1 // fileread.cc -- read files for gold
3 // Copyright 2006, 2007 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
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.
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.
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.
30 #include "filenames.h"
33 #include "dirsearch.h"
39 // Class File_read::View.
41 File_read::View::~View()
43 gold_assert(!this->is_locked());
48 if (::munmap(const_cast<unsigned char*>(this->data_), this->size_) != 0)
49 fprintf(stderr, _("%s: munmap failed: %s\n"),
50 program_name, strerror(errno));
55 File_read::View::lock()
61 File_read::View::unlock()
63 gold_assert(this->lock_count_ > 0);
68 File_read::View::is_locked()
70 return this->lock_count_ > 0;
75 // The File_read class is designed to support file descriptor caching,
76 // but this is not currently implemented.
78 File_read::~File_read()
80 gold_assert(this->lock_count_ == 0);
81 if (this->descriptor_ >= 0)
83 if (close(this->descriptor_) < 0)
84 fprintf(stderr, _("%s: warning: close(%s) failed: %s"),
85 program_name, this->name_.c_str(), strerror(errno));
86 this->descriptor_ = -1;
89 this->clear_views(true);
95 File_read::open(const std::string& name)
97 gold_assert(this->lock_count_ == 0
98 && this->descriptor_ < 0
99 && this->name_.empty());
102 this->descriptor_ = ::open(this->name_.c_str(), O_RDONLY);
104 if (this->descriptor_ >= 0)
107 if (::fstat(this->descriptor_, &s) < 0)
109 fprintf(stderr, _("%s: %s: fstat failed: %s"), program_name,
110 this->name_.c_str(), strerror(errno));
113 this->size_ = s.st_size;
118 return this->descriptor_ >= 0;
121 // Open the file for testing purposes.
124 File_read::open(const std::string& name, const unsigned char* contents,
127 gold_assert(this->lock_count_ == 0
128 && this->descriptor_ < 0
129 && this->name_.empty());
131 this->contents_ = contents;
146 gold_assert(this->lock_count_ > 0);
148 if (this->lock_count_ == 0)
149 this->clear_views(false);
153 File_read::is_locked()
155 return this->lock_count_ > 0;
158 // See if we have a view which covers the file starting at START for
159 // SIZE bytes. Return a pointer to the View if found, NULL if not.
161 inline File_read::View*
162 File_read::find_view(off_t start, off_t size)
164 off_t page = File_read::page_offset(start);
165 Views::iterator p = this->views_.find(page);
166 if (p == this->views_.end())
168 if (p->second->size() - (start - page) < size)
173 // Read SIZE bytes from the file starting at offset START. Read into
177 File_read::do_read(off_t start, off_t size, void* p)
179 gold_assert(this->lock_count_ > 0);
182 if (this->contents_ != NULL)
184 bytes = this->size_ - start;
187 memcpy(p, this->contents_ + start, size);
193 bytes = ::pread(this->descriptor_, p, size, start);
199 fprintf(stderr, _("%s: %s: pread failed: %s\n"),
200 program_name, this->filename().c_str(), strerror(errno));
206 _("%s: %s: file too short: read only %lld of %lld bytes at %lld\n"),
207 program_name, this->filename().c_str(),
208 static_cast<long long>(bytes),
209 static_cast<long long>(size),
210 static_cast<long long>(start));
214 // Read data from the file.
217 File_read::read(off_t start, off_t size, void* p)
219 gold_assert(this->lock_count_ > 0);
221 File_read::View* pv = this->find_view(start, size);
224 memcpy(p, pv->data() + (start - pv->start()), size);
228 this->do_read(start, size, p);
231 // Find an existing view or make a new one.
234 File_read::find_or_make_view(off_t start, off_t size, bool cache)
236 gold_assert(this->lock_count_ > 0);
238 off_t poff = File_read::page_offset(start);
240 File_read::View* const vnull = NULL;
241 std::pair<Views::iterator, bool> ins =
242 this->views_.insert(std::make_pair(poff, vnull));
246 // There was an existing view at this offset.
247 File_read::View* v = ins.first->second;
248 if (v->size() - (start - v->start()) >= size)
255 // This view is not large enough.
256 this->saved_views_.push_back(v);
259 // We need to read data from the file. We read full pages for
260 // greater efficiency on small files.
262 off_t psize = File_read::pages(size + (start - poff));
264 if (poff + psize >= this->size_)
266 psize = this->size_ - poff;
267 gold_assert(psize >= size);
272 if (this->contents_ != NULL)
274 unsigned char* p = new unsigned char[psize];
275 this->do_read(poff, psize, p);
276 v = new File_read::View(poff, psize, p, cache, false);
280 void* p = ::mmap(NULL, psize, PROT_READ, MAP_SHARED,
281 this->descriptor_, poff);
284 fprintf(stderr, _("%s: %s: mmap offset %lld size %lld failed: %s\n"),
285 program_name, this->filename().c_str(),
286 static_cast<long long>(poff),
287 static_cast<long long>(psize),
292 const unsigned char* pbytes = static_cast<const unsigned char*>(p);
293 v = new File_read::View(poff, psize, pbytes, cache, true);
296 ins.first->second = v;
300 // This implementation of get_view just reads into a memory buffer,
301 // which we store on view_list_. At some point we should support
305 File_read::get_view(off_t start, off_t size, bool cache)
307 gold_assert(this->lock_count_ > 0);
308 File_read::View* pv = this->find_or_make_view(start, size, cache);
309 return pv->data() + (start - pv->start());
313 File_read::get_lasting_view(off_t start, off_t size, bool cache)
315 gold_assert(this->lock_count_ > 0);
316 File_read::View* pv = this->find_or_make_view(start, size, cache);
318 return new File_view(*this, pv, pv->data() + (start - pv->start()));
321 // Remove all the file views.
324 File_read::clear_views(bool destroying)
326 for (Views::iterator p = this->views_.begin();
327 p != this->views_.end();
330 if (!p->second->is_locked()
331 && (destroying || !p->second->should_cache()))
335 gold_assert(!destroying);
336 this->saved_views_.push_back(p->second);
339 this->views_.clear();
341 Saved_views::iterator p = this->saved_views_.begin();
342 while (p != this->saved_views_.end())
344 if (!(*p)->is_locked()
345 && (destroying || !(*p)->should_cache()))
348 p = this->saved_views_.erase(p);
352 gold_assert(!destroying);
360 File_view::~File_view()
362 gold_assert(this->file_.is_locked());
363 this->view_->unlock();
368 // Create a file for testing.
370 Input_file::Input_file(const char* name, const unsigned char* contents,
374 this->input_argument_ =
375 new Input_file_argument(name, false, "", Position_dependent_options());
376 bool ok = file_.open(name, contents, size);
382 // If the filename is not absolute, we assume it is in the current
383 // directory *except* when:
384 // A) input_argument_->is_lib() is true; or
385 // B) input_argument_->extra_search_path() is not empty.
386 // In both cases, we look in extra_search_path + library_path to find
387 // the file location, rather than the current directory.
390 Input_file::open(const General_options& options, const Dirsearch& dirpath)
394 // Case 1: name is an absolute file, just try to open it
395 // Case 2: name is relative but is_lib is false and extra_search_path
397 if (IS_ABSOLUTE_PATH (this->input_argument_->name())
398 || (!this->input_argument_->is_lib()
399 && this->input_argument_->extra_search_path() == NULL))
400 name = this->input_argument_->name();
402 // Case 3: is_lib is true
403 else if (this->input_argument_->is_lib())
405 // We don't yet support extra_search_path with -l.
406 gold_assert(this->input_argument_->extra_search_path() == NULL);
407 std::string n1("lib");
408 n1 += this->input_argument_->name();
410 if (options.is_static())
417 name = dirpath.find(n1, n2, &this->is_in_sysroot_);
420 fprintf(stderr, _("%s: cannot find -l%s\n"), program_name,
421 this->input_argument_->name());
426 // Case 4: extra_search_path is not empty
429 gold_assert(this->input_argument_->extra_search_path() != NULL);
431 // First, check extra_search_path.
432 name = this->input_argument_->extra_search_path();
433 if (!IS_DIR_SEPARATOR (name[name.length() - 1]))
435 name += this->input_argument_->name();
436 struct stat dummy_stat;
437 if (::stat(name.c_str(), &dummy_stat) < 0)
439 // extra_search_path failed, so check the normal search-path.
440 name = dirpath.find(this->input_argument_->name(), "",
441 &this->is_in_sysroot_);
444 fprintf(stderr, _("%s: cannot find %s\n"), program_name,
445 this->input_argument_->name());
451 // Now that we've figured out where the file lives, try to open it.
452 if (!this->file_.open(name))
454 fprintf(stderr, _("%s: cannot open %s: %s\n"), program_name,
455 name.c_str(), strerror(errno));
460 } // End namespace gold.