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// archive.h -- archive support for gold -*- C++ -*-
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// Copyright 2006, 2007, 2008, 2010, 2011 Free Software Foundation, Inc.
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// Written by Ian Lance Taylor <iant@google.com>.
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// This file is part of gold.
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// This program is free software; you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation; either version 3 of the License, or
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// (at your option) any later version.
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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// You should have received a copy of the GNU General Public License
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// along with this program; if not, write to the Free Software
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// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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// MA 02110-1301, USA.
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#ifndef GOLD_ARCHIVE_H
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#define GOLD_ARCHIVE_H
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#include "workqueue.h"
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class Read_symbols_data;
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class Incremental_archive_entry;
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// An entry in the archive map of offsets to members.
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: obj_(NULL), sd_(NULL), arg_serial_(0)
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Archive_member(Object* obj, Read_symbols_data* sd)
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: obj_(obj), sd_(sd), arg_serial_(0)
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// The data to pass from read_symbols() to add_symbols().
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Read_symbols_data* sd_;
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// The serial number of the file in the argument list.
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unsigned int arg_serial_;
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// This class serves as a base class for Archive and Lib_group objects.
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Library_base(Task* task)
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: task_(task), incremental_info_(NULL)
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{ return this->do_filename(); }
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// The modification time of the archive file.
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{ return this->do_get_mtime(); }
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// When we see a symbol in an archive we might decide to include the member,
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// not include the member or be undecided. This enum represents these
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SHOULD_INCLUDE_UNKNOWN
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should_include_member(Symbol_table* symtab, Layout*, const char* sym_name,
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Symbol** symp, std::string* why, char** tmpbufp,
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// Store a pointer to the incremental link info for the library.
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set_incremental_info(Incremental_archive_entry* info)
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{ this->incremental_info_ = info; }
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// Return the pointer to the incremental link info for the library.
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Incremental_archive_entry*
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incremental_info() const
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{ return this->incremental_info_; }
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// Abstract base class for processing unused symbols.
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class Symbol_visitor_base
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Symbol_visitor_base()
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~Symbol_visitor_base()
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// This function will be called for each unused global
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// symbol in a library, with a pointer to the symbol name.
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visit(const char* /* name */) = 0;
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// Iterator for unused global symbols in the library.
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// Calls v->visit() for each global symbol defined
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// in each unused library member, passing a pointer to
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for_all_unused_symbols(Symbol_visitor_base* v) const
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{ this->do_for_all_unused_symbols(v); }
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// The task reading this archive.
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virtual const std::string&
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do_filename() const = 0;
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// Return the modification time of the archive file.
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// Iterator for unused global symbols in the library.
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do_for_all_unused_symbols(Symbol_visitor_base* v) const = 0;
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// The incremental link information for this archive.
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Incremental_archive_entry* incremental_info_;
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// This class represents an archive--generally a libNAME.a file.
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// Archives have a symbol table and a list of objects.
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class Archive : public Library_base
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Archive(const std::string& name, Input_file* input_file,
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bool is_thin_archive, Dirsearch* dirpath, Task* task);
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// The length of the magic string at the start of an archive.
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static const int sarmag = 8;
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// The magic string at the start of an archive.
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static const char armag[sarmag];
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static const char armagt[sarmag];
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// The string expected at the end of an archive member header.
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static const char arfmag[2];
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// The name of the object. This is the name used on the command
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// line; e.g., if "-lgcc" is on the command line, this will be
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{ return this->name_; }
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{ return this->input_file_; }
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// Set up the archive: read the symbol map.
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// Get a reference to the underlying file.
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{ return this->input_file_->file(); }
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{ return this->input_file_->file(); }
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// Lock the underlying file.
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{ this->input_file_->file().lock(t); }
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// Unlock the underlying file.
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unlock(const Task* t)
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{ this->input_file_->file().unlock(t); }
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// Return whether the underlying file is locked.
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{ return this->input_file_->file().is_locked(); }
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// Return the token, so that the task can be queued.
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{ return this->input_file_->file().token(); }
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// Release the underlying file.
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{ this->input_file_->file().release(); }
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// Clear uncached views in the underlying file.
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clear_uncached_views()
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{ this->input_file_->file().clear_uncached_views(); }
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// Whether this is a thin archive.
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is_thin_archive() const
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{ return this->is_thin_archive_; }
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// Unlock any nested archives.
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unlock_nested_archives();
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// Select members from the archive as needed and add them to the
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add_symbols(Symbol_table*, Layout*, Input_objects*, Mapfile*);
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// Return whether the archive defines the symbol.
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defines_symbol(Symbol*) const;
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// Dump statistical information to stderr.
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// Return the number of members in the archive.
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// Return the no-export flag.
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{ return this->no_export_; }
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Archive(const Archive&);
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Archive& operator=(const Archive&);
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{ return this->input_file_->filename(); }
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// The modification time of the archive file.
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{ return this->file().get_mtime(); }
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struct Archive_header;
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// Total number of archives seen.
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static unsigned int total_archives;
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// Total number of archive members seen.
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static unsigned int total_members;
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// Number of archive members loaded.
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static unsigned int total_members_loaded;
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// Get a view into the underlying file.
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get_view(off_t start, section_size_type size, bool aligned, bool cache)
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{ return this->input_file_->file().get_view(0, start, size, aligned, cache); }
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// Read the archive symbol map.
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read_armap(off_t start, section_size_type size);
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// Read an archive member header at OFF. CACHE is whether to cache
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// the file view. Return the size of the member, and set *PNAME to
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read_header(off_t off, bool cache, std::string* pname, off_t* nested_off);
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// Interpret an archive header HDR at OFF. Return the size of the
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// member, and set *PNAME to the name.
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interpret_header(const Archive_header* hdr, off_t off, std::string* pname,
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off_t* nested_off) const;
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// Get the file and offset for an archive member, which may be an
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// external member of a thin archive. Set *INPUT_FILE to the
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// file containing the actual member, *MEMOFF to the offset
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// within that file (0 if not a nested archive), and *MEMBER_NAME
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// to the name of the archive member. Return TRUE on success.
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get_file_and_offset(off_t off, Input_file** input_file, off_t* memoff,
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off_t* memsize, std::string* member_name);
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// Return an ELF object for the member at offset OFF.
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get_elf_object_for_member(off_t off, bool*);
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// Read the symbols from all the archive members in the link.
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// Read the symbols from an archive member in the link. OFF is the file
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// offset of the member header.
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read_symbols(off_t off);
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// Include all the archive members in the link.
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include_all_members(Symbol_table*, Layout*, Input_objects*, Mapfile*);
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// Include an archive member in the link.
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include_member(Symbol_table*, Layout*, Input_objects*, off_t off,
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Mapfile*, Symbol*, const char* why);
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// Return whether we found this archive by searching a directory.
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{ return this->input_file_->will_search_for(); }
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// Iterate over archive members.
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class const_iterator;
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friend class const_iterator;
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// Iterator for unused global symbols in the library.
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do_for_all_unused_symbols(Symbol_visitor_base* v) const;
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// An entry in the archive map of symbols to object files.
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// The offset to the symbol name in armap_names_.
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// The file offset to the object in the archive.
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// A simple hash code for off_t values.
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size_t operator()(off_t val) const
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{ return static_cast<size_t>(val); }
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// For keeping track of open nested archives in a thin archive file.
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typedef Unordered_map<std::string, Archive*> Nested_archive_table;
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// Name of object as printed to user.
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// For reading the file.
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Input_file* input_file_;
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std::vector<Armap_entry> armap_;
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// The names in the archive map.
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std::string armap_names_;
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// The extended name table.
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std::string extended_names_;
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// Track which symbols in the archive map are for elements which are
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// defined or which have already been included in the link.
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std::vector<bool> armap_checked_;
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// Track which elements have been included by offset.
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Unordered_set<off_t, Seen_hash> seen_offsets_;
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// Table of objects whose symbols have been pre-read.
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std::map<off_t, Archive_member> members_;
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// True if this is a thin archive.
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const bool is_thin_archive_;
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// True if we have included at least one object from this archive.
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bool included_member_;
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// Table of nested archives, indexed by filename.
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Nested_archive_table nested_archives_;
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// The directory search path.
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// Number of members in this archive;
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unsigned int num_members_;
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// True if we exclude this library archive from automatic export.
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// True if this library has been included as a --whole-archive.
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bool included_all_members_;
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// This class is used to read an archive and pick out the desired
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// elements and add them to the link.
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class Add_archive_symbols : public Task
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Add_archive_symbols(Symbol_table* symtab, Layout* layout,
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Input_objects* input_objects, Dirsearch* dirpath,
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int dirindex, Mapfile* mapfile,
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const Input_argument* input_argument,
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Archive* archive, Input_group* input_group,
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Task_token* this_blocker,
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Task_token* next_blocker)
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: symtab_(symtab), layout_(layout), input_objects_(input_objects),
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dirpath_(dirpath), dirindex_(dirindex), mapfile_(mapfile),
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input_argument_(input_argument), archive_(archive),
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input_group_(input_group), this_blocker_(this_blocker),
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next_blocker_(next_blocker)
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~Add_archive_symbols();
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// The standard Task methods.
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if (this->archive_ == NULL)
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return "Add_archive_symbols";
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return "Add_archive_symbols " + this->archive_->file().filename();
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Symbol_table* symtab_;
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Input_objects* input_objects_;
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const Input_argument* input_argument_;
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Input_group* input_group_;
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Task_token* this_blocker_;
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Task_token* next_blocker_;
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// This class represents the files surrounded by a --start-lib ... --end-lib.
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class Lib_group : public Library_base
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Lib_group(const Input_file_lib* lib, Task* task);
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// Select members from the lib group as needed and add them to the link.
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add_symbols(Symbol_table*, Layout*, Input_objects*);
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// Include a member of the lib group in the link.
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include_member(Symbol_table*, Layout*, Input_objects*, const Archive_member&);
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return &this->members_[i];
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// Total number of archives seen.
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static unsigned int total_lib_groups;
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// Total number of archive members seen.
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static unsigned int total_members;
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// Number of archive members loaded.
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static unsigned int total_members_loaded;
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// Dump statistical information to stderr.
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// A Lib_group does not have a modification time, since there is no
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// real library file.
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{ return Timespec(0, 0); }
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// Iterator for unused global symbols in the library.
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do_for_all_unused_symbols(Symbol_visitor_base*) const;
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// For reading the files.
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const Input_file_lib* lib_;
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// Table of the objects in the group.
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std::vector<Archive_member> members_;
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// This class is used to pick out the desired elements and add them to the link.
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class Add_lib_group_symbols : public Task
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Add_lib_group_symbols(Symbol_table* symtab, Layout* layout,
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Input_objects* input_objects,
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Lib_group* lib, Task_token* next_blocker)
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: symtab_(symtab), layout_(layout), input_objects_(input_objects),
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lib_(lib), readsyms_blocker_(NULL), this_blocker_(NULL),
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next_blocker_(next_blocker)
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~Add_lib_group_symbols();
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// The standard Task methods.
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// Set the blocker to use for this task.
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set_blocker(Task_token* readsyms_blocker, Task_token* this_blocker)
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gold_assert(this->readsyms_blocker_ == NULL && this->this_blocker_ == NULL);
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this->readsyms_blocker_ = readsyms_blocker;
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this->this_blocker_ = this_blocker;
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return "Add_lib_group_symbols";
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Symbol_table* symtab_;
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Input_objects* input_objects_;
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Task_token* readsyms_blocker_;
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Task_token* this_blocker_;
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Task_token* next_blocker_;
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} // End namespace gold.
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#endif // !defined(GOLD_ARCHIVE_H)