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       if (!sym->is_undefined())
 103         return Library_base::SHOULD_INCLUDE_NO;
 104
 105       // PR 12001: Do not include an archive when the undefined
 106       // symbol has actually been defined on the command line.
 107       if (layout->script_options()->is_pending_assignment(sym_name))
 108         return Library_base::SHOULD_INCLUDE_NO;
 109
 110       // If the symbol is weak undefined, we still need to check
 111       // for other reasons (like a -u option).
 112       if (sym->binding() != elfcpp::STB_WEAK)
 113         return Library_base::SHOULD_INCLUDE_YES;
 114     }
 115
 116   // Check whether the symbol was named in a -u option.
 117   if (parameters->options().is_undefined(sym_name))
 118     {
 119       *why = "-u ";
 120       *why += sym_name;
 121       return Library_base::SHOULD_INCLUDE_YES;
 122     }
 123
 124   if (parameters->options().is_export_dynamic_symbol(sym_name))
 125     {
 126       *why = "--export-dynamic-symbol ";
 127       *why += sym_name;
 128       return Library_base::SHOULD_INCLUDE_YES;
 129     }
 130
 131   if (layout->script_options()->is_referenced(sym_name))
 132     {
 133       size_t alc = 100 + strlen(sym_name);
 134       char* buf = new char[alc];
 135       snprintf(buf, alc, _("script or expression reference to %s"),
 136                sym_name);
 137       *why = buf;
 138       delete[] buf;
 139       return Library_base::SHOULD_INCLUDE_YES;
 140     }
 141
 142   if (strcmp(sym_name, parameters->entry()) == 0)
 143     {
 144       *why = "entry symbol ";
 145       *why += sym_name;
 146       return Library_base::SHOULD_INCLUDE_YES;
 147     }
 148
 149   return Library_base::SHOULD_INCLUDE_UNKNOWN;
 150 }
 151
 152 // The header of an entry in the archive.  This is all readable text,
 153 // padded with spaces where necessary.  If the contents of an archive
 154 // are all text file, the entire archive is readable.
 155
 156 struct Archive::Archive_header
 157 {
 158   // The entry name.
 159   char ar_name[16];
 160   // The file modification time.
 161   char ar_date[12];
 162   // The user's UID in decimal.
 163   char ar_uid[6];
 164   // The user's GID in decimal.
 165   char ar_gid[6];
 166   // The file mode in octal.
 167   char ar_mode[8];
 168   // The file size in decimal.
 169   char ar_size[10];
 170   // The final magic code.
 171   char ar_fmag[2];
 172 };
 173
 174 // Class Archive static variables.
 175 unsigned int Archive::total_archives;
 176 unsigned int Archive::total_members;
 177 unsigned int Archive::total_members_loaded;
 178
 179 // Archive methods.
 180
 181 const char Archive::armag[sarmag] =
 182 {
 183   '!', '<', 'a', 'r', 'c', 'h', '>', '\n'
 184 };
 185
 186 const char Archive::armagt[sarmag] =
 187 {
 188   '!', '<', 't', 'h', 'i', 'n', '>', '\n'
 189 };
 190
 191 const char Archive::arfmag[2] = { '`', '\n' };
 192
 193 Archive::Archive(const std::string& name, Input_file* input_file,
 194                  bool is_thin_archive, Dirsearch* dirpath, Task* task)
 195   : Library_base(task), name_(name), input_file_(input_file), armap_(),
 196     armap_names_(), extended_names_(), armap_checked_(), seen_offsets_(),
 197     members_(), is_thin_archive_(is_thin_archive), included_member_(false),
 198     nested_archives_(), dirpath_(dirpath), num_members_(0),
 199     included_all_members_(false)
 200 {
 201   this->no_export_ =
 202     parameters->options().check_excluded_libs(input_file->found_name());
 203 }
 204
 205 // Set up the archive: read the symbol map and the extended name
 206 // table.
 207
 208 void
 209 Archive::setup()
 210 {
 211   // We need to ignore empty archives.
 212   if (this->input_file_->file().filesize() == sarmag)
 213     return;
 214
 215   // The first member of the archive should be the symbol table.
 216   std::string armap_name;
 217   off_t header_size = this->read_header(sarmag, false, &armap_name, NULL);
 218   if (header_size == -1)
 219     return;
 220
 221   section_size_type armap_size = convert_to_section_size_type(header_size);
 222   off_t off = sarmag;
 223   if (armap_name.empty())
 224     {
 225       this->read_armap(sarmag + sizeof(Archive_header), armap_size);
 226       off = sarmag + sizeof(Archive_header) + armap_size;
 227     }
 228   else if (!this->input_file_->options().whole_archive())
 229     gold_error(_("%s: no archive symbol table (run ranlib)"),
 230                this->name().c_str());
 231
 232   // See if there is an extended name table.  We cache these views
 233   // because it is likely that we will want to read the following
 234   // header in the add_symbols routine.
 235   if ((off & 1) != 0)
 236     ++off;
 237   std::string xname;
 238   header_size = this->read_header(off, true, &xname, NULL);
 239   if (header_size == -1)
 240     return;
 241
 242   section_size_type extended_size = convert_to_section_size_type(header_size);
 243   if (xname == "/")
 244     {
 245       const unsigned char* p = this->get_view(off + sizeof(Archive_header),
 246                                               extended_size, false, true);
 247       const char* px = reinterpret_cast<const char*>(p);
 248       this->extended_names_.assign(px, extended_size);
 249     }
 250   bool preread_syms = (parameters->options().threads()
 251                        && parameters->options().preread_archive_symbols());
 252 #ifndef ENABLE_THREADS
 253   preread_syms = false;
 254 #else
 255   if (parameters->options().has_plugins())
 256     preread_syms = false;
 257 #endif
 258   if (preread_syms)
 259     this->read_all_symbols();
 260 }
 261
 262 // Unlock any nested archives.
 263
 264 void
 265 Archive::unlock_nested_archives()
 266 {
 267   for (Nested_archive_table::iterator p = this->nested_archives_.begin();
 268        p != this->nested_archives_.end();
 269        ++p)
 270     {
 271       p->second->unlock(this->task_);
 272     }
 273 }
 274
 275 // Read the archive symbol map.
 276
 277 void
 278 Archive::read_armap(off_t start, section_size_type size)
 279 {
 280   // To count the total number of archive members, we'll just count
 281   // the number of times the file offset changes.  Since most archives
 282   // group the symbols in the armap by object, this ought to give us
 283   // an accurate count.
 284   off_t last_seen_offset = -1;
 285
 286   // Read in the entire armap.
 287   const unsigned char* p = this->get_view(start, size, true, false);
 288
 289   // Numbers in the armap are always big-endian.
 290   const elfcpp::Elf_Word* pword = reinterpret_cast<const elfcpp::Elf_Word*>(p);
 291   unsigned int nsyms = elfcpp::Swap<32, true>::readval(pword);
 292   ++pword;
 293
 294   // Note that the addition is in units of sizeof(elfcpp::Elf_Word).
 295   const char* pnames = reinterpret_cast<const char*>(pword + nsyms);
 296   section_size_type names_size =
 297     reinterpret_cast<const char*>(p) + size - pnames;
 298   this->armap_names_.assign(pnames, names_size);
 299
 300   this->armap_.resize(nsyms);
 301
 302   section_offset_type name_offset = 0;
 303   for (unsigned int i = 0; i < nsyms; ++i)
 304     {
 305       this->armap_[i].name_offset = name_offset;
 306       this->armap_[i].file_offset = elfcpp::Swap<32, true>::readval(pword);
 307       name_offset += strlen(pnames + name_offset) + 1;
 308       ++pword;
 309       if (this->armap_[i].file_offset != last_seen_offset)
 310         {
 311           last_seen_offset = this->armap_[i].file_offset;
 312           ++this->num_members_;
 313         }
 314     }
 315
 316   if (static_cast<section_size_type>(name_offset) > names_size)
 317     gold_error(_("%s: bad archive symbol table names"),
 318                this->name().c_str());
 319
 320   // This array keeps track of which symbols are for archive elements
 321   // which we have already included in the link.
 322   this->armap_checked_.resize(nsyms);
 323 }
 324
 325 // Read the header of an archive member at OFF.  Fail if something
 326 // goes wrong.  Return the size of the member.  Set *PNAME to the name
 327 // of the member.
 328
 329 off_t
 330 Archive::read_header(off_t off, bool cache, std::string* pname,
 331                      off_t* nested_off)
 332 {
 333   const unsigned char* p = this->get_view(off, sizeof(Archive_header), true,
 334                                           cache);
 335   const Archive_header* hdr = reinterpret_cast<const Archive_header*>(p);
 336   return this->interpret_header(hdr, off,  pname, nested_off);
 337 }
 338
 339 // Interpret the header of HDR, the header of the archive member at
 340 // file offset OFF.  Return the size of the member, or -1 if something
 341 // has gone wrong.  Set *PNAME to the name of the member.
 342
 343 off_t
 344 Archive::interpret_header(const Archive_header* hdr, off_t off,
 345                           std::string* pname, off_t* nested_off) const
 346 {
 347   if (memcmp(hdr->ar_fmag, arfmag, sizeof arfmag) != 0)
 348     {
 349       gold_error(_("%s: malformed archive header at %zu"),
 350                  this->name().c_str(), static_cast<size_t>(off));
 351       return -1;
 352     }
 353
 354   const int size_string_size = sizeof hdr->ar_size;
 355   char size_string[size_string_size + 1];
 356   memcpy(size_string, hdr->ar_size, size_string_size);
 357   char* ps = size_string + size_string_size;
 358   while (ps[-1] == ' ')
 359     --ps;
 360   *ps = '\0';
 361
 362   errno = 0;
 363   char* end;
 364   off_t member_size = strtol(size_string, &end, 10);
 365   if (*end != '\0'
 366       || member_size < 0
 367       || (member_size == LONG_MAX && errno == ERANGE))
 368     {
 369       gold_error(_("%s: malformed archive header size at %zu"),
 370                  this->name().c_str(), static_cast<size_t>(off));
 371       return -1;
 372     }
 373
 374   if (hdr->ar_name[0] != '/')
 375     {
 376       const char* name_end = strchr(hdr->ar_name, '/');
 377       if (name_end == NULL
 378           || name_end - hdr->ar_name >= static_cast<int>(sizeof hdr->ar_name))
 379         {
 380           gold_error(_("%s: malformed archive header name at %zu"),
 381                      this->name().c_str(), static_cast<size_t>(off));
 382           return -1;
 383         }
 384       pname->assign(hdr->ar_name, name_end - hdr->ar_name);
 385       if (nested_off != NULL)
 386         *nested_off = 0;
 387     }
 388   else if (hdr->ar_name[1] == ' ')
 389     {
 390       // This is the symbol table.
 391       if (!pname->empty())
 392         pname->clear();
 393     }
 394   else if (hdr->ar_name[1] == '/')
 395     {
 396       // This is the extended name table.
 397       pname->assign(1, '/');
 398     }
 399   else
 400     {
 401       errno = 0;
 402       long x = strtol(hdr->ar_name + 1, &end, 10);
 403       long y = 0;
 404       if (*end == ':')
 405         y = strtol(end + 1, &end, 10);
 406       if (*end != ' '
 407           || x < 0
 408           || (x == LONG_MAX && errno == ERANGE)
 409           || static_cast<size_t>(x) >= this->extended_names_.size())
 410         {
 411           gold_error(_("%s: bad extended name index at %zu"),
 412                      this->name().c_str(), static_cast<size_t>(off));
 413           return -1;
 414         }
 415
 416       const char* name = this->extended_names_.data() + x;
 417       const char* name_end = strchr(name, '\n');
 418       if (static_cast<size_t>(name_end - name) > this->extended_names_.size()
 419           || name_end[-1] != '/')
 420         {
 421           gold_error(_("%s: bad extended name entry at header %zu"),
 422                      this->name().c_str(), static_cast<size_t>(off));
 423           return -1;
 424         }
 425       pname->assign(name, name_end - 1 - name);
 426       if (nested_off != NULL)
 427         *nested_off = y;
 428     }
 429
 430   return member_size;
 431 }
 432
 433 // An archive member iterator.
 434
 435 class Archive::const_iterator
 436 {
 437  public:
 438   // The header of an archive member.  This is what this iterator
 439   // points to.
 440   struct Header
 441   {
 442     // The name of the member.
 443     std::string name;
 444     // The file offset of the member.
 445     off_t off;
 446     // The file offset of a nested archive member.
 447     off_t nested_off;
 448     // The size of the member.
 449     off_t size;
 450   };
 451
 452   const_iterator(Archive* archive, off_t off)
 453     : archive_(archive), off_(off)
 454   { this->read_next_header(); }
 455
 456   const Header&
 457   operator*() const
 458   { return this->header_; }
 459
 460   const Header*
 461   operator->() const
 462   { return &this->header_; }
 463
 464   const_iterator&
 465   operator++()
 466   {
 467     if (this->off_ == this->archive_->file().filesize())
 468       return *this;
 469     this->off_ += sizeof(Archive_header);
 470     if (!this->archive_->is_thin_archive())
 471       this->off_ += this->header_.size;
 472     if ((this->off_ & 1) != 0)
 473       ++this->off_;
 474     this->read_next_header();
 475     return *this;
 476   }
 477
 478   const_iterator
 479   operator++(int)
 480   {
 481     const_iterator ret = *this;
 482     ++*this;
 483     return ret;
 484   }
 485
 486   bool
 487   operator==(const const_iterator p) const
 488   { return this->off_ == p->off; }
 489
 490   bool
 491   operator!=(const const_iterator p) const
 492   { return this->off_ != p->off; }
 493
 494  private:
 495   void
 496   read_next_header();
 497
 498   // The underlying archive.
 499   Archive* archive_;
 500   // The current offset in the file.
 501   off_t off_;
 502   // The current archive header.
 503   Header header_;
 504 };
 505
 506 // Read the next archive header.
 507
 508 void
 509 Archive::const_iterator::read_next_header()
 510 {
 511   off_t filesize = this->archive_->file().filesize();
 512   while (true)
 513     {
 514       if (filesize - this->off_ < static_cast<off_t>(sizeof(Archive_header)))
 515         {
 516           if (filesize != this->off_)
 517             {
 518               gold_error(_("%s: short archive header at %zu"),
 519                          this->archive_->filename().c_str(),
 520                          static_cast<size_t>(this->off_));
 521               this->off_ = filesize;
 522             }
 523           this->header_.off = filesize;
 524           return;
 525         }
 526
 527       unsigned char buf[sizeof(Archive_header)];
 528       this->archive_->file().read(this->off_, sizeof(Archive_header), buf);
 529
 530       const Archive_header* hdr = reinterpret_cast<const Archive_header*>(buf);
 531       off_t size = this->archive_->interpret_header(hdr, this->off_,
 532                                                     &this->header_.name,
 533                                                     &this->header_.nested_off);
 534       if (size == -1)
 535         {
 536           this->header_.off = filesize;
 537           return;
 538         }
 539
 540       this->header_.size = size;
 541       this->header_.off = this->off_;
 542
 543       // Skip special members.
 544       if (!this->header_.name.empty() && this->header_.name != "/")
 545         return;
 546
 547       this->off_ += sizeof(Archive_header) + this->header_.size;
 548       if ((this->off_ & 1) != 0)
 549         ++this->off_;
 550     }
 551 }
 552
 553 // Initial iterator.
 554
 555 Archive::const_iterator
 556 Archive::begin()
 557 {
 558   return Archive::const_iterator(this, sarmag);
 559 }
 560
 561 // Final iterator.
 562
 563 Archive::const_iterator
 564 Archive::end()
 565 {
 566   return Archive::const_iterator(this, this->input_file_->file().filesize());
 567 }
 568
 569 // Get the file and offset for an archive member, which may be an
 570 // external member of a thin archive.  Set *INPUT_FILE to the
 571 // file containing the actual member, *MEMOFF to the offset
 572 // within that file (0 if not a nested archive), and *MEMBER_NAME
 573 // to the name of the archive member.  Return TRUE on success.
 574
 575 bool
 576 Archive::get_file_and_offset(off_t off, Input_file** input_file, off_t* memoff,
 577                              off_t* memsize, std::string* member_name)
 578 {
 579   off_t nested_off;
 580
 581   *memsize = this->read_header(off, false, member_name, &nested_off);
 582   if (*memsize == -1)
 583     return false;
 584
 585   *input_file = this->input_file_;
 586   *memoff = off + static_cast<off_t>(sizeof(Archive_header));
 587
 588   if (!this->is_thin_archive_)
 589     return true;
 590
 591   // Adjust a relative pathname so that it is relative
 592   // to the directory containing the archive.
 593   if (!IS_ABSOLUTE_PATH(member_name->c_str()))
 594     {
 595       const char* arch_path = this->filename().c_str();
 596       const char* basename = lbasename(arch_path);
 597       if (basename > arch_path)
 598         member_name->replace(0, 0,
 599                              this->filename().substr(0, basename - arch_path));
 600     }
 601
 602   if (nested_off > 0)
 603     {
 604       // This is a member of a nested archive.  Open the containing
 605       // archive if we don't already have it open, then do a recursive
 606       // call to include the member from that archive.
 607       Archive* arch;
 608       Nested_archive_table::const_iterator p =
 609         this->nested_archives_.find(*member_name);
 610       if (p != this->nested_archives_.end())
 611         arch = p->second;
 612       else
 613         {
 614           Input_file_argument* input_file_arg =
 615             new Input_file_argument(member_name->c_str(),
 616                                     Input_file_argument::INPUT_FILE_TYPE_FILE,
 617                                     "", false, parameters->options());
 618           *input_file = new Input_file(input_file_arg);
 619           int dummy = 0;
 620           if (!(*input_file)->open(*this->dirpath_, this->task_, &dummy))
 621             return false;
 622           arch = new Archive(*member_name, *input_file, false, this->dirpath_,
 623                              this->task_);
 624           arch->setup();
 625           std::pair<Nested_archive_table::iterator, bool> ins =
 626             this->nested_archives_.insert(std::make_pair(*member_name, arch));
 627           gold_assert(ins.second);
 628         }
 629       return arch->get_file_and_offset(nested_off, input_file, memoff,
 630                                        memsize, member_name);
 631     }
 632
 633   // This is an external member of a thin archive.  Open the
 634   // file as a regular relocatable object file.
 635   Input_file_argument* input_file_arg =
 636       new Input_file_argument(member_name->c_str(),
 637                               Input_file_argument::INPUT_FILE_TYPE_FILE,
 638                               "", false, this->input_file_->options());
 639   *input_file = new Input_file(input_file_arg);
 640   int dummy = 0;
 641   if (!(*input_file)->open(*this->dirpath_, this->task_, &dummy))
 642     return false;
 643
 644   *memoff = 0;
 645   *memsize = (*input_file)->file().filesize();
 646   return true;
 647 }
 648
 649 // Return an ELF object for the member at offset OFF.  If
 650 // PUNCONFIGURED is not NULL, then if the ELF object has an
 651 // unsupported target type, set *PUNCONFIGURED to true and return
 652 // NULL.
 653
 654 Object*
 655 Archive::get_elf_object_for_member(off_t off, bool* punconfigured)
 656 {
 657   if (punconfigured != NULL)
 658     *punconfigured = false;
 659
 660   Input_file* input_file;
 661   off_t memoff;
 662   off_t memsize;
 663   std::string member_name;
 664   if (!this->get_file_and_offset(off, &input_file, &memoff, &memsize,
 665                                  &member_name))
 666     return NULL;
 667
 668   const unsigned char* ehdr;
 669   int read_size;
 670   Object *obj = NULL;
 671   bool is_elf_obj = false;
 672
 673   if (is_elf_object(input_file, memoff, &ehdr, &read_size))
 674     {
 675       obj = make_elf_object((std::string(this->input_file_->filename())
 676                              + "(" + member_name + ")"),
 677                             input_file, memoff, ehdr, read_size,
 678                             punconfigured);
 679       is_elf_obj = true;
 680     }
 681
 682   if (parameters->options().has_plugins())
 683     {
 684       Object* plugin_obj
 685         = parameters->options().plugins()->claim_file(input_file,
 686                                                       memoff,
 687                                                       memsize,
 688                                                       obj);
 689       if (plugin_obj != NULL)
 690         {
 691           // The input file was claimed by a plugin, and its symbols
 692           // have been provided by the plugin.
 693           // Delete its elf object.
 694           if (obj != NULL)
 695             delete obj;
 696           return plugin_obj;
 697         }
 698     }
 699
 700   if (!is_elf_obj)
 701     {
 702       gold_error(_("%s: member at %zu is not an ELF object"),
 703                  this->name().c_str(), static_cast<size_t>(off));
 704       return NULL;
 705     }
 706
 707   if (obj == NULL)
 708     return NULL;
 709   obj->set_no_export(this->no_export());
 710   return obj;
 711 }
 712
 713 // Read the symbols from all the archive members in the link.
 714
 715 void
 716 Archive::read_all_symbols()
 717 {
 718   for (Archive::const_iterator p = this->begin();
 719        p != this->end();
 720        ++p)
 721     this->read_symbols(p->off);
 722 }
 723
 724 // Read the symbols from an archive member in the link.  OFF is the file
 725 // offset of the member header.
 726
 727 void
 728 Archive::read_symbols(off_t off)
 729 {
 730   Object* obj = this->get_elf_object_for_member(off, NULL);
 731   if (obj == NULL)
 732     return;
 733
 734   Read_symbols_data* sd = new Read_symbols_data;
 735   obj->read_symbols(sd);
 736   Archive_member member(obj, sd);
 737   this->members_[off] = member;
 738 }
 739
 740 // Select members from the archive and add them to the link.  We walk
 741 // through the elements in the archive map, and look each one up in
 742 // the symbol table.  If it exists as a strong undefined symbol, we
 743 // pull in the corresponding element.  We have to do this in a loop,
 744 // since pulling in one element may create new undefined symbols which
 745 // may be satisfied by other objects in the archive.  Return true in
 746 // the normal case, false if the first member we tried to add from
 747 // this archive had an incompatible target.
 748
 749 bool
 750 Archive::add_symbols(Symbol_table* symtab, Layout* layout,
 751                      Input_objects* input_objects, Mapfile* mapfile)
 752 {
 753   ++Archive::total_archives;
 754
 755   if (this->input_file_->options().whole_archive())
 756     return this->include_all_members(symtab, layout, input_objects,
 757                                      mapfile);
 758
 759   Archive::total_members += this->num_members_;
 760
 761   input_objects->archive_start(this);
 762
 763   const size_t armap_size = this->armap_.size();
 764
 765   // This is a quick optimization, since we usually see many symbols
 766   // in a row with the same offset.  last_seen_offset holds the last
 767   // offset we saw that was present in the seen_offsets_ set.
 768   off_t last_seen_offset = -1;
 769
 770   // Track which symbols in the symbol table we've already found to be
 771   // defined.
 772
 773   char* tmpbuf = NULL;
 774   size_t tmpbuflen = 0;
 775   bool added_new_object;
 776   do
 777     {
 778       added_new_object = false;
 779       for (size_t i = 0; i < armap_size; ++i)
 780         {
 781           if (this->armap_checked_[i])
 782             continue;
 783           if (this->armap_[i].file_offset == last_seen_offset)
 784             {
 785               this->armap_checked_[i] = true;
 786               continue;
 787             }
 788           if (this->seen_offsets_.find(this->armap_[i].file_offset)
 789               != this->seen_offsets_.end())
 790             {
 791               this->armap_checked_[i] = true;
 792               last_seen_offset = this->armap_[i].file_offset;
 793               continue;
 794             }
 795
 796           const char* sym_name = (this->armap_names_.data()
 797                                   + this->armap_[i].name_offset);
 798
 799           Symbol* sym;
 800           std::string why;
 801           Archive::Should_include t =
 802             Archive::should_include_member(symtab, layout, sym_name, &sym,
 803                                            &why, &tmpbuf, &tmpbuflen);
 804
 805           if (t == Archive::SHOULD_INCLUDE_NO
 806               || t == Archive::SHOULD_INCLUDE_YES)
 807             this->armap_checked_[i] = true;
 808
 809           if (t != Archive::SHOULD_INCLUDE_YES)
 810             continue;
 811
 812           // We want to include this object in the link.
 813           last_seen_offset = this->armap_[i].file_offset;
 814           this->seen_offsets_.insert(last_seen_offset);
 815
 816           if (!this->include_member(symtab, layout, input_objects,
 817                                     last_seen_offset, mapfile, sym,
 818                                     why.c_str()))
 819             {
 820               if (tmpbuf != NULL)
 821                 free(tmpbuf);
 822               return false;
 823             }
 824
 825           added_new_object = true;
 826         }
 827     }
 828   while (added_new_object);
 829
 830   if (tmpbuf != NULL)
 831     free(tmpbuf);
 832
 833   input_objects->archive_stop(this);
 834
 835   return true;
 836 }
 837
 838 // Return whether the archive includes a member which defines the
 839 // symbol SYM.
 840
 841 bool
 842 Archive::defines_symbol(Symbol* sym) const
 843 {
 844   const char* symname = sym->name();
 845   size_t symname_len = strlen(symname);
 846   size_t armap_size = this->armap_.size();
 847   for (size_t i = 0; i < armap_size; ++i)
 848     {
 849       if (this->armap_checked_[i])
 850         continue;
 851       const char* archive_symname = (this->armap_names_.data()
 852                                      + this->armap_[i].name_offset);
 853       if (strncmp(archive_symname, symname, symname_len) != 0)
 854         continue;
 855       char c = archive_symname[symname_len];
 856       if (c == '\0' && sym->version() == NULL)
 857         return true;
 858       if (c == '@')
 859         {
 860           const char* ver = archive_symname + symname_len + 1;
 861           if (*ver == '@')
 862             {
 863               if (sym->version() == NULL)
 864                 return true;
 865               ++ver;
 866             }
 867           if (sym->version() != NULL && strcmp(sym->version(), ver) == 0)
 868             return true;
 869         }
 870     }
 871   return false;
 872 }
 873
 874 // Include all the archive members in the link.  This is for --whole-archive.
 875
 876 bool
 877 Archive::include_all_members(Symbol_table* symtab, Layout* layout,
 878                              Input_objects* input_objects, Mapfile* mapfile)
 879 {
 880   // Don't include the same archive twice.  This can happen if
 881   // --whole-archive is nested inside --start-group (PR gold/12163).
 882   if (this->included_all_members_)
 883     return true;
 884
 885   this->included_all_members_ = true;
 886
 887   input_objects->archive_start(this);
 888
 889   if (this->members_.size() > 0)
 890     {
 891       std::map<off_t, Archive_member>::const_iterator p;
 892       for (p = this->members_.begin();
 893            p != this->members_.end();
 894            ++p)
 895         {
 896           if (!this->include_member(symtab, layout, input_objects, p->first,
 897                                     mapfile, NULL, "--whole-archive"))
 898             return false;
 899           ++Archive::total_members;
 900         }
 901     }
 902   else
 903     {
 904       for (Archive::const_iterator p = this->begin();
 905            p != this->end();
 906            ++p)
 907         {
 908           if (!this->include_member(symtab, layout, input_objects, p->off,
 909                                     mapfile, NULL, "--whole-archive"))
 910             return false;
 911           ++Archive::total_members;
 912         }
 913     }
 914
 915   input_objects->archive_stop(this);
 916
 917   return true;
 918 }
 919
 920 // Return the number of members in the archive.  This is only used for
 921 // reports.
 922
 923 size_t
 924 Archive::count_members()
 925 {
 926   size_t ret = 0;
 927   for (Archive::const_iterator p = this->begin();
 928        p != this->end();
 929        ++p)
 930     ++ret;
 931   return ret;
 932 }
 933
 934 // Include an archive member in the link.  OFF is the file offset of
 935 // the member header.  WHY is the reason we are including this member.
 936 // Return true if we added the member or if we had an error, return
 937 // false if this was the first member we tried to add from this
 938 // archive and it had an incompatible format.
 939
 940 bool
 941 Archive::include_member(Symbol_table* symtab, Layout* layout,
 942                         Input_objects* input_objects, off_t off,
 943                         Mapfile* mapfile, Symbol* sym, const char* why)
 944 {
 945   ++Archive::total_members_loaded;
 946
 947   std::map<off_t, Archive_member>::const_iterator p = this->members_.find(off);
 948   if (p != this->members_.end())
 949     {
 950       Object* obj = p->second.obj_;
 951
 952       Read_symbols_data* sd = p->second.sd_;
 953       if (mapfile != NULL)
 954         mapfile->report_include_archive_member(obj->name(), sym, why);
 955       if (input_objects->add_object(obj))
 956         {
 957           obj->layout(symtab, layout, sd);
 958           obj->add_symbols(symtab, sd, layout);
 959           this->included_member_ = true;
 960         }
 961       delete sd;
 962       return true;
 963     }
 964
 965   // If this is the first object we are including from this archive,
 966   // and we searched for this archive, most likely because it was
 967   // found via a -l option, then if the target is incompatible we want
 968   // to move on to the next archive found in the search path.
 969   bool unconfigured = false;
 970   bool* punconfigured = NULL;
 971   if (!this->included_member_ && this->searched_for())
 972     punconfigured = &unconfigured;
 973
 974   Object* obj = this->get_elf_object_for_member(off, punconfigured);
 975   if (obj == NULL)
 976     {
 977       // Return false to search for another archive, true if we found
 978       // an error.
 979       return unconfigured ? false : true;
 980     }
 981
 982   if (mapfile != NULL)
 983     mapfile->report_include_archive_member(obj->name(), sym, why);
 984
 985   Pluginobj* pluginobj = obj->pluginobj();
 986   if (pluginobj != NULL)
 987     {
 988       pluginobj->add_symbols(symtab, NULL, layout);
 989       this->included_member_ = true;
 990       return true;
 991     }
 992
 993   if (!input_objects->add_object(obj))
 994     {
 995       // If this is an external member of a thin archive, unlock the
 996       // file.
 997       if (obj->offset() == 0)
 998         obj->unlock(this->task_);
 999       delete obj;
1000     }
1001   else
1002     {
1003       {
1004         if (layout->incremental_inputs() != NULL)
1005           layout->incremental_inputs()->report_object(obj, 0, this, NULL);
1006         Read_symbols_data sd;
1007         obj->read_symbols(&sd);
1008         obj->layout(symtab, layout, &sd);
1009         obj->add_symbols(symtab, &sd, layout);
1010       }
1011
1012       // If this is an external member of a thin archive, unlock the file
1013       // for the next task.
1014       if (obj->offset() == 0)
1015         obj->unlock(this->task_);
1016
1017       this->included_member_ = true;
1018     }
1019
1020   return true;
1021 }
1022
1023 // Iterate over all unused symbols, and call the visitor class V for each.
1024
1025 void
1026 Archive::do_for_all_unused_symbols(Symbol_visitor_base* v) const
1027 {
1028   for (std::vector<Armap_entry>::const_iterator p = this->armap_.begin();
1029        p != this->armap_.end();
1030        ++p)
1031     {
1032       if (this->seen_offsets_.find(p->file_offset)
1033           == this->seen_offsets_.end())
1034         v->visit(this->armap_names_.data() + p->name_offset);
1035     }
1036 }
1037
1038 // Print statistical information to stderr.  This is used for --stats.
1039
1040 void
1041 Archive::print_stats()
1042 {
1043   fprintf(stderr, _("%s: archive libraries: %u\n"),
1044           program_name, Archive::total_archives);
1045   fprintf(stderr, _("%s: total archive members: %u\n"),
1046           program_name, Archive::total_members);
1047   fprintf(stderr, _("%s: loaded archive members: %u\n"),
1048           program_name, Archive::total_members_loaded);
1049 }
1050
1051 // Add_archive_symbols methods.
1052
1053 Add_archive_symbols::~Add_archive_symbols()
1054 {
1055   if (this->this_blocker_ != NULL)
1056     delete this->this_blocker_;
1057   // next_blocker_ is deleted by the task associated with the next
1058   // input file.
1059 }
1060
1061 // Return whether we can add the archive symbols.  We are blocked by
1062 // this_blocker_.  We block next_blocker_.  We also lock the file.
1063
1064 Task_token*
1065 Add_archive_symbols::is_runnable()
1066 {
1067   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
1068     return this->this_blocker_;
1069   return NULL;
1070 }
1071
1072 void
1073 Add_archive_symbols::locks(Task_locker* tl)
1074 {
1075   tl->add(this, this->next_blocker_);
1076   tl->add(this, this->archive_->token());
1077 }
1078
1079 void
1080 Add_archive_symbols::run(Workqueue* workqueue)
1081 {
1082   // For an incremental link, begin recording layout information.
1083   Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
1084   if (incremental_inputs != NULL)
1085     {
1086       unsigned int arg_serial = this->input_argument_->file().arg_serial();
1087       Script_info* script_info = this->input_argument_->script_info();
1088       incremental_inputs->report_archive_begin(this->archive_, arg_serial,
1089                                                script_info);
1090     }
1091
1092   bool added = this->archive_->add_symbols(this->symtab_, this->layout_,
1093                                            this->input_objects_,
1094                                            this->mapfile_);
1095   this->archive_->unlock_nested_archives();
1096
1097   this->archive_->release();
1098   this->archive_->clear_uncached_views();
1099
1100   if (!added)
1101     {
1102       // This archive holds object files which are incompatible with
1103       // our output file.
1104       Read_symbols::incompatible_warning(this->input_argument_,
1105                                          this->archive_->input_file());
1106       Read_symbols::requeue(workqueue, this->input_objects_, this->symtab_,
1107                             this->layout_, this->dirpath_, this->dirindex_,
1108                             this->mapfile_, this->input_argument_,
1109                             this->input_group_, this->next_blocker_);
1110       delete this->archive_;
1111       return;
1112     }
1113
1114   if (this->input_group_ != NULL)
1115     this->input_group_->add_archive(this->archive_);
1116   else
1117     {
1118       // For an incremental link, finish recording the layout information.
1119       if (incremental_inputs != NULL)
1120         incremental_inputs->report_archive_end(this->archive_);
1121
1122       if (!parameters->options().has_plugins()
1123           || this->archive_->input_file()->options().whole_archive())
1124         {
1125           // We no longer need to know about this archive.
1126           delete this->archive_;
1127         }
1128       else
1129         {
1130           // The plugin interface may want to rescan this archive.
1131           parameters->options().plugins()->save_archive(this->archive_);
1132         }
1133
1134       this->archive_ = NULL;
1135     }
1136 }
1137
1138 // Class Lib_group static variables.
1139 unsigned int Lib_group::total_lib_groups;
1140 unsigned int Lib_group::total_members;
1141 unsigned int Lib_group::total_members_loaded;
1142
1143 Lib_group::Lib_group(const Input_file_lib* lib, Task* task)
1144   : Library_base(task), members_()
1145 {
1146   this->members_.resize(lib->size());
1147 }
1148
1149 const std::string&
1150 Lib_group::do_filename() const
1151 {
1152   std::string *filename = new std::string("/group/");
1153   return *filename;
1154 }
1155
1156 // Select members from the lib group and add them to the link.  We walk
1157 // through the members, and check if each one up should be included.
1158 // If the object says it should be included, we do so.  We have to do
1159 // this in a loop, since including one member may create new undefined
1160 // symbols which may be satisfied by other members.
1161
1162 void
1163 Lib_group::add_symbols(Symbol_table* symtab, Layout* layout,
1164                        Input_objects* input_objects)
1165 {
1166   ++Lib_group::total_lib_groups;
1167
1168   Lib_group::total_members += this->members_.size();
1169
1170   bool added_new_object;
1171   do
1172     {
1173       added_new_object = false;
1174       unsigned int i = 0;
1175       while (i < this->members_.size())
1176         {
1177           const Archive_member& member = this->members_[i];
1178           Object* obj = member.obj_;
1179           std::string why;
1180
1181           // Skip files with no symbols. Plugin objects have
1182           // member.sd_ == NULL.
1183           if (obj != NULL
1184               && (member.sd_ == NULL || member.sd_->symbol_names != NULL))
1185             {
1186               Archive::Should_include t = obj->should_include_member(symtab,
1187                                                                      layout,
1188                                                                      member.sd_,
1189                                                                      &why);
1190
1191               if (t != Archive::SHOULD_INCLUDE_YES)
1192                 {
1193                   ++i;
1194                   continue;
1195                 }
1196
1197               this->include_member(symtab, layout, input_objects, member);
1198
1199               added_new_object = true;
1200             }
1201           else
1202             {
1203               if (member.sd_ != NULL)
1204                 {
1205                   // The file must be locked in order to destroy the views
1206                   // associated with it.
1207                   gold_assert(obj != NULL);
1208                   obj->lock(this->task_);
1209                   delete member.sd_;
1210                   obj->unlock(this->task_);
1211                 }
1212             }
1213
1214           this->members_[i] = this->members_.back();
1215           this->members_.pop_back();
1216         }
1217     }
1218   while (added_new_object);
1219 }
1220
1221 // Include a lib group member in the link.
1222
1223 void
1224 Lib_group::include_member(Symbol_table* symtab, Layout* layout,
1225                           Input_objects* input_objects,
1226                           const Archive_member& member)
1227 {
1228   ++Lib_group::total_members_loaded;
1229
1230   Object* obj = member.obj_;
1231   gold_assert(obj != NULL);
1232
1233   Pluginobj* pluginobj = obj->pluginobj();
1234   if (pluginobj != NULL)
1235     {
1236       pluginobj->add_symbols(symtab, NULL, layout);
1237       return;
1238     }
1239
1240   Read_symbols_data* sd = member.sd_;
1241   gold_assert(sd != NULL);
1242   obj->lock(this->task_);
1243   if (input_objects->add_object(obj))
1244     {
1245       if (layout->incremental_inputs() != NULL)
1246         layout->incremental_inputs()->report_object(obj, member.arg_serial_,
1247                                                     this, NULL);
1248       obj->layout(symtab, layout, sd);
1249       obj->add_symbols(symtab, sd, layout);
1250     }
1251   delete sd;
1252   // Unlock the file for the next task.
1253   obj->unlock(this->task_);
1254 }
1255
1256 // Iterate over all unused symbols, and call the visitor class V for each.
1257
1258 void
1259 Lib_group::do_for_all_unused_symbols(Symbol_visitor_base* v) const
1260 {
1261   // Files are removed from the members list when used, so all the
1262   // files remaining on the list are unused.
1263   for (std::vector<Archive_member>::const_iterator p = this->members_.begin();
1264        p != this->members_.end();
1265        ++p)
1266     {
1267       Object* obj = p->obj_;
1268       obj->for_all_global_symbols(p->sd_, v);
1269     }
1270 }
1271
1272 // Print statistical information to stderr.  This is used for --stats.
1273
1274 void
1275 Lib_group::print_stats()
1276 {
1277   fprintf(stderr, _("%s: lib groups: %u\n"),
1278           program_name, Lib_group::total_lib_groups);
1279   fprintf(stderr, _("%s: total lib groups members: %u\n"),
1280           program_name, Lib_group::total_members);
1281   fprintf(stderr, _("%s: loaded lib groups members: %u\n"),
1282           program_name, Lib_group::total_members_loaded);
1283 }
1284
1285 Task_token*
1286 Add_lib_group_symbols::is_runnable()
1287 {
1288   if (this->readsyms_blocker_ != NULL && this->readsyms_blocker_->is_blocked())
1289     return this->readsyms_blocker_;
1290   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
1291     return this->this_blocker_;
1292   return NULL;
1293 }
1294
1295 void
1296 Add_lib_group_symbols::locks(Task_locker* tl)
1297 {
1298   tl->add(this, this->next_blocker_);
1299 }
1300
1301 void
1302 Add_lib_group_symbols::run(Workqueue*)
1303 {
1304   // For an incremental link, begin recording layout information.
1305   Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
1306   if (incremental_inputs != NULL)
1307     incremental_inputs->report_archive_begin(this->lib_, 0, NULL);
1308
1309   this->lib_->add_symbols(this->symtab_, this->layout_, this->input_objects_);
1310
1311   if (incremental_inputs != NULL)
1312     incremental_inputs->report_archive_end(this->lib_);
1313 }
1314
1315 Add_lib_group_symbols::~Add_lib_group_symbols()
1316 {
1317   if (this->this_blocker_ != NULL)
1318     delete this->this_blocker_;
1319   // next_blocker_ is deleted by the task associated with the next
1320   // input file.
1321 }
1322
1323 } // End namespace gold.