gdb/command.h

   1 /* Header file for command creation.
   2
   3    Copyright (C) 1986-2021 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  17
  18 #if !defined (COMMAND_H)
  19 #define COMMAND_H 1
  20
  21 #include "gdbsupport/gdb_vecs.h"
  22 #include "gdbsupport/scoped_restore.h"
  23
  24 struct completion_tracker;
  25
  26 /* This file defines the public interface for any code wanting to
  27    create commands.  */
  28
  29 /* Command classes are top-level categories into which commands are
  30    broken down for "help" purposes.
  31
  32    The class_alias is used for the user-defined aliases, defined
  33    using the "alias" command.
  34
  35    Aliases pre-defined by GDB (e.g. the alias "bt" of the "backtrace" command)
  36    are not using the class_alias.
  37    Different pre-defined aliases of the same command do not necessarily
  38    have the same classes.  For example, class_stack is used for the
  39    "backtrace" and its "bt" alias", while "info stack" (also an alias
  40    of "backtrace" uses class_info.  */
  41
  42 enum command_class
  43 {
  44   /* Classes of commands followed by a comment giving the name
  45      to use in "help <classname>".
  46      Note that help accepts unambiguous abbreviated class names.  */
  47
  48   /* Special classes to help_list */
  49   class_deprecated = -3,
  50   all_classes = -2,  /* help without <classname> */
  51   all_commands = -1, /* all */
  52
  53   /* Classes of commands */
  54   no_class = -1,
  55   class_run = 0,     /* running */
  56   class_vars,        /* data */
  57   class_stack,       /* stack */
  58   class_files,       /* files */
  59   class_support,     /* support */
  60   class_info,        /* status */
  61   class_breakpoint,  /* breakpoints */
  62   class_trace,       /* tracepoints */
  63   class_alias,       /* aliases */
  64   class_bookmark,
  65   class_obscure,     /* obscure */
  66   class_maintenance, /* internals */
  67   class_tui,         /* text-user-interface */
  68   class_user,        /* user-defined */
  69
  70   /* Used for "show" commands that have no corresponding "set" command.  */
  71   no_set_class
  72 };
  73
  74 /* Types of "set" or "show" command.  */
  75 typedef enum var_types
  76   {
  77     /* "on" or "off".  *VAR is a bool which is true for on,
  78        false for off.  */
  79     var_boolean,
  80
  81     /* "on" / "true" / "enable" or "off" / "false" / "disable" or
  82        "auto.  *VAR is an ``enum auto_boolean''.  NOTE: In general a
  83        custom show command will need to be implemented - one that for
  84        "auto" prints both the "auto" and the current auto-selected
  85        value.  */
  86     var_auto_boolean,
  87
  88     /* Unsigned Integer.  *VAR is an unsigned int.  The user can type
  89        0 to mean "unlimited", which is stored in *VAR as UINT_MAX.  */
  90     var_uinteger,
  91
  92     /* Like var_uinteger but signed.  *VAR is an int.  The user can
  93        type 0 to mean "unlimited", which is stored in *VAR as
  94        INT_MAX.  The only remaining use of it is the Python API.
  95        Don't use it elsewhere.  */
  96     var_integer,
  97
  98     /* String which the user enters with escapes (e.g. the user types
  99        \n and it is a real newline in the stored string).
 100        *VAR is a malloc'd string, or NULL if the string is empty.  */
 101     var_string,
 102     /* String which stores what the user types verbatim.
 103        *VAR is a malloc'd string, or NULL if the string is empty.  */
 104     var_string_noescape,
 105     /* String which stores a filename.  (*VAR) is a malloc'd string,
 106        or "" if the string was empty.  */
 107     var_optional_filename,
 108     /* String which stores a filename.  (*VAR) is a malloc'd
 109        string.  */
 110     var_filename,
 111     /* ZeroableInteger.  *VAR is an int.  Like var_integer except
 112        that zero really means zero.  */
 113     var_zinteger,
 114     /* ZeroableUnsignedInteger.  *VAR is an unsigned int.  Zero really
 115        means zero.  */
 116     var_zuinteger,
 117     /* ZeroableUnsignedInteger with unlimited value.  *VAR is an int,
 118        but its range is [0, INT_MAX].  -1 stands for unlimited and
 119        other negative numbers are not allowed.  */
 120     var_zuinteger_unlimited,
 121     /* Enumerated type.  Can only have one of the specified values.
 122        *VAR is a char pointer to the name of the element that we
 123        find.  */
 124     var_enum
 125   }
 126 var_types;
 127
 128 /* This structure records one command'd definition.  */
 129 struct cmd_list_element;
 130
 131 typedef void cmd_const_cfunc_ftype (const char *args, int from_tty);
 132
 133 /* This structure specifies notifications to be suppressed by a cli
 134    command interpreter.  */
 135
 136 struct cli_suppress_notification
 137 {
 138   /* Inferior, thread, frame selected notification suppressed?  */
 139   int user_selected_context;
 140 };
 141
 142 extern struct cli_suppress_notification cli_suppress_notification;
 143
 144 /* Forward-declarations of the entry-points of cli/cli-decode.c.  */
 145
 146 /* API to the manipulation of command lists.  */
 147
 148 /* Return TRUE if NAME is a valid user-defined command name.
 149    This is a stricter subset of all gdb commands,
 150    see find_command_name_length.  */
 151
 152 extern bool valid_user_defined_cmd_name_p (const char *name);
 153
 154 /* Return TRUE if C is a valid command character.  */
 155
 156 extern bool valid_cmd_char_p (int c);
 157
 158 /* Const-correct variant of the above.  */
 159
 160 extern struct cmd_list_element *add_cmd (const char *, enum command_class,
 161                                          cmd_const_cfunc_ftype *fun,
 162                                          const char *,
 163                                          struct cmd_list_element **);
 164
 165 /* Like add_cmd, but no command function is specified.  */
 166
 167 extern struct cmd_list_element *add_cmd (const char *, enum command_class,
 168                                          const char *,
 169                                          struct cmd_list_element **);
 170
 171 extern struct cmd_list_element *add_cmd_suppress_notification
 172                         (const char *name, enum command_class theclass,
 173                          cmd_const_cfunc_ftype *fun, const char *doc,
 174                          struct cmd_list_element **list,
 175                          int *suppress_notification);
 176
 177 extern struct cmd_list_element *add_alias_cmd (const char *, const char *,
 178                                                enum command_class, int,
 179                                                struct cmd_list_element **);
 180
 181 extern struct cmd_list_element *add_alias_cmd (const char *,
 182                                                cmd_list_element *,
 183                                                enum command_class, int,
 184                                                struct cmd_list_element **);
 185
 186
 187 extern struct cmd_list_element *add_prefix_cmd (const char *, enum command_class,
 188                                                 cmd_const_cfunc_ftype *fun,
 189                                                 const char *,
 190                                                 struct cmd_list_element **,
 191                                                 const char *, int,
 192                                                 struct cmd_list_element **);
 193
 194 /* Like add_prefix_cmd, but sets the callback to a function that
 195    simply calls help_list.  */
 196
 197 extern struct cmd_list_element *add_basic_prefix_cmd
 198   (const char *, enum command_class, const char *, struct cmd_list_element **,
 199    const char *, int, struct cmd_list_element **);
 200
 201 /* Like add_prefix_cmd, but useful for "show" prefixes.  This sets the
 202    callback to a function that simply calls cmd_show_list.  */
 203
 204 extern struct cmd_list_element *add_show_prefix_cmd
 205   (const char *, enum command_class, const char *, struct cmd_list_element **,
 206    const char *, int, struct cmd_list_element **);
 207
 208 extern struct cmd_list_element *add_prefix_cmd_suppress_notification
 209                         (const char *name, enum command_class theclass,
 210                          cmd_const_cfunc_ftype *fun,
 211                          const char *doc, struct cmd_list_element **prefixlist,
 212                          const char *prefixname, int allow_unknown,
 213                          struct cmd_list_element **list,
 214                          int *suppress_notification);
 215
 216 extern struct cmd_list_element *add_abbrev_prefix_cmd (const char *,
 217                                                        enum command_class,
 218                                                        cmd_const_cfunc_ftype *fun,
 219                                                        const char *,
 220                                                        struct cmd_list_element
 221                                                        **, const char *, int,
 222                                                        struct cmd_list_element
 223                                                        **);
 224
 225 typedef void cmd_const_sfunc_ftype (const char *args, int from_tty,
 226                                     struct cmd_list_element *c);
 227 extern void set_cmd_sfunc (struct cmd_list_element *cmd,
 228                            cmd_const_sfunc_ftype *sfunc);
 229
 230 /* A completion routine.  Add possible completions to tracker.
 231
 232    TEXT is the text beyond what was matched for the command itself
 233    (leading whitespace is skipped).  It stops where we are supposed to
 234    stop completing (rl_point) and is '\0' terminated.  WORD points in
 235    the same buffer as TEXT, and completions should be returned
 236    relative to this position.  For example, suppose TEXT is "foo" and
 237    we want to complete to "foobar".  If WORD is "oo", return "oobar";
 238    if WORD is "baz/foo", return "baz/foobar".  */
 239 typedef void completer_ftype (struct cmd_list_element *,
 240                               completion_tracker &tracker,
 241                               const char *text, const char *word);
 242
 243 /* Same, but for set_cmd_completer_handle_brkchars.  */
 244 typedef void completer_handle_brkchars_ftype (struct cmd_list_element *,
 245                                               completion_tracker &tracker,
 246                                               const char *text, const char *word);
 247
 248 extern void set_cmd_completer (struct cmd_list_element *, completer_ftype *);
 249
 250 /* Set the completer_handle_brkchars callback.  */
 251
 252 extern void set_cmd_completer_handle_brkchars (struct cmd_list_element *,
 253                                                completer_handle_brkchars_ftype *);
 254
 255 /* HACK: cagney/2002-02-23: Code, mostly in tracepoints.c, grubs
 256    around in cmd objects to test the value of the commands sfunc().  */
 257 extern int cmd_cfunc_eq (struct cmd_list_element *cmd,
 258                          cmd_const_cfunc_ftype *cfun);
 259
 260 /* Each command object has a local context attached to it.  */
 261 extern void set_cmd_context (struct cmd_list_element *cmd,
 262                              void *context);
 263 extern void *get_cmd_context (struct cmd_list_element *cmd);
 264
 265
 266 /* Execute CMD's pre/post hook.  Throw an error if the command fails.
 267    If already executing this pre/post hook, or there is no pre/post
 268    hook, the call is silently ignored.  */
 269 extern void execute_cmd_pre_hook (struct cmd_list_element *cmd);
 270 extern void execute_cmd_post_hook (struct cmd_list_element *cmd);
 271
 272 /* Flag for an ambiguous cmd_list result.  */
 273 #define CMD_LIST_AMBIGUOUS ((struct cmd_list_element *) -1)
 274
 275 extern struct cmd_list_element *lookup_cmd (const char **,
 276                                             struct cmd_list_element *,
 277                                             const char *,
 278                                             std::string *,
 279                                             int, int);
 280
 281 /* This routine takes a line of TEXT and a CLIST in which to start the
 282    lookup.  When it returns it will have incremented the text pointer past
 283    the section of text it matched, set *RESULT_LIST to point to the list in
 284    which the last word was matched, and will return a pointer to the cmd
 285    list element which the text matches.  It will return NULL if no match at
 286    all was possible.  It will return -1 (cast appropriately, ick) if ambigous
 287    matches are possible; in this case *RESULT_LIST will be set to point to
 288    the list in which there are ambiguous choices (and *TEXT will be set to
 289    the ambiguous text string).
 290
 291    if DEFAULT_ARGS is not null, *DEFAULT_ARGS is set to the found command
 292    default args (possibly empty).
 293
 294    If the located command was an abbreviation, this routine returns the base
 295    command of the abbreviation.  Note that *DEFAULT_ARGS will contain the
 296    default args defined for the alias.
 297
 298    It does no error reporting whatsoever; control will always return
 299    to the superior routine.
 300
 301    In the case of an ambiguous return (-1), *RESULT_LIST will be set to point
 302    at the prefix_command (ie. the best match) *or* (special case) will be NULL
 303    if no prefix command was ever found.  For example, in the case of "info a",
 304    "info" matches without ambiguity, but "a" could be "args" or "address", so
 305    *RESULT_LIST is set to the cmd_list_element for "info".  So in this case
 306    RESULT_LIST should not be interpreted as a pointer to the beginning of a
 307    list; it simply points to a specific command.  In the case of an ambiguous
 308    return *TEXT is advanced past the last non-ambiguous prefix (e.g.
 309    "info t" can be "info types" or "info target"; upon return *TEXT has been
 310    advanced past "info ").
 311
 312    If RESULT_LIST is NULL, don't set *RESULT_LIST (but don't otherwise
 313    affect the operation).
 314
 315    This routine does *not* modify the text pointed to by TEXT.
 316
 317    If IGNORE_HELP_CLASSES is nonzero, ignore any command list elements which
 318    are actually help classes rather than commands (i.e. the function field of
 319    the struct cmd_list_element is NULL).
 320
 321    When LOOKUP_FOR_COMPLETION_P is true the completion is being requested
 322    for the completion engine, no warnings should be printed.  */
 323
 324 extern struct cmd_list_element *lookup_cmd_1
 325         (const char **text, struct cmd_list_element *clist,
 326          struct cmd_list_element **result_list, std::string *default_args,
 327          int ignore_help_classes, bool lookup_for_completion_p = false);
 328
 329 extern struct cmd_list_element *deprecate_cmd (struct cmd_list_element *,
 330                                                const char * );
 331
 332 extern void deprecated_cmd_warning (const char *, struct cmd_list_element *);
 333
 334 extern int lookup_cmd_composition (const char *text,
 335                                    struct cmd_list_element **alias,
 336                                    struct cmd_list_element **prefix_cmd,
 337                                    struct cmd_list_element **cmd);
 338
 339 extern struct cmd_list_element *add_com (const char *, enum command_class,
 340                                          cmd_const_cfunc_ftype *fun,
 341                                          const char *);
 342
 343 extern struct cmd_list_element *add_com_alias (const char *, const char *,
 344                                                enum command_class, int);
 345
 346 extern struct cmd_list_element *add_com_suppress_notification
 347                        (const char *name, enum command_class theclass,
 348                         cmd_const_cfunc_ftype *fun, const char *doc,
 349                         int *supress_notification);
 350
 351 extern struct cmd_list_element *add_info (const char *,
 352                                           cmd_const_cfunc_ftype *fun,
 353                                           const char *);
 354
 355 extern struct cmd_list_element *add_info_alias (const char *, const char *,
 356                                                 int);
 357
 358 extern void complete_on_cmdlist (struct cmd_list_element *,
 359                                  completion_tracker &tracker,
 360                                  const char *, const char *, int);
 361
 362 extern void complete_on_enum (completion_tracker &tracker,
 363                               const char *const *enumlist,
 364                               const char *, const char *);
 365
 366 /* Functions that implement commands about CLI commands.  */
 367
 368 extern void help_list (struct cmd_list_element *, const char *,
 369                        enum command_class, struct ui_file *);
 370
 371 /* Method for show a set/show variable's VALUE on FILE.  If this
 372    method isn't supplied deprecated_show_value_hack() is called (which
 373    is not good).  */
 374 typedef void (show_value_ftype) (struct ui_file *file,
 375                                  int from_tty,
 376                                  struct cmd_list_element *cmd,
 377                                  const char *value);
 378 /* NOTE: i18n: This function is not i18n friendly.  Callers should
 379    instead print the value out directly.  */
 380 extern show_value_ftype deprecated_show_value_hack;
 381
 382 extern void add_setshow_enum_cmd (const char *name,
 383                                   enum command_class theclass,
 384                                   const char *const *enumlist,
 385                                   const char **var,
 386                                   const char *set_doc,
 387                                   const char *show_doc,
 388                                   const char *help_doc,
 389                                   cmd_const_sfunc_ftype *set_func,
 390                                   show_value_ftype *show_func,
 391                                   struct cmd_list_element **set_list,
 392                                   struct cmd_list_element **show_list,
 393                                   void *context = nullptr);
 394
 395 extern void add_setshow_auto_boolean_cmd (const char *name,
 396                                           enum command_class theclass,
 397                                           enum auto_boolean *var,
 398                                           const char *set_doc,
 399                                           const char *show_doc,
 400                                           const char *help_doc,
 401                                           cmd_const_sfunc_ftype *set_func,
 402                                           show_value_ftype *show_func,
 403                                           struct cmd_list_element **set_list,
 404                                           struct cmd_list_element **show_list);
 405
 406 extern cmd_list_element *
 407   add_setshow_boolean_cmd (const char *name,
 408                            enum command_class theclass,
 409                            bool *var,
 410                            const char *set_doc, const char *show_doc,
 411                            const char *help_doc,
 412                            cmd_const_sfunc_ftype *set_func,
 413                            show_value_ftype *show_func,
 414                            struct cmd_list_element **set_list,
 415                            struct cmd_list_element **show_list);
 416
 417 extern void add_setshow_filename_cmd (const char *name,
 418                                       enum command_class theclass,
 419                                       char **var,
 420                                       const char *set_doc,
 421                                       const char *show_doc,
 422                                       const char *help_doc,
 423                                       cmd_const_sfunc_ftype *set_func,
 424                                       show_value_ftype *show_func,
 425                                       struct cmd_list_element **set_list,
 426                                       struct cmd_list_element **show_list);
 427
 428 extern void add_setshow_string_cmd (const char *name,
 429                                     enum command_class theclass,
 430                                     char **var,
 431                                     const char *set_doc,
 432                                     const char *show_doc,
 433                                     const char *help_doc,
 434                                     cmd_const_sfunc_ftype *set_func,
 435                                     show_value_ftype *show_func,
 436                                     struct cmd_list_element **set_list,
 437                                     struct cmd_list_element **show_list);
 438
 439 extern struct cmd_list_element *add_setshow_string_noescape_cmd
 440                       (const char *name,
 441                        enum command_class theclass,
 442                        char **var,
 443                        const char *set_doc,
 444                        const char *show_doc,
 445                        const char *help_doc,
 446                        cmd_const_sfunc_ftype *set_func,
 447                        show_value_ftype *show_func,
 448                        struct cmd_list_element **set_list,
 449                        struct cmd_list_element **show_list);
 450
 451 extern void add_setshow_optional_filename_cmd (const char *name,
 452                                                enum command_class theclass,
 453                                                char **var,
 454                                                const char *set_doc,
 455                                                const char *show_doc,
 456                                                const char *help_doc,
 457                                                cmd_const_sfunc_ftype *set_func,
 458                                                show_value_ftype *show_func,
 459                                                struct cmd_list_element **set_list,
 460                                                struct cmd_list_element **show_list);
 461
 462 extern void add_setshow_integer_cmd (const char *name,
 463                                      enum command_class theclass,
 464                                      int *var,
 465                                      const char *set_doc,
 466                                      const char *show_doc,
 467                                      const char *help_doc,
 468                                      cmd_const_sfunc_ftype *set_func,
 469                                      show_value_ftype *show_func,
 470                                      struct cmd_list_element **set_list,
 471                                      struct cmd_list_element **show_list);
 472
 473 extern void add_setshow_uinteger_cmd (const char *name,
 474                                       enum command_class theclass,
 475                                       unsigned int *var,
 476                                       const char *set_doc,
 477                                       const char *show_doc,
 478                                       const char *help_doc,
 479                                       cmd_const_sfunc_ftype *set_func,
 480                                       show_value_ftype *show_func,
 481                                       struct cmd_list_element **set_list,
 482                                       struct cmd_list_element **show_list);
 483
 484 extern void add_setshow_zinteger_cmd (const char *name,
 485                                       enum command_class theclass,
 486                                       int *var,
 487                                       const char *set_doc,
 488                                       const char *show_doc,
 489                                       const char *help_doc,
 490                                       cmd_const_sfunc_ftype *set_func,
 491                                       show_value_ftype *show_func,
 492                                       struct cmd_list_element **set_list,
 493                                       struct cmd_list_element **show_list);
 494
 495 extern void add_setshow_zuinteger_cmd (const char *name,
 496                                        enum command_class theclass,
 497                                        unsigned int *var,
 498                                        const char *set_doc,
 499                                        const char *show_doc,
 500                                        const char *help_doc,
 501                                        cmd_const_sfunc_ftype *set_func,
 502                                        show_value_ftype *show_func,
 503                                        struct cmd_list_element **set_list,
 504                                        struct cmd_list_element **show_list);
 505
 506 extern void
 507   add_setshow_zuinteger_unlimited_cmd (const char *name,
 508                                        enum command_class theclass,
 509                                        int *var,
 510                                        const char *set_doc,
 511                                        const char *show_doc,
 512                                        const char *help_doc,
 513                                        cmd_const_sfunc_ftype *set_func,
 514                                        show_value_ftype *show_func,
 515                                        struct cmd_list_element **set_list,
 516                                        struct cmd_list_element **show_list);
 517
 518 /* Do a "show" command for each thing on a command list.  */
 519
 520 extern void cmd_show_list (struct cmd_list_element *, int);
 521
 522 /* Used everywhere whenever at least one parameter is required and
 523    none is specified.  */
 524
 525 extern void error_no_arg (const char *) ATTRIBUTE_NORETURN;
 526
 527
 528 /* Command line saving and repetition.
 529    Each input line executed is saved to possibly be repeated either
 530    when the user types an empty line, or be repeated by a command
 531    that wants to repeat the previously executed command.  The below
 532    functions control command repetition.  */
 533
 534 /* Commands call dont_repeat if they do not want to be repeated by null
 535    lines or by repeat_previous ().  */
 536
 537 extern void dont_repeat ();
 538
 539 /* Commands call repeat_previous if they want to repeat the previous
 540    command.  Such commands that repeat the previous command must
 541    indicate to not repeat themselves, to avoid recursive repeat.
 542    repeat_previous marks the current command as not repeating, and
 543    ensures get_saved_command_line returns the previous command, so
 544    that the currently executing command can repeat it.  If there's no
 545    previous command, throws an error.  Otherwise, returns the result
 546    of get_saved_command_line, which now points at the command to
 547    repeat.  */
 548
 549 extern const char *repeat_previous ();
 550
 551 /* Prevent dont_repeat from working, and return a cleanup that
 552    restores the previous state.  */
 553
 554 extern scoped_restore_tmpl<int> prevent_dont_repeat (void);
 555
 556 /* Set the arguments that will be passed if the current command is
 557    repeated.  Note that the passed-in string must be a constant.  */
 558
 559 extern void set_repeat_arguments (const char *args);
 560
 561 /* Returns the saved command line to repeat.
 562    When a command is being executed, this is the currently executing
 563    command line, unless the currently executing command has called
 564    repeat_previous (): in this case, get_saved_command_line returns
 565    the previously saved command line.  */
 566
 567 extern char *get_saved_command_line ();
 568
 569 /* Takes a copy of CMD, for possible repetition.  */
 570
 571 extern void save_command_line (const char *cmd);
 572
 573 /* Used to mark commands that don't do anything.  If we just leave the
 574    function field NULL, the command is interpreted as a help topic, or
 575    as a class of commands.  */
 576
 577 extern void not_just_help_class_command (const char *, int);
 578
 579 /* Check function pointer.  */
 580 extern int cmd_func_p (struct cmd_list_element *cmd);
 581
 582 /* Call the command function.  */
 583 extern void cmd_func (struct cmd_list_element *cmd,
 584                       const char *args, int from_tty);
 585
 586 #endif /* !defined (COMMAND_H) */