1 // readsyms.cc -- read input file symbols for gold
3 // Copyright 2006, 2007, 2008, 2009, 2010 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
165 if (!this->do_read_symbols(workqueue))
166 workqueue->queue_soon(new Unblock_token(this->this_blocker_,
167 this->next_blocker_));
170 // Handle a whole lib group. Other then collecting statisticts, this just
171 // mimics what we do for regular object files in the command line.
174 Read_symbols::do_whole_lib_group(Workqueue* workqueue)
176 const Input_file_lib* lib_group = this->input_argument_->lib();
178 ++Lib_group::total_lib_groups;
180 Task_token* this_blocker = this->this_blocker_;
181 for (Input_file_lib::const_iterator i = lib_group->begin();
182 i != lib_group->end();
185 ++Lib_group::total_members;
186 ++Lib_group::total_members_loaded;
188 const Input_argument* arg = &*i;
190 Task_token* next_blocker;
191 if (i != lib_group->end() - 1)
193 next_blocker = new Task_token(true);
194 next_blocker->add_blocker();
197 next_blocker = this->next_blocker_;
199 workqueue->queue_soon(new Read_symbols(this->input_objects_,
200 this->symtab_, this->layout_,
201 this->dirpath_, this->dirindex_,
202 this->mapfile_, arg, NULL,
203 NULL, this_blocker, next_blocker));
204 this_blocker = next_blocker;
210 // Handle a lib group. We set Read_symbols Tasks as usual, but have them
211 // just record the symbol data instead of adding the objects. We also start
212 // a Add_lib_group_symbols Task which runs after we've read all the symbols.
213 // In that task we process the members in a loop until we are done.
216 Read_symbols::do_lib_group(Workqueue* workqueue)
218 const Input_file_lib* lib_group = this->input_argument_->lib();
220 if (lib_group->options().whole_archive())
221 return this->do_whole_lib_group(workqueue);
223 Lib_group* lib = new Lib_group(lib_group, this);
225 Add_lib_group_symbols* add_lib_group_symbols =
226 new Add_lib_group_symbols(this->symtab_, this->layout_,
227 this->input_objects_,
228 lib, this->next_blocker_);
231 Task_token* next_blocker = new Task_token(true);
233 for (Input_file_lib::const_iterator i = lib_group->begin();
234 i != lib_group->end();
237 const Input_argument* arg = &*i;
238 Archive_member* m = lib->get_member(j);
240 next_blocker->add_blocker();
242 // Since this Read_symbols will not create an Add_symbols,
243 // just pass NULL as this_blocker.
244 workqueue->queue_soon(new Read_symbols(this->input_objects_,
245 this->symtab_, this->layout_,
246 this->dirpath_, this->dirindex_,
247 this->mapfile_, arg, NULL,
248 m, NULL, next_blocker));
251 add_lib_group_symbols->set_blocker(next_blocker);
252 workqueue->queue_soon(add_lib_group_symbols);
257 // Open the file and read the symbols. Return true if a new task was
258 // queued, false if that could not happen due to some error.
261 Read_symbols::do_read_symbols(Workqueue* workqueue)
263 if (this->input_argument_->is_group())
265 gold_assert(this->input_group_ == NULL);
266 this->do_group(workqueue);
270 if (this->input_argument_->is_lib())
271 return this->do_lib_group(workqueue);
273 Input_file* input_file = new Input_file(&this->input_argument_->file());
274 if (!input_file->open(*this->dirpath_, this, &this->dirindex_))
277 // Read enough of the file to pick up the entire ELF header.
279 off_t filesize = input_file->file().filesize();
283 gold_error(_("%s: file is empty"),
284 input_file->file().filename().c_str());
288 const unsigned char* ehdr;
290 bool is_elf = is_elf_object(input_file, 0, &ehdr, &read_size);
292 if (read_size >= Archive::sarmag)
295 = memcmp(ehdr, Archive::armagt, Archive::sarmag) == 0;
297 || memcmp(ehdr, Archive::armag, Archive::sarmag) == 0)
299 // This is an archive.
300 Archive* arch = new Archive(this->input_argument_->file().name(),
301 input_file, is_thin_archive,
302 this->dirpath_, this);
305 // Unlock the archive so it can be used in the next task.
308 workqueue->queue_next(new Add_archive_symbols(this->symtab_,
310 this->input_objects_,
314 this->input_argument_,
318 this->next_blocker_));
323 if (parameters->options().has_plugins())
325 Pluginobj* obj = parameters->options().plugins()->claim_file(input_file,
329 // The input file was claimed by a plugin, and its symbols
330 // have been provided by the plugin.
332 // We are done with the file at this point, so unlock it.
335 if (this->member_ != NULL)
337 this->member_->sd_ = NULL;
338 this->member_->obj_ = obj;
342 workqueue->queue_next(new Add_symbols(this->input_objects_,
348 this->input_argument_,
352 this->next_blocker_));
359 // This is an ELF object.
361 bool unconfigured = false;
362 bool* punconfigured = (input_file->will_search_for()
365 Object* obj = make_elf_object(input_file->filename(),
366 input_file, 0, ehdr, read_size,
372 Read_symbols::incompatible_warning(this->input_argument_,
374 input_file->file().release();
375 input_file->file().unlock(this);
378 return this->do_read_symbols(workqueue);
383 Read_symbols_data* sd = new Read_symbols_data;
384 obj->read_symbols(sd);
386 // Opening the file locked it, so now we need to unlock it. We
387 // need to unlock it before queuing the Add_symbols task,
388 // because the workqueue doesn't know about our lock on the
389 // file. If we queue the Add_symbols task first, it will be
390 // stuck on the end of the file lock, but since the workqueue
391 // doesn't know about that lock, it will never release the
394 input_file->file().unlock(this);
396 if (this->member_ != NULL)
398 this->member_->sd_ = sd;
399 this->member_->obj_ = obj;
403 // We use queue_next because everything is cached for this
404 // task to run right away if possible.
406 workqueue->queue_next(new Add_symbols(this->input_objects_,
407 this->symtab_, this->layout_,
411 this->input_argument_,
415 this->next_blocker_));
420 // Queue up a task to try to parse this file as a script. We use a
421 // separate task so that the script will be read in order with other
422 // objects named on the command line. Also so that we don't try to
423 // read multiple scripts simultaneously, which could lead to
424 // unpredictable changes to the General_options structure.
426 workqueue->queue_soon(new Read_script(this->symtab_,
430 this->input_objects_,
433 this->input_argument_,
436 this->next_blocker_));
440 // Handle a group. We need to walk through the arguments over and
441 // over until we don't see any new undefined symbols. We do this by
442 // setting off Read_symbols Tasks as usual, but recording the archive
443 // entries instead of deleting them. We also start a Finish_group
444 // Task which runs after we've read all the symbols. In that task we
445 // process the archives in a loop until we are done.
448 Read_symbols::do_group(Workqueue* workqueue)
450 Input_group* input_group = new Input_group();
452 const Input_file_group* group = this->input_argument_->group();
453 Task_token* this_blocker = this->this_blocker_;
455 Finish_group* finish_group = new Finish_group(this->input_objects_,
460 this->next_blocker_);
462 Task_token* next_blocker = new Task_token(true);
463 next_blocker->add_blocker();
464 workqueue->queue_soon(new Start_group(this->symtab_, finish_group,
465 this_blocker, next_blocker));
466 this_blocker = next_blocker;
468 for (Input_file_group::const_iterator p = group->begin();
472 const Input_argument* arg = &*p;
473 gold_assert(arg->is_file());
475 next_blocker = new Task_token(true);
476 next_blocker->add_blocker();
477 workqueue->queue_soon(new Read_symbols(this->input_objects_,
478 this->symtab_, this->layout_,
479 this->dirpath_, this->dirindex_,
480 this->mapfile_, arg, input_group,
481 NULL, this_blocker, next_blocker));
482 this_blocker = next_blocker;
485 finish_group->set_blocker(this_blocker);
487 workqueue->queue_soon(finish_group);
490 // Return a debugging name for a Read_symbols task.
493 Read_symbols::get_name() const
495 if (this->input_argument_->is_group())
497 std::string ret("Read_symbols group (");
498 bool add_space = false;
499 const Input_file_group* group = this->input_argument_->group();
500 for (Input_file_group::const_iterator p = group->begin();
506 ret += p->file().name();
511 else if (this->input_argument_->is_lib())
513 std::string ret("Read_symbols lib (");
514 bool add_space = false;
515 const Input_file_lib* lib = this->input_argument_->lib();
516 for (Input_file_lib::const_iterator p = lib->begin();
522 ret += p->file().name();
529 std::string ret("Read_symbols ");
530 if (this->input_argument_->file().is_lib())
532 else if (this->input_argument_->file().is_searched_file())
534 ret += this->input_argument_->file().name();
539 // Class Add_symbols.
541 Add_symbols::~Add_symbols()
543 if (this->this_blocker_ != NULL)
544 delete this->this_blocker_;
545 // next_blocker_ is deleted by the task associated with the next
549 // We are blocked by this_blocker_. We block next_blocker_. We also
553 Add_symbols::is_runnable()
555 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
556 return this->this_blocker_;
557 if (this->object_->is_locked())
558 return this->object_->token();
563 Add_symbols::locks(Task_locker* tl)
565 tl->add(this, this->next_blocker_);
566 tl->add(this, this->object_->token());
569 // Add the symbols in the object to the symbol table.
572 Add_symbols::run(Workqueue*)
574 Pluginobj* pluginobj = this->object_->pluginobj();
575 if (pluginobj != NULL)
577 this->object_->add_symbols(this->symtab_, this->sd_, this->layout_);
581 if (!this->input_objects_->add_object(this->object_))
585 this->object_->release();
586 delete this->object_;
590 Incremental_inputs* incremental_inputs =
591 this->layout_->incremental_inputs();
592 if (incremental_inputs != NULL)
593 incremental_inputs->report_object(this->object_, NULL);
594 this->object_->layout(this->symtab_, this->layout_, this->sd_);
595 this->object_->add_symbols(this->symtab_, this->sd_, this->layout_);
598 this->object_->release();
602 // Class Start_group.
604 Start_group::~Start_group()
606 if (this->this_blocker_ != NULL)
607 delete this->this_blocker_;
608 // next_blocker_ is deleted by the task associated with the first
609 // file in the group.
612 // We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_.
615 Start_group::is_runnable()
617 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
618 return this->this_blocker_;
623 Start_group::locks(Task_locker* tl)
625 tl->add(this, this->next_blocker_);
628 // Store the number of undefined symbols we see now.
631 Start_group::run(Workqueue*)
633 this->finish_group_->set_saw_undefined(this->symtab_->saw_undefined());
636 // Class Finish_group.
638 Finish_group::~Finish_group()
640 if (this->this_blocker_ != NULL)
641 delete this->this_blocker_;
642 // next_blocker_ is deleted by the task associated with the next
643 // input file following the group.
646 // We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_.
649 Finish_group::is_runnable()
651 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
652 return this->this_blocker_;
657 Finish_group::locks(Task_locker* tl)
659 tl->add(this, this->next_blocker_);
662 // Loop over the archives until there are no new undefined symbols.
665 Finish_group::run(Workqueue*)
667 size_t saw_undefined = this->saw_undefined_;
668 while (saw_undefined != this->symtab_->saw_undefined())
670 saw_undefined = this->symtab_->saw_undefined();
672 for (Input_group::const_iterator p = this->input_group_->begin();
673 p != this->input_group_->end();
676 Task_lock_obj<Archive> tl(this, *p);
678 (*p)->add_symbols(this->symtab_, this->layout_,
679 this->input_objects_, this->mapfile_);
683 // Now that we're done with the archives, record the incremental layout
684 // information, then delete them.
685 for (Input_group::const_iterator p = this->input_group_->begin();
686 p != this->input_group_->end();
689 // For an incremental link, finish recording the layout information.
690 Incremental_inputs* incremental_inputs =
691 this->layout_->incremental_inputs();
692 if (incremental_inputs != NULL)
693 incremental_inputs->report_archive_end(*p);
697 delete this->input_group_;
702 Read_script::~Read_script()
704 if (this->this_blocker_ != NULL)
705 delete this->this_blocker_;
706 // next_blocker_ is deleted by the task associated with the next
710 // We are blocked by this_blocker_.
713 Read_script::is_runnable()
715 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
716 return this->this_blocker_;
720 // We don't unlock next_blocker_ here. If the script names any input
721 // files, then the last file will be responsible for unlocking it.
724 Read_script::locks(Task_locker*)
728 // Read the script, if it is a script.
731 Read_script::run(Workqueue* workqueue)
733 bool used_next_blocker;
734 if (!read_input_script(workqueue, this->symtab_, this->layout_,
735 this->dirpath_, this->dirindex_, this->input_objects_,
736 this->mapfile_, this->input_group_,
737 this->input_argument_, this->input_file_,
738 this->next_blocker_, &used_next_blocker))
740 // Here we have to handle any other input file types we need.
741 gold_error(_("%s: not an object or archive"),
742 this->input_file_->file().filename().c_str());
745 if (!used_next_blocker)
747 // Queue up a task to unlock next_blocker. We can't just unlock
748 // it here, as we don't hold the workqueue lock.
749 workqueue->queue_soon(new Unblock_token(NULL, this->next_blocker_));
753 // Return a debugging name for a Read_script task.
756 Read_script::get_name() const
758 std::string ret("Read_script ");
759 if (this->input_argument_->file().is_lib())
761 else if (this->input_argument_->file().is_searched_file())
763 ret += this->input_argument_->file().name();
767 } // End namespace gold.