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