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 <iostream>
  24
  25 #include "gold.h"
  26 #include "options.h"
  27
  28 namespace gold
  29 {
  30
  31 // The information we keep for a single command line option.
  32
  33 struct options::One_option
  34 {
  35   // The single character option name, or '\0' if this is only a long
  36   // option.
  37   char short_option;
  38
  39   // The long option name, or NULL if this is only a short option.
  40   const char* long_option;
  41
  42   // Description of the option for --help output, or NULL if there is none.
  43   const char* doc;
  44
  45   // How to print the option name in --help output, or NULL to use the
  46   // default.
  47   const char* help_output;
  48
  49   // Long option dash control.  This is ignored if long_option is
  50   // NULL.
  51   enum
  52     {
  53       // Long option normally takes one dash; two dashes are also
  54       // accepted.
  55       ONE_DASH,
  56       // Long option normally takes two dashes; one dash is also
  57       // accepted.
  58       TWO_DASHES,
  59       // Long option always takes two dashes.
  60       EXACTLY_TWO_DASHES
  61     } dash;
  62
  63   // Function for special handling, or NULL.  Returns the number of
  64   // arguments to skip.  This will normally be at least 1, but it may
  65   // be 0 if this function changes *argv.  ARG points to the location
  66   // in *ARGV where the option starts, which may be helpful for a
  67   // short option.
  68   int (*special)(int argc, char** argv, char *arg, Command_line*);
  69
  70   // If this is a position independent option which does not take an
  71   // argument, this is the member function to call to record it.
  72   void (General_options::*general_noarg)();
  73
  74   // If this is a position independent function which takes an
  75   // argument, this is the member function to call to record it.
  76   void (General_options::*general_arg)(const char*);
  77
  78   // If this is a position dependent option which does not take an
  79   // argument, this is the member function to call to record it.
  80   void (Position_dependent_options::*dependent_noarg)();
  81
  82   // If this is a position dependent option which takes an argument,
  83   // this is the member function to record it.
  84   void (Position_dependent_options::*dependent_arg)(const char*);
  85
  86   // Return whether this option takes an argument.
  87   bool
  88   takes_argument() const
  89   { return this->general_arg != NULL || this->dependent_arg != NULL; }
  90 };
  91
  92 class options::Command_line_options
  93 {
  94  public:
  95   static const One_option options[];
  96   static const int options_size;
  97 };
  98
  99 } // End namespace gold.
 100
 101 namespace
 102 {
 103
 104 // Handle the special -l option, which adds an input file.
 105
 106 int
 107 library(int argc, char** argv, char* arg, gold::Command_line* cmdline)
 108 {
 109   return cmdline->process_l_option(argc, argv, arg);
 110 }
 111
 112 // Handle the special --start-group option.
 113
 114 int
 115 start_group(int, char**, char* arg, gold::Command_line* cmdline)
 116 {
 117   cmdline->start_group(arg);
 118   return 1;
 119 }
 120
 121 // Handle the special --end-group option.
 122
 123 int
 124 end_group(int, char**, char* arg, gold::Command_line* cmdline)
 125 {
 126   cmdline->end_group(arg);
 127   return 1;
 128 }
 129
 130 // Report usage information for ld --help, and exit.
 131
 132 int
 133 help(int, char**, char*, gold::Command_line*)
 134 {
 135   printf(_("Usage: %s [options] file...\nOptions:\n"), gold::program_name);
 136
 137   const int options_size = gold::options::Command_line_options::options_size;
 138   const gold::options::One_option* options =
 139     gold::options::Command_line_options::options;
 140   for (int i = 0; i < options_size; ++i)
 141     {
 142       if (options[i].doc == NULL)
 143         continue;
 144
 145       printf("  ");
 146       int len = 2;
 147       bool comma = false;
 148
 149       int j = i;
 150       do
 151         {
 152           if (options[j].help_output != NULL)
 153             {
 154               if (comma)
 155                 {
 156                   printf(", ");
 157                   len += 2;
 158                 }
 159               printf(options[j].help_output);
 160               len += std::strlen(options[i].help_output);
 161               comma = true;
 162             }
 163           else
 164             {
 165               if (options[j].short_option != '\0')
 166                 {
 167                   if (comma)
 168                     {
 169                       printf(", ");
 170                       len += 2;
 171                     }
 172                   printf("-%c", options[j].short_option);
 173                   len += 2;
 174                   comma = true;
 175                 }
 176
 177               if (options[j].long_option != NULL)
 178                 {
 179                   if (comma)
 180                     {
 181                       printf(", ");
 182                       len += 2;
 183                     }
 184                   if (options[j].dash == gold::options::One_option::ONE_DASH)
 185                     {
 186                       printf("-");
 187                       ++len;
 188                     }
 189                   else
 190                     {
 191                       printf("--");
 192                       len += 2;
 193                     }
 194                   printf("%s", options[j].long_option);
 195                   len += std::strlen(options[j].long_option);
 196                   comma = true;
 197                 }
 198             }
 199           ++j;
 200         }
 201       while (j < options_size && options[j].doc == NULL);
 202
 203       if (len >= 30)
 204         {
 205           printf("\n");
 206           len = 0;
 207         }
 208       for (; len < 30; ++len)
 209         std::putchar(' ');
 210
 211       std::puts(options[i].doc);
 212     }
 213
 214   gold::gold_exit(true);
 215
 216   return 0;
 217 }
 218
 219 } // End anonymous namespace.
 220
 221 namespace gold
 222 {
 223
 224 // Helper macros used to specify the options.  We could also do this
 225 // using constructors, but then g++ would generate code to initialize
 226 // the array.  We want the array to be initialized statically so that
 227 // we get better startup time.
 228
 229 #define GENERAL_NOARG(short_option, long_option, doc, help, dash, func) \
 230   { short_option, long_option, doc, help, options::One_option::dash, \
 231       NULL, func, NULL, NULL, NULL }
 232 #define GENERAL_ARG(short_option, long_option, doc, help, dash, func)   \
 233   { short_option, long_option, doc, help, options::One_option::dash, \
 234       NULL, NULL, func, NULL, NULL }
 235 #define POSDEP_NOARG(short_option, long_option, doc, help, dash, func)  \
 236   { short_option, long_option, doc, help, options::One_option::dash, \
 237       NULL,  NULL, NULL, func, NULL }
 238 #define POSDEP_ARG(short_option, long_option, doc, help, dash, func)    \
 239   { short_option, long_option, doc, help, options::One_option::dash, \
 240       NULL, NULL, NULL, NULL, func }
 241 #define SPECIAL(short_option, long_option, doc, help, dash, func)       \
 242   { short_option, long_option, doc, help, options::One_option::dash, \
 243       func, NULL, NULL, NULL, NULL }
 244
 245 // Here is the actual list of options which we accept.
 246
 247 const options::One_option
 248 options::Command_line_options::options[] =
 249 {
 250   SPECIAL('l', "library", N_("Search for library LIBNAME"),
 251           N_("-lLIBNAME, --library LIBNAME"), TWO_DASHES,
 252           &library),
 253   SPECIAL('(', "start-group", N_("Start a library search group"), NULL,
 254           TWO_DASHES, &start_group),
 255   SPECIAL(')', "end-group", N_("End a library search group"), NULL,
 256           TWO_DASHES, &end_group),
 257   GENERAL_NOARG('E', "export-dynamic", N_("Export all dynamic symbols"),
 258                 NULL, TWO_DASHES, &General_options::set_export_dynamic),
 259   GENERAL_ARG('I', "dynamic-linker", N_("Set dynamic linker path"),
 260               N_("-I PROGRAM, --dynamic-linker PROGRAM"), TWO_DASHES,
 261               &General_options::set_dynamic_linker),
 262   GENERAL_ARG('L', "library-path", N_("Add directory to search path"),
 263               N_("-L DIR, --library-path DIR"), TWO_DASHES,
 264               &General_options::add_to_search_path),
 265   GENERAL_ARG('m', NULL, N_("Ignored for compatibility"), NULL, ONE_DASH,
 266               &General_options::ignore),
 267   GENERAL_ARG('O', NULL, N_("Optimize output file size"),
 268               N_("-O level"), ONE_DASH,
 269               &General_options::set_optimization_level),
 270   GENERAL_ARG('o', "output", N_("Set output file name"),
 271               N_("-o FILE, --output FILE"), TWO_DASHES,
 272               &General_options::set_output_file_name),
 273   GENERAL_NOARG('r', NULL, N_("Generate relocatable output"), NULL,
 274                 ONE_DASH, &General_options::set_relocatable),
 275   GENERAL_ARG('R', "rpath", N_("Add DIR to runtime search path"),
 276               N_("-R DIR, -rpath DIR"), ONE_DASH,
 277               &General_options::add_to_rpath),
 278   GENERAL_NOARG('\0', "eh-frame-hdr", N_("Create exception frame header"),
 279                 NULL, TWO_DASHES, &General_options::set_create_eh_frame_hdr),
 280   GENERAL_ARG('\0', "rpath-link",
 281               N_("Add DIR to link time shared library search path"),
 282               N_("--rpath-link DIR"), TWO_DASHES,
 283               &General_options::add_to_rpath_link),
 284   GENERAL_NOARG('\0', "shared", N_("Generate shared library"),
 285                 NULL, ONE_DASH, &General_options::set_shared),
 286   GENERAL_NOARG('\0', "static", N_("Do not link against shared libraries"),
 287                 NULL, ONE_DASH, &General_options::set_static),
 288   POSDEP_NOARG('\0', "as-needed",
 289                N_("Only set DT_NEEDED for dynamic libs if used"),
 290                NULL, TWO_DASHES, &Position_dependent_options::set_as_needed),
 291   POSDEP_NOARG('\0', "no-as-needed",
 292                N_("Always DT_NEEDED for dynamic libs (default)"),
 293                NULL, TWO_DASHES, &Position_dependent_options::clear_as_needed),
 294   POSDEP_NOARG('\0', "whole-archive",
 295                N_("Include all archive contents"),
 296                NULL, TWO_DASHES,
 297                &Position_dependent_options::set_whole_archive),
 298   POSDEP_NOARG('\0', "no-whole-archive",
 299                N_("Include only needed archive contents"),
 300                NULL, TWO_DASHES,
 301                &Position_dependent_options::clear_whole_archive),
 302   SPECIAL('\0', "help", N_("Report usage information"), NULL,
 303           TWO_DASHES, &help)
 304 };
 305
 306 const int options::Command_line_options::options_size =
 307   sizeof (options) / sizeof (options[0]);
 308
 309 // The default values for the general options.
 310
 311 General_options::General_options()
 312   : export_dynamic_(false),
 313     dynamic_linker_(NULL),
 314     search_path_(),
 315     optimization_level_(0),
 316     output_file_name_("a.out"),
 317     is_relocatable_(false),
 318     create_eh_frame_hdr_(false),
 319     rpath_(),
 320     rpath_link_(),
 321     is_shared_(false),
 322     is_static_(false)
 323 {
 324 }
 325
 326 // The default values for the position dependent options.
 327
 328 Position_dependent_options::Position_dependent_options()
 329   : do_static_search_(false),
 330     as_needed_(false),
 331     include_whole_archive_(false)
 332 {
 333 }
 334
 335 // Input_arguments methods.
 336
 337 // Add a file to the list.
 338
 339 void
 340 Input_arguments::add_file(const Input_file_argument& file)
 341 {
 342   if (!this->in_group_)
 343     this->input_argument_list_.push_back(Input_argument(file));
 344   else
 345     {
 346       gold_assert(!this->input_argument_list_.empty());
 347       gold_assert(this->input_argument_list_.back().is_group());
 348       this->input_argument_list_.back().group()->add_file(file);
 349     }
 350 }
 351
 352 // Start a group.
 353
 354 void
 355 Input_arguments::start_group()
 356 {
 357   gold_assert(!this->in_group_);
 358   Input_file_group* group = new Input_file_group();
 359   this->input_argument_list_.push_back(Input_argument(group));
 360   this->in_group_ = true;
 361 }
 362
 363 // End a group.
 364
 365 void
 366 Input_arguments::end_group()
 367 {
 368   gold_assert(this->in_group_);
 369   this->in_group_ = false;
 370 }
 371
 372 // Command_line options.
 373
 374 Command_line::Command_line()
 375   : options_(), position_options_(), inputs_()
 376 {
 377 }
 378
 379 // Process the command line options.
 380
 381 void
 382 Command_line::process(int argc, char** argv)
 383 {
 384   const int options_size = options::Command_line_options::options_size;
 385   const options::One_option* options =
 386     options::Command_line_options::options;
 387   bool no_more_options = false;
 388   int i = 0;
 389   while (i < argc)
 390     {
 391       if (argv[i][0] != '-' || no_more_options)
 392         {
 393           this->add_file(argv[i], false);
 394           ++i;
 395           continue;
 396         }
 397
 398       // Option starting with '-'.
 399       int dashes = 1;
 400       if (argv[i][1] == '-')
 401         {
 402           dashes = 2;
 403           if (argv[i][2] == '\0')
 404             {
 405               no_more_options = true;
 406               continue;
 407             }
 408         }
 409
 410       // Look for a long option match.
 411       char* opt = argv[i] + dashes;
 412       char first = opt[0];
 413       int skiparg = 0;
 414       char* arg = strchr(opt, '=');
 415       if (arg != NULL)
 416         *arg = '\0';
 417       else if (i + 1 < argc)
 418         {
 419           arg = argv[i + 1];
 420           skiparg = 1;
 421         }
 422
 423       int j;
 424       for (j = 0; j < options_size; ++j)
 425         {
 426           if (options[j].long_option != NULL
 427               && (dashes == 2
 428                   || (options[j].dash
 429                       != options::One_option::EXACTLY_TWO_DASHES))
 430               && first == options[j].long_option[0]
 431               && strcmp(opt, options[j].long_option) == 0)
 432             {
 433               if (options[j].special)
 434                 i += options[j].special(argc - 1, argv + i, opt, this);
 435               else
 436                 {
 437                   if (!options[j].takes_argument())
 438                     {
 439                       arg = NULL;
 440                       skiparg = 0;
 441                     }
 442                   else
 443                     {
 444                       if (arg == NULL)
 445                         this->usage(_("missing argument"), argv[i]);
 446                     }
 447                   this->apply_option(options[j], arg);
 448                   i += skiparg + 1;
 449                 }
 450               break;
 451             }
 452         }
 453       if (j < options_size)
 454         continue;
 455
 456       // If we saw two dashes, we need to see a long option.
 457       if (dashes == 2)
 458         this->usage(_("unknown option"), argv[i]);
 459
 460       // Look for a short option match.  There may be more than one
 461       // short option in a given argument.
 462       bool done = false;
 463       char* s = argv[i] + 1;
 464       ++i;
 465       while (*s != '\0' && !done)
 466         {
 467           char opt = *s;
 468           int j;
 469           for (j = 0; j < options_size; ++j)
 470             {
 471               if (options[j].short_option == opt)
 472                 {
 473                   if (options[j].special)
 474                     {
 475                       // Undo the argument skip done above.
 476                       --i;
 477                       i += options[j].special(argc - i, argv + i, s, this);
 478                       done = true;
 479                     }
 480                   else
 481                     {
 482                       arg = NULL;
 483                       if (options[j].takes_argument())
 484                         {
 485                           if (s[1] != '\0')
 486                             {
 487                               arg = s + 1;
 488                               done = true;
 489                             }
 490                           else if (i < argc)
 491                             {
 492                               arg = argv[i];
 493                               ++i;
 494                             }
 495                           else
 496                             this->usage(_("missing argument"), opt);
 497                         }
 498                       this->apply_option(options[j], arg);
 499                     }
 500                   break;
 501                 }
 502             }
 503
 504           if (j >= options_size)
 505             this->usage(_("unknown option"), *s);
 506
 507           ++s;
 508         }
 509     }
 510
 511   if (this->inputs_.in_group())
 512     {
 513       fprintf(stderr, _("%s: missing group end"), program_name);
 514       this->usage();
 515     }
 516
 517   // FIXME: We should only do this when configured in native mode.
 518   this->options_.add_to_search_path("/lib");
 519   this->options_.add_to_search_path("/usr/lib");
 520 }
 521
 522 // Apply a command line option.
 523
 524 void
 525 Command_line::apply_option(const options::One_option& opt,
 526                            const char* arg)
 527 {
 528   if (arg == NULL)
 529     {
 530       if (opt.general_noarg)
 531         (this->options_.*(opt.general_noarg))();
 532       else if (opt.dependent_noarg)
 533         (this->position_options_.*(opt.dependent_noarg))();
 534       else
 535         gold_unreachable();
 536     }
 537   else
 538     {
 539       if (opt.general_arg)
 540         (this->options_.*(opt.general_arg))(arg);
 541       else if (opt.dependent_arg)
 542         (this->position_options_.*(opt.dependent_arg))(arg);
 543       else
 544         gold_unreachable();
 545     }
 546 }
 547
 548 // Add an input file or library.
 549
 550 void
 551 Command_line::add_file(const char* name, bool is_lib)
 552 {
 553   Input_file_argument file(name, is_lib, this->position_options_);
 554   this->inputs_.add_file(file);
 555 }
 556
 557 // Handle the -l option, which requires special treatment.
 558
 559 int
 560 Command_line::process_l_option(int argc, char** argv, char* arg)
 561 {
 562   int ret;
 563   const char* libname;
 564   if (arg[1] != '\0')
 565     {
 566       ret = 1;
 567       libname = arg + 1;
 568     }
 569   else if (argc > 1)
 570     {
 571       ret = 2;
 572       libname = argv[argc + 1];
 573     }
 574   else
 575     this->usage(_("missing argument"), arg);
 576
 577   this->add_file(libname, true);
 578
 579   return ret;
 580 }
 581
 582 // Handle the --start-group option.
 583
 584 void
 585 Command_line::start_group(const char* arg)
 586 {
 587   if (this->inputs_.in_group())
 588     this->usage(_("may not nest groups"), arg);
 589   this->inputs_.start_group();
 590 }
 591
 592 // Handle the --end-group option.
 593
 594 void
 595 Command_line::end_group(const char* arg)
 596 {
 597   if (!this->inputs_.in_group())
 598     this->usage(_("group end without group start"), arg);
 599   this->inputs_.end_group();
 600 }
 601
 602 // Report a usage error.  */
 603
 604 void
 605 Command_line::usage()
 606 {
 607   fprintf(stderr,
 608           _("%s: use the --help option for usage information\n"),
 609           program_name);
 610   gold_exit(false);
 611 }
 612
 613 void
 614 Command_line::usage(const char* msg, const char *opt)
 615 {
 616   fprintf(stderr,
 617           _("%s: %s: %s\n"),
 618           program_name, opt, msg);
 619   this->usage();
 620 }
 621
 622 void
 623 Command_line::usage(const char* msg, char opt)
 624 {
 625   fprintf(stderr,
 626           _("%s: -%c: %s\n"),
 627           program_name, opt, msg);
 628   this->usage();
 629 }
 630
 631 } // End namespace gold.