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.
32 #include "dirsearch.h"
38 // Class File_read::View.
40 File_read::View::~View()
42 gold_assert(!this->is_locked());
47 if (::munmap(const_cast<unsigned char*>(this->data_), this->size_) != 0)
48 fprintf(stderr, _("%s: munmap failed: %s\n"),
49 program_name, strerror(errno));
54 File_read::View::lock()
60 File_read::View::unlock()
62 gold_assert(this->lock_count_ > 0);
67 File_read::View::is_locked()
69 return this->lock_count_ > 0;
74 // The File_read class is designed to support file descriptor caching,
75 // but this is not currently implemented.
77 File_read::~File_read()
79 gold_assert(this->lock_count_ == 0);
80 if (this->descriptor_ >= 0)
82 if (close(this->descriptor_) < 0)
83 fprintf(stderr, _("%s: warning: close(%s) failed: %s"),
84 program_name, this->name_.c_str(), strerror(errno));
85 this->descriptor_ = -1;
88 this->clear_views(true);
94 File_read::open(const std::string& name)
96 gold_assert(this->lock_count_ == 0
97 && this->descriptor_ < 0
98 && this->name_.empty());
101 this->descriptor_ = ::open(this->name_.c_str(), O_RDONLY);
103 if (this->descriptor_ >= 0)
106 if (::fstat(this->descriptor_, &s) < 0)
108 fprintf(stderr, _("%s: %s: fstat failed: %s"), program_name,
109 this->name_.c_str(), strerror(errno));
112 this->size_ = s.st_size;
117 return this->descriptor_ >= 0;
120 // Open the file for testing purposes.
123 File_read::open(const std::string& name, const unsigned char* contents,
126 gold_assert(this->lock_count_ == 0
127 && this->descriptor_ < 0
128 && this->name_.empty());
130 this->contents_ = contents;
145 gold_assert(this->lock_count_ > 0);
147 if (this->lock_count_ == 0)
148 this->clear_views(false);
152 File_read::is_locked()
154 return this->lock_count_ > 0;
157 // See if we have a view which covers the file starting at START for
158 // SIZE bytes. Return a pointer to the View if found, NULL if not.
160 inline File_read::View*
161 File_read::find_view(off_t start, off_t size)
163 off_t page = File_read::page_offset(start);
164 Views::iterator p = this->views_.find(page);
165 if (p == this->views_.end())
167 if (p->second->size() - (start - page) < size)
172 // Read SIZE bytes from the file starting at offset START. Read into
176 File_read::do_read(off_t start, off_t size, void* p)
178 gold_assert(this->lock_count_ > 0);
181 if (this->contents_ != NULL)
183 bytes = this->size_ - start;
186 memcpy(p, this->contents_ + start, size);
192 bytes = ::pread(this->descriptor_, p, size, start);
198 fprintf(stderr, _("%s: %s: pread failed: %s\n"),
199 program_name, this->filename().c_str(), strerror(errno));
205 _("%s: %s: file too short: read only %lld of %lld bytes at %lld\n"),
206 program_name, this->filename().c_str(),
207 static_cast<long long>(bytes),
208 static_cast<long long>(size),
209 static_cast<long long>(start));
213 // Read data from the file.
216 File_read::read(off_t start, off_t size, void* p)
218 gold_assert(this->lock_count_ > 0);
220 File_read::View* pv = this->find_view(start, size);
223 memcpy(p, pv->data() + (start - pv->start()), size);
227 this->do_read(start, size, p);
230 // Find an existing view or make a new one.
233 File_read::find_or_make_view(off_t start, off_t size, bool cache)
235 gold_assert(this->lock_count_ > 0);
237 off_t poff = File_read::page_offset(start);
239 File_read::View* const vnull = NULL;
240 std::pair<Views::iterator, bool> ins =
241 this->views_.insert(std::make_pair(poff, vnull));
245 // There was an existing view at this offset.
246 File_read::View* v = ins.first->second;
247 if (v->size() - (start - v->start()) >= size)
254 // This view is not large enough.
255 this->saved_views_.push_back(v);
258 // We need to read data from the file. We read full pages for
259 // greater efficiency on small files.
261 off_t psize = File_read::pages(size + (start - poff));
263 if (poff + psize >= this->size_)
265 psize = this->size_ - poff;
266 gold_assert(psize >= size);
271 if (this->contents_ != NULL)
273 unsigned char* p = new unsigned char[psize];
274 this->do_read(poff, psize, p);
275 v = new File_read::View(poff, psize, p, cache, false);
279 void* p = ::mmap(NULL, psize, PROT_READ, MAP_SHARED,
280 this->descriptor_, poff);
283 fprintf(stderr, _("%s: %s: mmap offset %lld size %lld failed: %s\n"),
284 program_name, this->filename().c_str(),
285 static_cast<long long>(poff),
286 static_cast<long long>(psize),
291 const unsigned char* pbytes = static_cast<const unsigned char*>(p);
292 v = new File_read::View(poff, psize, pbytes, cache, true);
295 ins.first->second = v;
299 // This implementation of get_view just reads into a memory buffer,
300 // which we store on view_list_. At some point we should support
304 File_read::get_view(off_t start, off_t size, bool cache)
306 gold_assert(this->lock_count_ > 0);
307 File_read::View* pv = this->find_or_make_view(start, size, cache);
308 return pv->data() + (start - pv->start());
312 File_read::get_lasting_view(off_t start, off_t size, bool cache)
314 gold_assert(this->lock_count_ > 0);
315 File_read::View* pv = this->find_or_make_view(start, size, cache);
317 return new File_view(*this, pv, pv->data() + (start - pv->start()));
320 // Remove all the file views.
323 File_read::clear_views(bool destroying)
325 for (Views::iterator p = this->views_.begin();
326 p != this->views_.end();
329 if (!p->second->is_locked()
330 && (destroying || !p->second->should_cache()))
334 gold_assert(!destroying);
335 this->saved_views_.push_back(p->second);
338 this->views_.clear();
340 Saved_views::iterator p = this->saved_views_.begin();
341 while (p != this->saved_views_.end())
343 if (!(*p)->is_locked()
344 && (destroying || !(*p)->should_cache()))
347 p = this->saved_views_.erase(p);
351 gold_assert(!destroying);
359 File_view::~File_view()
361 gold_assert(this->file_.is_locked());
362 this->view_->unlock();
367 // Create a file for testing.
369 Input_file::Input_file(const char* name, const unsigned char* contents,
373 this->input_argument_ =
374 new Input_file_argument(name, false, Position_dependent_options());
375 bool ok = file_.open(name, contents, size);
382 Input_file::open(const General_options& options, const Dirsearch& dirpath)
385 if (!this->input_argument_->is_lib())
386 name = this->input_argument_->name();
389 std::string n1("lib");
390 n1 += this->input_argument_->name();
392 if (options.is_static())
399 name = dirpath.find(n1, n2);
402 fprintf(stderr, _("%s: cannot find %s\n"), program_name,
403 this->input_argument_->name());
408 if (!this->file_.open(name))
410 fprintf(stderr, _("%s: cannot open %s: %s\n"), program_name,
411 name.c_str(), strerror(errno));
416 } // End namespace gold.