1 // plugin.c -- plugin manager for gold -*- C++ -*-
3 // Copyright 2008 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_symbols(const void *handle, int nsyms, struct ld_plugin_symbol *syms);
67 static enum ld_plugin_status
68 add_input_file(char *pathname);
70 static enum ld_plugin_status
71 message(int level, const char *format, ...);
75 #endif // ENABLE_PLUGINS
77 static Pluginobj* make_sized_plugin_object(Input_file* input_file,
82 // Load one plugin library.
88 // Load the plugin library.
89 // FIXME: Look for the library in standard locations.
90 this->handle_ = dlopen(this->filename_.c_str(), RTLD_NOW);
91 if (this->handle_ == NULL)
93 gold_error(_("%s: could not load plugin library"),
94 this->filename_.c_str());
98 // Find the plugin's onload entry point.
99 ld_plugin_onload onload = reinterpret_cast<ld_plugin_onload>
100 (dlsym(this->handle_, "onload"));
103 gold_error(_("%s: could not find onload entry point"),
104 this->filename_.c_str());
108 // Get the linker's version number.
109 const char* ver = get_version_string();
112 sscanf(ver, "%d.%d", &major, &minor);
114 // Allocate and populate a transfer vector.
115 const int tv_fixed_size = 11;
116 int tv_size = this->args_.size() + tv_fixed_size;
117 ld_plugin_tv *tv = new ld_plugin_tv[tv_size];
119 // Put LDPT_MESSAGE at the front of the list so the plugin can use it
120 // while processing subsequent entries.
122 tv[i].tv_tag = LDPT_MESSAGE;
123 tv[i].tv_u.tv_message = message;
126 tv[i].tv_tag = LDPT_API_VERSION;
127 tv[i].tv_u.tv_val = LD_PLUGIN_API_VERSION;
130 tv[i].tv_tag = LDPT_GOLD_VERSION;
131 tv[i].tv_u.tv_val = major * 100 + minor;
134 tv[i].tv_tag = LDPT_LINKER_OUTPUT;
135 if (parameters->options().relocatable())
136 tv[i].tv_u.tv_val = LDPO_REL;
137 else if (parameters->options().shared())
138 tv[i].tv_u.tv_val = LDPO_DYN;
140 tv[i].tv_u.tv_val = LDPO_EXEC;
142 for (unsigned int j = 0; j < this->args_.size(); ++j)
145 tv[i].tv_tag = LDPT_OPTION;
146 tv[i].tv_u.tv_string = this->args_[j].c_str();
150 tv[i].tv_tag = LDPT_REGISTER_CLAIM_FILE_HOOK;
151 tv[i].tv_u.tv_register_claim_file = register_claim_file;
154 tv[i].tv_tag = LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK;
155 tv[i].tv_u.tv_register_all_symbols_read = register_all_symbols_read;
158 tv[i].tv_tag = LDPT_REGISTER_CLEANUP_HOOK;
159 tv[i].tv_u.tv_register_cleanup = register_cleanup;
162 tv[i].tv_tag = LDPT_ADD_SYMBOLS;
163 tv[i].tv_u.tv_add_symbols = add_symbols;
166 tv[i].tv_tag = LDPT_GET_SYMBOLS;
167 tv[i].tv_u.tv_get_symbols = get_symbols;
170 tv[i].tv_tag = LDPT_ADD_INPUT_FILE;
171 tv[i].tv_u.tv_add_input_file = add_input_file;
174 tv[i].tv_tag = LDPT_NULL;
175 tv[i].tv_u.tv_val = 0;
177 gold_assert(i == tv_size - 1);
179 // Call the onload entry point.
183 #endif // ENABLE_PLUGINS
186 // Call the plugin claim-file handler.
189 Plugin::claim_file(struct ld_plugin_input_file *plugin_input_file)
193 if (this->claim_file_handler_ != NULL)
195 (*this->claim_file_handler_)(plugin_input_file, &claimed);
202 // Call the all-symbols-read handler.
205 Plugin::all_symbols_read()
207 if (this->all_symbols_read_handler_ != NULL)
208 (*this->all_symbols_read_handler_)();
211 // Call the cleanup handler.
216 if (this->cleanup_handler_ != NULL)
217 (*this->cleanup_handler_)();
220 // Plugin_manager methods.
222 Plugin_manager::~Plugin_manager()
224 for (Plugin_list::iterator p = this->plugins_.begin();
225 p != this->plugins_.end();
228 this->plugins_.clear();
229 for (Object_list::iterator obj = this->objects_.begin();
230 obj != this->objects_.end();
233 this->objects_.clear();
236 // Load all plugin libraries.
239 Plugin_manager::load_plugins()
241 for (this->current_ = this->plugins_.begin();
242 this->current_ != this->plugins_.end();
244 (*this->current_)->load();
247 // Call the plugin claim-file handlers in turn to see if any claim the file.
250 Plugin_manager::claim_file(Input_file* input_file, off_t offset,
253 if (this->in_replacement_phase_)
256 unsigned int handle = this->objects_.size();
257 this->input_file_ = input_file;
258 this->plugin_input_file_.name = input_file->filename().c_str();
259 this->plugin_input_file_.fd = input_file->file().descriptor();
260 this->plugin_input_file_.offset = offset;
261 this->plugin_input_file_.filesize = filesize;
262 this->plugin_input_file_.handle = reinterpret_cast<void*>(handle);
264 for (this->current_ = this->plugins_.begin();
265 this->current_ != this->plugins_.end();
268 if ((*this->current_)->claim_file(&this->plugin_input_file_))
270 if (this->objects_.size() > handle)
271 return this->objects_[handle];
273 // If the plugin claimed the file but did not call the
274 // add_symbols callback, we need to create the Pluginobj now.
275 Pluginobj* obj = this->make_plugin_object(handle);
283 // Call the all-symbols-read handlers.
286 Plugin_manager::all_symbols_read(Workqueue* workqueue,
287 Input_objects* input_objects,
288 Symbol_table* symtab, Layout* layout,
289 Dirsearch* dirpath, Mapfile* mapfile,
290 Task_token** last_blocker)
292 this->in_replacement_phase_ = true;
293 this->workqueue_ = workqueue;
294 this->input_objects_ = input_objects;
295 this->symtab_ = symtab;
296 this->layout_ = layout;
297 this->dirpath_ = dirpath;
298 this->mapfile_ = mapfile;
299 this->this_blocker_ = NULL;
301 for (this->current_ = this->plugins_.begin();
302 this->current_ != this->plugins_.end();
304 (*this->current_)->all_symbols_read();
306 *last_blocker = this->this_blocker_;
309 // Call the cleanup handlers.
312 Plugin_manager::cleanup()
314 for (this->current_ = this->plugins_.begin();
315 this->current_ != this->plugins_.end();
317 (*this->current_)->cleanup();
320 // Make a new Pluginobj object. This is called when the plugin calls
321 // the add_symbols API.
324 Plugin_manager::make_plugin_object(unsigned int handle)
326 // Make sure we aren't asked to make an object for the same handle twice.
327 if (this->objects_.size() != handle)
330 Pluginobj* obj = make_sized_plugin_object(this->input_file_,
331 this->plugin_input_file_.offset);
332 this->objects_.push_back(obj);
336 // Add a new input file.
339 Plugin_manager::add_input_file(char *pathname)
341 Input_file_argument file(pathname, false, "", false, this->options_);
342 Input_argument* input_argument = new Input_argument(file);
343 Task_token* next_blocker = new Task_token(true);
344 next_blocker->add_blocker();
345 this->workqueue_->queue_soon(new Read_symbols(this->options_,
346 this->input_objects_,
355 this->this_blocker_ = next_blocker;
361 Pluginobj::Pluginobj(const std::string& name, Input_file* input_file,
363 : Object(name, input_file, false, offset),
364 nsyms_(0), syms_(NULL), symbols_(), comdat_map_()
368 // Get symbol resolution info.
371 Pluginobj::get_symbol_resolution_info(int nsyms, ld_plugin_symbol* syms) const
373 if (nsyms > this->nsyms_)
375 for (int i = 0; i < nsyms; i++)
377 ld_plugin_symbol* isym = &syms[i];
378 Symbol* lsym = this->symbols_[i];
379 ld_plugin_symbol_resolution res = LDPR_UNKNOWN;
381 if (lsym->is_undefined())
382 // The symbol remains undefined.
384 else if (isym->def == LDPK_UNDEF
385 || isym->def == LDPK_WEAKUNDEF
386 || isym->def == LDPK_COMMON)
388 // The original symbol was undefined or common.
389 if (lsym->source() != Symbol::FROM_OBJECT)
390 res = LDPR_RESOLVED_EXEC;
391 else if (lsym->object()->pluginobj() != NULL)
392 res = LDPR_RESOLVED_IR;
393 else if (lsym->object()->is_dynamic())
394 res = LDPR_RESOLVED_DYN;
396 res = LDPR_RESOLVED_EXEC;
400 // The original symbol was a definition.
401 if (lsym->source() != Symbol::FROM_OBJECT)
402 res = LDPR_PREEMPTED_REG;
403 else if (lsym->object() == static_cast<const Object*>(this))
404 res = (lsym->in_real_elf()
405 ? LDPR_PREVAILING_DEF
406 : LDPR_PREVAILING_DEF_IRONLY);
408 res = (lsym->object()->pluginobj() != NULL
410 : LDPR_PREEMPTED_REG);
412 isym->resolution = res;
417 // Return TRUE if the comdat group with key COMDAT_KEY from this object
421 Pluginobj::include_comdat_group(std::string comdat_key, Layout* layout)
423 std::pair<Comdat_map::iterator, bool> ins =
424 this->comdat_map_.insert(std::make_pair(comdat_key, false));
426 // If this is the first time we've seen this comdat key, ask the
427 // layout object whether it should be included.
429 ins.first->second = layout->add_comdat(NULL, 1, comdat_key, true);
431 return ins.first->second;
434 // Class Sized_pluginobj.
436 template<int size, bool big_endian>
437 Sized_pluginobj<size, big_endian>::Sized_pluginobj(
438 const std::string& name,
439 Input_file* input_file,
441 : Pluginobj(name, input_file, offset)
445 // Read the symbols. Not used for plugin objects.
447 template<int size, bool big_endian>
449 Sized_pluginobj<size, big_endian>::do_read_symbols(Read_symbols_data*)
454 // Lay out the input sections. Not used for plugin objects.
456 template<int size, bool big_endian>
458 Sized_pluginobj<size, big_endian>::do_layout(Symbol_table*, Layout*,
464 // Add the symbols to the symbol table.
466 template<int size, bool big_endian>
468 Sized_pluginobj<size, big_endian>::do_add_symbols(Symbol_table*,
474 template<int size, bool big_endian>
476 Sized_pluginobj<size, big_endian>::do_add_symbols(Symbol_table* symtab,
479 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
480 unsigned char symbuf[sym_size];
481 elfcpp::Sym<size, big_endian> sym(symbuf);
482 elfcpp::Sym_write<size, big_endian> osym(symbuf);
484 typedef typename elfcpp::Elf_types<size>::Elf_WXword Elf_size_type;
486 this->symbols_.resize(this->nsyms_);
488 for (int i = 0; i < this->nsyms_; ++i)
490 const struct ld_plugin_symbol *isym = &this->syms_[i];
491 const char* name = isym->name;
492 const char* ver = isym->version;
493 elfcpp::Elf_Half shndx;
497 if (name != NULL && name[0] == '\0')
499 if (ver != NULL && ver[0] == '\0')
506 bind = elfcpp::STB_WEAK;
512 bind = elfcpp::STB_GLOBAL;
520 shndx = elfcpp::SHN_ABS;
523 shndx = elfcpp::SHN_COMMON;
528 shndx = elfcpp::SHN_UNDEF;
532 switch (isym->visibility)
535 vis = elfcpp::STV_DEFAULT;
538 vis = elfcpp::STV_DEFAULT;
541 vis = elfcpp::STV_DEFAULT;
545 vis = elfcpp::STV_DEFAULT;
549 if (isym->comdat_key != NULL
550 && isym->comdat_key[0] != '\0'
551 && !this->include_comdat_group(isym->comdat_key, layout))
552 shndx = elfcpp::SHN_UNDEF;
555 osym.put_st_value(0);
556 osym.put_st_size(static_cast<Elf_size_type>(isym->size));
557 osym.put_st_info(bind, elfcpp::STT_NOTYPE);
558 osym.put_st_other(vis, 0);
559 osym.put_st_shndx(shndx);
562 symtab->add_from_pluginobj<size, big_endian>(this, name, ver, &sym);
566 // Get the size of a section. Not used for plugin objects.
568 template<int size, bool big_endian>
570 Sized_pluginobj<size, big_endian>::do_section_size(unsigned int)
576 // Get the name of a section. Not used for plugin objects.
578 template<int size, bool big_endian>
580 Sized_pluginobj<size, big_endian>::do_section_name(unsigned int)
583 return std::string();
586 // Return a view of the contents of a section. Not used for plugin objects.
588 template<int size, bool big_endian>
590 Sized_pluginobj<size, big_endian>::do_section_contents(unsigned int)
598 // Return section flags. Not used for plugin objects.
600 template<int size, bool big_endian>
602 Sized_pluginobj<size, big_endian>::do_section_flags(unsigned int)
608 // Return section address. Not used for plugin objects.
610 template<int size, bool big_endian>
612 Sized_pluginobj<size, big_endian>::do_section_address(unsigned int)
618 // Return section type. Not used for plugin objects.
620 template<int size, bool big_endian>
622 Sized_pluginobj<size, big_endian>::do_section_type(unsigned int)
628 // Return the section link field. Not used for plugin objects.
630 template<int size, bool big_endian>
632 Sized_pluginobj<size, big_endian>::do_section_link(unsigned int)
638 // Return the section link field. Not used for plugin objects.
640 template<int size, bool big_endian>
642 Sized_pluginobj<size, big_endian>::do_section_info(unsigned int)
648 // Return the section alignment. Not used for plugin objects.
650 template<int size, bool big_endian>
652 Sized_pluginobj<size, big_endian>::do_section_addralign(unsigned int)
658 // Return the Xindex structure to use. Not used for plugin objects.
660 template<int size, bool big_endian>
662 Sized_pluginobj<size, big_endian>::do_initialize_xindex()
668 // Get symbol counts. Not used for plugin objects.
670 template<int size, bool big_endian>
672 Sized_pluginobj<size, big_endian>::do_get_global_symbol_counts(const Symbol_table*,
673 size_t*, size_t*) const
678 // Class Add_plugin_symbols.
680 Add_plugin_symbols::~Add_plugin_symbols()
682 if (this->this_blocker_ != NULL)
683 delete this->this_blocker_;
684 // next_blocker_ is deleted by the task associated with the next
688 // We are blocked by this_blocker_. We block next_blocker_. We also
692 Add_plugin_symbols::is_runnable()
694 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
695 return this->this_blocker_;
696 if (this->obj_->is_locked())
697 return this->obj_->token();
702 Add_plugin_symbols::locks(Task_locker* tl)
704 tl->add(this, this->next_blocker_);
705 tl->add(this, this->obj_->token());
708 // Add the symbols in the object to the symbol table.
711 Add_plugin_symbols::run(Workqueue*)
713 this->obj_->add_symbols(this->symtab_, this->layout_);
716 // Class Plugin_cleanup. This task calls the plugin cleanup hooks once all
717 // replacement files have been added.
719 class Plugin_cleanup : public Task
722 Plugin_cleanup(Task_token* this_blocker, Task_token* next_blocker)
723 : this_blocker_(this_blocker), next_blocker_(next_blocker)
728 if (this->this_blocker_ != NULL)
729 delete this->this_blocker_;
735 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
736 return this->this_blocker_;
741 locks(Task_locker* tl)
742 { tl->add(this, this->next_blocker_); }
746 { parameters->options().plugins()->cleanup(); }
750 { return "Plugin_cleanup"; }
753 Task_token* this_blocker_;
754 Task_token* next_blocker_;
757 // Class Plugin_hook.
759 Plugin_hook::~Plugin_hook()
763 // Return whether a Plugin_hook task is runnable.
766 Plugin_hook::is_runnable()
768 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
769 return this->this_blocker_;
773 // Return a Task_locker for a Plugin_hook task. We don't need any
777 Plugin_hook::locks(Task_locker*)
781 // Run a Plugin_hook task.
784 Plugin_hook::run(Workqueue* workqueue)
786 this->do_plugin_hook(workqueue);
789 // Run the "all symbols read" plugin hook.
792 Plugin_hook::do_plugin_hook(Workqueue* workqueue)
794 gold_assert(this->options_.has_plugins());
795 this->options_.plugins()->all_symbols_read(workqueue,
796 this->input_objects_,
801 &this->this_blocker_);
802 workqueue->queue_soon(new Plugin_cleanup(this->this_blocker_,
803 this->next_blocker_));
806 // The C interface routines called by the plugins.
808 #ifdef ENABLE_PLUGINS
810 // Register a claim-file handler.
812 static enum ld_plugin_status
813 register_claim_file(ld_plugin_claim_file_handler handler)
815 gold_assert(parameters->options().has_plugins());
816 parameters->options().plugins()->set_claim_file_handler(handler);
820 // Register an all-symbols-read handler.
822 static enum ld_plugin_status
823 register_all_symbols_read(ld_plugin_all_symbols_read_handler handler)
825 gold_assert(parameters->options().has_plugins());
826 parameters->options().plugins()->set_all_symbols_read_handler(handler);
830 // Register a cleanup handler.
832 static enum ld_plugin_status
833 register_cleanup(ld_plugin_cleanup_handler handler)
835 gold_assert(parameters->options().has_plugins());
836 parameters->options().plugins()->set_cleanup_handler(handler);
840 // Add symbols from a plugin-claimed input file.
842 static enum ld_plugin_status
843 add_symbols(void* handle, int nsyms, const ld_plugin_symbol *syms)
845 gold_assert(parameters->options().has_plugins());
846 Pluginobj* obj = parameters->options().plugins()->make_plugin_object(
847 static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
850 obj->store_incoming_symbols(nsyms, syms);
854 // Get the symbol resolution info for a plugin-claimed input file.
856 static enum ld_plugin_status
857 get_symbols(const void * handle, int nsyms, ld_plugin_symbol* syms)
859 gold_assert(parameters->options().has_plugins());
860 Pluginobj* obj = parameters->options().plugins()->object(
861 static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
864 return obj->get_symbol_resolution_info(nsyms, syms);
867 // Add a new (real) input file generated by a plugin.
869 static enum ld_plugin_status
870 add_input_file(char *pathname)
872 gold_assert(parameters->options().has_plugins());
873 return parameters->options().plugins()->add_input_file(pathname);
876 // Issue a diagnostic message from a plugin.
878 static enum ld_plugin_status
879 message(int level, const char * format, ...)
882 va_start(args, format);
887 parameters->errors()->info(format, args);
890 parameters->errors()->warning(format, args);
894 parameters->errors()->error(format, args);
897 parameters->errors()->fatal(format, args);
905 #endif // ENABLE_PLUGINS
907 // Allocate a Pluginobj object of the appropriate size and endianness.
910 make_sized_plugin_object(Input_file* input_file, off_t offset)
913 Pluginobj* obj = NULL;
915 if (parameters->target_valid())
916 target = const_cast<Target*>(¶meters->target());
918 target = const_cast<Target*>(¶meters->default_target());
920 if (target->get_size() == 32)
922 if (target->is_big_endian())
923 #ifdef HAVE_TARGET_32_BIG
924 obj = new Sized_pluginobj<32, true>(input_file->filename(),
927 gold_error(_("%s: not configured to support "
928 "32-bit big-endian object"),
929 input_file->filename().c_str());
932 #ifdef HAVE_TARGET_32_LITTLE
933 obj = new Sized_pluginobj<32, false>(input_file->filename(),
936 gold_error(_("%s: not configured to support "
937 "32-bit little-endian object"),
938 input_file->filename().c_str());
941 else if (target->get_size() == 64)
943 if (target->is_big_endian())
944 #ifdef HAVE_TARGET_64_BIG
945 obj = new Sized_pluginobj<64, true>(input_file->filename(),
948 gold_error(_("%s: not configured to support "
949 "64-bit big-endian object"),
950 input_file->filename().c_str());
953 #ifdef HAVE_TARGET_64_LITTLE
954 obj = new Sized_pluginobj<64, false>(input_file->filename(),
957 gold_error(_("%s: not configured to support "
958 "64-bit little-endian object"),
959 input_file->filename().c_str());
963 gold_assert(obj != NULL);
964 obj->set_target(target);
968 } // End namespace gold.