gold/options.cc

   1 // options.c -- handle command line options for gold
   2
   3 // Copyright 2006, 2007 Free Software Foundation, Inc.
   4 // Written by Ian Lance Taylor <iant@google.com>.
   5
   6 // This file is part of gold.
   7
   8 // This program is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 3 of the License, or
  11 // (at your option) any later version.
  12
  13 // This program is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the Free Software
  20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21 // MA 02110-1301, USA.
  22
  23 #include "gold.h"
  24
  25 #include <iostream>
  26 #include <sys/stat.h>
  27 #include "filenames.h"
  28 #include "libiberty.h"
  29
  30 #include "options.h"
  31
  32 namespace gold
  33 {
  34
  35 // The information we keep for a single command line option.
  36
  37 struct options::One_option
  38 {
  39   // The single character option name, or '\0' if this is only a long
  40   // option.
  41   char short_option;
  42
  43   // The long option name, or NULL if this is only a short option.
  44   const char* long_option;
  45
  46   // Description of the option for --help output, or NULL if there is none.
  47   const char* doc;
  48
  49   // How to print the option name in --help output, or NULL to use the
  50   // default.
  51   const char* help_output;
  52
  53   // Long option dash control.  This is ignored if long_option is
  54   // NULL.
  55   enum
  56     {
  57       // Long option normally takes one dash; two dashes are also
  58       // accepted.
  59       ONE_DASH,
  60       // Long option normally takes two dashes; one dash is also
  61       // accepted.
  62       TWO_DASHES,
  63       // Long option always takes two dashes.
  64       EXACTLY_TWO_DASHES
  65     } dash;
  66
  67   // Function for special handling, or NULL.  Returns the number of
  68   // arguments to skip.  This will normally be at least 1, but it may
  69   // be 0 if this function changes *argv.  ARG points to the location
  70   // in *ARGV where the option starts, which may be helpful for a
  71   // short option.
  72   int (*special)(int argc, char** argv, char *arg, Command_line*);
  73
  74   // If this is a position independent option which does not take an
  75   // argument, this is the member function to call to record it.
  76   void (General_options::*general_noarg)();
  77
  78   // If this is a position independent function which takes an
  79   // argument, this is the member function to call to record it.
  80   void (General_options::*general_arg)(const char*);
  81
  82   // If this is a position dependent option which does not take an
  83   // argument, this is the member function to call to record it.
  84   void (Position_dependent_options::*dependent_noarg)();
  85
  86   // If this is a position dependent option which takes an argument,
  87   // this is the member function to record it.
  88   void (Position_dependent_options::*dependent_arg)(const char*);
  89
  90   // Return whether this option takes an argument.
  91   bool
  92   takes_argument() const
  93   { return this->general_arg != NULL || this->dependent_arg != NULL; }
  94 };
  95
  96 class options::Command_line_options
  97 {
  98  public:
  99   static const One_option options[];
 100   static const int options_size;
 101 };
 102
 103 } // End namespace gold.
 104
 105 namespace
 106 {
 107
 108 // Handle the special -l option, which adds an input file.
 109
 110 int
 111 library(int argc, char** argv, char* arg, gold::Command_line* cmdline)
 112 {
 113   return cmdline->process_l_option(argc, argv, arg);
 114 }
 115
 116 // Handle the special --start-group option.
 117
 118 int
 119 start_group(int, char**, char* arg, gold::Command_line* cmdline)
 120 {
 121   cmdline->start_group(arg);
 122   return 1;
 123 }
 124
 125 // Handle the special --end-group option.
 126
 127 int
 128 end_group(int, char**, char* arg, gold::Command_line* cmdline)
 129 {
 130   cmdline->end_group(arg);
 131   return 1;
 132 }
 133
 134 // Report usage information for ld --help, and exit.
 135
 136 int
 137 help(int, char**, char*, gold::Command_line*)
 138 {
 139   printf(_("Usage: %s [options] file...\nOptions:\n"), gold::program_name);
 140
 141   const int options_size = gold::options::Command_line_options::options_size;
 142   const gold::options::One_option* options =
 143     gold::options::Command_line_options::options;
 144   for (int i = 0; i < options_size; ++i)
 145     {
 146       if (options[i].doc == NULL)
 147         continue;
 148
 149       printf("  ");
 150       int len = 2;
 151       bool comma = false;
 152
 153       int j = i;
 154       do
 155         {
 156           if (options[j].help_output != NULL)
 157             {
 158               if (comma)
 159                 {
 160                   printf(", ");
 161                   len += 2;
 162                 }
 163               printf(options[j].help_output);
 164               len += std::strlen(options[i].help_output);
 165               comma = true;
 166             }
 167           else
 168             {
 169               if (options[j].short_option != '\0')
 170                 {
 171                   if (comma)
 172                     {
 173                       printf(", ");
 174                       len += 2;
 175                     }
 176                   printf("-%c", options[j].short_option);
 177                   len += 2;
 178                   comma = true;
 179                 }
 180
 181               if (options[j].long_option != NULL)
 182                 {
 183                   if (comma)
 184                     {
 185                       printf(", ");
 186                       len += 2;
 187                     }
 188                   if (options[j].dash == gold::options::One_option::ONE_DASH)
 189                     {
 190                       printf("-");
 191                       ++len;
 192                     }
 193                   else
 194                     {
 195                       printf("--");
 196                       len += 2;
 197                     }
 198                   printf("%s", options[j].long_option);
 199                   len += std::strlen(options[j].long_option);
 200                   comma = true;
 201                 }
 202             }
 203           ++j;
 204         }
 205       while (j < options_size && options[j].doc == NULL);
 206
 207       if (len >= 30)
 208         {
 209           printf("\n");
 210           len = 0;
 211         }
 212       for (; len < 30; ++len)
 213         std::putchar(' ');
 214
 215       std::puts(options[i].doc);
 216     }
 217
 218   ::exit(0);
 219
 220   return 0;
 221 }
 222
 223 // Report version information.
 224
 225 int
 226 version(int, char**, char* opt, gold::Command_line*)
 227 {
 228   gold::print_version(opt[0] == 'v' && opt[1] == '\0');
 229   ::exit(0);
 230   return 0;
 231 }
 232
 233 // If the default sysroot is relocatable, try relocating it based on
 234 // the prefix FROM.
 235
 236 char*
 237 get_relative_sysroot(const char* from)
 238 {
 239   char* path = make_relative_prefix(gold::program_name, from,
 240                                     TARGET_SYSTEM_ROOT);
 241   if (path != NULL)
 242     {
 243       struct stat s;
 244       if (::stat(path, &s) == 0 && S_ISDIR(s.st_mode))
 245         return path;
 246       free(path);
 247     }
 248
 249   return NULL;
 250 }
 251
 252 // Return the default sysroot.  This is set by the --with-sysroot
 253 // option to configure.
 254
 255 std::string
 256 get_default_sysroot()
 257 {
 258   const char* sysroot = TARGET_SYSTEM_ROOT;
 259   if (*sysroot == '\0')
 260     return "";
 261
 262   if (TARGET_SYSTEM_ROOT_RELOCATABLE)
 263     {
 264       char* path = get_relative_sysroot (BINDIR);
 265       if (path == NULL)
 266         path = get_relative_sysroot (TOOLBINDIR);
 267       if (path != NULL)
 268         {
 269           std::string ret = path;
 270           free(path);
 271           return ret;
 272         }
 273     }
 274
 275   return sysroot;
 276 }
 277
 278 } // End anonymous namespace.
 279
 280 namespace gold
 281 {
 282
 283 // Helper macros used to specify the options.  We could also do this
 284 // using constructors, but then g++ would generate code to initialize
 285 // the array.  We want the array to be initialized statically so that
 286 // we get better startup time.
 287
 288 #define GENERAL_NOARG(short_option, long_option, doc, help, dash, func) \
 289   { short_option, long_option, doc, help, options::One_option::dash, \
 290       NULL, func, NULL, NULL, NULL }
 291 #define GENERAL_ARG(short_option, long_option, doc, help, dash, func)   \
 292   { short_option, long_option, doc, help, options::One_option::dash, \
 293       NULL, NULL, func, NULL, NULL }
 294 #define POSDEP_NOARG(short_option, long_option, doc, help, dash, func)  \
 295   { short_option, long_option, doc, help, options::One_option::dash, \
 296       NULL,  NULL, NULL, func, NULL }
 297 #define POSDEP_ARG(short_option, long_option, doc, help, dash, func)    \
 298   { short_option, long_option, doc, help, options::One_option::dash, \
 299       NULL, NULL, NULL, NULL, func }
 300 #define SPECIAL(short_option, long_option, doc, help, dash, func)       \
 301   { short_option, long_option, doc, help, options::One_option::dash, \
 302       func, NULL, NULL, NULL, NULL }
 303
 304 // Here is the actual list of options which we accept.
 305
 306 const options::One_option
 307 options::Command_line_options::options[] =
 308 {
 309   POSDEP_NOARG('\0', "as-needed",
 310                N_("Only set DT_NEEDED for dynamic libs if used"),
 311                NULL, TWO_DASHES, &Position_dependent_options::set_as_needed),
 312   POSDEP_NOARG('\0', "no-as-needed",
 313                N_("Always DT_NEEDED for dynamic libs (default)"),
 314                NULL, TWO_DASHES, &Position_dependent_options::clear_as_needed),
 315   POSDEP_NOARG('\0', "Bdynamic",
 316                N_("-l searches for shared libraries"),
 317                NULL, ONE_DASH,
 318                &Position_dependent_options::set_dynamic_search),
 319   POSDEP_NOARG('\0', "Bstatic",
 320                N_("-l does not search for shared libraries"),
 321                NULL, ONE_DASH,
 322                &Position_dependent_options::set_static_search),
 323   GENERAL_NOARG('\0', "Bsymbolic", N_("Bind defined symbols locally"),
 324                 NULL, ONE_DASH, &General_options::set_symbolic),
 325   GENERAL_NOARG('E', "export-dynamic", N_("Export all dynamic symbols"),
 326                 NULL, TWO_DASHES, &General_options::set_export_dynamic),
 327   GENERAL_NOARG('\0', "eh-frame-hdr", N_("Create exception frame header"),
 328                 NULL, TWO_DASHES, &General_options::set_create_eh_frame_hdr),
 329   GENERAL_ARG('I', "dynamic-linker", N_("Set dynamic linker path"),
 330               N_("-I PROGRAM, --dynamic-linker PROGRAM"), TWO_DASHES,
 331               &General_options::set_dynamic_linker),
 332   SPECIAL('l', "library", N_("Search for library LIBNAME"),
 333           N_("-lLIBNAME, --library LIBNAME"), TWO_DASHES,
 334           &library),
 335   GENERAL_ARG('L', "library-path", N_("Add directory to search path"),
 336               N_("-L DIR, --library-path DIR"), TWO_DASHES,
 337               &General_options::add_to_search_path),
 338   GENERAL_ARG('m', NULL, N_("Ignored for compatibility"), NULL, ONE_DASH,
 339               &General_options::ignore),
 340   GENERAL_ARG('o', "output", N_("Set output file name"),
 341               N_("-o FILE, --output FILE"), TWO_DASHES,
 342               &General_options::set_output_file_name),
 343   GENERAL_ARG('O', NULL, N_("Optimize output file size"),
 344               N_("-O level"), ONE_DASH,
 345               &General_options::set_optimization_level),
 346   GENERAL_NOARG('r', NULL, N_("Generate relocatable output"), NULL,
 347                 ONE_DASH, &General_options::set_relocatable),
 348   GENERAL_ARG('R', "rpath", N_("Add DIR to runtime search path"),
 349               N_("-R DIR, -rpath DIR"), ONE_DASH,
 350               &General_options::add_to_rpath),
 351   GENERAL_ARG('\0', "rpath-link",
 352               N_("Add DIR to link time shared library search path"),
 353               N_("--rpath-link DIR"), TWO_DASHES,
 354               &General_options::add_to_rpath_link),
 355   GENERAL_NOARG('s', "strip-all", N_("Strip all symbols"), NULL,
 356                 TWO_DASHES, &General_options::set_strip_all),
 357   GENERAL_NOARG('S', "strip-debug", N_("Strip debugging information"), NULL,
 358                 TWO_DASHES, &General_options::set_strip_debug),
 359   GENERAL_NOARG('\0', "shared", N_("Generate shared library"),
 360                 NULL, ONE_DASH, &General_options::set_shared),
 361   GENERAL_NOARG('\0', "static", N_("Do not link against shared libraries"),
 362                 NULL, ONE_DASH, &General_options::set_static),
 363   GENERAL_NOARG('\0', "stats", N_("Print resource usage statistics"),
 364                 NULL, TWO_DASHES, &General_options::set_stats),
 365   GENERAL_ARG('\0', "sysroot", N_("Set target system root directory"),
 366               N_("--sysroot DIR"), TWO_DASHES, &General_options::set_sysroot),
 367   GENERAL_ARG('\0', "Ttext", N_("Set the address of the .text section"),
 368               N_("-Ttext ADDRESS"), ONE_DASH,
 369               &General_options::set_text_segment_address),
 370   GENERAL_NOARG('\0', "threads", N_("Run the linker multi-threaded"),
 371                 NULL, TWO_DASHES, &General_options::set_threads),
 372   GENERAL_NOARG('\0', "no-threads", N_("Do not run the linker multi-threaded"),
 373                 NULL, TWO_DASHES, &General_options::clear_threads),
 374   GENERAL_ARG('\0', "thread-count", N_("Number of threads to use"),
 375               N_("--thread-count COUNT"), TWO_DASHES,
 376               &General_options::set_thread_count),
 377   GENERAL_ARG('\0', "thread-count-initial",
 378               N_("Number of threads to use in initial pass"),
 379               N_("--thread-count-initial COUNT"), TWO_DASHES,
 380               &General_options::set_thread_count_initial),
 381   GENERAL_ARG('\0', "thread-count-middle",
 382               N_("Number of threads to use in middle pass"),
 383               N_("--thread-count-middle COUNT"), TWO_DASHES,
 384               &General_options::set_thread_count_middle),
 385   GENERAL_ARG('\0', "thread-count-final",
 386               N_("Number of threads to use in final pass"),
 387               N_("--thread-count-final COUNT"), TWO_DASHES,
 388               &General_options::set_thread_count_final),
 389   POSDEP_NOARG('\0', "whole-archive",
 390                N_("Include all archive contents"),
 391                NULL, TWO_DASHES,
 392                &Position_dependent_options::set_whole_archive),
 393   POSDEP_NOARG('\0', "no-whole-archive",
 394                N_("Include only needed archive contents"),
 395                NULL, TWO_DASHES,
 396                &Position_dependent_options::clear_whole_archive),
 397   SPECIAL('(', "start-group", N_("Start a library search group"), NULL,
 398           TWO_DASHES, &start_group),
 399   SPECIAL(')', "end-group", N_("End a library search group"), NULL,
 400           TWO_DASHES, &end_group),
 401   SPECIAL('\0', "help", N_("Report usage information"), NULL,
 402           TWO_DASHES, &help),
 403   SPECIAL('v', "version", N_("Report version information"), NULL,
 404           TWO_DASHES, &version)
 405 };
 406
 407 const int options::Command_line_options::options_size =
 408   sizeof (options) / sizeof (options[0]);
 409
 410 // The default values for the general options.
 411
 412 General_options::General_options()
 413   : export_dynamic_(false),
 414     dynamic_linker_(NULL),
 415     search_path_(),
 416     optimization_level_(0),
 417     output_file_name_("a.out"),
 418     is_relocatable_(false),
 419     strip_(STRIP_NONE),
 420     symbolic_(false),
 421     create_eh_frame_hdr_(false),
 422     rpath_(),
 423     rpath_link_(),
 424     is_shared_(false),
 425     is_static_(false),
 426     print_stats_(false),
 427     sysroot_(),
 428     text_segment_address_(-1U),   // -1 indicates value not set by user
 429     threads_(false),
 430     thread_count_initial_(0),
 431     thread_count_middle_(0),
 432     thread_count_final_(0)
 433 {
 434 }
 435
 436 // The default values for the position dependent options.
 437
 438 Position_dependent_options::Position_dependent_options()
 439   : do_static_search_(false),
 440     as_needed_(false),
 441     include_whole_archive_(false)
 442 {
 443 }
 444
 445 // Add the sysroot, if any, to the search paths.
 446
 447 void
 448 General_options::add_sysroot()
 449 {
 450   if (this->sysroot_.empty())
 451     {
 452       this->sysroot_ = get_default_sysroot();
 453       if (this->sysroot_.empty())
 454         return;
 455     }
 456
 457   const char* sysroot = this->sysroot_.c_str();
 458   char* canonical_sysroot = lrealpath(sysroot);
 459
 460   for (Dir_list::iterator p = this->search_path_.begin();
 461        p != this->search_path_.end();
 462        ++p)
 463     p->add_sysroot(sysroot, canonical_sysroot);
 464
 465   free(canonical_sysroot);
 466 }
 467
 468 // Search_directory methods.
 469
 470 // This is called if we have a sysroot.  Apply the sysroot if
 471 // appropriate.  Record whether the directory is in the sysroot.
 472
 473 void
 474 Search_directory::add_sysroot(const char* sysroot,
 475                               const char* canonical_sysroot)
 476 {
 477   gold_assert(*sysroot != '\0');
 478   if (this->put_in_sysroot_)
 479     {
 480       if (!IS_DIR_SEPARATOR(this->name_[0])
 481           && !IS_DIR_SEPARATOR(sysroot[strlen(sysroot) - 1]))
 482         this->name_ = '/' + this->name_;
 483       this->name_ = sysroot + this->name_;
 484       this->is_in_sysroot_ = true;
 485     }
 486   else
 487     {
 488       // Check whether this entry is in the sysroot.  To do this
 489       // correctly, we need to use canonical names.  Otherwise we will
 490       // get confused by the ../../.. paths that gcc tends to use.
 491       char* canonical_name = lrealpath(this->name_.c_str());
 492       int canonical_name_len = strlen(canonical_name);
 493       int canonical_sysroot_len = strlen(canonical_sysroot);
 494       if (canonical_name_len > canonical_sysroot_len
 495           && IS_DIR_SEPARATOR(canonical_name[canonical_sysroot_len]))
 496         {
 497           canonical_name[canonical_sysroot_len] = '\0';
 498           if (FILENAME_CMP(canonical_name, canonical_sysroot) == 0)
 499             this->is_in_sysroot_ = true;
 500         }
 501       free(canonical_name);
 502     }
 503 }
 504
 505 // Input_arguments methods.
 506
 507 // Add a file to the list.
 508
 509 void
 510 Input_arguments::add_file(const Input_file_argument& file)
 511 {
 512   if (!this->in_group_)
 513     this->input_argument_list_.push_back(Input_argument(file));
 514   else
 515     {
 516       gold_assert(!this->input_argument_list_.empty());
 517       gold_assert(this->input_argument_list_.back().is_group());
 518       this->input_argument_list_.back().group()->add_file(file);
 519     }
 520 }
 521
 522 // Start a group.
 523
 524 void
 525 Input_arguments::start_group()
 526 {
 527   gold_assert(!this->in_group_);
 528   Input_file_group* group = new Input_file_group();
 529   this->input_argument_list_.push_back(Input_argument(group));
 530   this->in_group_ = true;
 531 }
 532
 533 // End a group.
 534
 535 void
 536 Input_arguments::end_group()
 537 {
 538   gold_assert(this->in_group_);
 539   this->in_group_ = false;
 540 }
 541
 542 // Command_line options.
 543
 544 Command_line::Command_line()
 545   : options_(), position_options_(), inputs_()
 546 {
 547 }
 548
 549 // Process the command line options.
 550
 551 void
 552 Command_line::process(int argc, char** argv)
 553 {
 554   const int options_size = options::Command_line_options::options_size;
 555   const options::One_option* options =
 556     options::Command_line_options::options;
 557   bool no_more_options = false;
 558   int i = 0;
 559   while (i < argc)
 560     {
 561       if (argv[i][0] != '-' || no_more_options)
 562         {
 563           this->add_file(argv[i], false);
 564           ++i;
 565           continue;
 566         }
 567
 568       // Option starting with '-'.
 569       int dashes = 1;
 570       if (argv[i][1] == '-')
 571         {
 572           dashes = 2;
 573           if (argv[i][2] == '\0')
 574             {
 575               no_more_options = true;
 576               continue;
 577             }
 578         }
 579
 580       // Look for a long option match.
 581       char* opt = argv[i] + dashes;
 582       char first = opt[0];
 583       int skiparg = 0;
 584       char* arg = strchr(opt, '=');
 585       bool argument_with_equals = arg != NULL;
 586       if (arg != NULL)
 587         {
 588           *arg = '\0';
 589           ++arg;
 590         }
 591       else if (i + 1 < argc)
 592         {
 593           arg = argv[i + 1];
 594           skiparg = 1;
 595         }
 596
 597       int j;
 598       for (j = 0; j < options_size; ++j)
 599         {
 600           if (options[j].long_option != NULL
 601               && (dashes == 2
 602                   || (options[j].dash
 603                       != options::One_option::EXACTLY_TWO_DASHES))
 604               && first == options[j].long_option[0]
 605               && strcmp(opt, options[j].long_option) == 0)
 606             {
 607               if (options[j].special)
 608                 i += options[j].special(argc - 1, argv + i, opt, this);
 609               else
 610                 {
 611                   if (!options[j].takes_argument())
 612                     {
 613                       if (argument_with_equals)
 614                         this->usage(_("unexpected argument"), argv[i]);
 615                       arg = NULL;
 616                       skiparg = 0;
 617                     }
 618                   else
 619                     {
 620                       if (arg == NULL)
 621                         this->usage(_("missing argument"), argv[i]);
 622                     }
 623                   this->apply_option(options[j], arg);
 624                   i += skiparg + 1;
 625                 }
 626               break;
 627             }
 628         }
 629       if (j < options_size)
 630         continue;
 631
 632       // If we saw two dashes, we need to see a long option.
 633       if (dashes == 2)
 634         this->usage(_("unknown option"), argv[i]);
 635
 636       // Look for a short option match.  There may be more than one
 637       // short option in a given argument.
 638       bool done = false;
 639       char* s = argv[i] + 1;
 640       ++i;
 641       while (*s != '\0' && !done)
 642         {
 643           char opt = *s;
 644           int j;
 645           for (j = 0; j < options_size; ++j)
 646             {
 647               if (options[j].short_option == opt)
 648                 {
 649                   if (options[j].special)
 650                     {
 651                       // Undo the argument skip done above.
 652                       --i;
 653                       i += options[j].special(argc - i, argv + i, s, this);
 654                       done = true;
 655                     }
 656                   else
 657                     {
 658                       arg = NULL;
 659                       if (options[j].takes_argument())
 660                         {
 661                           if (s[1] != '\0')
 662                             {
 663                               arg = s + 1;
 664                               done = true;
 665                             }
 666                           else if (i < argc)
 667                             {
 668                               arg = argv[i];
 669                               ++i;
 670                             }
 671                           else
 672                             this->usage(_("missing argument"), opt);
 673                         }
 674                       this->apply_option(options[j], arg);
 675                     }
 676                   break;
 677                 }
 678             }
 679
 680           if (j >= options_size)
 681             this->usage(_("unknown option"), *s);
 682
 683           ++s;
 684         }
 685     }
 686
 687   if (this->inputs_.in_group())
 688     {
 689       fprintf(stderr, _("%s: missing group end"), program_name);
 690       this->usage();
 691     }
 692
 693   // FIXME: We should only do this when configured in native mode.
 694   this->options_.add_to_search_path_with_sysroot("/lib");
 695   this->options_.add_to_search_path_with_sysroot("/usr/lib");
 696
 697   this->options_.add_sysroot();
 698
 699   // Ensure options don't contradict each other and are otherwise kosher.
 700   this->normalize_options();
 701 }
 702
 703 // Ensure options don't contradict each other and are otherwise kosher.
 704
 705 void
 706 Command_line::normalize_options()
 707 {
 708   // If the user specifies both -s and -r, convert the -s as -S.
 709   // -r requires us to keep externally visible symbols!
 710   if (this->options_.strip_all() && this->options_.is_relocatable())
 711     {
 712       // Clears the strip_all() status, replacing it with strip_debug().
 713       this->options_.set_strip_debug();
 714     }
 715
 716   // FIXME: we can/should be doing a lot more sanity checking here.
 717 }
 718
 719
 720 // Apply a command line option.
 721
 722 void
 723 Command_line::apply_option(const options::One_option& opt,
 724                            const char* arg)
 725 {
 726   if (arg == NULL)
 727     {
 728       if (opt.general_noarg)
 729         (this->options_.*(opt.general_noarg))();
 730       else if (opt.dependent_noarg)
 731         (this->position_options_.*(opt.dependent_noarg))();
 732       else
 733         gold_unreachable();
 734     }
 735   else
 736     {
 737       if (opt.general_arg)
 738         (this->options_.*(opt.general_arg))(arg);
 739       else if (opt.dependent_arg)
 740         (this->position_options_.*(opt.dependent_arg))(arg);
 741       else
 742         gold_unreachable();
 743     }
 744 }
 745
 746 // Add an input file or library.
 747
 748 void
 749 Command_line::add_file(const char* name, bool is_lib)
 750 {
 751   Input_file_argument file(name, is_lib, "", this->position_options_);
 752   this->inputs_.add_file(file);
 753 }
 754
 755 // Handle the -l option, which requires special treatment.
 756
 757 int
 758 Command_line::process_l_option(int argc, char** argv, char* arg)
 759 {
 760   int ret;
 761   const char* libname;
 762   if (arg[1] != '\0')
 763     {
 764       ret = 1;
 765       libname = arg + 1;
 766     }
 767   else if (argc > 1)
 768     {
 769       ret = 2;
 770       libname = argv[argc + 1];
 771     }
 772   else
 773     this->usage(_("missing argument"), arg);
 774
 775   this->add_file(libname, true);
 776
 777   return ret;
 778 }
 779
 780 // Handle the --start-group option.
 781
 782 void
 783 Command_line::start_group(const char* arg)
 784 {
 785   if (this->inputs_.in_group())
 786     this->usage(_("may not nest groups"), arg);
 787   this->inputs_.start_group();
 788 }
 789
 790 // Handle the --end-group option.
 791
 792 void
 793 Command_line::end_group(const char* arg)
 794 {
 795   if (!this->inputs_.in_group())
 796     this->usage(_("group end without group start"), arg);
 797   this->inputs_.end_group();
 798 }
 799
 800 // Report a usage error.  */
 801
 802 void
 803 Command_line::usage()
 804 {
 805   fprintf(stderr,
 806           _("%s: use the --help option for usage information\n"),
 807           program_name);
 808   ::exit(1);
 809 }
 810
 811 void
 812 Command_line::usage(const char* msg, const char *opt)
 813 {
 814   fprintf(stderr,
 815           _("%s: %s: %s\n"),
 816           program_name, opt, msg);
 817   this->usage();
 818 }
 819
 820 void
 821 Command_line::usage(const char* msg, char opt)
 822 {
 823   fprintf(stderr,
 824           _("%s: -%c: %s\n"),
 825           program_name, opt, msg);
 826   this->usage();
 827 }
 828
 829 } // End namespace gold.