gdb/cli/cli-option.c

   1 /* CLI options framework, for GDB.
   2
   3    Copyright (C) 2017-2019 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "cli/cli-option.h"
  22 #include "cli/cli-decode.h"
  23 #include "cli/cli-utils.h"
  24 #include "cli/cli-setshow.h"
  25 #include "command.h"
  26 #include <vector>
  27
  28 namespace gdb {
  29 namespace option {
  30
  31 /* An option's value.  Which field is active depends on the option's
  32    type.  */
  33 union option_value
  34 {
  35   /* For var_boolean options.  */
  36   bool boolean;
  37
  38   /* For var_uinteger options.  */
  39   unsigned int uinteger;
  40
  41   /* For var_zuinteger_unlimited options.  */
  42   int integer;
  43
  44   /* For var_enum options.  */
  45   const char *enumeration;
  46
  47   /* For var_string options.  This is malloc-allocated.  */
  48   char *string;
  49 };
  50
  51 /* Holds an options definition and its value.  */
  52 struct option_def_and_value
  53 {
  54   /* The option definition.  */
  55   const option_def &option;
  56
  57   /* A context.  */
  58   void *ctx;
  59
  60   /* The option's value, if any.  */
  61   gdb::optional<option_value> value;
  62
  63   /* Constructor.  */
  64   option_def_and_value (const option_def &option_, void *ctx_,
  65                         gdb::optional<option_value> &&value_ = {})
  66     : option (option_),
  67       ctx (ctx_),
  68       value (std::move (value_))
  69   {
  70     clear_value (option_, value_);
  71   }
  72
  73   /* Move constructor.  Need this because for some types the values
  74      are allocated on the heap.  */
  75   option_def_and_value (option_def_and_value &&rval)
  76     : option (rval.option),
  77       ctx (rval.ctx),
  78       value (std::move (rval.value))
  79   {
  80     clear_value (rval.option, rval.value);
  81   }
  82
  83   DISABLE_COPY_AND_ASSIGN (option_def_and_value);
  84
  85   ~option_def_and_value ()
  86   {
  87     if (value.has_value ())
  88       {
  89         if (option.type == var_string)
  90           xfree (value->string);
  91       }
  92   }
  93
  94 private:
  95
  96   /* Clear the option_value, without releasing it.  This is used after
  97      the value has been moved to some other option_def_and_value
  98      instance.  This is needed because for some types the value is
  99      allocated on the heap, so we must clear the pointer in the
 100      source, to avoid a double free.  */
 101   static void clear_value (const option_def &option,
 102                            gdb::optional<option_value> &value)
 103   {
 104     if (value.has_value ())
 105       {
 106         if (option.type == var_string)
 107           value->string = nullptr;
 108       }
 109   }
 110 };
 111
 112 static void save_option_value_in_ctx (gdb::optional<option_def_and_value> &ov);
 113
 114 /* Info passed around when handling completion.  */
 115 struct parse_option_completion_info
 116 {
 117   /* The completion word.  */
 118   const char *word;
 119
 120   /* The tracker.  */
 121   completion_tracker &tracker;
 122 };
 123
 124 /* If ARGS starts with "-", look for a "--" delimiter.  If one is
 125    found, then interpret everything up until the "--" as command line
 126    options.  Otherwise, interpret unknown input as the beginning of
 127    the command's operands.  */
 128
 129 static const char *
 130 find_end_options_delimiter (const char *args)
 131 {
 132   if (args[0] == '-')
 133     {
 134       const char *p = args;
 135
 136       p = skip_spaces (p);
 137       while (*p)
 138         {
 139           if (check_for_argument (&p, "--"))
 140             return p;
 141           else
 142             p = skip_to_space (p);
 143           p = skip_spaces (p);
 144         }
 145     }
 146
 147   return nullptr;
 148 }
 149
 150 /* Complete TEXT/WORD on all options in OPTIONS_GROUP.  */
 151
 152 static void
 153 complete_on_options (gdb::array_view<const option_def_group> options_group,
 154                      completion_tracker &tracker,
 155                      const char *text, const char *word)
 156 {
 157   size_t textlen = strlen (text);
 158   for (const auto &grp : options_group)
 159     for (const auto &opt : grp.options)
 160       if (strncmp (opt.name, text, textlen) == 0)
 161         {
 162           tracker.add_completion
 163             (make_completion_match_str (opt.name, text, word));
 164         }
 165 }
 166
 167 /* See cli-option.h.  */
 168
 169 void
 170 complete_on_all_options (completion_tracker &tracker,
 171                          gdb::array_view<const option_def_group> options_group)
 172 {
 173   static const char opt[] = "-";
 174   complete_on_options (options_group, tracker, opt + 1, opt);
 175 }
 176
 177 /* Parse ARGS, guided by OPTIONS_GROUP.  HAVE_DELIMITER is true if the
 178    whole ARGS line included the "--" options-terminator delimiter.  */
 179
 180 static gdb::optional<option_def_and_value>
 181 parse_option (gdb::array_view<const option_def_group> options_group,
 182               process_options_mode mode,
 183               bool have_delimiter,
 184               const char **args,
 185               parse_option_completion_info *completion = nullptr)
 186 {
 187   if (*args == nullptr)
 188     return {};
 189   else if (**args != '-')
 190     {
 191       if (have_delimiter)
 192         error (_("Unrecognized option at: %s"), *args);
 193       return {};
 194     }
 195   else if (check_for_argument (args, "--"))
 196     return {};
 197
 198   /* Skip the initial '-'.  */
 199   const char *arg = *args + 1;
 200
 201   const char *after = skip_to_space (arg);
 202   size_t len = after - arg;
 203   const option_def *match = nullptr;
 204   void *match_ctx = nullptr;
 205
 206   for (const auto &grp : options_group)
 207     {
 208       for (const auto &o : grp.options)
 209         {
 210           if (strncmp (o.name, arg, len) == 0)
 211             {
 212               if (match != nullptr)
 213                 {
 214                   if (completion != nullptr && arg[len] == '\0')
 215                     {
 216                       complete_on_options (options_group,
 217                                            completion->tracker,
 218                                            arg, completion->word);
 219                       return {};
 220                     }
 221
 222                   error (_("Ambiguous option at: -%s"), arg);
 223                 }
 224
 225               match = &o;
 226               match_ctx = grp.ctx;
 227
 228               if ((isspace (arg[len]) || arg[len] == '\0')
 229                   && strlen (o.name) == len)
 230                 break; /* Exact match.  */
 231             }
 232         }
 233     }
 234
 235   if (match == nullptr)
 236     {
 237       if (have_delimiter || mode != PROCESS_OPTIONS_UNKNOWN_IS_OPERAND)
 238         error (_("Unrecognized option at: %s"), *args);
 239
 240       return {};
 241     }
 242
 243   if (completion != nullptr && arg[len] == '\0')
 244     {
 245       complete_on_options (options_group, completion->tracker,
 246                            arg, completion->word);
 247       return {};
 248     }
 249
 250   *args += 1 + len;
 251   *args = skip_spaces (*args);
 252   if (completion != nullptr)
 253     completion->word = *args;
 254
 255   switch (match->type)
 256     {
 257     case var_boolean:
 258       {
 259         if (!match->have_argument)
 260           {
 261             option_value val;
 262             val.boolean = true;
 263             return option_def_and_value {*match, match_ctx, val};
 264           }
 265
 266         const char *val_str = *args;
 267         int res;
 268
 269         if (**args == '\0' && completion != nullptr)
 270           {
 271             /* Complete on both "on/off" and more options.  */
 272
 273             if (mode == PROCESS_OPTIONS_REQUIRE_DELIMITER)
 274               {
 275                 complete_on_enum (completion->tracker,
 276                                   boolean_enums, val_str, val_str);
 277                 complete_on_all_options (completion->tracker, options_group);
 278               }
 279             return option_def_and_value {*match, match_ctx};
 280           }
 281         else if (**args == '-')
 282           {
 283             /* Treat:
 284                  "cmd -boolean-option -another-opt..."
 285                as:
 286                  "cmd -boolean-option on -another-opt..."
 287              */
 288             res = 1;
 289           }
 290         else if (**args == '\0')
 291           {
 292             /* Treat:
 293                  (1) "cmd -boolean-option "
 294                as:
 295                  (1) "cmd -boolean-option on"
 296              */
 297             res = 1;
 298           }
 299         else
 300           {
 301             res = parse_cli_boolean_value (args);
 302             if (res < 0)
 303               {
 304                 const char *end = skip_to_space (*args);
 305                 if (completion != nullptr)
 306                   {
 307                     if (*end == '\0')
 308                       {
 309                         complete_on_enum (completion->tracker,
 310                                           boolean_enums, val_str, val_str);
 311                         return option_def_and_value {*match, match_ctx};
 312                       }
 313                   }
 314
 315                 if (have_delimiter)
 316                   error (_("Value given for `-%s' is not a boolean: %.*s"),
 317                          match->name, (int) (end - val_str), val_str);
 318                 /* The user didn't separate options from operands
 319                    using "--", so treat this unrecognized value as the
 320                    start of the operands.  This makes "frame apply all
 321                    -past-main CMD" work.  */
 322                 return option_def_and_value {*match, match_ctx};
 323               }
 324             else if (completion != nullptr && **args == '\0')
 325               {
 326                 /* While "cmd -boolean [TAB]" only offers "on" and
 327                    "off", the boolean option actually accepts "1",
 328                    "yes", etc. as boolean values.  We complete on all
 329                    of those instead of BOOLEAN_ENUMS here to make
 330                    these work:
 331
 332                     "p -object 1[TAB]" -> "p -object 1 "
 333                     "p -object ye[TAB]" -> "p -object yes "
 334
 335                    Etc.  Note that it's important that the space is
 336                    auto-appended.  Otherwise, if we only completed on
 337                    on/off here, then it might look to the user like
 338                    "1" isn't valid, like:
 339                    "p -object 1[TAB]" -> "p -object 1" (i.e., nothing happens).
 340                 */
 341                 static const char *const all_boolean_enums[] = {
 342                   "on", "off",
 343                   "yes", "no",
 344                   "enable", "disable",
 345                   "0", "1",
 346                   nullptr,
 347                 };
 348                 complete_on_enum (completion->tracker, all_boolean_enums,
 349                                   val_str, val_str);
 350                 return {};
 351               }
 352           }
 353
 354         option_value val;
 355         val.boolean = res;
 356         return option_def_and_value {*match, match_ctx, val};
 357       }
 358     case var_uinteger:
 359     case var_zuinteger_unlimited:
 360       {
 361         if (completion != nullptr)
 362           {
 363             if (**args == '\0')
 364               {
 365                 /* Convenience to let the user know what the option
 366                    can accept.  Note there's no common prefix between
 367                    the strings on purpose, so that readline doesn't do
 368                    a partial match.  */
 369                 completion->tracker.add_completion
 370                   (make_unique_xstrdup ("NUMBER"));
 371                 completion->tracker.add_completion
 372                   (make_unique_xstrdup ("unlimited"));
 373                 return {};
 374               }
 375             else if (startswith ("unlimited", *args))
 376               {
 377                 completion->tracker.add_completion
 378                   (make_unique_xstrdup ("unlimited"));
 379                 return {};
 380               }
 381           }
 382
 383         if (match->type == var_zuinteger_unlimited)
 384           {
 385             option_value val;
 386             val.integer = parse_cli_var_zuinteger_unlimited (args, false);
 387             return option_def_and_value {*match, match_ctx, val};
 388           }
 389         else
 390           {
 391             option_value val;
 392             val.uinteger = parse_cli_var_uinteger (match->type, args, false);
 393             return option_def_and_value {*match, match_ctx, val};
 394           }
 395       }
 396     case var_enum:
 397       {
 398         if (completion != nullptr)
 399           {
 400             const char *after_arg = skip_to_space (*args);
 401             if (*after_arg == '\0')
 402               {
 403                 complete_on_enum (completion->tracker,
 404                                   match->enums, *args, *args);
 405                 if (completion->tracker.have_completions ())
 406                   return {};
 407
 408                 /* If we don't have completions, let the
 409                    non-completion path throw on invalid enum value
 410                    below, so that completion processing stops.  */
 411               }
 412           }
 413
 414         if (check_for_argument (args, "--"))
 415           {
 416             /* Treat e.g., "backtrace -entry-values --" as if there
 417                was no argument after "-entry-values".  This makes
 418                parse_cli_var_enum throw an error with a suggestion of
 419                what are the valid options.  */
 420             args = nullptr;
 421           }
 422
 423         option_value val;
 424         val.enumeration = parse_cli_var_enum (args, match->enums);
 425         return option_def_and_value {*match, match_ctx, val};
 426       }
 427     case var_string:
 428       {
 429         if (check_for_argument (args, "--"))
 430           {
 431             /* Treat e.g., "maint test-options -string --" as if there
 432                was no argument after "-string".  */
 433             error (_("-%s requires an argument"), match->name);
 434           }
 435
 436         const char *arg_start = *args;
 437         std::string str = extract_string_maybe_quoted (args);
 438         if (*args == arg_start)
 439           error (_("-%s requires an argument"), match->name);
 440
 441         option_value val;
 442         val.string = xstrdup (str.c_str ());
 443         return option_def_and_value {*match, match_ctx, val};
 444       }
 445
 446     default:
 447       /* Not yet.  */
 448       gdb_assert_not_reached (_("option type not supported"));
 449     }
 450
 451   return {};
 452 }
 453
 454 /* See cli-option.h.  */
 455
 456 bool
 457 complete_options (completion_tracker &tracker,
 458                   const char **args,
 459                   process_options_mode mode,
 460                   gdb::array_view<const option_def_group> options_group)
 461 {
 462   const char *text = *args;
 463
 464   tracker.set_use_custom_word_point (true);
 465
 466   const char *delimiter = find_end_options_delimiter (text);
 467   bool have_delimiter = delimiter != nullptr;
 468
 469   if (text[0] == '-' && (!have_delimiter || *delimiter == '\0'))
 470     {
 471       parse_option_completion_info completion_info {nullptr, tracker};
 472
 473       while (1)
 474         {
 475           *args = skip_spaces (*args);
 476           completion_info.word = *args;
 477
 478           if (strcmp (*args, "-") == 0)
 479             {
 480               complete_on_options (options_group, tracker, *args + 1,
 481                                    completion_info.word);
 482             }
 483           else if (strcmp (*args, "--") == 0)
 484             {
 485               tracker.add_completion (make_unique_xstrdup (*args));
 486             }
 487           else if (**args == '-')
 488             {
 489               gdb::optional<option_def_and_value> ov
 490                 = parse_option (options_group, mode, have_delimiter,
 491                                 args, &completion_info);
 492               if (!ov && !tracker.have_completions ())
 493                 {
 494                   tracker.advance_custom_word_point_by (*args - text);
 495                   return mode == PROCESS_OPTIONS_REQUIRE_DELIMITER;
 496                 }
 497
 498               if (ov
 499                   && ov->option.type == var_boolean
 500                   && !ov->value.has_value ())
 501                 {
 502                   /* Looked like a boolean option, but we failed to
 503                      parse the value.  If this command requires a
 504                      delimiter, this value can't be the start of the
 505                      operands, so return true.  Otherwise, if the
 506                      command doesn't require a delimiter return false
 507                      so that the caller tries to complete on the
 508                      operand.  */
 509                   tracker.advance_custom_word_point_by (*args - text);
 510                   return mode == PROCESS_OPTIONS_REQUIRE_DELIMITER;
 511                 }
 512
 513               /* If we parsed an option with an argument, and reached
 514                  the end of the input string with no trailing space,
 515                  return true, so that our callers don't try to
 516                  complete anything by themselves.  E.g., this makes it
 517                  so that with:
 518
 519                   (gdb) frame apply all -limit 10[TAB]
 520
 521                  we don't try to complete on command names.  */
 522               if (ov
 523                   && !tracker.have_completions ()
 524                   && **args == '\0'
 525                   && *args > text && !isspace ((*args)[-1]))
 526                 {
 527                   tracker.advance_custom_word_point_by
 528                     (*args - text);
 529                   return true;
 530                 }
 531
 532               /* If the caller passed in a context, then it is
 533                  interested in the option argument values.  */
 534               if (ov && ov->ctx != nullptr)
 535                 save_option_value_in_ctx (ov);
 536             }
 537           else
 538             {
 539               tracker.advance_custom_word_point_by
 540                 (completion_info.word - text);
 541
 542               /* If the command requires a delimiter, but we haven't
 543                  seen one, then return true, so that the caller
 544                  doesn't try to complete on whatever follows options,
 545                  which for these commands should only be done if
 546                  there's a delimiter.  */
 547               if (mode == PROCESS_OPTIONS_REQUIRE_DELIMITER
 548                   && !have_delimiter)
 549                 {
 550                   /* If we reached the end of the input string, then
 551                      offer all options, since that's all the user can
 552                      type (plus "--").  */
 553                   if (completion_info.word[0] == '\0')
 554                     complete_on_all_options (tracker, options_group);
 555                   return true;
 556                 }
 557               else
 558                 return false;
 559             }
 560
 561           if (tracker.have_completions ())
 562             {
 563               tracker.advance_custom_word_point_by
 564                 (completion_info.word - text);
 565               return true;
 566             }
 567         }
 568     }
 569   else if (delimiter != nullptr)
 570     {
 571       tracker.advance_custom_word_point_by (delimiter - text);
 572       *args = delimiter;
 573       return false;
 574     }
 575
 576   return false;
 577 }
 578
 579 /* Save the parsed value in the option's context.  */
 580
 581 static void
 582 save_option_value_in_ctx (gdb::optional<option_def_and_value> &ov)
 583 {
 584   switch (ov->option.type)
 585     {
 586     case var_boolean:
 587       {
 588         bool value = ov->value.has_value () ? ov->value->boolean : true;
 589         *ov->option.var_address.boolean (ov->option, ov->ctx) = value;
 590       }
 591       break;
 592     case var_uinteger:
 593       *ov->option.var_address.uinteger (ov->option, ov->ctx)
 594         = ov->value->uinteger;
 595       break;
 596     case var_zuinteger_unlimited:
 597       *ov->option.var_address.integer (ov->option, ov->ctx)
 598         = ov->value->integer;
 599       break;
 600     case var_enum:
 601       *ov->option.var_address.enumeration (ov->option, ov->ctx)
 602         = ov->value->enumeration;
 603       break;
 604     case var_string:
 605       *ov->option.var_address.string (ov->option, ov->ctx)
 606         = ov->value->string;
 607       ov->value->string = nullptr;
 608       break;
 609     default:
 610       gdb_assert_not_reached ("unhandled option type");
 611     }
 612 }
 613
 614 /* See cli-option.h.  */
 615
 616 bool
 617 process_options (const char **args,
 618                  process_options_mode mode,
 619                  gdb::array_view<const option_def_group> options_group)
 620 {
 621   if (*args == nullptr)
 622     return false;
 623
 624   /* If ARGS starts with "-", look for a "--" sequence.  If one is
 625      found, then interpret everything up until the "--" as
 626      'gdb::option'-style command line options.  Otherwise, interpret
 627      ARGS as possibly the command's operands.  */
 628   bool have_delimiter = find_end_options_delimiter (*args) != nullptr;
 629
 630   if (mode == PROCESS_OPTIONS_REQUIRE_DELIMITER && !have_delimiter)
 631     return false;
 632
 633   bool processed_any = false;
 634
 635   while (1)
 636     {
 637       *args = skip_spaces (*args);
 638
 639       auto ov = parse_option (options_group, mode, have_delimiter, args);
 640       if (!ov)
 641         {
 642           if (processed_any)
 643             return true;
 644           return false;
 645         }
 646
 647       processed_any = true;
 648
 649       save_option_value_in_ctx (ov);
 650     }
 651 }
 652
 653 /* Helper for build_help.  Return a fragment of a help string showing
 654    OPT's possible values.  Returns NULL if OPT doesn't take an
 655    argument.  */
 656
 657 static const char *
 658 get_val_type_str (const option_def &opt, std::string &buffer)
 659 {
 660   if (!opt.have_argument)
 661     return nullptr;
 662
 663   switch (opt.type)
 664     {
 665     case var_boolean:
 666       return "[on|off]";
 667     case var_uinteger:
 668     case var_zuinteger_unlimited:
 669       return "NUMBER|unlimited";
 670     case var_enum:
 671       {
 672         buffer = "";
 673         for (size_t i = 0; opt.enums[i] != nullptr; i++)
 674           {
 675             if (i != 0)
 676               buffer += "|";
 677             buffer += opt.enums[i];
 678           }
 679         return buffer.c_str ();
 680       }
 681     case var_string:
 682       return "STRING";
 683     default:
 684       return nullptr;
 685     }
 686 }
 687
 688 /* Helper for build_help.  Appends an indented version of DOC into
 689    HELP.  */
 690
 691 static void
 692 append_indented_doc (const char *doc, std::string &help)
 693 {
 694   const char *p = doc;
 695   const char *n = strchr (p, '\n');
 696
 697   while (n != nullptr)
 698     {
 699       help += "    ";
 700       help.append (p, n - p + 1);
 701       p = n + 1;
 702       n = strchr (p, '\n');
 703     }
 704   help += "    ";
 705   help += p;
 706   help += '\n';
 707 }
 708
 709 /* Fill HELP with an auto-generated "help" string fragment for
 710    OPTIONS.  */
 711
 712 static void
 713 build_help_option (gdb::array_view<const option_def> options,
 714                    std::string &help)
 715 {
 716   std::string buffer;
 717
 718   for (const auto &o : options)
 719     {
 720       if (o.set_doc == nullptr)
 721         continue;
 722
 723       help += "  -";
 724       help += o.name;
 725
 726       const char *val_type_str = get_val_type_str (o, buffer);
 727       if (val_type_str != nullptr)
 728         {
 729           help += ' ';
 730           help += val_type_str;
 731         }
 732       help += "\n";
 733       append_indented_doc (o.set_doc, help);
 734       if (o.help_doc != nullptr)
 735         append_indented_doc (o.help_doc, help);
 736       help += '\n';
 737     }
 738 }
 739
 740 /* See cli-option.h.  */
 741
 742 std::string
 743 build_help (const char *help_tmpl,
 744             gdb::array_view<const option_def_group> options_group)
 745 {
 746   std::string help_str;
 747
 748   const char *p = strstr (help_tmpl, "%OPTIONS%");
 749   help_str.assign (help_tmpl, p);
 750
 751   for (const auto &grp : options_group)
 752     for (const auto &opt : grp.options)
 753       build_help_option (opt, help_str);
 754
 755   p += strlen ("%OPTIONS%");
 756   help_str.append (p);
 757
 758   return help_str;
 759 }
 760
 761 /* See cli-option.h.  */
 762
 763 void
 764 add_setshow_cmds_for_options (command_class cmd_class,
 765                               void *data,
 766                               gdb::array_view<const option_def> options,
 767                               struct cmd_list_element **set_list,
 768                               struct cmd_list_element **show_list)
 769 {
 770   for (const auto &option : options)
 771     {
 772       if (option.type == var_boolean)
 773         {
 774           add_setshow_boolean_cmd (option.name, cmd_class,
 775                                    option.var_address.boolean (option, data),
 776                                    option.set_doc, option.show_doc,
 777                                    option.help_doc,
 778                                    nullptr, option.show_cmd_cb,
 779                                    set_list, show_list);
 780         }
 781       else if (option.type == var_uinteger)
 782         {
 783           add_setshow_uinteger_cmd (option.name, cmd_class,
 784                                     option.var_address.uinteger (option, data),
 785                                     option.set_doc, option.show_doc,
 786                                     option.help_doc,
 787                                     nullptr, option.show_cmd_cb,
 788                                     set_list, show_list);
 789         }
 790       else if (option.type == var_zuinteger_unlimited)
 791         {
 792           add_setshow_zuinteger_unlimited_cmd
 793             (option.name, cmd_class,
 794              option.var_address.integer (option, data),
 795              option.set_doc, option.show_doc,
 796              option.help_doc,
 797              nullptr, option.show_cmd_cb,
 798              set_list, show_list);
 799         }
 800       else if (option.type == var_enum)
 801         {
 802           add_setshow_enum_cmd (option.name, cmd_class,
 803                                 option.enums,
 804                                 option.var_address.enumeration (option, data),
 805                                 option.set_doc, option.show_doc,
 806                                 option.help_doc,
 807                                 nullptr, option.show_cmd_cb,
 808                                 set_list, show_list);
 809         }
 810       else if (option.type == var_string)
 811         {
 812           add_setshow_string_cmd (option.name, cmd_class,
 813                                   option.var_address.string (option, data),
 814                                   option.set_doc, option.show_doc,
 815                                   option.help_doc,
 816                                   nullptr, option.show_cmd_cb,
 817                                   set_list, show_list);
 818         }
 819       else
 820         gdb_assert_not_reached (_("option type not handled"));
 821     }
 822 }
 823
 824 } /* namespace option */
 825 } /* namespace gdb */