1 // archive.h -- archive support for gold -*- C++ -*-
3 // Copyright 2006, 2007, 2008 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.
23 #ifndef GOLD_ARCHIVE_H
24 #define GOLD_ARCHIVE_H
30 #include "workqueue.h"
42 // This class represents an archive--generally a libNAME.a file.
43 // Archives have a symbol table and a list of objects.
48 Archive(const std::string& name, Input_file* input_file,
49 bool is_thin_archive, Dirsearch* dirpath, Task* task)
50 : name_(name), input_file_(input_file), armap_(), armap_names_(),
51 extended_names_(), armap_checked_(), seen_offsets_(),
52 is_thin_archive_(is_thin_archive), dirpath_(dirpath), task_(task)
55 // The length of the magic string at the start of an archive.
56 static const int sarmag = 8;
58 // The magic string at the start of an archive.
59 static const char armag[sarmag];
60 static const char armagt[sarmag];
62 // The string expected at the end of an archive member header.
63 static const char arfmag[2];
65 // The name of the object. This is the name used on the command
66 // line; e.g., if "-lgcc" is on the command line, this will be
70 { return this->name_; }
75 { return this->input_file_->filename(); }
77 // Set up the archive: read the symbol map.
81 // Get a reference to the underlying file.
84 { return this->input_file_->file(); }
88 { return this->input_file_->file(); }
90 // Lock the underlying file.
93 { this->input_file_->file().lock(t); }
95 // Unlock the underlying file.
98 { this->input_file_->file().unlock(t); }
100 // Return whether the underlying file is locked.
103 { return this->input_file_->file().is_locked(); }
105 // Return the token, so that the task can be queued.
108 { return this->input_file_->file().token(); }
110 // Release the underlying file.
113 { this->input_file_->file().release(); }
115 // Clear uncached views in the underlying file.
117 clear_uncached_views()
118 { this->input_file_->file().clear_uncached_views(); }
120 // Whether this is a thin archive.
122 is_thin_archive() const
123 { return this->is_thin_archive_; }
125 // Unlock any nested archives.
127 unlock_nested_archives();
129 // Select members from the archive as needed and add them to the
132 add_symbols(Symbol_table*, Layout*, Input_objects*, Mapfile*);
134 // Return the number of members in the archive.
136 count_members() const;
139 Archive(const Archive&);
140 Archive& operator=(const Archive&);
142 struct Archive_header;
144 // Get a view into the underlying file.
146 get_view(off_t start, section_size_type size, bool aligned, bool cache)
147 { return this->input_file_->file().get_view(0, start, size, aligned, cache); }
149 // Read the archive symbol map.
151 read_armap(off_t start, section_size_type size);
153 // Read an archive member header at OFF. CACHE is whether to cache
154 // the file view. Return the size of the member, and set *PNAME to
157 read_header(off_t off, bool cache, std::string* pname, off_t* nested_off);
159 // Interpret an archive header HDR at OFF. Return the size of the
160 // member, and set *PNAME to the name.
162 interpret_header(const Archive_header* hdr, off_t off, std::string* pname,
163 off_t* nested_off) const;
165 // Include all the archive members in the link.
167 include_all_members(Symbol_table*, Layout*, Input_objects*, Mapfile*);
169 // Include an archive member in the link.
171 include_member(Symbol_table*, Layout*, Input_objects*, off_t off,
172 Mapfile*, Symbol*, const char* why);
174 // Iterate over archive members.
175 class const_iterator;
183 friend class const_iterator;
185 // An entry in the archive map of symbols to object files.
188 // The offset to the symbol name in armap_names_.
190 // The file offset to the object in the archive.
194 // A simple hash code for off_t values.
198 size_t operator()(off_t val) const
199 { return static_cast<size_t>(val); }
202 // For keeping track of open nested archives in a thin archive file.
203 typedef Unordered_map<std::string, Archive*> Nested_archive_table;
205 // Name of object as printed to user.
207 // For reading the file.
208 Input_file* input_file_;
210 std::vector<Armap_entry> armap_;
211 // The names in the archive map.
212 std::string armap_names_;
213 // The extended name table.
214 std::string extended_names_;
215 // Track which symbols in the archive map are for elements which are
216 // defined or which have already been included in the link.
217 std::vector<bool> armap_checked_;
218 // Track which elements have been included by offset.
219 Unordered_set<off_t, Seen_hash> seen_offsets_;
220 // True if this is a thin archive.
221 const bool is_thin_archive_;
222 // Table of nested archives, indexed by filename.
223 Nested_archive_table nested_archives_;
224 // The directory search path.
226 // The task reading this archive.
230 // This class is used to read an archive and pick out the desired
231 // elements and add them to the link.
233 class Add_archive_symbols : public Task
236 Add_archive_symbols(Symbol_table* symtab, Layout* layout,
237 Input_objects* input_objects, Mapfile* mapfile,
238 Archive* archive, Input_group* input_group,
239 Task_token* this_blocker,
240 Task_token* next_blocker)
241 : symtab_(symtab), layout_(layout), input_objects_(input_objects),
242 mapfile_(mapfile), archive_(archive), input_group_(input_group),
243 this_blocker_(this_blocker), next_blocker_(next_blocker)
246 ~Add_archive_symbols();
248 // The standard Task methods.
262 if (this->archive_ == NULL)
263 return "Add_archive_symbols";
264 return "Add_archive_symbols " + this->archive_->file().filename();
268 Symbol_table* symtab_;
270 Input_objects* input_objects_;
273 Input_group* input_group_;
274 Task_token* this_blocker_;
275 Task_token* next_blocker_;
278 } // End namespace gold.
280 #endif // !defined(GOLD_ARCHIVE_H)