gold/plugin.cc

   1 // plugin.cc -- plugin manager for gold      -*- C++ -*-
   2
   3 // Copyright 2008, 2009, 2010 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(const char *pathname);
  79
  80 static enum ld_plugin_status
  81 add_input_library(const 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 = 15;
 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   ++i;
 158   tv[i].tv_tag = LDPT_OUTPUT_NAME;
 159   tv[i].tv_u.tv_string = parameters->options().output();
 160
 161   for (unsigned int j = 0; j < this->args_.size(); ++j)
 162     {
 163       ++i;
 164       tv[i].tv_tag = LDPT_OPTION;
 165       tv[i].tv_u.tv_string = this->args_[j].c_str();
 166     }
 167
 168   ++i;
 169   tv[i].tv_tag = LDPT_REGISTER_CLAIM_FILE_HOOK;
 170   tv[i].tv_u.tv_register_claim_file = register_claim_file;
 171
 172   ++i;
 173   tv[i].tv_tag = LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK;
 174   tv[i].tv_u.tv_register_all_symbols_read = register_all_symbols_read;
 175
 176   ++i;
 177   tv[i].tv_tag = LDPT_REGISTER_CLEANUP_HOOK;
 178   tv[i].tv_u.tv_register_cleanup = register_cleanup;
 179
 180   ++i;
 181   tv[i].tv_tag = LDPT_ADD_SYMBOLS;
 182   tv[i].tv_u.tv_add_symbols = add_symbols;
 183
 184   ++i;
 185   tv[i].tv_tag = LDPT_GET_INPUT_FILE;
 186   tv[i].tv_u.tv_get_input_file = get_input_file;
 187
 188   ++i;
 189   tv[i].tv_tag = LDPT_RELEASE_INPUT_FILE;
 190   tv[i].tv_u.tv_release_input_file = release_input_file;
 191
 192   ++i;
 193   tv[i].tv_tag = LDPT_GET_SYMBOLS;
 194   tv[i].tv_u.tv_get_symbols = get_symbols;
 195
 196   ++i;
 197   tv[i].tv_tag = LDPT_ADD_INPUT_FILE;
 198   tv[i].tv_u.tv_add_input_file = add_input_file;
 199
 200   ++i;
 201   tv[i].tv_tag = LDPT_ADD_INPUT_LIBRARY;
 202   tv[i].tv_u.tv_add_input_library = add_input_library;
 203
 204   ++i;
 205   tv[i].tv_tag = LDPT_NULL;
 206   tv[i].tv_u.tv_val = 0;
 207
 208   gold_assert(i == tv_size - 1);
 209
 210   // Call the onload entry point.
 211   (*onload)(tv);
 212
 213   delete[] tv;
 214 #endif // ENABLE_PLUGINS
 215 }
 216
 217 // Call the plugin claim-file handler.
 218
 219 inline bool
 220 Plugin::claim_file(struct ld_plugin_input_file *plugin_input_file)
 221 {
 222   int claimed = 0;
 223
 224   if (this->claim_file_handler_ != NULL)
 225     {
 226       (*this->claim_file_handler_)(plugin_input_file, &claimed);
 227       if (claimed)
 228         return true;
 229     }
 230   return false;
 231 }
 232
 233 // Call the all-symbols-read handler.
 234
 235 inline void
 236 Plugin::all_symbols_read()
 237 {
 238   if (this->all_symbols_read_handler_ != NULL)
 239     (*this->all_symbols_read_handler_)();
 240 }
 241
 242 // Call the cleanup handler.
 243
 244 inline void
 245 Plugin::cleanup()
 246 {
 247   if (this->cleanup_handler_ != NULL && !this->cleanup_done_)
 248     {
 249       // Set this flag before calling to prevent a recursive plunge
 250       // in the event that a plugin's cleanup handler issues a
 251       // fatal error.
 252       this->cleanup_done_ = true;
 253       (*this->cleanup_handler_)();
 254     }
 255 }
 256
 257 // Plugin_manager methods.
 258
 259 Plugin_manager::~Plugin_manager()
 260 {
 261   for (Plugin_list::iterator p = this->plugins_.begin();
 262        p != this->plugins_.end();
 263        ++p)
 264     delete *p;
 265   this->plugins_.clear();
 266   for (Object_list::iterator obj = this->objects_.begin();
 267        obj != this->objects_.end();
 268        ++obj)
 269     delete *obj;
 270   this->objects_.clear();
 271 }
 272
 273 // Load all plugin libraries.
 274
 275 void
 276 Plugin_manager::load_plugins()
 277 {
 278   for (this->current_ = this->plugins_.begin();
 279        this->current_ != this->plugins_.end();
 280        ++this->current_)
 281     (*this->current_)->load();
 282 }
 283
 284 // Call the plugin claim-file handlers in turn to see if any claim the file.
 285
 286 Pluginobj*
 287 Plugin_manager::claim_file(Input_file* input_file, off_t offset,
 288                            off_t filesize)
 289 {
 290   if (this->in_replacement_phase_)
 291     return NULL;
 292
 293   unsigned int handle = this->objects_.size();
 294   this->input_file_ = input_file;
 295   this->plugin_input_file_.name = input_file->filename().c_str();
 296   this->plugin_input_file_.fd = input_file->file().descriptor();
 297   this->plugin_input_file_.offset = offset;
 298   this->plugin_input_file_.filesize = filesize;
 299   this->plugin_input_file_.handle = reinterpret_cast<void*>(handle);
 300
 301   for (this->current_ = this->plugins_.begin();
 302        this->current_ != this->plugins_.end();
 303        ++this->current_)
 304     {
 305       if ((*this->current_)->claim_file(&this->plugin_input_file_))
 306         {
 307           if (this->objects_.size() > handle)
 308             return this->objects_[handle];
 309
 310           // If the plugin claimed the file but did not call the
 311           // add_symbols callback, we need to create the Pluginobj now.
 312           Pluginobj* obj = this->make_plugin_object(handle);
 313           return obj;
 314         }
 315     }
 316
 317   return NULL;
 318 }
 319
 320 // Call the all-symbols-read handlers.
 321
 322 void
 323 Plugin_manager::all_symbols_read(Workqueue* workqueue, Task* task,
 324                                  Input_objects* input_objects,
 325                                  Symbol_table* symtab, Layout* layout,
 326                                  Dirsearch* dirpath, Mapfile* mapfile,
 327                                  Task_token** last_blocker)
 328 {
 329   this->in_replacement_phase_ = true;
 330   this->workqueue_ = workqueue;
 331   this->task_ = task;
 332   this->input_objects_ = input_objects;
 333   this->symtab_ = symtab;
 334   this->layout_ = layout;
 335   this->dirpath_ = dirpath;
 336   this->mapfile_ = mapfile;
 337   this->this_blocker_ = NULL;
 338
 339   for (this->current_ = this->plugins_.begin();
 340        this->current_ != this->plugins_.end();
 341        ++this->current_)
 342     (*this->current_)->all_symbols_read();
 343
 344   *last_blocker = this->this_blocker_;
 345 }
 346
 347 // Layout deferred objects.
 348
 349 void
 350 Plugin_manager::layout_deferred_objects()
 351 {
 352   Deferred_layout_list::iterator obj;
 353
 354   for (obj = this->deferred_layout_objects_.begin();
 355        obj != this->deferred_layout_objects_.end();
 356        ++obj)
 357     (*obj)->layout_deferred_sections(this->layout_);
 358 }
 359
 360 // Call the cleanup handlers.
 361
 362 void
 363 Plugin_manager::cleanup()
 364 {
 365   for (this->current_ = this->plugins_.begin();
 366        this->current_ != this->plugins_.end();
 367        ++this->current_)
 368     (*this->current_)->cleanup();
 369 }
 370
 371 // Make a new Pluginobj object.  This is called when the plugin calls
 372 // the add_symbols API.
 373
 374 Pluginobj*
 375 Plugin_manager::make_plugin_object(unsigned int handle)
 376 {
 377   // Make sure we aren't asked to make an object for the same handle twice.
 378   if (this->objects_.size() != handle)
 379     return NULL;
 380
 381   Pluginobj* obj = make_sized_plugin_object(this->input_file_,
 382                                             this->plugin_input_file_.offset,
 383                                             this->plugin_input_file_.filesize);
 384   this->objects_.push_back(obj);
 385   return obj;
 386 }
 387
 388 // Get the input file information with an open (possibly re-opened)
 389 // file descriptor.
 390
 391 ld_plugin_status
 392 Plugin_manager::get_input_file(unsigned int handle,
 393                                struct ld_plugin_input_file *file)
 394 {
 395   Pluginobj* obj = this->object(handle);
 396   if (obj == NULL)
 397     return LDPS_BAD_HANDLE;
 398
 399   obj->lock(this->task_);
 400   file->name = obj->filename().c_str();
 401   file->fd = obj->descriptor();
 402   file->offset = obj->offset();
 403   file->filesize = obj->filesize();
 404   file->handle = reinterpret_cast<void*>(handle);
 405   return LDPS_OK;
 406 }
 407
 408 // Release the input file.
 409
 410 ld_plugin_status
 411 Plugin_manager::release_input_file(unsigned int handle)
 412 {
 413   Pluginobj* obj = this->object(handle);
 414   if (obj == NULL)
 415     return LDPS_BAD_HANDLE;
 416
 417   obj->unlock(this->task_);
 418   return LDPS_OK;
 419 }
 420
 421 // Add a new input file.
 422
 423 ld_plugin_status
 424 Plugin_manager::add_input_file(const char *pathname, bool is_lib)
 425 {
 426   Input_file_argument file(pathname,
 427                            (is_lib
 428                             ? Input_file_argument::INPUT_FILE_TYPE_LIBRARY
 429                             : Input_file_argument::INPUT_FILE_TYPE_FILE),
 430                            "", false, this->options_);
 431   Input_argument* input_argument = new Input_argument(file);
 432   Task_token* next_blocker = new Task_token(true);
 433   next_blocker->add_blocker();
 434   if (this->layout_->incremental_inputs())
 435     gold_error(_("input files added by plug-ins in --incremental mode not "
 436                  "supported yet"));
 437   this->workqueue_->queue_soon(new Read_symbols(this->input_objects_,
 438                                                 this->symtab_,
 439                                                 this->layout_,
 440                                                 this->dirpath_,
 441                                                 0,
 442                                                 this->mapfile_,
 443                                                 input_argument,
 444                                                 NULL,
 445                                                 NULL,
 446                                                 this->this_blocker_,
 447                                                 next_blocker));
 448   this->this_blocker_ = next_blocker;
 449   return LDPS_OK;
 450 }
 451
 452 // Class Pluginobj.
 453
 454 Pluginobj::Pluginobj(const std::string& name, Input_file* input_file,
 455                      off_t offset, off_t filesize)
 456   : Object(name, input_file, false, offset),
 457     nsyms_(0), syms_(NULL), symbols_(), filesize_(filesize), comdat_map_()
 458 {
 459 }
 460
 461 // Return TRUE if a defined symbol might be reachable from outside the
 462 // universe of claimed objects.
 463
 464 static inline bool
 465 is_visible_from_outside(Symbol* lsym)
 466 {
 467   if (lsym->in_real_elf())
 468     return true;
 469   if (parameters->options().relocatable())
 470     return true;
 471   if (parameters->options().export_dynamic() || parameters->options().shared())
 472     return lsym->is_externally_visible();
 473   return false;
 474 }
 475
 476 // Get symbol resolution info.
 477
 478 ld_plugin_status
 479 Pluginobj::get_symbol_resolution_info(int nsyms, ld_plugin_symbol* syms) const
 480 {
 481   if (nsyms > this->nsyms_)
 482     return LDPS_NO_SYMS;
 483
 484   if (static_cast<size_t>(nsyms) > this->symbols_.size())
 485     {
 486       // We never decided to include this object. We mark all symbols as
 487       // preempted.
 488       gold_assert (this->symbols_.size() == 0);
 489       for (int i = 0; i < nsyms; i++)
 490         syms[i].resolution = LDPR_PREEMPTED_REG;
 491       return LDPS_OK;
 492     }
 493
 494   for (int i = 0; i < nsyms; i++)
 495     {
 496       ld_plugin_symbol* isym = &syms[i];
 497       Symbol* lsym = this->symbols_[i];
 498       ld_plugin_symbol_resolution res = LDPR_UNKNOWN;
 499
 500       if (lsym->is_undefined())
 501         // The symbol remains undefined.
 502         res = LDPR_UNDEF;
 503       else if (isym->def == LDPK_UNDEF
 504                || isym->def == LDPK_WEAKUNDEF
 505                || isym->def == LDPK_COMMON)
 506         {
 507           // The original symbol was undefined or common.
 508           if (lsym->source() != Symbol::FROM_OBJECT)
 509             res = LDPR_RESOLVED_EXEC;
 510           else if (lsym->object()->pluginobj() == this)
 511             res = (is_visible_from_outside(lsym)
 512                    ? LDPR_PREVAILING_DEF
 513                    : LDPR_PREVAILING_DEF_IRONLY);
 514           else if (lsym->object()->pluginobj() != NULL)
 515             res = LDPR_RESOLVED_IR;
 516           else if (lsym->object()->is_dynamic())
 517             res = LDPR_RESOLVED_DYN;
 518           else
 519             res = LDPR_RESOLVED_EXEC;
 520         }
 521       else
 522         {
 523           // The original symbol was a definition.
 524           if (lsym->source() != Symbol::FROM_OBJECT)
 525             res = LDPR_PREEMPTED_REG;
 526           else if (lsym->object() == static_cast<const Object*>(this))
 527             res = (is_visible_from_outside(lsym)
 528                    ? LDPR_PREVAILING_DEF
 529                    : LDPR_PREVAILING_DEF_IRONLY);
 530           else
 531             res = (lsym->object()->pluginobj() != NULL
 532                    ? LDPR_PREEMPTED_IR
 533                    : LDPR_PREEMPTED_REG);
 534         }
 535       isym->resolution = res;
 536     }
 537   return LDPS_OK;
 538 }
 539
 540 // Return TRUE if the comdat group with key COMDAT_KEY from this object
 541 // should be kept.
 542
 543 bool
 544 Pluginobj::include_comdat_group(std::string comdat_key, Layout* layout)
 545 {
 546   std::pair<Comdat_map::iterator, bool> ins =
 547     this->comdat_map_.insert(std::make_pair(comdat_key, false));
 548
 549   // If this is the first time we've seen this comdat key, ask the
 550   // layout object whether it should be included.
 551   if (ins.second)
 552     ins.first->second = layout->find_or_add_kept_section(comdat_key,
 553                                                          NULL, 0, true,
 554                                                          true, NULL);
 555
 556   return ins.first->second;
 557 }
 558
 559 // Class Sized_pluginobj.
 560
 561 template<int size, bool big_endian>
 562 Sized_pluginobj<size, big_endian>::Sized_pluginobj(
 563     const std::string& name,
 564     Input_file* input_file,
 565     off_t offset,
 566     off_t filesize)
 567   : Pluginobj(name, input_file, offset, filesize)
 568 {
 569 }
 570
 571 // Read the symbols.  Not used for plugin objects.
 572
 573 template<int size, bool big_endian>
 574 void
 575 Sized_pluginobj<size, big_endian>::do_read_symbols(Read_symbols_data*)
 576 {
 577   gold_unreachable();
 578 }
 579
 580 // Lay out the input sections.  Not used for plugin objects.
 581
 582 template<int size, bool big_endian>
 583 void
 584 Sized_pluginobj<size, big_endian>::do_layout(Symbol_table*, Layout*,
 585                                              Read_symbols_data*)
 586 {
 587   gold_unreachable();
 588 }
 589
 590 // Add the symbols to the symbol table.
 591
 592 template<int size, bool big_endian>
 593 void
 594 Sized_pluginobj<size, big_endian>::do_add_symbols(Symbol_table* symtab,
 595                                                   Read_symbols_data*,
 596                                                   Layout* layout)
 597 {
 598   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
 599   unsigned char symbuf[sym_size];
 600   elfcpp::Sym<size, big_endian> sym(symbuf);
 601   elfcpp::Sym_write<size, big_endian> osym(symbuf);
 602
 603   typedef typename elfcpp::Elf_types<size>::Elf_WXword Elf_size_type;
 604
 605   this->symbols_.resize(this->nsyms_);
 606
 607   for (int i = 0; i < this->nsyms_; ++i)
 608     {
 609       const struct ld_plugin_symbol *isym = &this->syms_[i];
 610       const char* name = isym->name;
 611       const char* ver = isym->version;
 612       elfcpp::Elf_Half shndx;
 613       elfcpp::STB bind;
 614       elfcpp::STV vis;
 615
 616       if (name != NULL && name[0] == '\0')
 617         name = NULL;
 618       if (ver != NULL && ver[0] == '\0')
 619         ver = NULL;
 620
 621       switch (isym->def)
 622         {
 623         case LDPK_WEAKDEF:
 624         case LDPK_WEAKUNDEF:
 625           bind = elfcpp::STB_WEAK;
 626           break;
 627         case LDPK_DEF:
 628         case LDPK_UNDEF:
 629         case LDPK_COMMON:
 630         default:
 631           bind = elfcpp::STB_GLOBAL;
 632           break;
 633         }
 634
 635       switch (isym->def)
 636         {
 637         case LDPK_DEF:
 638         case LDPK_WEAKDEF:
 639           shndx = elfcpp::SHN_ABS;
 640           break;
 641         case LDPK_COMMON:
 642           shndx = elfcpp::SHN_COMMON;
 643           break;
 644         case LDPK_UNDEF:
 645         case LDPK_WEAKUNDEF:
 646         default:
 647           shndx = elfcpp::SHN_UNDEF;
 648           break;
 649         }
 650
 651       switch (isym->visibility)
 652         {
 653         case LDPV_PROTECTED:
 654           vis = elfcpp::STV_PROTECTED;
 655           break;
 656         case LDPV_INTERNAL:
 657           vis = elfcpp::STV_INTERNAL;
 658           break;
 659         case LDPV_HIDDEN:
 660           vis = elfcpp::STV_HIDDEN;
 661           break;
 662         case LDPV_DEFAULT:
 663         default:
 664           vis = elfcpp::STV_DEFAULT;
 665           break;
 666         }
 667
 668       if (isym->comdat_key != NULL
 669           && isym->comdat_key[0] != '\0'
 670           && !this->include_comdat_group(isym->comdat_key, layout))
 671         shndx = elfcpp::SHN_UNDEF;
 672
 673       osym.put_st_name(0);
 674       osym.put_st_value(0);
 675       osym.put_st_size(static_cast<Elf_size_type>(isym->size));
 676       osym.put_st_info(bind, elfcpp::STT_NOTYPE);
 677       osym.put_st_other(vis, 0);
 678       osym.put_st_shndx(shndx);
 679
 680       this->symbols_[i] =
 681         symtab->add_from_pluginobj<size, big_endian>(this, name, ver, &sym);
 682     }
 683 }
 684
 685 template<int size, bool big_endian>
 686 Archive::Should_include
 687 Sized_pluginobj<size, big_endian>::do_should_include_member(
 688     Symbol_table* symtab, Read_symbols_data*, std::string* why)
 689 {
 690   char* tmpbuf = NULL;
 691   size_t tmpbuflen = 0;
 692
 693   for (int i = 0; i < this->nsyms_; ++i) {
 694     const struct ld_plugin_symbol& sym = this->syms_[i];
 695     const char* name = sym.name;
 696     Symbol* symbol;
 697     Archive::Should_include t = Archive::should_include_member(symtab, name,
 698                                                                &symbol, why,
 699                                                                &tmpbuf,
 700                                                                &tmpbuflen);
 701       if (t == Archive::SHOULD_INCLUDE_YES)
 702         {
 703           if (tmpbuf != NULL)
 704             free(tmpbuf);
 705           return t;
 706         }
 707   }
 708   if (tmpbuf != NULL)
 709     free(tmpbuf);
 710   return Archive::SHOULD_INCLUDE_UNKNOWN;
 711 }
 712
 713 // Get the size of a section.  Not used for plugin objects.
 714
 715 template<int size, bool big_endian>
 716 uint64_t
 717 Sized_pluginobj<size, big_endian>::do_section_size(unsigned int)
 718 {
 719   gold_unreachable();
 720   return 0;
 721 }
 722
 723 // Get the name of a section.  Not used for plugin objects.
 724
 725 template<int size, bool big_endian>
 726 std::string
 727 Sized_pluginobj<size, big_endian>::do_section_name(unsigned int)
 728 {
 729   gold_unreachable();
 730   return std::string();
 731 }
 732
 733 // Return a view of the contents of a section.  Not used for plugin objects.
 734
 735 template<int size, bool big_endian>
 736 Object::Location
 737 Sized_pluginobj<size, big_endian>::do_section_contents(unsigned int)
 738 {
 739   Location loc(0, 0);
 740
 741   gold_unreachable();
 742   return loc;
 743 }
 744
 745 // Return section flags.  Not used for plugin objects.
 746
 747 template<int size, bool big_endian>
 748 uint64_t
 749 Sized_pluginobj<size, big_endian>::do_section_flags(unsigned int)
 750 {
 751   gold_unreachable();
 752   return 0;
 753 }
 754
 755 // Return section entsize.  Not used for plugin objects.
 756
 757 template<int size, bool big_endian>
 758 uint64_t
 759 Sized_pluginobj<size, big_endian>::do_section_entsize(unsigned int)
 760 {
 761   gold_unreachable();
 762   return 0;
 763 }
 764
 765 // Return section address.  Not used for plugin objects.
 766
 767 template<int size, bool big_endian>
 768 uint64_t
 769 Sized_pluginobj<size, big_endian>::do_section_address(unsigned int)
 770 {
 771   gold_unreachable();
 772   return 0;
 773 }
 774
 775 // Return section type.  Not used for plugin objects.
 776
 777 template<int size, bool big_endian>
 778 unsigned int
 779 Sized_pluginobj<size, big_endian>::do_section_type(unsigned int)
 780 {
 781   gold_unreachable();
 782   return 0;
 783 }
 784
 785 // Return the section link field.  Not used for plugin objects.
 786
 787 template<int size, bool big_endian>
 788 unsigned int
 789 Sized_pluginobj<size, big_endian>::do_section_link(unsigned int)
 790 {
 791   gold_unreachable();
 792   return 0;
 793 }
 794
 795 // Return the section link field.  Not used for plugin objects.
 796
 797 template<int size, bool big_endian>
 798 unsigned int
 799 Sized_pluginobj<size, big_endian>::do_section_info(unsigned int)
 800 {
 801   gold_unreachable();
 802   return 0;
 803 }
 804
 805 // Return the section alignment.  Not used for plugin objects.
 806
 807 template<int size, bool big_endian>
 808 uint64_t
 809 Sized_pluginobj<size, big_endian>::do_section_addralign(unsigned int)
 810 {
 811   gold_unreachable();
 812   return 0;
 813 }
 814
 815 // Return the Xindex structure to use.  Not used for plugin objects.
 816
 817 template<int size, bool big_endian>
 818 Xindex*
 819 Sized_pluginobj<size, big_endian>::do_initialize_xindex()
 820 {
 821   gold_unreachable();
 822   return NULL;
 823 }
 824
 825 // Get symbol counts.  Not used for plugin objects.
 826
 827 template<int size, bool big_endian>
 828 void
 829 Sized_pluginobj<size, big_endian>::do_get_global_symbol_counts(const Symbol_table*,
 830                                                    size_t*, size_t*) const
 831 {
 832   gold_unreachable();
 833 }
 834
 835 // Get symbols.  Not used for plugin objects.
 836
 837 template<int size, bool big_endian>
 838 const Object::Symbols*
 839 Sized_pluginobj<size, big_endian>::do_get_global_symbols() const
 840 {
 841   gold_unreachable();
 842 }
 843
 844 // Class Plugin_finish.  This task runs after all replacement files have
 845 // been added.  It calls each plugin's cleanup handler.
 846
 847 class Plugin_finish : public Task
 848 {
 849  public:
 850   Plugin_finish(Task_token* this_blocker, Task_token* next_blocker)
 851     : this_blocker_(this_blocker), next_blocker_(next_blocker)
 852   { }
 853
 854   ~Plugin_finish()
 855   {
 856     if (this->this_blocker_ != NULL)
 857       delete this->this_blocker_;
 858   }
 859
 860   Task_token*
 861   is_runnable()
 862   {
 863     if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 864       return this->this_blocker_;
 865     return NULL;
 866   }
 867
 868   void
 869   locks(Task_locker* tl)
 870   { tl->add(this, this->next_blocker_); }
 871
 872   void
 873   run(Workqueue*)
 874   {
 875     Plugin_manager* plugins = parameters->options().plugins();
 876     gold_assert(plugins != NULL);
 877     plugins->cleanup();
 878   }
 879
 880   std::string
 881   get_name() const
 882   { return "Plugin_finish"; }
 883
 884  private:
 885   Task_token* this_blocker_;
 886   Task_token* next_blocker_;
 887 };
 888
 889 // Class Plugin_hook.
 890
 891 Plugin_hook::~Plugin_hook()
 892 {
 893 }
 894
 895 // Return whether a Plugin_hook task is runnable.
 896
 897 Task_token*
 898 Plugin_hook::is_runnable()
 899 {
 900   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 901     return this->this_blocker_;
 902   return NULL;
 903 }
 904
 905 // Return a Task_locker for a Plugin_hook task.  We don't need any
 906 // locks here.
 907
 908 void
 909 Plugin_hook::locks(Task_locker*)
 910 {
 911 }
 912
 913 // Run the "all symbols read" plugin hook.
 914
 915 void
 916 Plugin_hook::run(Workqueue* workqueue)
 917 {
 918   gold_assert(this->options_.has_plugins());
 919   Symbol* start_sym;
 920   if (parameters->options().entry())
 921     start_sym = this->symtab_->lookup(parameters->options().entry());
 922   else
 923     start_sym = this->symtab_->lookup("_start");
 924   if (start_sym != NULL)
 925     start_sym->set_in_real_elf();
 926
 927   this->options_.plugins()->all_symbols_read(workqueue,
 928                                              this,
 929                                              this->input_objects_,
 930                                              this->symtab_,
 931                                              this->layout_,
 932                                              this->dirpath_,
 933                                              this->mapfile_,
 934                                              &this->this_blocker_);
 935   workqueue->queue_soon(new Plugin_finish(this->this_blocker_,
 936                                           this->next_blocker_));
 937 }
 938
 939 // The C interface routines called by the plugins.
 940
 941 #ifdef ENABLE_PLUGINS
 942
 943 // Register a claim-file handler.
 944
 945 static enum ld_plugin_status
 946 register_claim_file(ld_plugin_claim_file_handler handler)
 947 {
 948   gold_assert(parameters->options().has_plugins());
 949   parameters->options().plugins()->set_claim_file_handler(handler);
 950   return LDPS_OK;
 951 }
 952
 953 // Register an all-symbols-read handler.
 954
 955 static enum ld_plugin_status
 956 register_all_symbols_read(ld_plugin_all_symbols_read_handler handler)
 957 {
 958   gold_assert(parameters->options().has_plugins());
 959   parameters->options().plugins()->set_all_symbols_read_handler(handler);
 960   return LDPS_OK;
 961 }
 962
 963 // Register a cleanup handler.
 964
 965 static enum ld_plugin_status
 966 register_cleanup(ld_plugin_cleanup_handler handler)
 967 {
 968   gold_assert(parameters->options().has_plugins());
 969   parameters->options().plugins()->set_cleanup_handler(handler);
 970   return LDPS_OK;
 971 }
 972
 973 // Add symbols from a plugin-claimed input file.
 974
 975 static enum ld_plugin_status
 976 add_symbols(void* handle, int nsyms, const ld_plugin_symbol *syms)
 977 {
 978   gold_assert(parameters->options().has_plugins());
 979   Pluginobj* obj = parameters->options().plugins()->make_plugin_object(
 980       static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
 981   if (obj == NULL)
 982     return LDPS_ERR;
 983   obj->store_incoming_symbols(nsyms, syms);
 984   return LDPS_OK;
 985 }
 986
 987 // Get the input file information with an open (possibly re-opened)
 988 // file descriptor.
 989
 990 static enum ld_plugin_status
 991 get_input_file(const void *handle, struct ld_plugin_input_file *file)
 992 {
 993   gold_assert(parameters->options().has_plugins());
 994   unsigned int obj_index =
 995       static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle));
 996   return parameters->options().plugins()->get_input_file(obj_index, file);
 997 }
 998
 999 // Release the input file.
1000
1001 static enum ld_plugin_status
1002 release_input_file(const void *handle)
1003 {
1004   gold_assert(parameters->options().has_plugins());
1005   unsigned int obj_index =
1006       static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle));
1007   return parameters->options().plugins()->release_input_file(obj_index);
1008 }
1009
1010 // Get the symbol resolution info for a plugin-claimed input file.
1011
1012 static enum ld_plugin_status
1013 get_symbols(const void * handle, int nsyms, ld_plugin_symbol* syms)
1014 {
1015   gold_assert(parameters->options().has_plugins());
1016   Pluginobj* obj = parameters->options().plugins()->object(
1017       static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
1018   if (obj == NULL)
1019     return LDPS_ERR;
1020   return obj->get_symbol_resolution_info(nsyms, syms);
1021 }
1022
1023 // Add a new (real) input file generated by a plugin.
1024
1025 static enum ld_plugin_status
1026 add_input_file(const char *pathname)
1027 {
1028   gold_assert(parameters->options().has_plugins());
1029   return parameters->options().plugins()->add_input_file(pathname, false);
1030 }
1031
1032 // Add a new (real) library required by a plugin.
1033
1034 static enum ld_plugin_status
1035 add_input_library(const char *pathname)
1036 {
1037   gold_assert(parameters->options().has_plugins());
1038   return parameters->options().plugins()->add_input_file(pathname, true);
1039 }
1040
1041 // Issue a diagnostic message from a plugin.
1042
1043 static enum ld_plugin_status
1044 message(int level, const char * format, ...)
1045 {
1046   va_list args;
1047   va_start(args, format);
1048
1049   switch (level)
1050     {
1051     case LDPL_INFO:
1052       parameters->errors()->info(format, args);
1053       break;
1054     case LDPL_WARNING:
1055       parameters->errors()->warning(format, args);
1056       break;
1057     case LDPL_ERROR:
1058     default:
1059       parameters->errors()->error(format, args);
1060       break;
1061     case LDPL_FATAL:
1062       parameters->errors()->fatal(format, args);
1063       break;
1064     }
1065
1066   va_end(args);
1067   return LDPS_OK;
1068 }
1069
1070 #endif // ENABLE_PLUGINS
1071
1072 // Allocate a Pluginobj object of the appropriate size and endianness.
1073
1074 static Pluginobj*
1075 make_sized_plugin_object(Input_file* input_file, off_t offset, off_t filesize)
1076 {
1077   Pluginobj* obj = NULL;
1078
1079   parameters_force_valid_target();
1080   const Target& target(parameters->target());
1081
1082   if (target.get_size() == 32)
1083     {
1084       if (target.is_big_endian())
1085 #ifdef HAVE_TARGET_32_BIG
1086         obj = new Sized_pluginobj<32, true>(input_file->filename(),
1087                                             input_file, offset, filesize);
1088 #else
1089         gold_error(_("%s: not configured to support "
1090                      "32-bit big-endian object"),
1091                    input_file->filename().c_str());
1092 #endif
1093       else
1094 #ifdef HAVE_TARGET_32_LITTLE
1095         obj = new Sized_pluginobj<32, false>(input_file->filename(),
1096                                              input_file, offset, filesize);
1097 #else
1098         gold_error(_("%s: not configured to support "
1099                      "32-bit little-endian object"),
1100                    input_file->filename().c_str());
1101 #endif
1102     }
1103   else if (target.get_size() == 64)
1104     {
1105       if (target.is_big_endian())
1106 #ifdef HAVE_TARGET_64_BIG
1107         obj = new Sized_pluginobj<64, true>(input_file->filename(),
1108                                             input_file, offset, filesize);
1109 #else
1110         gold_error(_("%s: not configured to support "
1111                      "64-bit big-endian object"),
1112                    input_file->filename().c_str());
1113 #endif
1114       else
1115 #ifdef HAVE_TARGET_64_LITTLE
1116         obj = new Sized_pluginobj<64, false>(input_file->filename(),
1117                                              input_file, offset, filesize);
1118 #else
1119         gold_error(_("%s: not configured to support "
1120                      "64-bit little-endian object"),
1121                    input_file->filename().c_str());
1122 #endif
1123     }
1124
1125   gold_assert(obj != NULL);
1126   return obj;
1127 }
1128
1129 } // End namespace gold.