1 // plugin.cc -- plugin manager for gold -*- C++ -*-
3 // Copyright 2008, 2009 Free Software Foundation, Inc.
4 // Written by Cary Coutant <ccoutant@google.com>.
6 // This file is part of gold.
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.
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.
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.
31 #include "parameters.h"
47 // The linker's exported interfaces.
52 static enum ld_plugin_status
53 register_claim_file(ld_plugin_claim_file_handler handler);
55 static enum ld_plugin_status
56 register_all_symbols_read(ld_plugin_all_symbols_read_handler handler);
58 static enum ld_plugin_status
59 register_cleanup(ld_plugin_cleanup_handler handler);
61 static enum ld_plugin_status
62 add_symbols(void *handle, int nsyms, const struct ld_plugin_symbol *syms);
64 static enum ld_plugin_status
65 get_input_file(const void *handle, struct ld_plugin_input_file *file);
67 static enum ld_plugin_status
68 release_input_file(const void *handle);
70 static enum ld_plugin_status
71 get_symbols(const void *handle, int nsyms, struct ld_plugin_symbol *syms);
73 static enum ld_plugin_status
74 add_input_file(char *pathname);
76 static enum ld_plugin_status
77 message(int level, const char *format, ...);
81 #endif // ENABLE_PLUGINS
83 static Pluginobj* make_sized_plugin_object(Input_file* input_file,
84 off_t offset, off_t filesize);
88 // Load one plugin library.
94 // Load the plugin library.
95 // FIXME: Look for the library in standard locations.
96 this->handle_ = dlopen(this->filename_.c_str(), RTLD_NOW);
97 if (this->handle_ == NULL)
99 gold_error(_("%s: could not load plugin library"),
100 this->filename_.c_str());
104 // Find the plugin's onload entry point.
105 ld_plugin_onload onload = reinterpret_cast<ld_plugin_onload>
106 (dlsym(this->handle_, "onload"));
109 gold_error(_("%s: could not find onload entry point"),
110 this->filename_.c_str());
114 // Get the linker's version number.
115 const char* ver = get_version_string();
118 sscanf(ver, "%d.%d", &major, &minor);
120 // Allocate and populate a transfer vector.
121 const int tv_fixed_size = 13;
122 int tv_size = this->args_.size() + tv_fixed_size;
123 ld_plugin_tv *tv = new ld_plugin_tv[tv_size];
125 // Put LDPT_MESSAGE at the front of the list so the plugin can use it
126 // while processing subsequent entries.
128 tv[i].tv_tag = LDPT_MESSAGE;
129 tv[i].tv_u.tv_message = message;
132 tv[i].tv_tag = LDPT_API_VERSION;
133 tv[i].tv_u.tv_val = LD_PLUGIN_API_VERSION;
136 tv[i].tv_tag = LDPT_GOLD_VERSION;
137 tv[i].tv_u.tv_val = major * 100 + minor;
140 tv[i].tv_tag = LDPT_LINKER_OUTPUT;
141 if (parameters->options().relocatable())
142 tv[i].tv_u.tv_val = LDPO_REL;
143 else if (parameters->options().shared())
144 tv[i].tv_u.tv_val = LDPO_DYN;
146 tv[i].tv_u.tv_val = LDPO_EXEC;
148 for (unsigned int j = 0; j < this->args_.size(); ++j)
151 tv[i].tv_tag = LDPT_OPTION;
152 tv[i].tv_u.tv_string = this->args_[j].c_str();
156 tv[i].tv_tag = LDPT_REGISTER_CLAIM_FILE_HOOK;
157 tv[i].tv_u.tv_register_claim_file = register_claim_file;
160 tv[i].tv_tag = LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK;
161 tv[i].tv_u.tv_register_all_symbols_read = register_all_symbols_read;
164 tv[i].tv_tag = LDPT_REGISTER_CLEANUP_HOOK;
165 tv[i].tv_u.tv_register_cleanup = register_cleanup;
168 tv[i].tv_tag = LDPT_ADD_SYMBOLS;
169 tv[i].tv_u.tv_add_symbols = add_symbols;
172 tv[i].tv_tag = LDPT_GET_INPUT_FILE;
173 tv[i].tv_u.tv_get_input_file = get_input_file;
176 tv[i].tv_tag = LDPT_RELEASE_INPUT_FILE;
177 tv[i].tv_u.tv_release_input_file = release_input_file;
180 tv[i].tv_tag = LDPT_GET_SYMBOLS;
181 tv[i].tv_u.tv_get_symbols = get_symbols;
184 tv[i].tv_tag = LDPT_ADD_INPUT_FILE;
185 tv[i].tv_u.tv_add_input_file = add_input_file;
188 tv[i].tv_tag = LDPT_NULL;
189 tv[i].tv_u.tv_val = 0;
191 gold_assert(i == tv_size - 1);
193 // Call the onload entry point.
197 #endif // ENABLE_PLUGINS
200 // Call the plugin claim-file handler.
203 Plugin::claim_file(struct ld_plugin_input_file *plugin_input_file)
207 if (this->claim_file_handler_ != NULL)
209 (*this->claim_file_handler_)(plugin_input_file, &claimed);
216 // Call the all-symbols-read handler.
219 Plugin::all_symbols_read()
221 if (this->all_symbols_read_handler_ != NULL)
222 (*this->all_symbols_read_handler_)();
225 // Call the cleanup handler.
230 if (this->cleanup_handler_ != NULL)
231 (*this->cleanup_handler_)();
234 // Plugin_manager methods.
236 Plugin_manager::~Plugin_manager()
238 for (Plugin_list::iterator p = this->plugins_.begin();
239 p != this->plugins_.end();
242 this->plugins_.clear();
243 for (Object_list::iterator obj = this->objects_.begin();
244 obj != this->objects_.end();
247 this->objects_.clear();
250 // Load all plugin libraries.
253 Plugin_manager::load_plugins()
255 for (this->current_ = this->plugins_.begin();
256 this->current_ != this->plugins_.end();
258 (*this->current_)->load();
261 // Call the plugin claim-file handlers in turn to see if any claim the file.
264 Plugin_manager::claim_file(Input_file* input_file, off_t offset,
267 if (this->in_replacement_phase_)
270 unsigned int handle = this->objects_.size();
271 this->input_file_ = input_file;
272 this->plugin_input_file_.name = input_file->filename().c_str();
273 this->plugin_input_file_.fd = input_file->file().descriptor();
274 this->plugin_input_file_.offset = offset;
275 this->plugin_input_file_.filesize = filesize;
276 this->plugin_input_file_.handle = reinterpret_cast<void*>(handle);
278 for (this->current_ = this->plugins_.begin();
279 this->current_ != this->plugins_.end();
282 if ((*this->current_)->claim_file(&this->plugin_input_file_))
284 if (this->objects_.size() > handle)
285 return this->objects_[handle];
287 // If the plugin claimed the file but did not call the
288 // add_symbols callback, we need to create the Pluginobj now.
289 Pluginobj* obj = this->make_plugin_object(handle);
297 // Call the all-symbols-read handlers.
300 Plugin_manager::all_symbols_read(Workqueue* workqueue, Task* task,
301 Input_objects* input_objects,
302 Symbol_table* symtab, Layout* layout,
303 Dirsearch* dirpath, Mapfile* mapfile,
304 Task_token** last_blocker)
306 this->in_replacement_phase_ = true;
307 this->workqueue_ = workqueue;
309 this->input_objects_ = input_objects;
310 this->symtab_ = symtab;
311 this->layout_ = layout;
312 this->dirpath_ = dirpath;
313 this->mapfile_ = mapfile;
314 this->this_blocker_ = NULL;
316 for (this->current_ = this->plugins_.begin();
317 this->current_ != this->plugins_.end();
319 (*this->current_)->all_symbols_read();
321 *last_blocker = this->this_blocker_;
324 // Layout deferred objects.
327 Plugin_manager::layout_deferred_objects()
329 Deferred_layout_list::iterator obj;
331 for (obj = this->deferred_layout_objects_.begin();
332 obj != this->deferred_layout_objects_.end();
334 (*obj)->layout_deferred_sections(this->layout_);
337 // Call the cleanup handlers.
340 Plugin_manager::cleanup()
342 if (this->cleanup_done_)
344 for (this->current_ = this->plugins_.begin();
345 this->current_ != this->plugins_.end();
347 (*this->current_)->cleanup();
348 this->cleanup_done_ = true;
351 // Make a new Pluginobj object. This is called when the plugin calls
352 // the add_symbols API.
355 Plugin_manager::make_plugin_object(unsigned int handle)
357 // Make sure we aren't asked to make an object for the same handle twice.
358 if (this->objects_.size() != handle)
361 Pluginobj* obj = make_sized_plugin_object(this->input_file_,
362 this->plugin_input_file_.offset,
363 this->plugin_input_file_.filesize);
364 this->objects_.push_back(obj);
368 // Get the input file information with an open (possibly re-opened)
372 Plugin_manager::get_input_file(unsigned int handle,
373 struct ld_plugin_input_file *file)
375 Pluginobj* obj = this->object(handle);
377 return LDPS_BAD_HANDLE;
379 obj->lock(this->task_);
380 file->name = obj->filename().c_str();
381 file->fd = obj->descriptor();
382 file->offset = obj->offset();
383 file->filesize = obj->filesize();
384 file->handle = reinterpret_cast<void*>(handle);
388 // Release the input file.
391 Plugin_manager::release_input_file(unsigned int handle)
393 Pluginobj* obj = this->object(handle);
395 return LDPS_BAD_HANDLE;
397 obj->unlock(this->task_);
401 // Add a new input file.
404 Plugin_manager::add_input_file(char *pathname)
406 Input_file_argument file(pathname, false, "", false, this->options_);
407 Input_argument* input_argument = new Input_argument(file);
408 Task_token* next_blocker = new Task_token(true);
409 next_blocker->add_blocker();
410 this->workqueue_->queue_soon(new Read_symbols(this->input_objects_,
419 this->this_blocker_ = next_blocker;
425 Pluginobj::Pluginobj(const std::string& name, Input_file* input_file,
426 off_t offset, off_t filesize)
427 : Object(name, input_file, false, offset),
428 nsyms_(0), syms_(NULL), symbols_(), filesize_(filesize), comdat_map_()
432 // Return TRUE if a defined symbol might be reachable from outside the
433 // universe of claimed objects.
436 is_visible_from_outside(Symbol* lsym)
438 if (lsym->in_real_elf())
440 if (parameters->options().relocatable())
442 if (parameters->options().export_dynamic() || parameters->options().shared())
443 return lsym->is_externally_visible();
447 // Get symbol resolution info.
450 Pluginobj::get_symbol_resolution_info(int nsyms, ld_plugin_symbol* syms) const
452 if (nsyms > this->nsyms_)
454 for (int i = 0; i < nsyms; i++)
456 ld_plugin_symbol* isym = &syms[i];
457 Symbol* lsym = this->symbols_[i];
458 ld_plugin_symbol_resolution res = LDPR_UNKNOWN;
460 if (lsym->is_undefined())
461 // The symbol remains undefined.
463 else if (isym->def == LDPK_UNDEF
464 || isym->def == LDPK_WEAKUNDEF
465 || isym->def == LDPK_COMMON)
467 // The original symbol was undefined or common.
468 if (lsym->source() != Symbol::FROM_OBJECT)
469 res = LDPR_RESOLVED_EXEC;
470 else if (lsym->object()->pluginobj() != NULL)
471 res = LDPR_RESOLVED_IR;
472 else if (lsym->object()->is_dynamic())
473 res = LDPR_RESOLVED_DYN;
475 res = LDPR_RESOLVED_EXEC;
479 // The original symbol was a definition.
480 if (lsym->source() != Symbol::FROM_OBJECT)
481 res = LDPR_PREEMPTED_REG;
482 else if (lsym->object() == static_cast<const Object*>(this))
483 res = (is_visible_from_outside(lsym)
484 ? LDPR_PREVAILING_DEF
485 : LDPR_PREVAILING_DEF_IRONLY);
487 res = (lsym->object()->pluginobj() != NULL
489 : LDPR_PREEMPTED_REG);
491 isym->resolution = res;
496 // Return TRUE if the comdat group with key COMDAT_KEY from this object
500 Pluginobj::include_comdat_group(std::string comdat_key, Layout* layout)
502 std::pair<Comdat_map::iterator, bool> ins =
503 this->comdat_map_.insert(std::make_pair(comdat_key, false));
505 // If this is the first time we've seen this comdat key, ask the
506 // layout object whether it should be included.
509 Kept_section to_add(NULL, 1, true);
510 ins.first->second = layout->find_or_add_kept_section(comdat_key,
515 return ins.first->second;
518 // Class Sized_pluginobj.
520 template<int size, bool big_endian>
521 Sized_pluginobj<size, big_endian>::Sized_pluginobj(
522 const std::string& name,
523 Input_file* input_file,
526 : Pluginobj(name, input_file, offset, filesize)
530 // Read the symbols. Not used for plugin objects.
532 template<int size, bool big_endian>
534 Sized_pluginobj<size, big_endian>::do_read_symbols(Read_symbols_data*)
539 // Lay out the input sections. Not used for plugin objects.
541 template<int size, bool big_endian>
543 Sized_pluginobj<size, big_endian>::do_layout(Symbol_table*, Layout*,
549 // Add the symbols to the symbol table.
551 template<int size, bool big_endian>
553 Sized_pluginobj<size, big_endian>::do_add_symbols(Symbol_table* symtab,
557 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
558 unsigned char symbuf[sym_size];
559 elfcpp::Sym<size, big_endian> sym(symbuf);
560 elfcpp::Sym_write<size, big_endian> osym(symbuf);
562 typedef typename elfcpp::Elf_types<size>::Elf_WXword Elf_size_type;
564 this->symbols_.resize(this->nsyms_);
566 for (int i = 0; i < this->nsyms_; ++i)
568 const struct ld_plugin_symbol *isym = &this->syms_[i];
569 const char* name = isym->name;
570 const char* ver = isym->version;
571 elfcpp::Elf_Half shndx;
575 if (name != NULL && name[0] == '\0')
577 if (ver != NULL && ver[0] == '\0')
584 bind = elfcpp::STB_WEAK;
590 bind = elfcpp::STB_GLOBAL;
598 shndx = elfcpp::SHN_ABS;
601 shndx = elfcpp::SHN_COMMON;
606 shndx = elfcpp::SHN_UNDEF;
610 switch (isym->visibility)
613 vis = elfcpp::STV_DEFAULT;
616 vis = elfcpp::STV_DEFAULT;
619 vis = elfcpp::STV_DEFAULT;
623 vis = elfcpp::STV_DEFAULT;
627 if (isym->comdat_key != NULL
628 && isym->comdat_key[0] != '\0'
629 && !this->include_comdat_group(isym->comdat_key, layout))
630 shndx = elfcpp::SHN_UNDEF;
633 osym.put_st_value(0);
634 osym.put_st_size(static_cast<Elf_size_type>(isym->size));
635 osym.put_st_info(bind, elfcpp::STT_NOTYPE);
636 osym.put_st_other(vis, 0);
637 osym.put_st_shndx(shndx);
640 symtab->add_from_pluginobj<size, big_endian>(this, name, ver, &sym);
644 // Get the size of a section. Not used for plugin objects.
646 template<int size, bool big_endian>
648 Sized_pluginobj<size, big_endian>::do_section_size(unsigned int)
654 // Get the name of a section. Not used for plugin objects.
656 template<int size, bool big_endian>
658 Sized_pluginobj<size, big_endian>::do_section_name(unsigned int)
661 return std::string();
664 // Return a view of the contents of a section. Not used for plugin objects.
666 template<int size, bool big_endian>
668 Sized_pluginobj<size, big_endian>::do_section_contents(unsigned int)
676 // Return section flags. Not used for plugin objects.
678 template<int size, bool big_endian>
680 Sized_pluginobj<size, big_endian>::do_section_flags(unsigned int)
686 // Return section address. Not used for plugin objects.
688 template<int size, bool big_endian>
690 Sized_pluginobj<size, big_endian>::do_section_address(unsigned int)
696 // Return section type. Not used for plugin objects.
698 template<int size, bool big_endian>
700 Sized_pluginobj<size, big_endian>::do_section_type(unsigned int)
706 // Return the section link field. Not used for plugin objects.
708 template<int size, bool big_endian>
710 Sized_pluginobj<size, big_endian>::do_section_link(unsigned int)
716 // Return the section link field. Not used for plugin objects.
718 template<int size, bool big_endian>
720 Sized_pluginobj<size, big_endian>::do_section_info(unsigned int)
726 // Return the section alignment. Not used for plugin objects.
728 template<int size, bool big_endian>
730 Sized_pluginobj<size, big_endian>::do_section_addralign(unsigned int)
736 // Return the Xindex structure to use. Not used for plugin objects.
738 template<int size, bool big_endian>
740 Sized_pluginobj<size, big_endian>::do_initialize_xindex()
746 // Get symbol counts. Not used for plugin objects.
748 template<int size, bool big_endian>
750 Sized_pluginobj<size, big_endian>::do_get_global_symbol_counts(const Symbol_table*,
751 size_t*, size_t*) const
756 // Class Plugin_finish. This task runs after all replacement files have
757 // been added. It calls each plugin's cleanup handler.
759 class Plugin_finish : public Task
762 Plugin_finish(Task_token* this_blocker, Task_token* next_blocker)
763 : this_blocker_(this_blocker), next_blocker_(next_blocker)
768 if (this->this_blocker_ != NULL)
769 delete this->this_blocker_;
775 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
776 return this->this_blocker_;
781 locks(Task_locker* tl)
782 { tl->add(this, this->next_blocker_); }
787 Plugin_manager* plugins = parameters->options().plugins();
788 gold_assert(plugins != NULL);
794 { return "Plugin_finish"; }
797 Task_token* this_blocker_;
798 Task_token* next_blocker_;
801 // Class Plugin_hook.
803 Plugin_hook::~Plugin_hook()
807 // Return whether a Plugin_hook task is runnable.
810 Plugin_hook::is_runnable()
812 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
813 return this->this_blocker_;
817 // Return a Task_locker for a Plugin_hook task. We don't need any
821 Plugin_hook::locks(Task_locker*)
825 // Run the "all symbols read" plugin hook.
828 Plugin_hook::run(Workqueue* workqueue)
830 gold_assert(this->options_.has_plugins());
831 this->options_.plugins()->all_symbols_read(workqueue,
833 this->input_objects_,
838 &this->this_blocker_);
839 workqueue->queue_soon(new Plugin_finish(this->this_blocker_,
840 this->next_blocker_));
843 // The C interface routines called by the plugins.
845 #ifdef ENABLE_PLUGINS
847 // Register a claim-file handler.
849 static enum ld_plugin_status
850 register_claim_file(ld_plugin_claim_file_handler handler)
852 gold_assert(parameters->options().has_plugins());
853 parameters->options().plugins()->set_claim_file_handler(handler);
857 // Register an all-symbols-read handler.
859 static enum ld_plugin_status
860 register_all_symbols_read(ld_plugin_all_symbols_read_handler handler)
862 gold_assert(parameters->options().has_plugins());
863 parameters->options().plugins()->set_all_symbols_read_handler(handler);
867 // Register a cleanup handler.
869 static enum ld_plugin_status
870 register_cleanup(ld_plugin_cleanup_handler handler)
872 gold_assert(parameters->options().has_plugins());
873 parameters->options().plugins()->set_cleanup_handler(handler);
877 // Add symbols from a plugin-claimed input file.
879 static enum ld_plugin_status
880 add_symbols(void* handle, int nsyms, const ld_plugin_symbol *syms)
882 gold_assert(parameters->options().has_plugins());
883 Pluginobj* obj = parameters->options().plugins()->make_plugin_object(
884 static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
887 obj->store_incoming_symbols(nsyms, syms);
891 // Get the input file information with an open (possibly re-opened)
894 static enum ld_plugin_status
895 get_input_file(const void *handle, struct ld_plugin_input_file *file)
897 gold_assert(parameters->options().has_plugins());
898 unsigned int obj_index =
899 static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle));
900 return parameters->options().plugins()->get_input_file(obj_index, file);
903 // Release the input file.
905 static enum ld_plugin_status
906 release_input_file(const void *handle)
908 gold_assert(parameters->options().has_plugins());
909 unsigned int obj_index =
910 static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle));
911 return parameters->options().plugins()->release_input_file(obj_index);
914 // Get the symbol resolution info for a plugin-claimed input file.
916 static enum ld_plugin_status
917 get_symbols(const void * handle, int nsyms, ld_plugin_symbol* syms)
919 gold_assert(parameters->options().has_plugins());
920 Pluginobj* obj = parameters->options().plugins()->object(
921 static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
924 return obj->get_symbol_resolution_info(nsyms, syms);
927 // Add a new (real) input file generated by a plugin.
929 static enum ld_plugin_status
930 add_input_file(char *pathname)
932 gold_assert(parameters->options().has_plugins());
933 return parameters->options().plugins()->add_input_file(pathname);
936 // Issue a diagnostic message from a plugin.
938 static enum ld_plugin_status
939 message(int level, const char * format, ...)
942 va_start(args, format);
947 parameters->errors()->info(format, args);
950 parameters->errors()->warning(format, args);
954 parameters->errors()->error(format, args);
957 parameters->errors()->fatal(format, args);
965 #endif // ENABLE_PLUGINS
967 // Allocate a Pluginobj object of the appropriate size and endianness.
970 make_sized_plugin_object(Input_file* input_file, off_t offset, off_t filesize)
973 Pluginobj* obj = NULL;
975 if (parameters->target_valid())
976 target = const_cast<Target*>(¶meters->target());
978 target = const_cast<Target*>(¶meters->default_target());
980 if (target->get_size() == 32)
982 if (target->is_big_endian())
983 #ifdef HAVE_TARGET_32_BIG
984 obj = new Sized_pluginobj<32, true>(input_file->filename(),
985 input_file, offset, filesize);
987 gold_error(_("%s: not configured to support "
988 "32-bit big-endian object"),
989 input_file->filename().c_str());
992 #ifdef HAVE_TARGET_32_LITTLE
993 obj = new Sized_pluginobj<32, false>(input_file->filename(),
994 input_file, offset, filesize);
996 gold_error(_("%s: not configured to support "
997 "32-bit little-endian object"),
998 input_file->filename().c_str());
1001 else if (target->get_size() == 64)
1003 if (target->is_big_endian())
1004 #ifdef HAVE_TARGET_64_BIG
1005 obj = new Sized_pluginobj<64, true>(input_file->filename(),
1006 input_file, offset, filesize);
1008 gold_error(_("%s: not configured to support "
1009 "64-bit big-endian object"),
1010 input_file->filename().c_str());
1013 #ifdef HAVE_TARGET_64_LITTLE
1014 obj = new Sized_pluginobj<64, false>(input_file->filename(),
1015 input_file, offset, filesize);
1017 gold_error(_("%s: not configured to support "
1018 "64-bit little-endian object"),
1019 input_file->filename().c_str());
1023 gold_assert(obj != NULL);
1024 obj->set_target(target);
1028 } // End namespace gold.