gold/fileread.cc

   1 // fileread.cc -- read files for gold
   2
   3 // Copyright 2006, 2007, 2008 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 <cstring>
  26 #include <cerrno>
  27 #include <fcntl.h>
  28 #include <unistd.h>
  29 #include <sys/mman.h>
  30 #include <sys/uio.h>
  31 #include "filenames.h"
  32
  33 #include "debug.h"
  34 #include "parameters.h"
  35 #include "options.h"
  36 #include "dirsearch.h"
  37 #include "target.h"
  38 #include "binary.h"
  39 #include "descriptors.h"
  40 #include "fileread.h"
  41
  42 namespace gold
  43 {
  44
  45 // Class File_read::View.
  46
  47 File_read::View::~View()
  48 {
  49   gold_assert(!this->is_locked());
  50   if (!this->mapped_)
  51     delete[] this->data_;
  52   else
  53     {
  54       if (::munmap(const_cast<unsigned char*>(this->data_), this->size_) != 0)
  55         gold_warning(_("munmap failed: %s"), strerror(errno));
  56
  57       File_read::current_mapped_bytes -= this->size_;
  58     }
  59 }
  60
  61 void
  62 File_read::View::lock()
  63 {
  64   ++this->lock_count_;
  65 }
  66
  67 void
  68 File_read::View::unlock()
  69 {
  70   gold_assert(this->lock_count_ > 0);
  71   --this->lock_count_;
  72 }
  73
  74 bool
  75 File_read::View::is_locked()
  76 {
  77   return this->lock_count_ > 0;
  78 }
  79
  80 // Class File_read.
  81
  82 // The File_read static variables.
  83 unsigned long long File_read::total_mapped_bytes;
  84 unsigned long long File_read::current_mapped_bytes;
  85 unsigned long long File_read::maximum_mapped_bytes;
  86
  87 File_read::~File_read()
  88 {
  89   gold_assert(this->token_.is_writable());
  90   if (this->is_descriptor_opened_)
  91     {
  92       release_descriptor(this->descriptor_, true);
  93       this->descriptor_ = -1;
  94       this->is_descriptor_opened_ = false;
  95     }
  96   this->name_.clear();
  97   this->clear_views(true);
  98 }
  99
 100 // Open the file.
 101
 102 bool
 103 File_read::open(const Task* task, const std::string& name)
 104 {
 105   gold_assert(this->token_.is_writable()
 106               && this->descriptor_ < 0
 107               && !this->is_descriptor_opened_
 108               && this->name_.empty());
 109   this->name_ = name;
 110
 111   this->descriptor_ = open_descriptor(-1, this->name_.c_str(),
 112                                       O_RDONLY);
 113
 114   if (this->descriptor_ >= 0)
 115     {
 116       this->is_descriptor_opened_ = true;
 117       struct stat s;
 118       if (::fstat(this->descriptor_, &s) < 0)
 119         gold_error(_("%s: fstat failed: %s"),
 120                    this->name_.c_str(), strerror(errno));
 121       this->size_ = s.st_size;
 122       gold_debug(DEBUG_FILES, "Attempt to open %s succeeded",
 123                  this->name_.c_str());
 124     }
 125
 126   this->token_.add_writer(task);
 127
 128   return this->descriptor_ >= 0;
 129 }
 130
 131 // Open the file with the contents in memory.
 132
 133 bool
 134 File_read::open(const Task* task, const std::string& name,
 135                 const unsigned char* contents, off_t size)
 136 {
 137   gold_assert(this->token_.is_writable()
 138               && this->descriptor_ < 0
 139               && !this->is_descriptor_opened_
 140               && this->name_.empty());
 141   this->name_ = name;
 142   this->contents_ = contents;
 143   this->size_ = size;
 144   this->token_.add_writer(task);
 145   return true;
 146 }
 147
 148 // Reopen a descriptor if necessary.
 149
 150 void
 151 File_read::reopen_descriptor()
 152 {
 153   if (!this->is_descriptor_opened_)
 154     {
 155       this->descriptor_ = open_descriptor(this->descriptor_,
 156                                           this->name_.c_str(),
 157                                           O_RDONLY);
 158       if (this->descriptor_ < 0)
 159         gold_fatal(_("could not reopen file %s"), this->name_.c_str());
 160       this->is_descriptor_opened_ = true;
 161     }
 162 }
 163
 164 // Release the file.  This is called when we are done with the file in
 165 // a Task.
 166
 167 void
 168 File_read::release()
 169 {
 170   gold_assert(this->is_locked());
 171
 172   File_read::total_mapped_bytes += this->mapped_bytes_;
 173   File_read::current_mapped_bytes += this->mapped_bytes_;
 174   this->mapped_bytes_ = 0;
 175   if (File_read::current_mapped_bytes > File_read::maximum_mapped_bytes)
 176     File_read::maximum_mapped_bytes = File_read::current_mapped_bytes;
 177
 178   // Only clear views if there is only one attached object.  Otherwise
 179   // we waste time trying to clear cached archive views.  Similarly
 180   // for releasing the descriptor.
 181   if (this->object_count_ <= 1)
 182     {
 183       this->clear_views(false);
 184       if (this->is_descriptor_opened_)
 185         {
 186           release_descriptor(this->descriptor_, false);
 187           this->is_descriptor_opened_ = false;
 188         }
 189     }
 190
 191   this->released_ = true;
 192 }
 193
 194 // Lock the file.
 195
 196 void
 197 File_read::lock(const Task* task)
 198 {
 199   gold_assert(this->released_);
 200   this->token_.add_writer(task);
 201   this->released_ = false;
 202 }
 203
 204 // Unlock the file.
 205
 206 void
 207 File_read::unlock(const Task* task)
 208 {
 209   this->release();
 210   this->token_.remove_writer(task);
 211 }
 212
 213 // Return whether the file is locked.
 214
 215 bool
 216 File_read::is_locked() const
 217 {
 218   if (!this->token_.is_writable())
 219     return true;
 220   // The file is not locked, so it should have been released.
 221   gold_assert(this->released_);
 222   return false;
 223 }
 224
 225 // See if we have a view which covers the file starting at START for
 226 // SIZE bytes.  Return a pointer to the View if found, NULL if not.
 227 // If BYTESHIFT is not -1U, the returned View must have the specified
 228 // byte shift; otherwise, it may have any byte shift.  If VSHIFTED is
 229 // not NULL, this sets *VSHIFTED to a view which would have worked if
 230 // not for the requested BYTESHIFT.
 231
 232 inline File_read::View*
 233 File_read::find_view(off_t start, section_size_type size,
 234                      unsigned int byteshift, File_read::View** vshifted) const
 235 {
 236   if (vshifted != NULL)
 237     *vshifted = NULL;
 238
 239   off_t page = File_read::page_offset(start);
 240
 241   unsigned int bszero = 0;
 242   Views::const_iterator p = this->views_.upper_bound(std::make_pair(page - 1,
 243                                                                     bszero));
 244
 245   while (p != this->views_.end() && p->first.first <= page)
 246     {
 247       if (p->second->start() <= start
 248           && (p->second->start() + static_cast<off_t>(p->second->size())
 249               >= start + static_cast<off_t>(size)))
 250         {
 251           if (byteshift == -1U || byteshift == p->second->byteshift())
 252             {
 253               p->second->set_accessed();
 254               return p->second;
 255             }
 256
 257           if (vshifted != NULL && *vshifted == NULL)
 258             *vshifted = p->second;
 259         }
 260
 261       ++p;
 262     }
 263
 264   return NULL;
 265 }
 266
 267 // Read SIZE bytes from the file starting at offset START.  Read into
 268 // the buffer at P.
 269
 270 void
 271 File_read::do_read(off_t start, section_size_type size, void* p)
 272 {
 273   ssize_t bytes;
 274   if (this->contents_ != NULL)
 275     {
 276       bytes = this->size_ - start;
 277       if (static_cast<section_size_type>(bytes) >= size)
 278         {
 279           memcpy(p, this->contents_ + start, size);
 280           return;
 281         }
 282     }
 283   else
 284     {
 285       this->reopen_descriptor();
 286       bytes = ::pread(this->descriptor_, p, size, start);
 287       if (static_cast<section_size_type>(bytes) == size)
 288         return;
 289
 290       if (bytes < 0)
 291         {
 292           gold_fatal(_("%s: pread failed: %s"),
 293                      this->filename().c_str(), strerror(errno));
 294           return;
 295         }
 296     }
 297
 298   gold_fatal(_("%s: file too short: read only %lld of %lld bytes at %lld"),
 299              this->filename().c_str(),
 300              static_cast<long long>(bytes),
 301              static_cast<long long>(size),
 302              static_cast<long long>(start));
 303 }
 304
 305 // Read data from the file.
 306
 307 void
 308 File_read::read(off_t start, section_size_type size, void* p)
 309 {
 310   const File_read::View* pv = this->find_view(start, size, -1U, NULL);
 311   if (pv != NULL)
 312     {
 313       memcpy(p, pv->data() + (start - pv->start() + pv->byteshift()), size);
 314       return;
 315     }
 316
 317   this->do_read(start, size, p);
 318 }
 319
 320 // Add a new view.  There may already be an existing view at this
 321 // offset.  If there is, the new view will be larger, and should
 322 // replace the old view.
 323
 324 void
 325 File_read::add_view(File_read::View* v)
 326 {
 327   std::pair<Views::iterator, bool> ins =
 328     this->views_.insert(std::make_pair(std::make_pair(v->start(),
 329                                                       v->byteshift()),
 330                                        v));
 331   if (ins.second)
 332     return;
 333
 334   // There was an existing view at this offset.  It must not be large
 335   // enough.  We can't delete it here, since something might be using
 336   // it; we put it on a list to be deleted when the file is unlocked.
 337   File_read::View* vold = ins.first->second;
 338   gold_assert(vold->size() < v->size());
 339   if (vold->should_cache())
 340     {
 341       v->set_cache();
 342       vold->clear_cache();
 343     }
 344   this->saved_views_.push_back(vold);
 345
 346   ins.first->second = v;
 347 }
 348
 349 // Make a new view with a specified byteshift, reading the data from
 350 // the file.
 351
 352 File_read::View*
 353 File_read::make_view(off_t start, section_size_type size,
 354                      unsigned int byteshift, bool cache)
 355 {
 356   gold_assert(size > 0);
 357
 358   off_t poff = File_read::page_offset(start);
 359
 360   section_size_type psize = File_read::pages(size + (start - poff));
 361
 362   if (poff + static_cast<off_t>(psize) >= this->size_)
 363     {
 364       psize = this->size_ - poff;
 365       gold_assert(psize >= size);
 366     }
 367
 368   File_read::View* v;
 369   if (this->contents_ != NULL || byteshift != 0)
 370     {
 371       unsigned char* p = new unsigned char[psize + byteshift];
 372       memset(p, 0, byteshift);
 373       this->do_read(poff, psize, p + byteshift);
 374       v = new File_read::View(poff, psize, p, byteshift, cache, false);
 375     }
 376   else
 377     {
 378       this->reopen_descriptor();
 379       void* p = ::mmap(NULL, psize, PROT_READ, MAP_PRIVATE,
 380                        this->descriptor_, poff);
 381       if (p == MAP_FAILED)
 382         gold_fatal(_("%s: mmap offset %lld size %lld failed: %s"),
 383                    this->filename().c_str(),
 384                    static_cast<long long>(poff),
 385                    static_cast<long long>(psize),
 386                    strerror(errno));
 387
 388       this->mapped_bytes_ += psize;
 389
 390       const unsigned char* pbytes = static_cast<const unsigned char*>(p);
 391       v = new File_read::View(poff, psize, pbytes, 0, cache, true);
 392     }
 393
 394   this->add_view(v);
 395
 396   return v;
 397 }
 398
 399 // Find a View or make a new one, shifted as required by the file
 400 // offset OFFSET and ALIGNED.
 401
 402 File_read::View*
 403 File_read::find_or_make_view(off_t offset, off_t start,
 404                              section_size_type size, bool aligned, bool cache)
 405 {
 406   unsigned int byteshift;
 407   if (offset == 0)
 408     byteshift = 0;
 409   else
 410     {
 411       unsigned int target_size = (!parameters->target_valid()
 412                                   ? 64
 413                                   : parameters->target().get_size());
 414       byteshift = offset & ((target_size / 8) - 1);
 415
 416       // Set BYTESHIFT to the number of dummy bytes which must be
 417       // inserted before the data in order for this data to be
 418       // aligned.
 419       if (byteshift != 0)
 420         byteshift = (target_size / 8) - byteshift;
 421     }
 422
 423   // Try to find a View with the required BYTESHIFT.
 424   File_read::View* vshifted;
 425   File_read::View* v = this->find_view(offset + start, size,
 426                                        aligned ? byteshift : -1U,
 427                                        &vshifted);
 428   if (v != NULL)
 429     {
 430       if (cache)
 431         v->set_cache();
 432       return v;
 433     }
 434
 435   // If VSHIFTED is not NULL, then it has the data we need, but with
 436   // the wrong byteshift.
 437   v = vshifted;
 438   if (v != NULL)
 439     {
 440       gold_assert(aligned);
 441
 442       unsigned char* pbytes = new unsigned char[v->size() + byteshift];
 443       memset(pbytes, 0, byteshift);
 444       memcpy(pbytes + byteshift, v->data() + v->byteshift(), v->size());
 445
 446       File_read::View* shifted_view = new File_read::View(v->start(), v->size(),
 447                                                           pbytes, byteshift,
 448                                                           cache, false);
 449
 450       this->add_view(shifted_view);
 451       return shifted_view;
 452     }
 453
 454   // Make a new view.  If we don't need an aligned view, use a
 455   // byteshift of 0, so that we can use mmap.
 456   return this->make_view(offset + start, size,
 457                          aligned ? byteshift : 0,
 458                          cache);
 459 }
 460
 461 // Get a view into the file.
 462
 463 const unsigned char*
 464 File_read::get_view(off_t offset, off_t start, section_size_type size,
 465                     bool aligned, bool cache)
 466 {
 467   File_read::View* pv = this->find_or_make_view(offset, start, size,
 468                                                 aligned, cache);
 469   return pv->data() + (offset + start - pv->start() + pv->byteshift());
 470 }
 471
 472 File_view*
 473 File_read::get_lasting_view(off_t offset, off_t start, section_size_type size,
 474                             bool aligned, bool cache)
 475 {
 476   File_read::View* pv = this->find_or_make_view(offset, start, size,
 477                                                 aligned, cache);
 478   pv->lock();
 479   return new File_view(*this, pv,
 480                        (pv->data()
 481                         + (offset + start - pv->start() + pv->byteshift())));
 482 }
 483
 484 // Use readv to read COUNT entries from RM starting at START.  BASE
 485 // must be added to all file offsets in RM.
 486
 487 void
 488 File_read::do_readv(off_t base, const Read_multiple& rm, size_t start,
 489                     size_t count)
 490 {
 491   unsigned char discard[File_read::page_size];
 492   iovec iov[File_read::max_readv_entries * 2];
 493   size_t iov_index = 0;
 494
 495   off_t first_offset = rm[start].file_offset;
 496   off_t last_offset = first_offset;
 497   ssize_t want = 0;
 498   for (size_t i = 0; i < count; ++i)
 499     {
 500       const Read_multiple_entry& i_entry(rm[start + i]);
 501
 502       if (i_entry.file_offset > last_offset)
 503         {
 504           size_t skip = i_entry.file_offset - last_offset;
 505           gold_assert(skip <= sizeof discard);
 506
 507           iov[iov_index].iov_base = discard;
 508           iov[iov_index].iov_len = skip;
 509           ++iov_index;
 510
 511           want += skip;
 512         }
 513
 514       iov[iov_index].iov_base = i_entry.buffer;
 515       iov[iov_index].iov_len = i_entry.size;
 516       ++iov_index;
 517
 518       want += i_entry.size;
 519
 520       last_offset = i_entry.file_offset + i_entry.size;
 521     }
 522
 523   this->reopen_descriptor();
 524
 525   gold_assert(iov_index < sizeof iov / sizeof iov[0]);
 526
 527   if (::lseek(this->descriptor_, base + first_offset, SEEK_SET) < 0)
 528     gold_fatal(_("%s: lseek failed: %s"),
 529                this->filename().c_str(), strerror(errno));
 530
 531   ssize_t got = ::readv(this->descriptor_, iov, iov_index);
 532
 533   if (got < 0)
 534     gold_fatal(_("%s: readv failed: %s"),
 535                this->filename().c_str(), strerror(errno));
 536   if (got != want)
 537     gold_fatal(_("%s: file too short: read only %zd of %zd bytes at %lld"),
 538                this->filename().c_str(),
 539                got, want, static_cast<long long>(base + first_offset));
 540 }
 541
 542 // Read several pieces of data from the file.
 543
 544 void
 545 File_read::read_multiple(off_t base, const Read_multiple& rm)
 546 {
 547   size_t count = rm.size();
 548   size_t i = 0;
 549   while (i < count)
 550     {
 551       // Find up to MAX_READV_ENTRIES consecutive entries which are
 552       // less than one page apart.
 553       const Read_multiple_entry& i_entry(rm[i]);
 554       off_t i_off = i_entry.file_offset;
 555       off_t end_off = i_off + i_entry.size;
 556       size_t j;
 557       for (j = i + 1; j < count; ++j)
 558         {
 559           if (j - i >= File_read::max_readv_entries)
 560             break;
 561           const Read_multiple_entry& j_entry(rm[j]);
 562           off_t j_off = j_entry.file_offset;
 563           gold_assert(j_off >= end_off);
 564           off_t j_end_off = j_off + j_entry.size;
 565           if (j_end_off - end_off >= File_read::page_size)
 566             break;
 567           end_off = j_end_off;
 568         }
 569
 570       if (j == i + 1)
 571         this->read(base + i_off, i_entry.size, i_entry.buffer);
 572       else
 573         {
 574           File_read::View* view = this->find_view(base + i_off,
 575                                                   end_off - i_off,
 576                                                   -1U, NULL);
 577           if (view == NULL)
 578             this->do_readv(base, rm, i, j - i);
 579           else
 580             {
 581               const unsigned char* v = (view->data()
 582                                         + (base + i_off - view->start()
 583                                            + view->byteshift()));
 584               for (size_t k = i; k < j; ++k)
 585                 {
 586                   const Read_multiple_entry& k_entry(rm[k]);
 587                   gold_assert((convert_to_section_size_type(k_entry.file_offset
 588                                                            - i_off)
 589                                + k_entry.size)
 590                               <= convert_to_section_size_type(end_off
 591                                                               - i_off));
 592                   memcpy(k_entry.buffer,
 593                          v + (k_entry.file_offset - i_off),
 594                          k_entry.size);
 595                 }
 596             }
 597         }
 598
 599       i = j;
 600     }
 601 }
 602
 603 // Mark all views as no longer cached.
 604
 605 void
 606 File_read::clear_view_cache_marks()
 607 {
 608   // Just ignore this if there are multiple objects associated with
 609   // the file.  Otherwise we will wind up uncaching and freeing some
 610   // views for other objects.
 611   if (this->object_count_ > 1)
 612     return;
 613
 614   for (Views::iterator p = this->views_.begin();
 615        p != this->views_.end();
 616        ++p)
 617     p->second->clear_cache();
 618   for (Saved_views::iterator p = this->saved_views_.begin();
 619        p != this->saved_views_.end();
 620        ++p)
 621     (*p)->clear_cache();
 622 }
 623
 624 // Remove all the file views.  For a file which has multiple
 625 // associated objects (i.e., an archive), we keep accessed views
 626 // around until next time, in the hopes that they will be useful for
 627 // the next object.
 628
 629 void
 630 File_read::clear_views(bool destroying)
 631 {
 632   Views::iterator p = this->views_.begin();
 633   while (p != this->views_.end())
 634     {
 635       bool should_delete;
 636       if (p->second->is_locked())
 637         should_delete = false;
 638       else if (destroying)
 639         should_delete = true;
 640       else if (p->second->should_cache())
 641         should_delete = false;
 642       else if (this->object_count_ > 1 && p->second->accessed())
 643         should_delete = false;
 644       else
 645         should_delete = true;
 646
 647       if (should_delete)
 648         {
 649           delete p->second;
 650
 651           // map::erase invalidates only the iterator to the deleted
 652           // element.
 653           Views::iterator pe = p;
 654           ++p;
 655           this->views_.erase(pe);
 656         }
 657       else
 658         {
 659           gold_assert(!destroying);
 660           p->second->clear_accessed();
 661           ++p;
 662         }
 663     }
 664
 665   Saved_views::iterator q = this->saved_views_.begin();
 666   while (q != this->saved_views_.end())
 667     {
 668       if (!(*q)->is_locked())
 669         {
 670           delete *q;
 671           q = this->saved_views_.erase(q);
 672         }
 673       else
 674         {
 675           gold_assert(!destroying);
 676           ++q;
 677         }
 678     }
 679 }
 680
 681 // Print statistical information to stderr.  This is used for --stats.
 682
 683 void
 684 File_read::print_stats()
 685 {
 686   fprintf(stderr, _("%s: total bytes mapped for read: %llu\n"),
 687           program_name, File_read::total_mapped_bytes);
 688   fprintf(stderr, _("%s: maximum bytes mapped for read at one time: %llu\n"),
 689           program_name, File_read::maximum_mapped_bytes);
 690 }
 691
 692 // Class File_view.
 693
 694 File_view::~File_view()
 695 {
 696   gold_assert(this->file_.is_locked());
 697   this->view_->unlock();
 698 }
 699
 700 // Class Input_file.
 701
 702 // Create a file for testing.
 703
 704 Input_file::Input_file(const Task* task, const char* name,
 705                        const unsigned char* contents, off_t size)
 706   : file_()
 707 {
 708   this->input_argument_ =
 709     new Input_file_argument(name, false, "", false,
 710                             Position_dependent_options());
 711   bool ok = file_.open(task, name, contents, size);
 712   gold_assert(ok);
 713 }
 714
 715 // Return the position dependent options in force for this file.
 716
 717 const Position_dependent_options&
 718 Input_file::options() const
 719 {
 720   return this->input_argument_->options();
 721 }
 722
 723 // Return the name given by the user.  For -lc this will return "c".
 724
 725 const char*
 726 Input_file::name() const
 727 {
 728   return this->input_argument_->name();
 729 }
 730
 731 // Return whether we are only reading symbols.
 732
 733 bool
 734 Input_file::just_symbols() const
 735 {
 736   return this->input_argument_->just_symbols();
 737 }
 738
 739 // Open the file.
 740
 741 // If the filename is not absolute, we assume it is in the current
 742 // directory *except* when:
 743 //    A) input_argument_->is_lib() is true; or
 744 //    B) input_argument_->extra_search_path() is not empty.
 745 // In both cases, we look in extra_search_path + library_path to find
 746 // the file location, rather than the current directory.
 747
 748 bool
 749 Input_file::open(const General_options& options, const Dirsearch& dirpath,
 750                  const Task* task)
 751 {
 752   std::string name;
 753
 754   // Case 1: name is an absolute file, just try to open it
 755   // Case 2: name is relative but is_lib is false and extra_search_path
 756   //         is empty
 757   if (IS_ABSOLUTE_PATH (this->input_argument_->name())
 758       || (!this->input_argument_->is_lib()
 759           && this->input_argument_->extra_search_path() == NULL))
 760     {
 761       name = this->input_argument_->name();
 762       this->found_name_ = name;
 763     }
 764   // Case 3: is_lib is true
 765   else if (this->input_argument_->is_lib())
 766     {
 767       // We don't yet support extra_search_path with -l.
 768       gold_assert(this->input_argument_->extra_search_path() == NULL);
 769       std::string n1("lib");
 770       n1 += this->input_argument_->name();
 771       std::string n2;
 772       if (options.is_static()
 773           || !this->input_argument_->options().Bdynamic())
 774         n1 += ".a";
 775       else
 776         {
 777           n2 = n1 + ".a";
 778           n1 += ".so";
 779         }
 780       name = dirpath.find(n1, n2, &this->is_in_sysroot_);
 781       if (name.empty())
 782         {
 783           gold_error(_("cannot find -l%s"),
 784                      this->input_argument_->name());
 785           return false;
 786         }
 787       if (n2.empty() || name[name.length() - 1] == 'o')
 788         this->found_name_ = n1;
 789       else
 790         this->found_name_ = n2;
 791     }
 792   // Case 4: extra_search_path is not empty
 793   else
 794     {
 795       gold_assert(this->input_argument_->extra_search_path() != NULL);
 796
 797       // First, check extra_search_path.
 798       name = this->input_argument_->extra_search_path();
 799       if (!IS_DIR_SEPARATOR (name[name.length() - 1]))
 800         name += '/';
 801       name += this->input_argument_->name();
 802       struct stat dummy_stat;
 803       if (::stat(name.c_str(), &dummy_stat) < 0)
 804         {
 805           // extra_search_path failed, so check the normal search-path.
 806           name = dirpath.find(this->input_argument_->name(), "",
 807                               &this->is_in_sysroot_);
 808           if (name.empty())
 809             {
 810               gold_error(_("cannot find %s"),
 811                          this->input_argument_->name());
 812               return false;
 813             }
 814         }
 815       this->found_name_ = this->input_argument_->name();
 816     }
 817
 818   // Now that we've figured out where the file lives, try to open it.
 819
 820   General_options::Object_format format =
 821     this->input_argument_->options().format_enum();
 822   bool ok;
 823   if (format == General_options::OBJECT_FORMAT_ELF)
 824     ok = this->file_.open(task, name);
 825   else
 826     {
 827       gold_assert(format == General_options::OBJECT_FORMAT_BINARY);
 828       ok = this->open_binary(options, task, name);
 829     }
 830
 831   if (!ok)
 832     {
 833       gold_error(_("cannot open %s: %s"),
 834                  name.c_str(), strerror(errno));
 835       return false;
 836     }
 837
 838   return true;
 839 }
 840
 841 // Open a file for --format binary.
 842
 843 bool
 844 Input_file::open_binary(const General_options&,
 845                         const Task* task, const std::string& name)
 846 {
 847   // In order to open a binary file, we need machine code, size, and
 848   // endianness.  We may not have a valid target at this point, in
 849   // which case we use the default target.
 850   const Target* target;
 851   if (parameters->target_valid())
 852     target = &parameters->target();
 853   else
 854     target = &parameters->default_target();
 855
 856   Binary_to_elf binary_to_elf(target->machine_code(),
 857                               target->get_size(),
 858                               target->is_big_endian(),
 859                               name);
 860   if (!binary_to_elf.convert(task))
 861     return false;
 862   return this->file_.open(task, name, binary_to_elf.converted_data_leak(),
 863                           binary_to_elf.converted_size());
 864 }
 865
 866 } // End namespace gold.