gold/options.cc

   1 // options.c -- handle command line options for gold
   2
   3 #include <iostream>
   4
   5 #include "gold.h"
   6 #include "options.h"
   7
   8 namespace gold
   9 {
  10
  11 // The information we keep for a single command line option.
  12
  13 struct options::One_option
  14 {
  15   // The single character option name, or '\0' if this is only a long
  16   // option.
  17   char short_option;
  18
  19   // The long option name, or NULL if this is only a short option.
  20   const char* long_option;
  21
  22   // Description of the option for --help output, or NULL if there is none.
  23   const char* doc;
  24
  25   // How to print the option name in --help output, or NULL to use the
  26   // default.
  27   const char* help_output;
  28
  29   // Long option dash control.  This is ignored if long_option is
  30   // NULL.
  31   enum
  32     {
  33       // Long option normally takes one dash; two dashes are also
  34       // accepted.
  35       ONE_DASH,
  36       // Long option normally takes two dashes; one dash is also
  37       // accepted.
  38       TWO_DASHES,
  39       // Long option always takes two dashes.
  40       EXACTLY_TWO_DASHES
  41     } dash;
  42
  43   // Function for special handling, or NULL.  Returns the number of
  44   // arguments to skip.  This will normally be at least 1, but it may
  45   // be 0 if this function changes *argv.  ARG points to the location
  46   // in *ARGV where the option starts, which may be helpful for a
  47   // short option.
  48   int (*special)(int argc, char** argv, char *arg, Command_line*);
  49
  50   // If this is a position independent option which does not take an
  51   // argument, this is the member function to call to record it.
  52   void (General_options::*general_noarg)();
  53
  54   // If this is a position independent function which takes an
  55   // argument, this is the member function to call to record it.
  56   void (General_options::*general_arg)(const char*);
  57
  58   // If this is a position dependent option which does not take an
  59   // argument, this is the member function to call to record it.
  60   void (Position_dependent_options::*dependent_noarg)();
  61
  62   // If this is a position dependent option which takes an argument,
  63   // this is the member function to record it.
  64   void (Position_dependent_options::*dependent_arg)(const char*);
  65
  66   // Return whether this option takes an argument.
  67   bool
  68   takes_argument() const
  69   { return this->general_arg != NULL || this->dependent_arg != NULL; }
  70 };
  71
  72 class options::Command_line_options
  73 {
  74  public:
  75   static const One_option options[];
  76   static const int options_size;
  77 };
  78
  79 } // End namespace gold.
  80
  81 namespace
  82 {
  83
  84 // Handle the special -l option, which adds an input file.
  85
  86 int
  87 library(int argc, char** argv, char* arg, gold::Command_line* cmdline)
  88 {
  89   return cmdline->process_l_option(argc, argv, arg);
  90 }
  91
  92 // Handle the special --start-group option.
  93
  94 int
  95 start_group(int, char**, char* arg, gold::Command_line* cmdline)
  96 {
  97   cmdline->start_group(arg);
  98   return 1;
  99 }
 100
 101 // Handle the special --end-group option.
 102
 103 int
 104 end_group(int, char**, char* arg, gold::Command_line* cmdline)
 105 {
 106   cmdline->end_group(arg);
 107   return 1;
 108 }
 109
 110 // Report usage information for ld --help, and exit.
 111
 112 int
 113 help(int, char**, char*, gold::Command_line*)
 114 {
 115   printf(_("Usage: %s [options] file...\nOptions:\n"), gold::program_name);
 116
 117   const int options_size = gold::options::Command_line_options::options_size;
 118   const gold::options::One_option* options =
 119     gold::options::Command_line_options::options;
 120   for (int i = 0; i < options_size; ++i)
 121     {
 122       if (options[i].doc == NULL)
 123         continue;
 124
 125       printf("  ");
 126       int len = 2;
 127       bool comma = false;
 128
 129       int j = i;
 130       do
 131         {
 132           if (options[j].help_output != NULL)
 133             {
 134               if (comma)
 135                 {
 136                   printf(", ");
 137                   len += 2;
 138                 }
 139               printf(options[j].help_output);
 140               len += std::strlen(options[i].help_output);
 141               comma = true;
 142             }
 143           else
 144             {
 145               if (options[j].short_option != '\0')
 146                 {
 147                   if (comma)
 148                     {
 149                       printf(", ");
 150                       len += 2;
 151                     }
 152                   printf("-%c", options[j].short_option);
 153                   len += 2;
 154                   comma = true;
 155                 }
 156
 157               if (options[j].long_option != NULL)
 158                 {
 159                   if (comma)
 160                     {
 161                       printf(", ");
 162                       len += 2;
 163                     }
 164                   if (options[j].dash == gold::options::One_option::ONE_DASH)
 165                     {
 166                       printf("-");
 167                       ++len;
 168                     }
 169                   else
 170                     {
 171                       printf("--");
 172                       len += 2;
 173                     }
 174                   printf("%s", options[j].long_option);
 175                   len += std::strlen(options[j].long_option);
 176                   comma = true;
 177                 }
 178             }
 179           ++j;
 180         }
 181       while (j < options_size && options[j].doc == NULL);
 182
 183       if (len >= 30)
 184         {
 185           printf("\n");
 186           len = 0;
 187         }
 188       for (; len < 30; ++len)
 189         std::putchar(' ');
 190
 191       std::puts(options[i].doc);
 192     }
 193
 194   gold::gold_exit(true);
 195
 196   return 0;
 197 }
 198
 199 } // End anonymous namespace.
 200
 201 namespace gold
 202 {
 203
 204 // Helper macros used to specify the options.  We could also do this
 205 // using constructors, but then g++ would generate code to initialize
 206 // the array.  We want the array to be initialized statically so that
 207 // we get better startup time.
 208
 209 #define GENERAL_NOARG(short_option, long_option, doc, help, dash, func) \
 210   { short_option, long_option, doc, help, options::One_option::dash, \
 211       NULL, func, NULL, NULL, NULL }
 212 #define GENERAL_ARG(short_option, long_option, doc, help, dash, func)   \
 213   { short_option, long_option, doc, help, options::One_option::dash, \
 214       NULL, NULL, func, NULL, NULL }
 215 #define POSDEP_NOARG(short_option, long_option, doc, help, dash, func)  \
 216   { short_option, long_option, doc, help, options::One_option::dash, \
 217       NULL,  NULL, NULL, func, NULL }
 218 #define POSDEP_ARG(short_option, long_option, doc, help, dash, func)    \
 219   { short_option, long_option, doc, help, options::One_option::dash, \
 220       NULL, NULL, NULL, NULL, func }
 221 #define SPECIAL(short_option, long_option, doc, help, dash, func)       \
 222   { short_option, long_option, doc, help, options::One_option::dash, \
 223       func, NULL, NULL, NULL, NULL }
 224
 225 // Here is the actual list of options which we accept.
 226
 227 const options::One_option
 228 options::Command_line_options::options[] =
 229 {
 230   SPECIAL('l', "library", N_("Search for library LIBNAME"),
 231           N_("-lLIBNAME, --library LIBNAME"), TWO_DASHES,
 232           &library),
 233   SPECIAL('(', "start-group", N_("Start a library search group"), NULL,
 234           TWO_DASHES, &start_group),
 235   SPECIAL(')', "end-group", N_("End a library search group"), NULL,
 236           TWO_DASHES, &end_group),
 237   GENERAL_NOARG('E', "export-dynamic", N_("Export all dynamic symbols"),
 238                 NULL, TWO_DASHES, &General_options::set_export_dynamic),
 239   GENERAL_ARG('I', "dynamic-linker", N_("Set dynamic linker path"),
 240               N_("-I PROGRAM, --dynamic-linker PROGRAM"), TWO_DASHES,
 241               &General_options::set_dynamic_linker),
 242   GENERAL_ARG('L', "library-path", N_("Add directory to search path"),
 243               N_("-L DIR, --library-path DIR"), TWO_DASHES,
 244               &General_options::add_to_search_path),
 245   GENERAL_ARG('m', NULL, N_("Ignored for compatibility"), NULL, ONE_DASH,
 246               &General_options::ignore),
 247   GENERAL_ARG('o', "output", N_("Set output file name"),
 248               N_("-o FILE, --output FILE"), TWO_DASHES,
 249               &General_options::set_output_file_name),
 250   GENERAL_NOARG('r', NULL, N_("Generate relocatable output"), NULL,
 251                 ONE_DASH, &General_options::set_relocatable),
 252   GENERAL_ARG('R', "rpath", N_("Add directory to runtime search path"),
 253               N_("-R DIR, -rpath DIR"), ONE_DASH,
 254               &General_options::add_to_rpath),
 255   GENERAL_NOARG('\0', "eh-frame-hdr", N_("Create exception frame header"),
 256                 NULL, TWO_DASHES, &General_options::create_eh_frame_hdr),
 257   GENERAL_NOARG('\0', "shared", N_("Generate shared library"),
 258                 NULL, ONE_DASH, &General_options::set_shared),
 259   GENERAL_NOARG('\0', "static", N_("Do not link against shared libraries"),
 260                 NULL, ONE_DASH, &General_options::set_static),
 261   POSDEP_NOARG('\0', "as-needed",
 262                N_("Only set DT_NEEDED for dynamic libs if used"),
 263                NULL, TWO_DASHES, &Position_dependent_options::set_as_needed),
 264   POSDEP_NOARG('\0', "no-as-needed",
 265                N_("Always DT_NEEDED for dynamic libs (default)"),
 266                NULL, TWO_DASHES, &Position_dependent_options::clear_as_needed),
 267   POSDEP_NOARG('\0', "whole-archive",
 268                N_("Include all archive contents"),
 269                NULL, TWO_DASHES,
 270                &Position_dependent_options::set_whole_archive),
 271   POSDEP_NOARG('\0', "no-whole-archive",
 272                N_("Include only needed archive contents"),
 273                NULL, TWO_DASHES,
 274                &Position_dependent_options::clear_whole_archive),
 275   SPECIAL('\0', "help", N_("Report usage information"), NULL,
 276           TWO_DASHES, &help)
 277 };
 278
 279 const int options::Command_line_options::options_size =
 280   sizeof (options) / sizeof (options[0]);
 281
 282 // The default values for the general options.
 283
 284 General_options::General_options()
 285   : export_dynamic_(false),
 286     dynamic_linker_(NULL),
 287     search_path_(),
 288     output_file_name_("a.out"),
 289     is_relocatable_(false),
 290     create_eh_frame_hdr_(false),
 291     rpath_(),
 292     is_shared_(false),
 293     is_static_(false)
 294 {
 295 }
 296
 297 // The default values for the position dependent options.
 298
 299 Position_dependent_options::Position_dependent_options()
 300   : do_static_search_(false),
 301     as_needed_(false),
 302     include_whole_archive_(false)
 303 {
 304 }
 305
 306 // Input_arguments methods.
 307
 308 // Add a file to the list.
 309
 310 void
 311 Input_arguments::add_file(const Input_file_argument& file)
 312 {
 313   if (!this->in_group_)
 314     this->input_argument_list_.push_back(Input_argument(file));
 315   else
 316     {
 317       gold_assert(!this->input_argument_list_.empty());
 318       gold_assert(this->input_argument_list_.back().is_group());
 319       this->input_argument_list_.back().group()->add_file(file);
 320     }
 321 }
 322
 323 // Start a group.
 324
 325 void
 326 Input_arguments::start_group()
 327 {
 328   gold_assert(!this->in_group_);
 329   Input_file_group* group = new Input_file_group();
 330   this->input_argument_list_.push_back(Input_argument(group));
 331   this->in_group_ = true;
 332 }
 333
 334 // End a group.
 335
 336 void
 337 Input_arguments::end_group()
 338 {
 339   gold_assert(this->in_group_);
 340   this->in_group_ = false;
 341 }
 342
 343 // Command_line options.
 344
 345 Command_line::Command_line()
 346   : options_(), position_options_(), inputs_()
 347 {
 348 }
 349
 350 // Process the command line options.
 351
 352 void
 353 Command_line::process(int argc, char** argv)
 354 {
 355   const int options_size = options::Command_line_options::options_size;
 356   const options::One_option* options =
 357     options::Command_line_options::options;
 358   bool no_more_options = false;
 359   int i = 0;
 360   while (i < argc)
 361     {
 362       if (argv[i][0] != '-' || no_more_options)
 363         {
 364           this->add_file(argv[i], false);
 365           ++i;
 366           continue;
 367         }
 368
 369       // Option starting with '-'.
 370       int dashes = 1;
 371       if (argv[i][1] == '-')
 372         {
 373           dashes = 2;
 374           if (argv[i][2] == '\0')
 375             {
 376               no_more_options = true;
 377               continue;
 378             }
 379         }
 380
 381       // Look for a long option match.
 382       char* opt = argv[i] + dashes;
 383       char first = opt[0];
 384       int skiparg = 0;
 385       char* arg = strchr(opt, '=');
 386       if (arg != NULL)
 387         *arg = '\0';
 388       else if (i + 1 < argc)
 389         {
 390           arg = argv[i + 1];
 391           skiparg = 1;
 392         }
 393
 394       int j;
 395       for (j = 0; j < options_size; ++j)
 396         {
 397           if (options[j].long_option != NULL
 398               && (dashes == 2
 399                   || (options[j].dash
 400                       != options::One_option::EXACTLY_TWO_DASHES))
 401               && first == options[j].long_option[0]
 402               && strcmp(opt, options[j].long_option) == 0)
 403             {
 404               if (options[j].special)
 405                 i += options[j].special(argc - 1, argv + i, opt, this);
 406               else
 407                 {
 408                   if (!options[j].takes_argument())
 409                     {
 410                       arg = NULL;
 411                       skiparg = 0;
 412                     }
 413                   else
 414                     {
 415                       if (arg == NULL)
 416                         this->usage(_("missing argument"), argv[i]);
 417                     }
 418                   this->apply_option(options[j], arg);
 419                   i += skiparg + 1;
 420                 }
 421               break;
 422             }
 423         }
 424       if (j < options_size)
 425         continue;
 426
 427       // If we saw two dashes, we need to see a long option.
 428       if (dashes == 2)
 429         this->usage(_("unknown option"), argv[i]);
 430
 431       // Look for a short option match.  There may be more than one
 432       // short option in a given argument.
 433       bool done = false;
 434       char* s = argv[i] + 1;
 435       ++i;
 436       while (*s != '\0' && !done)
 437         {
 438           char opt = *s;
 439           int j;
 440           for (j = 0; j < options_size; ++j)
 441             {
 442               if (options[j].short_option == opt)
 443                 {
 444                   if (options[j].special)
 445                     {
 446                       // Undo the argument skip done above.
 447                       --i;
 448                       i += options[j].special(argc - i, argv + i, s, this);
 449                       done = true;
 450                     }
 451                   else
 452                     {
 453                       arg = NULL;
 454                       if (options[j].takes_argument())
 455                         {
 456                           if (s[1] != '\0')
 457                             {
 458                               arg = s + 1;
 459                               done = true;
 460                             }
 461                           else if (i < argc)
 462                             {
 463                               arg = argv[i];
 464                               ++i;
 465                             }
 466                           else
 467                             this->usage(_("missing argument"), opt);
 468                         }
 469                       this->apply_option(options[j], arg);
 470                     }
 471                   break;
 472                 }
 473             }
 474
 475           if (j >= options_size)
 476             this->usage(_("unknown option"), *s);
 477
 478           ++s;
 479         }
 480     }
 481
 482   if (this->inputs_.in_group())
 483     {
 484       fprintf(stderr, _("%s: missing group end"), program_name);
 485       this->usage();
 486     }
 487
 488   // FIXME: We should only do this when configured in native mode.
 489   this->options_.add_to_search_path("/lib");
 490   this->options_.add_to_search_path("/usr/lib");
 491 }
 492
 493 // Apply a command line option.
 494
 495 void
 496 Command_line::apply_option(const options::One_option& opt,
 497                            const char* arg)
 498 {
 499   if (arg == NULL)
 500     {
 501       if (opt.general_noarg)
 502         (this->options_.*(opt.general_noarg))();
 503       else if (opt.dependent_noarg)
 504         (this->position_options_.*(opt.dependent_noarg))();
 505       else
 506         gold_unreachable();
 507     }
 508   else
 509     {
 510       if (opt.general_arg)
 511         (this->options_.*(opt.general_arg))(arg);
 512       else if (opt.dependent_arg)
 513         (this->position_options_.*(opt.dependent_arg))(arg);
 514       else
 515         gold_unreachable();
 516     }
 517 }
 518
 519 // Add an input file or library.
 520
 521 void
 522 Command_line::add_file(const char* name, bool is_lib)
 523 {
 524   Input_file_argument file(name, is_lib, this->position_options_);
 525   this->inputs_.add_file(file);
 526 }
 527
 528 // Handle the -l option, which requires special treatment.
 529
 530 int
 531 Command_line::process_l_option(int argc, char** argv, char* arg)
 532 {
 533   int ret;
 534   const char* libname;
 535   if (arg[1] != '\0')
 536     {
 537       ret = 1;
 538       libname = arg + 1;
 539     }
 540   else if (argc > 1)
 541     {
 542       ret = 2;
 543       libname = argv[argc + 1];
 544     }
 545   else
 546     this->usage(_("missing argument"), arg);
 547
 548   this->add_file(libname, true);
 549
 550   return ret;
 551 }
 552
 553 // Handle the --start-group option.
 554
 555 void
 556 Command_line::start_group(const char* arg)
 557 {
 558   if (this->inputs_.in_group())
 559     this->usage(_("may not nest groups"), arg);
 560   this->inputs_.start_group();
 561 }
 562
 563 // Handle the --end-group option.
 564
 565 void
 566 Command_line::end_group(const char* arg)
 567 {
 568   if (!this->inputs_.in_group())
 569     this->usage(_("group end without group start"), arg);
 570   this->inputs_.end_group();
 571 }
 572
 573 // Report a usage error.  */
 574
 575 void
 576 Command_line::usage()
 577 {
 578   fprintf(stderr,
 579           _("%s: use the --help option for usage information\n"),
 580           program_name);
 581   gold_exit(false);
 582 }
 583
 584 void
 585 Command_line::usage(const char* msg, const char *opt)
 586 {
 587   fprintf(stderr,
 588           _("%s: %s: %s\n"),
 589           program_name, opt, msg);
 590   this->usage();
 591 }
 592
 593 void
 594 Command_line::usage(const char* msg, char opt)
 595 {
 596   fprintf(stderr,
 597           _("%s: -%c: %s\n"),
 598           program_name, opt, msg);
 599   this->usage();
 600 }
 601
 602 } // End namespace gold.