1// fileread.cc -- read files for gold 2 3// Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc. 4// Written by Ian Lance Taylor <iant@google.com>. 5 6// This file is part of gold. 7 8// This program is free software; you can redistribute it and/or modify 9// it under the terms of the GNU General Public License as published by 10// the Free Software Foundation; either version 3 of the License, or 11// (at your option) any later version. 12 13// This program is distributed in the hope that it will be useful, 14// but WITHOUT ANY WARRANTY; without even the implied warranty of 15// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16// GNU General Public License for more details. 17 18// You should have received a copy of the GNU General Public License 19// along with this program; if not, write to the Free Software 20// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 21// MA 02110-1301, USA. 22 23#include "gold.h" 24 25#include <cstring> 26#include <cerrno> 27#include <climits> 28#include <fcntl.h> 29#include <unistd.h> 30#include <sys/mman.h> 31 32#ifdef HAVE_READV 33#include <sys/uio.h> 34#endif 35 36#include <sys/stat.h> 37#include "filenames.h" 38 39#include "debug.h" 40#include "parameters.h" 41#include "options.h" 42#include "dirsearch.h" 43#include "target.h" 44#include "binary.h" 45#include "descriptors.h" 46#include "gold-threads.h" 47#include "fileread.h" 48 49#ifndef HAVE_READV 50struct iovec { void* iov_base; size_t iov_len; }; 51ssize_t 52readv(int, const iovec*, int) 53{ 54 gold_unreachable(); 55} 56#endif 57 58namespace gold 59{ 60 61// Class File_read::View. 62 63File_read::View::~View() 64{ 65 gold_assert(!this->is_locked()); 66 switch (this->data_ownership_) 67 { 68 case DATA_ALLOCATED_ARRAY: 69 delete[] this->data_; 70 break; 71 case DATA_MMAPPED: 72 if (::munmap(const_cast<unsigned char*>(this->data_), this->size_) != 0) 73 gold_warning(_("munmap failed: %s"), strerror(errno)); 74 File_read::current_mapped_bytes -= this->size_; 75 break; 76 case DATA_NOT_OWNED: 77 break; 78 default: 79 gold_unreachable(); 80 } 81} 82 83void 84File_read::View::lock() 85{ 86 ++this->lock_count_; 87} 88 89void 90File_read::View::unlock() 91{ 92 gold_assert(this->lock_count_ > 0); 93 --this->lock_count_; 94} 95 96bool 97File_read::View::is_locked() 98{ 99 return this->lock_count_ > 0; 100} 101 102// Class File_read. 103 104// A lock for the File_read static variables. 105static Lock* file_counts_lock = NULL; 106static Initialize_lock file_counts_initialize_lock(&file_counts_lock); 107 108// The File_read static variables. 109unsigned long long File_read::total_mapped_bytes; 110unsigned long long File_read::current_mapped_bytes; 111unsigned long long File_read::maximum_mapped_bytes; 112 113File_read::~File_read() 114{ 115 gold_assert(this->token_.is_writable()); 116 if (this->is_descriptor_opened_) 117 { 118 release_descriptor(this->descriptor_, true); 119 this->descriptor_ = -1; 120 this->is_descriptor_opened_ = false; 121 } 122 this->name_.clear(); 123 this->clear_views(CLEAR_VIEWS_ALL); 124} 125 126// Open the file. 127 128bool 129File_read::open(const Task* task, const std::string& name) 130{ 131 gold_assert(this->token_.is_writable() 132 && this->descriptor_ < 0 133 && !this->is_descriptor_opened_ 134 && this->name_.empty()); 135 this->name_ = name; 136 137 this->descriptor_ = open_descriptor(-1, this->name_.c_str(), 138 O_RDONLY); 139 140 if (this->descriptor_ >= 0) 141 { 142 this->is_descriptor_opened_ = true; 143 struct stat s; 144 if (::fstat(this->descriptor_, &s) < 0) 145 gold_error(_("%s: fstat failed: %s"), 146 this->name_.c_str(), strerror(errno)); 147 this->size_ = s.st_size; 148 gold_debug(DEBUG_FILES, "Attempt to open %s succeeded", 149 this->name_.c_str()); 150 this->token_.add_writer(task); 151 } 152 153 return this->descriptor_ >= 0; 154} 155 156// Open the file with the contents in memory. 157 158bool 159File_read::open(const Task* task, const std::string& name, 160 const unsigned char* contents, off_t size) 161{ 162 gold_assert(this->token_.is_writable() 163 && this->descriptor_ < 0 164 && !this->is_descriptor_opened_ 165 && this->name_.empty()); 166 this->name_ = name; 167 this->whole_file_view_ = new View(0, size, contents, 0, false, 168 View::DATA_NOT_OWNED); 169 this->add_view(this->whole_file_view_); 170 this->size_ = size; 171 this->token_.add_writer(task); 172 return true; 173} 174 175// Reopen a descriptor if necessary. 176 177void 178File_read::reopen_descriptor() 179{ 180 if (!this->is_descriptor_opened_) 181 { 182 this->descriptor_ = open_descriptor(this->descriptor_, 183 this->name_.c_str(), 184 O_RDONLY); 185 if (this->descriptor_ < 0) 186 gold_fatal(_("could not reopen file %s"), this->name_.c_str()); 187 this->is_descriptor_opened_ = true; 188 } 189} 190 191// Release the file. This is called when we are done with the file in 192// a Task. 193 194void 195File_read::release() 196{ 197 gold_assert(this->is_locked()); 198 199 if (!parameters->options_valid() || parameters->options().stats()) 200 { 201 file_counts_initialize_lock.initialize(); 202 Hold_optional_lock hl(file_counts_lock); 203 File_read::total_mapped_bytes += this->mapped_bytes_; 204 File_read::current_mapped_bytes += this->mapped_bytes_; 205 if (File_read::current_mapped_bytes > File_read::maximum_mapped_bytes) 206 File_read::maximum_mapped_bytes = File_read::current_mapped_bytes; 207 } 208 209 this->mapped_bytes_ = 0; 210 211 // Only clear views if there is only one attached object. Otherwise 212 // we waste time trying to clear cached archive views. Similarly 213 // for releasing the descriptor. 214 if (this->object_count_ <= 1) 215 { 216 this->clear_views(CLEAR_VIEWS_NORMAL); 217 if (this->is_descriptor_opened_) 218 { 219 release_descriptor(this->descriptor_, false); 220 this->is_descriptor_opened_ = false; 221 } 222 } 223 224 this->released_ = true; 225} 226 227// Lock the file. 228 229void 230File_read::lock(const Task* task) 231{ 232 gold_assert(this->released_); 233 this->token_.add_writer(task); 234 this->released_ = false; 235} 236 237// Unlock the file. 238 239void 240File_read::unlock(const Task* task) 241{ 242 this->release(); 243 this->token_.remove_writer(task); 244} 245 246// Return whether the file is locked. 247 248bool 249File_read::is_locked() const 250{ 251 if (!this->token_.is_writable()) 252 return true; 253 // The file is not locked, so it should have been released. 254 gold_assert(this->released_); 255 return false; 256} 257 258// See if we have a view which covers the file starting at START for 259// SIZE bytes. Return a pointer to the View if found, NULL if not. 260// If BYTESHIFT is not -1U, the returned View must have the specified 261// byte shift; otherwise, it may have any byte shift. If VSHIFTED is 262// not NULL, this sets *VSHIFTED to a view which would have worked if 263// not for the requested BYTESHIFT. 264 265inline File_read::View* 266File_read::find_view(off_t start, section_size_type size, 267 unsigned int byteshift, File_read::View** vshifted) const 268{ 269 if (vshifted != NULL) 270 *vshifted = NULL; 271 272 // If we have the whole file mmapped, and the alignment is right, 273 // we can return it. 274 if (this->whole_file_view_) 275 if (byteshift == -1U || byteshift == 0) 276 return this->whole_file_view_; 277 278 off_t page = File_read::page_offset(start); 279 280 unsigned int bszero = 0; 281 Views::const_iterator p = this->views_.upper_bound(std::make_pair(page - 1, 282 bszero)); 283 284 while (p != this->views_.end() && p->first.first <= page) 285 { 286 if (p->second->start() <= start 287 && (p->second->start() + static_cast<off_t>(p->second->size()) 288 >= start + static_cast<off_t>(size))) 289 { 290 if (byteshift == -1U || byteshift == p->second->byteshift()) 291 { 292 p->second->set_accessed(); 293 return p->second; 294 } 295 296 if (vshifted != NULL && *vshifted == NULL) 297 *vshifted = p->second; 298 } 299 300 ++p; 301 } 302 303 return NULL; 304} 305 306// Read SIZE bytes from the file starting at offset START. Read into 307// the buffer at P. 308 309void 310File_read::do_read(off_t start, section_size_type size, void* p) 311{ 312 ssize_t bytes; 313 if (this->whole_file_view_ != NULL) 314 { 315 bytes = this->size_ - start; 316 if (static_cast<section_size_type>(bytes) >= size) 317 { 318 memcpy(p, this->whole_file_view_->data() + start, size); 319 return; 320 } 321 } 322 else 323 { 324 this->reopen_descriptor(); 325 bytes = ::pread(this->descriptor_, p, size, start); 326 if (static_cast<section_size_type>(bytes) == size) 327 return; 328 329 if (bytes < 0) 330 { 331 gold_fatal(_("%s: pread failed: %s"), 332 this->filename().c_str(), strerror(errno)); 333 return; 334 } 335 } 336 337 gold_fatal(_("%s: file too short: read only %lld of %lld bytes at %lld"), 338 this->filename().c_str(), 339 static_cast<long long>(bytes), 340 static_cast<long long>(size), 341 static_cast<long long>(start)); 342} 343 344// Read data from the file. 345 346void 347File_read::read(off_t start, section_size_type size, void* p) 348{ 349 const File_read::View* pv = this->find_view(start, size, -1U, NULL); 350 if (pv != NULL) 351 { 352 memcpy(p, pv->data() + (start - pv->start() + pv->byteshift()), size); 353 return; 354 } 355 356 this->do_read(start, size, p); 357} 358 359// Add a new view. There may already be an existing view at this 360// offset. If there is, the new view will be larger, and should 361// replace the old view. 362 363void 364File_read::add_view(File_read::View* v) 365{ 366 std::pair<Views::iterator, bool> ins = 367 this->views_.insert(std::make_pair(std::make_pair(v->start(), 368 v->byteshift()), 369 v)); 370 if (ins.second) 371 return; 372 373 // There was an existing view at this offset. It must not be large 374 // enough. We can't delete it here, since something might be using 375 // it; we put it on a list to be deleted when the file is unlocked. 376 File_read::View* vold = ins.first->second; 377 gold_assert(vold->size() < v->size()); 378 if (vold->should_cache()) 379 { 380 v->set_cache(); 381 vold->clear_cache(); 382 } 383 this->saved_views_.push_back(vold); 384 385 ins.first->second = v; 386} 387 388// Make a new view with a specified byteshift, reading the data from 389// the file. 390 391File_read::View* 392File_read::make_view(off_t start, section_size_type size, 393 unsigned int byteshift, bool cache) 394{ 395 gold_assert(size > 0); 396 397 // Check that start and end of the view are within the file. 398 if (start > this->size_ 399 || (static_cast<unsigned long long>(size) 400 > static_cast<unsigned long long>(this->size_ - start))) 401 gold_fatal(_("%s: attempt to map %lld bytes at offset %lld exceeds " 402 "size of file; the file may be corrupt"), 403 this->filename().c_str(), 404 static_cast<long long>(size), 405 static_cast<long long>(start)); 406 407 off_t poff = File_read::page_offset(start); 408 409 section_size_type psize = File_read::pages(size + (start - poff)); 410 411 if (poff + static_cast<off_t>(psize) >= this->size_) 412 { 413 psize = this->size_ - poff; 414 gold_assert(psize >= size); 415 } 416 417 File_read::View* v; 418 if (byteshift != 0) 419 { 420 unsigned char* p = new unsigned char[psize + byteshift]; 421 memset(p, 0, byteshift); 422 this->do_read(poff, psize, p + byteshift); 423 v = new File_read::View(poff, psize, p, byteshift, cache, 424 View::DATA_ALLOCATED_ARRAY); 425 } 426 else 427 { 428 this->reopen_descriptor(); 429 void* p = ::mmap(NULL, psize, PROT_READ, MAP_PRIVATE, 430 this->descriptor_, poff); 431 if (p == MAP_FAILED) 432 gold_fatal(_("%s: mmap offset %lld size %lld failed: %s"), 433 this->filename().c_str(), 434 static_cast<long long>(poff), 435 static_cast<long long>(psize), 436 strerror(errno)); 437 438 this->mapped_bytes_ += psize; 439 440 const unsigned char* pbytes = static_cast<const unsigned char*>(p); 441 v = new File_read::View(poff, psize, pbytes, 0, cache, 442 View::DATA_MMAPPED); 443 } 444 445 this->add_view(v); 446 447 return v; 448} 449 450// Find a View or make a new one, shifted as required by the file 451// offset OFFSET and ALIGNED. 452 453File_read::View* 454File_read::find_or_make_view(off_t offset, off_t start, 455 section_size_type size, bool aligned, bool cache) 456{ 457 unsigned int byteshift; 458 if (offset == 0) 459 byteshift = 0; 460 else 461 { 462 unsigned int target_size = (!parameters->target_valid() 463 ? 64 464 : parameters->target().get_size()); 465 byteshift = offset & ((target_size / 8) - 1); 466 467 // Set BYTESHIFT to the number of dummy bytes which must be 468 // inserted before the data in order for this data to be 469 // aligned. 470 if (byteshift != 0) 471 byteshift = (target_size / 8) - byteshift; 472 } 473 474 // If --map-whole-files is set, make sure we have a 475 // whole file view. Options may not yet be ready, e.g., 476 // when reading a version script. We then default to 477 // --no-map-whole-files. 478 if (this->whole_file_view_ == NULL 479 && parameters->options_valid() 480 && parameters->options().map_whole_files()) 481 this->whole_file_view_ = this->make_view(0, this->size_, 0, cache); 482 483 // Try to find a View with the required BYTESHIFT. 484 File_read::View* vshifted; 485 File_read::View* v = this->find_view(offset + start, size, 486 aligned ? byteshift : -1U, 487 &vshifted); 488 if (v != NULL) 489 { 490 if (cache) 491 v->set_cache(); 492 return v; 493 } 494 495 // If VSHIFTED is not NULL, then it has the data we need, but with 496 // the wrong byteshift. 497 v = vshifted; 498 if (v != NULL) 499 { 500 gold_assert(aligned); 501 502 unsigned char* pbytes = new unsigned char[v->size() + byteshift]; 503 memset(pbytes, 0, byteshift); 504 memcpy(pbytes + byteshift, v->data() + v->byteshift(), v->size()); 505 506 File_read::View* shifted_view = 507 new File_read::View(v->start(), v->size(), pbytes, byteshift, 508 cache, View::DATA_ALLOCATED_ARRAY); 509 510 this->add_view(shifted_view); 511 return shifted_view; 512 } 513 514 // Make a new view. If we don't need an aligned view, use a 515 // byteshift of 0, so that we can use mmap. 516 return this->make_view(offset + start, size, 517 aligned ? byteshift : 0, 518 cache); 519} 520 521// Get a view into the file. 522 523const unsigned char* 524File_read::get_view(off_t offset, off_t start, section_size_type size, 525 bool aligned, bool cache) 526{ 527 File_read::View* pv = this->find_or_make_view(offset, start, size, 528 aligned, cache); 529 return pv->data() + (offset + start - pv->start() + pv->byteshift()); 530} 531 532File_view* 533File_read::get_lasting_view(off_t offset, off_t start, section_size_type size, 534 bool aligned, bool cache) 535{ 536 File_read::View* pv = this->find_or_make_view(offset, start, size, 537 aligned, cache); 538 pv->lock(); 539 return new File_view(*this, pv, 540 (pv->data() 541 + (offset + start - pv->start() + pv->byteshift()))); 542} 543 544// Use readv to read COUNT entries from RM starting at START. BASE 545// must be added to all file offsets in RM. 546 547void 548File_read::do_readv(off_t base, const Read_multiple& rm, size_t start, 549 size_t count) 550{ 551 unsigned char discard[File_read::page_size]; 552 iovec iov[File_read::max_readv_entries * 2]; 553 size_t iov_index = 0; 554 555 off_t first_offset = rm[start].file_offset; 556 off_t last_offset = first_offset; 557 ssize_t want = 0; 558 for (size_t i = 0; i < count; ++i) 559 { 560 const Read_multiple_entry& i_entry(rm[start + i]); 561 562 if (i_entry.file_offset > last_offset) 563 { 564 size_t skip = i_entry.file_offset - last_offset; 565 gold_assert(skip <= sizeof discard); 566 567 iov[iov_index].iov_base = discard; 568 iov[iov_index].iov_len = skip; 569 ++iov_index; 570 571 want += skip; 572 } 573 574 iov[iov_index].iov_base = i_entry.buffer; 575 iov[iov_index].iov_len = i_entry.size; 576 ++iov_index; 577 578 want += i_entry.size; 579 580 last_offset = i_entry.file_offset + i_entry.size; 581 } 582 583 this->reopen_descriptor(); 584 585 gold_assert(iov_index < sizeof iov / sizeof iov[0]); 586 587 if (::lseek(this->descriptor_, base + first_offset, SEEK_SET) < 0) 588 gold_fatal(_("%s: lseek failed: %s"), 589 this->filename().c_str(), strerror(errno)); 590 591 ssize_t got = ::readv(this->descriptor_, iov, iov_index); 592 593 if (got < 0) 594 gold_fatal(_("%s: readv failed: %s"), 595 this->filename().c_str(), strerror(errno)); 596 if (got != want) 597 gold_fatal(_("%s: file too short: read only %zd of %zd bytes at %lld"), 598 this->filename().c_str(), 599 got, want, static_cast<long long>(base + first_offset)); 600} 601 602// Portable IOV_MAX. 603 604#if !defined(HAVE_READV) 605#define GOLD_IOV_MAX 1 606#elif defined(IOV_MAX) 607#define GOLD_IOV_MAX IOV_MAX 608#else 609#define GOLD_IOV_MAX (File_read::max_readv_entries * 2) 610#endif 611 612// Read several pieces of data from the file. 613 614void 615File_read::read_multiple(off_t base, const Read_multiple& rm) 616{ 617 static size_t iov_max = GOLD_IOV_MAX; 618 size_t count = rm.size(); 619 size_t i = 0; 620 while (i < count) 621 { 622 // Find up to MAX_READV_ENTRIES consecutive entries which are 623 // less than one page apart. 624 const Read_multiple_entry& i_entry(rm[i]); 625 off_t i_off = i_entry.file_offset; 626 off_t end_off = i_off + i_entry.size; 627 size_t j; 628 for (j = i + 1; j < count; ++j) 629 { 630 if (j - i >= File_read::max_readv_entries || j - i >= iov_max / 2) 631 break; 632 const Read_multiple_entry& j_entry(rm[j]); 633 off_t j_off = j_entry.file_offset; 634 gold_assert(j_off >= end_off); 635 off_t j_end_off = j_off + j_entry.size; 636 if (j_end_off - end_off >= File_read::page_size) 637 break; 638 end_off = j_end_off; 639 } 640 641 if (j == i + 1) 642 this->read(base + i_off, i_entry.size, i_entry.buffer); 643 else 644 { 645 File_read::View* view = this->find_view(base + i_off, 646 end_off - i_off, 647 -1U, NULL); 648 if (view == NULL) 649 this->do_readv(base, rm, i, j - i); 650 else 651 { 652 const unsigned char* v = (view->data() 653 + (base + i_off - view->start() 654 + view->byteshift())); 655 for (size_t k = i; k < j; ++k) 656 { 657 const Read_multiple_entry& k_entry(rm[k]); 658 gold_assert((convert_to_section_size_type(k_entry.file_offset 659 - i_off) 660 + k_entry.size) 661 <= convert_to_section_size_type(end_off 662 - i_off)); 663 memcpy(k_entry.buffer, 664 v + (k_entry.file_offset - i_off), 665 k_entry.size); 666 } 667 } 668 } 669 670 i = j; 671 } 672} 673 674// Mark all views as no longer cached. 675 676void 677File_read::clear_view_cache_marks() 678{ 679 // Just ignore this if there are multiple objects associated with 680 // the file. Otherwise we will wind up uncaching and freeing some 681 // views for other objects. 682 if (this->object_count_ > 1) 683 return; 684 685 for (Views::iterator p = this->views_.begin(); 686 p != this->views_.end(); 687 ++p) 688 p->second->clear_cache(); 689 for (Saved_views::iterator p = this->saved_views_.begin(); 690 p != this->saved_views_.end(); 691 ++p) 692 (*p)->clear_cache(); 693} 694 695// Remove all the file views. For a file which has multiple 696// associated objects (i.e., an archive), we keep accessed views 697// around until next time, in the hopes that they will be useful for 698// the next object. 699 700void 701File_read::clear_views(Clear_views_mode mode) 702{ 703 bool keep_files_mapped = (parameters->options_valid() 704 && parameters->options().keep_files_mapped()); 705 Views::iterator p = this->views_.begin(); 706 while (p != this->views_.end()) 707 { 708 bool should_delete; 709 if (p->second->is_locked() || p->second->is_permanent_view()) 710 should_delete = false; 711 else if (mode == CLEAR_VIEWS_ALL) 712 should_delete = true; 713 else if (p->second->should_cache() && keep_files_mapped) 714 should_delete = false; 715 else if (this->object_count_ > 1 716 && p->second->accessed() 717 && mode != CLEAR_VIEWS_ARCHIVE) 718 should_delete = false; 719 else 720 should_delete = true; 721 722 if (should_delete) 723 { 724 if (p->second == this->whole_file_view_) 725 this->whole_file_view_ = NULL; 726 delete p->second; 727 728 // map::erase invalidates only the iterator to the deleted 729 // element. 730 Views::iterator pe = p; 731 ++p; 732 this->views_.erase(pe); 733 } 734 else 735 { 736 p->second->clear_accessed(); 737 ++p; 738 } 739 } 740 741 Saved_views::iterator q = this->saved_views_.begin(); 742 while (q != this->saved_views_.end()) 743 { 744 if (!(*q)->is_locked()) 745 { 746 delete *q; 747 q = this->saved_views_.erase(q); 748 } 749 else 750 { 751 gold_assert(mode != CLEAR_VIEWS_ALL); 752 ++q; 753 } 754 } 755} 756 757// Print statistical information to stderr. This is used for --stats. 758 759void 760File_read::print_stats() 761{ 762 fprintf(stderr, _("%s: total bytes mapped for read: %llu\n"), 763 program_name, File_read::total_mapped_bytes); 764 fprintf(stderr, _("%s: maximum bytes mapped for read at one time: %llu\n"), 765 program_name, File_read::maximum_mapped_bytes); 766} 767 768// Class File_view. 769 770File_view::~File_view() 771{ 772 gold_assert(this->file_.is_locked()); 773 this->view_->unlock(); 774} 775 776// Class Input_file. 777 778// Create a file for testing. 779 780Input_file::Input_file(const Task* task, const char* name, 781 const unsigned char* contents, off_t size) 782 : file_() 783{ 784 this->input_argument_ = 785 new Input_file_argument(name, Input_file_argument::INPUT_FILE_TYPE_FILE, 786 "", false, Position_dependent_options()); 787 bool ok = this->file_.open(task, name, contents, size); 788 gold_assert(ok); 789} 790 791// Return the position dependent options in force for this file. 792 793const Position_dependent_options& 794Input_file::options() const 795{ 796 return this->input_argument_->options(); 797} 798 799// Return the name given by the user. For -lc this will return "c". 800 801const char* 802Input_file::name() const 803{ 804 return this->input_argument_->name(); 805} 806 807// Return whether this file is in a system directory. 808 809bool 810Input_file::is_in_system_directory() const 811{ 812 if (this->is_in_sysroot()) 813 return true; 814 return parameters->options().is_in_system_directory(this->filename()); 815} 816 817// Return whether we are only reading symbols. 818 819bool 820Input_file::just_symbols() const 821{ 822 return this->input_argument_->just_symbols(); 823} 824 825// Return whether this is a file that we will search for in the list 826// of directories. 827 828bool 829Input_file::will_search_for() const 830{ 831 return (!IS_ABSOLUTE_PATH(this->input_argument_->name()) 832 && (this->input_argument_->is_lib() 833 || this->input_argument_->is_searched_file() 834 || this->input_argument_->extra_search_path() != NULL)); 835} 836 837// Return the file last modification time. Calls gold_fatal if the stat 838// system call failed. 839 840Timespec 841File_read::get_mtime() 842{ 843 struct stat file_stat; 844 this->reopen_descriptor(); 845 846 if (fstat(this->descriptor_, &file_stat) < 0) 847 gold_fatal(_("%s: stat failed: %s"), this->name_.c_str(), 848 strerror(errno)); 849#ifdef HAVE_STAT_ST_MTIM 850 return Timespec(file_stat.st_mtim.tv_sec, file_stat.st_mtim.tv_nsec); 851#else 852 return Timespec(file_stat.st_mtime, 0); 853#endif 854} 855 856// Try to find a file in the extra search dirs. Returns true on success. 857 858bool 859Input_file::try_extra_search_path(int* pindex, 860 const Input_file_argument* input_argument, 861 std::string filename, std::string* found_name, 862 std::string* namep) 863{ 864 if (input_argument->extra_search_path() == NULL) 865 return false; 866 867 std::string name = input_argument->extra_search_path(); 868 if (!IS_DIR_SEPARATOR(name[name.length() - 1])) 869 name += '/'; 870 name += filename; 871 872 struct stat dummy_stat; 873 if (*pindex > 0 || ::stat(name.c_str(), &dummy_stat) < 0) 874 return false; 875 876 *found_name = filename; 877 *namep = name; 878 return true; 879} 880 881// Find the actual file. 882// If the filename is not absolute, we assume it is in the current 883// directory *except* when: 884// A) input_argument_->is_lib() is true; 885// B) input_argument_->is_searched_file() is true; or 886// C) input_argument_->extra_search_path() is not empty. 887// In each, we look in extra_search_path + library_path to find 888// the file location, rather than the current directory. 889 890bool 891Input_file::find_file(const Dirsearch& dirpath, int* pindex, 892 const Input_file_argument* input_argument, 893 bool* is_in_sysroot, 894 std::string* found_name, std::string* namep) 895{ 896 std::string name; 897 898 // Case 1: name is an absolute file, just try to open it 899 // Case 2: name is relative but is_lib is false, is_searched_file is false, 900 // and extra_search_path is empty 901 if (IS_ABSOLUTE_PATH(input_argument->name()) 902 || (!input_argument->is_lib() 903 && !input_argument->is_searched_file() 904 && input_argument->extra_search_path() == NULL)) 905 { 906 name = input_argument->name(); 907 *found_name = name; 908 *namep = name; 909 return true; 910 } 911 // Case 3: is_lib is true or is_searched_file is true 912 else if (input_argument->is_lib() 913 || input_argument->is_searched_file()) 914 { 915 std::string n1, n2; 916 if (input_argument->is_lib()) 917 { 918 n1 = "lib"; 919 n1 += input_argument->name(); 920 if (parameters->options().is_static() 921 || !input_argument->options().Bdynamic()) 922 n1 += ".a"; 923 else 924 { 925 n2 = n1 + ".a"; 926 n1 += ".so"; 927 } 928 } 929 else 930 n1 = input_argument->name(); 931 932 if (Input_file::try_extra_search_path(pindex, input_argument, n1, 933 found_name, namep)) 934 return true; 935 936 if (!n2.empty() && Input_file::try_extra_search_path(pindex, 937 input_argument, n2, 938 found_name, namep)) 939 return true; 940 941 // It is not in the extra_search_path. 942 name = dirpath.find(n1, n2, is_in_sysroot, pindex); 943 if (name.empty()) 944 { 945 gold_error(_("cannot find %s%s"), 946 input_argument->is_lib() ? "-l" : "", 947 input_argument->name()); 948 return false; 949 } 950 if (n2.empty() || name[name.length() - 1] == 'o') 951 *found_name = n1; 952 else 953 *found_name = n2; 954 *namep = name; 955 return true; 956 } 957 // Case 4: extra_search_path is not empty 958 else 959 { 960 gold_assert(input_argument->extra_search_path() != NULL); 961 962 if (try_extra_search_path(pindex, input_argument, input_argument->name(), 963 found_name, namep)) 964 return true; 965 966 // extra_search_path failed, so check the normal search-path. 967 int index = *pindex; 968 if (index > 0) 969 --index; 970 name = dirpath.find(input_argument->name(), "", 971 is_in_sysroot, &index); 972 if (name.empty()) 973 { 974 gold_error(_("cannot find %s"), 975 input_argument->name()); 976 return false; 977 } 978 *found_name = input_argument->name(); 979 *namep = name; 980 *pindex = index + 1; 981 return true; 982 } 983} 984 985// Open the file. 986 987bool 988Input_file::open(const Dirsearch& dirpath, const Task* task, int* pindex) 989{ 990 std::string name; 991 if (!Input_file::find_file(dirpath, pindex, this->input_argument_, 992 &this->is_in_sysroot_, &this->found_name_, &name)) 993 return false; 994 995 // Now that we've figured out where the file lives, try to open it. 996 997 General_options::Object_format format = 998 this->input_argument_->options().format_enum(); 999 bool ok; 1000 if (format == General_options::OBJECT_FORMAT_ELF) 1001 { 1002 ok = this->file_.open(task, name); 1003 this->format_ = FORMAT_ELF; 1004 } 1005 else 1006 { 1007 gold_assert(format == General_options::OBJECT_FORMAT_BINARY); 1008 ok = this->open_binary(task, name); 1009 this->format_ = FORMAT_BINARY; 1010 } 1011 1012 if (!ok) 1013 { 1014 gold_error(_("cannot open %s: %s"), 1015 name.c_str(), strerror(errno)); 1016 this->format_ = FORMAT_NONE; 1017 return false; 1018 } 1019 1020 return true; 1021} 1022 1023// Open a file for --format binary. 1024 1025bool 1026Input_file::open_binary(const Task* task, const std::string& name) 1027{ 1028 // In order to open a binary file, we need machine code, size, and 1029 // endianness. We may not have a valid target at this point, in 1030 // which case we use the default target. 1031 parameters_force_valid_target(); 1032 const Target& target(parameters->target()); 1033 1034 Binary_to_elf binary_to_elf(target.machine_code(), 1035 target.get_size(), 1036 target.is_big_endian(), 1037 name); 1038 if (!binary_to_elf.convert(task)) 1039 return false; 1040 return this->file_.open(task, name, binary_to_elf.converted_data_leak(), 1041 binary_to_elf.converted_size()); 1042} 1043 1044} // End namespace gold. 1045