// archive.h -- archive support for gold -*- C++ -*-
+// Copyright 2006, 2007, 2008, 2010, 2011, 2013 Free Software Foundation, Inc.
+// Written by Ian Lance Taylor <iant@google.com>.
+
+// This file is part of gold.
+
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+// MA 02110-1301, USA.
+
#ifndef GOLD_ARCHIVE_H
#define GOLD_ARCHIVE_H
#include <string>
#include <vector>
+#include "fileread.h"
#include "workqueue.h"
namespace gold
{
+class Task;
+class Input_argument;
class Input_file;
class Input_objects;
class Input_group;
class Layout;
class Symbol_table;
+class Object;
+struct Read_symbols_data;
+class Input_file_lib;
+class Incremental_archive_entry;
+
+// An entry in the archive map of offsets to members.
+struct Archive_member
+{
+ Archive_member()
+ : obj_(NULL), sd_(NULL), arg_serial_(0)
+ { }
+ Archive_member(Object* obj, Read_symbols_data* sd)
+ : obj_(obj), sd_(sd), arg_serial_(0)
+ { }
+ // The object file.
+ Object* obj_;
+ // The data to pass from read_symbols() to add_symbols().
+ Read_symbols_data* sd_;
+ // The serial number of the file in the argument list.
+ unsigned int arg_serial_;
+};
+
+// This class serves as a base class for Archive and Lib_group objects.
+
+class Library_base
+{
+ public:
+ Library_base(Task* task)
+ : task_(task), incremental_info_(NULL)
+ { }
+
+ virtual
+ ~Library_base()
+ { }
+
+ // The file name.
+ const std::string&
+ filename() const
+ { return this->do_filename(); }
+
+ // The modification time of the archive file.
+ Timespec
+ get_mtime()
+ { return this->do_get_mtime(); }
+
+ // When we see a symbol in an archive we might decide to include the member,
+ // not include the member or be undecided. This enum represents these
+ // possibilities.
+
+ enum Should_include
+ {
+ SHOULD_INCLUDE_NO,
+ SHOULD_INCLUDE_YES,
+ SHOULD_INCLUDE_UNKNOWN
+ };
+
+ static Should_include
+ should_include_member(Symbol_table* symtab, Layout*, const char* sym_name,
+ Symbol** symp, std::string* why, char** tmpbufp,
+ size_t* tmpbuflen);
+
+ // Store a pointer to the incremental link info for the library.
+ void
+ set_incremental_info(Incremental_archive_entry* info)
+ { this->incremental_info_ = info; }
+
+ // Return the pointer to the incremental link info for the library.
+ Incremental_archive_entry*
+ incremental_info() const
+ { return this->incremental_info_; }
+
+ // Abstract base class for processing unused symbols.
+ class Symbol_visitor_base
+ {
+ public:
+ Symbol_visitor_base()
+ { }
+
+ virtual
+ ~Symbol_visitor_base()
+ { }
+
+ // This function will be called for each unused global
+ // symbol in a library, with a pointer to the symbol name.
+ virtual void
+ visit(const char* /* name */) = 0;
+ };
+
+ // Iterator for unused global symbols in the library.
+ // Calls v->visit() for each global symbol defined
+ // in each unused library member, passing a pointer to
+ // the symbol name.
+ void
+ for_all_unused_symbols(Symbol_visitor_base* v) const
+ { this->do_for_all_unused_symbols(v); }
+
+ protected:
+ // The task reading this archive.
+ Task *task_;
+
+ private:
+ // The file name.
+ virtual const std::string&
+ do_filename() const = 0;
+
+ // Return the modification time of the archive file.
+ virtual Timespec
+ do_get_mtime() = 0;
+
+ // Iterator for unused global symbols in the library.
+ virtual void
+ do_for_all_unused_symbols(Symbol_visitor_base* v) const = 0;
+
+ // The incremental link information for this archive.
+ Incremental_archive_entry* incremental_info_;
+};
// This class represents an archive--generally a libNAME.a file.
// Archives have a symbol table and a list of objects.
-class Archive
+class Archive : public Library_base
{
public:
- Archive(const std::string& name, Input_file* input_file)
- : name_(name), input_file_(input_file), armap_(), extended_names_()
- { }
+ Archive(const std::string& name, Input_file* input_file,
+ bool is_thin_archive, Dirsearch* dirpath, Task* task);
// The length of the magic string at the start of an archive.
static const int sarmag = 8;
// The magic string at the start of an archive.
static const char armag[sarmag];
+ static const char armagt[sarmag];
// The string expected at the end of an archive member header.
static const char arfmag[2];
- // The name of the object.
+ // The name of the object. This is the name used on the command
+ // line; e.g., if "-lgcc" is on the command line, this will be
+ // "gcc".
const std::string&
name() const
{ return this->name_; }
+ // The input file.
+ const Input_file*
+ input_file() const
+ { return this->input_file_; }
+
// Set up the archive: read the symbol map.
void
setup();
file()
{ return this->input_file_->file(); }
+ const File_read&
+ file() const
+ { return this->input_file_->file(); }
+
// Lock the underlying file.
void
- lock()
- { this->input_file_->file().lock(); }
+ lock(const Task* t)
+ { this->input_file_->file().lock(t); }
// Unlock the underlying file.
void
- unlock()
- { this->input_file_->file().unlock(); }
+ unlock(const Task* t)
+ { this->input_file_->file().unlock(t); }
// Return whether the underlying file is locked.
bool
is_locked() const
{ return this->input_file_->file().is_locked(); }
+ // Return the token, so that the task can be queued.
+ Task_token*
+ token()
+ { return this->input_file_->file().token(); }
+
+ // Release the underlying file.
+ void
+ release()
+ { this->input_file_->file().release(); }
+
+ // Clear uncached views in the underlying file.
+ void
+ clear_uncached_views()
+ { this->input_file_->file().clear_uncached_views(); }
+
+ // Whether this is a thin archive.
+ bool
+ is_thin_archive() const
+ { return this->is_thin_archive_; }
+
+ // Unlock any nested archives.
+ void
+ unlock_nested_archives();
+
// Select members from the archive as needed and add them to the
// link.
- void
- add_symbols(Symbol_table*, Layout*, Input_objects*);
+ bool
+ add_symbols(Symbol_table*, Layout*, Input_objects*, Mapfile*);
+
+ // Return whether the archive defines the symbol.
+ bool
+ defines_symbol(Symbol*) const;
+
+ // Dump statistical information to stderr.
+ static void
+ print_stats();
+
+ // Return the number of members in the archive.
+ size_t
+ count_members();
+
+ // Return the no-export flag.
+ bool
+ no_export()
+ { return this->no_export_; }
private:
Archive(const Archive&);
Archive& operator=(const Archive&);
+ // The file name.
+ const std::string&
+ do_filename() const
+ { return this->input_file_->filename(); }
+
+ // The modification time of the archive file.
+ Timespec
+ do_get_mtime()
+ { return this->file().get_mtime(); }
+
struct Archive_header;
- class Add_archive_symbols_locker;
+
+ // Total number of archives seen.
+ static unsigned int total_archives;
+ // Total number of archive members seen.
+ static unsigned int total_members;
+ // Number of archive members loaded.
+ static unsigned int total_members_loaded;
// Get a view into the underlying file.
const unsigned char*
- get_view(off_t start, off_t size)
- { return this->input_file_->file().get_view(start, size); }
+ get_view(off_t start, section_size_type size, bool aligned, bool cache)
+ { return this->input_file_->file().get_view(0, start, size, aligned, cache); }
+
+ // Read the archive symbol map.
+ void
+ read_armap(off_t start, section_size_type size);
+
+ // Read an archive member header at OFF. CACHE is whether to cache
+ // the file view. Return the size of the member, and set *PNAME to
+ // the name.
+ off_t
+ read_header(off_t off, bool cache, std::string* pname, off_t* nested_off);
- // Read an archive member header at OFF. Return the size of the
+ // Interpret an archive header HDR at OFF. Return the size of the
// member, and set *PNAME to the name.
off_t
- read_header(off_t off, std::string* pname);
+ interpret_header(const Archive_header* hdr, off_t off, std::string* pname,
+ off_t* nested_off) const;
+
+ // Get the file and offset for an archive member, which may be an
+ // external member of a thin archive. Set *INPUT_FILE to the
+ // file containing the actual member, *MEMOFF to the offset
+ // within that file (0 if not a nested archive), and *MEMBER_NAME
+ // to the name of the archive member. Return TRUE on success.
+ bool
+ get_file_and_offset(off_t off, Input_file** input_file, off_t* memoff,
+ off_t* memsize, std::string* member_name);
+
+ // Return an ELF object for the member at offset OFF.
+ Object*
+ get_elf_object_for_member(off_t off, bool*);
+
+ // Read the symbols from all the archive members in the link.
+ void
+ read_all_symbols();
+
+ // Read the symbols from an archive member in the link. OFF is the file
+ // offset of the member header.
+ void
+ read_symbols(off_t off);
+
+ // Include all the archive members in the link.
+ bool
+ include_all_members(Symbol_table*, Layout*, Input_objects*, Mapfile*);
// Include an archive member in the link.
+ bool
+ include_member(Symbol_table*, Layout*, Input_objects*, off_t off,
+ Mapfile*, Symbol*, const char* why);
+
+ // Return whether we found this archive by searching a directory.
+ bool
+ searched_for() const
+ { return this->input_file_->will_search_for(); }
+
+ // Iterate over archive members.
+ class const_iterator;
+
+ const_iterator
+ begin();
+
+ const_iterator
+ end();
+
+ friend class const_iterator;
+
+ // Iterator for unused global symbols in the library.
void
- include_member(Symbol_table*, Layout*, Input_objects*, off_t off);
+ do_for_all_unused_symbols(Symbol_visitor_base* v) const;
// An entry in the archive map of symbols to object files.
struct Armap_entry
{
- // The symbol name.
- const char* name;
- // The offset to the file.
- off_t offset;
+ // The offset to the symbol name in armap_names_.
+ off_t name_offset;
+ // The file offset to the object in the archive.
+ off_t file_offset;
+ };
+
+ // A simple hash code for off_t values.
+ class Seen_hash
+ {
+ public:
+ size_t operator()(off_t val) const
+ { return static_cast<size_t>(val); }
};
+ // For keeping track of open nested archives in a thin archive file.
+ typedef Unordered_map<std::string, Archive*> Nested_archive_table;
+
// Name of object as printed to user.
std::string name_;
// For reading the file.
Input_file* input_file_;
// The archive map.
std::vector<Armap_entry> armap_;
+ // The names in the archive map.
+ std::string armap_names_;
// The extended name table.
std::string extended_names_;
- // Track which symbols in the archive map are for elements which
- // have already been included in the link.
- std::vector<bool> seen_;
+ // Track which symbols in the archive map are for elements which are
+ // defined or which have already been included in the link.
+ std::vector<bool> armap_checked_;
+ // Track which elements have been included by offset.
+ Unordered_set<off_t, Seen_hash> seen_offsets_;
+ // Table of objects whose symbols have been pre-read.
+ std::map<off_t, Archive_member> members_;
+ // True if this is a thin archive.
+ const bool is_thin_archive_;
+ // True if we have included at least one object from this archive.
+ bool included_member_;
+ // Table of nested archives, indexed by filename.
+ Nested_archive_table nested_archives_;
+ // The directory search path.
+ Dirsearch* dirpath_;
+ // Number of members in this archive;
+ unsigned int num_members_;
+ // True if we exclude this library archive from automatic export.
+ bool no_export_;
+ // True if this library has been included as a --whole-archive.
+ bool included_all_members_;
};
// This class is used to read an archive and pick out the desired
{
public:
Add_archive_symbols(Symbol_table* symtab, Layout* layout,
- Input_objects* input_objects,
+ Input_objects* input_objects, Dirsearch* dirpath,
+ int dirindex, Mapfile* mapfile,
+ const Input_argument* input_argument,
Archive* archive, Input_group* input_group,
Task_token* this_blocker,
Task_token* next_blocker)
: symtab_(symtab), layout_(layout), input_objects_(input_objects),
- archive_(archive), input_group_(input_group),
- this_blocker_(this_blocker), next_blocker_(next_blocker)
+ dirpath_(dirpath), dirindex_(dirindex), mapfile_(mapfile),
+ input_argument_(input_argument), archive_(archive),
+ input_group_(input_group), this_blocker_(this_blocker),
+ next_blocker_(next_blocker)
{ }
~Add_archive_symbols();
// The standard Task methods.
- Is_runnable_type
- is_runnable(Workqueue*);
+ Task_token*
+ is_runnable();
- Task_locker*
- locks(Workqueue*);
+ void
+ locks(Task_locker*);
void
run(Workqueue*);
- private:
- class Add_archive_symbols_locker;
+ std::string
+ get_name() const
+ {
+ if (this->archive_ == NULL)
+ return "Add_archive_symbols";
+ return "Add_archive_symbols " + this->archive_->file().filename();
+ }
+ private:
Symbol_table* symtab_;
Layout* layout_;
Input_objects* input_objects_;
+ Dirsearch* dirpath_;
+ int dirindex_;
+ Mapfile* mapfile_;
+ const Input_argument* input_argument_;
Archive* archive_;
Input_group* input_group_;
Task_token* this_blocker_;
Task_token* next_blocker_;
};
+// This class represents the files surrounded by a --start-lib ... --end-lib.
+
+class Lib_group : public Library_base
+{
+ public:
+ Lib_group(const Input_file_lib* lib, Task* task);
+
+ // Select members from the lib group as needed and add them to the link.
+ void
+ add_symbols(Symbol_table*, Layout*, Input_objects*);
+
+ // Include a member of the lib group in the link.
+ void
+ include_member(Symbol_table*, Layout*, Input_objects*, const Archive_member&);
+
+ Archive_member*
+ get_member(int i)
+ {
+ return &this->members_[i];
+ }
+
+ // Total number of archives seen.
+ static unsigned int total_lib_groups;
+ // Total number of archive members seen.
+ static unsigned int total_members;
+ // Number of archive members loaded.
+ static unsigned int total_members_loaded;
+
+ // Dump statistical information to stderr.
+ static void
+ print_stats();
+
+ private:
+ // The file name.
+ const std::string&
+ do_filename() const;
+
+ // A Lib_group does not have a modification time, since there is no
+ // real library file.
+ Timespec
+ do_get_mtime()
+ { return Timespec(0, 0); }
+
+ // Iterator for unused global symbols in the library.
+ void
+ do_for_all_unused_symbols(Symbol_visitor_base*) const;
+
+ // Table of the objects in the group.
+ std::vector<Archive_member> members_;
+};
+
+// This class is used to pick out the desired elements and add them to the link.
+
+class Add_lib_group_symbols : public Task
+{
+ public:
+ Add_lib_group_symbols(Symbol_table* symtab, Layout* layout,
+ Input_objects* input_objects,
+ Lib_group* lib, Task_token* next_blocker)
+ : symtab_(symtab), layout_(layout), input_objects_(input_objects),
+ lib_(lib), readsyms_blocker_(NULL), this_blocker_(NULL),
+ next_blocker_(next_blocker)
+ { }
+
+ ~Add_lib_group_symbols();
+
+ // The standard Task methods.
+
+ Task_token*
+ is_runnable();
+
+ void
+ locks(Task_locker*);
+
+ void
+ run(Workqueue*);
+
+ // Set the blocker to use for this task.
+ void
+ set_blocker(Task_token* readsyms_blocker, Task_token* this_blocker)
+ {
+ gold_assert(this->readsyms_blocker_ == NULL && this->this_blocker_ == NULL);
+ this->readsyms_blocker_ = readsyms_blocker;
+ this->this_blocker_ = this_blocker;
+ }
+
+ std::string
+ get_name() const
+ {
+ return "Add_lib_group_symbols";
+ }
+
+ private:
+ Symbol_table* symtab_;
+ Layout* layout_;
+ Input_objects* input_objects_;
+ Lib_group* lib_;
+ Task_token* readsyms_blocker_;
+ Task_token* this_blocker_;
+ Task_token* next_blocker_;
+};
+
} // End namespace gold.
#endif // !defined(GOLD_ARCHIVE_H)