1 // readsyms.cc -- read input file symbols for gold
3 // Copyright (C) 2006-2019 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.