ld/plugin.c

   1 /* Plugin control for the GNU linker.
   2    Copyright 2010, 2011 Free Software Foundation, Inc.
   3
   4    This file is part of the GNU Binutils.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  19    MA 02110-1301, USA.  */
  20
  21 #include "sysdep.h"
  22 #include "libiberty.h"
  23 #include "bfd.h"
  24 #include "bfdlink.h"
  25 #include "bfdver.h"
  26 #include "ld.h"
  27 #include "ldmain.h"
  28 #include "ldmisc.h"
  29 #include "ldexp.h"
  30 #include "ldlang.h"
  31 #include "ldfile.h"
  32 #include "plugin.h"
  33 #include "plugin-api.h"
  34 #include "elf-bfd.h"
  35 #include "libbfd.h"
  36 #if !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H)
  37 #include <windows.h>
  38 #endif
  39
  40 /* Report plugin symbols.  */
  41 bfd_boolean report_plugin_symbols;
  42
  43 /* The suffix to append to the name of the real (claimed) object file
  44    when generating a dummy BFD to hold the IR symbols sent from the
  45    plugin.  For cosmetic use only; appears in maps, crefs etc.  */
  46 #define IRONLY_SUFFIX " (symbol from plugin)"
  47
  48 /* Stores a single argument passed to a plugin.  */
  49 typedef struct plugin_arg
  50 {
  51   struct plugin_arg *next;
  52   const char *arg;
  53 } plugin_arg_t;
  54
  55 /* Holds all details of a single plugin.  */
  56 typedef struct plugin
  57 {
  58   /* Next on the list of plugins, or NULL at end of chain.  */
  59   struct plugin *next;
  60   /* The argument string given to --plugin.  */
  61   const char *name;
  62   /* The shared library handle returned by dlopen.  */
  63   void *dlhandle;
  64   /* The list of argument string given to --plugin-opt.  */
  65   plugin_arg_t *args;
  66   /* Number of args in the list, for convenience.  */
  67   size_t n_args;
  68   /* The plugin's event handlers.  */
  69   ld_plugin_claim_file_handler claim_file_handler;
  70   ld_plugin_all_symbols_read_handler all_symbols_read_handler;
  71   ld_plugin_cleanup_handler cleanup_handler;
  72   /* TRUE if the cleanup handlers have been called.  */
  73   bfd_boolean cleanup_done;
  74 } plugin_t;
  75
  76 /* The master list of all plugins.  */
  77 static plugin_t *plugins_list = NULL;
  78
  79 /* We keep a tail pointer for easy linking on the end.  */
  80 static plugin_t **plugins_tail_chain_ptr = &plugins_list;
  81
  82 /* The last plugin added to the list, for receiving args.  */
  83 static plugin_t *last_plugin = NULL;
  84
  85 /* The tail of the arg chain of the last plugin added to the list.  */
  86 static plugin_arg_t **last_plugin_args_tail_chain_ptr = NULL;
  87
  88 /* The plugin which is currently having a callback executed.  */
  89 static plugin_t *called_plugin = NULL;
  90
  91 /* Last plugin to cause an error, if any.  */
  92 static const char *error_plugin = NULL;
  93
  94 /* State of linker "notice" interface before we poked at it.  */
  95 static bfd_boolean orig_notice_all;
  96
  97 /* Original linker callbacks, and the plugin version.  */
  98 static const struct bfd_link_callbacks *orig_callbacks;
  99 static struct bfd_link_callbacks plugin_callbacks;
 100
 101 /* Set at all symbols read time, to avoid recursively offering the plugin
 102    its own newly-added input files and libs to claim.  */
 103 bfd_boolean no_more_claiming = FALSE;
 104
 105 /* List of tags to set in the constant leading part of the tv array. */
 106 static const enum ld_plugin_tag tv_header_tags[] =
 107 {
 108   LDPT_MESSAGE,
 109   LDPT_API_VERSION,
 110   LDPT_GNU_LD_VERSION,
 111   LDPT_LINKER_OUTPUT,
 112   LDPT_OUTPUT_NAME,
 113   LDPT_REGISTER_CLAIM_FILE_HOOK,
 114   LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK,
 115   LDPT_REGISTER_CLEANUP_HOOK,
 116   LDPT_ADD_SYMBOLS,
 117   LDPT_GET_INPUT_FILE,
 118   LDPT_RELEASE_INPUT_FILE,
 119   LDPT_GET_SYMBOLS,
 120   LDPT_ADD_INPUT_FILE,
 121   LDPT_ADD_INPUT_LIBRARY,
 122   LDPT_SET_EXTRA_LIBRARY_PATH
 123 };
 124
 125 /* How many entries in the constant leading part of the tv array.  */
 126 static const size_t tv_header_size = ARRAY_SIZE (tv_header_tags);
 127
 128 /* Forward references.  */
 129 static bfd_boolean plugin_notice (struct bfd_link_info *,
 130                                   struct bfd_link_hash_entry *, bfd *,
 131                                   asection *, bfd_vma, flagword, const char *);
 132
 133 #if !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H)
 134
 135 #define RTLD_NOW 0      /* Dummy value.  */
 136
 137 static void *
 138 dlopen (const char *file, int mode ATTRIBUTE_UNUSED)
 139 {
 140   return LoadLibrary (file);
 141 }
 142
 143 static void *
 144 dlsym (void *handle, const char *name)
 145 {
 146   return GetProcAddress (handle, name);
 147 }
 148
 149 static int
 150 dlclose (void *handle)
 151 {
 152   FreeLibrary (handle);
 153   return 0;
 154 }
 155
 156 #endif /* !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H)  */
 157
 158 /* Helper function for exiting with error status.  */
 159 static int
 160 set_plugin_error (const char *plugin)
 161 {
 162   error_plugin = plugin;
 163   return -1;
 164 }
 165
 166 /* Test if an error occurred.  */
 167 static bfd_boolean
 168 plugin_error_p (void)
 169 {
 170   return error_plugin != NULL;
 171 }
 172
 173 /* Return name of plugin which caused an error if any.  */
 174 const char *
 175 plugin_error_plugin (void)
 176 {
 177   return error_plugin ? error_plugin : _("<no plugin>");
 178 }
 179
 180 /* Handle -plugin arg: find and load plugin, or return error.  */
 181 int
 182 plugin_opt_plugin (const char *plugin)
 183 {
 184   plugin_t *newplug;
 185
 186   newplug = xmalloc (sizeof *newplug);
 187   memset (newplug, 0, sizeof *newplug);
 188   newplug->name = plugin;
 189   newplug->dlhandle = dlopen (plugin, RTLD_NOW);
 190   if (!newplug->dlhandle)
 191     return set_plugin_error (plugin);
 192
 193   /* Chain on end, so when we run list it is in command-line order.  */
 194   *plugins_tail_chain_ptr = newplug;
 195   plugins_tail_chain_ptr = &newplug->next;
 196
 197   /* Record it as current plugin for receiving args.  */
 198   last_plugin = newplug;
 199   last_plugin_args_tail_chain_ptr = &newplug->args;
 200   return 0;
 201 }
 202
 203 /* Accumulate option arguments for last-loaded plugin, or return
 204    error if none.  */
 205 int
 206 plugin_opt_plugin_arg (const char *arg)
 207 {
 208   plugin_arg_t *newarg;
 209
 210   if (!last_plugin)
 211     return set_plugin_error (_("<no plugin>"));
 212
 213   newarg = xmalloc (sizeof *newarg);
 214   newarg->arg = arg;
 215   newarg->next = NULL;
 216
 217   /* Chain on end to preserve command-line order.  */
 218   *last_plugin_args_tail_chain_ptr = newarg;
 219   last_plugin_args_tail_chain_ptr = &newarg->next;
 220   last_plugin->n_args++;
 221   return 0;
 222 }
 223
 224 /* Create a dummy BFD.  */
 225 bfd *
 226 plugin_get_ir_dummy_bfd (const char *name, bfd *srctemplate)
 227 {
 228   bfd *abfd;
 229
 230   bfd_use_reserved_id = 1;
 231   abfd = bfd_create (concat (name, IRONLY_SUFFIX, (const char *) NULL),
 232                      srctemplate);
 233   if (abfd != NULL)
 234     {
 235       abfd->flags |= BFD_LINKER_CREATED | BFD_PLUGIN;
 236       bfd_set_arch_info (abfd, bfd_get_arch_info (srctemplate));
 237       bfd_set_gp_size (abfd, bfd_get_gp_size (srctemplate));
 238       if (bfd_make_writable (abfd)
 239           && bfd_copy_private_bfd_data (srctemplate, abfd))
 240         {
 241           flagword flags;
 242
 243           /* Create sections to own the symbols.  */
 244           flags = (SEC_CODE | SEC_HAS_CONTENTS | SEC_READONLY
 245                    | SEC_ALLOC | SEC_LOAD | SEC_KEEP | SEC_EXCLUDE);
 246           if (bfd_make_section_anyway_with_flags (abfd, ".text", flags))
 247             return abfd;
 248         }
 249     }
 250   einfo (_("could not create dummy IR bfd: %F%E\n"));
 251   return NULL;
 252 }
 253
 254 /* Check if the BFD passed in is an IR dummy object file.  */
 255 static bfd_boolean
 256 is_ir_dummy_bfd (const bfd *abfd)
 257 {
 258   /* ABFD can sometimes legitimately be NULL, e.g. when called from one
 259      of the linker callbacks for a symbol in the *ABS* or *UND* sections.
 260      Likewise, the usrdata field may be NULL if ABFD was added by the
 261      backend without a corresponding input statement, as happens e.g.
 262      when processing DT_NEEDED dependencies.  */
 263   return (abfd
 264           && abfd->usrdata
 265           && ((lang_input_statement_type *)(abfd->usrdata))->claimed);
 266 }
 267
 268 /* Helpers to convert between BFD and GOLD symbol formats.  */
 269 static enum ld_plugin_status
 270 asymbol_from_plugin_symbol (bfd *abfd, asymbol *asym,
 271                             const struct ld_plugin_symbol *ldsym)
 272 {
 273   flagword flags = BSF_NO_FLAGS;
 274   struct bfd_section *section;
 275
 276   asym->the_bfd = abfd;
 277   asym->name = (ldsym->version
 278                 ? concat (ldsym->name, "@", ldsym->version, (const char *) NULL)
 279                 : ldsym->name);
 280   asym->value = 0;
 281   switch (ldsym->def)
 282     {
 283     case LDPK_WEAKDEF:
 284       flags = BSF_WEAK;
 285       /* FALLTHRU */
 286     case LDPK_DEF:
 287       flags |= BSF_GLOBAL;
 288       section = bfd_get_section_by_name (abfd, ".text");
 289       break;
 290
 291     case LDPK_WEAKUNDEF:
 292       flags = BSF_WEAK;
 293       /* FALLTHRU */
 294     case LDPK_UNDEF:
 295       section = bfd_und_section_ptr;
 296       break;
 297
 298     case LDPK_COMMON:
 299       flags = BSF_GLOBAL;
 300       section = bfd_com_section_ptr;
 301       asym->value = ldsym->size;
 302       /* For ELF targets, set alignment of common symbol to 1.  */
 303       if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)
 304         {
 305           ((elf_symbol_type *) asym)->internal_elf_sym.st_shndx = SHN_COMMON;
 306           ((elf_symbol_type *) asym)->internal_elf_sym.st_value = 1;
 307         }
 308       break;
 309
 310     default:
 311       return LDPS_ERR;
 312     }
 313   asym->flags = flags;
 314   asym->section = section;
 315
 316   /* Visibility only applies on ELF targets.  */
 317   if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)
 318     {
 319       elf_symbol_type *elfsym = elf_symbol_from (abfd, asym);
 320       unsigned char visibility;
 321
 322       if (!elfsym)
 323         einfo (_("%P%F: %s: non-ELF symbol in ELF BFD!\n"), asym->name);
 324       switch (ldsym->visibility)
 325         {
 326         default:
 327           einfo (_("%P%F: unknown ELF symbol visibility: %d!\n"),
 328                  ldsym->visibility);
 329         case LDPV_DEFAULT:
 330           visibility = STV_DEFAULT;
 331           break;
 332         case LDPV_PROTECTED:
 333           visibility = STV_PROTECTED;
 334           break;
 335         case LDPV_INTERNAL:
 336           visibility = STV_INTERNAL;
 337           break;
 338         case LDPV_HIDDEN:
 339           visibility = STV_HIDDEN;
 340           break;
 341         }
 342       elfsym->internal_elf_sym.st_other
 343         = (visibility | (elfsym->internal_elf_sym.st_other
 344                          & ~ELF_ST_VISIBILITY (-1)));
 345     }
 346
 347   return LDPS_OK;
 348 }
 349
 350 /* Register a claim-file handler.  */
 351 static enum ld_plugin_status
 352 register_claim_file (ld_plugin_claim_file_handler handler)
 353 {
 354   ASSERT (called_plugin);
 355   called_plugin->claim_file_handler = handler;
 356   return LDPS_OK;
 357 }
 358
 359 /* Register an all-symbols-read handler.  */
 360 static enum ld_plugin_status
 361 register_all_symbols_read (ld_plugin_all_symbols_read_handler handler)
 362 {
 363   ASSERT (called_plugin);
 364   called_plugin->all_symbols_read_handler = handler;
 365   return LDPS_OK;
 366 }
 367
 368 /* Register a cleanup handler.  */
 369 static enum ld_plugin_status
 370 register_cleanup (ld_plugin_cleanup_handler handler)
 371 {
 372   ASSERT (called_plugin);
 373   called_plugin->cleanup_handler = handler;
 374   return LDPS_OK;
 375 }
 376
 377 /* Add symbols from a plugin-claimed input file.  */
 378 static enum ld_plugin_status
 379 add_symbols (void *handle, int nsyms, const struct ld_plugin_symbol *syms)
 380 {
 381   asymbol **symptrs;
 382   bfd *abfd = handle;
 383   int n;
 384
 385   ASSERT (called_plugin);
 386   symptrs = xmalloc (nsyms * sizeof *symptrs);
 387   for (n = 0; n < nsyms; n++)
 388     {
 389       enum ld_plugin_status rv;
 390       asymbol *bfdsym;
 391
 392       if (syms[n].comdat_key)
 393         {
 394           struct already_linked linked;
 395           linked.comdat_key = xstrdup (syms[n].comdat_key);
 396           linked.u.abfd = abfd;
 397           bfd_section_already_linked (abfd, &linked, &link_info);
 398         }
 399       bfdsym = bfd_make_empty_symbol (abfd);
 400       symptrs[n] = bfdsym;
 401       rv = asymbol_from_plugin_symbol (abfd, bfdsym, syms + n);
 402       if (rv != LDPS_OK)
 403         return rv;
 404     }
 405   bfd_set_symtab (abfd, symptrs, nsyms);
 406   return LDPS_OK;
 407 }
 408
 409 /* Get the input file information with an open (possibly re-opened)
 410    file descriptor.  */
 411 static enum ld_plugin_status
 412 get_input_file (const void *handle, struct ld_plugin_input_file *file)
 413 {
 414   ASSERT (called_plugin);
 415   handle = handle;
 416   file = file;
 417   return LDPS_ERR;
 418 }
 419
 420 /* Release the input file.  */
 421 static enum ld_plugin_status
 422 release_input_file (const void *handle)
 423 {
 424   ASSERT (called_plugin);
 425   handle = handle;
 426   return LDPS_ERR;
 427 }
 428
 429 /* Return TRUE if a defined symbol might be reachable from outside the
 430    universe of claimed objects.  */
 431 static inline bfd_boolean
 432 is_visible_from_outside (struct ld_plugin_symbol *lsym, asection *section,
 433                          struct bfd_link_hash_entry *blhe)
 434 {
 435   struct bfd_sym_chain *sym;
 436
 437   /* Section's owner may be NULL if it is the absolute
 438      section, fortunately is_ir_dummy_bfd handles that.  */
 439   if (!is_ir_dummy_bfd (section->owner))
 440     return TRUE;
 441   if (link_info.relocatable)
 442     return TRUE;
 443   if (link_info.export_dynamic || link_info.shared)
 444     {
 445       /* Only ELF symbols really have visibility.  */
 446       if (bfd_get_flavour (link_info.output_bfd) == bfd_target_elf_flavour)
 447         {
 448           struct elf_link_hash_entry *el = (struct elf_link_hash_entry *)blhe;
 449           int vis = ELF_ST_VISIBILITY (el->other);
 450           return vis == STV_DEFAULT || vis == STV_PROTECTED;
 451         }
 452       /* On non-ELF targets, we can safely make inferences by considering
 453          what visibility the plugin would have liked to apply when it first
 454          sent us the symbol.  During ELF symbol processing, visibility only
 455          ever becomes more restrictive, not less, when symbols are merged,
 456          so this is a conservative estimate; it may give false positives,
 457          declaring something visible from outside when it in fact would
 458          not have been, but this will only lead to missed optimisation
 459          opportunities during LTRANS at worst; it will not give false
 460          negatives, which can lead to the disastrous conclusion that the
 461          related symbol is IRONLY.  (See GCC PR46319 for an example.)  */
 462       return (lsym->visibility == LDPV_DEFAULT
 463               || lsym->visibility == LDPV_PROTECTED);
 464     }
 465
 466   for (sym = &entry_symbol; sym != NULL; sym = sym->next)
 467     if (sym->name
 468         && strcmp (sym->name, blhe->root.string) == 0)
 469       return TRUE;
 470
 471   return FALSE;
 472 }
 473
 474 /* Get the symbol resolution info for a plugin-claimed input file.  */
 475 static enum ld_plugin_status
 476 get_symbols (const void *handle, int nsyms, struct ld_plugin_symbol *syms)
 477 {
 478   const bfd *abfd = handle;
 479   int n;
 480   ASSERT (called_plugin);
 481   for (n = 0; n < nsyms; n++)
 482     {
 483       struct bfd_link_hash_entry *blhe;
 484       bfd_boolean ironly;
 485       asection *owner_sec;
 486       if (syms[n].def != LDPK_UNDEF)
 487         blhe = bfd_link_hash_lookup (link_info.hash, syms[n].name,
 488                                      FALSE, FALSE, TRUE);
 489       else
 490         blhe = bfd_wrapped_link_hash_lookup (link_info.output_bfd, &link_info,
 491                                              syms[n].name, FALSE, FALSE, TRUE);
 492       if (!blhe)
 493         {
 494           syms[n].resolution = LDPR_UNKNOWN;
 495           goto report_symbol;
 496         }
 497
 498       /* Determine resolution from blhe type and symbol's original type.  */
 499       if (blhe->type == bfd_link_hash_undefined
 500           || blhe->type == bfd_link_hash_undefweak)
 501         {
 502           syms[n].resolution = LDPR_UNDEF;
 503           goto report_symbol;
 504         }
 505       if (blhe->type != bfd_link_hash_defined
 506           && blhe->type != bfd_link_hash_defweak
 507           && blhe->type != bfd_link_hash_common)
 508         {
 509           /* We should not have a new, indirect or warning symbol here.  */
 510           einfo ("%P%F: %s: plugin symbol table corrupt (sym type %d)\n",
 511                  called_plugin->name, blhe->type);
 512         }
 513
 514       /* Find out which section owns the symbol.  Since it's not undef,
 515          it must have an owner; if it's not a common symbol, both defs
 516          and weakdefs keep it in the same place. */
 517       owner_sec = (blhe->type == bfd_link_hash_common
 518                    ? blhe->u.c.p->section
 519                    : blhe->u.def.section);
 520
 521       /* We need to know if the sym is referenced from non-IR files.  Or
 522          even potentially-referenced, perhaps in a future final link if
 523          this is a partial one, perhaps dynamically at load-time if the
 524          symbol is externally visible.  */
 525       ironly = !(blhe->non_ir_ref
 526                  || is_visible_from_outside (&syms[n], owner_sec, blhe));
 527
 528       /* If it was originally undefined or common, then it has been
 529          resolved; determine how.  */
 530       if (syms[n].def == LDPK_UNDEF
 531           || syms[n].def == LDPK_WEAKUNDEF
 532           || syms[n].def == LDPK_COMMON)
 533         {
 534           if (owner_sec->owner == link_info.output_bfd)
 535             syms[n].resolution = LDPR_RESOLVED_EXEC;
 536           else if (owner_sec->owner == abfd)
 537             syms[n].resolution = (ironly
 538                                   ? LDPR_PREVAILING_DEF_IRONLY
 539                                   : LDPR_PREVAILING_DEF);
 540           else if (is_ir_dummy_bfd (owner_sec->owner))
 541             syms[n].resolution = LDPR_RESOLVED_IR;
 542           else if (owner_sec->owner != NULL
 543                    && (owner_sec->owner->flags & DYNAMIC) != 0)
 544             syms[n].resolution =  LDPR_RESOLVED_DYN;
 545           else
 546             syms[n].resolution = LDPR_RESOLVED_EXEC;
 547           goto report_symbol;
 548         }
 549
 550       /* Was originally def, or weakdef.  Does it prevail?  If the
 551          owner is the original dummy bfd that supplied it, then this
 552          is the definition that has prevailed.  */
 553       if (owner_sec->owner == link_info.output_bfd)
 554         syms[n].resolution = LDPR_PREEMPTED_REG;
 555       else if (owner_sec->owner == abfd)
 556         {
 557           syms[n].resolution = (ironly
 558                                 ? LDPR_PREVAILING_DEF_IRONLY
 559                                 : LDPR_PREVAILING_DEF);
 560           goto report_symbol;
 561         }
 562
 563       /* Was originally def, weakdef, or common, but has been pre-empted.  */
 564       syms[n].resolution = (is_ir_dummy_bfd (owner_sec->owner)
 565                             ? LDPR_PREEMPTED_IR
 566                             : LDPR_PREEMPTED_REG);
 567
 568     report_symbol:
 569       if (report_plugin_symbols)
 570         einfo (_("%P: %B: symbol `%s' "
 571                  "definition: %d, visibility: %d, resolution: %d\n"),
 572                abfd, syms[n].name,
 573                syms[n].def, syms[n].visibility, syms[n].resolution);
 574     }
 575   return LDPS_OK;
 576 }
 577
 578 /* Add a new (real) input file generated by a plugin.  */
 579 static enum ld_plugin_status
 580 add_input_file (const char *pathname)
 581 {
 582   ASSERT (called_plugin);
 583   if (!lang_add_input_file (xstrdup (pathname), lang_input_file_is_file_enum,
 584                             NULL))
 585     return LDPS_ERR;
 586   return LDPS_OK;
 587 }
 588
 589 /* Add a new (real) library required by a plugin.  */
 590 static enum ld_plugin_status
 591 add_input_library (const char *pathname)
 592 {
 593   ASSERT (called_plugin);
 594   if (!lang_add_input_file (xstrdup (pathname), lang_input_file_is_l_enum,
 595                             NULL))
 596     return LDPS_ERR;
 597   return LDPS_OK;
 598 }
 599
 600 /* Set the extra library path to be used by libraries added via
 601    add_input_library.  */
 602 static enum ld_plugin_status
 603 set_extra_library_path (const char *path)
 604 {
 605   ASSERT (called_plugin);
 606   ldfile_add_library_path (xstrdup (path), FALSE);
 607   return LDPS_OK;
 608 }
 609
 610 /* Issue a diagnostic message from a plugin.  */
 611 static enum ld_plugin_status
 612 message (int level, const char *format, ...)
 613 {
 614   va_list args;
 615   va_start (args, format);
 616
 617   switch (level)
 618     {
 619     case LDPL_INFO:
 620       vfinfo (stdout, format, args, FALSE);
 621       putchar ('\n');
 622       break;
 623     case LDPL_WARNING:
 624       vfinfo (stdout, format, args, TRUE);
 625       putchar ('\n');
 626       break;
 627     case LDPL_FATAL:
 628     case LDPL_ERROR:
 629     default:
 630       {
 631         char *newfmt = ACONCAT ((level == LDPL_FATAL ? "%P%F: " : "%P%X: ",
 632                                  format, "\n", (const char *) NULL));
 633         fflush (stdout);
 634         vfinfo (stderr, newfmt, args, TRUE);
 635         fflush (stderr);
 636       }
 637       break;
 638     }
 639
 640   va_end (args);
 641   return LDPS_OK;
 642 }
 643
 644 /* Helper to size leading part of tv array and set it up. */
 645 static size_t
 646 set_tv_header (struct ld_plugin_tv *tv)
 647 {
 648   size_t i;
 649
 650   /* Version info.  */
 651   static const unsigned int major = (unsigned)(BFD_VERSION / 100000000UL);
 652   static const unsigned int minor = (unsigned)(BFD_VERSION / 1000000UL) % 100;
 653
 654   if (!tv)
 655     return tv_header_size;
 656
 657   for (i = 0; i < tv_header_size; i++)
 658     {
 659       tv[i].tv_tag = tv_header_tags[i];
 660 #define TVU(x) tv[i].tv_u.tv_ ## x
 661       switch (tv[i].tv_tag)
 662         {
 663         case LDPT_MESSAGE:
 664           TVU(message) = message;
 665           break;
 666         case LDPT_API_VERSION:
 667           TVU(val) = LD_PLUGIN_API_VERSION;
 668           break;
 669         case LDPT_GNU_LD_VERSION:
 670           TVU(val) = major * 100 + minor;
 671           break;
 672         case LDPT_LINKER_OUTPUT:
 673           TVU(val) = (link_info.relocatable
 674                       ? LDPO_REL
 675                       : (link_info.shared ? LDPO_DYN : LDPO_EXEC));
 676           break;
 677         case LDPT_OUTPUT_NAME:
 678           TVU(string) = output_filename;
 679           break;
 680         case LDPT_REGISTER_CLAIM_FILE_HOOK:
 681           TVU(register_claim_file) = register_claim_file;
 682           break;
 683         case LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK:
 684           TVU(register_all_symbols_read) = register_all_symbols_read;
 685           break;
 686         case LDPT_REGISTER_CLEANUP_HOOK:
 687           TVU(register_cleanup) = register_cleanup;
 688           break;
 689         case LDPT_ADD_SYMBOLS:
 690           TVU(add_symbols) = add_symbols;
 691           break;
 692         case LDPT_GET_INPUT_FILE:
 693           TVU(get_input_file) = get_input_file;
 694           break;
 695         case LDPT_RELEASE_INPUT_FILE:
 696           TVU(release_input_file) = release_input_file;
 697           break;
 698         case LDPT_GET_SYMBOLS:
 699           TVU(get_symbols) = get_symbols;
 700           break;
 701         case LDPT_ADD_INPUT_FILE:
 702           TVU(add_input_file) = add_input_file;
 703           break;
 704         case LDPT_ADD_INPUT_LIBRARY:
 705           TVU(add_input_library) = add_input_library;
 706           break;
 707         case LDPT_SET_EXTRA_LIBRARY_PATH:
 708           TVU(set_extra_library_path) = set_extra_library_path;
 709           break;
 710         default:
 711           /* Added a new entry to the array without adding
 712              a new case to set up its value is a bug.  */
 713           FAIL ();
 714         }
 715 #undef TVU
 716     }
 717   return tv_header_size;
 718 }
 719
 720 /* Append the per-plugin args list and trailing LDPT_NULL to tv.  */
 721 static void
 722 set_tv_plugin_args (plugin_t *plugin, struct ld_plugin_tv *tv)
 723 {
 724   plugin_arg_t *arg = plugin->args;
 725   while (arg)
 726     {
 727       tv->tv_tag = LDPT_OPTION;
 728       tv->tv_u.tv_string = arg->arg;
 729       arg = arg->next;
 730       tv++;
 731     }
 732   tv->tv_tag = LDPT_NULL;
 733   tv->tv_u.tv_val = 0;
 734 }
 735
 736 /* Return true if any plugins are active this run.  Only valid
 737    after options have been processed.  */
 738 bfd_boolean
 739 plugin_active_plugins_p (void)
 740 {
 741   return plugins_list != NULL;
 742 }
 743
 744 /* Load up and initialise all plugins after argument parsing.  */
 745 int
 746 plugin_load_plugins (void)
 747 {
 748   struct ld_plugin_tv *my_tv;
 749   unsigned int max_args = 0;
 750   plugin_t *curplug = plugins_list;
 751
 752   /* If there are no plugins, we need do nothing this run.  */
 753   if (!curplug)
 754     return 0;
 755
 756   /* First pass over plugins to find max # args needed so that we
 757      can size and allocate the tv array.  */
 758   while (curplug)
 759     {
 760       if (curplug->n_args > max_args)
 761         max_args = curplug->n_args;
 762       curplug = curplug->next;
 763     }
 764
 765   /* Allocate tv array and initialise constant part.  */
 766   my_tv = xmalloc ((max_args + 1 + tv_header_size) * sizeof *my_tv);
 767   set_tv_header (my_tv);
 768
 769   /* Pass over plugins again, activating them.  */
 770   curplug = plugins_list;
 771   while (curplug)
 772     {
 773       enum ld_plugin_status rv;
 774       ld_plugin_onload onloadfn = dlsym (curplug->dlhandle, "onload");
 775       if (!onloadfn)
 776         onloadfn = dlsym (curplug->dlhandle, "_onload");
 777       if (!onloadfn)
 778         return set_plugin_error (curplug->name);
 779       set_tv_plugin_args (curplug, &my_tv[tv_header_size]);
 780       called_plugin = curplug;
 781       rv = (*onloadfn) (my_tv);
 782       called_plugin = NULL;
 783       if (rv != LDPS_OK)
 784         return set_plugin_error (curplug->name);
 785       curplug = curplug->next;
 786     }
 787
 788   /* Since plugin(s) inited ok, assume they're going to want symbol
 789      resolutions, which needs us to track which symbols are referenced
 790      by non-IR files using the linker's notice callback.  */
 791   orig_notice_all = link_info.notice_all;
 792   orig_callbacks = link_info.callbacks;
 793   plugin_callbacks = *orig_callbacks;
 794   plugin_callbacks.notice = &plugin_notice;
 795   link_info.notice_all = TRUE;
 796   link_info.callbacks = &plugin_callbacks;
 797
 798   return 0;
 799 }
 800
 801 /* Call 'claim file' hook for all plugins.  */
 802 static int
 803 plugin_call_claim_file (const struct ld_plugin_input_file *file, int *claimed)
 804 {
 805   plugin_t *curplug = plugins_list;
 806   *claimed = FALSE;
 807   if (no_more_claiming)
 808     return 0;
 809   while (curplug && !*claimed)
 810     {
 811       if (curplug->claim_file_handler)
 812         {
 813           enum ld_plugin_status rv;
 814           called_plugin = curplug;
 815           rv = (*curplug->claim_file_handler) (file, claimed);
 816           called_plugin = NULL;
 817           if (rv != LDPS_OK)
 818             set_plugin_error (curplug->name);
 819         }
 820       curplug = curplug->next;
 821     }
 822   return plugin_error_p () ? -1 : 0;
 823 }
 824
 825 void
 826 plugin_maybe_claim (struct ld_plugin_input_file *file,
 827                     lang_input_statement_type *entry)
 828 {
 829   int claimed = 0;
 830
 831   /* We create a dummy BFD, initially empty, to house whatever symbols
 832      the plugin may want to add.  */
 833   file->handle = plugin_get_ir_dummy_bfd (entry->the_bfd->filename,
 834                                           entry->the_bfd);
 835   if (plugin_call_claim_file (file, &claimed))
 836     einfo (_("%P%F: %s: plugin reported error claiming file\n"),
 837            plugin_error_plugin ());
 838   /* fd belongs to us, not the plugin; but we don't need it.  */
 839   close (file->fd);
 840   if (claimed)
 841     {
 842       /* Discard the real file's BFD and substitute the dummy one.  */
 843
 844       /* BFD archive handling caches elements so we can't call
 845          bfd_close for archives.  */
 846       if (entry->the_bfd->my_archive == NULL)
 847         bfd_close (entry->the_bfd);
 848       entry->the_bfd = file->handle;
 849       entry->claimed = TRUE;
 850       bfd_make_readable (entry->the_bfd);
 851     }
 852   else
 853     {
 854       /* If plugin didn't claim the file, we don't need the dummy bfd.
 855          Can't avoid speculatively creating it, alas.  */
 856       bfd_close_all_done (file->handle);
 857       entry->claimed = FALSE;
 858     }
 859 }
 860
 861 /* Call 'all symbols read' hook for all plugins.  */
 862 int
 863 plugin_call_all_symbols_read (void)
 864 {
 865   plugin_t *curplug = plugins_list;
 866
 867   /* Disable any further file-claiming.  */
 868   no_more_claiming = TRUE;
 869
 870   while (curplug)
 871     {
 872       if (curplug->all_symbols_read_handler)
 873         {
 874           enum ld_plugin_status rv;
 875           called_plugin = curplug;
 876           rv = (*curplug->all_symbols_read_handler) ();
 877           called_plugin = NULL;
 878           if (rv != LDPS_OK)
 879             set_plugin_error (curplug->name);
 880         }
 881       curplug = curplug->next;
 882     }
 883   return plugin_error_p () ? -1 : 0;
 884 }
 885
 886 /* Call 'cleanup' hook for all plugins at exit.  */
 887 void
 888 plugin_call_cleanup (void)
 889 {
 890   plugin_t *curplug = plugins_list;
 891   while (curplug)
 892     {
 893       if (curplug->cleanup_handler && !curplug->cleanup_done)
 894         {
 895           enum ld_plugin_status rv;
 896           curplug->cleanup_done = TRUE;
 897           called_plugin = curplug;
 898           rv = (*curplug->cleanup_handler) ();
 899           called_plugin = NULL;
 900           if (rv != LDPS_OK)
 901             set_plugin_error (curplug->name);
 902           dlclose (curplug->dlhandle);
 903         }
 904       curplug = curplug->next;
 905     }
 906   if (plugin_error_p ())
 907     info_msg (_("%P: %s: error in plugin cleanup (ignored)\n"),
 908               plugin_error_plugin ());
 909 }
 910
 911 /* To determine which symbols should be resolved LDPR_PREVAILING_DEF
 912    and which LDPR_PREVAILING_DEF_IRONLY, we notice all the symbols as
 913    the linker adds them to the linker hash table.  Mark those
 914    referenced from a non-IR file with non_ir_ref.  We have to
 915    notice_all symbols, because we won't necessarily know until later
 916    which ones will be contributed by IR files.  */
 917 static bfd_boolean
 918 plugin_notice (struct bfd_link_info *info,
 919                struct bfd_link_hash_entry *h,
 920                bfd *abfd,
 921                asection *section,
 922                bfd_vma value,
 923                flagword flags,
 924                const char *string)
 925 {
 926   if (h != NULL)
 927     {
 928       bfd *sym_bfd;
 929
 930       /* No further processing if this def/ref is from an IR dummy BFD.  */
 931       if (is_ir_dummy_bfd (abfd))
 932         return TRUE;
 933
 934       /* Making an indirect symbol counts as a reference unless this
 935          is a brand new symbol.  */
 936       if (bfd_is_ind_section (section)
 937           || (flags & BSF_INDIRECT) != 0)
 938         {
 939           if (h->type != bfd_link_hash_new)
 940             {
 941               struct bfd_link_hash_entry *inh;
 942
 943               h->non_ir_ref = TRUE;
 944               inh = bfd_wrapped_link_hash_lookup (abfd, info, string, FALSE,
 945                                                   FALSE, FALSE);
 946               if (inh != NULL)
 947                 inh->non_ir_ref = TRUE;
 948             }
 949         }
 950
 951       /* Nothing to do here for warning symbols.  */
 952       else if ((flags & BSF_WARNING) != 0)
 953         ;
 954
 955       /* Nothing to do here for constructor symbols.  */
 956       else if ((flags & BSF_CONSTRUCTOR) != 0)
 957         ;
 958
 959       /* If this is a ref, set non_ir_ref.  */
 960       else if (bfd_is_und_section (section))
 961         h->non_ir_ref = TRUE;
 962
 963       /* Otherwise, it must be a new def.  Ensure any symbol defined
 964          in an IR dummy BFD takes on a new value from a real BFD.
 965          Weak symbols are not normally overridden by a new weak
 966          definition, and strong symbols will normally cause multiple
 967          definition errors.  Avoid this by making the symbol appear
 968          to be undefined.  */
 969       else if (((h->type == bfd_link_hash_defweak
 970                  || h->type == bfd_link_hash_defined)
 971                 && is_ir_dummy_bfd (sym_bfd = h->u.def.section->owner))
 972                || (h->type == bfd_link_hash_common
 973                    && is_ir_dummy_bfd (sym_bfd = h->u.c.p->section->owner)))
 974         {
 975           h->type = bfd_link_hash_undefweak;
 976           h->u.undef.abfd = sym_bfd;
 977         }
 978     }
 979
 980   /* Continue with cref/nocrossref/trace-sym processing.  */
 981   if (h == NULL
 982       || orig_notice_all
 983       || (info->notice_hash != NULL
 984           && bfd_hash_lookup (info->notice_hash, h->root.string,
 985                               FALSE, FALSE) != NULL))
 986     return (*orig_callbacks->notice) (info, h,
 987                                       abfd, section, value, flags, string);
 988   return TRUE;
 989 }