1 // readsyms.cc -- read input file symbols for gold
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@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.
29 #include "dirsearch.h"
37 #include "incremental.h"
42 // If we fail to open the object, then we won't create an Add_symbols
43 // task. However, we still need to unblock the token, or else the
44 // link won't proceed to generate more error messages. We can only
45 // unblock tokens when the workqueue lock is held, so we need a dummy
46 // task to do that. The dummy task has to maintain the right sequence
47 // of blocks, so we need both this_blocker and next_blocker.
49 class Unblock_token : public Task
52 Unblock_token(Task_token* this_blocker, Task_token* next_blocker)
53 : this_blocker_(this_blocker), next_blocker_(next_blocker)
58 if (this->this_blocker_ != NULL)
59 delete this->this_blocker_;
65 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
66 return this->this_blocker_;
71 locks(Task_locker* tl)
72 { tl->add(this, this->next_blocker_); }
80 { return "Unblock_token"; }
83 Task_token* this_blocker_;
84 Task_token* next_blocker_;
87 // Class read_symbols.
89 Read_symbols::~Read_symbols()
91 // The this_blocker_ and next_blocker_ pointers are passed on to the
95 // If appropriate, issue a warning about skipping an incompatible
99 Read_symbols::incompatible_warning(const Input_argument* input_argument,
100 const Input_file* input_file)
102 if (parameters->options().warn_search_mismatch())
103 gold_warning("skipping incompatible %s while searching for %s",
104 input_file->filename().c_str(),
105 input_argument->file().name());
108 // Requeue a Read_symbols task to search for the next object with the
112 Read_symbols::requeue(Workqueue* workqueue, Input_objects* input_objects,
113 Symbol_table* symtab, Layout* layout, Dirsearch* dirpath,
114 int dirindex, Mapfile* mapfile,
115 const Input_argument* input_argument,
116 Input_group* input_group, Task_token* next_blocker)
118 // Bump the directory search index.
121 // We don't need to worry about this_blocker, since we already
122 // reached it. However, we are removing the blocker on next_blocker
123 // because the calling task is completing. So we need to add a new
124 // blocker. Since next_blocker may be shared by several tasks, we
125 // need to increment the count with the workqueue lock held.
126 workqueue->add_blocker(next_blocker);
128 workqueue->queue(new Read_symbols(input_objects, symtab, layout, dirpath,
129 dirindex, mapfile, input_argument,
130 input_group, NULL, NULL, next_blocker));
133 // Return whether a Read_symbols task is runnable. We can read an
134 // ordinary input file immediately. For an archive specified using
135 // -l, we have to wait until the search path is complete.
138 Read_symbols::is_runnable()
140 if (this->input_argument_->is_file()
141 && this->input_argument_->file().may_need_search()
142 && this->dirpath_->token()->is_blocked())
143 return this->dirpath_->token();
148 // Return a Task_locker for a Read_symbols task. We don't need any
152 Read_symbols::locks(Task_locker* tl)
154 if (this->member_ != NULL)
155 tl->add(this, this->next_blocker_);
158 // Run a Read_symbols task.
161 Read_symbols::run(Workqueue* workqueue)
163 // If we didn't queue a new task, then we need to explicitly unblock
164 // the token. If the object is a member of a lib group, however,
165 // the token was already added to the list of locks for the task,
166 // and it will be unblocked automatically at the end of the task.
167 if (!this->do_read_symbols(workqueue) && this->member_ == NULL)
168 workqueue->queue_soon(new Unblock_token(this->this_blocker_,
169 this->next_blocker_));
172 // Handle a whole lib group. Other than collecting statistics, this just
173 // mimics what we do for regular object files in the command line.
176 Read_symbols::do_whole_lib_group(Workqueue* workqueue)
178 const Input_file_lib* lib_group = this->input_argument_->lib();
180 ++Lib_group::total_lib_groups;
182 Task_token* this_blocker = this->this_blocker_;
183 for (Input_file_lib::const_iterator i = lib_group->begin();
184 i != lib_group->end();
187 ++Lib_group::total_members;
188 ++Lib_group::total_members_loaded;
190 const Input_argument* arg = &*i;
192 Task_token* next_blocker;
193 if (i != lib_group->end() - 1)
195 next_blocker = new Task_token(true);
196 next_blocker->add_blocker();
199 next_blocker = this->next_blocker_;
201 workqueue->queue_soon(new Read_symbols(this->input_objects_,
202 this->symtab_, this->layout_,
203 this->dirpath_, this->dirindex_,
204 this->mapfile_, arg, NULL,
205 NULL, this_blocker, next_blocker));
206 this_blocker = next_blocker;
212 // Handle a lib group. We set Read_symbols Tasks as usual, but have them
213 // just record the symbol data instead of adding the objects. We also start
214 // a Add_lib_group_symbols Task which runs after we've read all the symbols.
215 // In that task we process the members in a loop until we are done.
218 Read_symbols::do_lib_group(Workqueue* workqueue)
220 const Input_file_lib* lib_group = this->input_argument_->lib();
222 if (lib_group->options().whole_archive())
223 return this->do_whole_lib_group(workqueue);
225 Lib_group* lib = new Lib_group(lib_group, this);
227 Add_lib_group_symbols* add_lib_group_symbols =
228 new Add_lib_group_symbols(this->symtab_, this->layout_,
229 this->input_objects_,
230 lib, this->next_blocker_);
233 Task_token* next_blocker = new Task_token(true);
235 for (Input_file_lib::const_iterator i = lib_group->begin();
236 i != lib_group->end();
239 const Input_argument* arg = &*i;
240 Archive_member* m = lib->get_member(j);
242 next_blocker->add_blocker();
244 // Since this Read_symbols will not create an Add_symbols,
245 // just pass NULL as this_blocker.
246 workqueue->queue_soon(new Read_symbols(this->input_objects_,
247 this->symtab_, this->layout_,
248 this->dirpath_, this->dirindex_,
249 this->mapfile_, arg, NULL,
250 m, NULL, next_blocker));
253 add_lib_group_symbols->set_blocker(next_blocker, this->this_blocker_);
254 workqueue->queue_soon(add_lib_group_symbols);
259 // Open the file and read the symbols. Return true if a new task was
260 // queued, false if that could not happen due to some error.
263 Read_symbols::do_read_symbols(Workqueue* workqueue)
265 if (this->input_argument_->is_group())
267 gold_assert(this->input_group_ == NULL);
268 this->do_group(workqueue);
272 if (this->input_argument_->is_lib())
273 return this->do_lib_group(workqueue);
275 Input_file* input_file = new Input_file(&this->input_argument_->file());
276 if (!input_file->open(*this->dirpath_, this, &this->dirindex_))
279 // Read enough of the file to pick up the entire ELF header.
281 off_t filesize = input_file->file().filesize();
285 gold_error(_("%s: file is empty"),
286 input_file->file().filename().c_str());
290 const unsigned char* ehdr;
292 bool is_elf = is_elf_object(input_file, 0, &ehdr, &read_size);
294 if (read_size >= Archive::sarmag)
297 = memcmp(ehdr, Archive::armagt, Archive::sarmag) == 0;
299 || memcmp(ehdr, Archive::armag, Archive::sarmag) == 0)
301 // This is an archive.
302 Archive* arch = new Archive(this->input_argument_->file().name(),
303 input_file, is_thin_archive,
304 this->dirpath_, this);
307 // Unlock the archive so it can be used in the next task.
310 workqueue->queue_next(new Add_archive_symbols(this->symtab_,
312 this->input_objects_,
316 this->input_argument_,
320 this->next_blocker_));
325 Object* elf_obj = NULL;
327 bool* punconfigured = NULL;
330 // This is an ELF object.
332 unconfigured = false;
333 punconfigured = (input_file->will_search_for()
336 elf_obj = make_elf_object(input_file->filename(),
337 input_file, 0, ehdr, read_size,
341 if (parameters->options().has_plugins())
343 Pluginobj* obj = parameters->options().plugins()->claim_file(input_file,
348 // Delete the elf_obj, this file has been claimed.
352 // The input file was claimed by a plugin, and its symbols
353 // have been provided by the plugin.
355 // We are done with the file at this point, so unlock it.
358 if (this->member_ != NULL)
360 this->member_->sd_ = NULL;
361 this->member_->obj_ = obj;
365 workqueue->queue_next(new Add_symbols(this->input_objects_,
371 this->input_argument_,
376 this->next_blocker_));
383 // This is an ELF object.
389 Read_symbols::incompatible_warning(this->input_argument_,
391 input_file->file().release();
392 input_file->file().unlock(this);
395 return this->do_read_symbols(workqueue);
400 Read_symbols_data* sd = new Read_symbols_data;
401 elf_obj->read_symbols(sd);
403 // Opening the file locked it, so now we need to unlock it. We
404 // need to unlock it before queuing the Add_symbols task,
405 // because the workqueue doesn't know about our lock on the
406 // file. If we queue the Add_symbols task first, it will be
407 // stuck on the end of the file lock, but since the workqueue
408 // doesn't know about that lock, it will never release the
411 input_file->file().unlock(this);
413 if (this->member_ != NULL)
415 this->member_->sd_ = sd;
416 this->member_->obj_ = elf_obj;
417 this->member_->arg_serial_ =
418 this->input_argument_->file().arg_serial();
422 // We use queue_next because everything is cached for this
423 // task to run right away if possible.
425 workqueue->queue_next(new Add_symbols(this->input_objects_,
426 this->symtab_, this->layout_,
430 this->input_argument_,
435 this->next_blocker_));
440 // Queue up a task to try to parse this file as a script. We use a
441 // separate task so that the script will be read in order with other
442 // objects named on the command line. Also so that we don't try to
443 // read multiple scripts simultaneously, which could lead to
444 // unpredictable changes to the General_options structure.
446 workqueue->queue_soon(new Read_script(this->symtab_,
450 this->input_objects_,
453 this->input_argument_,
456 this->next_blocker_));
460 // Handle a group. We need to walk through the arguments over and
461 // over until we don't see any new undefined symbols. We do this by
462 // setting off Read_symbols Tasks as usual, but recording the archive
463 // entries instead of deleting them. We also start a Finish_group
464 // Task which runs after we've read all the symbols. In that task we
465 // process the archives in a loop until we are done.
468 Read_symbols::do_group(Workqueue* workqueue)
470 Input_group* input_group = new Input_group();
472 const Input_file_group* group = this->input_argument_->group();
473 Task_token* this_blocker = this->this_blocker_;
475 Finish_group* finish_group = new Finish_group(this->input_objects_,
480 this->next_blocker_);
482 Task_token* next_blocker = new Task_token(true);
483 next_blocker->add_blocker();
484 workqueue->queue_soon(new Start_group(this->symtab_, finish_group,
485 this_blocker, next_blocker));
486 this_blocker = next_blocker;
488 for (Input_file_group::const_iterator p = group->begin();
492 const Input_argument* arg = &*p;
493 gold_assert(arg->is_file());
495 next_blocker = new Task_token(true);
496 next_blocker->add_blocker();
497 workqueue->queue_soon(new Read_symbols(this->input_objects_,
498 this->symtab_, this->layout_,
499 this->dirpath_, this->dirindex_,
500 this->mapfile_, arg, input_group,
501 NULL, this_blocker, next_blocker));
502 this_blocker = next_blocker;
505 finish_group->set_blocker(this_blocker);
507 workqueue->queue_soon(finish_group);
510 // Return a debugging name for a Read_symbols task.
513 Read_symbols::get_name() const
515 if (this->input_argument_->is_group())
517 std::string ret("Read_symbols group (");
518 bool add_space = false;
519 const Input_file_group* group = this->input_argument_->group();
520 for (Input_file_group::const_iterator p = group->begin();
526 ret += p->file().name();
531 else if (this->input_argument_->is_lib())
533 std::string ret("Read_symbols lib (");
534 bool add_space = false;
535 const Input_file_lib* lib = this->input_argument_->lib();
536 for (Input_file_lib::const_iterator p = lib->begin();
542 ret += p->file().name();
549 std::string ret("Read_symbols ");
550 if (this->input_argument_->file().is_lib())
552 else if (this->input_argument_->file().is_searched_file())
554 ret += this->input_argument_->file().name();
559 // Class Add_symbols.
561 Add_symbols::~Add_symbols()
563 if (this->this_blocker_ != NULL)
564 delete this->this_blocker_;
565 // next_blocker_ is deleted by the task associated with the next
569 // We are blocked by this_blocker_. We block next_blocker_. We also
573 Add_symbols::is_runnable()
575 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
576 return this->this_blocker_;
577 if (this->object_->is_locked())
578 return this->object_->token();
583 Add_symbols::locks(Task_locker* tl)
585 tl->add(this, this->next_blocker_);
586 Task_token* token = this->object_->token();
588 tl->add(this, token);
591 // Add the symbols in the object to the symbol table.
594 Add_symbols::run(Workqueue*)
596 Pluginobj* pluginobj = this->object_->pluginobj();
597 if (pluginobj != NULL)
599 this->object_->add_symbols(this->symtab_, this->sd_, this->layout_);
603 if (!this->input_objects_->add_object(this->object_))
605 this->object_->discard_decompressed_sections();
606 gold_assert(this->sd_ != NULL);
609 this->object_->release();
610 delete this->object_;
614 Incremental_inputs* incremental_inputs =
615 this->layout_->incremental_inputs();
616 if (incremental_inputs != NULL)
618 if (this->library_ != NULL && !this->library_->is_reported())
620 Incremental_binary* ibase = this->layout_->incremental_base();
621 gold_assert(ibase != NULL);
622 unsigned int lib_serial = this->library_->arg_serial();
623 unsigned int lib_index = this->library_->input_file_index();
624 Script_info* lib_script_info = ibase->get_script_info(lib_index);
625 incremental_inputs->report_archive_begin(this->library_,
629 unsigned int arg_serial = this->input_argument_->file().arg_serial();
630 Script_info* script_info = this->input_argument_->script_info();
631 incremental_inputs->report_object(this->object_, arg_serial,
632 this->library_, script_info);
634 this->object_->layout(this->symtab_, this->layout_, this->sd_);
635 this->object_->add_symbols(this->symtab_, this->sd_, this->layout_);
636 this->object_->discard_decompressed_sections();
639 this->object_->release();
643 // Class Read_member.
645 Read_member::~Read_member()
647 if (this->this_blocker_ != NULL)
648 delete this->this_blocker_;
649 // next_blocker_ is deleted by the task associated with the next
653 // Return whether a Read_member task is runnable.
656 Read_member::is_runnable()
658 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
659 return this->this_blocker_;
664 Read_member::locks(Task_locker* tl)
666 tl->add(this, this->next_blocker_);
669 // Run a Read_member task.
672 Read_member::run(Workqueue*)
674 // This task doesn't need to do anything for now. The Read_symbols task
675 // that is queued for the archive library will cause the archive to be
676 // processed from scratch.
679 // Class Check_script.
681 Check_script::~Check_script()
683 if (this->this_blocker_ != NULL)
684 delete this->this_blocker_;
685 // next_blocker_ is deleted by the task associated with the next
689 // Return whether a Check_script task is runnable.
692 Check_script::is_runnable()
694 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
695 return this->this_blocker_;
700 Check_script::locks(Task_locker* tl)
702 tl->add(this, this->next_blocker_);
705 // Run a Check_script task.
708 Check_script::run(Workqueue*)
710 Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
711 gold_assert(incremental_inputs != NULL);
712 unsigned int arg_serial = this->input_reader_->arg_serial();
713 Script_info* script_info =
714 this->ibase_->get_script_info(this->input_file_index_);
715 Timespec mtime = this->input_reader_->get_mtime();
716 incremental_inputs->report_script(script_info, arg_serial, mtime);
719 // Class Check_library.
721 Check_library::~Check_library()
723 if (this->this_blocker_ != NULL)
724 delete this->this_blocker_;
725 // next_blocker_ is deleted by the task associated with the next
729 // Return whether a Check_library task is runnable.
732 Check_library::is_runnable()
734 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
735 return this->this_blocker_;
740 Check_library::locks(Task_locker* tl)
742 tl->add(this, this->next_blocker_);
745 // Run a Check_library task.
748 Check_library::run(Workqueue*)
750 Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
751 gold_assert(incremental_inputs != NULL);
752 Incremental_library* lib = this->ibase_->get_library(this->input_file_index_);
753 gold_assert(lib != NULL);
754 lib->copy_unused_symbols();
755 // FIXME: Check that unused symbols remain unused.
756 if (!lib->is_reported())
758 unsigned int lib_serial = lib->arg_serial();
759 unsigned int lib_index = lib->input_file_index();
760 Script_info* script_info = this->ibase_->get_script_info(lib_index);
761 incremental_inputs->report_archive_begin(lib, lib_serial, script_info);
763 incremental_inputs->report_archive_end(lib);
766 // Class Input_group.
768 // When we delete an Input_group we can delete the archive
771 Input_group::~Input_group()
773 for (Input_group::const_iterator p = this->begin();
779 // Class Start_group.
781 Start_group::~Start_group()
783 if (this->this_blocker_ != NULL)
784 delete this->this_blocker_;
785 // next_blocker_ is deleted by the task associated with the first
786 // file in the group.
789 // We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_.
792 Start_group::is_runnable()
794 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
795 return this->this_blocker_;
800 Start_group::locks(Task_locker* tl)
802 tl->add(this, this->next_blocker_);
805 // Store the number of undefined symbols we see now.
808 Start_group::run(Workqueue*)
810 this->finish_group_->set_saw_undefined(this->symtab_->saw_undefined());
813 // Class Finish_group.
815 Finish_group::~Finish_group()
817 if (this->this_blocker_ != NULL)
818 delete this->this_blocker_;
819 // next_blocker_ is deleted by the task associated with the next
820 // input file following the group.
823 // We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_.
826 Finish_group::is_runnable()
828 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
829 return this->this_blocker_;
834 Finish_group::locks(Task_locker* tl)
836 tl->add(this, this->next_blocker_);
839 // Loop over the archives until there are no new undefined symbols.
842 Finish_group::run(Workqueue*)
844 size_t saw_undefined = this->saw_undefined_;
845 while (saw_undefined != this->symtab_->saw_undefined())
847 saw_undefined = this->symtab_->saw_undefined();
849 for (Input_group::const_iterator p = this->input_group_->begin();
850 p != this->input_group_->end();
853 Task_lock_obj<Archive> tl(this, *p);
855 (*p)->add_symbols(this->symtab_, this->layout_,
856 this->input_objects_, this->mapfile_);
860 // Now that we're done with the archives, record the incremental
861 // layout information.
862 for (Input_group::const_iterator p = this->input_group_->begin();
863 p != this->input_group_->end();
866 // For an incremental link, finish recording the layout information.
867 Incremental_inputs* incremental_inputs =
868 this->layout_->incremental_inputs();
869 if (incremental_inputs != NULL)
870 incremental_inputs->report_archive_end(*p);
873 if (parameters->options().has_plugins())
874 parameters->options().plugins()->save_input_group(this->input_group_);
876 delete this->input_group_;
881 Read_script::~Read_script()
883 if (this->this_blocker_ != NULL)
884 delete this->this_blocker_;
885 // next_blocker_ is deleted by the task associated with the next
889 // We are blocked by this_blocker_.
892 Read_script::is_runnable()
894 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
895 return this->this_blocker_;
899 // We don't unlock next_blocker_ here. If the script names any input
900 // files, then the last file will be responsible for unlocking it.
903 Read_script::locks(Task_locker*)
907 // Read the script, if it is a script.
910 Read_script::run(Workqueue* workqueue)
912 bool used_next_blocker;
913 if (!read_input_script(workqueue, this->symtab_, this->layout_,
914 this->dirpath_, this->dirindex_, this->input_objects_,
915 this->mapfile_, this->input_group_,
916 this->input_argument_, this->input_file_,
917 this->next_blocker_, &used_next_blocker))
919 // Here we have to handle any other input file types we need.
920 gold_error(_("%s: not an object or archive"),
921 this->input_file_->file().filename().c_str());
924 if (!used_next_blocker)
926 // Queue up a task to unlock next_blocker. We can't just unlock
927 // it here, as we don't hold the workqueue lock.
928 workqueue->queue_soon(new Unblock_token(NULL, this->next_blocker_));
932 // Return a debugging name for a Read_script task.
935 Read_script::get_name() const
937 std::string ret("Read_script ");
938 if (this->input_argument_->file().is_lib())
940 else if (this->input_argument_->file().is_searched_file())
942 ret += this->input_argument_->file().name();
946 } // End namespace gold.