gold/plugin.cc

   1 // plugin.cc -- plugin manager for gold      -*- C++ -*-
   2
   3 // Copyright 2008, 2009 Free Software Foundation, Inc.
   4 // Written by Cary Coutant <ccoutant@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 <cstdio>
  26 #include <cstdarg>
  27 #include <cstring>
  28 #include <string>
  29 #include <vector>
  30
  31 #ifdef ENABLE_PLUGINS
  32 #include <dlfcn.h>
  33 #endif
  34
  35 #include "parameters.h"
  36 #include "errors.h"
  37 #include "fileread.h"
  38 #include "layout.h"
  39 #include "options.h"
  40 #include "plugin.h"
  41 #include "target.h"
  42 #include "readsyms.h"
  43 #include "symtab.h"
  44 #include "elfcpp.h"
  45
  46 namespace gold
  47 {
  48
  49 #ifdef ENABLE_PLUGINS
  50
  51 // The linker's exported interfaces.
  52
  53 extern "C"
  54 {
  55
  56 static enum ld_plugin_status
  57 register_claim_file(ld_plugin_claim_file_handler handler);
  58
  59 static enum ld_plugin_status
  60 register_all_symbols_read(ld_plugin_all_symbols_read_handler handler);
  61
  62 static enum ld_plugin_status
  63 register_cleanup(ld_plugin_cleanup_handler handler);
  64
  65 static enum ld_plugin_status
  66 add_symbols(void *handle, int nsyms, const struct ld_plugin_symbol *syms);
  67
  68 static enum ld_plugin_status
  69 get_input_file(const void *handle, struct ld_plugin_input_file *file);
  70
  71 static enum ld_plugin_status
  72 release_input_file(const void *handle);
  73
  74 static enum ld_plugin_status
  75 get_symbols(const void *handle, int nsyms, struct ld_plugin_symbol *syms);
  76
  77 static enum ld_plugin_status
  78 add_input_file(char *pathname);
  79
  80 static enum ld_plugin_status
  81 add_input_library(char *pathname);
  82
  83 static enum ld_plugin_status
  84 message(int level, const char *format, ...);
  85
  86 };
  87
  88 #endif // ENABLE_PLUGINS
  89
  90 static Pluginobj* make_sized_plugin_object(Input_file* input_file,
  91                                            off_t offset, off_t filesize);
  92
  93 // Plugin methods.
  94
  95 // Load one plugin library.
  96
  97 void
  98 Plugin::load()
  99 {
 100 #ifdef ENABLE_PLUGINS
 101   // Load the plugin library.
 102   // FIXME: Look for the library in standard locations.
 103   this->handle_ = dlopen(this->filename_.c_str(), RTLD_NOW);
 104   if (this->handle_ == NULL)
 105     {
 106       gold_error(_("%s: could not load plugin library"),
 107                  this->filename_.c_str());
 108       return;
 109     }
 110
 111   // Find the plugin's onload entry point.
 112   void* ptr = dlsym(this->handle_, "onload");
 113   if (ptr == NULL)
 114     {
 115       gold_error(_("%s: could not find onload entry point"),
 116                  this->filename_.c_str());
 117       return;
 118     }
 119   ld_plugin_onload onload;
 120   gold_assert(sizeof(onload) == sizeof(ptr));
 121   memcpy(&onload, &ptr, sizeof(ptr));
 122
 123   // Get the linker's version number.
 124   const char* ver = get_version_string();
 125   int major = 0;
 126   int minor = 0;
 127   sscanf(ver, "%d.%d", &major, &minor);
 128
 129   // Allocate and populate a transfer vector.
 130   const int tv_fixed_size = 14;
 131   int tv_size = this->args_.size() + tv_fixed_size;
 132   ld_plugin_tv *tv = new ld_plugin_tv[tv_size];
 133
 134   // Put LDPT_MESSAGE at the front of the list so the plugin can use it
 135   // while processing subsequent entries.
 136   int i = 0;
 137   tv[i].tv_tag = LDPT_MESSAGE;
 138   tv[i].tv_u.tv_message = message;
 139
 140   ++i;
 141   tv[i].tv_tag = LDPT_API_VERSION;
 142   tv[i].tv_u.tv_val = LD_PLUGIN_API_VERSION;
 143
 144   ++i;
 145   tv[i].tv_tag = LDPT_GOLD_VERSION;
 146   tv[i].tv_u.tv_val = major * 100 + minor;
 147
 148   ++i;
 149   tv[i].tv_tag = LDPT_LINKER_OUTPUT;
 150   if (parameters->options().relocatable())
 151     tv[i].tv_u.tv_val = LDPO_REL;
 152   else if (parameters->options().shared())
 153     tv[i].tv_u.tv_val = LDPO_DYN;
 154   else
 155     tv[i].tv_u.tv_val = LDPO_EXEC;
 156
 157   for (unsigned int j = 0; j < this->args_.size(); ++j)
 158     {
 159       ++i;
 160       tv[i].tv_tag = LDPT_OPTION;
 161       tv[i].tv_u.tv_string = this->args_[j].c_str();
 162     }
 163
 164   ++i;
 165   tv[i].tv_tag = LDPT_REGISTER_CLAIM_FILE_HOOK;
 166   tv[i].tv_u.tv_register_claim_file = register_claim_file;
 167
 168   ++i;
 169   tv[i].tv_tag = LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK;
 170   tv[i].tv_u.tv_register_all_symbols_read = register_all_symbols_read;
 171
 172   ++i;
 173   tv[i].tv_tag = LDPT_REGISTER_CLEANUP_HOOK;
 174   tv[i].tv_u.tv_register_cleanup = register_cleanup;
 175
 176   ++i;
 177   tv[i].tv_tag = LDPT_ADD_SYMBOLS;
 178   tv[i].tv_u.tv_add_symbols = add_symbols;
 179
 180   ++i;
 181   tv[i].tv_tag = LDPT_GET_INPUT_FILE;
 182   tv[i].tv_u.tv_get_input_file = get_input_file;
 183
 184   ++i;
 185   tv[i].tv_tag = LDPT_RELEASE_INPUT_FILE;
 186   tv[i].tv_u.tv_release_input_file = release_input_file;
 187
 188   ++i;
 189   tv[i].tv_tag = LDPT_GET_SYMBOLS;
 190   tv[i].tv_u.tv_get_symbols = get_symbols;
 191
 192   ++i;
 193   tv[i].tv_tag = LDPT_ADD_INPUT_FILE;
 194   tv[i].tv_u.tv_add_input_file = add_input_file;
 195
 196   ++i;
 197   tv[i].tv_tag = LDPT_ADD_INPUT_LIBRARY;
 198   tv[i].tv_u.tv_add_input_library = add_input_library;
 199
 200   ++i;
 201   tv[i].tv_tag = LDPT_NULL;
 202   tv[i].tv_u.tv_val = 0;
 203
 204   gold_assert(i == tv_size - 1);
 205
 206   // Call the onload entry point.
 207   (*onload)(tv);
 208
 209   delete[] tv;
 210 #endif // ENABLE_PLUGINS
 211 }
 212
 213 // Call the plugin claim-file handler.
 214
 215 inline bool
 216 Plugin::claim_file(struct ld_plugin_input_file *plugin_input_file)
 217 {
 218   int claimed = 0;
 219
 220   if (this->claim_file_handler_ != NULL)
 221     {
 222       (*this->claim_file_handler_)(plugin_input_file, &claimed);
 223       if (claimed)
 224         return true;
 225     }
 226   return false;
 227 }
 228
 229 // Call the all-symbols-read handler.
 230
 231 inline void
 232 Plugin::all_symbols_read()
 233 {
 234   if (this->all_symbols_read_handler_ != NULL)
 235     (*this->all_symbols_read_handler_)();
 236 }
 237
 238 // Call the cleanup handler.
 239
 240 inline void
 241 Plugin::cleanup()
 242 {
 243   if (this->cleanup_handler_ != NULL && !this->cleanup_done_)
 244     {
 245       // Set this flag before calling to prevent a recursive plunge
 246       // in the event that a plugin's cleanup handler issues a
 247       // fatal error.
 248       this->cleanup_done_ = true;
 249       (*this->cleanup_handler_)();
 250     }
 251 }
 252
 253 // Plugin_manager methods.
 254
 255 Plugin_manager::~Plugin_manager()
 256 {
 257   for (Plugin_list::iterator p = this->plugins_.begin();
 258        p != this->plugins_.end();
 259        ++p)
 260     delete *p;
 261   this->plugins_.clear();
 262   for (Object_list::iterator obj = this->objects_.begin();
 263        obj != this->objects_.end();
 264        ++obj)
 265     delete *obj;
 266   this->objects_.clear();
 267 }
 268
 269 // Load all plugin libraries.
 270
 271 void
 272 Plugin_manager::load_plugins()
 273 {
 274   for (this->current_ = this->plugins_.begin();
 275        this->current_ != this->plugins_.end();
 276        ++this->current_)
 277     (*this->current_)->load();
 278 }
 279
 280 // Call the plugin claim-file handlers in turn to see if any claim the file.
 281
 282 Pluginobj*
 283 Plugin_manager::claim_file(Input_file* input_file, off_t offset,
 284                            off_t filesize)
 285 {
 286   if (this->in_replacement_phase_)
 287     return NULL;
 288
 289   unsigned int handle = this->objects_.size();
 290   this->input_file_ = input_file;
 291   this->plugin_input_file_.name = input_file->filename().c_str();
 292   this->plugin_input_file_.fd = input_file->file().descriptor();
 293   this->plugin_input_file_.offset = offset;
 294   this->plugin_input_file_.filesize = filesize;
 295   this->plugin_input_file_.handle = reinterpret_cast<void*>(handle);
 296
 297   for (this->current_ = this->plugins_.begin();
 298        this->current_ != this->plugins_.end();
 299        ++this->current_)
 300     {
 301       if ((*this->current_)->claim_file(&this->plugin_input_file_))
 302         {
 303           if (this->objects_.size() > handle)
 304             return this->objects_[handle];
 305
 306           // If the plugin claimed the file but did not call the
 307           // add_symbols callback, we need to create the Pluginobj now.
 308           Pluginobj* obj = this->make_plugin_object(handle);
 309           return obj;
 310         }
 311     }
 312
 313   return NULL;
 314 }
 315
 316 // Call the all-symbols-read handlers.
 317
 318 void
 319 Plugin_manager::all_symbols_read(Workqueue* workqueue, Task* task,
 320                                  Input_objects* input_objects,
 321                                  Symbol_table* symtab, Layout* layout,
 322                                  Dirsearch* dirpath, Mapfile* mapfile,
 323                                  Task_token** last_blocker)
 324 {
 325   this->in_replacement_phase_ = true;
 326   this->workqueue_ = workqueue;
 327   this->task_ = task;
 328   this->input_objects_ = input_objects;
 329   this->symtab_ = symtab;
 330   this->layout_ = layout;
 331   this->dirpath_ = dirpath;
 332   this->mapfile_ = mapfile;
 333   this->this_blocker_ = NULL;
 334
 335   for (this->current_ = this->plugins_.begin();
 336        this->current_ != this->plugins_.end();
 337        ++this->current_)
 338     (*this->current_)->all_symbols_read();
 339
 340   *last_blocker = this->this_blocker_;
 341 }
 342
 343 // Layout deferred objects.
 344
 345 void
 346 Plugin_manager::layout_deferred_objects()
 347 {
 348   Deferred_layout_list::iterator obj;
 349
 350   for (obj = this->deferred_layout_objects_.begin();
 351        obj != this->deferred_layout_objects_.end();
 352        ++obj)
 353     (*obj)->layout_deferred_sections(this->layout_);
 354 }
 355
 356 // Call the cleanup handlers.
 357
 358 void
 359 Plugin_manager::cleanup()
 360 {
 361   for (this->current_ = this->plugins_.begin();
 362        this->current_ != this->plugins_.end();
 363        ++this->current_)
 364     (*this->current_)->cleanup();
 365 }
 366
 367 // Make a new Pluginobj object.  This is called when the plugin calls
 368 // the add_symbols API.
 369
 370 Pluginobj*
 371 Plugin_manager::make_plugin_object(unsigned int handle)
 372 {
 373   // Make sure we aren't asked to make an object for the same handle twice.
 374   if (this->objects_.size() != handle)
 375     return NULL;
 376
 377   Pluginobj* obj = make_sized_plugin_object(this->input_file_,
 378                                             this->plugin_input_file_.offset,
 379                                             this->plugin_input_file_.filesize);
 380   this->objects_.push_back(obj);
 381   return obj;
 382 }
 383
 384 // Get the input file information with an open (possibly re-opened)
 385 // file descriptor.
 386
 387 ld_plugin_status
 388 Plugin_manager::get_input_file(unsigned int handle,
 389                                struct ld_plugin_input_file *file)
 390 {
 391   Pluginobj* obj = this->object(handle);
 392   if (obj == NULL)
 393     return LDPS_BAD_HANDLE;
 394
 395   obj->lock(this->task_);
 396   file->name = obj->filename().c_str();
 397   file->fd = obj->descriptor();
 398   file->offset = obj->offset();
 399   file->filesize = obj->filesize();
 400   file->handle = reinterpret_cast<void*>(handle);
 401   return LDPS_OK;
 402 }
 403
 404 // Release the input file.
 405
 406 ld_plugin_status
 407 Plugin_manager::release_input_file(unsigned int handle)
 408 {
 409   Pluginobj* obj = this->object(handle);
 410   if (obj == NULL)
 411     return LDPS_BAD_HANDLE;
 412
 413   obj->unlock(this->task_);
 414   return LDPS_OK;
 415 }
 416
 417 // Add a new input file.
 418
 419 ld_plugin_status
 420 Plugin_manager::add_input_file(char *pathname, bool is_lib)
 421 {
 422   Input_file_argument file(pathname,
 423                            (is_lib
 424                             ? Input_file_argument::INPUT_FILE_TYPE_LIBRARY
 425                             : Input_file_argument::INPUT_FILE_TYPE_FILE),
 426                            "", false, this->options_);
 427   Input_argument* input_argument = new Input_argument(file);
 428   Task_token* next_blocker = new Task_token(true);
 429   next_blocker->add_blocker();
 430   if (this->layout_->incremental_inputs())
 431     gold_error(_("input files added by plug-ins in --incremental mode not "
 432                  "supported yet"));
 433   this->workqueue_->queue_soon(new Read_symbols(this->input_objects_,
 434                                                 this->symtab_,
 435                                                 this->layout_,
 436                                                 this->dirpath_,
 437                                                 0,
 438                                                 this->mapfile_,
 439                                                 input_argument,
 440                                                 NULL,
 441                                                 this->this_blocker_,
 442                                                 next_blocker));
 443   this->this_blocker_ = next_blocker;
 444   return LDPS_OK;
 445 }
 446
 447 // Class Pluginobj.
 448
 449 Pluginobj::Pluginobj(const std::string& name, Input_file* input_file,
 450                      off_t offset, off_t filesize)
 451   : Object(name, input_file, false, offset),
 452     nsyms_(0), syms_(NULL), symbols_(), filesize_(filesize), comdat_map_()
 453 {
 454 }
 455
 456 // Return TRUE if a defined symbol might be reachable from outside the
 457 // universe of claimed objects.
 458
 459 static inline bool
 460 is_visible_from_outside(Symbol* lsym)
 461 {
 462   if (lsym->in_real_elf())
 463     return true;
 464   if (parameters->options().relocatable())
 465     return true;
 466   if (parameters->options().export_dynamic() || parameters->options().shared())
 467     return lsym->is_externally_visible();
 468   return false;
 469 }
 470
 471 // Get symbol resolution info.
 472
 473 ld_plugin_status
 474 Pluginobj::get_symbol_resolution_info(int nsyms, ld_plugin_symbol* syms) const
 475 {
 476   if (nsyms > this->nsyms_)
 477     return LDPS_NO_SYMS;
 478   for (int i = 0; i < nsyms; i++)
 479     {
 480       ld_plugin_symbol* isym = &syms[i];
 481       Symbol* lsym = this->symbols_[i];
 482       ld_plugin_symbol_resolution res = LDPR_UNKNOWN;
 483
 484       if (lsym->is_undefined())
 485         // The symbol remains undefined.
 486         res = LDPR_UNDEF;
 487       else if (isym->def == LDPK_UNDEF
 488                || isym->def == LDPK_WEAKUNDEF
 489                || isym->def == LDPK_COMMON)
 490         {
 491           // The original symbol was undefined or common.
 492           if (lsym->source() != Symbol::FROM_OBJECT)
 493             res = LDPR_RESOLVED_EXEC;
 494           else if (lsym->object()->pluginobj() != NULL)
 495             res = LDPR_RESOLVED_IR;
 496           else if (lsym->object()->is_dynamic())
 497             res = LDPR_RESOLVED_DYN;
 498           else
 499             res = LDPR_RESOLVED_EXEC;
 500         }
 501       else
 502         {
 503           // The original symbol was a definition.
 504           if (lsym->source() != Symbol::FROM_OBJECT)
 505             res = LDPR_PREEMPTED_REG;
 506           else if (lsym->object() == static_cast<const Object*>(this))
 507             res = (is_visible_from_outside(lsym)
 508                    ? LDPR_PREVAILING_DEF
 509                    : LDPR_PREVAILING_DEF_IRONLY);
 510           else
 511             res = (lsym->object()->pluginobj() != NULL
 512                    ? LDPR_PREEMPTED_IR
 513                    : LDPR_PREEMPTED_REG);
 514         }
 515       isym->resolution = res;
 516     }
 517   return LDPS_OK;
 518 }
 519
 520 // Return TRUE if the comdat group with key COMDAT_KEY from this object
 521 // should be kept.
 522
 523 bool
 524 Pluginobj::include_comdat_group(std::string comdat_key, Layout* layout)
 525 {
 526   std::pair<Comdat_map::iterator, bool> ins =
 527     this->comdat_map_.insert(std::make_pair(comdat_key, false));
 528
 529   // If this is the first time we've seen this comdat key, ask the
 530   // layout object whether it should be included.
 531   if (ins.second)
 532     ins.first->second = layout->find_or_add_kept_section(comdat_key,
 533                                                          NULL, 0, true,
 534                                                          true, NULL);
 535
 536   return ins.first->second;
 537 }
 538
 539 // Class Sized_pluginobj.
 540
 541 template<int size, bool big_endian>
 542 Sized_pluginobj<size, big_endian>::Sized_pluginobj(
 543     const std::string& name,
 544     Input_file* input_file,
 545     off_t offset,
 546     off_t filesize)
 547   : Pluginobj(name, input_file, offset, filesize)
 548 {
 549 }
 550
 551 // Read the symbols.  Not used for plugin objects.
 552
 553 template<int size, bool big_endian>
 554 void
 555 Sized_pluginobj<size, big_endian>::do_read_symbols(Read_symbols_data*)
 556 {
 557   gold_unreachable();
 558 }
 559
 560 // Lay out the input sections.  Not used for plugin objects.
 561
 562 template<int size, bool big_endian>
 563 void
 564 Sized_pluginobj<size, big_endian>::do_layout(Symbol_table*, Layout*,
 565                                              Read_symbols_data*)
 566 {
 567   gold_unreachable();
 568 }
 569
 570 // Add the symbols to the symbol table.
 571
 572 template<int size, bool big_endian>
 573 void
 574 Sized_pluginobj<size, big_endian>::do_add_symbols(Symbol_table* symtab,
 575                                                   Read_symbols_data*,
 576                                                   Layout* layout)
 577 {
 578   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
 579   unsigned char symbuf[sym_size];
 580   elfcpp::Sym<size, big_endian> sym(symbuf);
 581   elfcpp::Sym_write<size, big_endian> osym(symbuf);
 582
 583   typedef typename elfcpp::Elf_types<size>::Elf_WXword Elf_size_type;
 584
 585   this->symbols_.resize(this->nsyms_);
 586
 587   for (int i = 0; i < this->nsyms_; ++i)
 588     {
 589       const struct ld_plugin_symbol *isym = &this->syms_[i];
 590       const char* name = isym->name;
 591       const char* ver = isym->version;
 592       elfcpp::Elf_Half shndx;
 593       elfcpp::STB bind;
 594       elfcpp::STV vis;
 595
 596       if (name != NULL && name[0] == '\0')
 597         name = NULL;
 598       if (ver != NULL && ver[0] == '\0')
 599         ver = NULL;
 600
 601       switch (isym->def)
 602         {
 603         case LDPK_WEAKDEF:
 604         case LDPK_WEAKUNDEF:
 605           bind = elfcpp::STB_WEAK;
 606           break;
 607         case LDPK_DEF:
 608         case LDPK_UNDEF:
 609         case LDPK_COMMON:
 610         default:
 611           bind = elfcpp::STB_GLOBAL;
 612           break;
 613         }
 614
 615       switch (isym->def)
 616         {
 617         case LDPK_DEF:
 618         case LDPK_WEAKDEF:
 619           shndx = elfcpp::SHN_ABS;
 620           break;
 621         case LDPK_COMMON:
 622           shndx = elfcpp::SHN_COMMON;
 623           break;
 624         case LDPK_UNDEF:
 625         case LDPK_WEAKUNDEF:
 626         default:
 627           shndx = elfcpp::SHN_UNDEF;
 628           break;
 629         }
 630
 631       switch (isym->visibility)
 632         {
 633         case LDPV_PROTECTED:
 634           vis = elfcpp::STV_DEFAULT;
 635           break;
 636         case LDPV_INTERNAL:
 637           vis = elfcpp::STV_DEFAULT;
 638           break;
 639         case LDPV_HIDDEN:
 640           vis = elfcpp::STV_DEFAULT;
 641           break;
 642         case LDPV_DEFAULT:
 643         default:
 644           vis = elfcpp::STV_DEFAULT;
 645           break;
 646         }
 647
 648       if (isym->comdat_key != NULL
 649           && isym->comdat_key[0] != '\0'
 650           && !this->include_comdat_group(isym->comdat_key, layout))
 651         shndx = elfcpp::SHN_UNDEF;
 652
 653       osym.put_st_name(0);
 654       osym.put_st_value(0);
 655       osym.put_st_size(static_cast<Elf_size_type>(isym->size));
 656       osym.put_st_info(bind, elfcpp::STT_NOTYPE);
 657       osym.put_st_other(vis, 0);
 658       osym.put_st_shndx(shndx);
 659
 660       this->symbols_[i] =
 661         symtab->add_from_pluginobj<size, big_endian>(this, name, ver, &sym);
 662     }
 663 }
 664
 665 // Get the size of a section.  Not used for plugin objects.
 666
 667 template<int size, bool big_endian>
 668 uint64_t
 669 Sized_pluginobj<size, big_endian>::do_section_size(unsigned int)
 670 {
 671   gold_unreachable();
 672   return 0;
 673 }
 674
 675 // Get the name of a section.  Not used for plugin objects.
 676
 677 template<int size, bool big_endian>
 678 std::string
 679 Sized_pluginobj<size, big_endian>::do_section_name(unsigned int)
 680 {
 681   gold_unreachable();
 682   return std::string();
 683 }
 684
 685 // Return a view of the contents of a section.  Not used for plugin objects.
 686
 687 template<int size, bool big_endian>
 688 Object::Location
 689 Sized_pluginobj<size, big_endian>::do_section_contents(unsigned int)
 690 {
 691   Location loc(0, 0);
 692
 693   gold_unreachable();
 694   return loc;
 695 }
 696
 697 // Return section flags.  Not used for plugin objects.
 698
 699 template<int size, bool big_endian>
 700 uint64_t
 701 Sized_pluginobj<size, big_endian>::do_section_flags(unsigned int)
 702 {
 703   gold_unreachable();
 704   return 0;
 705 }
 706
 707 // Return section entsize.  Not used for plugin objects.
 708
 709 template<int size, bool big_endian>
 710 uint64_t
 711 Sized_pluginobj<size, big_endian>::do_section_entsize(unsigned int)
 712 {
 713   gold_unreachable();
 714   return 0;
 715 }
 716
 717 // Return section address.  Not used for plugin objects.
 718
 719 template<int size, bool big_endian>
 720 uint64_t
 721 Sized_pluginobj<size, big_endian>::do_section_address(unsigned int)
 722 {
 723   gold_unreachable();
 724   return 0;
 725 }
 726
 727 // Return section type.  Not used for plugin objects.
 728
 729 template<int size, bool big_endian>
 730 unsigned int
 731 Sized_pluginobj<size, big_endian>::do_section_type(unsigned int)
 732 {
 733   gold_unreachable();
 734   return 0;
 735 }
 736
 737 // Return the section link field.  Not used for plugin objects.
 738
 739 template<int size, bool big_endian>
 740 unsigned int
 741 Sized_pluginobj<size, big_endian>::do_section_link(unsigned int)
 742 {
 743   gold_unreachable();
 744   return 0;
 745 }
 746
 747 // Return the section link field.  Not used for plugin objects.
 748
 749 template<int size, bool big_endian>
 750 unsigned int
 751 Sized_pluginobj<size, big_endian>::do_section_info(unsigned int)
 752 {
 753   gold_unreachable();
 754   return 0;
 755 }
 756
 757 // Return the section alignment.  Not used for plugin objects.
 758
 759 template<int size, bool big_endian>
 760 uint64_t
 761 Sized_pluginobj<size, big_endian>::do_section_addralign(unsigned int)
 762 {
 763   gold_unreachable();
 764   return 0;
 765 }
 766
 767 // Return the Xindex structure to use.  Not used for plugin objects.
 768
 769 template<int size, bool big_endian>
 770 Xindex*
 771 Sized_pluginobj<size, big_endian>::do_initialize_xindex()
 772 {
 773   gold_unreachable();
 774   return NULL;
 775 }
 776
 777 // Get symbol counts.  Not used for plugin objects.
 778
 779 template<int size, bool big_endian>
 780 void
 781 Sized_pluginobj<size, big_endian>::do_get_global_symbol_counts(const Symbol_table*,
 782                                                    size_t*, size_t*) const
 783 {
 784   gold_unreachable();
 785 }
 786
 787 // Class Plugin_finish.  This task runs after all replacement files have
 788 // been added.  It calls each plugin's cleanup handler.
 789
 790 class Plugin_finish : public Task
 791 {
 792  public:
 793   Plugin_finish(Task_token* this_blocker, Task_token* next_blocker)
 794     : this_blocker_(this_blocker), next_blocker_(next_blocker)
 795   { }
 796
 797   ~Plugin_finish()
 798   {
 799     if (this->this_blocker_ != NULL)
 800       delete this->this_blocker_;
 801   }
 802
 803   Task_token*
 804   is_runnable()
 805   {
 806     if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 807       return this->this_blocker_;
 808     return NULL;
 809   }
 810
 811   void
 812   locks(Task_locker* tl)
 813   { tl->add(this, this->next_blocker_); }
 814
 815   void
 816   run(Workqueue*)
 817   {
 818     Plugin_manager* plugins = parameters->options().plugins();
 819     gold_assert(plugins != NULL);
 820     plugins->cleanup();
 821   }
 822
 823   std::string
 824   get_name() const
 825   { return "Plugin_finish"; }
 826
 827  private:
 828   Task_token* this_blocker_;
 829   Task_token* next_blocker_;
 830 };
 831
 832 // Class Plugin_hook.
 833
 834 Plugin_hook::~Plugin_hook()
 835 {
 836 }
 837
 838 // Return whether a Plugin_hook task is runnable.
 839
 840 Task_token*
 841 Plugin_hook::is_runnable()
 842 {
 843   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 844     return this->this_blocker_;
 845   return NULL;
 846 }
 847
 848 // Return a Task_locker for a Plugin_hook task.  We don't need any
 849 // locks here.
 850
 851 void
 852 Plugin_hook::locks(Task_locker*)
 853 {
 854 }
 855
 856 // Run the "all symbols read" plugin hook.
 857
 858 void
 859 Plugin_hook::run(Workqueue* workqueue)
 860 {
 861   gold_assert(this->options_.has_plugins());
 862   this->options_.plugins()->all_symbols_read(workqueue,
 863                                              this,
 864                                              this->input_objects_,
 865                                              this->symtab_,
 866                                              this->layout_,
 867                                              this->dirpath_,
 868                                              this->mapfile_,
 869                                              &this->this_blocker_);
 870   workqueue->queue_soon(new Plugin_finish(this->this_blocker_,
 871                                           this->next_blocker_));
 872 }
 873
 874 // The C interface routines called by the plugins.
 875
 876 #ifdef ENABLE_PLUGINS
 877
 878 // Register a claim-file handler.
 879
 880 static enum ld_plugin_status
 881 register_claim_file(ld_plugin_claim_file_handler handler)
 882 {
 883   gold_assert(parameters->options().has_plugins());
 884   parameters->options().plugins()->set_claim_file_handler(handler);
 885   return LDPS_OK;
 886 }
 887
 888 // Register an all-symbols-read handler.
 889
 890 static enum ld_plugin_status
 891 register_all_symbols_read(ld_plugin_all_symbols_read_handler handler)
 892 {
 893   gold_assert(parameters->options().has_plugins());
 894   parameters->options().plugins()->set_all_symbols_read_handler(handler);
 895   return LDPS_OK;
 896 }
 897
 898 // Register a cleanup handler.
 899
 900 static enum ld_plugin_status
 901 register_cleanup(ld_plugin_cleanup_handler handler)
 902 {
 903   gold_assert(parameters->options().has_plugins());
 904   parameters->options().plugins()->set_cleanup_handler(handler);
 905   return LDPS_OK;
 906 }
 907
 908 // Add symbols from a plugin-claimed input file.
 909
 910 static enum ld_plugin_status
 911 add_symbols(void* handle, int nsyms, const ld_plugin_symbol *syms)
 912 {
 913   gold_assert(parameters->options().has_plugins());
 914   Pluginobj* obj = parameters->options().plugins()->make_plugin_object(
 915       static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
 916   if (obj == NULL)
 917     return LDPS_ERR;
 918   obj->store_incoming_symbols(nsyms, syms);
 919   return LDPS_OK;
 920 }
 921
 922 // Get the input file information with an open (possibly re-opened)
 923 // file descriptor.
 924
 925 static enum ld_plugin_status
 926 get_input_file(const void *handle, struct ld_plugin_input_file *file)
 927 {
 928   gold_assert(parameters->options().has_plugins());
 929   unsigned int obj_index =
 930       static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle));
 931   return parameters->options().plugins()->get_input_file(obj_index, file);
 932 }
 933
 934 // Release the input file.
 935
 936 static enum ld_plugin_status
 937 release_input_file(const void *handle)
 938 {
 939   gold_assert(parameters->options().has_plugins());
 940   unsigned int obj_index =
 941       static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle));
 942   return parameters->options().plugins()->release_input_file(obj_index);
 943 }
 944
 945 // Get the symbol resolution info for a plugin-claimed input file.
 946
 947 static enum ld_plugin_status
 948 get_symbols(const void * handle, int nsyms, ld_plugin_symbol* syms)
 949 {
 950   gold_assert(parameters->options().has_plugins());
 951   Pluginobj* obj = parameters->options().plugins()->object(
 952       static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
 953   if (obj == NULL)
 954     return LDPS_ERR;
 955   return obj->get_symbol_resolution_info(nsyms, syms);
 956 }
 957
 958 // Add a new (real) input file generated by a plugin.
 959
 960 static enum ld_plugin_status
 961 add_input_file(char *pathname)
 962 {
 963   gold_assert(parameters->options().has_plugins());
 964   return parameters->options().plugins()->add_input_file(pathname, false);
 965 }
 966
 967 // Add a new (real) library required by a plugin.
 968
 969 static enum ld_plugin_status
 970 add_input_library(char *pathname)
 971 {
 972   gold_assert(parameters->options().has_plugins());
 973   return parameters->options().plugins()->add_input_file(pathname, true);
 974 }
 975
 976 // Issue a diagnostic message from a plugin.
 977
 978 static enum ld_plugin_status
 979 message(int level, const char * format, ...)
 980 {
 981   va_list args;
 982   va_start(args, format);
 983
 984   switch (level)
 985     {
 986     case LDPL_INFO:
 987       parameters->errors()->info(format, args);
 988       break;
 989     case LDPL_WARNING:
 990       parameters->errors()->warning(format, args);
 991       break;
 992     case LDPL_ERROR:
 993     default:
 994       parameters->errors()->error(format, args);
 995       break;
 996     case LDPL_FATAL:
 997       parameters->errors()->fatal(format, args);
 998       break;
 999     }
1000
1001   va_end(args);
1002   return LDPS_OK;
1003 }
1004
1005 #endif // ENABLE_PLUGINS
1006
1007 // Allocate a Pluginobj object of the appropriate size and endianness.
1008
1009 static Pluginobj*
1010 make_sized_plugin_object(Input_file* input_file, off_t offset, off_t filesize)
1011 {
1012   Pluginobj* obj = NULL;
1013
1014   parameters_force_valid_target();
1015   const Target& target(parameters->target());
1016
1017   if (target.get_size() == 32)
1018     {
1019       if (target.is_big_endian())
1020 #ifdef HAVE_TARGET_32_BIG
1021         obj = new Sized_pluginobj<32, true>(input_file->filename(),
1022                                             input_file, offset, filesize);
1023 #else
1024         gold_error(_("%s: not configured to support "
1025                      "32-bit big-endian object"),
1026                    input_file->filename().c_str());
1027 #endif
1028       else
1029 #ifdef HAVE_TARGET_32_LITTLE
1030         obj = new Sized_pluginobj<32, false>(input_file->filename(),
1031                                              input_file, offset, filesize);
1032 #else
1033         gold_error(_("%s: not configured to support "
1034                      "32-bit little-endian object"),
1035                    input_file->filename().c_str());
1036 #endif
1037     }
1038   else if (target.get_size() == 64)
1039     {
1040       if (target.is_big_endian())
1041 #ifdef HAVE_TARGET_64_BIG
1042         obj = new Sized_pluginobj<64, true>(input_file->filename(),
1043                                             input_file, offset, filesize);
1044 #else
1045         gold_error(_("%s: not configured to support "
1046                      "64-bit big-endian object"),
1047                    input_file->filename().c_str());
1048 #endif
1049       else
1050 #ifdef HAVE_TARGET_64_LITTLE
1051         obj = new Sized_pluginobj<64, false>(input_file->filename(),
1052                                              input_file, offset, filesize);
1053 #else
1054         gold_error(_("%s: not configured to support "
1055                      "64-bit little-endian object"),
1056                    input_file->filename().c_str());
1057 #endif
1058     }
1059
1060   gold_assert(obj != NULL);
1061   return obj;
1062 }
1063
1064 } // End namespace gold.