1 // readsyms.cc -- read input file symbols for gold
3 // Copyright 2006, 2007, 2008, 2009 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"
40 // If we fail to open the object, then we won't create an Add_symbols
41 // task. However, we still need to unblock the token, or else the
42 // link won't proceed to generate more error messages. We can only
43 // unblock tokens when the workqueue lock is held, so we need a dummy
44 // task to do that. The dummy task has to maintain the right sequence
45 // of blocks, so we need both this_blocker and next_blocker.
47 class Unblock_token : public Task
50 Unblock_token(Task_token* this_blocker, Task_token* next_blocker)
51 : this_blocker_(this_blocker), next_blocker_(next_blocker)
56 if (this->this_blocker_ != NULL)
57 delete this->this_blocker_;
63 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
64 return this->this_blocker_;
69 locks(Task_locker* tl)
70 { tl->add(this, this->next_blocker_); }
78 { return "Unblock_token"; }
81 Task_token* this_blocker_;
82 Task_token* next_blocker_;
85 // Class read_symbols.
87 Read_symbols::~Read_symbols()
89 // The this_blocker_ and next_blocker_ pointers are passed on to the
93 // If appropriate, issue a warning about skipping an incompatible
97 Read_symbols::incompatible_warning(const Input_argument* input_argument,
98 const Input_file* input_file)
100 if (parameters->options().warn_search_mismatch())
101 gold_warning("skipping incompatible %s while searching for %s",
102 input_file->filename().c_str(),
103 input_argument->file().name());
106 // Requeue a Read_symbols task to search for the next object with the
110 Read_symbols::requeue(Workqueue* workqueue, Input_objects* input_objects,
111 Symbol_table* symtab, Layout* layout, Dirsearch* dirpath,
112 int dirindex, Mapfile* mapfile,
113 const Input_argument* input_argument,
114 Input_group* input_group, Task_token* next_blocker)
116 // Bump the directory search index.
119 // We don't need to worry about this_blocker, since we already
120 // reached it. However, we are removing the blocker on next_blocker
121 // because the calling task is completing. So we need to add a new
122 // blocker. Since next_blocker may be shared by several tasks, we
123 // need to increment the count with the workqueue lock held.
124 workqueue->add_blocker(next_blocker);
126 workqueue->queue(new Read_symbols(input_objects, symtab, layout, dirpath,
127 dirindex, mapfile, input_argument,
128 input_group, NULL, next_blocker));
131 // Return whether a Read_symbols task is runnable. We can read an
132 // ordinary input file immediately. For an archive specified using
133 // -l, we have to wait until the search path is complete.
136 Read_symbols::is_runnable()
138 if (this->input_argument_->is_file()
139 && this->input_argument_->file().may_need_search()
140 && this->dirpath_->token()->is_blocked())
141 return this->dirpath_->token();
146 // Return a Task_locker for a Read_symbols task. We don't need any
150 Read_symbols::locks(Task_locker*)
154 // Run a Read_symbols task.
157 Read_symbols::run(Workqueue* workqueue)
159 // If we didn't queue a new task, then we need to explicitly unblock
161 if (!this->do_read_symbols(workqueue))
162 workqueue->queue_soon(new Unblock_token(this->this_blocker_,
163 this->next_blocker_));
166 // Open the file and read the symbols. Return true if a new task was
167 // queued, false if that could not happen due to some error.
170 Read_symbols::do_read_symbols(Workqueue* workqueue)
172 if (this->input_argument_->is_group())
174 gold_assert(this->input_group_ == NULL);
175 this->do_group(workqueue);
179 Input_file* input_file = new Input_file(&this->input_argument_->file());
180 if (!input_file->open(*this->dirpath_, this, &this->dirindex_))
183 // Read enough of the file to pick up the entire ELF header.
185 off_t filesize = input_file->file().filesize();
189 gold_error(_("%s: file is empty"),
190 input_file->file().filename().c_str());
194 const unsigned char* ehdr;
196 bool is_elf = is_elf_object(input_file, 0, &ehdr, &read_size);
198 if (read_size >= Archive::sarmag)
201 = memcmp(ehdr, Archive::armagt, Archive::sarmag) == 0;
203 || memcmp(ehdr, Archive::armag, Archive::sarmag) == 0)
205 // This is an archive.
206 Archive* arch = new Archive(this->input_argument_->file().name(),
207 input_file, is_thin_archive,
208 this->dirpath_, this);
211 // Unlock the archive so it can be used in the next task.
214 workqueue->queue_next(new Add_archive_symbols(this->symtab_,
216 this->input_objects_,
220 this->input_argument_,
224 this->next_blocker_));
229 if (parameters->options().has_plugins())
231 Pluginobj* obj = parameters->options().plugins()->claim_file(input_file,
235 // The input file was claimed by a plugin, and its symbols
236 // have been provided by the plugin.
238 // We are done with the file at this point, so unlock it.
241 workqueue->queue_next(new Add_symbols(this->input_objects_,
247 this->input_argument_,
252 this->next_blocker_));
259 // This is an ELF object.
262 Object* obj = make_elf_object(input_file->filename(),
263 input_file, 0, ehdr, read_size,
267 if (unconfigured && input_file->will_search_for())
269 Read_symbols::incompatible_warning(this->input_argument_,
271 input_file->file().release();
272 input_file->file().unlock(this);
275 return this->do_read_symbols(workqueue);
280 Read_symbols_data* sd = new Read_symbols_data;
281 obj->read_symbols(sd);
283 // Opening the file locked it, so now we need to unlock it. We
284 // need to unlock it before queuing the Add_symbols task,
285 // because the workqueue doesn't know about our lock on the
286 // file. If we queue the Add_symbols task first, it will be
287 // stuck on the end of the file lock, but since the workqueue
288 // doesn't know about that lock, it will never release the
291 input_file->file().unlock(this);
293 // We use queue_next because everything is cached for this
294 // task to run right away if possible.
296 workqueue->queue_next(new Add_symbols(this->input_objects_,
297 this->symtab_, this->layout_,
301 this->input_argument_,
306 this->next_blocker_));
311 // Queue up a task to try to parse this file as a script. We use a
312 // separate task so that the script will be read in order with other
313 // objects named on the command line. Also so that we don't try to
314 // read multiple scripts simultaneously, which could lead to
315 // unpredictable changes to the General_options structure.
317 workqueue->queue_soon(new Read_script(this->symtab_,
321 this->input_objects_,
324 this->input_argument_,
327 this->next_blocker_));
331 // Handle a group. We need to walk through the arguments over and
332 // over until we don't see any new undefined symbols. We do this by
333 // setting off Read_symbols Tasks as usual, but recording the archive
334 // entries instead of deleting them. We also start a Finish_group
335 // Task which runs after we've read all the symbols. In that task we
336 // process the archives in a loop until we are done.
339 Read_symbols::do_group(Workqueue* workqueue)
341 Input_group* input_group = new Input_group();
343 const Input_file_group* group = this->input_argument_->group();
344 Task_token* this_blocker = this->this_blocker_;
346 for (Input_file_group::const_iterator p = group->begin();
350 const Input_argument* arg = &*p;
351 gold_assert(arg->is_file());
353 Task_token* next_blocker = new Task_token(true);
354 next_blocker->add_blocker();
355 workqueue->queue_soon(new Read_symbols(this->input_objects_,
356 this->symtab_, this->layout_,
357 this->dirpath_, this->dirindex_,
358 this->mapfile_, arg, input_group,
359 this_blocker, next_blocker));
360 this_blocker = next_blocker;
363 const int saw_undefined = this->symtab_->saw_undefined();
364 workqueue->queue_soon(new Finish_group(this->input_objects_,
371 this->next_blocker_));
374 // Return a debugging name for a Read_symbols task.
377 Read_symbols::get_name() const
379 if (!this->input_argument_->is_group())
381 std::string ret("Read_symbols ");
382 if (this->input_argument_->file().is_lib())
384 ret += this->input_argument_->file().name();
388 std::string ret("Read_symbols group (");
389 bool add_space = false;
390 const Input_file_group* group = this->input_argument_->group();
391 for (Input_file_group::const_iterator p = group->begin();
397 ret += p->file().name();
403 // Class Add_symbols.
405 Add_symbols::~Add_symbols()
407 if (this->this_blocker_ != NULL)
408 delete this->this_blocker_;
409 // next_blocker_ is deleted by the task associated with the next
413 // We are blocked by this_blocker_. We block next_blocker_. We also
417 Add_symbols::is_runnable()
419 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
420 return this->this_blocker_;
421 if (this->object_->is_locked())
422 return this->object_->token();
427 Add_symbols::locks(Task_locker* tl)
429 tl->add(this, this->next_blocker_);
430 tl->add(this, this->object_->token());
433 // Add the symbols in the object to the symbol table.
436 Add_symbols::run(Workqueue* workqueue)
438 Pluginobj* pluginobj = this->object_->pluginobj();
439 if (pluginobj != NULL)
441 this->object_->add_symbols(this->symtab_, this->sd_, this->layout_);
445 // If this file has an incompatible format, try for another file
446 // with the same name.
447 if (this->object_->searched_for()
448 && !parameters->is_compatible_target(this->object_->target()))
450 Read_symbols::incompatible_warning(this->input_argument_,
451 this->object_->input_file());
452 Read_symbols::requeue(workqueue, this->input_objects_, this->symtab_,
453 this->layout_, this->dirpath_, this->dirindex_,
454 this->mapfile_, this->input_argument_,
455 this->input_group_, this->next_blocker_);
456 this->object_->release();
457 delete this->object_;
459 else if (!this->input_objects_->add_object(this->object_))
461 this->object_->release();
462 delete this->object_;
466 this->object_->layout(this->symtab_, this->layout_, this->sd_);
467 this->object_->add_symbols(this->symtab_, this->sd_, this->layout_);
468 this->object_->release();
474 // Class Finish_group.
476 Finish_group::~Finish_group()
478 if (this->this_blocker_ != NULL)
479 delete this->this_blocker_;
480 // next_blocker_ is deleted by the task associated with the next
481 // input file following the group.
484 // We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_.
487 Finish_group::is_runnable()
489 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
490 return this->this_blocker_;
495 Finish_group::locks(Task_locker* tl)
497 tl->add(this, this->next_blocker_);
500 // Loop over the archives until there are no new undefined symbols.
503 Finish_group::run(Workqueue*)
505 int saw_undefined = this->saw_undefined_;
506 while (saw_undefined != this->symtab_->saw_undefined())
508 saw_undefined = this->symtab_->saw_undefined();
510 for (Input_group::const_iterator p = this->input_group_->begin();
511 p != this->input_group_->end();
514 Task_lock_obj<Archive> tl(this, *p);
516 (*p)->add_symbols(this->symtab_, this->layout_,
517 this->input_objects_, this->mapfile_);
521 // Delete all the archives now that we no longer need them.
522 for (Input_group::const_iterator p = this->input_group_->begin();
523 p != this->input_group_->end();
526 delete this->input_group_;
531 Read_script::~Read_script()
533 if (this->this_blocker_ != NULL)
534 delete this->this_blocker_;
535 // next_blocker_ is deleted by the task associated with the next
539 // We are blocked by this_blocker_.
542 Read_script::is_runnable()
544 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
545 return this->this_blocker_;
549 // We don't unlock next_blocker_ here. If the script names any input
550 // files, then the last file will be responsible for unlocking it.
553 Read_script::locks(Task_locker*)
557 // Read the script, if it is a script.
560 Read_script::run(Workqueue* workqueue)
562 bool used_next_blocker;
563 if (!read_input_script(workqueue, this->symtab_, this->layout_,
564 this->dirpath_, this->dirindex_, this->input_objects_,
565 this->mapfile_, this->input_group_,
566 this->input_argument_, this->input_file_,
567 this->next_blocker_, &used_next_blocker))
569 // Here we have to handle any other input file types we need.
570 gold_error(_("%s: not an object or archive"),
571 this->input_file_->file().filename().c_str());
574 if (!used_next_blocker)
576 // Queue up a task to unlock next_blocker. We can't just unlock
577 // it here, as we don't hold the workqueue lock.
578 workqueue->queue_soon(new Unblock_token(NULL, this->next_blocker_));
582 // Return a debugging name for a Read_script task.
585 Read_script::get_name() const
587 std::string ret("Read_script ");
588 if (this->input_argument_->file().is_lib())
590 ret += this->input_argument_->file().name();
594 } // End namespace gold.