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 /* The "simple" signature of command callbacks, which doesn't include a
 132    cmd_list_element parameter.  */
 133
 134 typedef void cmd_simple_func_ftype (const char *args, int from_tty);
 135
 136 /* This structure specifies notifications to be suppressed by a cli
 137    command interpreter.  */
 138
 139 struct cli_suppress_notification
 140 {
 141   /* Inferior, thread, frame selected notification suppressed?  */
 142   int user_selected_context;
 143 };
 144
 145 extern struct cli_suppress_notification cli_suppress_notification;
 146
 147 /* Forward-declarations of the entry-points of cli/cli-decode.c.  */
 148
 149 /* API to the manipulation of command lists.  */
 150
 151 /* Return TRUE if NAME is a valid user-defined command name.
 152    This is a stricter subset of all gdb commands,
 153    see find_command_name_length.  */
 154
 155 extern bool valid_user_defined_cmd_name_p (const char *name);
 156
 157 /* Return TRUE if C is a valid command character.  */
 158
 159 extern bool valid_cmd_char_p (int c);
 160
 161 /* Const-correct variant of the above.  */
 162
 163 extern struct cmd_list_element *add_cmd (const char *, enum command_class,
 164                                          cmd_simple_func_ftype *fun,
 165                                          const char *,
 166                                          struct cmd_list_element **);
 167
 168 /* Like add_cmd, but no command function is specified.  */
 169
 170 extern struct cmd_list_element *add_cmd (const char *, enum command_class,
 171                                          const char *,
 172                                          struct cmd_list_element **);
 173
 174 extern struct cmd_list_element *add_cmd_suppress_notification
 175                         (const char *name, enum command_class theclass,
 176                          cmd_simple_func_ftype *fun, const char *doc,
 177                          struct cmd_list_element **list,
 178                          int *suppress_notification);
 179
 180 extern struct cmd_list_element *add_alias_cmd (const char *,
 181                                                cmd_list_element *,
 182                                                enum command_class, int,
 183                                                struct cmd_list_element **);
 184
 185
 186 extern struct cmd_list_element *add_prefix_cmd (const char *, enum command_class,
 187                                                 cmd_simple_func_ftype *fun,
 188                                                 const char *,
 189                                                 struct cmd_list_element **,
 190                                                 int,
 191                                                 struct cmd_list_element **);
 192
 193 /* Like add_prefix_cmd, but sets the callback to a function that
 194    simply calls help_list.  */
 195
 196 extern struct cmd_list_element *add_basic_prefix_cmd
 197   (const char *, enum command_class, const char *, struct cmd_list_element **,
 198    int, struct cmd_list_element **);
 199
 200 /* Like add_prefix_cmd, but useful for "show" prefixes.  This sets the
 201    callback to a function that simply calls cmd_show_list.  */
 202
 203 extern struct cmd_list_element *add_show_prefix_cmd
 204   (const char *, enum command_class, const char *, struct cmd_list_element **,
 205    int, struct cmd_list_element **);
 206
 207 extern struct cmd_list_element *add_prefix_cmd_suppress_notification
 208                         (const char *name, enum command_class theclass,
 209                          cmd_simple_func_ftype *fun,
 210                          const char *doc, struct cmd_list_element **subcommands,
 211                          int allow_unknown,
 212                          struct cmd_list_element **list,
 213                          int *suppress_notification);
 214
 215 extern struct cmd_list_element *add_abbrev_prefix_cmd (const char *,
 216                                                        enum command_class,
 217                                                        cmd_simple_func_ftype *fun,
 218                                                        const char *,
 219                                                        struct cmd_list_element
 220                                                        **, int,
 221                                                        struct cmd_list_element
 222                                                        **);
 223
 224 typedef void cmd_func_ftype (const char *args, int from_tty,
 225                              cmd_list_element *c);
 226
 227 /* A completion routine.  Add possible completions to tracker.
 228
 229    TEXT is the text beyond what was matched for the command itself
 230    (leading whitespace is skipped).  It stops where we are supposed to
 231    stop completing (rl_point) and is '\0' terminated.  WORD points in
 232    the same buffer as TEXT, and completions should be returned
 233    relative to this position.  For example, suppose TEXT is "foo" and
 234    we want to complete to "foobar".  If WORD is "oo", return "oobar";
 235    if WORD is "baz/foo", return "baz/foobar".  */
 236 typedef void completer_ftype (struct cmd_list_element *,
 237                               completion_tracker &tracker,
 238                               const char *text, const char *word);
 239
 240 /* Same, but for set_cmd_completer_handle_brkchars.  */
 241 typedef void completer_handle_brkchars_ftype (struct cmd_list_element *,
 242                                               completion_tracker &tracker,
 243                                               const char *text, const char *word);
 244
 245 extern void set_cmd_completer (struct cmd_list_element *, completer_ftype *);
 246
 247 /* Set the completer_handle_brkchars callback.  */
 248
 249 extern void set_cmd_completer_handle_brkchars (struct cmd_list_element *,
 250                                                completer_handle_brkchars_ftype *);
 251
 252 /* HACK: cagney/2002-02-23: Code, mostly in tracepoints.c, grubs
 253    around in cmd objects to test the value of the commands sfunc().  */
 254 extern int cmd_simple_func_eq (struct cmd_list_element *cmd,
 255                          cmd_simple_func_ftype *cfun);
 256
 257 /* Execute CMD's pre/post hook.  Throw an error if the command fails.
 258    If already executing this pre/post hook, or there is no pre/post
 259    hook, the call is silently ignored.  */
 260 extern void execute_cmd_pre_hook (struct cmd_list_element *cmd);
 261 extern void execute_cmd_post_hook (struct cmd_list_element *cmd);
 262
 263 /* Flag for an ambiguous cmd_list result.  */
 264 #define CMD_LIST_AMBIGUOUS ((struct cmd_list_element *) -1)
 265
 266 extern struct cmd_list_element *lookup_cmd (const char **,
 267                                             struct cmd_list_element *,
 268                                             const char *,
 269                                             std::string *,
 270                                             int, int);
 271
 272 /* This routine takes a line of TEXT and a CLIST in which to start the
 273    lookup.  When it returns it will have incremented the text pointer past
 274    the section of text it matched, set *RESULT_LIST to point to the list in
 275    which the last word was matched, and will return a pointer to the cmd
 276    list element which the text matches.  It will return NULL if no match at
 277    all was possible.  It will return -1 (cast appropriately, ick) if ambigous
 278    matches are possible; in this case *RESULT_LIST will be set to point to
 279    the list in which there are ambiguous choices (and *TEXT will be set to
 280    the ambiguous text string).
 281
 282    if DEFAULT_ARGS is not null, *DEFAULT_ARGS is set to the found command
 283    default args (possibly empty).
 284
 285    If the located command was an abbreviation, this routine returns the base
 286    command of the abbreviation.  Note that *DEFAULT_ARGS will contain the
 287    default args defined for the alias.
 288
 289    It does no error reporting whatsoever; control will always return
 290    to the superior routine.
 291
 292    In the case of an ambiguous return (-1), *RESULT_LIST will be set to point
 293    at the prefix_command (ie. the best match) *or* (special case) will be NULL
 294    if no prefix command was ever found.  For example, in the case of "info a",
 295    "info" matches without ambiguity, but "a" could be "args" or "address", so
 296    *RESULT_LIST is set to the cmd_list_element for "info".  So in this case
 297    RESULT_LIST should not be interpreted as a pointer to the beginning of a
 298    list; it simply points to a specific command.  In the case of an ambiguous
 299    return *TEXT is advanced past the last non-ambiguous prefix (e.g.
 300    "info t" can be "info types" or "info target"; upon return *TEXT has been
 301    advanced past "info ").
 302
 303    If RESULT_LIST is NULL, don't set *RESULT_LIST (but don't otherwise
 304    affect the operation).
 305
 306    This routine does *not* modify the text pointed to by TEXT.
 307
 308    If IGNORE_HELP_CLASSES is nonzero, ignore any command list elements which
 309    are actually help classes rather than commands (i.e. the function field of
 310    the struct cmd_list_element is NULL).
 311
 312    When LOOKUP_FOR_COMPLETION_P is true the completion is being requested
 313    for the completion engine, no warnings should be printed.  */
 314
 315 extern struct cmd_list_element *lookup_cmd_1
 316         (const char **text, struct cmd_list_element *clist,
 317          struct cmd_list_element **result_list, std::string *default_args,
 318          int ignore_help_classes, bool lookup_for_completion_p = false);
 319
 320 /* Look up the command called NAME in the command list LIST.
 321
 322    Unlike LOOKUP_CMD, partial matches are ignored and only exact matches
 323    on NAME are considered.
 324
 325    LIST is a chain of struct cmd_list_element's.
 326
 327    If IGNORE_HELP_CLASSES is true (the default), ignore any command list
 328    elements which are actually help classes rather than commands (i.e.
 329    the function field of the struct cmd_list_element is null).
 330
 331    If found, return the struct cmd_list_element for that command,
 332    otherwise return NULLPTR.  */
 333
 334 extern struct cmd_list_element *lookup_cmd_exact
 335                         (const char *name,
 336                          struct cmd_list_element *list,
 337                          bool ignore_help_classes = true);
 338
 339 extern struct cmd_list_element *deprecate_cmd (struct cmd_list_element *,
 340                                                const char * );
 341
 342 extern void deprecated_cmd_warning (const char *, struct cmd_list_element *);
 343
 344 extern int lookup_cmd_composition (const char *text,
 345                                    struct cmd_list_element **alias,
 346                                    struct cmd_list_element **prefix_cmd,
 347                                    struct cmd_list_element **cmd);
 348
 349 extern struct cmd_list_element *add_com (const char *, enum command_class,
 350                                          cmd_simple_func_ftype *fun,
 351                                          const char *);
 352
 353 extern cmd_list_element *add_com_alias (const char *name,
 354                                         cmd_list_element *target,
 355                                         command_class theclass,
 356                                         int abbrev_flag);
 357
 358 extern struct cmd_list_element *add_com_suppress_notification
 359                        (const char *name, enum command_class theclass,
 360                         cmd_simple_func_ftype *fun, const char *doc,
 361                         int *supress_notification);
 362
 363 extern struct cmd_list_element *add_info (const char *,
 364                                           cmd_simple_func_ftype *fun,
 365                                           const char *);
 366
 367 extern cmd_list_element *add_info_alias (const char *name,
 368                                          cmd_list_element *target,
 369                                          int abbrev_flag);
 370
 371 extern void complete_on_cmdlist (struct cmd_list_element *,
 372                                  completion_tracker &tracker,
 373                                  const char *, const char *, int);
 374
 375 extern void complete_on_enum (completion_tracker &tracker,
 376                               const char *const *enumlist,
 377                               const char *, const char *);
 378
 379 /* Functions that implement commands about CLI commands.  */
 380
 381 extern void help_list (struct cmd_list_element *, const char *,
 382                        enum command_class, struct ui_file *);
 383
 384 /* Method for show a set/show variable's VALUE on FILE.  If this
 385    method isn't supplied deprecated_show_value_hack() is called (which
 386    is not good).  */
 387 typedef void (show_value_ftype) (struct ui_file *file,
 388                                  int from_tty,
 389                                  struct cmd_list_element *cmd,
 390                                  const char *value);
 391 /* NOTE: i18n: This function is not i18n friendly.  Callers should
 392    instead print the value out directly.  */
 393 extern show_value_ftype deprecated_show_value_hack;
 394
 395 /* Return value type for the add_setshow_* functions.  */
 396
 397 struct set_show_commands
 398 {
 399   cmd_list_element *set, *show;
 400 };
 401
 402 extern set_show_commands add_setshow_enum_cmd
 403   (const char *name, command_class theclass, const char *const *enumlist,
 404    const char **var, const char *set_doc, const char *show_doc,
 405    const char *help_doc, cmd_func_ftype *set_func,
 406    show_value_ftype *show_func, cmd_list_element **set_list,
 407    cmd_list_element **show_list);
 408
 409 extern set_show_commands add_setshow_auto_boolean_cmd
 410   (const char *name, command_class theclass, auto_boolean *var,
 411    const char *set_doc, const char *show_doc, const char *help_doc,
 412    cmd_func_ftype *set_func, show_value_ftype *show_func,
 413    cmd_list_element **set_list, cmd_list_element **show_list);
 414
 415 extern set_show_commands add_setshow_boolean_cmd
 416   (const char *name, command_class theclass, bool *var, const char *set_doc,
 417    const char *show_doc, const char *help_doc, cmd_func_ftype *set_func,
 418    show_value_ftype *show_func, cmd_list_element **set_list,
 419    cmd_list_element **show_list);
 420
 421 extern set_show_commands add_setshow_filename_cmd
 422   (const char *name, command_class theclass, char **var, const char *set_doc,
 423    const char *show_doc, const char *help_doc, cmd_func_ftype *set_func,
 424    show_value_ftype *show_func, cmd_list_element **set_list,
 425    cmd_list_element **show_list);
 426
 427 extern set_show_commands add_setshow_string_cmd
 428   (const char *name, command_class theclass, char **var, const char *set_doc,
 429    const char *show_doc, const char *help_doc, cmd_func_ftype *set_func,
 430    show_value_ftype *show_func, cmd_list_element **set_list,
 431    cmd_list_element **show_list);
 432
 433 extern set_show_commands add_setshow_string_noescape_cmd
 434   (const char *name, command_class theclass, char **var, const char *set_doc,
 435    const char *show_doc, const char *help_doc, cmd_func_ftype *set_func,
 436    show_value_ftype *show_func, cmd_list_element **set_list,
 437    cmd_list_element **show_list);
 438
 439 extern set_show_commands add_setshow_optional_filename_cmd
 440   (const char *name, command_class theclass, char **var, const char *set_doc,
 441    const char *show_doc, const char *help_doc, cmd_func_ftype *set_func,
 442    show_value_ftype *show_func, cmd_list_element **set_list,
 443    cmd_list_element **show_list);
 444
 445 extern set_show_commands add_setshow_integer_cmd
 446   (const char *name, command_class theclass, int *var, const char *set_doc,
 447    const char *show_doc, const char *help_doc, cmd_func_ftype *set_func,
 448    show_value_ftype *show_func, cmd_list_element **set_list,
 449    cmd_list_element **show_list);
 450
 451 extern set_show_commands add_setshow_uinteger_cmd
 452   (const char *name, command_class theclass, unsigned int *var,
 453    const char *set_doc, const char *show_doc, const char *help_doc,
 454    cmd_func_ftype *set_func, show_value_ftype *show_func,
 455    cmd_list_element **set_list, cmd_list_element **show_list);
 456
 457 extern set_show_commands add_setshow_zinteger_cmd
 458   (const char *name, command_class theclass, int *var, const char *set_doc,
 459    const char *show_doc, const char *help_doc, cmd_func_ftype *set_func,
 460    show_value_ftype *show_func, cmd_list_element **set_list,
 461    cmd_list_element **show_list);
 462
 463 extern set_show_commands add_setshow_zuinteger_cmd
 464   (const char *name, command_class theclass, unsigned int *var,
 465    const char *set_doc, const char *show_doc, const char *help_doc,
 466    cmd_func_ftype *set_func, show_value_ftype *show_func,
 467    cmd_list_element **set_list, cmd_list_element **show_list);
 468
 469 extern set_show_commands add_setshow_zuinteger_unlimited_cmd
 470   (const char *name, command_class theclass, int *var, const char *set_doc,
 471    const char *show_doc, const char *help_doc, cmd_func_ftype *set_func,
 472    show_value_ftype *show_func, cmd_list_element **set_list,
 473    cmd_list_element **show_list);
 474
 475 /* Do a "show" command for each thing on a command list.  */
 476
 477 extern void cmd_show_list (struct cmd_list_element *, int);
 478
 479 /* Used everywhere whenever at least one parameter is required and
 480    none is specified.  */
 481
 482 extern void error_no_arg (const char *) ATTRIBUTE_NORETURN;
 483
 484
 485 /* Command line saving and repetition.
 486    Each input line executed is saved to possibly be repeated either
 487    when the user types an empty line, or be repeated by a command
 488    that wants to repeat the previously executed command.  The below
 489    functions control command repetition.  */
 490
 491 /* Commands call dont_repeat if they do not want to be repeated by null
 492    lines or by repeat_previous ().  */
 493
 494 extern void dont_repeat ();
 495
 496 /* Commands call repeat_previous if they want to repeat the previous
 497    command.  Such commands that repeat the previous command must
 498    indicate to not repeat themselves, to avoid recursive repeat.
 499    repeat_previous marks the current command as not repeating, and
 500    ensures get_saved_command_line returns the previous command, so
 501    that the currently executing command can repeat it.  If there's no
 502    previous command, throws an error.  Otherwise, returns the result
 503    of get_saved_command_line, which now points at the command to
 504    repeat.  */
 505
 506 extern const char *repeat_previous ();
 507
 508 /* Prevent dont_repeat from working, and return a cleanup that
 509    restores the previous state.  */
 510
 511 extern scoped_restore_tmpl<int> prevent_dont_repeat (void);
 512
 513 /* Set the arguments that will be passed if the current command is
 514    repeated.  Note that the passed-in string must be a constant.  */
 515
 516 extern void set_repeat_arguments (const char *args);
 517
 518 /* Returns the saved command line to repeat.
 519    When a command is being executed, this is the currently executing
 520    command line, unless the currently executing command has called
 521    repeat_previous (): in this case, get_saved_command_line returns
 522    the previously saved command line.  */
 523
 524 extern char *get_saved_command_line ();
 525
 526 /* Takes a copy of CMD, for possible repetition.  */
 527
 528 extern void save_command_line (const char *cmd);
 529
 530 /* Used to mark commands that don't do anything.  If we just leave the
 531    function field NULL, the command is interpreted as a help topic, or
 532    as a class of commands.  */
 533
 534 extern void not_just_help_class_command (const char *, int);
 535
 536 /* Call the command function.  */
 537 extern void cmd_func (struct cmd_list_element *cmd,
 538                       const char *args, int from_tty);
 539
 540 #endif /* !defined (COMMAND_H) */