gold/fileread.cc

   1 // fileread.cc -- read files for gold
   2
   3 // Copyright 2006, 2007, 2008, 2009 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 <sys/stat.h>
  32 #include "filenames.h"
  33
  34 #include "debug.h"
  35 #include "parameters.h"
  36 #include "options.h"
  37 #include "dirsearch.h"
  38 #include "target.h"
  39 #include "binary.h"
  40 #include "descriptors.h"
  41 #include "fileread.h"
  42
  43 #ifndef HAVE_READV
  44 struct iovec { void* iov_base; size_t iov_len };
  45 ssize_t
  46 readv(int, const iovec*, int)
  47 {
  48   gold_unreachable();
  49 }
  50 #endif
  51
  52 namespace gold
  53 {
  54
  55 // Class File_read::View.
  56
  57 File_read::View::~View()
  58 {
  59   gold_assert(!this->is_locked());
  60   switch (this->data_ownership_)
  61     {
  62     case DATA_ALLOCATED_ARRAY:
  63       delete[] this->data_;
  64       break;
  65     case DATA_MMAPPED:
  66       if (::munmap(const_cast<unsigned char*>(this->data_), this->size_) != 0)
  67         gold_warning(_("munmap failed: %s"), strerror(errno));
  68       File_read::current_mapped_bytes -= this->size_;
  69       break;
  70     case DATA_NOT_OWNED:
  71       break;
  72     default:
  73       gold_unreachable();
  74     }
  75 }
  76
  77 void
  78 File_read::View::lock()
  79 {
  80   ++this->lock_count_;
  81 }
  82
  83 void
  84 File_read::View::unlock()
  85 {
  86   gold_assert(this->lock_count_ > 0);
  87   --this->lock_count_;
  88 }
  89
  90 bool
  91 File_read::View::is_locked()
  92 {
  93   return this->lock_count_ > 0;
  94 }
  95
  96 // Class File_read.
  97
  98 // The File_read static variables.
  99 unsigned long long File_read::total_mapped_bytes;
 100 unsigned long long File_read::current_mapped_bytes;
 101 unsigned long long File_read::maximum_mapped_bytes;
 102
 103 File_read::~File_read()
 104 {
 105   gold_assert(this->token_.is_writable());
 106   if (this->is_descriptor_opened_)
 107     {
 108       release_descriptor(this->descriptor_, true);
 109       this->descriptor_ = -1;
 110       this->is_descriptor_opened_ = false;
 111     }
 112   this->name_.clear();
 113   this->clear_views(true);
 114   if (this->whole_file_view_)
 115     delete this->whole_file_view_;
 116 }
 117
 118 // Open the file.
 119
 120 bool
 121 File_read::open(const Task* task, const std::string& name)
 122 {
 123   gold_assert(this->token_.is_writable()
 124               && this->descriptor_ < 0
 125               && !this->is_descriptor_opened_
 126               && this->name_.empty());
 127   this->name_ = name;
 128
 129   this->descriptor_ = open_descriptor(-1, this->name_.c_str(),
 130                                       O_RDONLY);
 131
 132   if (this->descriptor_ >= 0)
 133     {
 134       this->is_descriptor_opened_ = true;
 135       struct stat s;
 136       if (::fstat(this->descriptor_, &s) < 0)
 137         gold_error(_("%s: fstat failed: %s"),
 138                    this->name_.c_str(), strerror(errno));
 139       this->size_ = s.st_size;
 140       gold_debug(DEBUG_FILES, "Attempt to open %s succeeded",
 141                  this->name_.c_str());
 142
 143       // Options may not yet be ready e.g. when reading a version
 144       // script.  We then default to --no-keep-files-mapped.
 145       if (parameters->options_valid()
 146           && parameters->options().keep_files_mapped())
 147         {
 148           const unsigned char* contents = static_cast<const unsigned char*>(
 149               ::mmap(NULL, this->size_, PROT_READ, MAP_PRIVATE,
 150                      this->descriptor_, 0));
 151           if (contents == MAP_FAILED)
 152             gold_fatal(_("%s: mmap failed: %s"), this->filename().c_str(),
 153                        strerror(errno));
 154           this->whole_file_view_ = new View(0, this->size_, contents, 0, false,
 155                                             View::DATA_MMAPPED);
 156           this->mapped_bytes_ += this->size_;
 157         }
 158
 159       this->token_.add_writer(task);
 160     }
 161
 162   return this->descriptor_ >= 0;
 163 }
 164
 165 // Open the file with the contents in memory.
 166
 167 bool
 168 File_read::open(const Task* task, const std::string& name,
 169                 const unsigned char* contents, off_t size)
 170 {
 171   gold_assert(this->token_.is_writable()
 172               && this->descriptor_ < 0
 173               && !this->is_descriptor_opened_
 174               && this->name_.empty());
 175   this->name_ = name;
 176   this->whole_file_view_ = new View(0, size, contents, 0, false,
 177                                     View::DATA_NOT_OWNED);
 178   this->size_ = size;
 179   this->token_.add_writer(task);
 180   return true;
 181 }
 182
 183 // Reopen a descriptor if necessary.
 184
 185 void
 186 File_read::reopen_descriptor()
 187 {
 188   if (!this->is_descriptor_opened_)
 189     {
 190       this->descriptor_ = open_descriptor(this->descriptor_,
 191                                           this->name_.c_str(),
 192                                           O_RDONLY);
 193       if (this->descriptor_ < 0)
 194         gold_fatal(_("could not reopen file %s"), this->name_.c_str());
 195       this->is_descriptor_opened_ = true;
 196     }
 197 }
 198
 199 // Release the file.  This is called when we are done with the file in
 200 // a Task.
 201
 202 void
 203 File_read::release()
 204 {
 205   gold_assert(this->is_locked());
 206
 207   File_read::total_mapped_bytes += this->mapped_bytes_;
 208   File_read::current_mapped_bytes += this->mapped_bytes_;
 209   this->mapped_bytes_ = 0;
 210   if (File_read::current_mapped_bytes > File_read::maximum_mapped_bytes)
 211     File_read::maximum_mapped_bytes = File_read::current_mapped_bytes;
 212
 213   // Only clear views if there is only one attached object.  Otherwise
 214   // we waste time trying to clear cached archive views.  Similarly
 215   // for releasing the descriptor.
 216   if (this->object_count_ <= 1)
 217     {
 218       this->clear_views(false);
 219       if (this->is_descriptor_opened_)
 220         {
 221           release_descriptor(this->descriptor_, false);
 222           this->is_descriptor_opened_ = false;
 223         }
 224     }
 225
 226   this->released_ = true;
 227 }
 228
 229 // Lock the file.
 230
 231 void
 232 File_read::lock(const Task* task)
 233 {
 234   gold_assert(this->released_);
 235   this->token_.add_writer(task);
 236   this->released_ = false;
 237 }
 238
 239 // Unlock the file.
 240
 241 void
 242 File_read::unlock(const Task* task)
 243 {
 244   this->release();
 245   this->token_.remove_writer(task);
 246 }
 247
 248 // Return whether the file is locked.
 249
 250 bool
 251 File_read::is_locked() const
 252 {
 253   if (!this->token_.is_writable())
 254     return true;
 255   // The file is not locked, so it should have been released.
 256   gold_assert(this->released_);
 257   return false;
 258 }
 259
 260 // See if we have a view which covers the file starting at START for
 261 // SIZE bytes.  Return a pointer to the View if found, NULL if not.
 262 // If BYTESHIFT is not -1U, the returned View must have the specified
 263 // byte shift; otherwise, it may have any byte shift.  If VSHIFTED is
 264 // not NULL, this sets *VSHIFTED to a view which would have worked if
 265 // not for the requested BYTESHIFT.
 266
 267 inline File_read::View*
 268 File_read::find_view(off_t start, section_size_type size,
 269                      unsigned int byteshift, File_read::View** vshifted) const
 270 {
 271   if (vshifted != NULL)
 272     *vshifted = NULL;
 273
 274   // If we have the whole file mmapped, and the alignment is right,
 275   // we can return it.
 276   if (this->whole_file_view_)
 277     if (byteshift == -1U || byteshift == 0)
 278       return this->whole_file_view_;
 279
 280   off_t page = File_read::page_offset(start);
 281
 282   unsigned int bszero = 0;
 283   Views::const_iterator p = this->views_.upper_bound(std::make_pair(page - 1,
 284                                                                     bszero));
 285
 286   while (p != this->views_.end() && p->first.first <= page)
 287     {
 288       if (p->second->start() <= start
 289           && (p->second->start() + static_cast<off_t>(p->second->size())
 290               >= start + static_cast<off_t>(size)))
 291         {
 292           if (byteshift == -1U || byteshift == p->second->byteshift())
 293             {
 294               p->second->set_accessed();
 295               return p->second;
 296             }
 297
 298           if (vshifted != NULL && *vshifted == NULL)
 299             *vshifted = p->second;
 300         }
 301
 302       ++p;
 303     }
 304
 305   return NULL;
 306 }
 307
 308 // Read SIZE bytes from the file starting at offset START.  Read into
 309 // the buffer at P.
 310
 311 void
 312 File_read::do_read(off_t start, section_size_type size, void* p)
 313 {
 314   ssize_t bytes;
 315   if (this->whole_file_view_ != NULL)
 316     {
 317       bytes = this->size_ - start;
 318       if (static_cast<section_size_type>(bytes) >= size)
 319         {
 320           memcpy(p, this->whole_file_view_->data() + start, size);
 321           return;
 322         }
 323     }
 324   else
 325     {
 326       this->reopen_descriptor();
 327       bytes = ::pread(this->descriptor_, p, size, start);
 328       if (static_cast<section_size_type>(bytes) == size)
 329         return;
 330
 331       if (bytes < 0)
 332         {
 333           gold_fatal(_("%s: pread failed: %s"),
 334                      this->filename().c_str(), strerror(errno));
 335           return;
 336         }
 337     }
 338
 339   gold_fatal(_("%s: file too short: read only %lld of %lld bytes at %lld"),
 340              this->filename().c_str(),
 341              static_cast<long long>(bytes),
 342              static_cast<long long>(size),
 343              static_cast<long long>(start));
 344 }
 345
 346 // Read data from the file.
 347
 348 void
 349 File_read::read(off_t start, section_size_type size, void* p)
 350 {
 351   const File_read::View* pv = this->find_view(start, size, -1U, NULL);
 352   if (pv != NULL)
 353     {
 354       memcpy(p, pv->data() + (start - pv->start() + pv->byteshift()), size);
 355       return;
 356     }
 357
 358   this->do_read(start, size, p);
 359 }
 360
 361 // Add a new view.  There may already be an existing view at this
 362 // offset.  If there is, the new view will be larger, and should
 363 // replace the old view.
 364
 365 void
 366 File_read::add_view(File_read::View* v)
 367 {
 368   std::pair<Views::iterator, bool> ins =
 369     this->views_.insert(std::make_pair(std::make_pair(v->start(),
 370                                                       v->byteshift()),
 371                                        v));
 372   if (ins.second)
 373     return;
 374
 375   // There was an existing view at this offset.  It must not be large
 376   // enough.  We can't delete it here, since something might be using
 377   // it; we put it on a list to be deleted when the file is unlocked.
 378   File_read::View* vold = ins.first->second;
 379   gold_assert(vold->size() < v->size());
 380   if (vold->should_cache())
 381     {
 382       v->set_cache();
 383       vold->clear_cache();
 384     }
 385   this->saved_views_.push_back(vold);
 386
 387   ins.first->second = v;
 388 }
 389
 390 // Make a new view with a specified byteshift, reading the data from
 391 // the file.
 392
 393 File_read::View*
 394 File_read::make_view(off_t start, section_size_type size,
 395                      unsigned int byteshift, bool cache)
 396 {
 397   gold_assert(size > 0);
 398
 399   // Check that start and end of the view are within the file.
 400   if (start > this->size_
 401       || (static_cast<unsigned long long>(size)
 402           > static_cast<unsigned long long>(this->size_ - start)))
 403     gold_fatal(_("%s: attempt to map %lld bytes at offset %lld exceeds "
 404                  "size of file; the file may be corrupt"),
 405                    this->filename().c_str(),
 406                    static_cast<long long>(size),
 407                    static_cast<long long>(start));
 408
 409   off_t poff = File_read::page_offset(start);
 410
 411   section_size_type psize = File_read::pages(size + (start - poff));
 412
 413   if (poff + static_cast<off_t>(psize) >= this->size_)
 414     {
 415       psize = this->size_ - poff;
 416       gold_assert(psize >= size);
 417     }
 418
 419   File_read::View* v;
 420   if (this->whole_file_view_ != NULL || byteshift != 0)
 421     {
 422       unsigned char* p = new unsigned char[psize + byteshift];
 423       memset(p, 0, byteshift);
 424       this->do_read(poff, psize, p + byteshift);
 425       v = new File_read::View(poff, psize, p, byteshift, cache,
 426                               View::DATA_ALLOCATED_ARRAY);
 427     }
 428   else
 429     {
 430       this->reopen_descriptor();
 431       void* p = ::mmap(NULL, psize, PROT_READ, MAP_PRIVATE,
 432                        this->descriptor_, poff);
 433       if (p == MAP_FAILED)
 434         gold_fatal(_("%s: mmap offset %lld size %lld failed: %s"),
 435                    this->filename().c_str(),
 436                    static_cast<long long>(poff),
 437                    static_cast<long long>(psize),
 438                    strerror(errno));
 439
 440       this->mapped_bytes_ += psize;
 441
 442       const unsigned char* pbytes = static_cast<const unsigned char*>(p);
 443       v = new File_read::View(poff, psize, pbytes, 0, cache,
 444                               View::DATA_MMAPPED);
 445     }
 446
 447   this->add_view(v);
 448
 449   return v;
 450 }
 451
 452 // Find a View or make a new one, shifted as required by the file
 453 // offset OFFSET and ALIGNED.
 454
 455 File_read::View*
 456 File_read::find_or_make_view(off_t offset, off_t start,
 457                              section_size_type size, bool aligned, bool cache)
 458 {
 459   unsigned int byteshift;
 460   if (offset == 0)
 461     byteshift = 0;
 462   else
 463     {
 464       unsigned int target_size = (!parameters->target_valid()
 465                                   ? 64
 466                                   : parameters->target().get_size());
 467       byteshift = offset & ((target_size / 8) - 1);
 468
 469       // Set BYTESHIFT to the number of dummy bytes which must be
 470       // inserted before the data in order for this data to be
 471       // aligned.
 472       if (byteshift != 0)
 473         byteshift = (target_size / 8) - byteshift;
 474     }
 475
 476   // Try to find a View with the required BYTESHIFT.
 477   File_read::View* vshifted;
 478   File_read::View* v = this->find_view(offset + start, size,
 479                                        aligned ? byteshift : -1U,
 480                                        &vshifted);
 481   if (v != NULL)
 482     {
 483       if (cache)
 484         v->set_cache();
 485       return v;
 486     }
 487
 488   // If VSHIFTED is not NULL, then it has the data we need, but with
 489   // the wrong byteshift.
 490   v = vshifted;
 491   if (v != NULL)
 492     {
 493       gold_assert(aligned);
 494
 495       unsigned char* pbytes = new unsigned char[v->size() + byteshift];
 496       memset(pbytes, 0, byteshift);
 497       memcpy(pbytes + byteshift, v->data() + v->byteshift(), v->size());
 498
 499       File_read::View* shifted_view =
 500           new File_read::View(v->start(), v->size(), pbytes, byteshift,
 501                               cache, View::DATA_ALLOCATED_ARRAY);
 502
 503       this->add_view(shifted_view);
 504       return shifted_view;
 505     }
 506
 507   // Make a new view.  If we don't need an aligned view, use a
 508   // byteshift of 0, so that we can use mmap.
 509   return this->make_view(offset + start, size,
 510                          aligned ? byteshift : 0,
 511                          cache);
 512 }
 513
 514 // Get a view into the file.
 515
 516 const unsigned char*
 517 File_read::get_view(off_t offset, off_t start, section_size_type size,
 518                     bool aligned, bool cache)
 519 {
 520   File_read::View* pv = this->find_or_make_view(offset, start, size,
 521                                                 aligned, cache);
 522   return pv->data() + (offset + start - pv->start() + pv->byteshift());
 523 }
 524
 525 File_view*
 526 File_read::get_lasting_view(off_t offset, off_t start, section_size_type size,
 527                             bool aligned, bool cache)
 528 {
 529   File_read::View* pv = this->find_or_make_view(offset, start, size,
 530                                                 aligned, cache);
 531   pv->lock();
 532   return new File_view(*this, pv,
 533                        (pv->data()
 534                         + (offset + start - pv->start() + pv->byteshift())));
 535 }
 536
 537 // Use readv to read COUNT entries from RM starting at START.  BASE
 538 // must be added to all file offsets in RM.
 539
 540 void
 541 File_read::do_readv(off_t base, const Read_multiple& rm, size_t start,
 542                     size_t count)
 543 {
 544   unsigned char discard[File_read::page_size];
 545   iovec iov[File_read::max_readv_entries * 2];
 546   size_t iov_index = 0;
 547
 548   off_t first_offset = rm[start].file_offset;
 549   off_t last_offset = first_offset;
 550   ssize_t want = 0;
 551   for (size_t i = 0; i < count; ++i)
 552     {
 553       const Read_multiple_entry& i_entry(rm[start + i]);
 554
 555       if (i_entry.file_offset > last_offset)
 556         {
 557           size_t skip = i_entry.file_offset - last_offset;
 558           gold_assert(skip <= sizeof discard);
 559
 560           iov[iov_index].iov_base = discard;
 561           iov[iov_index].iov_len = skip;
 562           ++iov_index;
 563
 564           want += skip;
 565         }
 566
 567       iov[iov_index].iov_base = i_entry.buffer;
 568       iov[iov_index].iov_len = i_entry.size;
 569       ++iov_index;
 570
 571       want += i_entry.size;
 572
 573       last_offset = i_entry.file_offset + i_entry.size;
 574     }
 575
 576   this->reopen_descriptor();
 577
 578   gold_assert(iov_index < sizeof iov / sizeof iov[0]);
 579
 580   if (::lseek(this->descriptor_, base + first_offset, SEEK_SET) < 0)
 581     gold_fatal(_("%s: lseek failed: %s"),
 582                this->filename().c_str(), strerror(errno));
 583
 584   ssize_t got = ::readv(this->descriptor_, iov, iov_index);
 585
 586   if (got < 0)
 587     gold_fatal(_("%s: readv failed: %s"),
 588                this->filename().c_str(), strerror(errno));
 589   if (got != want)
 590     gold_fatal(_("%s: file too short: read only %zd of %zd bytes at %lld"),
 591                this->filename().c_str(),
 592                got, want, static_cast<long long>(base + first_offset));
 593 }
 594
 595 // Read several pieces of data from the file.
 596
 597 void
 598 File_read::read_multiple(off_t base, const Read_multiple& rm)
 599 {
 600   size_t count = rm.size();
 601   size_t i = 0;
 602   while (i < count)
 603     {
 604       // Find up to MAX_READV_ENTRIES consecutive entries which are
 605       // less than one page apart.
 606       const Read_multiple_entry& i_entry(rm[i]);
 607       off_t i_off = i_entry.file_offset;
 608       off_t end_off = i_off + i_entry.size;
 609       size_t j;
 610       for (j = i + 1; j < count; ++j)
 611         {
 612           if (j - i >= File_read::max_readv_entries)
 613             break;
 614           const Read_multiple_entry& j_entry(rm[j]);
 615           off_t j_off = j_entry.file_offset;
 616           gold_assert(j_off >= end_off);
 617           off_t j_end_off = j_off + j_entry.size;
 618           if (j_end_off - end_off >= File_read::page_size)
 619             break;
 620           end_off = j_end_off;
 621         }
 622
 623       if (j == i + 1)
 624         this->read(base + i_off, i_entry.size, i_entry.buffer);
 625       else
 626         {
 627           File_read::View* view = this->find_view(base + i_off,
 628                                                   end_off - i_off,
 629                                                   -1U, NULL);
 630           if (view == NULL)
 631             this->do_readv(base, rm, i, j - i);
 632           else
 633             {
 634               const unsigned char* v = (view->data()
 635                                         + (base + i_off - view->start()
 636                                            + view->byteshift()));
 637               for (size_t k = i; k < j; ++k)
 638                 {
 639                   const Read_multiple_entry& k_entry(rm[k]);
 640                   gold_assert((convert_to_section_size_type(k_entry.file_offset
 641                                                            - i_off)
 642                                + k_entry.size)
 643                               <= convert_to_section_size_type(end_off
 644                                                               - i_off));
 645                   memcpy(k_entry.buffer,
 646                          v + (k_entry.file_offset - i_off),
 647                          k_entry.size);
 648                 }
 649             }
 650         }
 651
 652       i = j;
 653     }
 654 }
 655
 656 // Mark all views as no longer cached.
 657
 658 void
 659 File_read::clear_view_cache_marks()
 660 {
 661   // Just ignore this if there are multiple objects associated with
 662   // the file.  Otherwise we will wind up uncaching and freeing some
 663   // views for other objects.
 664   if (this->object_count_ > 1)
 665     return;
 666
 667   for (Views::iterator p = this->views_.begin();
 668        p != this->views_.end();
 669        ++p)
 670     p->second->clear_cache();
 671   for (Saved_views::iterator p = this->saved_views_.begin();
 672        p != this->saved_views_.end();
 673        ++p)
 674     (*p)->clear_cache();
 675 }
 676
 677 // Remove all the file views.  For a file which has multiple
 678 // associated objects (i.e., an archive), we keep accessed views
 679 // around until next time, in the hopes that they will be useful for
 680 // the next object.
 681
 682 void
 683 File_read::clear_views(bool destroying)
 684 {
 685   Views::iterator p = this->views_.begin();
 686   while (p != this->views_.end())
 687     {
 688       bool should_delete;
 689       if (p->second->is_locked())
 690         should_delete = false;
 691       else if (destroying)
 692         should_delete = true;
 693       else if (p->second->should_cache())
 694         should_delete = false;
 695       else if (this->object_count_ > 1 && p->second->accessed())
 696         should_delete = false;
 697       else
 698         should_delete = true;
 699
 700       if (should_delete)
 701         {
 702           delete p->second;
 703
 704           // map::erase invalidates only the iterator to the deleted
 705           // element.
 706           Views::iterator pe = p;
 707           ++p;
 708           this->views_.erase(pe);
 709         }
 710       else
 711         {
 712           gold_assert(!destroying);
 713           p->second->clear_accessed();
 714           ++p;
 715         }
 716     }
 717
 718   Saved_views::iterator q = this->saved_views_.begin();
 719   while (q != this->saved_views_.end())
 720     {
 721       if (!(*q)->is_locked())
 722         {
 723           delete *q;
 724           q = this->saved_views_.erase(q);
 725         }
 726       else
 727         {
 728           gold_assert(!destroying);
 729           ++q;
 730         }
 731     }
 732 }
 733
 734 // Print statistical information to stderr.  This is used for --stats.
 735
 736 void
 737 File_read::print_stats()
 738 {
 739   fprintf(stderr, _("%s: total bytes mapped for read: %llu\n"),
 740           program_name, File_read::total_mapped_bytes);
 741   fprintf(stderr, _("%s: maximum bytes mapped for read at one time: %llu\n"),
 742           program_name, File_read::maximum_mapped_bytes);
 743 }
 744
 745 // Class File_view.
 746
 747 File_view::~File_view()
 748 {
 749   gold_assert(this->file_.is_locked());
 750   this->view_->unlock();
 751 }
 752
 753 // Class Input_file.
 754
 755 // Create a file for testing.
 756
 757 Input_file::Input_file(const Task* task, const char* name,
 758                        const unsigned char* contents, off_t size)
 759   : file_()
 760 {
 761   this->input_argument_ =
 762     new Input_file_argument(name, Input_file_argument::INPUT_FILE_TYPE_FILE,
 763                             "", false, Position_dependent_options());
 764   bool ok = this->file_.open(task, name, contents, size);
 765   gold_assert(ok);
 766 }
 767
 768 // Return the position dependent options in force for this file.
 769
 770 const Position_dependent_options&
 771 Input_file::options() const
 772 {
 773   return this->input_argument_->options();
 774 }
 775
 776 // Return the name given by the user.  For -lc this will return "c".
 777
 778 const char*
 779 Input_file::name() const
 780 {
 781   return this->input_argument_->name();
 782 }
 783
 784 // Return whether this file is in a system directory.
 785
 786 bool
 787 Input_file::is_in_system_directory() const
 788 {
 789   if (this->is_in_sysroot())
 790     return true;
 791   return parameters->options().is_in_system_directory(this->filename());
 792 }
 793
 794 // Return whether we are only reading symbols.
 795
 796 bool
 797 Input_file::just_symbols() const
 798 {
 799   return this->input_argument_->just_symbols();
 800 }
 801
 802 // Return whether this is a file that we will search for in the list
 803 // of directories.
 804
 805 bool
 806 Input_file::will_search_for() const
 807 {
 808   return (!IS_ABSOLUTE_PATH(this->input_argument_->name())
 809           && (this->input_argument_->is_lib()
 810               || this->input_argument_->is_searched_file()
 811               || this->input_argument_->extra_search_path() != NULL));
 812 }
 813
 814 // Return the file last modification time.  Calls gold_fatal if the stat
 815 // system call failed.
 816
 817 Timespec
 818 File_read::get_mtime()
 819 {
 820   struct stat file_stat;
 821   this->reopen_descriptor();
 822
 823   if (fstat(this->descriptor_, &file_stat) < 0)
 824     gold_fatal(_("%s: stat failed: %s"), this->name_.c_str(),
 825                strerror(errno));
 826 #ifdef HAVE_STAT_ST_MTIM
 827   return Timespec(file_stat.st_mtim.tv_sec, file_stat.st_mtim.tv_nsec);
 828 #else
 829   return Timespec(file_stat.st_mtime, 0);
 830 #endif
 831 }
 832
 833 // Open the file.
 834
 835 // If the filename is not absolute, we assume it is in the current
 836 // directory *except* when:
 837 //    A) input_argument_->is_lib() is true;
 838 //    B) input_argument_->is_searched_file() is true; or
 839 //    C) input_argument_->extra_search_path() is not empty.
 840 // In each, we look in extra_search_path + library_path to find
 841 // the file location, rather than the current directory.
 842
 843 bool
 844 Input_file::open(const Dirsearch& dirpath, const Task* task, int *pindex)
 845 {
 846   std::string name;
 847
 848   // Case 1: name is an absolute file, just try to open it
 849   // Case 2: name is relative but is_lib is false, is_searched_file is false,
 850   //         and extra_search_path is empty
 851   if (IS_ABSOLUTE_PATH(this->input_argument_->name())
 852       || (!this->input_argument_->is_lib()
 853           && !this->input_argument_->is_searched_file()
 854           && this->input_argument_->extra_search_path() == NULL))
 855     {
 856       name = this->input_argument_->name();
 857       this->found_name_ = name;
 858     }
 859   // Case 3: is_lib is true or is_searched_file is true
 860   else if (this->input_argument_->is_lib()
 861            || this->input_argument_->is_searched_file())
 862     {
 863       // We don't yet support extra_search_path with -l.
 864       gold_assert(this->input_argument_->extra_search_path() == NULL);
 865       std::string n1, n2;
 866       if (this->input_argument_->is_lib())
 867         {
 868           n1 = "lib";
 869           n1 += this->input_argument_->name();
 870           if (parameters->options().is_static()
 871               || !this->input_argument_->options().Bdynamic())
 872             n1 += ".a";
 873           else
 874             {
 875               n2 = n1 + ".a";
 876               n1 += ".so";
 877             }
 878         }
 879       else
 880         n1 = this->input_argument_->name();
 881       name = dirpath.find(n1, n2, &this->is_in_sysroot_, pindex);
 882       if (name.empty())
 883         {
 884           gold_error(_("cannot find %s%s"),
 885                      this->input_argument_->is_lib() ? "-l" : "",
 886                      this->input_argument_->name());
 887           return false;
 888         }
 889       if (n2.empty() || name[name.length() - 1] == 'o')
 890         this->found_name_ = n1;
 891       else
 892         this->found_name_ = n2;
 893     }
 894   // Case 4: extra_search_path is not empty
 895   else
 896     {
 897       gold_assert(this->input_argument_->extra_search_path() != NULL);
 898
 899       // First, check extra_search_path.
 900       name = this->input_argument_->extra_search_path();
 901       if (!IS_DIR_SEPARATOR (name[name.length() - 1]))
 902         name += '/';
 903       name += this->input_argument_->name();
 904       struct stat dummy_stat;
 905       if (*pindex > 0 || ::stat(name.c_str(), &dummy_stat) < 0)
 906         {
 907           // extra_search_path failed, so check the normal search-path.
 908           int index = *pindex;
 909           if (index > 0)
 910             --index;
 911           name = dirpath.find(this->input_argument_->name(), "",
 912                               &this->is_in_sysroot_, &index);
 913           if (name.empty())
 914             {
 915               gold_error(_("cannot find %s"),
 916                          this->input_argument_->name());
 917               return false;
 918             }
 919           *pindex = index + 1;
 920         }
 921       this->found_name_ = this->input_argument_->name();
 922     }
 923
 924   // Now that we've figured out where the file lives, try to open it.
 925
 926   General_options::Object_format format =
 927     this->input_argument_->options().format_enum();
 928   bool ok;
 929   if (format == General_options::OBJECT_FORMAT_ELF)
 930     ok = this->file_.open(task, name);
 931   else
 932     {
 933       gold_assert(format == General_options::OBJECT_FORMAT_BINARY);
 934       ok = this->open_binary(task, name);
 935     }
 936
 937   if (!ok)
 938     {
 939       gold_error(_("cannot open %s: %s"),
 940                  name.c_str(), strerror(errno));
 941       return false;
 942     }
 943
 944   return true;
 945 }
 946
 947 // Open a file for --format binary.
 948
 949 bool
 950 Input_file::open_binary(const Task* task, const std::string& name)
 951 {
 952   // In order to open a binary file, we need machine code, size, and
 953   // endianness.  We may not have a valid target at this point, in
 954   // which case we use the default target.
 955   parameters_force_valid_target();
 956   const Target& target(parameters->target());
 957
 958   Binary_to_elf binary_to_elf(target.machine_code(),
 959                               target.get_size(),
 960                               target.is_big_endian(),
 961                               name);
 962   if (!binary_to_elf.convert(task))
 963     return false;
 964   return this->file_.open(task, name, binary_to_elf.converted_data_leak(),
 965                           binary_to_elf.converted_size());
 966 }
 967
 968 } // End namespace gold.