aboutsummaryrefslogtreecommitdiff
path: root/gold/archive.cc
blob: 23cb0be30019b9d94d30ec14aba98d8692be3065 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
// archive.cc -- archive support for gold

// Copyright (C) 2006-2014 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.

// This file is part of gold.

// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
// MA 02110-1301, USA.

#include "gold.h"

#include <cerrno>
#include <cstring>
#include <climits>
#include <vector>
#include "libiberty.h"
#include "filenames.h"

#include "elfcpp.h"
#include "options.h"
#include "mapfile.h"
#include "fileread.h"
#include "readsyms.h"
#include "symtab.h"
#include "object.h"
#include "layout.h"
#include "archive.h"
#include "plugin.h"
#include "incremental.h"

namespace gold
{

// Library_base methods.

// Determine whether a definition of SYM_NAME should cause an archive
// library member to be included in the link.  Returns SHOULD_INCLUDE_YES
// if the symbol is referenced but not defined, SHOULD_INCLUDE_NO if the
// symbol is already defined, and SHOULD_INCLUDE_UNKNOWN if the symbol is
// neither referenced nor defined.

Library_base::Should_include
Library_base::should_include_member(Symbol_table* symtab, Layout* layout,
				    const char* sym_name, Symbol** symp,
				    std::string* why, char** tmpbufp,
				    size_t* tmpbuflen)
{
  // In an object file, and therefore in an archive map, an
  // '@' in the name separates the symbol name from the
  // version name.  If there are two '@' characters, this is
  // the default version.
  char* tmpbuf = *tmpbufp;
  const char* ver = strchr(sym_name, '@');
  bool def = false;
  if (ver != NULL)
    {
      size_t symlen = ver - sym_name;
      if (symlen + 1 > *tmpbuflen)
        {
          tmpbuf = static_cast<char*>(xrealloc(tmpbuf, symlen + 1));
          *tmpbufp = tmpbuf;
          *tmpbuflen = symlen + 1;
        }
      memcpy(tmpbuf, sym_name, symlen);
      tmpbuf[symlen] = '\0';
      sym_name = tmpbuf;

      ++ver;
      if (*ver == '@')
        {
          ++ver;
          def = true;
        }
    }

  Symbol* sym = symtab->lookup(sym_name, ver);
  if (def
      && ver != NULL
      && (sym == NULL
          || !sym->is_undefined()
          || sym->binding() == elfcpp::STB_WEAK))
    sym = symtab->lookup(sym_name, NULL);

  *symp = sym;

  if (sym != NULL)
    {
      if (!sym->is_undefined())
	return Library_base::SHOULD_INCLUDE_NO;

      // PR 12001: Do not include an archive when the undefined
      // symbol has actually been defined on the command line.
      if (layout->script_options()->is_pending_assignment(sym_name))
	return Library_base::SHOULD_INCLUDE_NO;

      // If the symbol is weak undefined, we still need to check
      // for other reasons (like a -u option).
      if (sym->binding() != elfcpp::STB_WEAK)
	return Library_base::SHOULD_INCLUDE_YES;
    }

  // Check whether the symbol was named in a -u option.
  if (parameters->options().is_undefined(sym_name))
    {
      *why = "-u ";
      *why += sym_name;
      return Library_base::SHOULD_INCLUDE_YES;
    }

  if (parameters->options().is_export_dynamic_symbol(sym_name))
    {
      *why = "--export-dynamic-symbol ";
      *why += sym_name;
      return Library_base::SHOULD_INCLUDE_YES;
    }

  if (layout->script_options()->is_referenced(sym_name))
    {
      size_t alc = 100 + strlen(sym_name);
      char* buf = new char[alc];
      snprintf(buf, alc, _("script or expression reference to %s"),
	       sym_name);
      *why = buf;
      delete[] buf;
      return Library_base::SHOULD_INCLUDE_YES;
    }

  if (strcmp(sym_name, parameters->entry()) == 0)
    {
      *why = "entry symbol ";
      *why += sym_name;
      return Library_base::SHOULD_INCLUDE_YES;
    }

  return Library_base::SHOULD_INCLUDE_UNKNOWN;
}

// The header of an entry in the archive.  This is all readable text,
// padded with spaces where necessary.  If the contents of an archive
// are all text file, the entire archive is readable.

struct Archive::Archive_header
{
  // The entry name.
  char ar_name[16];
  // The file modification time.
  char ar_date[12];
  // The user's UID in decimal.
  char ar_uid[6];
  // The user's GID in decimal.
  char ar_gid[6];
  // The file mode in octal.
  char ar_mode[8];
  // The file size in decimal.
  char ar_size[10];
  // The final magic code.
  char ar_fmag[2];
};

// Class Archive static variables.
unsigned int Archive::total_archives;
unsigned int Archive::total_members;
unsigned int Archive::total_members_loaded;

// Archive methods.

const char Archive::armag[sarmag] =
{
  '!', '<', 'a', 'r', 'c', 'h', '>', '\n'
};

const char Archive::armagt[sarmag] =
{
  '!', '<', 't', 'h', 'i', 'n', '>', '\n'
};

const char Archive::arfmag[2] = { '`', '\n' };

Archive::Archive(const std::string& name, Input_file* input_file,
                 bool is_thin_archive, Dirsearch* dirpath, Task* task)
  : Library_base(task), name_(name), input_file_(input_file), armap_(),
    armap_names_(), extended_names_(), armap_checked_(), seen_offsets_(),
    members_(), is_thin_archive_(is_thin_archive), included_member_(false),
    nested_archives_(), dirpath_(dirpath), num_members_(0),
    included_all_members_(false)
{
  this->no_export_ =
    parameters->options().check_excluded_libs(input_file->found_name());
}

// Set up the archive: read the symbol map and the extended name
// table.

void
Archive::setup()
{
  // We need to ignore empty archives.
  if (this->input_file_->file().filesize() == sarmag)
    return;

  // The first member of the archive should be the symbol table.
  std::string armap_name;
  off_t header_size = this->read_header(sarmag, false, &armap_name, NULL);
  if (header_size == -1)
    return;

  section_size_type armap_size = convert_to_section_size_type(header_size);
  off_t off = sarmag;
  if (armap_name.empty())
    {
      this->read_armap(sarmag + sizeof(Archive_header), armap_size);
      off = sarmag + sizeof(Archive_header) + armap_size;
    }
  else if (!this->input_file_->options().whole_archive())
    gold_error(_("%s: no archive symbol table (run ranlib)"),
	       this->name().c_str());

  // See if there is an extended name table.  We cache these views
  // because it is likely that we will want to read the following
  // header in the add_symbols routine.
  if ((off & 1) != 0)
    ++off;
  std::string xname;
  header_size = this->read_header(off, true, &xname, NULL);
  if (header_size == -1)
    return;

  section_size_type extended_size = convert_to_section_size_type(header_size);
  if (xname == "/")
    {
      const unsigned char* p = this->get_view(off + sizeof(Archive_header),
                                              extended_size, false, true);
      const char* px = reinterpret_cast<const char*>(p);
      this->extended_names_.assign(px, extended_size);
    }
  bool preread_syms = (parameters->options().threads()
                       && parameters->options().preread_archive_symbols());
#ifndef ENABLE_THREADS
  preread_syms = false;
#else
  if (parameters->options().has_plugins())
    preread_syms = false;
#endif
  if (preread_syms)
    this->read_all_symbols();
}

// Unlock any nested archives.

void
Archive::unlock_nested_archives()
{
  for (Nested_archive_table::iterator p = this->nested_archives_.begin();
       p != this->nested_archives_.end();
       ++p)
    {
      p->second->unlock(this->task_);
    }
}

// Read the archive symbol map.

void
Archive::read_armap(off_t start, section_size_type size)
{
  // To count the total number of archive members, we'll just count
  // the number of times the file offset changes.  Since most archives
  // group the symbols in the armap by object, this ought to give us
  // an accurate count.
  off_t last_seen_offset = -1;

  // Read in the entire armap.
  const unsigned char* p = this->get_view(start, size, true, false);

  // Numbers in the armap are always big-endian.
  const elfcpp::Elf_Word* pword = reinterpret_cast<const elfcpp::Elf_Word*>(p);
  unsigned int nsyms = elfcpp::Swap<32, true>::readval(pword);
  ++pword;

  // Note that the addition is in units of sizeof(elfcpp::Elf_Word).
  const char* pnames = reinterpret_cast<const char*>(pword + nsyms);
  section_size_type names_size =
    reinterpret_cast<const char*>(p) + size - pnames;
  this->armap_names_.assign(pnames, names_size);

  this->armap_.resize(nsyms);

  section_offset_type name_offset = 0;
  for (unsigned int i = 0; i < nsyms; ++i)
    {
      this->armap_[i].name_offset = name_offset;
      this->armap_[i].file_offset = elfcpp::Swap<32, true>::readval(pword);
      name_offset += strlen(pnames + name_offset) + 1;
      ++pword;
      if (this->armap_[i].file_offset != last_seen_offset)
        {
          last_seen_offset = this->armap_[i].file_offset;
          ++this->num_members_;
        }
    }

  if (static_cast<section_size_type>(name_offset) > names_size)
    gold_error(_("%s: bad archive symbol table names"),
	       this->name().c_str());

  // This array keeps track of which symbols are for archive elements
  // which we have already included in the link.
  this->armap_checked_.resize(nsyms);
}

// Read the header of an archive member at OFF.  Fail if something
// goes wrong.  Return the size of the member.  Set *PNAME to the name
// of the member.

off_t
Archive::read_header(off_t off, bool cache, std::string* pname,
                     off_t* nested_off)
{
  const unsigned char* p = this->get_view(off, sizeof(Archive_header), true,
					  cache);
  const Archive_header* hdr = reinterpret_cast<const Archive_header*>(p);
  return this->interpret_header(hdr, off,  pname, nested_off);
}

// Interpret the header of HDR, the header of the archive member at
// file offset OFF.  Return the size of the member, or -1 if something
// has gone wrong.  Set *PNAME to the name of the member.

off_t
Archive::interpret_header(const Archive_header* hdr, off_t off,
                          std::string* pname, off_t* nested_off) const
{
  if (memcmp(hdr->ar_fmag, arfmag, sizeof arfmag) != 0)
    {
      gold_error(_("%s: malformed archive header at %zu"),
		 this->name().c_str(), static_cast<size_t>(off));
      return -1;
    }

  const int size_string_size = sizeof hdr->ar_size;
  char size_string[size_string_size + 1];
  memcpy(size_string, hdr->ar_size, size_string_size);
  char* ps = size_string + size_string_size;
  while (ps[-1] == ' ')
    --ps;
  *ps = '\0';

  errno = 0;
  char* end;
  off_t member_size = strtol(size_string, &end, 10);
  if (*end != '\0'
      || member_size < 0
      || (member_size == LONG_MAX && errno == ERANGE))
    {
      gold_error(_("%s: malformed archive header size at %zu"),
		 this->name().c_str(), static_cast<size_t>(off));
      return -1;
    }

  if (hdr->ar_name[0] != '/')
    {
      const char* name_end = strchr(hdr->ar_name, '/');
      if (name_end == NULL
	  || name_end - hdr->ar_name >= static_cast<int>(sizeof hdr->ar_name))
	{
	  gold_error(_("%s: malformed archive header name at %zu"),
		     this->name().c_str(), static_cast<size_t>(off));
	  return -1;
	}
      pname->assign(hdr->ar_name, name_end - hdr->ar_name);
      if (nested_off != NULL)
        *nested_off = 0;
    }
  else if (hdr->ar_name[1] == ' ')
    {
      // This is the symbol table.
      if (!pname->empty())
	pname->clear();
    }
  else if (hdr->ar_name[1] == '/')
    {
      // This is the extended name table.
      pname->assign(1, '/');
    }
  else
    {
      errno = 0;
      long x = strtol(hdr->ar_name + 1, &end, 10);
      long y = 0;
      if (*end == ':')
        y = strtol(end + 1, &end, 10);
      if (*end != ' '
	  || x < 0
	  || (x == LONG_MAX && errno == ERANGE)
	  || static_cast<size_t>(x) >= this->extended_names_.size())
	{
	  gold_error(_("%s: bad extended name index at %zu"),
		     this->name().c_str(), static_cast<size_t>(off));
	  return -1;
	}

      const char* name = this->extended_names_.data() + x;
      const char* name_end = strchr(name, '\n');
      if (static_cast<size_t>(name_end - name) > this->extended_names_.size()
	  || name_end[-1] != '/')
	{
	  gold_error(_("%s: bad extended name entry at header %zu"),
		     this->name().c_str(), static_cast<size_t>(off));
	  return -1;
	}
      pname->assign(name, name_end - 1 - name);
      if (nested_off != NULL)
        *nested_off = y;
    }

  return member_size;
}

// An archive member iterator.

class Archive::const_iterator
{
 public:
  // The header of an archive member.  This is what this iterator
  // points to.
  struct Header
  {
    // The name of the member.
    std::string name;
    // The file offset of the member.
    off_t off;
    // The file offset of a nested archive member.
    off_t nested_off;
    // The size of the member.
    off_t size;
  };

  const_iterator(Archive* archive, off_t off)
    : archive_(archive), off_(off)
  { this->read_next_header(); }

  const Header&
  operator*() const
  { return this->header_; }

  const Header*
  operator->() const
  { return &this->header_; }

  const_iterator&
  operator++()
  {
    if (this->off_ == this->archive_->file().filesize())
      return *this;
    this->off_ += sizeof(Archive_header);
    if (!this->archive_->is_thin_archive())
      this->off_ += this->header_.size;
    if ((this->off_ & 1) != 0)
      ++this->off_;
    this->read_next_header();
    return *this;
  }

  const_iterator
  operator++(int)
  {
    const_iterator ret = *this;
    ++*this;
    return ret;
  }

  bool
  operator==(const const_iterator p) const
  { return this->off_ == p->off; }

  bool
  operator!=(const const_iterator p) const
  { return this->off_ != p->off; }

 private:
  void
  read_next_header();

  // The underlying archive.
  Archive* archive_;
  // The current offset in the file.
  off_t off_;
  // The current archive header.
  Header header_;
};

// Read the next archive header.

void
Archive::const_iterator::read_next_header()
{
  off_t filesize = this->archive_->file().filesize();
  while (true)
    {
      if (filesize - this->off_ < static_cast<off_t>(sizeof(Archive_header)))
	{
	  if (filesize != this->off_)
	    {
	      gold_error(_("%s: short archive header at %zu"),
			 this->archive_->filename().c_str(),
			 static_cast<size_t>(this->off_));
	      this->off_ = filesize;
	    }
	  this->header_.off = filesize;
	  return;
	}

      unsigned char buf[sizeof(Archive_header)];
      this->archive_->file().read(this->off_, sizeof(Archive_header), buf);

      const Archive_header* hdr = reinterpret_cast<const Archive_header*>(buf);
      off_t size = this->archive_->interpret_header(hdr, this->off_,
						    &this->header_.name,
						    &this->header_.nested_off);
      if (size == -1)
	{
	  this->header_.off = filesize;
	  return;
	}

      this->header_.size = size;
      this->header_.off = this->off_;

      // Skip special members.
      if (!this->header_.name.empty() && this->header_.name != "/")
	return;

      this->off_ += sizeof(Archive_header) + this->header_.size;
      if ((this->off_ & 1) != 0)
	++this->off_;
    }
}

// Initial iterator.

Archive::const_iterator
Archive::begin()
{
  return Archive::const_iterator(this, sarmag);
}

// Final iterator.

Archive::const_iterator
Archive::end()
{
  return Archive::const_iterator(this, this->input_file_->file().filesize());
}

// Get the file and offset for an archive member, which may be an
// external member of a thin archive.  Set *INPUT_FILE to the
// file containing the actual member, *MEMOFF to the offset
// within that file (0 if not a nested archive), and *MEMBER_NAME
// to the name of the archive member.  Return TRUE on success.

bool
Archive::get_file_and_offset(off_t off, Input_file** input_file, off_t* memoff,
                             off_t* memsize, std::string* member_name)
{
  off_t nested_off;

  *memsize = this->read_header(off, false, member_name, &nested_off);
  if (*memsize == -1)
    return false;

  *input_file = this->input_file_;
  *memoff = off + static_cast<off_t>(sizeof(Archive_header));

  if (!this->is_thin_archive_)
    return true;

  // Adjust a relative pathname so that it is relative
  // to the directory containing the archive.
  if (!IS_ABSOLUTE_PATH(member_name->c_str()))
    {
      const char* arch_path = this->filename().c_str();
      const char* basename = lbasename(arch_path);
      if (basename > arch_path)
        member_name->replace(0, 0,
                             this->filename().substr(0, basename - arch_path));
    }

  if (nested_off > 0)
    {
      // This is a member of a nested archive.  Open the containing
      // archive if we don't already have it open, then do a recursive
      // call to include the member from that archive.
      Archive* arch;
      Nested_archive_table::const_iterator p =
        this->nested_archives_.find(*member_name);
      if (p != this->nested_archives_.end())
        arch = p->second;
      else
        {
          Input_file_argument* input_file_arg =
            new Input_file_argument(member_name->c_str(),
                                    Input_file_argument::INPUT_FILE_TYPE_FILE,
                                    "", false, parameters->options());
          *input_file = new Input_file(input_file_arg);
	  int dummy = 0;
          if (!(*input_file)->open(*this->dirpath_, this->task_, &dummy))
            return false;
          arch = new Archive(*member_name, *input_file, false, this->dirpath_,
                             this->task_);
          arch->setup();
          std::pair<Nested_archive_table::iterator, bool> ins =
            this->nested_archives_.insert(std::make_pair(*member_name, arch));
          gold_assert(ins.second);
        }
      return arch->get_file_and_offset(nested_off, input_file, memoff,
				       memsize, member_name);
    }

  // This is an external member of a thin archive.  Open the
  // file as a regular relocatable object file.
  Input_file_argument* input_file_arg =
      new Input_file_argument(member_name->c_str(),
                              Input_file_argument::INPUT_FILE_TYPE_FILE,
                              "", false, this->input_file_->options());
  *input_file = new Input_file(input_file_arg);
  int dummy = 0;
  if (!(*input_file)->open(*this->dirpath_, this->task_, &dummy))
    return false;

  *memoff = 0;
  *memsize = (*input_file)->file().filesize();
  return true;
}

// Return an ELF object for the member at offset OFF.  If
// PUNCONFIGURED is not NULL, then if the ELF object has an
// unsupported target type, set *PUNCONFIGURED to true and return
// NULL.

Object*
Archive::get_elf_object_for_member(off_t off, bool* punconfigured)
{
  if (punconfigured != NULL)
    *punconfigured = false;

  Input_file* input_file;
  off_t memoff;
  off_t memsize;
  std::string member_name;
  if (!this->get_file_and_offset(off, &input_file, &memoff, &memsize,
				 &member_name))
    return NULL;

  const unsigned char* ehdr;
  int read_size;
  Object *obj = NULL;
  bool is_elf_obj = false;

  if (is_elf_object(input_file, memoff, &ehdr, &read_size))
    {
      obj = make_elf_object((std::string(this->input_file_->filename())
			     + "(" + member_name + ")"),
			    input_file, memoff, ehdr, read_size,
			    punconfigured);
      is_elf_obj = true;
    }

  if (parameters->options().has_plugins())
    {
      Object* plugin_obj
	= parameters->options().plugins()->claim_file(input_file,
						      memoff,
						      memsize,
						      obj);
      if (plugin_obj != NULL)
        {
          // The input file was claimed by a plugin, and its symbols
          // have been provided by the plugin.
	  // Delete its elf object.
	  if (obj != NULL)
	    delete obj;
          return plugin_obj;
        }
    }

  if (!is_elf_obj)
    {
      gold_error(_("%s: member at %zu is not an ELF object"),
		 this->name().c_str(), static_cast<size_t>(off));
      return NULL;
    }

  if (obj == NULL)
    return NULL;
  obj->set_no_export(this->no_export());
  return obj;
}

// Read the symbols from all the archive members in the link.

void
Archive::read_all_symbols()
{
  for (Archive::const_iterator p = this->begin();
       p != this->end();
       ++p)
    this->read_symbols(p->off);
}

// Read the symbols from an archive member in the link.  OFF is the file
// offset of the member header.

void
Archive::read_symbols(off_t off)
{
  Object* obj = this->get_elf_object_for_member(off, NULL);
  if (obj == NULL)
    return;

  Read_symbols_data* sd = new Read_symbols_data;
  obj->read_symbols(sd);
  Archive_member member(obj, sd);
  this->members_[off] = member;
}

// Select members from the archive and add them to the link.  We walk
// through the elements in the archive map, and look each one up in
// the symbol table.  If it exists as a strong undefined symbol, we
// pull in the corresponding element.  We have to do this in a loop,
// since pulling in one element may create new undefined symbols which
// may be satisfied by other objects in the archive.  Return true in
// the normal case, false if the first member we tried to add from
// this archive had an incompatible target.

bool
Archive::add_symbols(Symbol_table* symtab, Layout* layout,
		     Input_objects* input_objects, Mapfile* mapfile)
{
  ++Archive::total_archives;

  if (this->input_file_->options().whole_archive())
    return this->include_all_members(symtab, layout, input_objects,
				     mapfile);

  Archive::total_members += this->num_members_;

  input_objects->archive_start(this);

  const size_t armap_size = this->armap_.size();

  // This is a quick optimization, since we usually see many symbols
  // in a row with the same offset.  last_seen_offset holds the last
  // offset we saw that was present in the seen_offsets_ set.
  off_t last_seen_offset = -1;

  // Track which symbols in the symbol table we've already found to be
  // defined.

  char* tmpbuf = NULL;
  size_t tmpbuflen = 0;
  bool added_new_object;
  do
    {
      added_new_object = false;
      for (size_t i = 0; i < armap_size; ++i)
	{
          if (this->armap_checked_[i])
            continue;
	  if (this->armap_[i].file_offset == last_seen_offset)
            {
              this->armap_checked_[i] = true;
              continue;
            }
	  if (this->seen_offsets_.find(this->armap_[i].file_offset)
              != this->seen_offsets_.end())
	    {
              this->armap_checked_[i] = true;
	      last_seen_offset = this->armap_[i].file_offset;
	      continue;
	    }

	  const char* sym_name = (this->armap_names_.data()
				  + this->armap_[i].name_offset);

          Symbol* sym;
          std::string why;
          Archive::Should_include t =
	    Archive::should_include_member(symtab, layout, sym_name, &sym,
					   &why, &tmpbuf, &tmpbuflen);

	  if (t == Archive::SHOULD_INCLUDE_NO
              || t == Archive::SHOULD_INCLUDE_YES)
	    this->armap_checked_[i] = true;

	  if (t != Archive::SHOULD_INCLUDE_YES)
	    continue;

	  // We want to include this object in the link.
	  last_seen_offset = this->armap_[i].file_offset;
	  this->seen_offsets_.insert(last_seen_offset);

	  if (!this->include_member(symtab, layout, input_objects,
				    last_seen_offset, mapfile, sym,
				    why.c_str()))
	    {
	      if (tmpbuf != NULL)
		free(tmpbuf);
	      return false;
	    }

	  added_new_object = true;
	}
    }
  while (added_new_object);

  if (tmpbuf != NULL)
    free(tmpbuf);

  input_objects->archive_stop(this);

  return true;
}

// Return whether the archive includes a member which defines the
// symbol SYM.

bool
Archive::defines_symbol(Symbol* sym) const
{
  const char* symname = sym->name();
  size_t symname_len = strlen(symname);
  size_t armap_size = this->armap_.size();
  for (size_t i = 0; i < armap_size; ++i)
    {
      if (this->armap_checked_[i])
	continue;
      const char* archive_symname = (this->armap_names_.data()
				     + this->armap_[i].name_offset);
      if (strncmp(archive_symname, symname, symname_len) != 0)
	continue;
      char c = archive_symname[symname_len];
      if (c == '\0' && sym->version() == NULL)
	return true;
      if (c == '@')
	{
	  const char* ver = archive_symname + symname_len + 1;
	  if (*ver == '@')
	    {
	      if (sym->version() == NULL)
		return true;
	      ++ver;
	    }
	  if (sym->version() != NULL && strcmp(sym->version(), ver) == 0)
	    return true;
	}
    }
  return false;
}

// Include all the archive members in the link.  This is for --whole-archive.

bool
Archive::include_all_members(Symbol_table* symtab, Layout* layout,
                             Input_objects* input_objects, Mapfile* mapfile)
{
  // Don't include the same archive twice.  This can happen if
  // --whole-archive is nested inside --start-group (PR gold/12163).
  if (this->included_all_members_)
    return true;

  this->included_all_members_ = true;

  input_objects->archive_start(this);

  if (this->members_.size() > 0)
    {
      std::map<off_t, Archive_member>::const_iterator p;
      for (p = this->members_.begin();
           p != this->members_.end();
           ++p)
        {
          if (!this->include_member(symtab, layout, input_objects, p->first,
				    mapfile, NULL, "--whole-archive"))
	    return false;
          ++Archive::total_members;
        }
    }
  else
    {
      for (Archive::const_iterator p = this->begin();
           p != this->end();
           ++p)
        {
          if (!this->include_member(symtab, layout, input_objects, p->off,
				    mapfile, NULL, "--whole-archive"))
	    return false;
          ++Archive::total_members;
        }
    }

  input_objects->archive_stop(this);

  return true;
}

// Return the number of members in the archive.  This is only used for
// reports.

size_t
Archive::count_members()
{
  size_t ret = 0;
  for (Archive::const_iterator p = this->begin();
       p != this->end();
       ++p)
    ++ret;
  return ret;
}

// Include an archive member in the link.  OFF is the file offset of
// the member header.  WHY is the reason we are including this member.
// Return true if we added the member or if we had an error, return
// false if this was the first member we tried to add from this
// archive and it had an incompatible format.

bool
Archive::include_member(Symbol_table* symtab, Layout* layout,
			Input_objects* input_objects, off_t off,
			Mapfile* mapfile, Symbol* sym, const char* why)
{
  ++Archive::total_members_loaded;

  std::map<off_t, Archive_member>::const_iterator p = this->members_.find(off);
  if (p != this->members_.end())
    {
      Object* obj = p->second.obj_;

      Read_symbols_data* sd = p->second.sd_;
      if (mapfile != NULL)
        mapfile->report_include_archive_member(obj->name(), sym, why);
      if (input_objects->add_object(obj))
        {
          obj->layout(symtab, layout, sd);
          obj->add_symbols(symtab, sd, layout);
	  this->included_member_ = true;
        }
      delete sd;
      return true;
    }

  // If this is the first object we are including from this archive,
  // and we searched for this archive, most likely because it was
  // found via a -l option, then if the target is incompatible we want
  // to move on to the next archive found in the search path.
  bool unconfigured = false;
  bool* punconfigured = NULL;
  if (!this->included_member_ && this->searched_for())
    punconfigured = &unconfigured;

  Object* obj = this->get_elf_object_for_member(off, punconfigured);
  if (obj == NULL)
    {
      // Return false to search for another archive, true if we found
      // an error.
      return unconfigured ? false : true;
    }

  if (mapfile != NULL)
    mapfile->report_include_archive_member(obj->name(), sym, why);

  Pluginobj* pluginobj = obj->pluginobj();
  if (pluginobj != NULL)
    {
      pluginobj->add_symbols(symtab, NULL, layout);
      this->included_member_ = true;
      return true;
    }

  if (!input_objects->add_object(obj))
    {
      // If this is an external member of a thin archive, unlock the
      // file.
      if (obj->offset() == 0)
	obj->unlock(this->task_);
      delete obj;
    }
  else
    {
      {
	if (layout->incremental_inputs() != NULL)
	  layout->incremental_inputs()->report_object(obj, 0, this, NULL);
	Read_symbols_data sd;
	obj->read_symbols(&sd);
	obj->layout(symtab, layout, &sd);
	obj->add_symbols(symtab, &sd, layout);
      }

      // If this is an external member of a thin archive, unlock the file
      // for the next task.
      if (obj->offset() == 0)
        obj->unlock(this->task_);

      this->included_member_ = true;
    }

  return true;
}

// Iterate over all unused symbols, and call the visitor class V for each.

void
Archive::do_for_all_unused_symbols(Symbol_visitor_base* v) const
{
  for (std::vector<Armap_entry>::const_iterator p = this->armap_.begin();
       p != this->armap_.end();
       ++p)
    {
      if (this->seen_offsets_.find(p->file_offset)
          == this->seen_offsets_.end())
        v->visit(this->armap_names_.data() + p->name_offset);
    }
}

// Print statistical information to stderr.  This is used for --stats.

void
Archive::print_stats()
{
  fprintf(stderr, _("%s: archive libraries: %u\n"),
          program_name, Archive::total_archives);
  fprintf(stderr, _("%s: total archive members: %u\n"),
          program_name, Archive::total_members);
  fprintf(stderr, _("%s: loaded archive members: %u\n"),
          program_name, Archive::total_members_loaded);
}

// Add_archive_symbols methods.

Add_archive_symbols::~Add_archive_symbols()
{
  if (this->this_blocker_ != NULL)
    delete this->this_blocker_;
  // next_blocker_ is deleted by the task associated with the next
  // input file.
}

// Return whether we can add the archive symbols.  We are blocked by
// this_blocker_.  We block next_blocker_.  We also lock the file.

Task_token*
Add_archive_symbols::is_runnable()
{
  if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
    return this->this_blocker_;
  return NULL;
}

void
Add_archive_symbols::locks(Task_locker* tl)
{
  tl->add(this, this->next_blocker_);
  tl->add(this, this->archive_->token());
}

void
Add_archive_symbols::run(Workqueue* workqueue)
{
  // For an incremental link, begin recording layout information.
  Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
  if (incremental_inputs != NULL)
    {
      unsigned int arg_serial = this->input_argument_->file().arg_serial();
      Script_info* script_info = this->input_argument_->script_info();
      incremental_inputs->report_archive_begin(this->archive_, arg_serial,
					       script_info);
    }

  bool added = this->archive_->add_symbols(this->symtab_, this->layout_,
					   this->input_objects_,
					   this->mapfile_);
  this->archive_->unlock_nested_archives();

  this->archive_->release();
  this->archive_->clear_uncached_views();

  if (!added)
    {
      // This archive holds object files which are incompatible with
      // our output file.
      Read_symbols::incompatible_warning(this->input_argument_,
					 this->archive_->input_file());
      Read_symbols::requeue(workqueue, this->input_objects_, this->symtab_,
			    this->layout_, this->dirpath_, this->dirindex_,
			    this->mapfile_, this->input_argument_,
			    this->input_group_, this->next_blocker_);
      delete this->archive_;
      return;
    }

  if (this->input_group_ != NULL)
    this->input_group_->add_archive(this->archive_);
  else
    {
      // For an incremental link, finish recording the layout information.
      if (incremental_inputs != NULL)
	incremental_inputs->report_archive_end(this->archive_);

      if (!parameters->options().has_plugins()
	  || this->archive_->input_file()->options().whole_archive())
	{
	  // We no longer need to know about this archive.
	  delete this->archive_;
	}
      else
	{
	  // The plugin interface may want to rescan this archive.
	  parameters->options().plugins()->save_archive(this->archive_);
	}

      this->archive_ = NULL;
    }
}

// Class Lib_group static variables.
unsigned int Lib_group::total_lib_groups;
unsigned int Lib_group::total_members;
unsigned int Lib_group::total_members_loaded;

Lib_group::Lib_group(const Input_file_lib* lib, Task* task)
  : Library_base(task), members_()
{
  this->members_.resize(lib->size());
}

const std::string&
Lib_group::do_filename() const
{
  std::string *filename = new std::string("/group/");
  return *filename;
}

// Select members from the lib group and add them to the link.  We walk
// through the members, and check if each one up should be included.
// If the object says it should be included, we do so.  We have to do
// this in a loop, since including one member may create new undefined
// symbols which may be satisfied by other members.

void
Lib_group::add_symbols(Symbol_table* symtab, Layout* layout,
                       Input_objects* input_objects)
{
  ++Lib_group::total_lib_groups;

  Lib_group::total_members += this->members_.size();

  bool added_new_object;
  do
    {
      added_new_object = false;
      unsigned int i = 0;
      while (i < this->members_.size())
	{
	  const Archive_member& member = this->members_[i];
	  Object* obj = member.obj_;
	  std::string why;

          // Skip files with no symbols. Plugin objects have
          // member.sd_ == NULL.
          if (obj != NULL
	      && (member.sd_ == NULL || member.sd_->symbol_names != NULL))
            {
	      Archive::Should_include t = obj->should_include_member(symtab,
								     layout,
								     member.sd_,
								     &why);

	      if (t != Archive::SHOULD_INCLUDE_YES)
		{
		  ++i;
		  continue;
		}

	      this->include_member(symtab, layout, input_objects, member);

	      added_new_object = true;
	    }
          else
            {
              if (member.sd_ != NULL)
		{
		  // The file must be locked in order to destroy the views
		  // associated with it.
		  gold_assert(obj != NULL);
		  obj->lock(this->task_);
		  delete member.sd_;
		  obj->unlock(this->task_);
		}
            }

	  this->members_[i] = this->members_.back();
	  this->members_.pop_back();
	}
    }
  while (added_new_object);
}

// Include a lib group member in the link.

void
Lib_group::include_member(Symbol_table* symtab, Layout* layout,
			  Input_objects* input_objects,
			  const Archive_member& member)
{
  ++Lib_group::total_members_loaded;

  Object* obj = member.obj_;
  gold_assert(obj != NULL);

  Pluginobj* pluginobj = obj->pluginobj();
  if (pluginobj != NULL)
    {
      pluginobj->add_symbols(symtab, NULL, layout);
      return;
    }

  Read_symbols_data* sd = member.sd_;
  gold_assert(sd != NULL);
  obj->lock(this->task_);
  if (input_objects->add_object(obj))
    {
      if (layout->incremental_inputs() != NULL)
	layout->incremental_inputs()->report_object(obj, member.arg_serial_,
						    this, NULL);
      obj->layout(symtab, layout, sd);
      obj->add_symbols(symtab, sd, layout);
    }
  delete sd;
  // Unlock the file for the next task.
  obj->unlock(this->task_);
}

// Iterate over all unused symbols, and call the visitor class V for each.

void
Lib_group::do_for_all_unused_symbols(Symbol_visitor_base* v) const
{
  // Files are removed from the members list when used, so all the
  // files remaining on the list are unused.
  for (std::vector<Archive_member>::const_iterator p = this->members_.begin();
       p != this->members_.end();
       ++p)
    {
      Object* obj = p->obj_;
      obj->for_all_global_symbols(p->sd_, v);
    }
}

// Print statistical information to stderr.  This is used for --stats.

void
Lib_group::print_stats()
{
  fprintf(stderr, _("%s: lib groups: %u\n"),
          program_name, Lib_group::total_lib_groups);
  fprintf(stderr, _("%s: total lib groups members: %u\n"),
          program_name, Lib_group::total_members);
  fprintf(stderr, _("%s: loaded lib groups members: %u\n"),
          program_name, Lib_group::total_members_loaded);
}

Task_token*
Add_lib_group_symbols::is_runnable()
{
  if (this->readsyms_blocker_ != NULL && this->readsyms_blocker_->is_blocked())
    return this->readsyms_blocker_;
  if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
    return this->this_blocker_;
  return NULL;
}

void
Add_lib_group_symbols::locks(Task_locker* tl)
{
  tl->add(this, this->next_blocker_);
}

void
Add_lib_group_symbols::run(Workqueue*)
{
  // For an incremental link, begin recording layout information.
  Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
  if (incremental_inputs != NULL)
    incremental_inputs->report_archive_begin(this->lib_, 0, NULL);

  this->lib_->add_symbols(this->symtab_, this->layout_, this->input_objects_);

  if (incremental_inputs != NULL)
    incremental_inputs->report_archive_end(this->lib_);
}

Add_lib_group_symbols::~Add_lib_group_symbols()
{
  if (this->this_blocker_ != NULL)
    delete this->this_blocker_;
  // next_blocker_ is deleted by the task associated with the next
  // input file.
}

} // End namespace gold.