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                                                 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    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    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 **subcommands,
 212                          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                                                        **, 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 /* Look up the command called NAME in the command list LIST.
 330
 331    Unlike LOOKUP_CMD, partial matches are ignored and only exact matches
 332    on NAME are considered.
 333
 334    LIST is a chain of struct cmd_list_element's.
 335
 336    If IGNORE_HELP_CLASSES is true (the default), ignore any command list
 337    elements which are actually help classes rather than commands (i.e.
 338    the function field of the struct cmd_list_element is null).
 339
 340    If found, return the struct cmd_list_element for that command,
 341    otherwise return NULLPTR.  */
 342
 343 extern struct cmd_list_element *lookup_cmd_exact
 344                         (const char *name,
 345                          struct cmd_list_element *list,
 346                          bool ignore_help_classes = true);
 347
 348 extern struct cmd_list_element *deprecate_cmd (struct cmd_list_element *,
 349                                                const char * );
 350
 351 extern void deprecated_cmd_warning (const char *, struct cmd_list_element *);
 352
 353 extern int lookup_cmd_composition (const char *text,
 354                                    struct cmd_list_element **alias,
 355                                    struct cmd_list_element **prefix_cmd,
 356                                    struct cmd_list_element **cmd);
 357
 358 extern struct cmd_list_element *add_com (const char *, enum command_class,
 359                                          cmd_const_cfunc_ftype *fun,
 360                                          const char *);
 361
 362 extern cmd_list_element *add_com_alias (const char *name,
 363                                         cmd_list_element *target,
 364                                         command_class theclass,
 365                                         int abbrev_flag);
 366
 367 extern struct cmd_list_element *add_com_suppress_notification
 368                        (const char *name, enum command_class theclass,
 369                         cmd_const_cfunc_ftype *fun, const char *doc,
 370                         int *supress_notification);
 371
 372 extern struct cmd_list_element *add_info (const char *,
 373                                           cmd_const_cfunc_ftype *fun,
 374                                           const char *);
 375
 376 extern struct cmd_list_element *add_info_alias (const char *, const char *,
 377                                                 int);
 378
 379 extern void complete_on_cmdlist (struct cmd_list_element *,
 380                                  completion_tracker &tracker,
 381                                  const char *, const char *, int);
 382
 383 extern void complete_on_enum (completion_tracker &tracker,
 384                               const char *const *enumlist,
 385                               const char *, const char *);
 386
 387 /* Functions that implement commands about CLI commands.  */
 388
 389 extern void help_list (struct cmd_list_element *, const char *,
 390                        enum command_class, struct ui_file *);
 391
 392 /* Method for show a set/show variable's VALUE on FILE.  If this
 393    method isn't supplied deprecated_show_value_hack() is called (which
 394    is not good).  */
 395 typedef void (show_value_ftype) (struct ui_file *file,
 396                                  int from_tty,
 397                                  struct cmd_list_element *cmd,
 398                                  const char *value);
 399 /* NOTE: i18n: This function is not i18n friendly.  Callers should
 400    instead print the value out directly.  */
 401 extern show_value_ftype deprecated_show_value_hack;
 402
 403 /* Return value type for the add_setshow_* functions.  */
 404
 405 struct set_show_commands
 406 {
 407   cmd_list_element *set, *show;
 408 };
 409
 410 extern set_show_commands add_setshow_enum_cmd
 411   (const char *name, command_class theclass, const char *const *enumlist,
 412    const char **var, const char *set_doc, const char *show_doc,
 413    const char *help_doc, cmd_const_sfunc_ftype *set_func,
 414    show_value_ftype *show_func, cmd_list_element **set_list,
 415    cmd_list_element **show_list, void *context = nullptr);
 416
 417 extern set_show_commands add_setshow_auto_boolean_cmd
 418   (const char *name, command_class theclass, auto_boolean *var,
 419    const char *set_doc, const char *show_doc, const char *help_doc,
 420    cmd_const_sfunc_ftype *set_func, show_value_ftype *show_func,
 421    cmd_list_element **set_list, cmd_list_element **show_list);
 422
 423 extern set_show_commands add_setshow_boolean_cmd
 424   (const char *name, command_class theclass, bool *var, const char *set_doc,
 425    const char *show_doc, const char *help_doc, cmd_const_sfunc_ftype *set_func,
 426    show_value_ftype *show_func, cmd_list_element **set_list,
 427    cmd_list_element **show_list);
 428
 429 extern set_show_commands add_setshow_filename_cmd
 430   (const char *name, command_class theclass, char **var, const char *set_doc,
 431    const char *show_doc, const char *help_doc, cmd_const_sfunc_ftype *set_func,
 432    show_value_ftype *show_func, cmd_list_element **set_list,
 433    cmd_list_element **show_list);
 434
 435 extern set_show_commands add_setshow_string_cmd
 436   (const char *name, command_class theclass, char **var, const char *set_doc,
 437    const char *show_doc, const char *help_doc, cmd_const_sfunc_ftype *set_func,
 438    show_value_ftype *show_func, cmd_list_element **set_list,
 439    cmd_list_element **show_list);
 440
 441 extern set_show_commands add_setshow_string_noescape_cmd
 442   (const char *name, command_class theclass, char **var, const char *set_doc,
 443    const char *show_doc, const char *help_doc, cmd_const_sfunc_ftype *set_func,
 444    show_value_ftype *show_func, cmd_list_element **set_list,
 445    cmd_list_element **show_list);
 446
 447 extern set_show_commands add_setshow_optional_filename_cmd
 448   (const char *name, command_class theclass, char **var, const char *set_doc,
 449    const char *show_doc, const char *help_doc, cmd_const_sfunc_ftype *set_func,
 450    show_value_ftype *show_func, cmd_list_element **set_list,
 451    cmd_list_element **show_list);
 452
 453 extern set_show_commands add_setshow_integer_cmd
 454   (const char *name, command_class theclass, int *var, const char *set_doc,
 455    const char *show_doc, const char *help_doc, cmd_const_sfunc_ftype *set_func,
 456    show_value_ftype *show_func, cmd_list_element **set_list,
 457    cmd_list_element **show_list);
 458
 459 extern set_show_commands add_setshow_uinteger_cmd
 460   (const char *name, command_class theclass, unsigned int *var,
 461    const char *set_doc, const char *show_doc, const char *help_doc,
 462    cmd_const_sfunc_ftype *set_func, show_value_ftype *show_func,
 463    cmd_list_element **set_list, cmd_list_element **show_list);
 464
 465 extern set_show_commands add_setshow_zinteger_cmd
 466   (const char *name, command_class theclass, int *var, const char *set_doc,
 467    const char *show_doc, const char *help_doc, cmd_const_sfunc_ftype *set_func,
 468    show_value_ftype *show_func, cmd_list_element **set_list,
 469    cmd_list_element **show_list);
 470
 471 extern set_show_commands add_setshow_zuinteger_cmd
 472   (const char *name, command_class theclass, unsigned int *var,
 473    const char *set_doc, const char *show_doc, const char *help_doc,
 474    cmd_const_sfunc_ftype *set_func, show_value_ftype *show_func,
 475    cmd_list_element **set_list, cmd_list_element **show_list);
 476
 477 extern set_show_commands add_setshow_zuinteger_unlimited_cmd
 478   (const char *name, command_class theclass, int *var, const char *set_doc,
 479    const char *show_doc, const char *help_doc, cmd_const_sfunc_ftype *set_func,
 480    show_value_ftype *show_func, cmd_list_element **set_list,
 481    cmd_list_element **show_list);
 482
 483 /* Do a "show" command for each thing on a command list.  */
 484
 485 extern void cmd_show_list (struct cmd_list_element *, int);
 486
 487 /* Used everywhere whenever at least one parameter is required and
 488    none is specified.  */
 489
 490 extern void error_no_arg (const char *) ATTRIBUTE_NORETURN;
 491
 492
 493 /* Command line saving and repetition.
 494    Each input line executed is saved to possibly be repeated either
 495    when the user types an empty line, or be repeated by a command
 496    that wants to repeat the previously executed command.  The below
 497    functions control command repetition.  */
 498
 499 /* Commands call dont_repeat if they do not want to be repeated by null
 500    lines or by repeat_previous ().  */
 501
 502 extern void dont_repeat ();
 503
 504 /* Commands call repeat_previous if they want to repeat the previous
 505    command.  Such commands that repeat the previous command must
 506    indicate to not repeat themselves, to avoid recursive repeat.
 507    repeat_previous marks the current command as not repeating, and
 508    ensures get_saved_command_line returns the previous command, so
 509    that the currently executing command can repeat it.  If there's no
 510    previous command, throws an error.  Otherwise, returns the result
 511    of get_saved_command_line, which now points at the command to
 512    repeat.  */
 513
 514 extern const char *repeat_previous ();
 515
 516 /* Prevent dont_repeat from working, and return a cleanup that
 517    restores the previous state.  */
 518
 519 extern scoped_restore_tmpl<int> prevent_dont_repeat (void);
 520
 521 /* Set the arguments that will be passed if the current command is
 522    repeated.  Note that the passed-in string must be a constant.  */
 523
 524 extern void set_repeat_arguments (const char *args);
 525
 526 /* Returns the saved command line to repeat.
 527    When a command is being executed, this is the currently executing
 528    command line, unless the currently executing command has called
 529    repeat_previous (): in this case, get_saved_command_line returns
 530    the previously saved command line.  */
 531
 532 extern char *get_saved_command_line ();
 533
 534 /* Takes a copy of CMD, for possible repetition.  */
 535
 536 extern void save_command_line (const char *cmd);
 537
 538 /* Used to mark commands that don't do anything.  If we just leave the
 539    function field NULL, the command is interpreted as a help topic, or
 540    as a class of commands.  */
 541
 542 extern void not_just_help_class_command (const char *, int);
 543
 544 /* Call the command function.  */
 545 extern void cmd_func (struct cmd_list_element *cmd,
 546                       const char *args, int from_tty);
 547
 548 #endif /* !defined (COMMAND_H) */