gold/options.cc

   1 // options.c -- handle command line options for gold
   2
   3 // Copyright 2006, 2007, 2008, 2009 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 <cerrno>
  26 #include <cstdlib>
  27 #include <cstring>
  28 #include <fstream>
  29 #include <vector>
  30 #include <iostream>
  31 #include <sys/stat.h>
  32 #include "filenames.h"
  33 #include "libiberty.h"
  34 #include "demangle.h"
  35 #include "../bfd/bfdver.h"
  36
  37 #include "debug.h"
  38 #include "script.h"
  39 #include "target-select.h"
  40 #include "options.h"
  41 #include "plugin.h"
  42
  43 namespace gold
  44 {
  45
  46 General_options
  47 Position_dependent_options::default_options_;
  48
  49 namespace options
  50 {
  51
  52 // This flag is TRUE if we should register the command-line options as they
  53 // are constructed.  It is set after contruction of the options within
  54 // class Position_dependent_options.
  55 static bool ready_to_register = false;
  56
  57 // This global variable is set up as General_options is constructed.
  58 static std::vector<const One_option*> registered_options;
  59
  60 // These are set up at the same time -- the variables that accept one
  61 // dash, two, or require -z.  A single variable may be in more than
  62 // one of thes data structures.
  63 typedef Unordered_map<std::string, One_option*> Option_map;
  64 static Option_map* long_options = NULL;
  65 static One_option* short_options[128];
  66
  67 void
  68 One_option::register_option()
  69 {
  70   if (!ready_to_register)
  71     return;
  72
  73   registered_options.push_back(this);
  74
  75   // We can't make long_options a static Option_map because we can't
  76   // guarantee that will be initialized before register_option() is
  77   // first called.
  78   if (long_options == NULL)
  79     long_options = new Option_map;
  80
  81   // TWO_DASHES means that two dashes are preferred, but one is ok too.
  82   if (!this->longname.empty())
  83     (*long_options)[this->longname] = this;
  84
  85   const int shortname_as_int = static_cast<int>(this->shortname);
  86   gold_assert(shortname_as_int >= 0 && shortname_as_int < 128);
  87   if (this->shortname != '\0')
  88     {
  89       gold_assert(short_options[shortname_as_int] == NULL);
  90       short_options[shortname_as_int] = this;
  91     }
  92 }
  93
  94 void
  95 One_option::print() const
  96 {
  97   bool comma = false;
  98   printf("  ");
  99   int len = 2;
 100   if (this->shortname != '\0')
 101     {
 102       len += printf("-%c", this->shortname);
 103       if (this->helparg)
 104         {
 105           // -z takes long-names only.
 106           gold_assert(this->dashes != DASH_Z);
 107           len += printf(" %s", gettext(this->helparg));
 108         }
 109       comma = true;
 110     }
 111   if (!this->longname.empty()
 112       && !(this->longname[0] == this->shortname
 113            && this->longname[1] == '\0'))
 114     {
 115       if (comma)
 116         len += printf(", ");
 117       switch (this->dashes)
 118         {
 119         case options::ONE_DASH: case options::EXACTLY_ONE_DASH:
 120           len += printf("-");
 121           break;
 122         case options::TWO_DASHES: case options::EXACTLY_TWO_DASHES:
 123           len += printf("--");
 124           break;
 125         case options::DASH_Z:
 126           len += printf("-z ");
 127           break;
 128         default:
 129           gold_unreachable();
 130         }
 131       len += printf("%s", this->longname.c_str());
 132       if (this->helparg)
 133         {
 134           // For most options, we print "--frob FOO".  But for -z
 135           // we print "-z frob=FOO".
 136           len += printf("%c%s", this->dashes == options::DASH_Z ? '=' : ' ',
 137                         gettext(this->helparg));
 138         }
 139     }
 140
 141   if (len >= 30)
 142     {
 143       printf("\n");
 144       len = 0;
 145     }
 146   for (; len < 30; ++len)
 147     std::putchar(' ');
 148
 149   // TODO: if we're boolean, add " (default)" when appropriate.
 150   printf("%s\n", gettext(this->helpstring));
 151 }
 152
 153 void
 154 help()
 155 {
 156   printf(_("Usage: %s [options] file...\nOptions:\n"), gold::program_name);
 157
 158   std::vector<const One_option*>::const_iterator it;
 159   for (it = registered_options.begin(); it != registered_options.end(); ++it)
 160     (*it)->print();
 161
 162   // config.guess and libtool.m4 look in ld --help output for the
 163   // string "supported targets".
 164   printf(_("%s: supported targets:"), gold::program_name);
 165   std::vector<const char*> supported_names;
 166   gold::supported_target_names(&supported_names);
 167   for (std::vector<const char*>::const_iterator p = supported_names.begin();
 168        p != supported_names.end();
 169        ++p)
 170     printf(" %s", *p);
 171   printf("\n");
 172
 173   // REPORT_BUGS_TO is defined in bfd/bfdver.h.
 174   const char* report = REPORT_BUGS_TO;
 175   if (*report != '\0')
 176     printf(_("Report bugs to %s\n"), report);
 177 }
 178
 179 // For bool, arg will be NULL (boolean options take no argument);
 180 // we always just set to true.
 181 void
 182 parse_bool(const char*, const char*, bool* retval)
 183 {
 184   *retval = true;
 185 }
 186
 187 void
 188 parse_uint(const char* option_name, const char* arg, int* retval)
 189 {
 190   char* endptr;
 191   *retval = strtol(arg, &endptr, 0);
 192   if (*endptr != '\0' || retval < 0)
 193     gold_fatal(_("%s: invalid option value (expected an integer): %s"),
 194                option_name, arg);
 195 }
 196
 197 void
 198 parse_uint64(const char* option_name, const char* arg, uint64_t *retval)
 199 {
 200   char* endptr;
 201   *retval = strtoull(arg, &endptr, 0);
 202   if (*endptr != '\0')
 203     gold_fatal(_("%s: invalid option value (expected an integer): %s"),
 204                option_name, arg);
 205 }
 206
 207 void
 208 parse_double(const char* option_name, const char* arg, double* retval)
 209 {
 210   char* endptr;
 211   *retval = strtod(arg, &endptr);
 212   if (*endptr != '\0')
 213     gold_fatal(_("%s: invalid option value "
 214                  "(expected a floating point number): %s"),
 215                option_name, arg);
 216 }
 217
 218 void
 219 parse_string(const char* option_name, const char* arg, const char** retval)
 220 {
 221   if (*arg == '\0')
 222     gold_fatal(_("%s: must take a non-empty argument"), option_name);
 223   *retval = arg;
 224 }
 225
 226 void
 227 parse_optional_string(const char*, const char* arg, const char** retval)
 228 {
 229   *retval = arg;
 230 }
 231
 232 void
 233 parse_dirlist(const char*, const char* arg, Dir_list* retval)
 234 {
 235   retval->push_back(Search_directory(arg, false));
 236 }
 237
 238 void
 239 parse_set(const char*, const char* arg, String_set* retval)
 240 {
 241   retval->insert(std::string(arg));
 242 }
 243
 244 void
 245 parse_choices(const char* option_name, const char* arg, const char** retval,
 246               const char* choices[], int num_choices)
 247 {
 248   for (int i = 0; i < num_choices; i++)
 249     if (strcmp(choices[i], arg) == 0)
 250       {
 251         *retval = arg;
 252         return;
 253       }
 254
 255   // If we get here, the user did not enter a valid choice, so we die.
 256   std::string choices_list;
 257   for (int i = 0; i < num_choices; i++)
 258     {
 259       choices_list += choices[i];
 260       if (i != num_choices - 1)
 261         choices_list += ", ";
 262     }
 263   gold_fatal(_("%s: must take one of the following arguments: %s"),
 264              option_name, choices_list.c_str());
 265 }
 266
 267 } // End namespace options.
 268
 269 // Define the handler for "special" options (set via DEFINE_special).
 270
 271 void
 272 General_options::parse_help(const char*, const char*, Command_line*)
 273 {
 274   options::help();
 275   ::exit(EXIT_SUCCESS);
 276 }
 277
 278 void
 279 General_options::parse_version(const char* opt, const char*, Command_line*)
 280 {
 281   gold::print_version(opt[0] == '-' && opt[1] == 'v');
 282   ::exit(EXIT_SUCCESS);
 283 }
 284
 285 void
 286 General_options::parse_V(const char*, const char*, Command_line*)
 287 {
 288   gold::print_version(true);
 289   this->printed_version_ = true;
 290   printf(_("  Supported targets:\n"));
 291   std::vector<const char*> supported_names;
 292   gold::supported_target_names(&supported_names);
 293   for (std::vector<const char*>::const_iterator p = supported_names.begin();
 294        p != supported_names.end();
 295        ++p)
 296     printf("   %s\n", *p);
 297 }
 298
 299 void
 300 General_options::parse_defsym(const char*, const char* arg,
 301                               Command_line* cmdline)
 302 {
 303   cmdline->script_options().define_symbol(arg);
 304 }
 305
 306 void
 307 General_options::parse_incremental_changed(const char*, const char*,
 308                                            Command_line*)
 309 {
 310   this->implicit_incremental_ = true;
 311   this->incremental_disposition_ = INCREMENTAL_CHANGED;
 312 }
 313
 314 void
 315 General_options::parse_incremental_unchanged(const char*, const char*,
 316                                              Command_line*)
 317 {
 318   this->implicit_incremental_ = true;
 319   this->incremental_disposition_ = INCREMENTAL_UNCHANGED;
 320 }
 321
 322 void
 323 General_options::parse_incremental_unknown(const char*, const char*,
 324                                            Command_line*)
 325 {
 326   this->implicit_incremental_ = true;
 327   this->incremental_disposition_ = INCREMENTAL_CHECK;
 328 }
 329
 330 void
 331 General_options::parse_library(const char*, const char* arg,
 332                                Command_line* cmdline)
 333 {
 334   Input_file_argument file(arg, true, "", false, *this);
 335   cmdline->inputs().add_file(file);
 336 }
 337
 338 #ifdef ENABLE_PLUGINS
 339 void
 340 General_options::parse_plugin(const char*, const char* arg,
 341                               Command_line*)
 342 {
 343   this->add_plugin(arg);
 344 }
 345
 346 // Parse --plugin-opt.
 347
 348 void
 349 General_options::parse_plugin_opt(const char*, const char* arg,
 350                                   Command_line*)
 351 {
 352   this->add_plugin_option(arg);
 353 }
 354 #endif // ENABLE_PLUGINS
 355
 356 void
 357 General_options::parse_R(const char* option, const char* arg,
 358                          Command_line* cmdline)
 359 {
 360   struct stat s;
 361   if (::stat(arg, &s) != 0 || S_ISDIR(s.st_mode))
 362     this->add_to_rpath(arg);
 363   else
 364     this->parse_just_symbols(option, arg, cmdline);
 365 }
 366
 367 void
 368 General_options::parse_just_symbols(const char*, const char* arg,
 369                                     Command_line* cmdline)
 370 {
 371   Input_file_argument file(arg, false, "", true, *this);
 372   cmdline->inputs().add_file(file);
 373 }
 374
 375 void
 376 General_options::parse_static(const char*, const char*, Command_line*)
 377 {
 378   this->set_static(true);
 379 }
 380
 381 void
 382 General_options::parse_script(const char*, const char* arg,
 383                               Command_line* cmdline)
 384 {
 385   if (!read_commandline_script(arg, cmdline))
 386     gold::gold_fatal(_("unable to parse script file %s"), arg);
 387 }
 388
 389 void
 390 General_options::parse_version_script(const char*, const char* arg,
 391                                       Command_line* cmdline)
 392 {
 393   if (!read_version_script(arg, cmdline))
 394     gold::gold_fatal(_("unable to parse version script file %s"), arg);
 395 }
 396
 397 void
 398 General_options::parse_dynamic_list(const char*, const char* arg,
 399                                     Command_line* cmdline)
 400 {
 401   if (!read_dynamic_list(arg, cmdline, &this->dynamic_list_))
 402     gold::gold_fatal(_("unable to parse dynamic-list script file %s"), arg);
 403 }
 404
 405 void
 406 General_options::parse_start_group(const char*, const char*,
 407                                    Command_line* cmdline)
 408 {
 409   cmdline->inputs().start_group();
 410 }
 411
 412 void
 413 General_options::parse_end_group(const char*, const char*,
 414                                  Command_line* cmdline)
 415 {
 416   cmdline->inputs().end_group();
 417 }
 418
 419 // The function add_excluded_libs() in ld/ldlang.c of GNU ld breaks up a list
 420 // of names seperated by commas or colons and puts them in a linked list.
 421 // We implement the same parsing of names here but store names in an unordered
 422 // map to speed up searching of names.
 423
 424 void
 425 General_options::parse_exclude_libs(const char*, const char* arg,
 426                                     Command_line*)
 427 {
 428   const char *p = arg;
 429
 430   while (*p != '\0')
 431     {
 432       size_t length = strcspn(p, ",:");
 433       this->excluded_libs_.insert(std::string(p, length));
 434       p += (p[length] ? length + 1 : length);
 435     }
 436 }
 437
 438 // The checking logic is based on the function check_excluded_libs() in
 439 // ld/ldlang.c of GNU ld but our implementation is different because we use
 440 // an unordered map instead of a linked list, which is what GNU ld uses.  GNU
 441 // ld searches sequentially in the excluded libs list.  For a given archive,
 442 // a match is found if the archive's name matches exactly one of the list
 443 // entry or if the archive's name is of the form FOO.a and FOO matches exactly
 444 // one of the list entry.  An entry "ALL" in the list is considered as a
 445 // wild-card and matches any given name.
 446
 447 bool
 448 General_options::check_excluded_libs (const std::string &name) const
 449 {
 450   Unordered_set<std::string>::const_iterator p;
 451
 452   // Exit early for the most common case.
 453   if (excluded_libs_.empty())
 454     return false;
 455
 456   // If we see "ALL", all archives are excluded from automatic export.
 457   p = excluded_libs_.find(std::string("ALL"));
 458   if (p != excluded_libs_.end())
 459     return true;
 460
 461   // First strip off any directories in name.
 462   const char *basename = lbasename(name.c_str());
 463
 464   // Try finding an exact match.
 465   p = excluded_libs_.find(std::string(basename));
 466   if (p != excluded_libs_.end())
 467     return true;
 468
 469   // Try matching NAME without ".a" at the end.
 470   size_t length = strlen(basename);
 471   if ((length >= 2)
 472       && (basename[length - 2] == '.')
 473       && (basename[length - 1] == 'a'))
 474     {
 475       p = excluded_libs_.find(std::string(basename, length - 2));
 476       if (p != excluded_libs_.end())
 477         return true;
 478     }
 479
 480   return false;
 481 }
 482
 483 // Recognize input and output target names.  The GNU linker accepts
 484 // these with --format and --oformat.  This code is intended to be
 485 // minimally compatible.  In practice for an ELF target this would be
 486 // the same target as the input files; that name always start with
 487 // "elf".  Non-ELF targets would be "srec", "symbolsrec", "tekhex",
 488 // "binary", "ihex".
 489
 490 General_options::Object_format
 491 General_options::string_to_object_format(const char* arg)
 492 {
 493   if (strncmp(arg, "elf", 3) == 0)
 494     return gold::General_options::OBJECT_FORMAT_ELF;
 495   else if (strcmp(arg, "binary") == 0)
 496     return gold::General_options::OBJECT_FORMAT_BINARY;
 497   else
 498     {
 499       gold::gold_error(_("format '%s' not supported; treating as elf "
 500                          "(supported formats: elf, binary)"),
 501                        arg);
 502       return gold::General_options::OBJECT_FORMAT_ELF;
 503     }
 504 }
 505
 506 } // End namespace gold.
 507
 508 namespace
 509 {
 510
 511 void
 512 usage()
 513 {
 514   fprintf(stderr,
 515           _("%s: use the --help option for usage information\n"),
 516           gold::program_name);
 517   ::exit(EXIT_FAILURE);
 518 }
 519
 520 void
 521 usage(const char* msg, const char *opt)
 522 {
 523   fprintf(stderr,
 524           _("%s: %s: %s\n"),
 525           gold::program_name, opt, msg);
 526   usage();
 527 }
 528
 529 // If the default sysroot is relocatable, try relocating it based on
 530 // the prefix FROM.
 531
 532 static char*
 533 get_relative_sysroot(const char* from)
 534 {
 535   char* path = make_relative_prefix(gold::program_name, from,
 536                                     TARGET_SYSTEM_ROOT);
 537   if (path != NULL)
 538     {
 539       struct stat s;
 540       if (::stat(path, &s) == 0 && S_ISDIR(s.st_mode))
 541         return path;
 542       free(path);
 543     }
 544
 545   return NULL;
 546 }
 547
 548 // Return the default sysroot.  This is set by the --with-sysroot
 549 // option to configure.  Note we do not free the return value of
 550 // get_relative_sysroot, which is a small memory leak, but is
 551 // necessary since we store this pointer directly in General_options.
 552
 553 static const char*
 554 get_default_sysroot()
 555 {
 556   const char* sysroot = TARGET_SYSTEM_ROOT;
 557   if (*sysroot == '\0')
 558     return NULL;
 559
 560   if (TARGET_SYSTEM_ROOT_RELOCATABLE)
 561     {
 562       char* path = get_relative_sysroot(BINDIR);
 563       if (path == NULL)
 564         path = get_relative_sysroot(TOOLBINDIR);
 565       if (path != NULL)
 566         return path;
 567     }
 568
 569   return sysroot;
 570 }
 571
 572 // Parse a long option.  Such options have the form
 573 // <-|--><option>[=arg].  If "=arg" is not present but the option
 574 // takes an argument, the next word is taken to the be the argument.
 575 // If equals_only is set, then only the <option>=<arg> form is
 576 // accepted, not the <option><space><arg> form.  Returns a One_option
 577 // struct or NULL if argv[i] cannot be parsed as a long option.  In
 578 // the not-NULL case, *arg is set to the option's argument (NULL if
 579 // the option takes no argument), and *i is advanced past this option.
 580 // NOTE: it is safe for argv and arg to point to the same place.
 581 gold::options::One_option*
 582 parse_long_option(int argc, const char** argv, bool equals_only,
 583                   const char** arg, int* i)
 584 {
 585   const char* const this_argv = argv[*i];
 586
 587   const char* equals = strchr(this_argv, '=');
 588   const char* option_start = this_argv + strspn(this_argv, "-");
 589   std::string option(option_start,
 590                      equals ? equals - option_start : strlen(option_start));
 591
 592   gold::options::Option_map::iterator it
 593       = gold::options::long_options->find(option);
 594   if (it == gold::options::long_options->end())
 595     return NULL;
 596
 597   gold::options::One_option* retval = it->second;
 598
 599   // If the dash-count doesn't match, we fail.
 600   if (this_argv[0] != '-')  // no dashes at all: had better be "-z <longopt>"
 601     {
 602       if (retval->dashes != gold::options::DASH_Z)
 603         return NULL;
 604     }
 605   else if (this_argv[1] != '-')   // one dash
 606     {
 607       if (retval->dashes != gold::options::ONE_DASH
 608           && retval->dashes != gold::options::EXACTLY_ONE_DASH
 609           && retval->dashes != gold::options::TWO_DASHES)
 610         return NULL;
 611     }
 612   else                            // two dashes (or more!)
 613     {
 614       if (retval->dashes != gold::options::TWO_DASHES
 615           && retval->dashes != gold::options::EXACTLY_TWO_DASHES
 616           && retval->dashes != gold::options::ONE_DASH)
 617         return NULL;
 618     }
 619
 620   // Now that we know the option is good (or else bad in a way that
 621   // will cause us to die), increment i to point past this argv.
 622   ++(*i);
 623
 624   // Figure out the option's argument, if any.
 625   if (!retval->takes_argument())
 626     {
 627       if (equals)
 628         usage(_("unexpected argument"), this_argv);
 629       else
 630         *arg = NULL;
 631     }
 632   else
 633     {
 634       if (equals)
 635         *arg = equals + 1;
 636       else if (retval->takes_optional_argument())
 637         *arg = retval->default_value;
 638       else if (*i < argc && !equals_only)
 639         *arg = argv[(*i)++];
 640       else
 641         usage(_("missing argument"), this_argv);
 642     }
 643
 644   return retval;
 645 }
 646
 647 // Parse a short option.  Such options have the form -<option>[arg].
 648 // If "arg" is not present but the option takes an argument, the next
 649 // word is taken to the be the argument.  If the option does not take
 650 // an argument, it may be followed by another short option.  Returns a
 651 // One_option struct or NULL if argv[i] cannot be parsed as a short
 652 // option.  In the not-NULL case, *arg is set to the option's argument
 653 // (NULL if the option takes no argument), and *i is advanced past
 654 // this option.  This function keeps *i the same if we parsed a short
 655 // option that does not take an argument, that looks to be followed by
 656 // another short option in the same word.
 657 gold::options::One_option*
 658 parse_short_option(int argc, const char** argv, int pos_in_argv_i,
 659                    const char** arg, int* i)
 660 {
 661   const char* const this_argv = argv[*i];
 662
 663   if (this_argv[0] != '-')
 664     return NULL;
 665
 666   // We handle -z as a special case.
 667   static gold::options::One_option dash_z("", gold::options::DASH_Z,
 668                                           'z', "", NULL, "Z-OPTION", false,
 669                                           NULL);
 670   gold::options::One_option* retval = NULL;
 671   if (this_argv[pos_in_argv_i] == 'z')
 672     retval = &dash_z;
 673   else
 674     {
 675       const int char_as_int = static_cast<int>(this_argv[pos_in_argv_i]);
 676       if (char_as_int > 0 && char_as_int < 128)
 677         retval = gold::options::short_options[char_as_int];
 678     }
 679
 680   if (retval == NULL)
 681     return NULL;
 682
 683   // Figure out the option's argument, if any.
 684   if (!retval->takes_argument())
 685     {
 686       *arg = NULL;
 687       // We only advance past this argument if it's the only one in argv.
 688       if (this_argv[pos_in_argv_i + 1] == '\0')
 689         ++(*i);
 690     }
 691   else
 692     {
 693       // If we take an argument, we'll eat up this entire argv entry.
 694       ++(*i);
 695       if (this_argv[pos_in_argv_i + 1] != '\0')
 696         *arg = this_argv + pos_in_argv_i + 1;
 697       else if (retval->takes_optional_argument())
 698         *arg = retval->default_value;
 699       else if (*i < argc)
 700         *arg = argv[(*i)++];
 701       else
 702         usage(_("missing argument"), this_argv);
 703     }
 704
 705   // If we're a -z option, we need to parse our argument as a
 706   // long-option, e.g. "-z stacksize=8192".
 707   if (retval == &dash_z)
 708     {
 709       int dummy_i = 0;
 710       const char* dash_z_arg = *arg;
 711       retval = parse_long_option(1, arg, true, arg, &dummy_i);
 712       if (retval == NULL)
 713         usage(_("unknown -z option"), dash_z_arg);
 714     }
 715
 716   return retval;
 717 }
 718
 719 } // End anonymous namespace.
 720
 721 namespace gold
 722 {
 723
 724 General_options::General_options()
 725   : printed_version_(false),
 726     execstack_status_(General_options::EXECSTACK_FROM_INPUT), static_(false),
 727     do_demangle_(false), plugins_(),
 728     incremental_disposition_(INCREMENTAL_CHECK), implicit_incremental_(false)
 729 {
 730   // Turn off option registration once construction is complete.
 731   gold::options::ready_to_register = false;
 732 }
 733
 734 General_options::Object_format
 735 General_options::format_enum() const
 736 {
 737   return General_options::string_to_object_format(this->format());
 738 }
 739
 740 General_options::Object_format
 741 General_options::oformat_enum() const
 742 {
 743   return General_options::string_to_object_format(this->oformat());
 744 }
 745
 746 // Add the sysroot, if any, to the search paths.
 747
 748 void
 749 General_options::add_sysroot()
 750 {
 751   if (this->sysroot() == NULL || this->sysroot()[0] == '\0')
 752     {
 753       this->set_sysroot(get_default_sysroot());
 754       if (this->sysroot() == NULL || this->sysroot()[0] == '\0')
 755         return;
 756     }
 757
 758   char* canonical_sysroot = lrealpath(this->sysroot());
 759
 760   for (Dir_list::iterator p = this->library_path_.value.begin();
 761        p != this->library_path_.value.end();
 762        ++p)
 763     p->add_sysroot(this->sysroot(), canonical_sysroot);
 764
 765   free(canonical_sysroot);
 766 }
 767
 768 // Return whether FILENAME is in a system directory.
 769
 770 bool
 771 General_options::is_in_system_directory(const std::string& filename) const
 772 {
 773   for (Dir_list::const_iterator p = this->library_path_.value.begin();
 774        p != this->library_path_.value.end();
 775        ++p)
 776     {
 777       // We use a straight string comparison rather than calling
 778       // FILENAME_CMP because we are only interested in the cases
 779       // where we found the file in a system directory, which means
 780       // that we used the directory name as a prefix for a -L search.
 781       if (p->is_system_directory()
 782           && filename.compare(0, p->name().size(), p->name()) == 0)
 783         return true;
 784     }
 785   return false;
 786 }
 787
 788 // Add a plugin to the list of plugins.
 789
 790 void
 791 General_options::add_plugin(const char* filename)
 792 {
 793   if (this->plugins_ == NULL)
 794     this->plugins_ = new Plugin_manager(*this);
 795   this->plugins_->add_plugin(filename);
 796 }
 797
 798 // Add a plugin option to a plugin.
 799
 800 void
 801 General_options::add_plugin_option(const char* arg)
 802 {
 803   if (this->plugins_ == NULL)
 804     gold_fatal("--plugin-opt requires --plugin.");
 805   this->plugins_->add_plugin_option(arg);
 806 }
 807
 808 // Set up variables and other state that isn't set up automatically by
 809 // the parse routine, and ensure options don't contradict each other
 810 // and are otherwise kosher.
 811
 812 void
 813 General_options::finalize()
 814 {
 815   // Normalize the strip modifiers.  They have a total order:
 816   // strip_all > strip_debug > strip_non_line > strip_debug_gdb.
 817   // If one is true, set all beneath it to true as well.
 818   if (this->strip_all())
 819     this->set_strip_debug(true);
 820   if (this->strip_debug())
 821     this->set_strip_debug_non_line(true);
 822   if (this->strip_debug_non_line())
 823     this->set_strip_debug_gdb(true);
 824
 825   if (this->Bshareable())
 826     this->set_shared(true);
 827
 828   // If the user specifies both -s and -r, convert the -s to -S.
 829   // -r requires us to keep externally visible symbols!
 830   if (this->strip_all() && this->relocatable())
 831     {
 832       this->set_strip_all(false);
 833       gold_assert(this->strip_debug());
 834     }
 835
 836   // For us, -dc and -dp are synonyms for --define-common.
 837   if (this->dc())
 838     this->set_define_common(true);
 839   if (this->dp())
 840     this->set_define_common(true);
 841
 842   // We also set --define-common if we're not relocatable, as long as
 843   // the user didn't explicitly ask for something different.
 844   if (!this->user_set_define_common())
 845     this->set_define_common(!this->relocatable());
 846
 847   // execstack_status_ is a three-state variable; update it based on
 848   // -z [no]execstack.
 849   if (this->execstack())
 850     this->set_execstack_status(EXECSTACK_YES);
 851   else if (this->noexecstack())
 852     this->set_execstack_status(EXECSTACK_NO);
 853
 854   // Handle the optional argument for --demangle.
 855   if (this->user_set_demangle())
 856     {
 857       this->set_do_demangle(true);
 858       const char* style = this->demangle();
 859       if (*style != '\0')
 860         {
 861           enum demangling_styles style_code;
 862
 863           style_code = cplus_demangle_name_to_style(style);
 864           if (style_code == unknown_demangling)
 865             gold_fatal("unknown demangling style '%s'", style);
 866           cplus_demangle_set_style(style_code);
 867         }
 868     }
 869   else if (this->user_set_no_demangle())
 870     this->set_do_demangle(false);
 871   else
 872     {
 873       // Testing COLLECT_NO_DEMANGLE makes our default demangling
 874       // behaviour identical to that of gcc's linker wrapper.
 875       this->set_do_demangle(getenv("COLLECT_NO_DEMANGLE") == NULL);
 876     }
 877
 878   // -M is equivalent to "-Map -".
 879   if (this->print_map() && !this->user_set_Map())
 880     {
 881       this->set_Map("-");
 882       this->set_user_set_Map();
 883     }
 884
 885   // Using -n or -N implies -static.
 886   if (this->nmagic() || this->omagic())
 887     this->set_static(true);
 888
 889   // If --thread_count is specified, it applies to
 890   // --thread-count-{initial,middle,final}, though it doesn't override
 891   // them.
 892   if (this->thread_count() > 0 && this->thread_count_initial() == 0)
 893     this->set_thread_count_initial(this->thread_count());
 894   if (this->thread_count() > 0 && this->thread_count_middle() == 0)
 895     this->set_thread_count_middle(this->thread_count());
 896   if (this->thread_count() > 0 && this->thread_count_final() == 0)
 897     this->set_thread_count_final(this->thread_count());
 898
 899   // Let's warn if you set the thread-count but we're going to ignore it.
 900 #ifndef ENABLE_THREADS
 901   if (this->threads())
 902     {
 903       gold_warning(_("ignoring --threads: "
 904                      "%s was compiled without thread support"),
 905                    program_name);
 906       this->set_threads(false);
 907     }
 908   if (this->thread_count() > 0 || this->thread_count_initial() > 0
 909       || this->thread_count_middle() > 0 || this->thread_count_final() > 0)
 910     gold_warning(_("ignoring --thread-count: "
 911                    "%s was compiled without thread support"),
 912                  program_name);
 913 #endif
 914
 915   if (this->user_set_Y())
 916     {
 917       std::string s = this->Y();
 918       if (s.compare(0, 2, "P,") == 0)
 919         s.erase(0, 2);
 920
 921       size_t pos = 0;
 922       size_t next_pos;
 923       do
 924         {
 925           next_pos = s.find(':', pos);
 926           size_t len = (next_pos == std::string::npos
 927                         ? next_pos
 928                         : next_pos - pos);
 929           if (len != 0)
 930             this->add_to_library_path_with_sysroot(s.substr(pos, len).c_str());
 931           pos = next_pos + 1;
 932         }
 933       while (next_pos != std::string::npos);
 934     }
 935   else
 936     {
 937       // Even if they don't specify it, we add -L /lib and -L /usr/lib.
 938       // FIXME: We should only do this when configured in native mode.
 939       this->add_to_library_path_with_sysroot("/lib");
 940       this->add_to_library_path_with_sysroot("/usr/lib");
 941     }
 942
 943   // Parse the contents of -retain-symbols-file into a set.
 944   if (this->retain_symbols_file())
 945     {
 946       std::ifstream in;
 947       in.open(this->retain_symbols_file());
 948       if (!in)
 949         gold_fatal(_("unable to open -retain-symbols-file file %s: %s"),
 950                    this->retain_symbols_file(), strerror(errno));
 951       std::string line;
 952       std::getline(in, line);   // this chops off the trailing \n, if any
 953       while (in)
 954         {
 955           if (!line.empty() && line[line.length() - 1] == '\r')   // Windows
 956             line.resize(line.length() - 1);
 957           this->symbols_to_retain_.insert(line);
 958           std::getline(in, line);
 959         }
 960     }
 961
 962   if (this->shared() && !this->user_set_allow_shlib_undefined())
 963     this->set_allow_shlib_undefined(true);
 964
 965   // Normalize library_path() by adding the sysroot to all directories
 966   // in the path, as appropriate.
 967   this->add_sysroot();
 968
 969   // Now that we've normalized the options, check for contradictory ones.
 970   if (this->shared() && this->is_static())
 971     gold_fatal(_("-shared and -static are incompatible"));
 972
 973   if (this->shared() && this->relocatable())
 974     gold_fatal(_("-shared and -r are incompatible"));
 975
 976   // TODO: implement support for -retain-symbols-file with -r, if needed.
 977   if (this->relocatable() && this->retain_symbols_file())
 978     gold_fatal(_("-retain-symbols-file does not yet work with -r"));
 979
 980   if (this->oformat_enum() != General_options::OBJECT_FORMAT_ELF
 981       && (this->shared() || this->relocatable()))
 982     gold_fatal(_("binary output format not compatible with -shared or -r"));
 983
 984   if (this->user_set_hash_bucket_empty_fraction()
 985       && (this->hash_bucket_empty_fraction() < 0.0
 986           || this->hash_bucket_empty_fraction() >= 1.0))
 987     gold_fatal(_("--hash-bucket-empty-fraction value %g out of range "
 988                  "[0.0, 1.0)"),
 989                this->hash_bucket_empty_fraction());
 990
 991   if (this->implicit_incremental_ && !this->incremental())
 992     gold_fatal(_("Options --incremental-changed, --incremental-unchanged, "
 993                  "--incremental-unknown require the use of --incremental"));
 994
 995   // FIXME: we can/should be doing a lot more sanity checking here.
 996 }
 997
 998 // Search_directory methods.
 999
1000 // This is called if we have a sysroot.  Apply the sysroot if
1001 // appropriate.  Record whether the directory is in the sysroot.
1002
1003 void
1004 Search_directory::add_sysroot(const char* sysroot,
1005                               const char* canonical_sysroot)
1006 {
1007   gold_assert(*sysroot != '\0');
1008   if (this->put_in_sysroot_)
1009     {
1010       if (!IS_DIR_SEPARATOR(this->name_[0])
1011           && !IS_DIR_SEPARATOR(sysroot[strlen(sysroot) - 1]))
1012         this->name_ = '/' + this->name_;
1013       this->name_ = sysroot + this->name_;
1014       this->is_in_sysroot_ = true;
1015     }
1016   else
1017     {
1018       // Check whether this entry is in the sysroot.  To do this
1019       // correctly, we need to use canonical names.  Otherwise we will
1020       // get confused by the ../../.. paths that gcc tends to use.
1021       char* canonical_name = lrealpath(this->name_.c_str());
1022       int canonical_name_len = strlen(canonical_name);
1023       int canonical_sysroot_len = strlen(canonical_sysroot);
1024       if (canonical_name_len > canonical_sysroot_len
1025           && IS_DIR_SEPARATOR(canonical_name[canonical_sysroot_len]))
1026         {
1027           canonical_name[canonical_sysroot_len] = '\0';
1028           if (FILENAME_CMP(canonical_name, canonical_sysroot) == 0)
1029             this->is_in_sysroot_ = true;
1030         }
1031       free(canonical_name);
1032     }
1033 }
1034
1035 // Input_arguments methods.
1036
1037 // Add a file to the list.
1038
1039 void
1040 Input_arguments::add_file(const Input_file_argument& file)
1041 {
1042   if (!this->in_group_)
1043     this->input_argument_list_.push_back(Input_argument(file));
1044   else
1045     {
1046       gold_assert(!this->input_argument_list_.empty());
1047       gold_assert(this->input_argument_list_.back().is_group());
1048       this->input_argument_list_.back().group()->add_file(file);
1049     }
1050 }
1051
1052 // Start a group.
1053
1054 void
1055 Input_arguments::start_group()
1056 {
1057   if (this->in_group_)
1058     gold_fatal(_("May not nest groups"));
1059   Input_file_group* group = new Input_file_group();
1060   this->input_argument_list_.push_back(Input_argument(group));
1061   this->in_group_ = true;
1062 }
1063
1064 // End a group.
1065
1066 void
1067 Input_arguments::end_group()
1068 {
1069   if (!this->in_group_)
1070     gold_fatal(_("Group end without group start"));
1071   this->in_group_ = false;
1072 }
1073
1074 // Command_line options.
1075
1076 Command_line::Command_line()
1077 {
1078 }
1079
1080 // Pre_options is the hook that sets the ready_to_register flag.
1081
1082 Command_line::Pre_options::Pre_options()
1083 {
1084   gold::options::ready_to_register = true;
1085 }
1086
1087 // Process the command line options.  For process_one_option, i is the
1088 // index of argv to process next, and must be an option (that is,
1089 // start with a dash).  The return value is the index of the next
1090 // option to process (i+1 or i+2, or argc to indicate processing is
1091 // done).  no_more_options is set to true if (and when) "--" is seen
1092 // as an option.
1093
1094 int
1095 Command_line::process_one_option(int argc, const char** argv, int i,
1096                                  bool* no_more_options)
1097 {
1098   gold_assert(argv[i][0] == '-' && !(*no_more_options));
1099
1100   // If we are reading "--", then just set no_more_options and return.
1101   if (argv[i][1] == '-' && argv[i][2] == '\0')
1102     {
1103       *no_more_options = true;
1104       return i + 1;
1105     }
1106
1107   int new_i = i;
1108   options::One_option* option = NULL;
1109   const char* arg = NULL;
1110
1111   // First, try to process argv as a long option.
1112   option = parse_long_option(argc, argv, false, &arg, &new_i);
1113   if (option)
1114     {
1115       option->reader->parse_to_value(argv[i], arg, this, &this->options_);
1116       return new_i;
1117     }
1118
1119   // Now, try to process argv as a short option.  Since several short
1120   // options can be combined in one argv, we may have to parse a lot
1121   // until we're done reading this argv.
1122   int pos_in_argv_i = 1;
1123   while (new_i == i)
1124     {
1125       option = parse_short_option(argc, argv, pos_in_argv_i, &arg, &new_i);
1126       if (!option)
1127         break;
1128       option->reader->parse_to_value(argv[i], arg, this, &this->options_);
1129       ++pos_in_argv_i;
1130     }
1131   if (option)
1132     return new_i;
1133
1134   // I guess it's neither a long option nor a short option.
1135   usage(_("unknown option"), argv[i]);
1136   return argc;
1137 }
1138
1139
1140 void
1141 Command_line::process(int argc, const char** argv)
1142 {
1143   bool no_more_options = false;
1144   int i = 0;
1145   while (i < argc)
1146     {
1147       this->position_options_.copy_from_options(this->options());
1148       if (no_more_options || argv[i][0] != '-')
1149         {
1150           Input_file_argument file(argv[i], false, "", false,
1151                                    this->position_options_);
1152           this->inputs_.add_file(file);
1153           ++i;
1154         }
1155       else
1156         i = process_one_option(argc, argv, i, &no_more_options);
1157     }
1158
1159   if (this->inputs_.in_group())
1160     {
1161       fprintf(stderr, _("%s: missing group end\n"), program_name);
1162       usage();
1163     }
1164
1165   // Normalize the options and ensure they don't contradict each other.
1166   this->options_.finalize();
1167 }
1168
1169 } // End namespace gold.