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 ((void));
  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 char gdbinit[] = GDBINIT_FILENAME;
 173
 174 #define ALL_CLEANUPS    ((struct cleanup *)0)
 175
 176 /* Version number of GDB, as a string.  */
 177
 178 extern char *version;
 179
 180 /* Message to be printed before the error message, when an error occurs.  */
 181
 182 extern char *error_pre_print;
 183
 184 /* Message to be printed before the warning message, when a warning occurs.  */
 185
 186 extern char *warning_pre_print;
 187
 188 extern char lang_frame_mismatch_warn[];         /* language.c */
 189
 190 /* Whether GDB's stdin is on a terminal.  */
 191
 192 extern int gdb_has_a_terminal;                  /* inflow.c */
 193
 194 /* Flag for whether we want all the "from_tty" gubbish printed.  */
 195
 196 int caution = 1;                        /* Default is yes, sigh. */
 197
 198 /*
 199  * Define all cmd_list_element's
 200  */
 201
 202 /* Chain containing all defined commands.  */
 203
 204 struct cmd_list_element *cmdlist;
 205
 206 /* Chain containing all defined info subcommands.  */
 207
 208 struct cmd_list_element *infolist;
 209
 210 /* Chain containing all defined enable subcommands. */
 211
 212 struct cmd_list_element *enablelist;
 213
 214 /* Chain containing all defined disable subcommands. */
 215
 216 struct cmd_list_element *disablelist;
 217
 218 /* Chain containing all defined delete subcommands. */
 219
 220 struct cmd_list_element *deletelist;
 221
 222 /* Chain containing all defined "enable breakpoint" subcommands. */
 223
 224 struct cmd_list_element *enablebreaklist;
 225
 226 /* Chain containing all defined set subcommands */
 227
 228 struct cmd_list_element *setlist;
 229
 230 /* Chain containing all defined unset subcommands */
 231
 232 struct cmd_list_element *unsetlist;
 233
 234 /* Chain containing all defined show subcommands.  */
 235
 236 struct cmd_list_element *showlist;
 237
 238 /* Chain containing all defined \"set history\".  */
 239
 240 struct cmd_list_element *sethistlist;
 241
 242 /* Chain containing all defined \"show history\".  */
 243
 244 struct cmd_list_element *showhistlist;
 245
 246 /* Chain containing all defined \"unset history\".  */
 247
 248 struct cmd_list_element *unsethistlist;
 249
 250 /* Chain containing all defined maintenance subcommands. */
 251
 252 #if MAINTENANCE_CMDS
 253 struct cmd_list_element *maintenancelist;
 254 #endif
 255
 256 /* Chain containing all defined "maintenance info" subcommands. */
 257
 258 #if MAINTENANCE_CMDS
 259 struct cmd_list_element *maintenanceinfolist;
 260 #endif
 261
 262 /* Chain containing all defined "maintenance print" subcommands. */
 263
 264 #if MAINTENANCE_CMDS
 265 struct cmd_list_element *maintenanceprintlist;
 266 #endif
 267
 268 struct cmd_list_element *setprintlist;
 269
 270 struct cmd_list_element *showprintlist;
 271
 272 struct cmd_list_element *setchecklist;
 273
 274 struct cmd_list_element *showchecklist;
 275
 276 /* stdio stream that command input is being read from.  */
 277
 278 FILE *instream;
 279
 280 /* Current working directory.  */
 281
 282 char *current_directory;
 283
 284 /* The directory name is actually stored here (usually).  */
 285 static char dirbuf[1024];
 286
 287 /* Function to call before reading a command, if nonzero.
 288    The function receives two args: an input stream,
 289    and a prompt string.  */
 290
 291 void (*window_hook) PARAMS ((FILE *, char *));
 292
 293 extern int frame_file_full_name;
 294 extern int mapped_symbol_files;
 295 extern int readnow_symbol_files;
 296
 297 int epoch_interface;
 298 int xgdb_verbose;
 299
 300 /* gdb prints this when reading a command interactively */
 301 static char *prompt;
 302
 303 /* Buffer used for reading command lines, and the size
 304    allocated for it so far.  */
 305
 306 char *line;
 307 int linesize = 100;
 308
 309 /* Baud rate specified for talking to serial target systems.  Default
 310    is left as a zero pointer, so targets can choose their own defaults.  */
 311
 312 char *baud_rate;
 313
 314 /* Signal to catch ^Z typed while reading a command: SIGTSTP or SIGCONT.  */
 315
 316 #ifndef STOP_SIGNAL
 317 #ifdef SIGTSTP
 318 #define STOP_SIGNAL SIGTSTP
 319 static void stop_sig PARAMS ((int));
 320 #endif
 321 #endif
 322
 323 /* Some System V have job control but not sigsetmask(). */
 324 #if !defined (HAVE_SIGSETMASK)
 325 #define HAVE_SIGSETMASK !defined (USG)
 326 #endif
 327
 328 #if 0 == (HAVE_SIGSETMASK)
 329 #define sigsetmask(n)
 330 #endif
 331 \f
 332 /* This is how `error' returns to command level.  */
 333
 334 jmp_buf to_top_level;
 335
 336 NORETURN void
 337 return_to_top_level ()
 338 {
 339   quit_flag = 0;
 340   immediate_quit = 0;
 341   bpstat_clear_actions(stop_bpstat);    /* Clear queued breakpoint commands */
 342   disable_current_display ();
 343   do_cleanups (ALL_CLEANUPS);
 344   (NORETURN void) longjmp (to_top_level, 1);
 345 }
 346
 347 /* Call FUNC with arg ARGS, catching any errors.
 348    If there is no error, return the value returned by FUNC.
 349    If there is an error, print ERRSTRING, print the specific error message,
 350                          then return zero.  */
 351
 352 int
 353 catch_errors (func, args, errstring)
 354      int (*func) PARAMS ((char *));
 355      char *args;
 356      char *errstring;
 357 {
 358   jmp_buf saved;
 359   int val;
 360   struct cleanup *saved_cleanup_chain;
 361   char *saved_error_pre_print;
 362
 363   saved_cleanup_chain = save_cleanups ();
 364   saved_error_pre_print = error_pre_print;
 365
 366   memcpy ((char *)saved, (char *)to_top_level, sizeof (jmp_buf));
 367   error_pre_print = errstring;
 368
 369   if (setjmp (to_top_level) == 0)
 370     val = (*func) (args);
 371   else
 372     val = 0;
 373
 374   restore_cleanups (saved_cleanup_chain);
 375
 376   error_pre_print = saved_error_pre_print;
 377   memcpy ((char *)to_top_level, (char *)saved, sizeof (jmp_buf));
 378   return val;
 379 }
 380
 381 /* Handler for SIGHUP.  */
 382
 383 static void
 384 disconnect (signo)
 385 int signo;
 386 {
 387   catch_errors (quit_cover, NULL, "Could not kill inferior process");
 388   signal (SIGHUP, SIG_DFL);
 389   kill (getpid (), SIGHUP);
 390 }
 391
 392 /* Just a little helper function for disconnect().  */
 393
 394 static int
 395 quit_cover (s)
 396 char *s;
 397 {
 398   caution = 0;          /* Throw caution to the wind -- we're exiting.
 399                            This prevents asking the user dumb questions.  */
 400   quit_command((char *)0, 0);
 401   return 0;
 402 }
 403 \f
 404 /* Clean up on error during a "source" command (or execution of a
 405    user-defined command).  */
 406
 407 static void
 408 source_cleanup (stream)
 409      FILE *stream;
 410 {
 411   /* Restore the previous input stream.  */
 412   instream = stream;
 413 }
 414
 415 /* Read commands from STREAM.  */
 416 static void
 417 read_command_file (stream)
 418      FILE *stream;
 419 {
 420   struct cleanup *cleanups;
 421
 422   cleanups = make_cleanup (source_cleanup, instream);
 423   instream = stream;
 424   command_loop ();
 425   do_cleanups (cleanups);
 426 }
 427 \f
 428 int
 429 main (argc, argv)
 430      int argc;
 431      char **argv;
 432 {
 433   int count;
 434   static int inhibit_gdbinit = 0;
 435   static int quiet = 0;
 436   static int batch = 0;
 437
 438   /* Pointers to various arguments from command line.  */
 439   char *symarg = NULL;
 440   char *execarg = NULL;
 441   char *corearg = NULL;
 442   char *cdarg = NULL;
 443   char *ttyarg = NULL;
 444
 445   /* Pointers to all arguments of +command option.  */
 446   char **cmdarg;
 447   /* Allocated size of cmdarg.  */
 448   int cmdsize;
 449   /* Number of elements of cmdarg used.  */
 450   int ncmd;
 451
 452   /* Indices of all arguments of +directory option.  */
 453   char **dirarg;
 454   /* Allocated size.  */
 455   int dirsize;
 456   /* Number of elements used.  */
 457   int ndir;
 458
 459   struct stat homebuf, cwdbuf;
 460   char *homedir, *homeinit;
 461
 462   register int i;
 463
 464   /* This needs to happen before the first use of malloc.  */
 465   init_malloc ((PTR) NULL);
 466
 467 #if defined (ALIGN_STACK_ON_STARTUP)
 468   i = (int) &count & 0x3;
 469   if (i != 0)
 470     alloca (4 - i);
 471 #endif
 472
 473   /* If error() is called from initialization code, just exit */
 474   if (setjmp (to_top_level)) {
 475     exit(1);
 476   }
 477
 478   cmdsize = 1;
 479   cmdarg = (char **) xmalloc (cmdsize * sizeof (*cmdarg));
 480   ncmd = 0;
 481   dirsize = 1;
 482   dirarg = (char **) xmalloc (dirsize * sizeof (*dirarg));
 483   ndir = 0;
 484
 485   quit_flag = 0;
 486   line = (char *) xmalloc (linesize);
 487   line[0] = '\0';               /* Terminate saved (now empty) cmd line */
 488   instream = stdin;
 489
 490   getcwd (dirbuf, sizeof (dirbuf));
 491   current_directory = dirbuf;
 492
 493 #ifdef SET_STACK_LIMIT_HUGE
 494   {
 495     struct rlimit rlim;
 496
 497     /* Set the stack limit huge so that alloca (particularly stringtab
 498      * in dbxread.c) does not fail. */
 499     getrlimit (RLIMIT_STACK, &rlim);
 500     original_stack_limit = rlim.rlim_cur;
 501     rlim.rlim_cur = rlim.rlim_max;
 502     setrlimit (RLIMIT_STACK, &rlim);
 503   }
 504 #endif /* SET_STACK_LIMIT_HUGE */
 505
 506   /* Parse arguments and options.  */
 507   {
 508     int c;
 509     static int print_help;
 510     /* When var field is 0, use flag field to record the equivalent
 511        short option (or arbitrary numbers starting at 10 for those
 512        with no equivalent).  */
 513     static struct option long_options[] =
 514       {
 515         {"readnow", no_argument, &readnow_symbol_files, 1},
 516         {"r", no_argument, &readnow_symbol_files, 1},
 517         {"mapped", no_argument, &mapped_symbol_files, 1},
 518         {"m", no_argument, &mapped_symbol_files, 1},
 519         {"quiet", no_argument, &quiet, 1},
 520         {"q", no_argument, &quiet, 1},
 521         {"nx", no_argument, &inhibit_gdbinit, 1},
 522         {"n", no_argument, &inhibit_gdbinit, 1},
 523         {"batch", no_argument, &batch, 1},
 524         {"epoch", no_argument, &epoch_interface, 1},
 525         {"fullname", no_argument, &frame_file_full_name, 1},
 526         {"f", no_argument, &frame_file_full_name, 1},
 527         {"help", no_argument, &print_help, 1},
 528         {"se", required_argument, 0, 10},
 529         {"symbols", required_argument, 0, 's'},
 530         {"s", required_argument, 0, 's'},
 531         {"exec", required_argument, 0, 'e'},
 532         {"e", required_argument, 0, 'e'},
 533         {"core", required_argument, 0, 'c'},
 534         {"c", required_argument, 0, 'c'},
 535         {"command", required_argument, 0, 'x'},
 536         {"x", required_argument, 0, 'x'},
 537         {"directory", required_argument, 0, 'd'},
 538         {"cd", required_argument, 0, 11},
 539         {"tty", required_argument, 0, 't'},
 540         {"baud", required_argument, 0, 'b'},
 541         {"b", required_argument, 0, 'b'},
 542 /* Allow machine descriptions to add more options... */
 543 #ifdef ADDITIONAL_OPTIONS
 544         ADDITIONAL_OPTIONS
 545 #endif
 546         {0, no_argument, 0, 0},
 547       };
 548
 549     while (1)
 550       {
 551         int option_index;
 552
 553         c = getopt_long_only (argc, argv, "",
 554                               long_options, &option_index);
 555         if (c == EOF)
 556           break;
 557
 558         /* Long option that takes an argument.  */
 559         if (c == 0 && long_options[option_index].flag == 0)
 560           c = long_options[option_index].val;
 561
 562         switch (c)
 563           {
 564           case 0:
 565             /* Long option that just sets a flag.  */
 566             break;
 567           case 10:
 568             symarg = optarg;
 569             execarg = optarg;
 570             break;
 571           case 11:
 572             cdarg = optarg;
 573             break;
 574           case 's':
 575             symarg = optarg;
 576             break;
 577           case 'e':
 578             execarg = optarg;
 579             break;
 580           case 'c':
 581             corearg = optarg;
 582             break;
 583           case 'x':
 584             cmdarg[ncmd++] = optarg;
 585             if (ncmd >= cmdsize)
 586               {
 587                 cmdsize *= 2;
 588                 cmdarg = (char **) xrealloc ((char *)cmdarg,
 589                                              cmdsize * sizeof (*cmdarg));
 590               }
 591             break;
 592           case 'd':
 593             dirarg[ndir++] = optarg;
 594             if (ndir >= dirsize)
 595               {
 596                 dirsize *= 2;
 597                 dirarg = (char **) xrealloc ((char *)dirarg,
 598                                              dirsize * sizeof (*dirarg));
 599               }
 600             break;
 601           case 't':
 602             ttyarg = optarg;
 603             break;
 604           case 'q':
 605             quiet = 1;
 606             break;
 607           case 'b':
 608             baud_rate = optarg;
 609             break;
 610 #ifdef ADDITIONAL_OPTION_CASES
 611           ADDITIONAL_OPTION_CASES
 612 #endif
 613           case '?':
 614             fprintf (stderr,
 615                      "Use `%s +help' for a complete list of options.\n",
 616                      argv[0]);
 617             exit (1);
 618           }
 619
 620       }
 621     if (print_help)
 622       {
 623         fputs ("\
 624 This is GDB, the GNU debugger.  Use the command\n\
 625     gdb [options] [executable [core-file]]\n\
 626 to enter the debugger.\n\
 627 \n\
 628 Options available are:\n\
 629   -help             Print this message.\n\
 630   -quiet            Do not print version number on startup.\n\
 631   -fullname         Output information used by emacs-GDB interface.\n\
 632   -epoch            Output information used by epoch emacs-GDB interface.\n\
 633   -batch            Exit after processing options.\n\
 634   -nx               Do not read .gdbinit file.\n\
 635   -tty=TTY          Use TTY for input/output by the program being debugged.\n\
 636   -cd=DIR           Change current directory to DIR.\n\
 637   -directory=DIR    Search for source files in DIR.\n\
 638   -command=FILE     Execute GDB commands from FILE.\n\
 639   -symbols=SYMFILE  Read symbols from SYMFILE.\n\
 640   -exec=EXECFILE    Use EXECFILE as the executable.\n\
 641   -se=FILE          Use FILE as symbol file and executable file.\n\
 642   -core=COREFILE    Analyze the core dump COREFILE.\n\
 643   -b BAUDRATE       Set serial port baud rate used for remote debugging.\n\
 644   -mapped           Use mapped symbol files if supported on this system.\n\
 645   -readnow          Fully read symbol files on first access.\n\
 646 ", stderr);
 647 #ifdef ADDITIONAL_OPTION_HELP
 648         fputs (ADDITIONAL_OPTION_HELP, stderr);
 649 #endif
 650         fputs ("\n\
 651 For more information, type \"help\" from within GDB, or consult the\n\
 652 GDB manual (available as on-line info or a printed manual).\n", stderr);
 653         /* Exiting after printing this message seems like
 654            the most useful thing to do.  */
 655         exit (0);
 656       }
 657
 658     /* OK, that's all the options.  The other arguments are filenames.  */
 659     count = 0;
 660     for (; optind < argc; optind++)
 661       switch (++count)
 662         {
 663         case 1:
 664           symarg = argv[optind];
 665           execarg = argv[optind];
 666           break;
 667         case 2:
 668           corearg = argv[optind];
 669           break;
 670         case 3:
 671           fprintf (stderr,
 672                    "Excess command line arguments ignored. (%s%s)\n",
 673                    argv[optind], (optind == argc - 1) ? "" : " ...");
 674           break;
 675         }
 676     if (batch)
 677       quiet = 1;
 678   }
 679
 680   /* Run the init function of each source file */
 681
 682   initialize_cmd_lists ();      /* This needs to be done first */
 683   initialize_all_files ();
 684   initialize_main ();           /* But that omits this file!  Do it now */
 685   init_signals ();
 686
 687   if (!quiet)
 688     {
 689       /* Print all the junk at the top, with trailing "..." if we are about
 690          to read a symbol file (possibly slowly).  */
 691       print_gnu_advertisement ();
 692       print_gdb_version ();
 693       if (symarg)
 694         printf_filtered ("..");
 695       wrap_here("");
 696       fflush (stdout);          /* Force to screen during slow operations */
 697     }
 698
 699   error_pre_print = "\n\n";
 700   /* We may get more than one warning, don't double space all of them... */
 701   warning_pre_print = "\nwarning: ";
 702
 703   /* We need a default language for parsing expressions, so simple things like
 704      "set width 0" won't fail if no language is explicitly set in a config file
 705      or implicitly set by reading an executable during startup. */
 706   set_language (language_c);
 707   expected_language = current_language; /* don't warn about the change.  */
 708
 709   /* Read and execute $HOME/.gdbinit file, if it exists.  This is done
 710      *before* all the command line arguments are processed; it sets
 711      global parameters, which are independent of what file you are
 712      debugging or what directory you are in.  */
 713   homedir = getenv ("HOME");
 714   if (homedir)
 715     {
 716       homeinit = (char *) alloca (strlen (getenv ("HOME")) +
 717                                   strlen (gdbinit) + 10);
 718       strcpy (homeinit, getenv ("HOME"));
 719       strcat (homeinit, "/");
 720       strcat (homeinit, gdbinit);
 721       if (!inhibit_gdbinit && access (homeinit, R_OK) == 0)
 722         {
 723           if (!setjmp (to_top_level))
 724             source_command (homeinit, 0);
 725         }
 726       do_cleanups (ALL_CLEANUPS);
 727
 728       /* Do stats; no need to do them elsewhere since we'll only
 729          need them if homedir is set.  Make sure that they are
 730          zero in case one of them fails (this guarantees that they
 731          won't match if either exists).  */
 732
 733       memset (&homebuf, 0, sizeof (struct stat));
 734       memset (&cwdbuf, 0, sizeof (struct stat));
 735
 736       stat (homeinit, &homebuf);
 737       stat (gdbinit, &cwdbuf); /* We'll only need this if
 738                                        homedir was set.  */
 739     }
 740
 741   /* Now perform all the actions indicated by the arguments.  */
 742   if (cdarg != NULL)
 743     {
 744       if (!setjmp (to_top_level))
 745         {
 746           cd_command (cdarg, 0);
 747           init_source_path ();
 748         }
 749     }
 750   do_cleanups (ALL_CLEANUPS);
 751
 752   for (i = 0; i < ndir; i++)
 753     if (!setjmp (to_top_level))
 754       directory_command (dirarg[i], 0);
 755   free ((PTR)dirarg);
 756   do_cleanups (ALL_CLEANUPS);
 757
 758   if (execarg != NULL
 759       && symarg != NULL
 760       && strcmp (execarg, symarg) == 0)
 761     {
 762       /* The exec file and the symbol-file are the same.  If we can't open
 763          it, better only print one error message.  */
 764       if (!setjmp (to_top_level))
 765         {
 766           exec_file_command (execarg, !batch);
 767           symbol_file_command (symarg, 0);
 768         }
 769     }
 770   else
 771     {
 772       if (execarg != NULL)
 773         if (!setjmp (to_top_level))
 774           exec_file_command (execarg, !batch);
 775       if (symarg != NULL)
 776         if (!setjmp (to_top_level))
 777           symbol_file_command (symarg, 0);
 778     }
 779   do_cleanups (ALL_CLEANUPS);
 780
 781   /* After the symbol file has been read, print a newline to get us
 782      beyond the copyright line...  But errors should still set off
 783      the error message with a (single) blank line.  */
 784   if (!quiet)
 785     printf_filtered ("\n");
 786   error_pre_print = "\n";
 787   warning_pre_print = "\nwarning: ";
 788
 789   if (corearg != NULL)
 790     if (!setjmp (to_top_level))
 791       core_file_command (corearg, !batch);
 792     else if (isdigit (corearg[0]) && !setjmp (to_top_level))
 793       attach_command (corearg, !batch);
 794   do_cleanups (ALL_CLEANUPS);
 795
 796   if (ttyarg != NULL)
 797     if (!setjmp (to_top_level))
 798       tty_command (ttyarg, !batch);
 799   do_cleanups (ALL_CLEANUPS);
 800
 801 #ifdef ADDITIONAL_OPTION_HANDLER
 802   ADDITIONAL_OPTION_HANDLER;
 803 #endif
 804
 805   /* Error messages should no longer be distinguished with extra output. */
 806   error_pre_print = 0;
 807   warning_pre_print = "warning: ";
 808
 809   /* Read the .gdbinit file in the current directory, *if* it isn't
 810      the same as the $HOME/.gdbinit file (it should exist, also).  */
 811
 812   if (!homedir
 813       || memcmp ((char *) &homebuf, (char *) &cwdbuf, sizeof (struct stat)))
 814     if (!inhibit_gdbinit && access (gdbinit, R_OK) == 0)
 815       {
 816         if (!setjmp (to_top_level))
 817           source_command (gdbinit, 0);
 818       }
 819   do_cleanups (ALL_CLEANUPS);
 820
 821   for (i = 0; i < ncmd; i++)
 822     {
 823       if (!setjmp (to_top_level))
 824         {
 825           if (cmdarg[i][0] == '-' && cmdarg[i][1] == '\0')
 826             read_command_file (stdin);
 827           else
 828             source_command (cmdarg[i], !batch);
 829           do_cleanups (ALL_CLEANUPS);
 830         }
 831     }
 832   free ((PTR)cmdarg);
 833
 834   /* Read in the old history after all the command files have been read. */
 835   initialize_history();
 836
 837   if (batch)
 838     {
 839       /* We have hit the end of the batch file.  */
 840       exit (0);
 841     }
 842
 843   /* Do any host- or target-specific hacks.  This is used for i960 targets
 844      to force the user to set a nindy target and spec its parameters.  */
 845
 846 #ifdef BEFORE_MAIN_LOOP_HOOK
 847   BEFORE_MAIN_LOOP_HOOK;
 848 #endif
 849
 850   /* The command loop.  */
 851
 852   while (1)
 853     {
 854       if (!setjmp (to_top_level))
 855         {
 856           do_cleanups (ALL_CLEANUPS);           /* Do complete cleanup */
 857           command_loop ();
 858           quit_command ((char *)0, instream == stdin);
 859         }
 860     }
 861   /* No exit -- exit is through quit_command.  */
 862 }
 863
 864 void
 865 execute_user_command (c, args)
 866      struct cmd_list_element *c;
 867      char *args;
 868 {
 869   register struct command_line *cmdlines;
 870   struct cleanup *old_chain;
 871
 872   if (args)
 873     error ("User-defined commands cannot take arguments.");
 874
 875   cmdlines = c->user_commands;
 876   if (cmdlines == 0)
 877     /* Null command */
 878     return;
 879
 880   /* Set the instream to 0, indicating execution of a
 881      user-defined function.  */
 882   old_chain = make_cleanup (source_cleanup, instream);
 883   instream = (FILE *) 0;
 884   while (cmdlines)
 885     {
 886       execute_command (cmdlines->line, 0);
 887       cmdlines = cmdlines->next;
 888     }
 889   do_cleanups (old_chain);
 890 }
 891
 892 /* Execute the line P as a command.
 893    Pass FROM_TTY as second argument to the defining function.  */
 894
 895 void
 896 execute_command (p, from_tty)
 897      char *p;
 898      int from_tty;
 899 {
 900   register struct cmd_list_element *c;
 901   register struct command_line *cmdlines;
 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 (SIGTSTP, 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;
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 && 0 != strcmp (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 && 0 != strcmp (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 ()
1894 {
1895   printf_filtered ("\
1896 GDB %s, Copyright 1992 Free Software Foundation, Inc.",
1897           version);
1898 }
1899
1900 /* ARGSUSED */
1901 static void
1902 show_version (args, from_tty)
1903      char *args;
1904      int from_tty;
1905 {
1906   immediate_quit++;
1907   print_gnu_advertisement ();
1908   print_gdb_version ();
1909   printf_filtered ("\n");
1910   immediate_quit--;
1911 }
1912 \f
1913 /* xgdb calls this to reprint the usual GDB prompt.  */
1914
1915 void
1916 print_prompt ()
1917 {
1918   printf ("%s", prompt);
1919   fflush (stdout);
1920 }
1921 \f
1922 static void
1923 quit_command (args, from_tty)
1924      char *args;
1925      int from_tty;
1926 {
1927   if (inferior_pid != 0 && target_has_execution)
1928     {
1929       if (query ("The program is running.  Quit anyway? "))
1930         {
1931           if (attach_flag)
1932             target_detach (args, from_tty);
1933           else
1934             target_kill ();
1935         }
1936       else
1937         error ("Not confirmed.");
1938     }
1939   /* Save the history information if it is appropriate to do so.  */
1940   if (write_history_p && history_filename)
1941     write_history (history_filename);
1942   exit (0);
1943 }
1944
1945 /* Returns whether GDB is running on a terminal and whether the user
1946    desires that questions be asked of them on that terminal.  */
1947
1948 int
1949 input_from_terminal_p ()
1950 {
1951   return gdb_has_a_terminal && (instream == stdin) & caution;
1952 }
1953 \f
1954 /* ARGSUSED */
1955 static void
1956 pwd_command (args, from_tty)
1957      char *args;
1958      int from_tty;
1959 {
1960   if (args) error ("The \"pwd\" command does not take an argument: %s", args);
1961   getcwd (dirbuf, sizeof (dirbuf));
1962
1963   if (strcmp (dirbuf, current_directory))
1964     printf ("Working directory %s\n (canonically %s).\n",
1965             current_directory, dirbuf);
1966   else
1967     printf ("Working directory %s.\n", current_directory);
1968 }
1969
1970 static void
1971 cd_command (dir, from_tty)
1972      char *dir;
1973      int from_tty;
1974 {
1975   int len;
1976   int change;
1977
1978   /* If the new directory is absolute, repeat is a no-op; if relative,
1979      repeat might be useful but is more likely to be a mistake.  */
1980   dont_repeat ();
1981
1982   if (dir == 0)
1983     error_no_arg ("new working directory");
1984
1985   dir = tilde_expand (dir);
1986   make_cleanup (free, dir);
1987
1988   if (chdir (dir) < 0)
1989     perror_with_name (dir);
1990
1991   len = strlen (dir);
1992   dir = savestring (dir, len - (len > 1 && dir[len-1] == '/'));
1993   if (dir[0] == '/')
1994     current_directory = dir;
1995   else
1996     {
1997       current_directory = concat (current_directory, "/", dir, NULL);
1998       free (dir);
1999     }
2000
2001   /* Now simplify any occurrences of `.' and `..' in the pathname.  */
2002
2003   change = 1;
2004   while (change)
2005     {
2006       char *p;
2007       change = 0;
2008
2009       for (p = current_directory; *p;)
2010         {
2011           if (!strncmp (p, "/./", 2)
2012               && (p[2] == 0 || p[2] == '/'))
2013             strcpy (p, p + 2);
2014           else if (!strncmp (p, "/..", 3)
2015                    && (p[3] == 0 || p[3] == '/')
2016                    && p != current_directory)
2017             {
2018               char *q = p;
2019               while (q != current_directory && q[-1] != '/') q--;
2020               if (q != current_directory)
2021                 {
2022                   strcpy (q-1, p+3);
2023                   p = q-1;
2024                 }
2025             }
2026           else p++;
2027         }
2028     }
2029
2030   forget_cached_source_info ();
2031
2032   if (from_tty)
2033     pwd_command ((char *) 0, 1);
2034 }
2035 \f
2036 /* ARGSUSED */
2037 static void
2038 source_command (args, from_tty)
2039      char *args;
2040      int from_tty;
2041 {
2042   FILE *stream;
2043   struct cleanup *cleanups;
2044   char *file = args;
2045
2046   if (file == 0)
2047     /* Let source without arguments read .gdbinit.  */
2048     file = gdbinit;
2049
2050   file = tilde_expand (file);
2051   make_cleanup (free, file);
2052
2053   stream = fopen (file, "r");
2054   if (stream == 0)
2055     perror_with_name (file);
2056
2057   cleanups = make_cleanup (fclose, stream);
2058
2059   read_command_file (stream);
2060
2061   do_cleanups (cleanups);
2062 }
2063
2064 /* ARGSUSED */
2065 static void
2066 echo_command (text, from_tty)
2067      char *text;
2068      int from_tty;
2069 {
2070   char *p = text;
2071   register int c;
2072
2073   if (text)
2074     while (c = *p++)
2075       {
2076         if (c == '\\')
2077           {
2078             /* \ at end of argument is used after spaces
2079                so they won't be lost.  */
2080             if (*p == 0)
2081               return;
2082
2083             c = parse_escape (&p);
2084             if (c >= 0)
2085               printf_filtered ("%c", c);
2086           }
2087         else
2088           printf_filtered ("%c", c);
2089       }
2090
2091   /* Force this output to appear now.  */
2092   wrap_here ("");
2093   fflush (stdout);
2094 }
2095
2096 \f
2097 /* Functions to manipulate command line editing control variables.  */
2098
2099 /* Number of commands to print in each call to show_commands.  */
2100 #define Hist_print 10
2101 static void
2102 show_commands (args, from_tty)
2103      char *args;
2104      int from_tty;
2105 {
2106   /* Index for history commands.  Relative to history_base.  */
2107   int offset;
2108
2109   /* Number of the history entry which we are planning to display next.
2110      Relative to history_base.  */
2111   static int num = 0;
2112
2113   /* The first command in the history which doesn't exist (i.e. one more
2114      than the number of the last command).  Relative to history_base.  */
2115   int hist_len;
2116
2117   extern struct _hist_entry *history_get PARAMS ((int));
2118   extern int history_base;
2119
2120   /* Print out some of the commands from the command history.  */
2121   /* First determine the length of the history list.  */
2122   hist_len = history_size;
2123   for (offset = 0; offset < history_size; offset++)
2124     {
2125       if (!history_get (history_base + offset))
2126         {
2127           hist_len = offset;
2128           break;
2129         }
2130     }
2131
2132   if (args)
2133     {
2134       if (args[0] == '+' && args[1] == '\0')
2135         /* "info editing +" should print from the stored position.  */
2136         ;
2137       else
2138         /* "info editing <exp>" should print around command number <exp>.  */
2139         num = (parse_and_eval_address (args) - history_base) - Hist_print / 2;
2140     }
2141   /* "show commands" means print the last Hist_print commands.  */
2142   else
2143     {
2144       num = hist_len - Hist_print;
2145     }
2146
2147   if (num < 0)
2148     num = 0;
2149
2150   /* If there are at least Hist_print commands, we want to display the last
2151      Hist_print rather than, say, the last 6.  */
2152   if (hist_len - num < Hist_print)
2153     {
2154       num = hist_len - Hist_print;
2155       if (num < 0)
2156         num = 0;
2157     }
2158
2159   for (offset = num; offset < num + Hist_print && offset < hist_len; offset++)
2160     {
2161       printf_filtered ("%5d  %s\n", history_base + offset,
2162               (history_get (history_base + offset))->line);
2163     }
2164
2165   /* The next command we want to display is the next one that we haven't
2166      displayed yet.  */
2167   num += Hist_print;
2168
2169   /* If the user repeats this command with return, it should do what
2170      "show commands +" does.  This is unnecessary if arg is null,
2171      because "show commands +" is not useful after "show commands".  */
2172   if (from_tty && args)
2173     {
2174       args[0] = '+';
2175       args[1] = '\0';
2176     }
2177 }
2178
2179 /* Called by do_setshow_command.  */
2180 /* ARGSUSED */
2181 static void
2182 set_history_size_command (args, from_tty, c)
2183      char *args;
2184      int from_tty;
2185      struct cmd_list_element *c;
2186 {
2187   if (history_size == UINT_MAX)
2188     unstifle_history ();
2189   else if (history_size >= 0)
2190     stifle_history (history_size);
2191   else
2192     {
2193       history_size = UINT_MAX;
2194       error ("History size must be non-negative");
2195     }
2196 }
2197
2198 /* ARGSUSED */
2199 static void
2200 set_history (args, from_tty)
2201      char *args;
2202      int from_tty;
2203 {
2204   printf ("\"set history\" must be followed by the name of a history subcommand.\n");
2205   help_list (sethistlist, "set history ", -1, stdout);
2206 }
2207
2208 /* ARGSUSED */
2209 static void
2210 show_history (args, from_tty)
2211      char *args;
2212      int from_tty;
2213 {
2214   cmd_show_list (showhistlist, from_tty, "");
2215 }
2216
2217 int info_verbose = 0;           /* Default verbose msgs off */
2218
2219 /* Called by do_setshow_command.  An elaborate joke.  */
2220 /* ARGSUSED */
2221 static void
2222 set_verbose (args, from_tty, c)
2223      char *args;
2224      int from_tty;
2225      struct cmd_list_element *c;
2226 {
2227   char *cmdname = "verbose";
2228   struct cmd_list_element *showcmd;
2229
2230   showcmd = lookup_cmd_1 (&cmdname, showlist, NULL, 1);
2231
2232   if (info_verbose)
2233     {
2234       c->doc = "Set verbose printing of informational messages.";
2235       showcmd->doc = "Show verbose printing of informational messages.";
2236     }
2237   else
2238     {
2239       c->doc = "Set verbosity.";
2240       showcmd->doc = "Show verbosity.";
2241     }
2242 }
2243
2244 static void
2245 float_handler (signo)
2246 int signo;
2247 {
2248   /* This message is based on ANSI C, section 4.7.  Note that integer
2249      divide by zero causes this, so "float" is a misnomer.  */
2250   error ("Erroneous arithmetic operation.");
2251 }
2252
2253 /* Return whether we are running a batch file or from terminal.  */
2254 int
2255 batch_mode ()
2256 {
2257   return !(instream == stdin && ISATTY (stdin));
2258 }
2259
2260 \f
2261 static void
2262 initialize_cmd_lists ()
2263 {
2264   cmdlist = NULL;
2265   infolist = NULL;
2266   enablelist = NULL;
2267   disablelist = NULL;
2268   deletelist = NULL;
2269   enablebreaklist = NULL;
2270   setlist = NULL;
2271   unsetlist = NULL;
2272   showlist = NULL;
2273   sethistlist = NULL;
2274   showhistlist = NULL;
2275   unsethistlist = NULL;
2276 #if MAINTENANCE_CMDS
2277   maintenancelist = NULL;
2278   maintenanceinfolist = NULL;
2279   maintenanceprintlist = NULL;
2280 #endif
2281   setprintlist = NULL;
2282   showprintlist = NULL;
2283   setchecklist = NULL;
2284   showchecklist = NULL;
2285 }
2286
2287 /* Init the history buffer.  Note that we are called after the init file(s)
2288  * have been read so that the user can change the history file via his
2289  * .gdbinit file (for instance).  The GDBHISTFILE environment variable
2290  * overrides all of this.
2291  */
2292
2293 static void
2294 initialize_history()
2295 {
2296   char *tmpenv;
2297
2298   tmpenv = getenv ("HISTSIZE");
2299   if (tmpenv)
2300     history_size = atoi (tmpenv);
2301   else if (!history_size)
2302     history_size = 256;
2303
2304   stifle_history (history_size);
2305
2306   tmpenv = getenv ("GDBHISTFILE");
2307   if (tmpenv)
2308     history_filename = savestring (tmpenv, strlen(tmpenv));
2309   else if (!history_filename) {
2310     /* We include the current directory so that if the user changes
2311        directories the file written will be the same as the one
2312        that was read.  */
2313     history_filename = concat (current_directory, "/.gdb_history", NULL);
2314   }
2315   read_history (history_filename);
2316 }
2317
2318 static void
2319 initialize_main ()
2320 {
2321   struct cmd_list_element *c;
2322
2323 #ifdef DEFAULT_PROMPT
2324   prompt = savestring (DEFAULT_PROMPT, strlen(DEFAULT_PROMPT));
2325 #else
2326   prompt = savestring ("(gdb) ", 6);
2327 #endif
2328
2329   /* Set the important stuff up for command editing.  */
2330   command_editing_p = 1;
2331   history_expansion_p = 0;
2332   write_history_p = 0;
2333
2334   /* Setup important stuff for command line editing.  */
2335   rl_completion_entry_function = (int (*)()) symbol_completion_function;
2336   rl_completer_word_break_characters = gdb_completer_word_break_characters;
2337   rl_completer_quote_characters = gdb_completer_quote_characters;
2338   rl_readline_name = "gdb";
2339
2340   /* Define the classes of commands.
2341      They will appear in the help list in the reverse of this order.  */
2342
2343   add_cmd ("internals", class_maintenance, NO_FUNCTION,
2344            "Maintenance commands.\n\
2345 Some gdb commands are provided just for use by gdb maintainers.\n\
2346 These commands are subject to frequent change, and may not be as\n\
2347 well documented as user commands.",
2348            &cmdlist);
2349   add_cmd ("obscure", class_obscure, NO_FUNCTION, "Obscure features.", &cmdlist);
2350   add_cmd ("aliases", class_alias, NO_FUNCTION, "Aliases of other commands.", &cmdlist);
2351   add_cmd ("user-defined", class_user, NO_FUNCTION, "User-defined commands.\n\
2352 The commands in this class are those defined by the user.\n\
2353 Use the \"define\" command to define a command.", &cmdlist);
2354   add_cmd ("support", class_support, NO_FUNCTION, "Support facilities.", &cmdlist);
2355   add_cmd ("status", class_info, NO_FUNCTION, "Status inquiries.", &cmdlist);
2356   add_cmd ("files", class_files, NO_FUNCTION, "Specifying and examining files.", &cmdlist);
2357   add_cmd ("breakpoints", class_breakpoint, NO_FUNCTION, "Making program stop at certain points.", &cmdlist);
2358   add_cmd ("data", class_vars, NO_FUNCTION, "Examining data.", &cmdlist);
2359   add_cmd ("stack", class_stack, NO_FUNCTION, "Examining the stack.\n\
2360 The stack is made up of stack frames.  Gdb assigns numbers to stack frames\n\
2361 counting from zero for the innermost (currently executing) frame.\n\n\
2362 At any time gdb identifies one frame as the \"selected\" frame.\n\
2363 Variable lookups are done with respect to the selected frame.\n\
2364 When the program being debugged stops, gdb selects the innermost frame.\n\
2365 The commands below can be used to select other frames by number or address.",
2366            &cmdlist);
2367   add_cmd ("running", class_run, NO_FUNCTION, "Running the program.", &cmdlist);
2368
2369   add_com ("pwd", class_files, pwd_command,
2370            "Print working directory.  This is used for your program as well.");
2371   add_com ("cd", class_files, cd_command,
2372            "Set working directory to DIR for debugger and program being debugged.\n\
2373 The change does not take effect for the program being debugged\n\
2374 until the next time it is started.");
2375
2376   add_show_from_set
2377     (add_set_cmd ("prompt", class_support, var_string, (char *)&prompt,
2378            "Set gdb's prompt",
2379            &setlist),
2380      &showlist);
2381
2382   add_com ("echo", class_support, echo_command,
2383            "Print a constant string.  Give string as argument.\n\
2384 C escape sequences may be used in the argument.\n\
2385 No newline is added at the end of the argument;\n\
2386 use \"\\n\" if you want a newline to be printed.\n\
2387 Since leading and trailing whitespace are ignored in command arguments,\n\
2388 if you want to print some you must use \"\\\" before leading whitespace\n\
2389 to be printed or after trailing whitespace.");
2390   add_com ("document", class_support, document_command,
2391            "Document a user-defined command.\n\
2392 Give command name as argument.  Give documentation on following lines.\n\
2393 End with a line of just \"end\".");
2394   add_com ("define", class_support, define_command,
2395            "Define a new command name.  Command name is argument.\n\
2396 Definition appears on following lines, one command per line.\n\
2397 End with a line of just \"end\".\n\
2398 Use the \"document\" command to give documentation for the new command.\n\
2399 Commands defined in this way do not take arguments.");
2400
2401 #ifdef __STDC__
2402   add_com ("source", class_support, source_command,
2403            "Read commands from a file named FILE.\n\
2404 Note that the file \"" GDBINIT_FILENAME "\" is read automatically in this way\n\
2405 when gdb is started.");
2406 #else
2407   /* Punt file name, we can't help it easily.  */
2408   add_com ("source", class_support, source_command,
2409            "Read commands from a file named FILE.\n\
2410 Note that the file \".gdbinit\" is read automatically in this way\n\
2411 when gdb is started.");
2412 #endif
2413
2414   add_com ("quit", class_support, quit_command, "Exit gdb.");
2415   add_com ("help", class_support, help_command, "Print list of commands.");
2416   add_com_alias ("q", "quit", class_support, 1);
2417   add_com_alias ("h", "help", class_support, 1);
2418
2419
2420   c = add_set_cmd ("verbose", class_support, var_boolean, (char *)&info_verbose,
2421                    "Set ",
2422                    &setlist),
2423   add_show_from_set (c, &showlist);
2424   c->function.sfunc = set_verbose;
2425   set_verbose (NULL, 0, c);
2426
2427   add_show_from_set
2428     (add_set_cmd ("editing", class_support, var_boolean, (char *)&command_editing_p,
2429            "Set editing of command lines as they are typed.\n\
2430 Use \"on\" to enable to enable the editing, and \"off\" to disable it.\n\
2431 Without an argument, command line editing is enabled.  To edit, use\n\
2432 EMACS-like or VI-like commands like control-P or ESC.", &setlist),
2433      &showlist);
2434
2435   add_prefix_cmd ("history", class_support, set_history,
2436                   "Generic command for setting command history parameters.",
2437                   &sethistlist, "set history ", 0, &setlist);
2438   add_prefix_cmd ("history", class_support, show_history,
2439                   "Generic command for showing command history parameters.",
2440                   &showhistlist, "show history ", 0, &showlist);
2441
2442   add_show_from_set
2443     (add_set_cmd ("expansion", no_class, var_boolean, (char *)&history_expansion_p,
2444            "Set history expansion on command input.\n\
2445 Without an argument, history expansion is enabled.", &sethistlist),
2446      &showhistlist);
2447
2448   add_show_from_set
2449     (add_set_cmd ("save", no_class, var_boolean, (char *)&write_history_p,
2450            "Set saving of the history record on exit.\n\
2451 Use \"on\" to enable to enable the saving, and \"off\" to disable it.\n\
2452 Without an argument, saving is enabled.", &sethistlist),
2453      &showhistlist);
2454
2455   c = add_set_cmd ("size", no_class, var_uinteger, (char *)&history_size,
2456                    "Set the size of the command history, \n\
2457 ie. the number of previous commands to keep a record of.", &sethistlist);
2458   add_show_from_set (c, &showhistlist);
2459   c->function.sfunc = set_history_size_command;
2460
2461   add_show_from_set
2462     (add_set_cmd ("filename", no_class, var_filename, (char *)&history_filename,
2463            "Set the filename in which to record the command history\n\
2464  (the list of previous commands of which a record is kept).", &sethistlist),
2465      &showhistlist);
2466
2467   add_show_from_set
2468     (add_set_cmd ("confirm", class_support, var_boolean,
2469                   (char *)&caution,
2470                   "Set whether to confirm potentially dangerous operations.",
2471                   &setlist),
2472      &showlist);
2473
2474   add_prefix_cmd ("info", class_info, info_command,
2475         "Generic command for showing things about the program being debugged.",
2476                   &infolist, "info ", 0, &cmdlist);
2477   add_com_alias ("i", "info", class_info, 1);
2478
2479   add_prefix_cmd ("show", class_info, show_command,
2480                   "Generic command for showing things about the debugger.",
2481                   &showlist, "show ", 0, &cmdlist);
2482   /* Another way to get at the same thing.  */
2483   add_info ("set", show_command, "Show all GDB settings.");
2484
2485   add_cmd ("commands", no_class, show_commands,
2486            "Show the the history of commands you typed.\n\
2487 You can supply a command number to start with, or a `+' to start after\n\
2488 the previous command number shown.",
2489            &showlist);
2490
2491   add_cmd ("version", no_class, show_version,
2492            "Show what version of GDB this is.", &showlist);
2493 }