contrib/binutils-2.24/gold/archive.cc

   1 // archive.cc -- archive support for gold
   2
   3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2013
   4 // Free Software Foundation, Inc.
   5 // Written by Ian Lance Taylor <iant@google.com>.
   6
   7 // This file is part of gold.
   8
   9 // This program is free software; you can redistribute it and/or modify
  10 // it under the terms of the GNU General Public License as published by
  11 // the Free Software Foundation; either version 3 of the License, or
  12 // (at your option) any later version.
  13
  14 // This program is distributed in the hope that it will be useful,
  15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 // GNU General Public License for more details.
  18
  19 // You should have received a copy of the GNU General Public License
  20 // along with this program; if not, write to the Free Software
  21 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  22 // MA 02110-1301, USA.
  23
  24 #include "gold.h"
  25
  26 #include <cerrno>
  27 #include <cstring>
  28 #include <climits>
  29 #include <vector>
  30 #include "libiberty.h"
  31 #include "filenames.h"
  32
  33 #include "elfcpp.h"
  34 #include "options.h"
  35 #include "mapfile.h"
  36 #include "fileread.h"
  37 #include "readsyms.h"
  38 #include "symtab.h"
  39 #include "object.h"
  40 #include "layout.h"
  41 #include "archive.h"
  42 #include "plugin.h"
  43 #include "incremental.h"
  44
  45 namespace gold
  46 {
  47
  48 // Library_base methods.
  49
  50 // Determine whether a definition of SYM_NAME should cause an archive
  51 // library member to be included in the link.  Returns SHOULD_INCLUDE_YES
  52 // if the symbol is referenced but not defined, SHOULD_INCLUDE_NO if the
  53 // symbol is already defined, and SHOULD_INCLUDE_UNKNOWN if the symbol is
  54 // neither referenced nor defined.
  55
  56 Library_base::Should_include
  57 Library_base::should_include_member(Symbol_table* symtab, Layout* layout,
  58                                     const char* sym_name, Symbol** symp,
  59                                     std::string* why, char** tmpbufp,
  60                                     size_t* tmpbuflen)
  61 {
  62   // In an object file, and therefore in an archive map, an
  63   // '@' in the name separates the symbol name from the
  64   // version name.  If there are two '@' characters, this is
  65   // the default version.
  66   char* tmpbuf = *tmpbufp;
  67   const char* ver = strchr(sym_name, '@');
  68   bool def = false;
  69   if (ver != NULL)
  70     {
  71       size_t symlen = ver - sym_name;
  72       if (symlen + 1 > *tmpbuflen)
  73         {
  74           tmpbuf = static_cast<char*>(xrealloc(tmpbuf, symlen + 1));
  75           *tmpbufp = tmpbuf;
  76           *tmpbuflen = symlen + 1;
  77         }
  78       memcpy(tmpbuf, sym_name, symlen);
  79       tmpbuf[symlen] = '\0';
  80       sym_name = tmpbuf;
  81
  82       ++ver;
  83       if (*ver == '@')
  84         {
  85           ++ver;
  86           def = true;
  87         }
  88     }
  89
  90   Symbol* sym = symtab->lookup(sym_name, ver);
  91   if (def
  92       && ver != NULL
  93       && (sym == NULL
  94           || !sym->is_undefined()
  95           || sym->binding() == elfcpp::STB_WEAK))
  96     sym = symtab->lookup(sym_name, NULL);
  97
  98   *symp = sym;
  99
 100   if (sym == NULL)
 101     {
 102       // Check whether the symbol was named in a -u option.
 103       if (parameters->options().is_undefined(sym_name))
 104         {
 105           *why = "-u ";
 106           *why += sym_name;
 107         }
 108       else if (parameters->options().is_export_dynamic_symbol(sym_name))
 109         {
 110           *why = "--export-dynamic-symbol ";
 111           *why += sym_name;
 112         }
 113       else if (layout->script_options()->is_referenced(sym_name))
 114         {
 115           size_t alc = 100 + strlen(sym_name);
 116           char* buf = new char[alc];
 117           snprintf(buf, alc, _("script or expression reference to %s"),
 118                    sym_name);
 119           *why = buf;
 120           delete[] buf;
 121         }
 122       else if (strcmp(sym_name, parameters->entry()) == 0)
 123         {
 124           *why = "entry symbol ";
 125           *why += sym_name;
 126         }
 127       else
 128         return Library_base::SHOULD_INCLUDE_UNKNOWN;
 129     }
 130   else if (!sym->is_undefined())
 131     return Library_base::SHOULD_INCLUDE_NO;
 132   // PR 12001: Do not include an archive when the undefined
 133   // symbol has actually been defined on the command line.
 134   else if (layout->script_options()->is_pending_assignment(sym_name))
 135     return Library_base::SHOULD_INCLUDE_NO;
 136   else if (sym->binding() == elfcpp::STB_WEAK)
 137     return Library_base::SHOULD_INCLUDE_UNKNOWN;
 138
 139   return Library_base::SHOULD_INCLUDE_YES;
 140 }
 141
 142 // The header of an entry in the archive.  This is all readable text,
 143 // padded with spaces where necessary.  If the contents of an archive
 144 // are all text file, the entire archive is readable.
 145
 146 struct Archive::Archive_header
 147 {
 148   // The entry name.
 149   char ar_name[16];
 150   // The file modification time.
 151   char ar_date[12];
 152   // The user's UID in decimal.
 153   char ar_uid[6];
 154   // The user's GID in decimal.
 155   char ar_gid[6];
 156   // The file mode in octal.
 157   char ar_mode[8];
 158   // The file size in decimal.
 159   char ar_size[10];
 160   // The final magic code.
 161   char ar_fmag[2];
 162 };
 163
 164 // Class Archive static variables.
 165 unsigned int Archive::total_archives;
 166 unsigned int Archive::total_members;
 167 unsigned int Archive::total_members_loaded;
 168
 169 // Archive methods.
 170
 171 const char Archive::armag[sarmag] =
 172 {
 173   '!', '<', 'a', 'r', 'c', 'h', '>', '\n'
 174 };
 175
 176 const char Archive::armagt[sarmag] =
 177 {
 178   '!', '<', 't', 'h', 'i', 'n', '>', '\n'
 179 };
 180
 181 const char Archive::arfmag[2] = { '`', '\n' };
 182
 183 Archive::Archive(const std::string& name, Input_file* input_file,
 184                  bool is_thin_archive, Dirsearch* dirpath, Task* task)
 185   : Library_base(task), name_(name), input_file_(input_file), armap_(),
 186     armap_names_(), extended_names_(), armap_checked_(), seen_offsets_(),
 187     members_(), is_thin_archive_(is_thin_archive), included_member_(false),
 188     nested_archives_(), dirpath_(dirpath), num_members_(0),
 189     included_all_members_(false)
 190 {
 191   this->no_export_ =
 192     parameters->options().check_excluded_libs(input_file->found_name());
 193 }
 194
 195 // Set up the archive: read the symbol map and the extended name
 196 // table.
 197
 198 void
 199 Archive::setup()
 200 {
 201   // We need to ignore empty archives.
 202   if (this->input_file_->file().filesize() == sarmag)
 203     return;
 204
 205   // The first member of the archive should be the symbol table.
 206   std::string armap_name;
 207   off_t header_size = this->read_header(sarmag, false, &armap_name, NULL);
 208   if (header_size == -1)
 209     return;
 210
 211   section_size_type armap_size = convert_to_section_size_type(header_size);
 212   off_t off = sarmag;
 213   if (armap_name.empty())
 214     {
 215       this->read_armap(sarmag + sizeof(Archive_header), armap_size);
 216       off = sarmag + sizeof(Archive_header) + armap_size;
 217     }
 218   else if (!this->input_file_->options().whole_archive())
 219     gold_error(_("%s: no archive symbol table (run ranlib)"),
 220                this->name().c_str());
 221
 222   // See if there is an extended name table.  We cache these views
 223   // because it is likely that we will want to read the following
 224   // header in the add_symbols routine.
 225   if ((off & 1) != 0)
 226     ++off;
 227   std::string xname;
 228   header_size = this->read_header(off, true, &xname, NULL);
 229   if (header_size == -1)
 230     return;
 231
 232   section_size_type extended_size = convert_to_section_size_type(header_size);
 233   if (xname == "/")
 234     {
 235       const unsigned char* p = this->get_view(off + sizeof(Archive_header),
 236                                               extended_size, false, true);
 237       const char* px = reinterpret_cast<const char*>(p);
 238       this->extended_names_.assign(px, extended_size);
 239     }
 240   bool preread_syms = (parameters->options().threads()
 241                        && parameters->options().preread_archive_symbols());
 242 #ifndef ENABLE_THREADS
 243   preread_syms = false;
 244 #else
 245   if (parameters->options().has_plugins())
 246     preread_syms = false;
 247 #endif
 248   if (preread_syms)
 249     this->read_all_symbols();
 250 }
 251
 252 // Unlock any nested archives.
 253
 254 void
 255 Archive::unlock_nested_archives()
 256 {
 257   for (Nested_archive_table::iterator p = this->nested_archives_.begin();
 258        p != this->nested_archives_.end();
 259        ++p)
 260     {
 261       p->second->unlock(this->task_);
 262     }
 263 }
 264
 265 // Read the archive symbol map.
 266
 267 void
 268 Archive::read_armap(off_t start, section_size_type size)
 269 {
 270   // To count the total number of archive members, we'll just count
 271   // the number of times the file offset changes.  Since most archives
 272   // group the symbols in the armap by object, this ought to give us
 273   // an accurate count.
 274   off_t last_seen_offset = -1;
 275
 276   // Read in the entire armap.
 277   const unsigned char* p = this->get_view(start, size, true, false);
 278
 279   // Numbers in the armap are always big-endian.
 280   const elfcpp::Elf_Word* pword = reinterpret_cast<const elfcpp::Elf_Word*>(p);
 281   unsigned int nsyms = elfcpp::Swap<32, true>::readval(pword);
 282   ++pword;
 283
 284   // Note that the addition is in units of sizeof(elfcpp::Elf_Word).
 285   const char* pnames = reinterpret_cast<const char*>(pword + nsyms);
 286   section_size_type names_size =
 287     reinterpret_cast<const char*>(p) + size - pnames;
 288   this->armap_names_.assign(pnames, names_size);
 289
 290   this->armap_.resize(nsyms);
 291
 292   section_offset_type name_offset = 0;
 293   for (unsigned int i = 0; i < nsyms; ++i)
 294     {
 295       this->armap_[i].name_offset = name_offset;
 296       this->armap_[i].file_offset = elfcpp::Swap<32, true>::readval(pword);
 297       name_offset += strlen(pnames + name_offset) + 1;
 298       ++pword;
 299       if (this->armap_[i].file_offset != last_seen_offset)
 300         {
 301           last_seen_offset = this->armap_[i].file_offset;
 302           ++this->num_members_;
 303         }
 304     }
 305
 306   if (static_cast<section_size_type>(name_offset) > names_size)
 307     gold_error(_("%s: bad archive symbol table names"),
 308                this->name().c_str());
 309
 310   // This array keeps track of which symbols are for archive elements
 311   // which we have already included in the link.
 312   this->armap_checked_.resize(nsyms);
 313 }
 314
 315 // Read the header of an archive member at OFF.  Fail if something
 316 // goes wrong.  Return the size of the member.  Set *PNAME to the name
 317 // of the member.
 318
 319 off_t
 320 Archive::read_header(off_t off, bool cache, std::string* pname,
 321                      off_t* nested_off)
 322 {
 323   const unsigned char* p = this->get_view(off, sizeof(Archive_header), true,
 324                                           cache);
 325   const Archive_header* hdr = reinterpret_cast<const Archive_header*>(p);
 326   return this->interpret_header(hdr, off,  pname, nested_off);
 327 }
 328
 329 // Interpret the header of HDR, the header of the archive member at
 330 // file offset OFF.  Return the size of the member, or -1 if something
 331 // has gone wrong.  Set *PNAME to the name of the member.
 332
 333 off_t
 334 Archive::interpret_header(const Archive_header* hdr, off_t off,
 335                           std::string* pname, off_t* nested_off) const
 336 {
 337   if (memcmp(hdr->ar_fmag, arfmag, sizeof arfmag) != 0)
 338     {
 339       gold_error(_("%s: malformed archive header at %zu"),
 340                  this->name().c_str(), static_cast<size_t>(off));
 341       return -1;
 342     }
 343
 344   const int size_string_size = sizeof hdr->ar_size;
 345   char size_string[size_string_size + 1];
 346   memcpy(size_string, hdr->ar_size, size_string_size);
 347   char* ps = size_string + size_string_size;
 348   while (ps[-1] == ' ')
 349     --ps;
 350   *ps = '\0';
 351
 352   errno = 0;
 353   char* end;
 354   off_t member_size = strtol(size_string, &end, 10);
 355   if (*end != '\0'
 356       || member_size < 0
 357       || (member_size == LONG_MAX && errno == ERANGE))
 358     {
 359       gold_error(_("%s: malformed archive header size at %zu"),
 360                  this->name().c_str(), static_cast<size_t>(off));
 361       return -1;
 362     }
 363
 364   if (hdr->ar_name[0] != '/')
 365     {
 366       const char* name_end = strchr(hdr->ar_name, '/');
 367       if (name_end == NULL
 368           || name_end - hdr->ar_name >= static_cast<int>(sizeof hdr->ar_name))
 369         {
 370           gold_error(_("%s: malformed archive header name at %zu"),
 371                      this->name().c_str(), static_cast<size_t>(off));
 372           return -1;
 373         }
 374       pname->assign(hdr->ar_name, name_end - hdr->ar_name);
 375       if (nested_off != NULL)
 376         *nested_off = 0;
 377     }
 378   else if (hdr->ar_name[1] == ' ')
 379     {
 380       // This is the symbol table.
 381       if (!pname->empty())
 382         pname->clear();
 383     }
 384   else if (hdr->ar_name[1] == '/')
 385     {
 386       // This is the extended name table.
 387       pname->assign(1, '/');
 388     }
 389   else
 390     {
 391       errno = 0;
 392       long x = strtol(hdr->ar_name + 1, &end, 10);
 393       long y = 0;
 394       if (*end == ':')
 395         y = strtol(end + 1, &end, 10);
 396       if (*end != ' '
 397           || x < 0
 398           || (x == LONG_MAX && errno == ERANGE)
 399           || static_cast<size_t>(x) >= this->extended_names_.size())
 400         {
 401           gold_error(_("%s: bad extended name index at %zu"),
 402                      this->name().c_str(), static_cast<size_t>(off));
 403           return -1;
 404         }
 405
 406       const char* name = this->extended_names_.data() + x;
 407       const char* name_end = strchr(name, '\n');
 408       if (static_cast<size_t>(name_end - name) > this->extended_names_.size()
 409           || name_end[-1] != '/')
 410         {
 411           gold_error(_("%s: bad extended name entry at header %zu"),
 412                      this->name().c_str(), static_cast<size_t>(off));
 413           return -1;
 414         }
 415       pname->assign(name, name_end - 1 - name);
 416       if (nested_off != NULL)
 417         *nested_off = y;
 418     }
 419
 420   return member_size;
 421 }
 422
 423 // An archive member iterator.
 424
 425 class Archive::const_iterator
 426 {
 427  public:
 428   // The header of an archive member.  This is what this iterator
 429   // points to.
 430   struct Header
 431   {
 432     // The name of the member.
 433     std::string name;
 434     // The file offset of the member.
 435     off_t off;
 436     // The file offset of a nested archive member.
 437     off_t nested_off;
 438     // The size of the member.
 439     off_t size;
 440   };
 441
 442   const_iterator(Archive* archive, off_t off)
 443     : archive_(archive), off_(off)
 444   { this->read_next_header(); }
 445
 446   const Header&
 447   operator*() const
 448   { return this->header_; }
 449
 450   const Header*
 451   operator->() const
 452   { return &this->header_; }
 453
 454   const_iterator&
 455   operator++()
 456   {
 457     if (this->off_ == this->archive_->file().filesize())
 458       return *this;
 459     this->off_ += sizeof(Archive_header);
 460     if (!this->archive_->is_thin_archive())
 461       this->off_ += this->header_.size;
 462     if ((this->off_ & 1) != 0)
 463       ++this->off_;
 464     this->read_next_header();
 465     return *this;
 466   }
 467
 468   const_iterator
 469   operator++(int)
 470   {
 471     const_iterator ret = *this;
 472     ++*this;
 473     return ret;
 474   }
 475
 476   bool
 477   operator==(const const_iterator p) const
 478   { return this->off_ == p->off; }
 479
 480   bool
 481   operator!=(const const_iterator p) const
 482   { return this->off_ != p->off; }
 483
 484  private:
 485   void
 486   read_next_header();
 487
 488   // The underlying archive.
 489   Archive* archive_;
 490   // The current offset in the file.
 491   off_t off_;
 492   // The current archive header.
 493   Header header_;
 494 };
 495
 496 // Read the next archive header.
 497
 498 void
 499 Archive::const_iterator::read_next_header()
 500 {
 501   off_t filesize = this->archive_->file().filesize();
 502   while (true)
 503     {
 504       if (filesize - this->off_ < static_cast<off_t>(sizeof(Archive_header)))
 505         {
 506           if (filesize != this->off_)
 507             {
 508               gold_error(_("%s: short archive header at %zu"),
 509                          this->archive_->filename().c_str(),
 510                          static_cast<size_t>(this->off_));
 511               this->off_ = filesize;
 512             }
 513           this->header_.off = filesize;
 514           return;
 515         }
 516
 517       unsigned char buf[sizeof(Archive_header)];
 518       this->archive_->file().read(this->off_, sizeof(Archive_header), buf);
 519
 520       const Archive_header* hdr = reinterpret_cast<const Archive_header*>(buf);
 521       off_t size = this->archive_->interpret_header(hdr, this->off_,
 522                                                     &this->header_.name,
 523                                                     &this->header_.nested_off);
 524       if (size == -1)
 525         {
 526           this->header_.off = filesize;
 527           return;
 528         }
 529
 530       this->header_.size = size;
 531       this->header_.off = this->off_;
 532
 533       // Skip special members.
 534       if (!this->header_.name.empty() && this->header_.name != "/")
 535         return;
 536
 537       this->off_ += sizeof(Archive_header) + this->header_.size;
 538       if ((this->off_ & 1) != 0)
 539         ++this->off_;
 540     }
 541 }
 542
 543 // Initial iterator.
 544
 545 Archive::const_iterator
 546 Archive::begin()
 547 {
 548   return Archive::const_iterator(this, sarmag);
 549 }
 550
 551 // Final iterator.
 552
 553 Archive::const_iterator
 554 Archive::end()
 555 {
 556   return Archive::const_iterator(this, this->input_file_->file().filesize());
 557 }
 558
 559 // Get the file and offset for an archive member, which may be an
 560 // external member of a thin archive.  Set *INPUT_FILE to the
 561 // file containing the actual member, *MEMOFF to the offset
 562 // within that file (0 if not a nested archive), and *MEMBER_NAME
 563 // to the name of the archive member.  Return TRUE on success.
 564
 565 bool
 566 Archive::get_file_and_offset(off_t off, Input_file** input_file, off_t* memoff,
 567                              off_t* memsize, std::string* member_name)
 568 {
 569   off_t nested_off;
 570
 571   *memsize = this->read_header(off, false, member_name, &nested_off);
 572   if (*memsize == -1)
 573     return false;
 574
 575   *input_file = this->input_file_;
 576   *memoff = off + static_cast<off_t>(sizeof(Archive_header));
 577
 578   if (!this->is_thin_archive_)
 579     return true;
 580
 581   // Adjust a relative pathname so that it is relative
 582   // to the directory containing the archive.
 583   if (!IS_ABSOLUTE_PATH(member_name->c_str()))
 584     {
 585       const char* arch_path = this->filename().c_str();
 586       const char* basename = lbasename(arch_path);
 587       if (basename > arch_path)
 588         member_name->replace(0, 0,
 589                              this->filename().substr(0, basename - arch_path));
 590     }
 591
 592   if (nested_off > 0)
 593     {
 594       // This is a member of a nested archive.  Open the containing
 595       // archive if we don't already have it open, then do a recursive
 596       // call to include the member from that archive.
 597       Archive* arch;
 598       Nested_archive_table::const_iterator p =
 599         this->nested_archives_.find(*member_name);
 600       if (p != this->nested_archives_.end())
 601         arch = p->second;
 602       else
 603         {
 604           Input_file_argument* input_file_arg =
 605             new Input_file_argument(member_name->c_str(),
 606                                     Input_file_argument::INPUT_FILE_TYPE_FILE,
 607                                     "", false, parameters->options());
 608           *input_file = new Input_file(input_file_arg);
 609           int dummy = 0;
 610           if (!(*input_file)->open(*this->dirpath_, this->task_, &dummy))
 611             return false;
 612           arch = new Archive(*member_name, *input_file, false, this->dirpath_,
 613                              this->task_);
 614           arch->setup();
 615           std::pair<Nested_archive_table::iterator, bool> ins =
 616             this->nested_archives_.insert(std::make_pair(*member_name, arch));
 617           gold_assert(ins.second);
 618         }
 619       return arch->get_file_and_offset(nested_off, input_file, memoff,
 620                                        memsize, member_name);
 621     }
 622
 623   // This is an external member of a thin archive.  Open the
 624   // file as a regular relocatable object file.
 625   Input_file_argument* input_file_arg =
 626       new Input_file_argument(member_name->c_str(),
 627                               Input_file_argument::INPUT_FILE_TYPE_FILE,
 628                               "", false, this->input_file_->options());
 629   *input_file = new Input_file(input_file_arg);
 630   int dummy = 0;
 631   if (!(*input_file)->open(*this->dirpath_, this->task_, &dummy))
 632     return false;
 633
 634   *memoff = 0;
 635   *memsize = (*input_file)->file().filesize();
 636   return true;
 637 }
 638
 639 // Return an ELF object for the member at offset OFF.  If
 640 // PUNCONFIGURED is not NULL, then if the ELF object has an
 641 // unsupported target type, set *PUNCONFIGURED to true and return
 642 // NULL.
 643
 644 Object*
 645 Archive::get_elf_object_for_member(off_t off, bool* punconfigured)
 646 {
 647   if (punconfigured != NULL)
 648     *punconfigured = false;
 649
 650   Input_file* input_file;
 651   off_t memoff;
 652   off_t memsize;
 653   std::string member_name;
 654   if (!this->get_file_and_offset(off, &input_file, &memoff, &memsize,
 655                                  &member_name))
 656     return NULL;
 657
 658   const unsigned char* ehdr;
 659   int read_size;
 660   Object *obj = NULL;
 661   bool is_elf_obj = false;
 662
 663   if (is_elf_object(input_file, memoff, &ehdr, &read_size))
 664     {
 665       obj = make_elf_object((std::string(this->input_file_->filename())
 666                              + "(" + member_name + ")"),
 667                             input_file, memoff, ehdr, read_size,
 668                             punconfigured);
 669       is_elf_obj = true;
 670     }
 671
 672   if (parameters->options().has_plugins())
 673     {
 674       Object* plugin_obj
 675         = parameters->options().plugins()->claim_file(input_file,
 676                                                       memoff,
 677                                                       memsize,
 678                                                       obj);
 679       if (plugin_obj != NULL)
 680         {
 681           // The input file was claimed by a plugin, and its symbols
 682           // have been provided by the plugin.
 683           // Delete its elf object.
 684           if (obj != NULL)
 685             delete obj;
 686           return plugin_obj;
 687         }
 688     }
 689
 690   if (!is_elf_obj)
 691     {
 692       gold_error(_("%s: member at %zu is not an ELF object"),
 693                  this->name().c_str(), static_cast<size_t>(off));
 694       return NULL;
 695     }
 696
 697   if (obj == NULL)
 698     return NULL;
 699   obj->set_no_export(this->no_export());
 700   return obj;
 701 }
 702
 703 // Read the symbols from all the archive members in the link.
 704
 705 void
 706 Archive::read_all_symbols()
 707 {
 708   for (Archive::const_iterator p = this->begin();
 709        p != this->end();
 710        ++p)
 711     this->read_symbols(p->off);
 712 }
 713
 714 // Read the symbols from an archive member in the link.  OFF is the file
 715 // offset of the member header.
 716
 717 void
 718 Archive::read_symbols(off_t off)
 719 {
 720   Object* obj = this->get_elf_object_for_member(off, NULL);
 721   if (obj == NULL)
 722     return;
 723
 724   Read_symbols_data* sd = new Read_symbols_data;
 725   obj->read_symbols(sd);
 726   Archive_member member(obj, sd);
 727   this->members_[off] = member;
 728 }
 729
 730 // Select members from the archive and add them to the link.  We walk
 731 // through the elements in the archive map, and look each one up in
 732 // the symbol table.  If it exists as a strong undefined symbol, we
 733 // pull in the corresponding element.  We have to do this in a loop,
 734 // since pulling in one element may create new undefined symbols which
 735 // may be satisfied by other objects in the archive.  Return true in
 736 // the normal case, false if the first member we tried to add from
 737 // this archive had an incompatible target.
 738
 739 bool
 740 Archive::add_symbols(Symbol_table* symtab, Layout* layout,
 741                      Input_objects* input_objects, Mapfile* mapfile)
 742 {
 743   ++Archive::total_archives;
 744
 745   if (this->input_file_->options().whole_archive())
 746     return this->include_all_members(symtab, layout, input_objects,
 747                                      mapfile);
 748
 749   Archive::total_members += this->num_members_;
 750
 751   input_objects->archive_start(this);
 752
 753   const size_t armap_size = this->armap_.size();
 754
 755   // This is a quick optimization, since we usually see many symbols
 756   // in a row with the same offset.  last_seen_offset holds the last
 757   // offset we saw that was present in the seen_offsets_ set.
 758   off_t last_seen_offset = -1;
 759
 760   // Track which symbols in the symbol table we've already found to be
 761   // defined.
 762
 763   char* tmpbuf = NULL;
 764   size_t tmpbuflen = 0;
 765   bool added_new_object;
 766   do
 767     {
 768       added_new_object = false;
 769       for (size_t i = 0; i < armap_size; ++i)
 770         {
 771           if (this->armap_checked_[i])
 772             continue;
 773           if (this->armap_[i].file_offset == last_seen_offset)
 774             {
 775               this->armap_checked_[i] = true;
 776               continue;
 777             }
 778           if (this->seen_offsets_.find(this->armap_[i].file_offset)
 779               != this->seen_offsets_.end())
 780             {
 781               this->armap_checked_[i] = true;
 782               last_seen_offset = this->armap_[i].file_offset;
 783               continue;
 784             }
 785
 786           const char* sym_name = (this->armap_names_.data()
 787                                   + this->armap_[i].name_offset);
 788
 789           Symbol* sym;
 790           std::string why;
 791           Archive::Should_include t =
 792             Archive::should_include_member(symtab, layout, sym_name, &sym,
 793                                            &why, &tmpbuf, &tmpbuflen);
 794
 795           if (t == Archive::SHOULD_INCLUDE_NO
 796               || t == Archive::SHOULD_INCLUDE_YES)
 797             this->armap_checked_[i] = true;
 798
 799           if (t != Archive::SHOULD_INCLUDE_YES)
 800             continue;
 801
 802           // We want to include this object in the link.
 803           last_seen_offset = this->armap_[i].file_offset;
 804           this->seen_offsets_.insert(last_seen_offset);
 805
 806           if (!this->include_member(symtab, layout, input_objects,
 807                                     last_seen_offset, mapfile, sym,
 808                                     why.c_str()))
 809             {
 810               if (tmpbuf != NULL)
 811                 free(tmpbuf);
 812               return false;
 813             }
 814
 815           added_new_object = true;
 816         }
 817     }
 818   while (added_new_object);
 819
 820   if (tmpbuf != NULL)
 821     free(tmpbuf);
 822
 823   input_objects->archive_stop(this);
 824
 825   return true;
 826 }
 827
 828 // Return whether the archive includes a member which defines the
 829 // symbol SYM.
 830
 831 bool
 832 Archive::defines_symbol(Symbol* sym) const
 833 {
 834   const char* symname = sym->name();
 835   size_t symname_len = strlen(symname);
 836   size_t armap_size = this->armap_.size();
 837   for (size_t i = 0; i < armap_size; ++i)
 838     {
 839       if (this->armap_checked_[i])
 840         continue;
 841       const char* archive_symname = (this->armap_names_.data()
 842                                      + this->armap_[i].name_offset);
 843       if (strncmp(archive_symname, symname, symname_len) != 0)
 844         continue;
 845       char c = archive_symname[symname_len];
 846       if (c == '\0' && sym->version() == NULL)
 847         return true;
 848       if (c == '@')
 849         {
 850           const char* ver = archive_symname + symname_len + 1;
 851           if (*ver == '@')
 852             {
 853               if (sym->version() == NULL)
 854                 return true;
 855               ++ver;
 856             }
 857           if (sym->version() != NULL && strcmp(sym->version(), ver) == 0)
 858             return true;
 859         }
 860     }
 861   return false;
 862 }
 863
 864 // Include all the archive members in the link.  This is for --whole-archive.
 865
 866 bool
 867 Archive::include_all_members(Symbol_table* symtab, Layout* layout,
 868                              Input_objects* input_objects, Mapfile* mapfile)
 869 {
 870   // Don't include the same archive twice.  This can happen if
 871   // --whole-archive is nested inside --start-group (PR gold/12163).
 872   if (this->included_all_members_)
 873     return true;
 874
 875   this->included_all_members_ = true;
 876
 877   input_objects->archive_start(this);
 878
 879   if (this->members_.size() > 0)
 880     {
 881       std::map<off_t, Archive_member>::const_iterator p;
 882       for (p = this->members_.begin();
 883            p != this->members_.end();
 884            ++p)
 885         {
 886           if (!this->include_member(symtab, layout, input_objects, p->first,
 887                                     mapfile, NULL, "--whole-archive"))
 888             return false;
 889           ++Archive::total_members;
 890         }
 891     }
 892   else
 893     {
 894       for (Archive::const_iterator p = this->begin();
 895            p != this->end();
 896            ++p)
 897         {
 898           if (!this->include_member(symtab, layout, input_objects, p->off,
 899                                     mapfile, NULL, "--whole-archive"))
 900             return false;
 901           ++Archive::total_members;
 902         }
 903     }
 904
 905   input_objects->archive_stop(this);
 906
 907   return true;
 908 }
 909
 910 // Return the number of members in the archive.  This is only used for
 911 // reports.
 912
 913 size_t
 914 Archive::count_members()
 915 {
 916   size_t ret = 0;
 917   for (Archive::const_iterator p = this->begin();
 918        p != this->end();
 919        ++p)
 920     ++ret;
 921   return ret;
 922 }
 923
 924 // Include an archive member in the link.  OFF is the file offset of
 925 // the member header.  WHY is the reason we are including this member.
 926 // Return true if we added the member or if we had an error, return
 927 // false if this was the first member we tried to add from this
 928 // archive and it had an incompatible format.
 929
 930 bool
 931 Archive::include_member(Symbol_table* symtab, Layout* layout,
 932                         Input_objects* input_objects, off_t off,
 933                         Mapfile* mapfile, Symbol* sym, const char* why)
 934 {
 935   ++Archive::total_members_loaded;
 936
 937   std::map<off_t, Archive_member>::const_iterator p = this->members_.find(off);
 938   if (p != this->members_.end())
 939     {
 940       Object* obj = p->second.obj_;
 941
 942       Read_symbols_data* sd = p->second.sd_;
 943       if (mapfile != NULL)
 944         mapfile->report_include_archive_member(obj->name(), sym, why);
 945       if (input_objects->add_object(obj))
 946         {
 947           obj->layout(symtab, layout, sd);
 948           obj->add_symbols(symtab, sd, layout);
 949           this->included_member_ = true;
 950         }
 951       delete sd;
 952       return true;
 953     }
 954
 955   // If this is the first object we are including from this archive,
 956   // and we searched for this archive, most likely because it was
 957   // found via a -l option, then if the target is incompatible we want
 958   // to move on to the next archive found in the search path.
 959   bool unconfigured = false;
 960   bool* punconfigured = NULL;
 961   if (!this->included_member_ && this->searched_for())
 962     punconfigured = &unconfigured;
 963
 964   Object* obj = this->get_elf_object_for_member(off, punconfigured);
 965   if (obj == NULL)
 966     {
 967       // Return false to search for another archive, true if we found
 968       // an error.
 969       return unconfigured ? false : true;
 970     }
 971
 972   if (mapfile != NULL)
 973     mapfile->report_include_archive_member(obj->name(), sym, why);
 974
 975   Pluginobj* pluginobj = obj->pluginobj();
 976   if (pluginobj != NULL)
 977     {
 978       pluginobj->add_symbols(symtab, NULL, layout);
 979       this->included_member_ = true;
 980       return true;
 981     }
 982
 983   if (!input_objects->add_object(obj))
 984     {
 985       // If this is an external member of a thin archive, unlock the
 986       // file.
 987       if (obj->offset() == 0)
 988         obj->unlock(this->task_);
 989       delete obj;
 990     }
 991   else
 992     {
 993       {
 994         if (layout->incremental_inputs() != NULL)
 995           layout->incremental_inputs()->report_object(obj, 0, this, NULL);
 996         Read_symbols_data sd;
 997         obj->read_symbols(&sd);
 998         obj->layout(symtab, layout, &sd);
 999         obj->add_symbols(symtab, &sd, layout);
1000       }
1001
1002       // If this is an external member of a thin archive, unlock the file
1003       // for the next task.
1004       if (obj->offset() == 0)
1005         obj->unlock(this->task_);
1006
1007       this->included_member_ = true;
1008     }
1009
1010   return true;
1011 }
1012
1013 // Iterate over all unused symbols, and call the visitor class V for each.
1014
1015 void
1016 Archive::do_for_all_unused_symbols(Symbol_visitor_base* v) const
1017 {
1018   for (std::vector<Armap_entry>::const_iterator p = this->armap_.begin();
1019        p != this->armap_.end();
1020        ++p)
1021     {
1022       if (this->seen_offsets_.find(p->file_offset)
1023           == this->seen_offsets_.end())
1024         v->visit(this->armap_names_.data() + p->name_offset);
1025     }
1026 }
1027
1028 // Print statistical information to stderr.  This is used for --stats.
1029
1030 void
1031 Archive::print_stats()
1032 {
1033   fprintf(stderr, _("%s: archive libraries: %u\n"),
1034           program_name, Archive::total_archives);
1035   fprintf(stderr, _("%s: total archive members: %u\n"),
1036           program_name, Archive::total_members);
1037   fprintf(stderr, _("%s: loaded archive members: %u\n"),
1038           program_name, Archive::total_members_loaded);
1039 }
1040
1041 // Add_archive_symbols methods.
1042
1043 Add_archive_symbols::~Add_archive_symbols()
1044 {
1045   if (this->this_blocker_ != NULL)
1046     delete this->this_blocker_;
1047   // next_blocker_ is deleted by the task associated with the next
1048   // input file.
1049 }
1050
1051 // Return whether we can add the archive symbols.  We are blocked by
1052 // this_blocker_.  We block next_blocker_.  We also lock the file.
1053
1054 Task_token*
1055 Add_archive_symbols::is_runnable()
1056 {
1057   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
1058     return this->this_blocker_;
1059   return NULL;
1060 }
1061
1062 void
1063 Add_archive_symbols::locks(Task_locker* tl)
1064 {
1065   tl->add(this, this->next_blocker_);
1066   tl->add(this, this->archive_->token());
1067 }
1068
1069 void
1070 Add_archive_symbols::run(Workqueue* workqueue)
1071 {
1072   // For an incremental link, begin recording layout information.
1073   Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
1074   if (incremental_inputs != NULL)
1075     {
1076       unsigned int arg_serial = this->input_argument_->file().arg_serial();
1077       Script_info* script_info = this->input_argument_->script_info();
1078       incremental_inputs->report_archive_begin(this->archive_, arg_serial,
1079                                                script_info);
1080     }
1081
1082   bool added = this->archive_->add_symbols(this->symtab_, this->layout_,
1083                                            this->input_objects_,
1084                                            this->mapfile_);
1085   this->archive_->unlock_nested_archives();
1086
1087   this->archive_->release();
1088   this->archive_->clear_uncached_views();
1089
1090   if (!added)
1091     {
1092       // This archive holds object files which are incompatible with
1093       // our output file.
1094       Read_symbols::incompatible_warning(this->input_argument_,
1095                                          this->archive_->input_file());
1096       Read_symbols::requeue(workqueue, this->input_objects_, this->symtab_,
1097                             this->layout_, this->dirpath_, this->dirindex_,
1098                             this->mapfile_, this->input_argument_,
1099                             this->input_group_, this->next_blocker_);
1100       delete this->archive_;
1101       return;
1102     }
1103
1104   if (this->input_group_ != NULL)
1105     this->input_group_->add_archive(this->archive_);
1106   else
1107     {
1108       // For an incremental link, finish recording the layout information.
1109       if (incremental_inputs != NULL)
1110         incremental_inputs->report_archive_end(this->archive_);
1111
1112       if (!parameters->options().has_plugins()
1113           || this->archive_->input_file()->options().whole_archive())
1114         {
1115           // We no longer need to know about this archive.
1116           delete this->archive_;
1117         }
1118       else
1119         {
1120           // The plugin interface may want to rescan this archive.
1121           parameters->options().plugins()->save_archive(this->archive_);
1122         }
1123
1124       this->archive_ = NULL;
1125     }
1126 }
1127
1128 // Class Lib_group static variables.
1129 unsigned int Lib_group::total_lib_groups;
1130 unsigned int Lib_group::total_members;
1131 unsigned int Lib_group::total_members_loaded;
1132
1133 Lib_group::Lib_group(const Input_file_lib* lib, Task* task)
1134   : Library_base(task), members_()
1135 {
1136   this->members_.resize(lib->size());
1137 }
1138
1139 const std::string&
1140 Lib_group::do_filename() const
1141 {
1142   std::string *filename = new std::string("/group/");
1143   return *filename;
1144 }
1145
1146 // Select members from the lib group and add them to the link.  We walk
1147 // through the members, and check if each one up should be included.
1148 // If the object says it should be included, we do so.  We have to do
1149 // this in a loop, since including one member may create new undefined
1150 // symbols which may be satisfied by other members.
1151
1152 void
1153 Lib_group::add_symbols(Symbol_table* symtab, Layout* layout,
1154                        Input_objects* input_objects)
1155 {
1156   ++Lib_group::total_lib_groups;
1157
1158   Lib_group::total_members += this->members_.size();
1159
1160   bool added_new_object;
1161   do
1162     {
1163       added_new_object = false;
1164       unsigned int i = 0;
1165       while (i < this->members_.size())
1166         {
1167           const Archive_member& member = this->members_[i];
1168           Object* obj = member.obj_;
1169           std::string why;
1170
1171           // Skip files with no symbols. Plugin objects have
1172           // member.sd_ == NULL.
1173           if (obj != NULL
1174               && (member.sd_ == NULL || member.sd_->symbol_names != NULL))
1175             {
1176               Archive::Should_include t = obj->should_include_member(symtab,
1177                                                                      layout,
1178                                                                      member.sd_,
1179                                                                      &why);
1180
1181               if (t != Archive::SHOULD_INCLUDE_YES)
1182                 {
1183                   ++i;
1184                   continue;
1185                 }
1186
1187               this->include_member(symtab, layout, input_objects, member);
1188
1189               added_new_object = true;
1190             }
1191           else
1192             {
1193               if (member.sd_ != NULL)
1194                 {
1195                   // The file must be locked in order to destroy the views
1196                   // associated with it.
1197                   gold_assert(obj != NULL);
1198                   obj->lock(this->task_);
1199                   delete member.sd_;
1200                   obj->unlock(this->task_);
1201                 }
1202             }
1203
1204           this->members_[i] = this->members_.back();
1205           this->members_.pop_back();
1206         }
1207     }
1208   while (added_new_object);
1209 }
1210
1211 // Include a lib group member in the link.
1212
1213 void
1214 Lib_group::include_member(Symbol_table* symtab, Layout* layout,
1215                           Input_objects* input_objects,
1216                           const Archive_member& member)
1217 {
1218   ++Lib_group::total_members_loaded;
1219
1220   Object* obj = member.obj_;
1221   gold_assert(obj != NULL);
1222
1223   Pluginobj* pluginobj = obj->pluginobj();
1224   if (pluginobj != NULL)
1225     {
1226       pluginobj->add_symbols(symtab, NULL, layout);
1227       return;
1228     }
1229
1230   Read_symbols_data* sd = member.sd_;
1231   gold_assert(sd != NULL);
1232   obj->lock(this->task_);
1233   if (input_objects->add_object(obj))
1234     {
1235       if (layout->incremental_inputs() != NULL)
1236         layout->incremental_inputs()->report_object(obj, member.arg_serial_,
1237                                                     this, NULL);
1238       obj->layout(symtab, layout, sd);
1239       obj->add_symbols(symtab, sd, layout);
1240     }
1241   delete sd;
1242   // Unlock the file for the next task.
1243   obj->unlock(this->task_);
1244 }
1245
1246 // Iterate over all unused symbols, and call the visitor class V for each.
1247
1248 void
1249 Lib_group::do_for_all_unused_symbols(Symbol_visitor_base* v) const
1250 {
1251   // Files are removed from the members list when used, so all the
1252   // files remaining on the list are unused.
1253   for (std::vector<Archive_member>::const_iterator p = this->members_.begin();
1254        p != this->members_.end();
1255        ++p)
1256     {
1257       Object* obj = p->obj_;
1258       obj->for_all_global_symbols(p->sd_, v);
1259     }
1260 }
1261
1262 // Print statistical information to stderr.  This is used for --stats.
1263
1264 void
1265 Lib_group::print_stats()
1266 {
1267   fprintf(stderr, _("%s: lib groups: %u\n"),
1268           program_name, Lib_group::total_lib_groups);
1269   fprintf(stderr, _("%s: total lib groups members: %u\n"),
1270           program_name, Lib_group::total_members);
1271   fprintf(stderr, _("%s: loaded lib groups members: %u\n"),
1272           program_name, Lib_group::total_members_loaded);
1273 }
1274
1275 Task_token*
1276 Add_lib_group_symbols::is_runnable()
1277 {
1278   if (this->readsyms_blocker_ != NULL && this->readsyms_blocker_->is_blocked())
1279     return this->readsyms_blocker_;
1280   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
1281     return this->this_blocker_;
1282   return NULL;
1283 }
1284
1285 void
1286 Add_lib_group_symbols::locks(Task_locker* tl)
1287 {
1288   tl->add(this, this->next_blocker_);
1289 }
1290
1291 void
1292 Add_lib_group_symbols::run(Workqueue*)
1293 {
1294   // For an incremental link, begin recording layout information.
1295   Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
1296   if (incremental_inputs != NULL)
1297     incremental_inputs->report_archive_begin(this->lib_, 0, NULL);
1298
1299   this->lib_->add_symbols(this->symtab_, this->layout_, this->input_objects_);
1300
1301   if (incremental_inputs != NULL)
1302     incremental_inputs->report_archive_end(this->lib_);
1303 }
1304
1305 Add_lib_group_symbols::~Add_lib_group_symbols()
1306 {
1307   if (this->this_blocker_ != NULL)
1308     delete this->this_blocker_;
1309   // next_blocker_ is deleted by the task associated with the next
1310   // input file.
1311 }
1312
1313 } // End namespace gold.