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 if (this->layout_->incremental_inputs())
411 gold_error(_("Input files added by plug-ins in --incremental mode not "
412 "supported yet.\n"));
413 this->workqueue_->queue_soon(new Read_symbols(this->input_objects_,
423 this->this_blocker_ = next_blocker;
429 Pluginobj::Pluginobj(const std::string& name, Input_file* input_file,
430 off_t offset, off_t filesize)
431 : Object(name, input_file, false, offset),
432 nsyms_(0), syms_(NULL), symbols_(), filesize_(filesize), comdat_map_()
436 // Return TRUE if a defined symbol might be reachable from outside the
437 // universe of claimed objects.
440 is_visible_from_outside(Symbol* lsym)
442 if (lsym->in_real_elf())
444 if (parameters->options().relocatable())
446 if (parameters->options().export_dynamic() || parameters->options().shared())
447 return lsym->is_externally_visible();
451 // Get symbol resolution info.
454 Pluginobj::get_symbol_resolution_info(int nsyms, ld_plugin_symbol* syms) const
456 if (nsyms > this->nsyms_)
458 for (int i = 0; i < nsyms; i++)
460 ld_plugin_symbol* isym = &syms[i];
461 Symbol* lsym = this->symbols_[i];
462 ld_plugin_symbol_resolution res = LDPR_UNKNOWN;
464 if (lsym->is_undefined())
465 // The symbol remains undefined.
467 else if (isym->def == LDPK_UNDEF
468 || isym->def == LDPK_WEAKUNDEF
469 || isym->def == LDPK_COMMON)
471 // The original symbol was undefined or common.
472 if (lsym->source() != Symbol::FROM_OBJECT)
473 res = LDPR_RESOLVED_EXEC;
474 else if (lsym->object()->pluginobj() != NULL)
475 res = LDPR_RESOLVED_IR;
476 else if (lsym->object()->is_dynamic())
477 res = LDPR_RESOLVED_DYN;
479 res = LDPR_RESOLVED_EXEC;
483 // The original symbol was a definition.
484 if (lsym->source() != Symbol::FROM_OBJECT)
485 res = LDPR_PREEMPTED_REG;
486 else if (lsym->object() == static_cast<const Object*>(this))
487 res = (is_visible_from_outside(lsym)
488 ? LDPR_PREVAILING_DEF
489 : LDPR_PREVAILING_DEF_IRONLY);
491 res = (lsym->object()->pluginobj() != NULL
493 : LDPR_PREEMPTED_REG);
495 isym->resolution = res;
500 // Return TRUE if the comdat group with key COMDAT_KEY from this object
504 Pluginobj::include_comdat_group(std::string comdat_key, Layout* layout)
506 std::pair<Comdat_map::iterator, bool> ins =
507 this->comdat_map_.insert(std::make_pair(comdat_key, false));
509 // If this is the first time we've seen this comdat key, ask the
510 // layout object whether it should be included.
512 ins.first->second = layout->find_or_add_kept_section(comdat_key,
516 return ins.first->second;
519 // Class Sized_pluginobj.
521 template<int size, bool big_endian>
522 Sized_pluginobj<size, big_endian>::Sized_pluginobj(
523 const std::string& name,
524 Input_file* input_file,
527 : Pluginobj(name, input_file, offset, filesize)
531 // Read the symbols. Not used for plugin objects.
533 template<int size, bool big_endian>
535 Sized_pluginobj<size, big_endian>::do_read_symbols(Read_symbols_data*)
540 // Lay out the input sections. Not used for plugin objects.
542 template<int size, bool big_endian>
544 Sized_pluginobj<size, big_endian>::do_layout(Symbol_table*, Layout*,
550 // Add the symbols to the symbol table.
552 template<int size, bool big_endian>
554 Sized_pluginobj<size, big_endian>::do_add_symbols(Symbol_table* symtab,
558 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
559 unsigned char symbuf[sym_size];
560 elfcpp::Sym<size, big_endian> sym(symbuf);
561 elfcpp::Sym_write<size, big_endian> osym(symbuf);
563 typedef typename elfcpp::Elf_types<size>::Elf_WXword Elf_size_type;
565 this->symbols_.resize(this->nsyms_);
567 for (int i = 0; i < this->nsyms_; ++i)
569 const struct ld_plugin_symbol *isym = &this->syms_[i];
570 const char* name = isym->name;
571 const char* ver = isym->version;
572 elfcpp::Elf_Half shndx;
576 if (name != NULL && name[0] == '\0')
578 if (ver != NULL && ver[0] == '\0')
585 bind = elfcpp::STB_WEAK;
591 bind = elfcpp::STB_GLOBAL;
599 shndx = elfcpp::SHN_ABS;
602 shndx = elfcpp::SHN_COMMON;
607 shndx = elfcpp::SHN_UNDEF;
611 switch (isym->visibility)
614 vis = elfcpp::STV_DEFAULT;
617 vis = elfcpp::STV_DEFAULT;
620 vis = elfcpp::STV_DEFAULT;
624 vis = elfcpp::STV_DEFAULT;
628 if (isym->comdat_key != NULL
629 && isym->comdat_key[0] != '\0'
630 && !this->include_comdat_group(isym->comdat_key, layout))
631 shndx = elfcpp::SHN_UNDEF;
634 osym.put_st_value(0);
635 osym.put_st_size(static_cast<Elf_size_type>(isym->size));
636 osym.put_st_info(bind, elfcpp::STT_NOTYPE);
637 osym.put_st_other(vis, 0);
638 osym.put_st_shndx(shndx);
641 symtab->add_from_pluginobj<size, big_endian>(this, name, ver, &sym);
645 // Get the size of a section. Not used for plugin objects.
647 template<int size, bool big_endian>
649 Sized_pluginobj<size, big_endian>::do_section_size(unsigned int)
655 // Get the name of a section. Not used for plugin objects.
657 template<int size, bool big_endian>
659 Sized_pluginobj<size, big_endian>::do_section_name(unsigned int)
662 return std::string();
665 // Return a view of the contents of a section. Not used for plugin objects.
667 template<int size, bool big_endian>
669 Sized_pluginobj<size, big_endian>::do_section_contents(unsigned int)
677 // Return section flags. Not used for plugin objects.
679 template<int size, bool big_endian>
681 Sized_pluginobj<size, big_endian>::do_section_flags(unsigned int)
687 // Return section entsize. Not used for plugin objects.
689 template<int size, bool big_endian>
691 Sized_pluginobj<size, big_endian>::do_section_entsize(unsigned int)
697 // Return section address. Not used for plugin objects.
699 template<int size, bool big_endian>
701 Sized_pluginobj<size, big_endian>::do_section_address(unsigned int)
707 // Return section type. Not used for plugin objects.
709 template<int size, bool big_endian>
711 Sized_pluginobj<size, big_endian>::do_section_type(unsigned int)
717 // Return the section link field. Not used for plugin objects.
719 template<int size, bool big_endian>
721 Sized_pluginobj<size, big_endian>::do_section_link(unsigned int)
727 // Return the section link field. Not used for plugin objects.
729 template<int size, bool big_endian>
731 Sized_pluginobj<size, big_endian>::do_section_info(unsigned int)
737 // Return the section alignment. Not used for plugin objects.
739 template<int size, bool big_endian>
741 Sized_pluginobj<size, big_endian>::do_section_addralign(unsigned int)
747 // Return the Xindex structure to use. Not used for plugin objects.
749 template<int size, bool big_endian>
751 Sized_pluginobj<size, big_endian>::do_initialize_xindex()
757 // Get symbol counts. Not used for plugin objects.
759 template<int size, bool big_endian>
761 Sized_pluginobj<size, big_endian>::do_get_global_symbol_counts(const Symbol_table*,
762 size_t*, size_t*) const
767 // Class Plugin_finish. This task runs after all replacement files have
768 // been added. It calls each plugin's cleanup handler.
770 class Plugin_finish : public Task
773 Plugin_finish(Task_token* this_blocker, Task_token* next_blocker)
774 : this_blocker_(this_blocker), next_blocker_(next_blocker)
779 if (this->this_blocker_ != NULL)
780 delete this->this_blocker_;
786 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
787 return this->this_blocker_;
792 locks(Task_locker* tl)
793 { tl->add(this, this->next_blocker_); }
798 Plugin_manager* plugins = parameters->options().plugins();
799 gold_assert(plugins != NULL);
805 { return "Plugin_finish"; }
808 Task_token* this_blocker_;
809 Task_token* next_blocker_;
812 // Class Plugin_hook.
814 Plugin_hook::~Plugin_hook()
818 // Return whether a Plugin_hook task is runnable.
821 Plugin_hook::is_runnable()
823 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
824 return this->this_blocker_;
828 // Return a Task_locker for a Plugin_hook task. We don't need any
832 Plugin_hook::locks(Task_locker*)
836 // Run the "all symbols read" plugin hook.
839 Plugin_hook::run(Workqueue* workqueue)
841 gold_assert(this->options_.has_plugins());
842 this->options_.plugins()->all_symbols_read(workqueue,
844 this->input_objects_,
849 &this->this_blocker_);
850 workqueue->queue_soon(new Plugin_finish(this->this_blocker_,
851 this->next_blocker_));
854 // The C interface routines called by the plugins.
856 #ifdef ENABLE_PLUGINS
858 // Register a claim-file handler.
860 static enum ld_plugin_status
861 register_claim_file(ld_plugin_claim_file_handler handler)
863 gold_assert(parameters->options().has_plugins());
864 parameters->options().plugins()->set_claim_file_handler(handler);
868 // Register an all-symbols-read handler.
870 static enum ld_plugin_status
871 register_all_symbols_read(ld_plugin_all_symbols_read_handler handler)
873 gold_assert(parameters->options().has_plugins());
874 parameters->options().plugins()->set_all_symbols_read_handler(handler);
878 // Register a cleanup handler.
880 static enum ld_plugin_status
881 register_cleanup(ld_plugin_cleanup_handler handler)
883 gold_assert(parameters->options().has_plugins());
884 parameters->options().plugins()->set_cleanup_handler(handler);
888 // Add symbols from a plugin-claimed input file.
890 static enum ld_plugin_status
891 add_symbols(void* handle, int nsyms, const ld_plugin_symbol *syms)
893 gold_assert(parameters->options().has_plugins());
894 Pluginobj* obj = parameters->options().plugins()->make_plugin_object(
895 static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
898 obj->store_incoming_symbols(nsyms, syms);
902 // Get the input file information with an open (possibly re-opened)
905 static enum ld_plugin_status
906 get_input_file(const void *handle, struct ld_plugin_input_file *file)
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()->get_input_file(obj_index, file);
914 // Release the input file.
916 static enum ld_plugin_status
917 release_input_file(const void *handle)
919 gold_assert(parameters->options().has_plugins());
920 unsigned int obj_index =
921 static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle));
922 return parameters->options().plugins()->release_input_file(obj_index);
925 // Get the symbol resolution info for a plugin-claimed input file.
927 static enum ld_plugin_status
928 get_symbols(const void * handle, int nsyms, ld_plugin_symbol* syms)
930 gold_assert(parameters->options().has_plugins());
931 Pluginobj* obj = parameters->options().plugins()->object(
932 static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
935 return obj->get_symbol_resolution_info(nsyms, syms);
938 // Add a new (real) input file generated by a plugin.
940 static enum ld_plugin_status
941 add_input_file(char *pathname)
943 gold_assert(parameters->options().has_plugins());
944 return parameters->options().plugins()->add_input_file(pathname);
947 // Issue a diagnostic message from a plugin.
949 static enum ld_plugin_status
950 message(int level, const char * format, ...)
953 va_start(args, format);
958 parameters->errors()->info(format, args);
961 parameters->errors()->warning(format, args);
965 parameters->errors()->error(format, args);
968 parameters->errors()->fatal(format, args);
976 #endif // ENABLE_PLUGINS
978 // Allocate a Pluginobj object of the appropriate size and endianness.
981 make_sized_plugin_object(Input_file* input_file, off_t offset, off_t filesize)
984 Pluginobj* obj = NULL;
986 if (parameters->target_valid())
987 target = const_cast<Target*>(¶meters->target());
989 target = const_cast<Target*>(¶meters->default_target());
991 if (target->get_size() == 32)
993 if (target->is_big_endian())
994 #ifdef HAVE_TARGET_32_BIG
995 obj = new Sized_pluginobj<32, true>(input_file->filename(),
996 input_file, offset, filesize);
998 gold_error(_("%s: not configured to support "
999 "32-bit big-endian object"),
1000 input_file->filename().c_str());
1003 #ifdef HAVE_TARGET_32_LITTLE
1004 obj = new Sized_pluginobj<32, false>(input_file->filename(),
1005 input_file, offset, filesize);
1007 gold_error(_("%s: not configured to support "
1008 "32-bit little-endian object"),
1009 input_file->filename().c_str());
1012 else if (target->get_size() == 64)
1014 if (target->is_big_endian())
1015 #ifdef HAVE_TARGET_64_BIG
1016 obj = new Sized_pluginobj<64, true>(input_file->filename(),
1017 input_file, offset, filesize);
1019 gold_error(_("%s: not configured to support "
1020 "64-bit big-endian object"),
1021 input_file->filename().c_str());
1024 #ifdef HAVE_TARGET_64_LITTLE
1025 obj = new Sized_pluginobj<64, false>(input_file->filename(),
1026 input_file, offset, filesize);
1028 gold_error(_("%s: not configured to support "
1029 "64-bit little-endian object"),
1030 input_file->filename().c_str());
1034 gold_assert(obj != NULL);
1035 obj->set_target(target);
1039 } // End namespace gold.