1// readsyms.cc -- read input file symbols for gold
2
3// Copyright (C) 2006-2017 Free Software Foundation, Inc.
4// Written by Ian Lance Taylor <iant@google.com>.
5
6// This file is part of gold.
7
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.
12
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.
17
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.
22
23#include "gold.h"
24
25#include <cstring>
26
27#include "elfcpp.h"
28#include "options.h"
29#include "dirsearch.h"
30#include "symtab.h"
31#include "object.h"
32#include "archive.h"
33#include "script.h"
34#include "readsyms.h"
35#include "plugin.h"
36#include "layout.h"
37#include "incremental.h"
38
39namespace gold
40{
41
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.
48
49class Unblock_token : public Task
50{
51 public:
52  Unblock_token(Task_token* this_blocker, Task_token* next_blocker)
53    : this_blocker_(this_blocker), next_blocker_(next_blocker)
54  { }
55
56  ~Unblock_token()
57  {
58    if (this->this_blocker_ != NULL)
59      delete this->this_blocker_;
60  }
61
62  Task_token*
63  is_runnable()
64  {
65    if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
66      return this->this_blocker_;
67    return NULL;
68  }
69
70  void
71  locks(Task_locker* tl)
72  { tl->add(this, this->next_blocker_); }
73
74  void
75  run(Workqueue*)
76  { }
77
78  std::string
79  get_name() const
80  { return "Unblock_token"; }
81
82 private:
83  Task_token* this_blocker_;
84  Task_token* next_blocker_;
85};
86
87// Class read_symbols.
88
89Read_symbols::~Read_symbols()
90{
91  // The this_blocker_ and next_blocker_ pointers are passed on to the
92  // Add_symbols task.
93}
94
95// If appropriate, issue a warning about skipping an incompatible
96// file.
97
98void
99Read_symbols::incompatible_warning(const Input_argument* input_argument,
100				   const Input_file* input_file)
101{
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());
106}
107
108// Requeue a Read_symbols task to search for the next object with the
109// same name.
110
111void
112Read_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)
117{
118  // Bump the directory search index.
119  ++dirindex;
120
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);
127
128  workqueue->queue(new Read_symbols(input_objects, symtab, layout, dirpath,
129				    dirindex, mapfile, input_argument,
130				    input_group, NULL, NULL, next_blocker));
131}
132
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.
136
137Task_token*
138Read_symbols::is_runnable()
139{
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();
144
145  return NULL;
146}
147
148// Return a Task_locker for a Read_symbols task.  We don't need any
149// locks here.
150
151void
152Read_symbols::locks(Task_locker* tl)
153{
154  if (this->member_ != NULL)
155    tl->add(this, this->next_blocker_);
156}
157
158// Run a Read_symbols task.
159
160void
161Read_symbols::run(Workqueue* workqueue)
162{
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_));
170}
171
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.
174
175bool
176Read_symbols::do_whole_lib_group(Workqueue* workqueue)
177{
178  const Input_file_lib* lib_group = this->input_argument_->lib();
179
180  ++Lib_group::total_lib_groups;
181
182  Task_token* this_blocker = this->this_blocker_;
183  for (Input_file_lib::const_iterator i = lib_group->begin();
184       i != lib_group->end();
185       ++i)
186    {
187      ++Lib_group::total_members;
188      ++Lib_group::total_members_loaded;
189
190      const Input_argument* arg = &*i;
191
192      Task_token* next_blocker;
193      if (i != lib_group->end() - 1)
194        {
195          next_blocker = new Task_token(true);
196          next_blocker->add_blocker();
197        }
198      else
199        next_blocker = this->next_blocker_;
200
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;
207    }
208
209  return true;
210}
211
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.
216
217bool
218Read_symbols::do_lib_group(Workqueue* workqueue)
219{
220  const Input_file_lib* lib_group = this->input_argument_->lib();
221
222  if (lib_group->options().whole_archive())
223    return this->do_whole_lib_group(workqueue);
224
225  Lib_group* lib = new Lib_group(lib_group, this);
226
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_);
231
232
233  Task_token* next_blocker = new Task_token(true);
234  int j = 0;
235  for (Input_file_lib::const_iterator i = lib_group->begin();
236       i != lib_group->end();
237       ++i, ++j)
238    {
239      const Input_argument* arg = &*i;
240      Archive_member* m = lib->get_member(j);
241
242      next_blocker->add_blocker();
243
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));
251    }
252
253  add_lib_group_symbols->set_blocker(next_blocker, this->this_blocker_);
254  workqueue->queue_soon(add_lib_group_symbols);
255
256  return true;
257}
258
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.
261
262bool
263Read_symbols::do_read_symbols(Workqueue* workqueue)
264{
265  if (this->input_argument_->is_group())
266    {
267      gold_assert(this->input_group_ == NULL);
268      this->do_group(workqueue);
269      return true;
270    }
271
272  if (this->input_argument_->is_lib())
273    return this->do_lib_group(workqueue);
274
275  Input_file* input_file = new Input_file(&this->input_argument_->file());
276  if (!input_file->open(*this->dirpath_, this, &this->dirindex_))
277    return false;
278
279  // Read enough of the file to pick up the entire ELF header.
280
281  off_t filesize = input_file->file().filesize();
282
283  if (filesize == 0)
284    {
285      gold_error(_("%s: file is empty"),
286		 input_file->file().filename().c_str());
287      return false;
288    }
289
290  const unsigned char* ehdr;
291  int read_size;
292  bool is_elf = is_elf_object(input_file, 0, &ehdr, &read_size);
293
294  if (read_size >= Archive::sarmag)
295    {
296      bool is_thin_archive
297          = memcmp(ehdr, Archive::armagt, Archive::sarmag) == 0;
298      if (is_thin_archive
299          || memcmp(ehdr, Archive::armag, Archive::sarmag) == 0)
300	{
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);
305	  arch->setup();
306
307	  // Unlock the archive so it can be used in the next task.
308	  arch->unlock(this);
309
310	  workqueue->queue_next(new Add_archive_symbols(this->symtab_,
311							this->layout_,
312							this->input_objects_,
313							this->dirpath_,
314							this->dirindex_,
315							this->mapfile_,
316							this->input_argument_,
317							arch,
318							this->input_group_,
319							this->this_blocker_,
320							this->next_blocker_));
321	  return true;
322	}
323    }
324
325  Object* elf_obj = NULL;
326  bool unconfigured;
327  bool* punconfigured = NULL;
328  if (is_elf)
329    {
330      // This is an ELF object.
331
332      unconfigured = false;
333      punconfigured = (input_file->will_search_for()
334		       ? &unconfigured
335		       : NULL);
336      elf_obj = make_elf_object(input_file->filename(),
337				input_file, 0, ehdr, read_size,
338				punconfigured);
339    }
340
341  if (parameters->options().has_plugins())
342    {
343      Pluginobj* obj = parameters->options().plugins()->claim_file(input_file,
344                                                                   0, filesize,
345								   elf_obj);
346      if (obj != NULL)
347        {
348	  // Delete the elf_obj, this file has been claimed.
349	  if (elf_obj != NULL)
350	    delete elf_obj;
351
352          // The input file was claimed by a plugin, and its symbols
353          // have been provided by the plugin.
354
355          // We are done with the file at this point, so unlock it.
356          obj->unlock(this);
357
358          if (this->member_ != NULL)
359	    {
360	      this->member_->sd_ = NULL;
361	      this->member_->obj_ = obj;
362	      return true;
363	    }
364
365          workqueue->queue_next(new Add_symbols(this->input_objects_,
366                                                this->symtab_,
367                                                this->layout_,
368						this->dirpath_,
369						this->dirindex_,
370						this->mapfile_,
371						this->input_argument_,
372                                                obj,
373                                                NULL,
374						NULL,
375                                                this->this_blocker_,
376                                                this->next_blocker_));
377          return true;
378        }
379    }
380
381  if (is_elf)
382    {
383      // This is an ELF object.
384
385      if (elf_obj == NULL)
386	{
387	  if (unconfigured)
388	    {
389	      Read_symbols::incompatible_warning(this->input_argument_,
390						 input_file);
391	      input_file->file().release();
392	      input_file->file().unlock(this);
393	      delete input_file;
394	      ++this->dirindex_;
395	      return this->do_read_symbols(workqueue);
396	    }
397	  return false;
398	}
399
400      Read_symbols_data* sd = new Read_symbols_data;
401      elf_obj->read_symbols(sd);
402
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
409      // Add_symbols task.
410
411      input_file->file().unlock(this);
412
413      if (this->member_ != NULL)
414        {
415          this->member_->sd_ = sd;
416          this->member_->obj_ = elf_obj;
417          this->member_->arg_serial_ =
418              this->input_argument_->file().arg_serial();
419          return true;
420        }
421
422      // We use queue_next because everything is cached for this
423      // task to run right away if possible.
424
425      workqueue->queue_next(new Add_symbols(this->input_objects_,
426					    this->symtab_, this->layout_,
427					    this->dirpath_,
428					    this->dirindex_,
429					    this->mapfile_,
430					    this->input_argument_,
431					    elf_obj,
432					    NULL,
433					    sd,
434					    this->this_blocker_,
435					    this->next_blocker_));
436
437      return true;
438    }
439
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.
445
446  workqueue->queue_soon(new Read_script(this->symtab_,
447					this->layout_,
448					this->dirpath_,
449					this->dirindex_,
450					this->input_objects_,
451					this->mapfile_,
452					this->input_group_,
453					this->input_argument_,
454					input_file,
455					this->this_blocker_,
456					this->next_blocker_));
457  return true;
458}
459
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.
466
467void
468Read_symbols::do_group(Workqueue* workqueue)
469{
470  Input_group* input_group = new Input_group();
471
472  const Input_file_group* group = this->input_argument_->group();
473  Task_token* this_blocker = this->this_blocker_;
474
475  Finish_group* finish_group = new Finish_group(this->input_objects_,
476						this->symtab_,
477						this->layout_,
478						this->mapfile_,
479						input_group,
480						this->next_blocker_);
481
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;
487
488  for (Input_file_group::const_iterator p = group->begin();
489       p != group->end();
490       ++p)
491    {
492      const Input_argument* arg = &*p;
493      gold_assert(arg->is_file());
494
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;
503    }
504
505  finish_group->set_blocker(this_blocker);
506
507  workqueue->queue_soon(finish_group);
508}
509
510// Return a debugging name for a Read_symbols task.
511
512std::string
513Read_symbols::get_name() const
514{
515  if (this->input_argument_->is_group())
516    {
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();
521           p != group->end();
522           ++p)
523      {
524        if (add_space)
525          ret += ' ';
526        ret += p->file().name();
527        add_space = true;
528      }
529      return ret + ')';
530    }
531  else if (this->input_argument_->is_lib())
532    {
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();
537           p != lib->end();
538           ++p)
539      {
540        if (add_space)
541          ret += ' ';
542        ret += p->file().name();
543        add_space = true;
544      }
545      return ret + ')';
546    }
547  else
548    {
549      std::string ret("Read_symbols ");
550      if (this->input_argument_->file().is_lib())
551	ret += "-l";
552      else if (this->input_argument_->file().is_searched_file())
553	ret += "-l:";
554      ret += this->input_argument_->file().name();
555      return ret;
556    }
557}
558
559// Class Add_symbols.
560
561Add_symbols::~Add_symbols()
562{
563  if (this->this_blocker_ != NULL)
564    delete this->this_blocker_;
565  // next_blocker_ is deleted by the task associated with the next
566  // input file.
567}
568
569// We are blocked by this_blocker_.  We block next_blocker_.  We also
570// lock the file.
571
572Task_token*
573Add_symbols::is_runnable()
574{
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();
579  return NULL;
580}
581
582void
583Add_symbols::locks(Task_locker* tl)
584{
585  tl->add(this, this->next_blocker_);
586  Task_token* token = this->object_->token();
587  if (token != NULL)
588    tl->add(this, token);
589}
590
591// Add the symbols in the object to the symbol table.
592
593void
594Add_symbols::run(Workqueue*)
595{
596  Pluginobj* pluginobj = this->object_->pluginobj();
597  if (pluginobj != NULL)
598    {
599      this->object_->add_symbols(this->symtab_, this->sd_, this->layout_);
600      return;
601    }
602
603  if (!this->input_objects_->add_object(this->object_))
604    {
605      this->object_->discard_decompressed_sections();
606      gold_assert(this->sd_ != NULL);
607      delete this->sd_;
608      this->sd_ = NULL;
609      this->object_->release();
610      delete this->object_;
611    }
612  else
613    {
614      Incremental_inputs* incremental_inputs =
615          this->layout_->incremental_inputs();
616      if (incremental_inputs != NULL)
617	{
618          if (this->library_ != NULL && !this->library_->is_reported())
619            {
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_,
626						       lib_serial,
627						       lib_script_info);
628	    }
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);
633	}
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();
637      delete this->sd_;
638      this->sd_ = NULL;
639      this->object_->release();
640    }
641}
642
643// Class Read_member.
644
645Read_member::~Read_member()
646{
647  if (this->this_blocker_ != NULL)
648    delete this->this_blocker_;
649  // next_blocker_ is deleted by the task associated with the next
650  // input file.
651}
652
653// Return whether a Read_member task is runnable.
654
655Task_token*
656Read_member::is_runnable()
657{
658  if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
659    return this->this_blocker_;
660  return NULL;
661}
662
663void
664Read_member::locks(Task_locker* tl)
665{
666  tl->add(this, this->next_blocker_);
667}
668
669// Run a Read_member task.
670
671void
672Read_member::run(Workqueue*)
673{
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.
677}
678
679// Class Check_script.
680
681Check_script::~Check_script()
682{
683  if (this->this_blocker_ != NULL)
684    delete this->this_blocker_;
685  // next_blocker_ is deleted by the task associated with the next
686  // input file.
687}
688
689// Return whether a Check_script task is runnable.
690
691Task_token*
692Check_script::is_runnable()
693{
694  if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
695    return this->this_blocker_;
696  return NULL;
697}
698
699void
700Check_script::locks(Task_locker* tl)
701{
702  tl->add(this, this->next_blocker_);
703}
704
705// Run a Check_script task.
706
707void
708Check_script::run(Workqueue*)
709{
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);
717}
718
719// Class Check_library.
720
721Check_library::~Check_library()
722{
723  if (this->this_blocker_ != NULL)
724    delete this->this_blocker_;
725  // next_blocker_ is deleted by the task associated with the next
726  // input file.
727}
728
729// Return whether a Check_library task is runnable.
730
731Task_token*
732Check_library::is_runnable()
733{
734  if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
735    return this->this_blocker_;
736  return NULL;
737}
738
739void
740Check_library::locks(Task_locker* tl)
741{
742  tl->add(this, this->next_blocker_);
743}
744
745// Run a Check_library task.
746
747void
748Check_library::run(Workqueue*)
749{
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())
757    {
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);
762    }
763  incremental_inputs->report_archive_end(lib);
764}
765
766// Class Input_group.
767
768// When we delete an Input_group we can delete the archive
769// information.
770
771Input_group::~Input_group()
772{
773  for (Input_group::const_iterator p = this->begin();
774       p != this->end();
775       ++p)
776    delete *p;
777}
778
779// Class Start_group.
780
781Start_group::~Start_group()
782{
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.
787}
788
789// We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_.
790
791Task_token*
792Start_group::is_runnable()
793{
794  if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
795    return this->this_blocker_;
796  return NULL;
797}
798
799void
800Start_group::locks(Task_locker* tl)
801{
802  tl->add(this, this->next_blocker_);
803}
804
805// Store the number of undefined symbols we see now.
806
807void
808Start_group::run(Workqueue*)
809{
810  this->finish_group_->set_saw_undefined(this->symtab_->saw_undefined());
811}
812
813// Class Finish_group.
814
815Finish_group::~Finish_group()
816{
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.
821}
822
823// We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_.
824
825Task_token*
826Finish_group::is_runnable()
827{
828  if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
829    return this->this_blocker_;
830  return NULL;
831}
832
833void
834Finish_group::locks(Task_locker* tl)
835{
836  tl->add(this, this->next_blocker_);
837}
838
839// Loop over the archives until there are no new undefined symbols.
840
841void
842Finish_group::run(Workqueue*)
843{
844  size_t saw_undefined = this->saw_undefined_;
845  while (saw_undefined != this->symtab_->saw_undefined())
846    {
847      saw_undefined = this->symtab_->saw_undefined();
848
849      for (Input_group::const_iterator p = this->input_group_->begin();
850	   p != this->input_group_->end();
851	   ++p)
852	{
853	  Task_lock_obj<Archive> tl(this, *p);
854
855	  (*p)->add_symbols(this->symtab_, this->layout_,
856			    this->input_objects_, this->mapfile_);
857	}
858    }
859
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();
864       ++p)
865    {
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);
871    }
872
873  if (parameters->options().has_plugins())
874    parameters->options().plugins()->save_input_group(this->input_group_);
875  else
876    delete this->input_group_;
877}
878
879// Class Read_script
880
881Read_script::~Read_script()
882{
883  if (this->this_blocker_ != NULL)
884    delete this->this_blocker_;
885  // next_blocker_ is deleted by the task associated with the next
886  // input file.
887}
888
889// We are blocked by this_blocker_.
890
891Task_token*
892Read_script::is_runnable()
893{
894  if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
895    return this->this_blocker_;
896  return NULL;
897}
898
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.
901
902void
903Read_script::locks(Task_locker*)
904{
905}
906
907// Read the script, if it is a script.
908
909void
910Read_script::run(Workqueue* workqueue)
911{
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))
918    {
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());
922    }
923
924  if (!used_next_blocker)
925    {
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_));
929    }
930}
931
932// Return a debugging name for a Read_script task.
933
934std::string
935Read_script::get_name() const
936{
937  std::string ret("Read_script ");
938  if (this->input_argument_->file().is_lib())
939    ret += "-l";
940  else if (this->input_argument_->file().is_searched_file())
941    ret += "-l:";
942  ret += this->input_argument_->file().name();
943  return ret;
944}
945
946} // End namespace gold.
947