402   quit_command((char *)0, 0);
 403   return 0;
 404 }
 405 \f
 406 /* Clean up on error during a "source" command (or execution of a
 407    user-defined command).  */
 408
 409 static void
 410 source_cleanup (stream)
 411      FILE *stream;
 412 {
 413   /* Restore the previous input stream.  */
 414   instream = stream;
 415 }
 416
 417 /* Read commands from STREAM.  */
 418 static void
 419 read_command_file (stream)
 420      FILE *stream;
 421 {
 422   struct cleanup *cleanups;
 423
 424   cleanups = make_cleanup (source_cleanup, instream);
 425   instream = stream;
 426   command_loop ();
 427   do_cleanups (cleanups);
 428 }
 429 \f
 430 int
 431 main (argc, argv)
 432      int argc;
 433      char **argv;
 434 {
 435   int count;
 436   static int quiet = 0;
 437   static int batch = 0;
 438
 439   /* Pointers to various arguments from command line.  */
 440   char *symarg = NULL;
 441   char *execarg = NULL;
 442   char *corearg = NULL;
 443   char *cdarg = NULL;
 444   char *ttyarg = NULL;
 445
 446   /* Pointers to all arguments of +command option.  */
 447   char **cmdarg;
 448   /* Allocated size of cmdarg.  */
 449   int cmdsize;
 450   /* Number of elements of cmdarg used.  */
 451   int ncmd;
 452
 453   /* Indices of all arguments of +directory option.  */
 454   char **dirarg;
 455   /* Allocated size.  */
 456   int dirsize;
 457   /* Number of elements used.  */
 458   int ndir;
 459
 460   struct stat homebuf, cwdbuf;
 461   char *homedir, *homeinit;
 462
 463   register int i;
 464
 465   /* This needs to happen before the first use of malloc.  */
 466   init_malloc ((PTR) NULL);
 467
 468 #if defined (ALIGN_STACK_ON_STARTUP)
 469   i = (int) &count & 0x3;
 470   if (i != 0)
 471     alloca (4 - i);
 472 #endif
 473
 474   /* If error() is called from initialization code, just exit */
 475   if (setjmp (to_top_level)) {
 476     exit(1);
 477   }
 478
 479   cmdsize = 1;
 480   cmdarg = (char **) xmalloc (cmdsize * sizeof (*cmdarg));
 481   ncmd = 0;
 482   dirsize = 1;
 483   dirarg = (char **) xmalloc (dirsize * sizeof (*dirarg));
 484   ndir = 0;
 485
 486   quit_flag = 0;
 487   line = (char *) xmalloc (linesize);
 488   line[0] = '\0';               /* Terminate saved (now empty) cmd line */
 489   instream = stdin;
 490
 491   getcwd (dirbuf, sizeof (dirbuf));
 492   current_directory = dirbuf;
 493
 494 #ifdef SET_STACK_LIMIT_HUGE
 495   {
 496     struct rlimit rlim;
 497
 498     /* Set the stack limit huge so that alloca (particularly stringtab
 499      * in dbxread.c) does not fail. */
 500     getrlimit (RLIMIT_STACK, &rlim);
 501     original_stack_limit = rlim.rlim_cur;
 502     rlim.rlim_cur = rlim.rlim_max;
 503     setrlimit (RLIMIT_STACK, &rlim);
 504   }
 505 #endif /* SET_STACK_LIMIT_HUGE */
 506
 507   /* Parse arguments and options.  */
 508   {
 509     int c;
 510     static int print_help;
 511     /* When var field is 0, use flag field to record the equivalent
 512        short option (or arbitrary numbers starting at 10 for those
 513        with no equivalent).  */
 514     static struct option long_options[] =
 515       {
 516         {"readnow", no_argument, &readnow_symbol_files, 1},
 517         {"r", no_argument, &readnow_symbol_files, 1},
 518         {"mapped", no_argument, &mapped_symbol_files, 1},
 519         {"m", no_argument, &mapped_symbol_files, 1},
 520         {"quiet", no_argument, &quiet, 1},
 521         {"q", no_argument, &quiet, 1},
 522         {"silent", no_argument, &quiet, 1},
 523         {"nx", no_argument, &inhibit_gdbinit, 1},
 524         {"n", no_argument, &inhibit_gdbinit, 1},
 525         {"batch", no_argument, &batch, 1},
 526         {"epoch", no_argument, &epoch_interface, 1},
 527         {"fullname", no_argument, &frame_file_full_name, 1},
 528         {"f", no_argument, &frame_file_full_name, 1},
 529         {"help", no_argument, &print_help, 1},
 530         {"se", required_argument, 0, 10},
 531         {"symbols", required_argument, 0, 's'},
 532         {"s", required_argument, 0, 's'},
 533         {"exec", required_argument, 0, 'e'},
 534         {"e", required_argument, 0, 'e'},
 535         {"core", required_argument, 0, 'c'},
 536         {"c", required_argument, 0, 'c'},
 537         {"command", required_argument, 0, 'x'},
 538         {"x", required_argument, 0, 'x'},
 539         {"directory", required_argument, 0, 'd'},
 540         {"cd", required_argument, 0, 11},
 541         {"tty", required_argument, 0, 't'},
 542         {"baud", required_argument, 0, 'b'},
 543         {"b", required_argument, 0, 'b'},
 544 /* Allow machine descriptions to add more options... */
 545 #ifdef ADDITIONAL_OPTIONS
 546         ADDITIONAL_OPTIONS
 547 #endif
 548         {0, no_argument, 0, 0},
 549       };
 550
 551     while (1)
 552       {
 553         int option_index;
 554
 555         c = getopt_long_only (argc, argv, "",
 556                               long_options, &option_index);
 557         if (c == EOF)
 558           break;
 559
 560         /* Long option that takes an argument.  */
 561         if (c == 0 && long_options[option_index].flag == 0)
 562           c = long_options[option_index].val;
 563
 564         switch (c)
 565           {
 566           case 0:
 567             /* Long option that just sets a flag.  */
 568             break;
 569           case 10:
 570             symarg = optarg;
 571             execarg = optarg;
 572             break;
 573           case 11:
 574             cdarg = optarg;
 575             break;
 576           case 's':
 577             symarg = optarg;
 578             break;
 579           case 'e':
 580             execarg = optarg;
 581             break;
 582           case 'c':
 583             corearg = optarg;
 584             break;
 585           case 'x':
 586             cmdarg[ncmd++] = optarg;
 587             if (ncmd >= cmdsize)
 588               {
 589                 cmdsize *= 2;
 590                 cmdarg = (char **) xrealloc ((char *)cmdarg,
 591                                              cmdsize * sizeof (*cmdarg));
 592               }
 593             break;
 594           case 'd':
 595             dirarg[ndir++] = optarg;
 596             if (ndir >= dirsize)
 597               {
 598                 dirsize *= 2;
 599                 dirarg = (char **) xrealloc ((char *)dirarg,
 600                                              dirsize * sizeof (*dirarg));
 601               }
 602             break;
 603           case 't':
 604             ttyarg = optarg;
 605             break;
 606           case 'q':
 607             quiet = 1;
 608             break;
 609           case 'b':
 610             baud_rate = optarg;
 611             break;
 612 #ifdef ADDITIONAL_OPTION_CASES
 613           ADDITIONAL_OPTION_CASES
 614 #endif
 615           case '?':
 616             fprintf (stderr,
 617                      "Use `%s --help' for a complete list of options.\n",
 618                      argv[0]);
 619             exit (1);
 620           }
 621       }
 622
 623     if (print_help)
 624       {
 625         print_gdb_version(stderr);
 626         fputs ("\n\
 627 This is the GNU debugger.  Usage:\n\
 628     gdb [options] [executable-file [core-file or process-id]]\n\
 629 Options:\n\
 630   -help             Print this message.\n\
 631   -quiet            Do not print version number on startup.\n\
 632   -fullname         Output information used by emacs-GDB interface.\n\
 633   -epoch            Output information used by epoch emacs-GDB interface.\n\
 634   -batch            Exit after processing options.\n\
 635   -nx               Do not read .gdbinit file.\n\
 636   -tty=TTY          Use TTY for input/output by the program being debugged.\n\
 637   -cd=DIR           Change current directory to DIR.\n\
 638   -directory=DIR    Search for source files in DIR.\n\
 639   -command=FILE     Execute GDB commands from FILE.\n\
 640   -symbols=SYMFILE  Read symbols from SYMFILE.\n\
 641   -exec=EXECFILE    Use EXECFILE as the executable.\n\
 642   -se=FILE          Use FILE as symbol file and executable file.\n\
 643   -core=COREFILE    Analyze the core dump COREFILE.\n\
 644   -b BAUDRATE       Set serial port baud rate used for remote debugging.\n\
 645   -mapped           Use mapped symbol files if supported on this system.\n\
 646   -readnow          Fully read symbol files on first access.\n\
 647 ", stderr);
 648 #ifdef ADDITIONAL_OPTION_HELP
 649         fputs (ADDITIONAL_OPTION_HELP, stderr);
 650 #endif
 651         fputs ("\n\
 652 For more information, type \"help\" from within GDB, or consult the\n\
 653 GDB manual (available as on-line info or a printed manual).\n", stderr);
 654         /* Exiting after printing this message seems like
 655            the most useful thing to do.  */
 656         exit (0);
 657       }
 658
 659     /* OK, that's all the options.  The other arguments are filenames.  */
 660     count = 0;
 661     for (; optind < argc; optind++)
 662       switch (++count)
 663         {
 664         case 1:
 665           symarg = argv[optind];
 666           execarg = argv[optind];
 667           break;
 668         case 2:
 669           corearg = argv[optind];
 670           break;
 671         case 3:
 672           fprintf (stderr,
 673                    "Excess command line arguments ignored. (%s%s)\n",
 674                    argv[optind], (optind == argc - 1) ? "" : " ...");
 675           break;
 676         }
 677     if (batch)
 678       quiet = 1;
 679   }
 680
 681   /* Run the init function of each source file */
 682
 683   initialize_cmd_lists ();      /* This needs to be done first */
 684   initialize_all_files ();
 685   initialize_main ();           /* But that omits this file!  Do it now */
 686   init_signals ();
 687
 688   if (!quiet)
 689     {
 690       /* Print all the junk at the top, with trailing "..." if we are about
 691          to read a symbol file (possibly slowly).  */
 692       print_gnu_advertisement ();
 693       print_gdb_version (stdout);
 694       if (symarg)
 695         printf_filtered ("..");
 696       wrap_here("");
 697       fflush (stdout);          /* Force to screen during slow operations */
 698     }
 699
 700   error_pre_print = "\n\n";
 701   /* We may get more than one warning, don't double space all of them... */
 702   warning_pre_print = "\nwarning: ";
 703
 704   /* We need a default language for parsing expressions, so simple things like
 705      "set width 0" won't fail if no language is explicitly set in a config file
 706      or implicitly set by reading an executable during startup. */
 707   set_language (language_c);
 708   expected_language = current_language; /* don't warn about the change.  */
 709
 710   /* Read and execute $HOME/.gdbinit file, if it exists.  This is done
 711      *before* all the command line arguments are processed; it sets
 712      global parameters, which are independent of what file you are
 713      debugging or what directory you are in.  */
 714   homedir = getenv ("HOME");
 715   if (homedir)
 716     {
 717       homeinit = (char *) alloca (strlen (getenv ("HOME")) +
 718                                   strlen (gdbinit) + 10);
 719       strcpy (homeinit, getenv ("HOME"));
 720       strcat (homeinit, "/");
 721       strcat (homeinit, gdbinit);
 722       if (!inhibit_gdbinit && access (homeinit, R_OK) == 0)
 723         {
 724           if (!setjmp (to_top_level))
 725             source_command (homeinit, 0);
 726         }
 727       do_cleanups (ALL_CLEANUPS);
 728
 729       /* Do stats; no need to do them elsewhere since we'll only
 730          need them if homedir is set.  Make sure that they are
 731          zero in case one of them fails (this guarantees that they
 732          won't match if either exists).  */
 733
 734       memset (&homebuf, 0, sizeof (struct stat));
 735       memset (&cwdbuf, 0, sizeof (struct stat));
 736
 737       stat (homeinit, &homebuf);
 738       stat (gdbinit, &cwdbuf); /* We'll only need this if
 739                                        homedir was set.  */
 740     }
 741
 742   /* Now perform all the actions indicated by the arguments.  */
 743   if (cdarg != NULL)
 744     {
 745       if (!setjmp (to_top_level))
 746         {
 747           cd_command (cdarg, 0);
 748           init_source_path ();
 749         }
 750     }
 751   do_cleanups (ALL_CLEANUPS);
 752
 753   for (i = 0; i < ndir; i++)
 754     if (!setjmp (to_top_level))
 755       directory_command (dirarg[i], 0);
 756   free ((PTR)dirarg);
 757   do_cleanups (ALL_CLEANUPS);
 758
 759   if (execarg != NULL
 760       && symarg != NULL
 761       && STREQ (execarg, symarg))
 762     {
 763       /* The exec file and the symbol-file are the same.  If we can't open
 764          it, better only print one error message.  */
 765       if (!setjmp (to_top_level))
 766         {
 767           exec_file_command (execarg, !batch);
 768           symbol_file_command (symarg, 0);
 769         }
 770     }
 771   else
 772     {
 773       if (execarg != NULL)
 774         if (!setjmp (to_top_level))
 775           exec_file_command (execarg, !batch);
 776       if (symarg != NULL)
 777         if (!setjmp (to_top_level))
 778           symbol_file_command (symarg, 0);
 779     }
 780   do_cleanups (ALL_CLEANUPS);
 781
 782   /* After the symbol file has been read, print a newline to get us
 783      beyond the copyright line...  But errors should still set off
 784      the error message with a (single) blank line.  */
 785   if (!quiet)
 786     printf_filtered ("\n");
 787   error_pre_print = "\n";
 788   warning_pre_print = "\nwarning: ";
 789
 790   if (corearg != NULL)
 791     if (!setjmp (to_top_level))
 792       core_file_command (corearg, !batch);
 793     else if (isdigit (corearg[0]) && !setjmp (to_top_level))
 794       attach_command (corearg, !batch);
 795   do_cleanups (ALL_CLEANUPS);
 796
 797   if (ttyarg != NULL)
 798     if (!setjmp (to_top_level))
 799       tty_command (ttyarg, !batch);
 800   do_cleanups (ALL_CLEANUPS);
 801
 802 #ifdef ADDITIONAL_OPTION_HANDLER
 803   ADDITIONAL_OPTION_HANDLER;
 804 #endif
 805
 806   /* Error messages should no longer be distinguished with extra output. */
 807   error_pre_print = 0;
 808   warning_pre_print = "warning: ";
 809
 810   /* Read the .gdbinit file in the current directory, *if* it isn't
 811      the same as the $HOME/.gdbinit file (it should exist, also).  */
 812
 813   if (!homedir
 814       || memcmp ((char *) &homebuf, (char *) &cwdbuf, sizeof (struct stat)))
 815     if (!inhibit_gdbinit && access (gdbinit, R_OK) == 0)
 816       {
 817         if (!setjmp (to_top_level))
 818           source_command (gdbinit, 0);
 819       }
 820   do_cleanups (ALL_CLEANUPS);
 821
 822   for (i = 0; i < ncmd; i++)
 823     {
 824       if (!setjmp (to_top_level))
 825         {
 826           if (cmdarg[i][0] == '-' && cmdarg[i][1] == '\0')
 827             read_command_file (stdin);
 828           else
 829             source_command (cmdarg[i], !batch);
 830           do_cleanups (ALL_CLEANUPS);
 831         }
 832     }
 833   free ((PTR)cmdarg);
 834
 835   /* Read in the old history after all the command files have been read. */
 836   initialize_history();
 837
 838   if (batch)
 839     {
 840       /* We have hit the end of the batch file.  */
 841       exit (0);
 842     }
 843
 844   /* Do any host- or target-specific hacks.  This is used for i960 targets
 845      to force the user to set a nindy target and spec its parameters.  */
 846
 847 #ifdef BEFORE_MAIN_LOOP_HOOK
 848   BEFORE_MAIN_LOOP_HOOK;
 849 #endif
 850
 851   /* The command loop.  */
 852
 853   while (1)
 854     {
 855       if (!setjmp (to_top_level))
 856         {
 857           do_cleanups (ALL_CLEANUPS);           /* Do complete cleanup */
 858           command_loop ();
 859           quit_command ((char *)0, instream == stdin);
 860         }
 861     }
 862   /* No exit -- exit is through quit_command.  */
 863 }
 864
 865 void
 866 execute_user_command (c, args)
 867      struct cmd_list_element *c;
 868      char *args;
 869 {
 870   register struct command_line *cmdlines;
 871   struct cleanup *old_chain;
 872
 873   if (args)
 874     error ("User-defined commands cannot take arguments.");
 875
 876   cmdlines = c->user_commands;
 877   if (cmdlines == 0)
 878     /* Null command */
 879     return;
 880
 881   /* Set the instream to 0, indicating execution of a
 882      user-defined function.  */
 883   old_chain = make_cleanup (source_cleanup, instream);
 884   instream = (FILE *) 0;
 885   while (cmdlines)
 886     {
 887       execute_command (cmdlines->line, 0);
 888       cmdlines = cmdlines->next;
 889     }
 890   do_cleanups (old_chain);
 891 }
 892
 893 /* Execute the line P as a command.
 894    Pass FROM_TTY as second argument to the defining function.  */
 895
 896 void
 897 execute_command (p, from_tty)
 898      char *p;
 899      int from_tty;
 900 {
 901   register struct cmd_list_element *c;
 902   register enum language flang;
 903   static int warned = 0;
 904
 905   free_all_values ();
 906
 907   /* This can happen when command_line_input hits end of file.  */
 908   if (p == NULL)
 909       return;
 910
 911   while (*p == ' ' || *p == '\t') p++;
 912   if (*p)
 913     {
 914       char *arg;
 915
 916       c = lookup_cmd (&p, cmdlist, "", 0, 1);
 917       /* Pass null arg rather than an empty one.  */
 918       arg = *p ? p : 0;
 919
 920       /* If this command has been hooked, run the hook first. */
 921       if (c->hook)
 922         execute_user_command (c->hook, (char *)0);
 923
 924       if (c->class == class_user)
 925         execute_user_command (c, arg);
 926       else if (c->type == set_cmd || c->type == show_cmd)
 927         do_setshow_command (arg, from_tty & caution, c);
 928       else if (c->function.cfunc == NO_FUNCTION)
 929         error ("That is not a command, just a help topic.");
 930       else
 931         (*c->function.cfunc) (arg, from_tty & caution);
 932    }
 933
 934   /* Tell the user if the language has changed (except first time).  */
 935   if (current_language != expected_language)
 936   {
 937     if (language_mode == language_mode_auto) {
 938       language_info (1);        /* Print what changed.  */
 939     }
 940     warned = 0;
 941   }
 942
 943   /* Warn the user if the working language does not match the
 944      language of the current frame.  Only warn the user if we are
 945      actually running the program, i.e. there is a stack. */
 946   /* FIXME:  This should be cacheing the frame and only running when
 947      the frame changes.  */
 948   if (target_has_stack)
 949   {
 950     flang = get_frame_language ();
 951     if (!warned
 952         && flang != language_unknown
 953         && flang != current_language->la_language)
 954     {
 955       printf_filtered ("%s\n", lang_frame_mismatch_warn);
 956       warned = 1;
 957     }
 958   }
 959 }
 960
 961 /* ARGSUSED */
 962 static void
 963 command_loop_marker (foo)
 964      int foo;
 965 {
 966 }
 967
 968 /* Read commands from `instream' and execute them
 969    until end of file or error reading instream.  */
 970 static void
 971 command_loop ()
 972 {
 973   struct cleanup *old_chain;
 974   char *command;
 975   int stdin_is_tty = ISATTY (stdin);
 976
 977   while (!feof (instream))
 978     {
 979       if (window_hook && instream == stdin)
 980         (*window_hook) (instream, prompt);
 981
 982       quit_flag = 0;
 983       if (instream == stdin && stdin_is_tty)
 984         reinitialize_more_filter ();
 985       old_chain = make_cleanup (command_loop_marker, 0);
 986       command = command_line_input (instream == stdin ? prompt : (char *) NULL,
 987                                       instream == stdin);
 988       if (command == 0)
 989         return;
 990       execute_command (command, instream == stdin);
 991       /* Do any commands attached to breakpoint we stopped at.  */
 992       bpstat_do_actions (&stop_bpstat);
 993       do_cleanups (old_chain);
 994     }
 995 }
 996 \f
 997 /* Commands call this if they do not want to be repeated by null lines.  */
 998
 999 void
1000 dont_repeat ()
1001 {
1002   /* If we aren't reading from standard input, we are saving the last
1003      thing read from stdin in line and don't want to delete it.  Null lines
1004      won't repeat here in any case.  */
1005   if (instream == stdin)
1006     *line = 0;
1007 }
1008 \f
1009 /* Read a line from the stream "instream" without command line editing.
1010
1011    It prints PRROMPT once at the start.
1012    Action is compatible with "readline", e.g. space for the result is
1013    malloc'd and should be freed by the caller.
1014
1015    A NULL return means end of file.  */
1016 char *
1017 gdb_readline (prrompt)
1018      char *prrompt;
1019 {
1020   int c;
1021   char *result;
1022   int input_index = 0;
1023   int result_size = 80;
1024
1025   if (prrompt)
1026     {
1027       /* Don't use a _filtered function here.  It causes the assumed
1028          character position to be off, since the newline we read from
1029          the user is not accounted for.  */
1030       fputs (prrompt, stdout);
1031       fflush (stdout);
1032     }
1033
1034   result = (char *) xmalloc (result_size);
1035
1036   while (1)
1037     {
1038       /* Read from stdin if we are executing a user defined command.
1039          This is the right thing for prompt_for_continue, at least.  */
1040       c = fgetc (instream ? instream : stdin);
1041
1042       if (c == EOF)
1043         {
1044           free (result);
1045           return NULL;
1046         }
1047
1048       if (c == '\n')
1049         break;
1050
1051       result[input_index++] = c;
1052       while (input_index >= result_size)
1053         {
1054           result_size *= 2;
1055           result = (char *) xrealloc (result, result_size);
1056         }
1057     }
1058
1059   result[input_index++] = '\0';
1060   return result;
1061 }
1062
1063 /* Variables which control command line editing and history
1064    substitution.  These variables are given default values at the end
1065    of this file.  */
1066 static int command_editing_p;
1067 static int history_expansion_p;
1068 static int write_history_p;
1069 static int history_size;
1070 static char *history_filename;
1071
1072 /* Variables which are necessary for fancy command line editing.  */
1073 char *gdb_completer_word_break_characters =
1074   " \t\n!@#$%^&*()+=|~`}{[]\"';:?/>.<,-";
1075
1076 /* When completing on command names, we remove '-' from the list of
1077    word break characters, since we use it in command names.  If the
1078    readline library sees one in any of the current completion strings,
1079    it thinks that the string needs to be quoted and automatically supplies
1080    a leading quote. */
1081 char *gdb_completer_command_word_break_characters =
1082   " \t\n!@#$%^&*()+=|~`}{[]\"';:?/>.<,";
1083
1084 /* Characters that can be used to quote completion strings.  Note that we
1085    can't include '"' because the gdb C parser treats such quoted sequences
1086    as strings. */
1087 char *gdb_completer_quote_characters =
1088   "'";
1089
1090 /* Functions that are used as part of the fancy command line editing.  */
1091
1092 /* This can be used for functions which don't want to complete on symbols
1093    but don't want to complete on anything else either.  */
1094 /* ARGSUSED */
1095 char **
1096 noop_completer (text)
1097      char *text;
1098 {
1099   return NULL;
1100 }
1101
1102 /* Generate symbol names one by one for the completer.  Each time we are
1103    called return another potential completion to the caller.
1104
1105    TEXT is what we expect the symbol to start with.
1106
1107    MATCHES is the number of matches that have currently been collected from
1108    calling this completion function.  When zero, then we need to initialize,
1109    otherwise the initialization has already taken place and we can just
1110    return the next potential completion string.
1111
1112    Returns NULL if there are no more completions, else a pointer to a string
1113    which is a possible completion.
1114
1115    RL_LINE_BUFFER is available to be looked at; it contains the entire text
1116    of the line.  RL_POINT is the offset in that line of the cursor.  You
1117    should pretend that the line ends at RL_POINT. */
1118
1119 static char *
1120 symbol_completion_function (text, matches)
1121      char *text;
1122      int matches;
1123 {
1124   static char **list = (char **)NULL;           /* Cache of completions */
1125   static int index;                             /* Next cached completion */
1126   char *output = NULL;
1127   char *tmp_command, *p;
1128   struct cmd_list_element *c, *result_list;
1129   extern char *rl_line_buffer;
1130   extern int rl_point;
1131
1132   if (matches == 0)
1133     {
1134       /* The caller is beginning to accumulate a new set of completions, so
1135          we need to find all of them now, and cache them for returning one at
1136          a time on future calls. */
1137
1138       if (list)
1139         {
1140           /* Free the storage used by LIST, but not by the strings inside.
1141              This is because rl_complete_internal () frees the strings. */
1142           free ((PTR)list);
1143         }
1144       list = 0;
1145       index = 0;
1146
1147       /* Choose the default set of word break characters to break completions.
1148          If we later find out that we are doing completions on command strings
1149          (as opposed to strings supplied by the individual command completer
1150          functions, which can be any string) then we will switch to the
1151          special word break set for command strings, which leaves out the
1152          '-' character used in some commands. */
1153
1154       rl_completer_word_break_characters =
1155           gdb_completer_word_break_characters;
1156
1157       /* Decide whether to complete on a list of gdb commands or on symbols. */
1158       tmp_command = (char *) alloca (rl_point + 1);
1159       p = tmp_command;
1160
1161       strncpy (tmp_command, rl_line_buffer, rl_point);
1162       tmp_command[rl_point] = '\0';
1163
1164       if (rl_point == 0)
1165         {
1166           /* An empty line we want to consider ambiguous; that is, it
1167              could be any command.  */
1168           c = (struct cmd_list_element *) -1;
1169           result_list = 0;
1170         }
1171       else
1172         {
1173           c = lookup_cmd_1 (&p, cmdlist, &result_list, 1);
1174         }
1175
1176       /* Move p up to the next interesting thing.  */
1177       while (*p == ' ' || *p == '\t')
1178         {
1179           p++;
1180         }
1181
1182       if (!c)
1183         {
1184           /* He's typed something unrecognizable.  Sigh.  */
1185           list = NULL;
1186         }
1187       else if (c == (struct cmd_list_element *) -1)
1188         {
1189           /* If we didn't recognize everything up to the thing that
1190              needs completing, and we don't know what command it is
1191              yet, we are in trouble. */
1192
1193           if (p + strlen(text) != tmp_command + rl_point)
1194             {
1195               /* This really should not produce an error.  Better would
1196                  be to pretend to hit RETURN here; this would produce a
1197                  response like "Ambiguous command: foo, foobar, etc",
1198                  and leave the line available for re-entry with ^P.
1199                  Instead, this error blows away the user's typed input
1200                  without any way to get it back.  */
1201               error ("  Unrecognized command.");
1202             }
1203
1204           /* He's typed something ambiguous.  This is easier.  */
1205           if (result_list)
1206             {
1207               list = complete_on_cmdlist (*result_list->prefixlist, text);
1208             }
1209           else
1210             {
1211               list = complete_on_cmdlist (cmdlist, text);
1212             }
1213           rl_completer_word_break_characters =
1214               gdb_completer_command_word_break_characters;
1215         }
1216       else
1217         {
1218           /* If we've gotten this far, gdb has recognized a full
1219              command.  There are several possibilities:
1220
1221              1) We need to complete on the command.
1222              2) We need to complete on the possibilities coming after
1223              the command.
1224              2) We need to complete the text of what comes after the
1225              command.   */
1226
1227           if (!*p && *text)
1228             {
1229               /* Always (might be longer versions of thie command).  */
1230               list = complete_on_cmdlist (result_list, text);
1231               rl_completer_word_break_characters =
1232                   gdb_completer_command_word_break_characters;
1233             }
1234           else if (!*p && !*text)
1235             {
1236               if (c->prefixlist)
1237                 {
1238                   list = complete_on_cmdlist (*c->prefixlist, "");
1239                   rl_completer_word_break_characters =
1240                       gdb_completer_command_word_break_characters;
1241                 }
1242               else
1243                 {
1244                   list = (*c->completer) ("");
1245                 }
1246             }
1247           else
1248             {
1249               if (c->prefixlist && !c->allow_unknown)
1250                 {
1251                   /* Something like "info adsfkdj".  But error() is not the
1252                      proper response; just return no completions instead. */
1253                   list = NULL;
1254                 }
1255               else
1256                 {
1257                   list = (*c->completer) (text);
1258                 }
1259             }
1260         }
1261     }
1262
1263   /* If we found a list of potential completions during initialization then
1264      dole them out one at a time.  The vector of completions is NULL
1265      terminated, so after returning the last one, return NULL (and continue
1266      to do so) each time we are called after that, until a new list is
1267      available. */
1268
1269   if (list)
1270     {
1271       output = list[index];
1272       if (output)
1273         {
1274           index++;
1275         }
1276     }
1277
1278   return (output);
1279 }
1280
1281 /* Skip over a possibly quoted word (as defined by the quote characters
1282    and word break characters the completer uses).  Returns pointer to the
1283    location after the "word". */
1284
1285 char *
1286 skip_quoted (str)
1287      char *str;
1288 {
1289   char quote_char = '\0';
1290   char *scan;
1291
1292   for (scan = str; *scan != '\0'; scan++)
1293     {
1294       if (quote_char != '\0')
1295         {
1296           /* Ignore everything until the matching close quote char */
1297           if (*scan == quote_char)
1298             {
1299               /* Found matching close quote. */
1300               scan++;
1301               break;
1302             }
1303         }
1304       else if (strchr (gdb_completer_quote_characters, *scan))
1305         {
1306           /* Found start of a quoted string. */
1307           quote_char = *scan;
1308         }
1309       else if (strchr (gdb_completer_word_break_characters, *scan))
1310         {
1311           break;
1312         }
1313     }
1314   return (scan);
1315 }
1316
1317 \f
1318 #ifdef STOP_SIGNAL
1319 static void
1320 stop_sig (signo)
1321 int signo;
1322 {
1323 #if STOP_SIGNAL == SIGTSTP
1324   signal (SIGTSTP, SIG_DFL);
1325   sigsetmask (0);
1326   kill (getpid (), SIGTSTP);
1327   signal (SIGTSTP, stop_sig);
1328 #else
1329   signal (STOP_SIGNAL, stop_sig);
1330 #endif
1331   printf ("%s", prompt);
1332   fflush (stdout);
1333
1334   /* Forget about any previous command -- null line now will do nothing.  */
1335   dont_repeat ();
1336 }
1337 #endif /* STOP_SIGNAL */
1338
1339 /* Initialize signal handlers. */
1340 static void
1341 do_nothing (signo)
1342 int signo;
1343 {
1344 }
1345
1346 static void
1347 init_signals ()
1348 {
1349   signal (SIGINT, request_quit);
1350
1351   /* If we initialize SIGQUIT to SIG_IGN, then the SIG_IGN will get
1352      passed to the inferior, which we don't want.  It would be
1353      possible to do a "signal (SIGQUIT, SIG_DFL)" after we fork, but
1354      on BSD4.3 systems using vfork, that can affect the
1355      GDB process as well as the inferior (the signal handling tables
1356      might be in memory, shared between the two).  Since we establish
1357      a handler for SIGQUIT, when we call exec it will set the signal
1358      to SIG_DFL for us.  */
1359   signal (SIGQUIT, do_nothing);
1360   if (signal (SIGHUP, do_nothing) != SIG_IGN)
1361     signal (SIGHUP, disconnect);
1362   signal (SIGFPE, float_handler);
1363
1364 #if defined(SIGWINCH) && defined(SIGWINCH_HANDLER)
1365   signal (SIGWINCH, SIGWINCH_HANDLER);
1366 #endif
1367 }
1368 \f
1369 /* Read one line from the command input stream `instream'
1370    into the local static buffer `linebuffer' (whose current length
1371    is `linelength').
1372    The buffer is made bigger as necessary.
1373    Returns the address of the start of the line.
1374
1375    NULL is returned for end of file.
1376
1377    *If* the instream == stdin & stdin is a terminal, the line read
1378    is copied into the file line saver (global var char *line,
1379    length linesize) so that it can be duplicated.
1380
1381    This routine either uses fancy command line editing or
1382    simple input as the user has requested.  */
1383
1384 char *
1385 command_line_input (prrompt, repeat)
1386      char *prrompt;
1387      int repeat;
1388 {
1389   static char *linebuffer = 0;
1390   static unsigned linelength = 0;
1391   register char *p;
1392   char *p1;
1393   char *rl;
1394   char *local_prompt = prrompt;
1395   register int c;
1396   char *nline;
1397   char got_eof = 0;
1398
1399   if (linebuffer == 0)
1400     {
1401       linelength = 80;
1402       linebuffer = (char *) xmalloc (linelength);
1403     }
1404
1405   p = linebuffer;
1406
1407   /* Control-C quits instantly if typed while in this loop
1408      since it should not wait until the user types a newline.  */
1409   immediate_quit++;
1410 #ifdef STOP_SIGNAL
1411   signal (STOP_SIGNAL, stop_sig);
1412 #endif
1413
1414   while (1)
1415     {
1416       /* Reports are that some Sys V's don't flush stdout/err on reads
1417          from stdin, when stdin/out are sockets rather than ttys.  So we
1418          have to do it ourselves, to make emacs-gdb and xxgdb work.
1419          On other machines, doing this once per input should be a cheap nop.  */
1420       fflush (stdout);
1421       fflush (stderr);
1422
1423       /* Don't use fancy stuff if not talking to stdin.  */
1424       if (command_editing_p && instream == stdin
1425           && ISATTY (instream))
1426         rl = readline (local_prompt);
1427       else
1428         rl = gdb_readline (local_prompt);
1429
1430       if (!rl || rl == (char *) EOF)
1431         {
1432           got_eof = 1;
1433           break;
1434         }
1435       if (strlen(rl) + 1 + (p - linebuffer) > linelength)
1436         {
1437           linelength = strlen(rl) + 1 + (p - linebuffer);
1438           nline = (char *) xrealloc (linebuffer, linelength);
1439           p += nline - linebuffer;
1440           linebuffer = nline;
1441         }
1442       p1 = rl;
1443       /* Copy line.  Don't copy null at end.  (Leaves line alone
1444          if this was just a newline)  */
1445       while (*p1)
1446         *p++ = *p1++;
1447
1448       free (rl);                        /* Allocated in readline.  */
1449
1450       if (p == linebuffer || *(p - 1) != '\\')
1451         break;
1452
1453       p--;                      /* Put on top of '\'.  */
1454       local_prompt = (char *) 0;
1455   }
1456
1457 #ifdef STOP_SIGNAL
1458   signal (STOP_SIGNAL, SIG_DFL);
1459 #endif
1460   immediate_quit--;
1461
1462   if (got_eof)
1463     return NULL;
1464
1465   /* Do history expansion if that is wished.  */
1466   if (history_expansion_p && instream == stdin
1467       && ISATTY (instream))
1468     {
1469       char *history_value;
1470       int expanded;
1471
1472       *p = '\0';                /* Insert null now.  */
1473       expanded = history_expand (linebuffer, &history_value);
1474       if (expanded)
1475         {
1476           /* Print the changes.  */
1477           printf ("%s\n", history_value);
1478
1479           /* If there was an error, call this function again.  */
1480           if (expanded < 0)
1481             {
1482               free (history_value);
1483               return command_line_input (prrompt, repeat);
1484             }
1485           if (strlen (history_value) > linelength)
1486             {
1487               linelength = strlen (history_value) + 1;
1488               linebuffer = (char *) xrealloc (linebuffer, linelength);
1489             }
1490           strcpy (linebuffer, history_value);
1491           p = linebuffer + strlen(linebuffer);
1492           free (history_value);
1493         }
1494     }
1495
1496   /* If we just got an empty line, and that is supposed
1497      to repeat the previous command, return the value in the
1498      global buffer.  */
1499   if (repeat)
1500     {
1501       if (p == linebuffer)
1502         return line;
1503       p1 = linebuffer;
1504       while (*p1 == ' ' || *p1 == '\t')
1505         p1++;
1506       if (!*p1)
1507         return line;
1508     }
1509
1510   *p = 0;
1511
1512   /* Add line to history if appropriate.  */
1513   if (instream == stdin
1514       && ISATTY (stdin) && *linebuffer)
1515     add_history (linebuffer);
1516
1517   /* Note: lines consisting soley of comments are added to the command
1518      history.  This is useful when you type a command, and then
1519      realize you don't want to execute it quite yet.  You can comment
1520      out the command and then later fetch it from the value history
1521      and remove the '#'.  The kill ring is probably better, but some
1522      people are in the habit of commenting things out.  */
1523   p1 = linebuffer;
1524   while ((c = *p1++) != '\0')
1525     {
1526       if (c == '"')
1527         while ((c = *p1++) != '"')
1528           {
1529             /* Make sure an escaped '"' doesn't make us think the string
1530                is ended.  */
1531             if (c == '\\')
1532               parse_escape (&p1);
1533             if (c == '\0')
1534               break;
1535           }
1536       else if (c == '\'')
1537         while ((c = *p1++) != '\'')
1538           {
1539             /* Make sure an escaped '\'' doesn't make us think the string
1540                is ended.  */
1541             if (c == '\\')
1542               parse_escape (&p1);
1543             if (c == '\0')
1544               break;
1545           }
1546       else if (c == '#')
1547         {
1548           /* Found a comment.  */
1549           p1[-1] = '\0';
1550           break;
1551         }
1552     }
1553
1554   /* Save into global buffer if appropriate.  */
1555   if (repeat)
1556     {
1557       if (linelength > linesize)
1558         {
1559           line = xrealloc (line, linelength);
1560           linesize = linelength;
1561         }
1562       strcpy (line, linebuffer);
1563       return line;
1564     }
1565
1566   return linebuffer;
1567 }
1568 \f
1569 /* Read lines from the input stream
1570    and accumulate them in a chain of struct command_line's
1571    which is then returned.  */
1572
1573 struct command_line *
1574 read_command_lines ()
1575 {
1576   struct command_line *first = 0;
1577   register struct command_line *next, *tail = 0;
1578   register char *p, *p1;
1579   struct cleanup *old_chain = 0;
1580
1581   while (1)
1582     {
1583       dont_repeat ();
1584       p = command_line_input ((char *) NULL, instream == stdin);
1585       if (p == NULL)
1586         /* Treat end of file like "end".  */
1587         break;
1588
1589       /* Remove leading and trailing blanks.  */
1590       while (*p == ' ' || *p == '\t') p++;
1591       p1 = p + strlen (p);
1592       while (p1 != p && (p1[-1] == ' ' || p1[-1] == '\t')) p1--;
1593
1594       /* Is this "end"?  */
1595       if (p1 - p == 3 && !strncmp (p, "end", 3))
1596         break;
1597
1598       /* No => add this line to the chain of command lines.  */
1599       next = (struct command_line *) xmalloc (sizeof (struct command_line));
1600       next->line = savestring (p, p1 - p);
1601       next->next = 0;
1602       if (tail)
1603         {
1604           tail->next = next;
1605         }
1606       else
1607         {
1608           /* We just read the first line.
1609              From now on, arrange to throw away the lines we have
1610              if we quit or get an error while inside this function.  */
1611           first = next;
1612           old_chain = make_cleanup (free_command_lines, &first);
1613         }
1614       tail = next;
1615     }
1616
1617   dont_repeat ();
1618
1619   /* Now we are about to return the chain to our caller,
1620      so freeing it becomes his responsibility.  */
1621   if (first)
1622     discard_cleanups (old_chain);
1623   return first;
1624 }
1625
1626 /* Free a chain of struct command_line's.  */
1627
1628 void
1629 free_command_lines (lptr)
1630       struct command_line **lptr;
1631 {
1632   register struct command_line *l = *lptr;
1633   register struct command_line *next;
1634
1635   while (l)
1636     {
1637       next = l->next;
1638       free (l->line);
1639       free ((PTR)l);
1640       l = next;
1641     }
1642 }
1643 \f
1644 /* Add an element to the list of info subcommands.  */
1645
1646 void
1647 add_info (name, fun, doc)
1648      char *name;
1649      void (*fun) PARAMS ((char *, int));
1650      char *doc;
1651 {
1652   add_cmd (name, no_class, fun, doc, &infolist);
1653 }
1654
1655 /* Add an alias to the list of info subcommands.  */
1656
1657 void
1658 add_info_alias (name, oldname, abbrev_flag)
1659      char *name;
1660      char *oldname;
1661      int abbrev_flag;
1662 {
1663   add_alias_cmd (name, oldname, 0, abbrev_flag, &infolist);
1664 }
1665
1666 /* The "info" command is defined as a prefix, with allow_unknown = 0.
1667    Therefore, its own definition is called only for "info" with no args.  */
1668
1669 /* ARGSUSED */
1670 static void
1671 info_command (arg, from_tty)
1672      char *arg;
1673      int from_tty;
1674 {
1675   printf ("\"info\" must be followed by the name of an info command.\n");
1676   help_list (infolist, "info ", -1, stdout);
1677 }
1678
1679 /* The "show" command with no arguments shows all the settings.  */
1680
1681 /* ARGSUSED */
1682 static void
1683 show_command (arg, from_tty)
1684      char *arg;
1685      int from_tty;
1686 {
1687   cmd_show_list (showlist, from_tty, "");
1688 }
1689 \f
1690 /* Add an element to the list of commands.  */
1691
1692 void
1693 add_com (name, class, fun, doc)
1694      char *name;
1695      enum command_class class;
1696      void (*fun) PARAMS ((char *, int));
1697      char *doc;
1698 {
1699   add_cmd (name, class, fun, doc, &cmdlist);
1700 }
1701
1702 /* Add an alias or abbreviation command to the list of commands.  */
1703
1704 void
1705 add_com_alias (name, oldname, class, abbrev_flag)
1706      char *name;
1707      char *oldname;
1708      enum command_class class;
1709      int abbrev_flag;
1710 {
1711   add_alias_cmd (name, oldname, class, abbrev_flag, &cmdlist);
1712 }
1713
1714 void
1715 error_no_arg (why)
1716      char *why;
1717 {
1718   error ("Argument required (%s).", why);
1719 }
1720
1721 /* ARGSUSED */
1722 static void
1723 help_command (command, from_tty)
1724      char *command;
1725      int from_tty; /* Ignored */
1726 {
1727   help_cmd (command, stdout);
1728 }
1729 \f
1730 static void
1731 validate_comname (comname)
1732      char *comname;
1733 {
1734   register char *p;
1735
1736   if (comname == 0)
1737     error_no_arg ("name of command to define");
1738
1739   p = comname;
1740   while (*p)
1741     {
1742       if (!isalnum(*p) && *p != '-')
1743         error ("Junk in argument list: \"%s\"", p);
1744       p++;
1745     }
1746 }
1747
1748 /* This is just a placeholder in the command data structures.  */
1749 static void
1750 user_defined_command (ignore, from_tty)
1751      char *ignore;
1752      int from_tty;
1753 {
1754 }
1755
1756 static void
1757 define_command (comname, from_tty)
1758      char *comname;
1759      int from_tty;
1760 {
1761   register struct command_line *cmds;
1762   register struct cmd_list_element *c, *newc, *hookc = 0;
1763   char *tem = comname;
1764 #define HOOK_STRING     "hook-"
1765 #define HOOK_LEN 5
1766
1767   validate_comname (comname);
1768
1769   /* Look it up, and verify that we got an exact match.  */
1770   c = lookup_cmd (&tem, cmdlist, "", -1, 1);
1771   if (c && !STREQ (comname, c->name))
1772     c = 0;
1773
1774   if (c)
1775     {
1776       if (c->class == class_user || c->class == class_alias)
1777         tem = "Redefine command \"%s\"? ";
1778       else
1779         tem = "Really redefine built-in command \"%s\"? ";
1780       if (!query (tem, c->name))
1781         error ("Command \"%s\" not redefined.", c->name);
1782     }
1783
1784   /* If this new command is a hook, then mark the command which it
1785      is hooking.  Note that we allow hooking `help' commands, so that
1786      we can hook the `stop' pseudo-command.  */
1787
1788   if (!strncmp (comname, HOOK_STRING, HOOK_LEN))
1789     {
1790       /* Look up cmd it hooks, and verify that we got an exact match.  */
1791       tem = comname+HOOK_LEN;
1792       hookc = lookup_cmd (&tem, cmdlist, "", -1, 0);
1793       if (hookc && !STREQ (comname+HOOK_LEN, hookc->name))
1794         hookc = 0;
1795       if (!hookc)
1796         {
1797           warning ("Your new `%s' command does not hook any existing command.",
1798                    comname);
1799           if (!query ("Proceed? ", (char *)0))
1800             error ("Not confirmed.");
1801         }
1802     }
1803
1804   comname = savestring (comname, strlen (comname));
1805
1806   /* If the rest of the commands will be case insensitive, this one
1807      should behave in the same manner. */
1808   for (tem = comname; *tem; tem++)
1809     if (isupper(*tem)) *tem = tolower(*tem);
1810
1811   if (from_tty)
1812     {
1813       printf ("Type commands for definition of \"%s\".\n\
1814 End with a line saying just \"end\".\n", comname);
1815       fflush (stdout);
1816     }
1817
1818   cmds = read_command_lines ();
1819
1820   if (c && c->class == class_user)
1821     free_command_lines (&c->user_commands);
1822
1823   newc = add_cmd (comname, class_user, user_defined_command,
1824            (c && c->class == class_user)
1825            ? c->doc : savestring ("User-defined.", 13), &cmdlist);
1826   newc->user_commands = cmds;
1827
1828   /* If this new command is a hook, then mark both commands as being
1829      tied.  */
1830   if (hookc)
1831     {
1832       hookc->hook = newc;       /* Target gets hooked.  */
1833       newc->hookee = hookc;     /* We are marked as hooking target cmd.  */
1834     }
1835 }
1836
1837 static void
1838 document_command (comname, from_tty)
1839      char *comname;
1840      int from_tty;
1841 {
1842   struct command_line *doclines;
1843   register struct cmd_list_element *c;
1844   char *tem = comname;
1845
1846   validate_comname (comname);
1847
1848   c = lookup_cmd (&tem, cmdlist, "", 0, 1);
1849
1850   if (c->class != class_user)
1851     error ("Command \"%s\" is built-in.", comname);
1852
1853   if (from_tty)
1854     printf ("Type documentation for \"%s\".\n\
1855 End with a line saying just \"end\".\n", comname);
1856
1857   doclines = read_command_lines ();
1858
1859   if (c->doc) free (c->doc);
1860
1861   {
1862     register struct command_line *cl1;
1863     register int len = 0;
1864
1865     for (cl1 = doclines; cl1; cl1 = cl1->next)
1866       len += strlen (cl1->line) + 1;
1867
1868     c->doc = (char *) xmalloc (len + 1);
1869     *c->doc = 0;
1870
1871     for (cl1 = doclines; cl1; cl1 = cl1->next)
1872       {
1873         strcat (c->doc, cl1->line);
1874         if (cl1->next)
1875           strcat (c->doc, "\n");
1876       }
1877   }
1878
1879   free_command_lines (&doclines);
1880 }
1881 \f
1882 static void
1883 print_gnu_advertisement()
1884 {
1885     printf ("\
1886 GDB is free software and you are welcome to distribute copies of it\n\
1887  under certain conditions; type \"show copying\" to see the conditions.\n\
1888 There is absolutely no warranty for GDB; type \"show warranty\" for details.\n\
1889 ");
1890 }
1891
1892 static void
1893 print_gdb_version (stream)
1894   FILE *stream;
1895 {
1896   fprintf_filtered (stream, "\
1897 GDB %s, Copyright 1993 Free Software Foundation, Inc.",
1898           version);
1899 }
1900
1901 /* ARGSUSED */
1902 static void
1903 show_version (args, from_tty)
1904      char *args;
1905      int from_tty;
1906 {
1907   immediate_quit++;
1908   print_gnu_advertisement ();
1909   print_gdb_version (stdout);
1910   printf_filtered ("\n");
1911   immediate_quit--;
1912 }
1913 \f
1914 /* xgdb calls this to reprint the usual GDB prompt.  */
1915
1916 void
1917 print_prompt ()
1918 {
1919   printf ("%s", prompt);
1920   fflush (stdout);
1921 }
1922 \f
1923 static void
1924 quit_command (args, from_tty)
1925      char *args;
1926      int from_tty;
1927 {
1928   if (inferior_pid != 0 && target_has_execution)
1929     {
1930       if (attach_flag)
1931         {
1932           if (query ("The program is running.  Quit anyway (and detach it)? "))
1933             target_detach (args, from_tty);
1934           else
1935             error ("Not confirmed.");
1936         }
1937       else
1938         {
1939           if (query ("The program is running.  Quit anyway (and kill it)? "))
1940             target_kill ();
1941           else
1942             error ("Not confirmed.");
1943         }
1944     }
1945   /* Save the history information if it is appropriate to do so.  */
1946   if (write_history_p && history_filename)
1947     write_history (history_filename);
1948   exit (0);
1949 }
1950
1951 /* Returns whether GDB is running on a terminal and whether the user
1952    desires that questions be asked of them on that terminal.  */
1953
1954 int
1955 input_from_terminal_p ()
1956 {
1957   return gdb_has_a_terminal && (instream == stdin) & caution;
1958 }
1959 \f
1960 /* ARGSUSED */
1961 static void
1962 pwd_command (args, from_tty)
1963      char *args;
1964      int from_tty;
1965 {
1966   if (args) error ("The \"pwd\" command does not take an argument: %s", args);
1967   getcwd (dirbuf, sizeof (dirbuf));
1968
1969   if (!STREQ (dirbuf, current_directory))
1970     printf ("Working directory %s\n (canonically %s).\n",
1971             current_directory, dirbuf);
1972   else
1973     printf ("Working directory %s.\n", current_directory);
1974 }
1975
1976 static void
1977 cd_command (dir, from_tty)
1978      char *dir;
1979      int from_tty;
1980 {
1981   int len;
1982   int change;
1983
1984   /* If the new directory is absolute, repeat is a no-op; if relative,
1985      repeat might be useful but is more likely to be a mistake.  */
1986   dont_repeat ();
1987
1988   if (dir == 0)
1989     error_no_arg ("new working directory");
1990
1991   dir = tilde_expand (dir);
1992   make_cleanup (free, dir);
1993
1994   if (chdir (dir) < 0)
1995     perror_with_name (dir);
1996
1997   len = strlen (dir);
1998   dir = savestring (dir, len - (len > 1 && dir[len-1] == '/'));
1999   if (dir[0] == '/')
2000     current_directory = dir;
2001   else
2002     {
2003       current_directory = concat (current_directory, "/", dir, NULL);
2004       free (dir);
2005     }
2006
2007   /* Now simplify any occurrences of `.' and `..' in the pathname.  */
2008
2009   change = 1;
2010   while (change)
2011     {
2012       char *p;
2013       change = 0;
2014
2015       for (p = current_directory; *p;)
2016         {
2017           if (!strncmp (p, "/./", 2)
2018               && (p[2] == 0 || p[2] == '/'))
2019             strcpy (p, p + 2);
2020           else if (!strncmp (p, "/..", 3)
2021                    && (p[3] == 0 || p[3] == '/')
2022                    && p != current_directory)
2023             {
2024               char *q = p;
2025               while (q != current_directory && q[-1] != '/') q--;
2026               if (q != current_directory)
2027                 {
2028                   strcpy (q-1, p+3);
2029                   p = q-1;
2030                 }
2031             }
2032           else p++;
2033         }
2034     }
2035
2036   forget_cached_source_info ();
2037
2038   if (from_tty)
2039     pwd_command ((char *) 0, 1);
2040 }
2041 \f
2042 /* ARGSUSED */
2043 static void
2044 source_command (args, from_tty)
2045      char *args;
2046      int from_tty;
2047 {
2048   FILE *stream;
2049   struct cleanup *cleanups;
2050   char *file = args;
2051
2052   if (file == NULL)
2053     {
2054       error ("source command requires pathname of file to source.");
2055     }
2056
2057   file = tilde_expand (file);
2058   make_cleanup (free, file);
2059
2060   stream = fopen (file, FOPEN_RT);
2061   if (stream == 0)
2062     perror_with_name (file);
2063
2064   cleanups = make_cleanup (fclose, stream);
2065
2066   read_command_file (stream);
2067
2068   do_cleanups (cleanups);
2069 }
2070
2071 /* ARGSUSED */
2072 static void
2073 echo_command (text, from_tty)
2074      char *text;
2075      int from_tty;
2076 {
2077   char *p = text;
2078   register int c;
2079
2080   if (text)
2081     while ((c = *p++) != '\0')
2082       {
2083         if (c == '\\')
2084           {
2085             /* \ at end of argument is used after spaces
2086                so they won't be lost.  */
2087             if (*p == 0)
2088               return;
2089
2090             c = parse_escape (&p);
2091             if (c >= 0)
2092               printf_filtered ("%c", c);
2093           }
2094         else
2095           printf_filtered ("%c", c);
2096       }
2097
2098   /* Force this output to appear now.  */
2099   wrap_here ("");
2100   fflush (stdout);
2101 }
2102
2103 \f
2104 /* Functions to manipulate command line editing control variables.  */
2105
2106 /* Number of commands to print in each call to show_commands.  */
2107 #define Hist_print 10
2108 static void
2109 show_commands (args, from_tty)
2110      char *args;
2111      int from_tty;
2112 {
2113   /* Index for history commands.  Relative to history_base.  */
2114   int offset;
2115
2116   /* Number of the history entry which we are planning to display next.
2117      Relative to history_base.  */
2118   static int num = 0;
2119
2120   /* The first command in the history which doesn't exist (i.e. one more
2121      than the number of the last command).  Relative to history_base.  */
2122   int hist_len;
2123
2124   extern struct _hist_entry *history_get PARAMS ((int));
2125   extern int history_base;
2126
2127   /* Print out some of the commands from the command history.  */
2128   /* First determine the length of the history list.  */
2129   hist_len = history_size;
2130   for (offset = 0; offset < history_size; offset++)
2131     {
2132       if (!history_get (history_base + offset))
2133         {
2134           hist_len = offset;
2135           break;
2136         }
2137     }
2138
2139   if (args)
2140     {
2141       if (args[0] == '+' && args[1] == '\0')
2142         /* "info editing +" should print from the stored position.  */
2143         ;
2144       else
2145         /* "info editing <exp>" should print around command number <exp>.  */
2146         num = (parse_and_eval_address (args) - history_base) - Hist_print / 2;
2147     }
2148   /* "show commands" means print the last Hist_print commands.  */
2149   else
2150     {
2151       num = hist_len - Hist_print;
2152     }
2153
2154   if (num < 0)
2155     num = 0;
2156
2157   /* If there are at least Hist_print commands, we want to display the last
2158      Hist_print rather than, say, the last 6.  */
2159   if (hist_len - num < Hist_print)
2160     {
2161       num = hist_len - Hist_print;
2162       if (num < 0)
2163         num = 0;
2164     }
2165
2166   for (offset = num; offset < num + Hist_print && offset < hist_len; offset++)
2167     {
2168       printf_filtered ("%5d  %s\n", history_base + offset,
2169               (history_get (history_base + offset))->line);
2170     }
2171
2172   /* The next command we want to display is the next one that we haven't
2173      displayed yet.  */
2174   num += Hist_print;
2175
2176   /* If the user repeats this command with return, it should do what
2177      "show commands +" does.  This is unnecessary if arg is null,
2178      because "show commands +" is not useful after "show commands".  */
2179   if (from_tty && args)
2180     {
2181       args[0] = '+';
2182       args[1] = '\0';
2183     }
2184 }
2185
2186 /* Called by do_setshow_command.  */
2187 /* ARGSUSED */
2188 static void
2189 set_history_size_command (args, from_tty, c)
2190      char *args;
2191      int from_tty;
2192      struct cmd_list_element *c;
2193 {
2194   if (history_size == INT_MAX)
2195     unstifle_history ();
2196   else if (history_size >= 0)
2197     stifle_history (history_size);
2198   else
2199     {
2200       history_size = INT_MAX;
2201       error ("History size must be non-negative");
2202     }
2203 }
2204
2205 /* ARGSUSED */
2206 static void
2207 set_history (args, from_tty)
2208      char *args;
2209      int from_tty;
2210 {
2211   printf ("\"set history\" must be followed by the name of a history subcommand.\n");
2212   help_list (sethistlist, "set history ", -1, stdout);
2213 }
2214
2215 /* ARGSUSED */
2216 static void
2217 show_history (args, from_tty)
2218      char *args;
2219      int from_tty;
2220 {
2221   cmd_show_list (showhistlist, from_tty, "");
2222 }
2223
2224 int info_verbose = 0;           /* Default verbose msgs off */
2225
2226 /* Called by do_setshow_command.  An elaborate joke.  */
2227 /* ARGSUSED */
2228 static void
2229 set_verbose (args, from_tty, c)
2230      char *args;
2231      int from_tty;
2232      struct cmd_list_element *c;
2233 {
2234   char *cmdname = "verbose";
2235   struct cmd_list_element *showcmd;
2236
2237   showcmd = lookup_cmd_1 (&cmdname, showlist, NULL, 1);
2238
2239   if (info_verbose)
2240     {
2241       c->doc = "Set verbose printing of informational messages.";
2242       showcmd->doc = "Show verbose printing of informational messages.";
2243     }
2244   else
2245     {
2246       c->doc = "Set verbosity.";
2247       showcmd->doc = "Show verbosity.";
2248     }
2249 }
2250
2251 static void
2252 float_handler (signo)
2253 int signo;
2254 {
2255   /* This message is based on ANSI C, section 4.7.  Note that integer
2256      divide by zero causes this, so "float" is a misnomer.  */
2257   signal (SIGFPE, float_handler);
2258   error ("Erroneous arithmetic operation.");
2259 }
2260
2261 /* Return whether we are running a batch file or from terminal.  */
2262 int
2263 batch_mode ()
2264 {
2265   return !(instream == stdin && ISATTY (stdin));
2266 }
2267
2268 \f
2269 static void
2270 initialize_cmd_lists ()
2271 {
2272   cmdlist = NULL;
2273   infolist = NULL;
2274   enablelist = NULL;
2275   disablelist = NULL;
2276   deletelist = NULL;
2277   enablebreaklist = NULL;
2278   setlist = NULL;
2279   unsetlist = NULL;
2280   showlist = NULL;
2281   sethistlist = NULL;
2282   showhistlist = NULL;
2283   unsethistlist = NULL;
2284 #if MAINTENANCE_CMDS
2285   maintenancelist = NULL;
2286   maintenanceinfolist = NULL;
2287   maintenanceprintlist = NULL;
2288 #endif
2289   setprintlist = NULL;
2290   showprintlist = NULL;
2291   setchecklist = NULL;
2292   showchecklist = NULL;
2293 }
2294
2295 /* Init the history buffer.  Note that we are called after the init file(s)
2296  * have been read so that the user can change the history file via his
2297  * .gdbinit file (for instance).  The GDBHISTFILE environment variable
2298  * overrides all of this.
2299  */
2300
2301 static void
2302 initialize_history()
2303 {
2304   char *tmpenv;
2305
2306   tmpenv = getenv ("HISTSIZE");
2307   if (tmpenv)
2308     history_size = atoi (tmpenv);
2309   else if (!history_size)
2310     history_size = 256;
2311
2312   stifle_history (history_size);
2313
2314   tmpenv = getenv ("GDBHISTFILE");
2315   if (tmpenv)
2316     history_filename = savestring (tmpenv, strlen(tmpenv));
2317   else if (!history_filename) {
2318     /* We include the current directory so that if the user changes
2319        directories the file written will be the same as the one
2320        that was read.  */
2321     history_filename = concat (current_directory, "/.gdb_history", NULL);
2322   }
2323   read_history (history_filename);
2324 }
2325
2326 static void
2327 initialize_main ()
2328 {
2329   struct cmd_list_element *c;
2330
2331 #ifdef DEFAULT_PROMPT
2332   prompt = savestring (DEFAULT_PROMPT, strlen(DEFAULT_PROMPT));
2333 #else
2334   prompt = savestring ("(gdb) ", 6);
2335 #endif
2336
2337   /* Set the important stuff up for command editing.  */
2338   command_editing_p = 1;
2339   history_expansion_p = 0;
2340   write_history_p = 0;
2341
2342   /* Setup important stuff for command line editing.  */
2343   rl_completion_entry_function = (int (*)()) symbol_completion_function;
2344   rl_completer_word_break_characters = gdb_completer_word_break_characters;
2345   rl_completer_quote_characters = gdb_completer_quote_characters;
2346   rl_readline_name = "gdb";
2347
2348   /* Define the classes of commands.
2349      They will appear in the help list in the reverse of this order.  */
2350
2351   add_cmd ("internals", class_maintenance, NO_FUNCTION,
2352            "Maintenance commands.\n\
2353 Some gdb commands are provided just for use by gdb maintainers.\n\
2354 These commands are subject to frequent change, and may not be as\n\
2355 well documented as user commands.",
2356            &cmdlist);
2357   add_cmd ("obscure", class_obscure, NO_FUNCTION, "Obscure features.", &cmdlist);
2358   add_cmd ("aliases", class_alias, NO_FUNCTION, "Aliases of other commands.", &cmdlist);
2359   add_cmd ("user-defined", class_user, NO_FUNCTION, "User-defined commands.\n\
2360 The commands in this class are those defined by the user.\n\
2361 Use the \"define\" command to define a command.", &cmdlist);
2362   add_cmd ("support", class_support, NO_FUNCTION, "Support facilities.", &cmdlist);
2363   add_cmd ("status", class_info, NO_FUNCTION, "Status inquiries.", &cmdlist);
2364   add_cmd ("files", class_files, NO_FUNCTION, "Specifying and examining files.", &cmdlist);
2365   add_cmd ("breakpoints", class_breakpoint, NO_FUNCTION, "Making program stop at certain points.", &cmdlist);
2366   add_cmd ("data", class_vars, NO_FUNCTION, "Examining data.", &cmdlist);
2367   add_cmd ("stack", class_stack, NO_FUNCTION, "Examining the stack.\n\
2368 The stack is made up of stack frames.  Gdb assigns numbers to stack frames\n\
2369 counting from zero for the innermost (currently executing) frame.\n\n\
2370 At any time gdb identifies one frame as the \"selected\" frame.\n\
2371 Variable lookups are done with respect to the selected frame.\n\
2372 When the program being debugged stops, gdb selects the innermost frame.\n\
2373 The commands below can be used to select other frames by number or address.",
2374            &cmdlist);
2375   add_cmd ("running", class_run, NO_FUNCTION, "Running the program.", &cmdlist);
2376
2377   add_com ("pwd", class_files, pwd_command,
2378            "Print working directory.  This is used for your program as well.");
2379   add_com ("cd", class_files, cd_command,
2380            "Set working directory to DIR for debugger and program being debugged.\n\
2381 The change does not take effect for the program being debugged\n\
2382 until the next time it is started.");
2383
2384   add_show_from_set
2385     (add_set_cmd ("prompt", class_support, var_string, (char *)&prompt,
2386            "Set gdb's prompt",
2387            &setlist),
2388      &showlist);
2389
2390   add_com ("echo", class_support, echo_command,
2391            "Print a constant string.  Give string as argument.\n\
2392 C escape sequences may be used in the argument.\n\
2393 No newline is added at the end of the argument;\n\
2394 use \"\\n\" if you want a newline to be printed.\n\
2395 Since leading and trailing whitespace are ignored in command arguments,\n\
2396 if you want to print some you must use \"\\\" before leading whitespace\n\
2397 to be printed or after trailing whitespace.");
2398   add_com ("document", class_support, document_command,
2399            "Document a user-defined command.\n\
2400 Give command name as argument.  Give documentation on following lines.\n\
2401 End with a line of just \"end\".");
2402   add_com ("define", class_support, define_command,
2403            "Define a new command name.  Command name is argument.\n\
2404 Definition appears on following lines, one command per line.\n\
2405 End with a line of just \"end\".\n\
2406 Use the \"document\" command to give documentation for the new command.\n\
2407 Commands defined in this way do not take arguments.");
2408
2409 #ifdef __STDC__
2410   add_com ("source", class_support, source_command,
2411            "Read commands from a file named FILE.\n\
2412 Note that the file \"" GDBINIT_FILENAME "\" is read automatically in this way\n\
2413 when gdb is started.");
2414 #else
2415   /* Punt file name, we can't help it easily.  */
2416   add_com ("source", class_support, source_command,
2417            "Read commands from a file named FILE.\n\
2418 Note that the file \".gdbinit\" is read automatically in this way\n\
2419 when gdb is started.");
2420 #endif
2421
2422   add_com ("quit", class_support, quit_command, "Exit gdb.");
2423   add_com ("help", class_support, help_command, "Print list of commands.");
2424   add_com_alias ("q", "quit", class_support, 1);
2425   add_com_alias ("h", "help", class_support, 1);
2426
2427
2428   c = add_set_cmd ("verbose", class_support, var_boolean, (char *)&info_verbose,
2429                    "Set ",
2430                    &setlist),
2431   add_show_from_set (c, &showlist);
2432   c->function.sfunc = set_verbose;
2433   set_verbose (NULL, 0, c);
2434
2435   add_show_from_set
2436     (add_set_cmd ("editing", class_support, var_boolean, (char *)&command_editing_p,
2437            "Set editing of command lines as they are typed.\n\
2438 Use \"on\" to enable to enable the editing, and \"off\" to disable it.\n\
2439 Without an argument, command line editing is enabled.  To edit, use\n\
2440 EMACS-like or VI-like commands like control-P or ESC.", &setlist),
2441      &showlist);
2442
2443   add_prefix_cmd ("history", class_support, set_history,
2444                   "Generic command for setting command history parameters.",
2445                   &sethistlist, "set history ", 0, &setlist);
2446   add_prefix_cmd ("history", class_support, show_history,
2447                   "Generic command for showing command history parameters.",
2448                   &showhistlist, "show history ", 0, &showlist);
2449
2450   add_show_from_set
2451     (add_set_cmd ("expansion", no_class, var_boolean, (char *)&history_expansion_p,
2452            "Set history expansion on command input.\n\
2453 Without an argument, history expansion is enabled.", &sethistlist),
2454      &showhistlist);
2455
2456   add_show_from_set
2457     (add_set_cmd ("save", no_class, var_boolean, (char *)&write_history_p,
2458            "Set saving of the history record on exit.\n\
2459 Use \"on\" to enable to enable the saving, and \"off\" to disable it.\n\
2460 Without an argument, saving is enabled.", &sethistlist),
2461      &showhistlist);
2462
2463   c = add_set_cmd ("size", no_class, var_integer, (char *)&history_size,
2464                    "Set the size of the command history, \n\
2465 ie. the number of previous commands to keep a record of.", &sethistlist);
2466   add_show_from_set (c, &showhistlist);
2467   c->function.sfunc = set_history_size_command;
2468
2469   add_show_from_set
2470     (add_set_cmd ("filename", no_class, var_filename, (char *)&history_filename,
2471            "Set the filename in which to record the command history\n\
2472  (the list of previous commands of which a record is kept).", &sethistlist),
2473      &showhistlist);
2474
2475   add_show_from_set
2476     (add_set_cmd ("confirm", class_support, var_boolean,
2477                   (char *)&caution,
2478                   "Set whether to confirm potentially dangerous operations.",
2479                   &setlist),
2480      &showlist);
2481
2482   add_prefix_cmd ("info", class_info, info_command,
2483         "Generic command for showing things about the program being debugged.",
2484                   &infolist, "info ", 0, &cmdlist);
2485   add_com_alias ("i", "info", class_info, 1);
2486
2487   add_prefix_cmd ("show", class_info, show_command,
2488                   "Generic command for showing things about the debugger.",
2489                   &showlist, "show ", 0, &cmdlist);
2490   /* Another way to get at the same thing.  */
2491   add_info ("set", show_command, "Show all GDB settings.");
2492
2493   add_cmd ("commands", no_class, show_commands,
2494            "Show the the history of commands you typed.\n\
2495 You can supply a command number to start with, or a `+' to start after\n\
2496 the previous command number shown.",
2497            &showlist);
2498
2499   add_cmd ("version", no_class, show_version,
2500            "Show what version of GDB this is.", &showlist);
2501 }