contrib/binutils-2.21/gold/archive.cc

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