gdb/cli/cli-decode.h

   1 /* Header file for GDB command decoding library.
   2
   3    Copyright (C) 2000-2023 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 #ifndef CLI_CLI_DECODE_H
  19 #define CLI_CLI_DECODE_H
  20
  21 /* This file defines the private interfaces for any code implementing
  22    command internals.  */
  23
  24 /* Include the public interfaces.  */
  25 #include "command.h"
  26 #include "gdbsupport/gdb_regex.h"
  27 #include "cli-script.h"
  28 #include "completer.h"
  29 #include "gdbsupport/intrusive_list.h"
  30 #include "gdbsupport/buildargv.h"
  31
  32 /* Not a set/show command.  Note that some commands which begin with
  33    "set" or "show" might be in this category, if their syntax does
  34    not fall into one of the following categories.  */
  35 enum cmd_types
  36 {
  37   not_set_cmd,
  38   set_cmd,
  39   show_cmd
  40 };
  41
  42 /* This structure records one command'd definition.  */
  43
  44
  45 struct cmd_list_element
  46 {
  47   cmd_list_element (const char *name_, enum command_class theclass_,
  48                     const char *doc_)
  49     : name (name_),
  50       theclass (theclass_),
  51       cmd_deprecated (0),
  52       deprecated_warn_user (0),
  53       malloced_replacement (0),
  54       doc_allocated (0),
  55       name_allocated (0),
  56       hook_in (0),
  57       allow_unknown (0),
  58       abbrev_flag (0),
  59       type (not_set_cmd),
  60       doc (doc_)
  61   {
  62     memset (&function, 0, sizeof (function));
  63   }
  64
  65   ~cmd_list_element ()
  66   {
  67     if (doc && doc_allocated)
  68       xfree ((char *) doc);
  69     if (name_allocated)
  70       xfree ((char *) name);
  71   }
  72
  73   DISABLE_COPY_AND_ASSIGN (cmd_list_element);
  74
  75   /* For prefix commands, return a string containing prefix commands to
  76      get here: this one plus any others needed to get to it.  Ends in a
  77      space.  It is used before the word "command" in describing the
  78      commands reached through this prefix.
  79
  80      For non-prefix commands, return an empty string.  */
  81   std::string prefixname () const;
  82
  83   /* Return a vector of strings describing the components of the full name
  84      of this command.  For example, if this command is 'set AA BB CC',
  85      then the vector will contain 4 elements 'set', 'AA', 'BB', and 'CC'
  86      in that order.  */
  87   std::vector<std::string> command_components () const;
  88
  89   /* Return true if this command is an alias of another command.  */
  90   bool is_alias () const
  91   { return this->alias_target != nullptr; }
  92
  93   /* Return true if this command is a prefix command.  */
  94   bool is_prefix () const
  95   { return this->subcommands != nullptr; }
  96
  97   /* Return true if this command is a "command class help" command.  For
  98      instance, a "stack" dummy command is registered so that one can do
  99      "help stack" and show help for all commands of the "stack" class.  */
 100   bool is_command_class_help () const
 101   { return this->func == nullptr; }
 102
 103   void set_context (void *context)
 104   {
 105     gdb_assert (m_context == nullptr);
 106     m_context = context;
 107   }
 108
 109   void *context () const
 110   { return m_context; }
 111
 112   /* Points to next command in this list.  */
 113   struct cmd_list_element *next = nullptr;
 114
 115   /* Name of this command.  */
 116   const char *name;
 117
 118   /* Command class; class values are chosen by application program.  */
 119   enum command_class theclass;
 120
 121   /* When 1 indicated that this command is deprecated.  It may be
 122      removed from gdb's command set in the future.  */
 123
 124   unsigned int cmd_deprecated : 1;
 125
 126   /* The user needs to be warned that this is a deprecated command.
 127      The user should only be warned the first time a command is
 128      used.  */
 129
 130   unsigned int deprecated_warn_user : 1;
 131
 132   /* When functions are deprecated at compile time (this is the way
 133      it should, in general, be done) the memory containing the
 134      replacement string is statically allocated.  In some cases it
 135      makes sense to deprecate commands at runtime (the testsuite is
 136      one example).  In this case the memory for replacement is
 137      malloc'ed.  When a command is undeprecated or re-deprecated at
 138      runtime we don't want to risk calling free on statically
 139      allocated memory, so we check this flag.  */
 140
 141   unsigned int malloced_replacement : 1;
 142
 143   /* Set if the doc field should be xfree'd.  */
 144
 145   unsigned int doc_allocated : 1;
 146
 147   /* Set if the name field should be xfree'd.  */
 148
 149   unsigned int name_allocated : 1;
 150
 151   /* Flag that specifies if this command is already running its hook.  */
 152   /* Prevents the possibility of hook recursion.  */
 153   unsigned int hook_in : 1;
 154
 155   /* For prefix commands only:
 156      nonzero means do not get an error if subcommand is not
 157      recognized; call the prefix's own function in that case.  */
 158   unsigned int allow_unknown : 1;
 159
 160   /* Nonzero says this is an abbreviation, and should not
 161      be mentioned in lists of commands.
 162      This allows "br<tab>" to complete to "break", which it
 163      otherwise wouldn't.  */
 164   unsigned int abbrev_flag : 1;
 165
 166   /* Type of "set" or "show" command (or SET_NOT_SET if not "set"
 167      or "show").  */
 168   ENUM_BITFIELD (cmd_types) type : 2;
 169
 170   /* Function definition of this command.  NULL for command class
 171      names and for help topics that are not really commands.  NOTE:
 172      cagney/2002-02-02: This function signature is evolving.  For
 173      the moment suggest sticking with either set_cmd_cfunc() or
 174      set_cmd_sfunc().  */
 175   cmd_func_ftype *func;
 176
 177   /* The command's real callback.  At present func() bounces through
 178      to one of the below.  */
 179   union
 180     {
 181       /* Most commands don't need the cmd_list_element parameter passed to FUNC.
 182          They therefore register a command of this type, which doesn't have the
 183          cmd_list_element parameter.  do_simple_func is installed as FUNC, and
 184          acts as a shim between the two.  */
 185       cmd_simple_func_ftype *simple_func;
 186     }
 187   function;
 188
 189   /* Documentation of this command (or help topic).
 190      First line is brief documentation; remaining lines form, with it,
 191      the full documentation.  First line should end with a period.
 192      Entire string should also end with a period, not a newline.  */
 193   const char *doc;
 194
 195   /* For set/show commands.  A method for printing the output to the
 196      specified stream.  */
 197   show_value_ftype *show_value_func = nullptr;
 198
 199   /* If this command is deprecated, this is the replacement name.  */
 200   const char *replacement = nullptr;
 201
 202   /* Hook for another command to be executed before this command.  */
 203   struct cmd_list_element *hook_pre = nullptr;
 204
 205   /* Hook for another command to be executed after this command.  */
 206   struct cmd_list_element *hook_post = nullptr;
 207
 208   /* Default arguments to automatically prepend to the user
 209      provided arguments when running this command or alias.  */
 210   std::string default_args;
 211
 212   /* Nonzero identifies a prefix command.  For them, the address
 213      of the variable containing the list of subcommands.  */
 214   struct cmd_list_element **subcommands = nullptr;
 215
 216   /* The prefix command of this command.  */
 217   struct cmd_list_element *prefix = nullptr;
 218
 219   /* Completion routine for this command.  */
 220   completer_ftype *completer = symbol_completer;
 221
 222   /* Handle the word break characters for this completer.  Usually
 223      this function need not be defined, but for some types of
 224      completers (e.g., Python completers declared as methods inside
 225      a class) the word break chars may need to be redefined
 226      depending on the completer type (e.g., for filename
 227      completers).  */
 228   completer_handle_brkchars_ftype *completer_handle_brkchars = nullptr;
 229
 230   /* Destruction routine for this command.  If non-NULL, this is
 231      called when this command instance is destroyed.  This may be
 232      used to finalize the CONTEXT field, if needed.  */
 233   void (*destroyer) (struct cmd_list_element *self, void *context) = nullptr;
 234
 235   /* Setting affected by "set" and "show".  Not used if type is not_set_cmd.  */
 236   gdb::optional<setting> var;
 237
 238   /* Pointer to NULL terminated list of enumerated values (like
 239      argv).  */
 240   const char *const *enums = nullptr;
 241
 242   /* Pointer to command strings of user-defined commands */
 243   counted_command_line user_commands;
 244
 245   /* Pointer to command that is hooked by this one, (by hook_pre)
 246      so the hook can be removed when this one is deleted.  */
 247   struct cmd_list_element *hookee_pre = nullptr;
 248
 249   /* Pointer to command that is hooked by this one, (by hook_post)
 250      so the hook can be removed when this one is deleted.  */
 251   struct cmd_list_element *hookee_post = nullptr;
 252
 253   /* Pointer to command that is aliased by this one, so the
 254      aliased command can be located in case it has been hooked.  */
 255   struct cmd_list_element *alias_target = nullptr;
 256
 257   /* Node to link aliases on an alias list.  */
 258   using aliases_list_node_type
 259     = intrusive_list_node<cmd_list_element>;
 260   aliases_list_node_type aliases_list_node;
 261
 262   /* Linked list of all aliases of this command.  */
 263   using aliases_list_member_node_type
 264     = intrusive_member_node<cmd_list_element,
 265                             &cmd_list_element::aliases_list_node>;
 266   using aliases_list_type
 267     = intrusive_list<cmd_list_element, aliases_list_member_node_type>;
 268   aliases_list_type aliases;
 269
 270   /* If non-null, the pointer to a field in 'struct
 271      cli_suppress_notification', which will be set to true in cmd_func
 272      when this command is being executed.  It will be set back to false
 273      when the command has been executed.  */
 274   bool *suppress_notification = nullptr;
 275
 276 private:
 277   /* Local state (context) for this command.  This can be anything.  */
 278   void *m_context = nullptr;
 279 };
 280
 281 /* Functions that implement commands about CLI commands.  */
 282
 283 extern void help_cmd (const char *, struct ui_file *);
 284
 285 extern void apropos_cmd (struct ui_file *, struct cmd_list_element *,
 286                          bool verbose, compiled_regex &, const char *);
 287
 288 /* Used to mark commands that don't do anything.  If we just leave the
 289    function field NULL, the command is interpreted as a help topic, or
 290    as a class of commands.  */
 291
 292 extern void not_just_help_class_command (const char *arg, int from_tty);
 293
 294 /* Print only the first line of STR on STREAM.
 295    FOR_VALUE_PREFIX true indicates that the first line is output
 296    to be a prefix to show a value (see deprecated_show_value_hack):
 297    the first character is printed in uppercase, and the trailing
 298    dot character is not printed.  */
 299
 300 extern void print_doc_line (struct ui_file *stream, const char *str,
 301                             bool for_value_prefix);
 302
 303 /* The enums of boolean commands.  */
 304 extern const char * const boolean_enums[];
 305
 306 /* The enums of auto-boolean commands.  */
 307 extern const char * const auto_boolean_enums[];
 308
 309 /* Verify whether a given cmd_list_element is a user-defined command.
 310    Return 1 if it is user-defined.  Return 0 otherwise.  */
 311
 312 extern int cli_user_command_p (struct cmd_list_element *);
 313
 314 extern int find_command_name_length (const char *);
 315
 316 #endif /* CLI_CLI_DECODE_H */