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 // The information we keep for a single command line option.
   9
  10 struct gold::options::One_option
  11 {
  12   // The single character option name, or '\0' if this is only a long
  13   // option.
  14   char short_option;
  15
  16   // The long option name, or NULL if this is only a short option.
  17   const char* long_option;
  18
  19   // Description of the option for --help output, or NULL if there is none.
  20   const char* doc;
  21
  22   // How to print the option name in --help output, or NULL to use the
  23   // default.
  24   const char* help_output;
  25
  26   // Long option dash control.  This is ignored if long_option is
  27   // NULL.
  28   enum
  29     {
  30       // Long option normally takes one dash; two dashes are also
  31       // accepted.
  32       ONE_DASH,
  33       // Long option normally takes two dashes; one dash is also
  34       // accepted.
  35       TWO_DASHES,
  36       // Long option always takes two dashes.
  37       EXACTLY_TWO_DASHES
  38     } dash;
  39
  40   // Function for special handling, or NULL.  Returns the number of
  41   // arguments to skip.  This will normally be at least 1, but it may
  42   // be 0 if this function changes *argv.  ARG points to the location
  43   // in *ARGV where the option starts, which may be helpful for a
  44   // short option.
  45   int (*special)(int argc, char** argv, char *arg, gold::Command_line*);
  46
  47   // If this is a position independent option which does not take an
  48   // argument, this is the member function to call to record it.
  49   void (gold::General_options::*general_noarg)();
  50
  51   // If this is a position independent function which takes an
  52   // argument, this is the member function to call to record it.
  53   void (gold::General_options::*general_arg)(const char*);
  54
  55   // If this is a position dependent option which does not take an
  56   // argument, this is the member function to call to record it.
  57   void (gold::Position_dependent_options::*dependent_noarg)();
  58
  59   // If this is a position dependent option which takes an argument,
  60   // this is the member function to record it.
  61   void (gold::Position_dependent_options::*dependent_arg)(const char*);
  62
  63   // Return whether this option takes an argument.
  64   bool
  65   takes_argument() const
  66   { return this->general_arg != NULL || this->dependent_arg != NULL; }
  67 };
  68
  69 class gold::options::Command_line_options
  70 {
  71  public:
  72   static const One_option options[];
  73   static const int options_size;
  74 };
  75
  76 namespace
  77 {
  78
  79 // Report usage information for ld --help, and exit.
  80
  81 int
  82 help(int, char**, char*, gold::Command_line*)
  83 {
  84   printf(_("Usage: %s [options] file...\nOptions:\n"), gold::program_name);
  85
  86   const int options_size = gold::options::Command_line_options::options_size;
  87   const gold::options::One_option* options =
  88     gold::options::Command_line_options::options;
  89   for (int i = 0; i < options_size; ++i)
  90     {
  91       if (options[i].doc == NULL)
  92         continue;
  93
  94       printf("  ");
  95       int len = 2;
  96       bool comma = false;
  97
  98       int j = i;
  99       do
 100         {
 101           if (options[j].help_output != NULL)
 102             {
 103               if (comma)
 104                 {
 105                   printf(", ");
 106                   len += 2;
 107                 }
 108               printf(options[j].help_output);
 109               len += std::strlen(options[i].help_output);
 110             }
 111           else
 112             {
 113               if (options[j].short_option != '\0')
 114                 {
 115                   if (comma)
 116                     {
 117                       printf(", ");
 118                       len += 2;
 119                     }
 120                   printf("-%c", options[j].short_option);
 121                   len += 2;
 122                 }
 123
 124               if (options[j].long_option != NULL)
 125                 {
 126                   if (comma)
 127                     {
 128                       printf(", ");
 129                       len += 2;
 130                     }
 131                   if (options[j].dash == gold::options::One_option::ONE_DASH)
 132                     {
 133                       printf("-");
 134                       ++len;
 135                     }
 136                   else
 137                     {
 138                       printf("--");
 139                       len += 2;
 140                     }
 141                   printf("%s", options[j].long_option);
 142                   len += std::strlen(options[j].long_option);
 143                 }
 144             }
 145           ++j;
 146         }
 147       while (j < options_size && options[j].doc == NULL);
 148
 149       if (len > 30)
 150         {
 151           printf("\n");
 152           len = 0;
 153         }
 154       for (; len < 30; ++len)
 155         std::putchar(' ');
 156
 157       std::puts(options[i].doc);
 158     }
 159
 160   gold::gold_exit(true);
 161
 162   return 0;
 163 }
 164
 165 } // End empty namespace.
 166
 167 // Helper macros used to specify the options.  We could also do this
 168 // using constructors, but then g++ would generate code to initialize
 169 // the array.  We want the array to be initialized statically so that
 170 // we get better startup time.
 171
 172 #define GENERAL_NOARG(short_option, long_option, doc, help, dash, func) \
 173   { short_option, long_option, doc, help, gold::options::One_option::dash, \
 174       NULL, func, NULL, NULL, NULL }
 175 #define GENERAL_ARG(short_option, long_option, doc, help, dash, func)   \
 176   { short_option, long_option, doc, help, gold::options::One_option::dash, \
 177       NULL, NULL, func, NULL, NULL }
 178 #define POSDEP_NOARG(short_option, long_option, doc, help, dash, func)  \
 179   { short_option, long_option, doc, help, gold::options::One_option::dash, \
 180       NULL,  NULL, NULL, func, NULL }
 181 #define POSDEP_ARG(short_option, long_option, doc, help, dash, func)    \
 182   { short_option, long_option, doc, help, gold::options::One_option::dash, \
 183       NULL, NULL, NULL, NULL, func }
 184 #define SPECIAL(short_option, long_option, doc, help, dash, func)       \
 185   { short_option, long_option, doc, help, gold::options::One_option::dash, \
 186       func, NULL, NULL, NULL, NULL }
 187
 188 // Here is the actual list of options which we accept.
 189
 190 const gold::options::One_option
 191 gold::options::Command_line_options::options[] =
 192 {
 193   GENERAL_ARG('L', "library-path", N_("Add directory to search path"),
 194               N_("-L DIR, --library-path DIR"), TWO_DASHES,
 195               &gold::General_options::add_to_search_path),
 196   GENERAL_NOARG('r', NULL, N_("Generate relocatable output"), NULL,
 197                 ONE_DASH, &gold::General_options::set_relocatable),
 198   GENERAL_NOARG('\0', "static", N_("Do not link against shared libraries"),
 199                 NULL, ONE_DASH, &gold::General_options::set_static),
 200   SPECIAL('\0', "help", N_("Report usage information"), NULL,
 201           TWO_DASHES, &help)
 202 };
 203
 204 const int gold::options::Command_line_options::options_size =
 205   sizeof (options) / sizeof (options[0]);
 206
 207 // The default values for the general options.
 208
 209 gold::General_options::General_options()
 210   : is_relocatable_(false)
 211 {
 212 }
 213
 214 // The default values for the position dependent options.
 215
 216 gold::Position_dependent_options::Position_dependent_options()
 217   : do_static_search_(false)
 218 {
 219 }
 220
 221 // Construct a Command_line.
 222
 223 gold::Command_line::Command_line()
 224 {
 225 }
 226
 227 // Process the command line options.
 228
 229 void
 230 gold::Command_line::process(int argc, char** argv)
 231 {
 232   const int options_size = gold::options::Command_line_options::options_size;
 233   const gold::options::One_option* options =
 234     gold::options::Command_line_options::options;
 235   bool no_more_options = false;
 236   int i = 0;
 237   while (i < argc)
 238     {
 239       if (argv[i][0] != '-' || no_more_options)
 240         {
 241           this->inputs_.push_back(Input_argument(argv[i],
 242                                                  this->position_options_));
 243           ++i;
 244           continue;
 245         }
 246
 247       // Option starting with '-'.
 248       int dashes = 1;
 249       if (argv[i][1] == '-')
 250         {
 251           dashes = 2;
 252           if (argv[i][2] == '\0')
 253             {
 254               no_more_options = true;
 255               continue;
 256             }
 257         }
 258
 259       // Look for a long option match.
 260       char* opt = argv[i] + dashes;
 261       char first = opt[0];
 262       int skiparg = 0;
 263       char* arg = strchr(opt, '=');
 264       if (arg != NULL)
 265         *arg = '\0';
 266       else if (i + 1 < argc)
 267         {
 268           arg = argv[i + 1];
 269           skiparg = 1;
 270         }
 271
 272       int j;
 273       for (j = 0; j < options_size; ++j)
 274         {
 275           if (options[j].long_option != NULL
 276               && (dashes == 2
 277                   || (options[j].dash
 278                       != gold::options::One_option::EXACTLY_TWO_DASHES))
 279               && first == options[j].long_option[0]
 280               && strcmp(opt, options[j].long_option) == 0)
 281             {
 282               if (options[j].special)
 283                 i += options[j].special(argc - 1, argv + i, opt, this);
 284               else
 285                 {
 286                   if (!options[j].takes_argument())
 287                     {
 288                       arg = NULL;
 289                       skiparg = 0;
 290                     }
 291                   else
 292                     {
 293                       if (arg == NULL)
 294                         this->usage(_("missing argument"), argv[i]);
 295                     }
 296                   this->apply_option(options[j], arg);
 297                   i += skiparg + 1;
 298                 }
 299               break;
 300             }
 301         }
 302       if (j < options_size)
 303         continue;
 304
 305       // If we saw two dashes, we need to see a long option.
 306       if (dashes == 2)
 307         this->usage(_("unknown option"), argv[i]);
 308
 309       // Look for a short option match.  There may be more than one
 310       // short option in a given argument.
 311       bool done = false;
 312       char* s = argv[i] + 1;
 313       ++i;
 314       while (*s != '\0' && !done)
 315         {
 316           char opt = *s;
 317           int j;
 318           for (j = 0; j < options_size; ++j)
 319             {
 320               if (options[j].short_option == opt)
 321                 {
 322                   if (options[j].special)
 323                     {
 324                       // Undo the argument skip done above.
 325                       --i;
 326                       i += options[j].special(argc - i, argv + i, s, this);
 327                       done = true;
 328                     }
 329                   else
 330                     {
 331                       arg = NULL;
 332                       if (options[j].takes_argument())
 333                         {
 334                           if (s[1] != '\0')
 335                             {
 336                               arg = s + 1;
 337                               done = true;
 338                             }
 339                           else if (i < argc)
 340                             {
 341                               arg = argv[i];
 342                               ++i;
 343                             }
 344                           else
 345                             this->usage(_("missing argument"), opt);
 346                         }
 347                       this->apply_option(options[j], arg);
 348                     }
 349                   break;
 350                 }
 351             }
 352
 353           if (j >= options_size)
 354             this->usage(_("unknown option"), *s);
 355
 356           ++s;
 357         }
 358     }
 359 }
 360
 361 // Apply a command line option.
 362
 363 void
 364 gold::Command_line::apply_option(const gold::options::One_option& opt,
 365                                  const char* arg)
 366 {
 367   if (arg == NULL)
 368     {
 369       if (opt.general_noarg)
 370         (this->options_.*(opt.general_noarg))();
 371       else if (opt.dependent_noarg)
 372         (this->position_options_.*(opt.dependent_noarg))();
 373       else
 374         gold::gold_unreachable();
 375     }
 376   else
 377     {
 378       if (opt.general_arg)
 379         (this->options_.*(opt.general_arg))(arg);
 380       else if (opt.dependent_arg)
 381         (this->position_options_.*(opt.dependent_arg))(arg);
 382       else
 383         gold::gold_unreachable();
 384     }
 385 }
 386
 387 // Report a usage error.  */
 388
 389 void
 390 gold::Command_line::usage()
 391 {
 392   fprintf(stderr,
 393           _("%s: use the --help option for usage information\n"),
 394           gold::program_name);
 395   gold::gold_exit(false);
 396 }
 397
 398 void
 399 gold::Command_line::usage(const char* msg, const char *opt)
 400 {
 401   fprintf(stderr,
 402           _("%s: %s: %s\n"),
 403           gold::program_name, opt, msg);
 404   this->usage();
 405 }
 406
 407 void
 408 gold::Command_line::usage(const char* msg, char opt)
 409 {
 410   fprintf(stderr,
 411           _("%s: -%c: %s\n"),
 412           gold::program_name, opt, msg);
 413   this->usage();
 414 }