gold/options.cc

   1 // options.c -- handle command line options for gold
   2
   3 // Copyright 2006, 2007, 2008, 2009, 2010 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 construction 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 these 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_int(const char* option_name, const char* arg, int* retval)
 199 {
 200   char* endptr;
 201   *retval = strtol(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_uint64(const char* option_name, const char* arg, uint64_t* retval)
 209 {
 210   char* endptr;
 211   *retval = strtoull(arg, &endptr, 0);
 212   if (*endptr != '\0')
 213     gold_fatal(_("%s: invalid option value (expected an integer): %s"),
 214                option_name, arg);
 215 }
 216
 217 void
 218 parse_double(const char* option_name, const char* arg, double* retval)
 219 {
 220   char* endptr;
 221   *retval = strtod(arg, &endptr);
 222   if (*endptr != '\0')
 223     gold_fatal(_("%s: invalid option value "
 224                  "(expected a floating point number): %s"),
 225                option_name, arg);
 226 }
 227
 228 void
 229 parse_string(const char* option_name, const char* arg, const char** retval)
 230 {
 231   if (*arg == '\0')
 232     gold_fatal(_("%s: must take a non-empty argument"), option_name);
 233   *retval = arg;
 234 }
 235
 236 void
 237 parse_optional_string(const char*, const char* arg, const char** retval)
 238 {
 239   *retval = arg;
 240 }
 241
 242 void
 243 parse_dirlist(const char*, const char* arg, Dir_list* retval)
 244 {
 245   retval->push_back(Search_directory(arg, false));
 246 }
 247
 248 void
 249 parse_set(const char*, const char* arg, String_set* retval)
 250 {
 251   retval->insert(std::string(arg));
 252 }
 253
 254 void
 255 parse_choices(const char* option_name, const char* arg, const char** retval,
 256               const char* choices[], int num_choices)
 257 {
 258   for (int i = 0; i < num_choices; i++)
 259     if (strcmp(choices[i], arg) == 0)
 260       {
 261         *retval = arg;
 262         return;
 263       }
 264
 265   // If we get here, the user did not enter a valid choice, so we die.
 266   std::string choices_list;
 267   for (int i = 0; i < num_choices; i++)
 268     {
 269       choices_list += choices[i];
 270       if (i != num_choices - 1)
 271         choices_list += ", ";
 272     }
 273   gold_fatal(_("%s: must take one of the following arguments: %s"),
 274              option_name, choices_list.c_str());
 275 }
 276
 277 } // End namespace options.
 278
 279 // Define the handler for "special" options (set via DEFINE_special).
 280
 281 void
 282 General_options::parse_help(const char*, const char*, Command_line*)
 283 {
 284   options::help();
 285   ::exit(EXIT_SUCCESS);
 286 }
 287
 288 void
 289 General_options::parse_version(const char* opt, const char*, Command_line*)
 290 {
 291   bool print_short = (opt[0] == '-' && opt[1] == 'v');
 292   gold::print_version(print_short);
 293   this->printed_version_ = true;
 294   if (!print_short)
 295     ::exit(EXIT_SUCCESS);
 296 }
 297
 298 void
 299 General_options::parse_V(const char*, const char*, Command_line*)
 300 {
 301   gold::print_version(true);
 302   this->printed_version_ = true;
 303   printf(_("  Supported targets:\n"));
 304   std::vector<const char*> supported_names;
 305   gold::supported_target_names(&supported_names);
 306   for (std::vector<const char*>::const_iterator p = supported_names.begin();
 307        p != supported_names.end();
 308        ++p)
 309     printf("   %s\n", *p);
 310 }
 311
 312 void
 313 General_options::parse_defsym(const char*, const char* arg,
 314                               Command_line* cmdline)
 315 {
 316   cmdline->script_options().define_symbol(arg);
 317 }
 318
 319 void
 320 General_options::parse_incremental(const char*, const char*,
 321                                    Command_line*)
 322 {
 323   this->incremental_mode_ = INCREMENTAL_AUTO;
 324 }
 325
 326 void
 327 General_options::parse_no_incremental(const char*, const char*,
 328                                       Command_line*)
 329 {
 330   this->incremental_mode_ = INCREMENTAL_OFF;
 331 }
 332
 333 void
 334 General_options::parse_incremental_full(const char*, const char*,
 335                                         Command_line*)
 336 {
 337   this->incremental_mode_ = INCREMENTAL_FULL;
 338 }
 339
 340 void
 341 General_options::parse_incremental_update(const char*, const char*,
 342                                           Command_line*)
 343 {
 344   this->incremental_mode_ = INCREMENTAL_UPDATE;
 345 }
 346
 347 void
 348 General_options::parse_incremental_changed(const char*, const char*,
 349                                            Command_line*)
 350 {
 351   this->implicit_incremental_ = true;
 352   this->incremental_disposition_ = INCREMENTAL_CHANGED;
 353 }
 354
 355 void
 356 General_options::parse_incremental_unchanged(const char*, const char*,
 357                                              Command_line*)
 358 {
 359   this->implicit_incremental_ = true;
 360   this->incremental_disposition_ = INCREMENTAL_UNCHANGED;
 361 }
 362
 363 void
 364 General_options::parse_incremental_unknown(const char*, const char*,
 365                                            Command_line*)
 366 {
 367   this->implicit_incremental_ = true;
 368   this->incremental_disposition_ = INCREMENTAL_CHECK;
 369 }
 370
 371 void
 372 General_options::parse_library(const char*, const char* arg,
 373                                Command_line* cmdline)
 374 {
 375   Input_file_argument::Input_file_type type;
 376   const char* name;
 377   if (arg[0] == ':')
 378     {
 379       type = Input_file_argument::INPUT_FILE_TYPE_SEARCHED_FILE;
 380       name = arg + 1;
 381     }
 382   else
 383     {
 384       type = Input_file_argument::INPUT_FILE_TYPE_LIBRARY;
 385       name = arg;
 386     }
 387   Input_file_argument file(name, type, "", false, *this);
 388   cmdline->inputs().add_file(file);
 389 }
 390
 391 #ifdef ENABLE_PLUGINS
 392 void
 393 General_options::parse_plugin(const char*, const char* arg,
 394                               Command_line*)
 395 {
 396   this->add_plugin(arg);
 397 }
 398
 399 // Parse --plugin-opt.
 400
 401 void
 402 General_options::parse_plugin_opt(const char*, const char* arg,
 403                                   Command_line*)
 404 {
 405   this->add_plugin_option(arg);
 406 }
 407 #endif // ENABLE_PLUGINS
 408
 409 void
 410 General_options::parse_R(const char* option, const char* arg,
 411                          Command_line* cmdline)
 412 {
 413   struct stat s;
 414   if (::stat(arg, &s) != 0 || S_ISDIR(s.st_mode))
 415     this->add_to_rpath(arg);
 416   else
 417     this->parse_just_symbols(option, arg, cmdline);
 418 }
 419
 420 void
 421 General_options::parse_just_symbols(const char*, const char* arg,
 422                                     Command_line* cmdline)
 423 {
 424   Input_file_argument file(arg, Input_file_argument::INPUT_FILE_TYPE_FILE,
 425                            "", true, *this);
 426   cmdline->inputs().add_file(file);
 427 }
 428
 429 // Handle --section-start.
 430
 431 void
 432 General_options::parse_section_start(const char*, const char* arg,
 433                                      Command_line*)
 434 {
 435   const char* eq = strchr(arg, '=');
 436   if (eq == NULL)
 437     {
 438       gold_error(_("invalid argument to --section-start; "
 439                    "must be SECTION=ADDRESS"));
 440       return;
 441     }
 442
 443   std::string section_name(arg, eq - arg);
 444
 445   ++eq;
 446   const char* val_start = eq;
 447   if (eq[0] == '0' && (eq[1] == 'x' || eq[1] == 'X'))
 448     eq += 2;
 449   if (*eq == '\0')
 450     {
 451       gold_error(_("--section-start address missing"));
 452       return;
 453     }
 454   uint64_t addr = 0;
 455   hex_init();
 456   for (; *eq != '\0'; ++eq)
 457     {
 458       if (!hex_p(*eq))
 459         {
 460           gold_error(_("--section-start argument %s is not a valid hex number"),
 461                      val_start);
 462           return;
 463         }
 464       addr <<= 4;
 465       addr += hex_value(*eq);
 466     }
 467
 468   this->section_starts_[section_name] = addr;
 469 }
 470
 471 // Look up a --section-start value.
 472
 473 bool
 474 General_options::section_start(const char* secname, uint64_t* paddr) const
 475 {
 476   if (this->section_starts_.empty())
 477     return false;
 478   std::map<std::string, uint64_t>::const_iterator p =
 479     this->section_starts_.find(secname);
 480   if (p == this->section_starts_.end())
 481     return false;
 482   *paddr = p->second;
 483   return true;
 484 }
 485
 486 void
 487 General_options::parse_static(const char*, const char*, Command_line*)
 488 {
 489   this->set_static(true);
 490 }
 491
 492 void
 493 General_options::parse_script(const char*, const char* arg,
 494                               Command_line* cmdline)
 495 {
 496   if (!read_commandline_script(arg, cmdline))
 497     gold::gold_fatal(_("unable to parse script file %s"), arg);
 498 }
 499
 500 void
 501 General_options::parse_version_script(const char*, const char* arg,
 502                                       Command_line* cmdline)
 503 {
 504   if (!read_version_script(arg, cmdline))
 505     gold::gold_fatal(_("unable to parse version script file %s"), arg);
 506 }
 507
 508 void
 509 General_options::parse_dynamic_list(const char*, const char* arg,
 510                                     Command_line* cmdline)
 511 {
 512   if (!read_dynamic_list(arg, cmdline, &this->dynamic_list_))
 513     gold::gold_fatal(_("unable to parse dynamic-list script file %s"), arg);
 514 }
 515
 516 void
 517 General_options::parse_start_group(const char*, const char*,
 518                                    Command_line* cmdline)
 519 {
 520   cmdline->inputs().start_group();
 521 }
 522
 523 void
 524 General_options::parse_end_group(const char*, const char*,
 525                                  Command_line* cmdline)
 526 {
 527   cmdline->inputs().end_group();
 528 }
 529
 530 void
 531 General_options::parse_start_lib(const char*, const char*,
 532                                  Command_line* cmdline)
 533 {
 534   cmdline->inputs().start_lib(cmdline->position_dependent_options());
 535 }
 536
 537 void
 538 General_options::parse_end_lib(const char*, const char*,
 539                                Command_line* cmdline)
 540 {
 541   cmdline->inputs().end_lib();
 542 }
 543
 544 // The function add_excluded_libs() in ld/ldlang.c of GNU ld breaks up a list
 545 // of names separated by commas or colons and puts them in a linked list.
 546 // We implement the same parsing of names here but store names in an unordered
 547 // map to speed up searching of names.
 548
 549 void
 550 General_options::parse_exclude_libs(const char*, const char* arg,
 551                                     Command_line*)
 552 {
 553   const char* p = arg;
 554
 555   while (*p != '\0')
 556     {
 557       size_t length = strcspn(p, ",:");
 558       this->excluded_libs_.insert(std::string(p, length));
 559       p += (p[length] ? length + 1 : length);
 560     }
 561 }
 562
 563 // The checking logic is based on the function check_excluded_libs() in
 564 // ld/ldlang.c of GNU ld but our implementation is different because we use
 565 // an unordered map instead of a linked list, which is what GNU ld uses.  GNU
 566 // ld searches sequentially in the excluded libs list.  For a given archive,
 567 // a match is found if the archive's name matches exactly one of the list
 568 // entry or if the archive's name is of the form FOO.a and FOO matches exactly
 569 // one of the list entry.  An entry "ALL" in the list is considered as a
 570 // wild-card and matches any given name.
 571
 572 bool
 573 General_options::check_excluded_libs(const std::string &name) const
 574 {
 575   Unordered_set<std::string>::const_iterator p;
 576
 577   // Exit early for the most common case.
 578   if (excluded_libs_.empty())
 579     return false;
 580
 581   // If we see "ALL", all archives are excluded from automatic export.
 582   p = excluded_libs_.find(std::string("ALL"));
 583   if (p != excluded_libs_.end())
 584     return true;
 585
 586   // First strip off any directories in name.
 587   const char* basename = lbasename(name.c_str());
 588
 589   // Try finding an exact match.
 590   p = excluded_libs_.find(std::string(basename));
 591   if (p != excluded_libs_.end())
 592     return true;
 593
 594   // Try matching NAME without ".a" at the end.
 595   size_t length = strlen(basename);
 596   if ((length >= 2)
 597       && (basename[length - 2] == '.')
 598       && (basename[length - 1] == 'a'))
 599     {
 600       p = excluded_libs_.find(std::string(basename, length - 2));
 601       if (p != excluded_libs_.end())
 602         return true;
 603     }
 604
 605   return false;
 606 }
 607
 608 // Recognize input and output target names.  The GNU linker accepts
 609 // these with --format and --oformat.  This code is intended to be
 610 // minimally compatible.  In practice for an ELF target this would be
 611 // the same target as the input files; that name always start with
 612 // "elf".  Non-ELF targets would be "srec", "symbolsrec", "tekhex",
 613 // "binary", "ihex".
 614
 615 General_options::Object_format
 616 General_options::string_to_object_format(const char* arg)
 617 {
 618   if (strncmp(arg, "elf", 3) == 0)
 619     return gold::General_options::OBJECT_FORMAT_ELF;
 620   else if (strcmp(arg, "binary") == 0)
 621     return gold::General_options::OBJECT_FORMAT_BINARY;
 622   else
 623     {
 624       gold::gold_error(_("format '%s' not supported; treating as elf "
 625                          "(supported formats: elf, binary)"),
 626                        arg);
 627       return gold::General_options::OBJECT_FORMAT_ELF;
 628     }
 629 }
 630
 631 void
 632 General_options::parse_fix_v4bx(const char*, const char*,
 633                                 Command_line*)
 634 {
 635   this->fix_v4bx_ = FIX_V4BX_REPLACE;
 636 }
 637
 638 void
 639 General_options::parse_fix_v4bx_interworking(const char*, const char*,
 640                                              Command_line*)
 641 {
 642   this->fix_v4bx_ = FIX_V4BX_INTERWORKING;
 643 }
 644
 645 void
 646 General_options::parse_EB(const char*, const char*, Command_line*)
 647 {
 648   this->endianness_ = ENDIANNESS_BIG;
 649 }
 650
 651 void
 652 General_options::parse_EL(const char*, const char*, Command_line*)
 653 {
 654   this->endianness_ = ENDIANNESS_LITTLE;
 655 }
 656
 657 } // End namespace gold.
 658
 659 namespace
 660 {
 661
 662 void
 663 usage()
 664 {
 665   fprintf(stderr,
 666           _("%s: use the --help option for usage information\n"),
 667           gold::program_name);
 668   ::exit(EXIT_FAILURE);
 669 }
 670
 671 void
 672 usage(const char* msg, const char* opt)
 673 {
 674   fprintf(stderr,
 675           _("%s: %s: %s\n"),
 676           gold::program_name, opt, msg);
 677   usage();
 678 }
 679
 680 // If the default sysroot is relocatable, try relocating it based on
 681 // the prefix FROM.
 682
 683 static char*
 684 get_relative_sysroot(const char* from)
 685 {
 686   char* path = make_relative_prefix(gold::program_name, from,
 687                                     TARGET_SYSTEM_ROOT);
 688   if (path != NULL)
 689     {
 690       struct stat s;
 691       if (::stat(path, &s) == 0 && S_ISDIR(s.st_mode))
 692         return path;
 693       free(path);
 694     }
 695
 696   return NULL;
 697 }
 698
 699 // Return the default sysroot.  This is set by the --with-sysroot
 700 // option to configure.  Note we do not free the return value of
 701 // get_relative_sysroot, which is a small memory leak, but is
 702 // necessary since we store this pointer directly in General_options.
 703
 704 static const char*
 705 get_default_sysroot()
 706 {
 707   const char* sysroot = TARGET_SYSTEM_ROOT;
 708   if (*sysroot == '\0')
 709     return NULL;
 710
 711   if (TARGET_SYSTEM_ROOT_RELOCATABLE)
 712     {
 713       char* path = get_relative_sysroot(BINDIR);
 714       if (path == NULL)
 715         path = get_relative_sysroot(TOOLBINDIR);
 716       if (path != NULL)
 717         return path;
 718     }
 719
 720   return sysroot;
 721 }
 722
 723 // Parse a long option.  Such options have the form
 724 // <-|--><option>[=arg].  If "=arg" is not present but the option
 725 // takes an argument, the next word is taken to the be the argument.
 726 // If equals_only is set, then only the <option>=<arg> form is
 727 // accepted, not the <option><space><arg> form.  Returns a One_option
 728 // struct or NULL if argv[i] cannot be parsed as a long option.  In
 729 // the not-NULL case, *arg is set to the option's argument (NULL if
 730 // the option takes no argument), and *i is advanced past this option.
 731 // NOTE: it is safe for argv and arg to point to the same place.
 732 gold::options::One_option*
 733 parse_long_option(int argc, const char** argv, bool equals_only,
 734                   const char** arg, int* i)
 735 {
 736   const char* const this_argv = argv[*i];
 737
 738   const char* equals = strchr(this_argv, '=');
 739   const char* option_start = this_argv + strspn(this_argv, "-");
 740   std::string option(option_start,
 741                      equals ? equals - option_start : strlen(option_start));
 742
 743   gold::options::Option_map::iterator it
 744       = gold::options::long_options->find(option);
 745   if (it == gold::options::long_options->end())
 746     return NULL;
 747
 748   gold::options::One_option* retval = it->second;
 749
 750   // If the dash-count doesn't match, we fail.
 751   if (this_argv[0] != '-')  // no dashes at all: had better be "-z <longopt>"
 752     {
 753       if (retval->dashes != gold::options::DASH_Z)
 754         return NULL;
 755     }
 756   else if (this_argv[1] != '-')   // one dash
 757     {
 758       if (retval->dashes != gold::options::ONE_DASH
 759           && retval->dashes != gold::options::EXACTLY_ONE_DASH
 760           && retval->dashes != gold::options::TWO_DASHES)
 761         return NULL;
 762     }
 763   else                            // two dashes (or more!)
 764     {
 765       if (retval->dashes != gold::options::TWO_DASHES
 766           && retval->dashes != gold::options::EXACTLY_TWO_DASHES
 767           && retval->dashes != gold::options::ONE_DASH)
 768         return NULL;
 769     }
 770
 771   // Now that we know the option is good (or else bad in a way that
 772   // will cause us to die), increment i to point past this argv.
 773   ++(*i);
 774
 775   // Figure out the option's argument, if any.
 776   if (!retval->takes_argument())
 777     {
 778       if (equals)
 779         usage(_("unexpected argument"), this_argv);
 780       else
 781         *arg = NULL;
 782     }
 783   else
 784     {
 785       if (equals)
 786         *arg = equals + 1;
 787       else if (retval->takes_optional_argument())
 788         *arg = retval->default_value;
 789       else if (*i < argc && !equals_only)
 790         *arg = argv[(*i)++];
 791       else
 792         usage(_("missing argument"), this_argv);
 793     }
 794
 795   return retval;
 796 }
 797
 798 // Parse a short option.  Such options have the form -<option>[arg].
 799 // If "arg" is not present but the option takes an argument, the next
 800 // word is taken to the be the argument.  If the option does not take
 801 // an argument, it may be followed by another short option.  Returns a
 802 // One_option struct or NULL if argv[i] cannot be parsed as a short
 803 // option.  In the not-NULL case, *arg is set to the option's argument
 804 // (NULL if the option takes no argument), and *i is advanced past
 805 // this option.  This function keeps *i the same if we parsed a short
 806 // option that does not take an argument, that looks to be followed by
 807 // another short option in the same word.
 808 gold::options::One_option*
 809 parse_short_option(int argc, const char** argv, int pos_in_argv_i,
 810                    const char** arg, int* i)
 811 {
 812   const char* const this_argv = argv[*i];
 813
 814   if (this_argv[0] != '-')
 815     return NULL;
 816
 817   // We handle -z as a special case.
 818   static gold::options::One_option dash_z("", gold::options::DASH_Z,
 819                                           'z', "", NULL, "Z-OPTION", false,
 820                                           NULL);
 821   gold::options::One_option* retval = NULL;
 822   if (this_argv[pos_in_argv_i] == 'z')
 823     retval = &dash_z;
 824   else
 825     {
 826       const int char_as_int = static_cast<int>(this_argv[pos_in_argv_i]);
 827       if (char_as_int > 0 && char_as_int < 128)
 828         retval = gold::options::short_options[char_as_int];
 829     }
 830
 831   if (retval == NULL)
 832     return NULL;
 833
 834   // Figure out the option's argument, if any.
 835   if (!retval->takes_argument())
 836     {
 837       *arg = NULL;
 838       // We only advance past this argument if it's the only one in argv.
 839       if (this_argv[pos_in_argv_i + 1] == '\0')
 840         ++(*i);
 841     }
 842   else
 843     {
 844       // If we take an argument, we'll eat up this entire argv entry.
 845       ++(*i);
 846       if (this_argv[pos_in_argv_i + 1] != '\0')
 847         *arg = this_argv + pos_in_argv_i + 1;
 848       else if (retval->takes_optional_argument())
 849         *arg = retval->default_value;
 850       else if (*i < argc)
 851         *arg = argv[(*i)++];
 852       else
 853         usage(_("missing argument"), this_argv);
 854     }
 855
 856   // If we're a -z option, we need to parse our argument as a
 857   // long-option, e.g. "-z stacksize=8192".
 858   if (retval == &dash_z)
 859     {
 860       int dummy_i = 0;
 861       const char* dash_z_arg = *arg;
 862       retval = parse_long_option(1, arg, true, arg, &dummy_i);
 863       if (retval == NULL)
 864         usage(_("unknown -z option"), dash_z_arg);
 865     }
 866
 867   return retval;
 868 }
 869
 870 } // End anonymous namespace.
 871
 872 namespace gold
 873 {
 874
 875 General_options::General_options()
 876   : printed_version_(false),
 877     execstack_status_(EXECSTACK_FROM_INPUT),
 878     icf_status_(ICF_NONE),
 879     static_(false),
 880     do_demangle_(false),
 881     plugins_(NULL),
 882     dynamic_list_(),
 883     incremental_mode_(INCREMENTAL_OFF),
 884     incremental_disposition_(INCREMENTAL_CHECK),
 885     implicit_incremental_(false),
 886     excluded_libs_(),
 887     symbols_to_retain_(),
 888     section_starts_(),
 889     fix_v4bx_(FIX_V4BX_NONE),
 890     endianness_(ENDIANNESS_NOT_SET)
 891 {
 892   // Turn off option registration once construction is complete.
 893   gold::options::ready_to_register = false;
 894 }
 895
 896 General_options::Object_format
 897 General_options::format_enum() const
 898 {
 899   return General_options::string_to_object_format(this->format());
 900 }
 901
 902 General_options::Object_format
 903 General_options::oformat_enum() const
 904 {
 905   return General_options::string_to_object_format(this->oformat());
 906 }
 907
 908 // Add the sysroot, if any, to the search paths.
 909
 910 void
 911 General_options::add_sysroot()
 912 {
 913   if (this->sysroot() == NULL || this->sysroot()[0] == '\0')
 914     {
 915       this->set_sysroot(get_default_sysroot());
 916       if (this->sysroot() == NULL || this->sysroot()[0] == '\0')
 917         return;
 918     }
 919
 920   char* canonical_sysroot = lrealpath(this->sysroot());
 921
 922   for (Dir_list::iterator p = this->library_path_.value.begin();
 923        p != this->library_path_.value.end();
 924        ++p)
 925     p->add_sysroot(this->sysroot(), canonical_sysroot);
 926
 927   free(canonical_sysroot);
 928 }
 929
 930 // Return whether FILENAME is in a system directory.
 931
 932 bool
 933 General_options::is_in_system_directory(const std::string& filename) const
 934 {
 935   for (Dir_list::const_iterator p = this->library_path_.value.begin();
 936        p != this->library_path_.value.end();
 937        ++p)
 938     {
 939       // We use a straight string comparison rather than calling
 940       // FILENAME_CMP because we are only interested in the cases
 941       // where we found the file in a system directory, which means
 942       // that we used the directory name as a prefix for a -L search.
 943       if (p->is_system_directory()
 944           && filename.compare(0, p->name().size(), p->name()) == 0)
 945         return true;
 946     }
 947   return false;
 948 }
 949
 950 // Add a plugin to the list of plugins.
 951
 952 void
 953 General_options::add_plugin(const char* filename)
 954 {
 955   if (this->plugins_ == NULL)
 956     this->plugins_ = new Plugin_manager(*this);
 957   this->plugins_->add_plugin(filename);
 958 }
 959
 960 // Add a plugin option to a plugin.
 961
 962 void
 963 General_options::add_plugin_option(const char* arg)
 964 {
 965   if (this->plugins_ == NULL)
 966     gold_fatal("--plugin-opt requires --plugin.");
 967   this->plugins_->add_plugin_option(arg);
 968 }
 969
 970 // Set up variables and other state that isn't set up automatically by
 971 // the parse routine, and ensure options don't contradict each other
 972 // and are otherwise kosher.
 973
 974 void
 975 General_options::finalize()
 976 {
 977   // Normalize the strip modifiers.  They have a total order:
 978   // strip_all > strip_debug > strip_non_line > strip_debug_gdb.
 979   // If one is true, set all beneath it to true as well.
 980   if (this->strip_all())
 981     this->set_strip_debug(true);
 982   if (this->strip_debug())
 983     this->set_strip_debug_non_line(true);
 984   if (this->strip_debug_non_line())
 985     this->set_strip_debug_gdb(true);
 986
 987   if (this->Bshareable())
 988     this->set_shared(true);
 989
 990   // If the user specifies both -s and -r, convert the -s to -S.
 991   // -r requires us to keep externally visible symbols!
 992   if (this->strip_all() && this->relocatable())
 993     {
 994       this->set_strip_all(false);
 995       gold_assert(this->strip_debug());
 996     }
 997
 998   // For us, -dc and -dp are synonyms for --define-common.
 999   if (this->dc())
1000     this->set_define_common(true);
1001   if (this->dp())
1002     this->set_define_common(true);
1003
1004   // We also set --define-common if we're not relocatable, as long as
1005   // the user didn't explicitly ask for something different.
1006   if (!this->user_set_define_common())
1007     this->set_define_common(!this->relocatable());
1008
1009   // execstack_status_ is a three-state variable; update it based on
1010   // -z [no]execstack.
1011   if (this->execstack())
1012     this->set_execstack_status(EXECSTACK_YES);
1013   else if (this->noexecstack())
1014     this->set_execstack_status(EXECSTACK_NO);
1015
1016   // icf_status_ is a three-state variable; update it based on the
1017   // value of this->icf().
1018   if (strcmp(this->icf(), "none") == 0)
1019     this->set_icf_status(ICF_NONE);
1020   else if (strcmp(this->icf(), "safe") == 0)
1021     this->set_icf_status(ICF_SAFE);
1022   else
1023     this->set_icf_status(ICF_ALL);
1024
1025   // Handle the optional argument for --demangle.
1026   if (this->user_set_demangle())
1027     {
1028       this->set_do_demangle(true);
1029       const char* style = this->demangle();
1030       if (*style != '\0')
1031         {
1032           enum demangling_styles style_code;
1033
1034           style_code = cplus_demangle_name_to_style(style);
1035           if (style_code == unknown_demangling)
1036             gold_fatal("unknown demangling style '%s'", style);
1037           cplus_demangle_set_style(style_code);
1038         }
1039     }
1040   else if (this->user_set_no_demangle())
1041     this->set_do_demangle(false);
1042   else
1043     {
1044       // Testing COLLECT_NO_DEMANGLE makes our default demangling
1045       // behaviour identical to that of gcc's linker wrapper.
1046       this->set_do_demangle(getenv("COLLECT_NO_DEMANGLE") == NULL);
1047     }
1048
1049   // -M is equivalent to "-Map -".
1050   if (this->print_map() && !this->user_set_Map())
1051     {
1052       this->set_Map("-");
1053       this->set_user_set_Map();
1054     }
1055
1056   // Using -n or -N implies -static.
1057   if (this->nmagic() || this->omagic())
1058     this->set_static(true);
1059
1060   // If --thread_count is specified, it applies to
1061   // --thread-count-{initial,middle,final}, though it doesn't override
1062   // them.
1063   if (this->thread_count() > 0 && this->thread_count_initial() == 0)
1064     this->set_thread_count_initial(this->thread_count());
1065   if (this->thread_count() > 0 && this->thread_count_middle() == 0)
1066     this->set_thread_count_middle(this->thread_count());
1067   if (this->thread_count() > 0 && this->thread_count_final() == 0)
1068     this->set_thread_count_final(this->thread_count());
1069
1070   // Let's warn if you set the thread-count but we're going to ignore it.
1071 #ifndef ENABLE_THREADS
1072   if (this->threads())
1073     {
1074       gold_warning(_("ignoring --threads: "
1075                      "%s was compiled without thread support"),
1076                    program_name);
1077       this->set_threads(false);
1078     }
1079   if (this->thread_count() > 0 || this->thread_count_initial() > 0
1080       || this->thread_count_middle() > 0 || this->thread_count_final() > 0)
1081     gold_warning(_("ignoring --thread-count: "
1082                    "%s was compiled without thread support"),
1083                  program_name);
1084 #endif
1085
1086   if (this->user_set_Y())
1087     {
1088       std::string s = this->Y();
1089       if (s.compare(0, 2, "P,") == 0)
1090         s.erase(0, 2);
1091
1092       size_t pos = 0;
1093       size_t next_pos;
1094       do
1095         {
1096           next_pos = s.find(':', pos);
1097           size_t len = (next_pos == std::string::npos
1098                         ? next_pos
1099                         : next_pos - pos);
1100           if (len != 0)
1101             this->add_to_library_path_with_sysroot(s.substr(pos, len).c_str());
1102           pos = next_pos + 1;
1103         }
1104       while (next_pos != std::string::npos);
1105     }
1106   else if (!this->nostdlib())
1107     {
1108       // Even if they don't specify it, we add -L /lib and -L /usr/lib.
1109       // FIXME: We should only do this when configured in native mode.
1110       this->add_to_library_path_with_sysroot("/lib");
1111       this->add_to_library_path_with_sysroot("/usr/lib");
1112     }
1113
1114   // Parse the contents of -retain-symbols-file into a set.
1115   if (this->retain_symbols_file())
1116     {
1117       std::ifstream in;
1118       in.open(this->retain_symbols_file());
1119       if (!in)
1120         gold_fatal(_("unable to open -retain-symbols-file file %s: %s"),
1121                    this->retain_symbols_file(), strerror(errno));
1122       std::string line;
1123       std::getline(in, line);   // this chops off the trailing \n, if any
1124       while (in)
1125         {
1126           if (!line.empty() && line[line.length() - 1] == '\r')   // Windows
1127             line.resize(line.length() - 1);
1128           this->symbols_to_retain_.insert(line);
1129           std::getline(in, line);
1130         }
1131     }
1132
1133   if (this->shared() && !this->user_set_allow_shlib_undefined())
1134     this->set_allow_shlib_undefined(true);
1135
1136   // Normalize library_path() by adding the sysroot to all directories
1137   // in the path, as appropriate.
1138   this->add_sysroot();
1139
1140   // Now that we've normalized the options, check for contradictory ones.
1141   if (this->shared() && this->is_static())
1142     gold_fatal(_("-shared and -static are incompatible"));
1143   if (this->shared() && this->pie())
1144     gold_fatal(_("-shared and -pie are incompatible"));
1145
1146   if (this->shared() && this->relocatable())
1147     gold_fatal(_("-shared and -r are incompatible"));
1148   if (this->pie() && this->relocatable())
1149     gold_fatal(_("-pie and -r are incompatible"));
1150
1151   // TODO: implement support for -retain-symbols-file with -r, if needed.
1152   if (this->relocatable() && this->retain_symbols_file())
1153     gold_fatal(_("-retain-symbols-file does not yet work with -r"));
1154
1155   if (this->oformat_enum() != General_options::OBJECT_FORMAT_ELF
1156       && (this->shared()
1157           || this->pie()
1158           || this->relocatable()))
1159     gold_fatal(_("binary output format not compatible "
1160                  "with -shared or -pie or -r"));
1161
1162   if (this->user_set_hash_bucket_empty_fraction()
1163       && (this->hash_bucket_empty_fraction() < 0.0
1164           || this->hash_bucket_empty_fraction() >= 1.0))
1165     gold_fatal(_("--hash-bucket-empty-fraction value %g out of range "
1166                  "[0.0, 1.0)"),
1167                this->hash_bucket_empty_fraction());
1168
1169   if (this->implicit_incremental_ && this->incremental_mode_ == INCREMENTAL_OFF)
1170     gold_fatal(_("Options --incremental-changed, --incremental-unchanged, "
1171                  "--incremental-unknown require the use of --incremental"));
1172
1173   // FIXME: we can/should be doing a lot more sanity checking here.
1174 }
1175
1176 // Search_directory methods.
1177
1178 // This is called if we have a sysroot.  Apply the sysroot if
1179 // appropriate.  Record whether the directory is in the sysroot.
1180
1181 void
1182 Search_directory::add_sysroot(const char* sysroot,
1183                               const char* canonical_sysroot)
1184 {
1185   gold_assert(*sysroot != '\0');
1186   if (this->put_in_sysroot_)
1187     {
1188       if (!IS_DIR_SEPARATOR(this->name_[0])
1189           && !IS_DIR_SEPARATOR(sysroot[strlen(sysroot) - 1]))
1190         this->name_ = '/' + this->name_;
1191       this->name_ = sysroot + this->name_;
1192       this->is_in_sysroot_ = true;
1193     }
1194   else
1195     {
1196       // Check whether this entry is in the sysroot.  To do this
1197       // correctly, we need to use canonical names.  Otherwise we will
1198       // get confused by the ../../.. paths that gcc tends to use.
1199       char* canonical_name = lrealpath(this->name_.c_str());
1200       int canonical_name_len = strlen(canonical_name);
1201       int canonical_sysroot_len = strlen(canonical_sysroot);
1202       if (canonical_name_len > canonical_sysroot_len
1203           && IS_DIR_SEPARATOR(canonical_name[canonical_sysroot_len]))
1204         {
1205           canonical_name[canonical_sysroot_len] = '\0';
1206           if (FILENAME_CMP(canonical_name, canonical_sysroot) == 0)
1207             this->is_in_sysroot_ = true;
1208         }
1209       free(canonical_name);
1210     }
1211 }
1212
1213 // Input_arguments methods.
1214
1215 // Add a file to the list.
1216
1217 Input_argument&
1218 Input_arguments::add_file(Input_file_argument& file)
1219 {
1220   file.set_arg_serial(++this->file_count_);
1221   if (this->in_group_)
1222     {
1223       gold_assert(!this->input_argument_list_.empty());
1224       gold_assert(this->input_argument_list_.back().is_group());
1225       return this->input_argument_list_.back().group()->add_file(file);
1226     }
1227   if (this->in_lib_)
1228     {
1229       gold_assert(!this->input_argument_list_.empty());
1230       gold_assert(this->input_argument_list_.back().is_lib());
1231       return this->input_argument_list_.back().lib()->add_file(file);
1232     }
1233   this->input_argument_list_.push_back(Input_argument(file));
1234   return this->input_argument_list_.back();
1235 }
1236
1237 // Start a group.
1238
1239 void
1240 Input_arguments::start_group()
1241 {
1242   if (this->in_group_)
1243     gold_fatal(_("May not nest groups"));
1244   if (this->in_lib_)
1245     gold_fatal(_("may not nest groups in libraries"));
1246   Input_file_group* group = new Input_file_group();
1247   this->input_argument_list_.push_back(Input_argument(group));
1248   this->in_group_ = true;
1249 }
1250
1251 // End a group.
1252
1253 void
1254 Input_arguments::end_group()
1255 {
1256   if (!this->in_group_)
1257     gold_fatal(_("Group end without group start"));
1258   this->in_group_ = false;
1259 }
1260
1261 // Start a lib.
1262
1263 void
1264 Input_arguments::start_lib(const Position_dependent_options& options)
1265 {
1266   if (this->in_lib_)
1267     gold_fatal(_("may not nest libraries"));
1268   if (this->in_group_)
1269     gold_fatal(_("may not nest libraries in groups"));
1270   Input_file_lib* lib = new Input_file_lib(options);
1271   this->input_argument_list_.push_back(Input_argument(lib));
1272   this->in_lib_ = true;
1273 }
1274
1275 // End a lib.
1276
1277 void
1278 Input_arguments::end_lib()
1279 {
1280   if (!this->in_lib_)
1281     gold_fatal(_("lib end without lib start"));
1282   this->in_lib_ = false;
1283 }
1284
1285 // Command_line options.
1286
1287 Command_line::Command_line()
1288 {
1289 }
1290
1291 // Pre_options is the hook that sets the ready_to_register flag.
1292
1293 Command_line::Pre_options::Pre_options()
1294 {
1295   gold::options::ready_to_register = true;
1296 }
1297
1298 // Process the command line options.  For process_one_option, i is the
1299 // index of argv to process next, and must be an option (that is,
1300 // start with a dash).  The return value is the index of the next
1301 // option to process (i+1 or i+2, or argc to indicate processing is
1302 // done).  no_more_options is set to true if (and when) "--" is seen
1303 // as an option.
1304
1305 int
1306 Command_line::process_one_option(int argc, const char** argv, int i,
1307                                  bool* no_more_options)
1308 {
1309   gold_assert(argv[i][0] == '-' && !(*no_more_options));
1310
1311   // If we are reading "--", then just set no_more_options and return.
1312   if (argv[i][1] == '-' && argv[i][2] == '\0')
1313     {
1314       *no_more_options = true;
1315       return i + 1;
1316     }
1317
1318   int new_i = i;
1319   options::One_option* option = NULL;
1320   const char* arg = NULL;
1321
1322   // First, try to process argv as a long option.
1323   option = parse_long_option(argc, argv, false, &arg, &new_i);
1324   if (option)
1325     {
1326       option->reader->parse_to_value(argv[i], arg, this, &this->options_);
1327       return new_i;
1328     }
1329
1330   // Now, try to process argv as a short option.  Since several short
1331   // options can be combined in one argv, we may have to parse a lot
1332   // until we're done reading this argv.
1333   int pos_in_argv_i = 1;
1334   while (new_i == i)
1335     {
1336       option = parse_short_option(argc, argv, pos_in_argv_i, &arg, &new_i);
1337       if (!option)
1338         break;
1339       option->reader->parse_to_value(argv[i], arg, this, &this->options_);
1340       ++pos_in_argv_i;
1341     }
1342   if (option)
1343     return new_i;
1344
1345   // I guess it's neither a long option nor a short option.
1346   usage(_("unknown option"), argv[i]);
1347   return argc;
1348 }
1349
1350
1351 void
1352 Command_line::process(int argc, const char** argv)
1353 {
1354   bool no_more_options = false;
1355   int i = 0;
1356   while (i < argc)
1357     {
1358       this->position_options_.copy_from_options(this->options());
1359       if (no_more_options || argv[i][0] != '-')
1360         {
1361           Input_file_argument file(argv[i],
1362                                    Input_file_argument::INPUT_FILE_TYPE_FILE,
1363                                    "", false, this->position_options_);
1364           this->inputs_.add_file(file);
1365           ++i;
1366         }
1367       else
1368         i = process_one_option(argc, argv, i, &no_more_options);
1369     }
1370
1371   if (this->inputs_.in_group())
1372     {
1373       fprintf(stderr, _("%s: missing group end\n"), program_name);
1374       usage();
1375     }
1376
1377   // Normalize the options and ensure they don't contradict each other.
1378   this->options_.finalize();
1379 }
1380
1381 // Finalize the version script options and return them.
1382
1383 const Version_script_info&
1384 Command_line::version_script()
1385 {
1386   this->options_.finalize_dynamic_list();
1387   Version_script_info* vsi = this->script_options_.version_script_info();
1388   vsi->finalize();
1389   return *vsi;
1390 }
1391
1392 } // End namespace gold.