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   GENERAL_ARG('\0', "sysroot", N_("Currently ignored"), NULL, TWO_DASHES,
 289               &General_options::ignore),
 290   POSDEP_NOARG('\0', "as-needed",
 291                N_("Only set DT_NEEDED for dynamic libs if used"),
 292                NULL, TWO_DASHES, &Position_dependent_options::set_as_needed),
 293   POSDEP_NOARG('\0', "no-as-needed",
 294                N_("Always DT_NEEDED for dynamic libs (default)"),
 295                NULL, TWO_DASHES, &Position_dependent_options::clear_as_needed),
 296   POSDEP_NOARG('\0', "whole-archive",
 297                N_("Include all archive contents"),
 298                NULL, TWO_DASHES,
 299                &Position_dependent_options::set_whole_archive),
 300   POSDEP_NOARG('\0', "no-whole-archive",
 301                N_("Include only needed archive contents"),
 302                NULL, TWO_DASHES,
 303                &Position_dependent_options::clear_whole_archive),
 304   SPECIAL('\0', "help", N_("Report usage information"), NULL,
 305           TWO_DASHES, &help)
 306 };
 307
 308 const int options::Command_line_options::options_size =
 309   sizeof (options) / sizeof (options[0]);
 310
 311 // The default values for the general options.
 312
 313 General_options::General_options()
 314   : export_dynamic_(false),
 315     dynamic_linker_(NULL),
 316     search_path_(),
 317     optimization_level_(0),
 318     output_file_name_("a.out"),
 319     is_relocatable_(false),
 320     create_eh_frame_hdr_(false),
 321     rpath_(),
 322     rpath_link_(),
 323     is_shared_(false),
 324     is_static_(false)
 325 {
 326 }
 327
 328 // The default values for the position dependent options.
 329
 330 Position_dependent_options::Position_dependent_options()
 331   : do_static_search_(false),
 332     as_needed_(false),
 333     include_whole_archive_(false)
 334 {
 335 }
 336
 337 // Input_arguments methods.
 338
 339 // Add a file to the list.
 340
 341 void
 342 Input_arguments::add_file(const Input_file_argument& file)
 343 {
 344   if (!this->in_group_)
 345     this->input_argument_list_.push_back(Input_argument(file));
 346   else
 347     {
 348       gold_assert(!this->input_argument_list_.empty());
 349       gold_assert(this->input_argument_list_.back().is_group());
 350       this->input_argument_list_.back().group()->add_file(file);
 351     }
 352 }
 353
 354 // Start a group.
 355
 356 void
 357 Input_arguments::start_group()
 358 {
 359   gold_assert(!this->in_group_);
 360   Input_file_group* group = new Input_file_group();
 361   this->input_argument_list_.push_back(Input_argument(group));
 362   this->in_group_ = true;
 363 }
 364
 365 // End a group.
 366
 367 void
 368 Input_arguments::end_group()
 369 {
 370   gold_assert(this->in_group_);
 371   this->in_group_ = false;
 372 }
 373
 374 // Command_line options.
 375
 376 Command_line::Command_line()
 377   : options_(), position_options_(), inputs_()
 378 {
 379 }
 380
 381 // Process the command line options.
 382
 383 void
 384 Command_line::process(int argc, char** argv)
 385 {
 386   const int options_size = options::Command_line_options::options_size;
 387   const options::One_option* options =
 388     options::Command_line_options::options;
 389   bool no_more_options = false;
 390   int i = 0;
 391   while (i < argc)
 392     {
 393       if (argv[i][0] != '-' || no_more_options)
 394         {
 395           this->add_file(argv[i], false);
 396           ++i;
 397           continue;
 398         }
 399
 400       // Option starting with '-'.
 401       int dashes = 1;
 402       if (argv[i][1] == '-')
 403         {
 404           dashes = 2;
 405           if (argv[i][2] == '\0')
 406             {
 407               no_more_options = true;
 408               continue;
 409             }
 410         }
 411
 412       // Look for a long option match.
 413       char* opt = argv[i] + dashes;
 414       char first = opt[0];
 415       int skiparg = 0;
 416       char* arg = strchr(opt, '=');
 417       if (arg != NULL)
 418         *arg = '\0';
 419       else if (i + 1 < argc)
 420         {
 421           arg = argv[i + 1];
 422           skiparg = 1;
 423         }
 424
 425       int j;
 426       for (j = 0; j < options_size; ++j)
 427         {
 428           if (options[j].long_option != NULL
 429               && (dashes == 2
 430                   || (options[j].dash
 431                       != options::One_option::EXACTLY_TWO_DASHES))
 432               && first == options[j].long_option[0]
 433               && strcmp(opt, options[j].long_option) == 0)
 434             {
 435               if (options[j].special)
 436                 i += options[j].special(argc - 1, argv + i, opt, this);
 437               else
 438                 {
 439                   if (!options[j].takes_argument())
 440                     {
 441                       arg = NULL;
 442                       skiparg = 0;
 443                     }
 444                   else
 445                     {
 446                       if (arg == NULL)
 447                         this->usage(_("missing argument"), argv[i]);
 448                     }
 449                   this->apply_option(options[j], arg);
 450                   i += skiparg + 1;
 451                 }
 452               break;
 453             }
 454         }
 455       if (j < options_size)
 456         continue;
 457
 458       // If we saw two dashes, we need to see a long option.
 459       if (dashes == 2)
 460         this->usage(_("unknown option"), argv[i]);
 461
 462       // Look for a short option match.  There may be more than one
 463       // short option in a given argument.
 464       bool done = false;
 465       char* s = argv[i] + 1;
 466       ++i;
 467       while (*s != '\0' && !done)
 468         {
 469           char opt = *s;
 470           int j;
 471           for (j = 0; j < options_size; ++j)
 472             {
 473               if (options[j].short_option == opt)
 474                 {
 475                   if (options[j].special)
 476                     {
 477                       // Undo the argument skip done above.
 478                       --i;
 479                       i += options[j].special(argc - i, argv + i, s, this);
 480                       done = true;
 481                     }
 482                   else
 483                     {
 484                       arg = NULL;
 485                       if (options[j].takes_argument())
 486                         {
 487                           if (s[1] != '\0')
 488                             {
 489                               arg = s + 1;
 490                               done = true;
 491                             }
 492                           else if (i < argc)
 493                             {
 494                               arg = argv[i];
 495                               ++i;
 496                             }
 497                           else
 498                             this->usage(_("missing argument"), opt);
 499                         }
 500                       this->apply_option(options[j], arg);
 501                     }
 502                   break;
 503                 }
 504             }
 505
 506           if (j >= options_size)
 507             this->usage(_("unknown option"), *s);
 508
 509           ++s;
 510         }
 511     }
 512
 513   if (this->inputs_.in_group())
 514     {
 515       fprintf(stderr, _("%s: missing group end"), program_name);
 516       this->usage();
 517     }
 518
 519   // FIXME: We should only do this when configured in native mode.
 520   this->options_.add_to_search_path("/lib");
 521   this->options_.add_to_search_path("/usr/lib");
 522 }
 523
 524 // Apply a command line option.
 525
 526 void
 527 Command_line::apply_option(const options::One_option& opt,
 528                            const char* arg)
 529 {
 530   if (arg == NULL)
 531     {
 532       if (opt.general_noarg)
 533         (this->options_.*(opt.general_noarg))();
 534       else if (opt.dependent_noarg)
 535         (this->position_options_.*(opt.dependent_noarg))();
 536       else
 537         gold_unreachable();
 538     }
 539   else
 540     {
 541       if (opt.general_arg)
 542         (this->options_.*(opt.general_arg))(arg);
 543       else if (opt.dependent_arg)
 544         (this->position_options_.*(opt.dependent_arg))(arg);
 545       else
 546         gold_unreachable();
 547     }
 548 }
 549
 550 // Add an input file or library.
 551
 552 void
 553 Command_line::add_file(const char* name, bool is_lib)
 554 {
 555   Input_file_argument file(name, is_lib, "", this->position_options_);
 556   this->inputs_.add_file(file);
 557 }
 558
 559 // Handle the -l option, which requires special treatment.
 560
 561 int
 562 Command_line::process_l_option(int argc, char** argv, char* arg)
 563 {
 564   int ret;
 565   const char* libname;
 566   if (arg[1] != '\0')
 567     {
 568       ret = 1;
 569       libname = arg + 1;
 570     }
 571   else if (argc > 1)
 572     {
 573       ret = 2;
 574       libname = argv[argc + 1];
 575     }
 576   else
 577     this->usage(_("missing argument"), arg);
 578
 579   this->add_file(libname, true);
 580
 581   return ret;
 582 }
 583
 584 // Handle the --start-group option.
 585
 586 void
 587 Command_line::start_group(const char* arg)
 588 {
 589   if (this->inputs_.in_group())
 590     this->usage(_("may not nest groups"), arg);
 591   this->inputs_.start_group();
 592 }
 593
 594 // Handle the --end-group option.
 595
 596 void
 597 Command_line::end_group(const char* arg)
 598 {
 599   if (!this->inputs_.in_group())
 600     this->usage(_("group end without group start"), arg);
 601   this->inputs_.end_group();
 602 }
 603
 604 // Report a usage error.  */
 605
 606 void
 607 Command_line::usage()
 608 {
 609   fprintf(stderr,
 610           _("%s: use the --help option for usage information\n"),
 611           program_name);
 612   gold_exit(false);
 613 }
 614
 615 void
 616 Command_line::usage(const char* msg, const char *opt)
 617 {
 618   fprintf(stderr,
 619           _("%s: %s: %s\n"),
 620           program_name, opt, msg);
 621   this->usage();
 622 }
 623
 624 void
 625 Command_line::usage(const char* msg, char opt)
 626 {
 627   fprintf(stderr,
 628           _("%s: -%c: %s\n"),
 629           program_name, opt, msg);
 630   this->usage();
 631 }
 632
 633 } // End namespace gold.