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Diffstat (limited to 'binutils-2.25/gold/archive.h')
| -rw-r--r-- | binutils-2.25/gold/archive.h | 571 |
1 files changed, 571 insertions, 0 deletions
diff --git a/binutils-2.25/gold/archive.h b/binutils-2.25/gold/archive.h new file mode 100644 index 00000000..3d75de62 --- /dev/null +++ b/binutils-2.25/gold/archive.h @@ -0,0 +1,571 @@ +// 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 : public Library_base +{ + public: + 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. 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(); + + // Get a reference to the underlying file. + File_read& + file() + { return this->input_file_->file(); } + + const File_read& + file() const + { return this->input_file_->file(); } + + // Lock the underlying file. + void + lock(const Task* t) + { this->input_file_->file().lock(t); } + + // Unlock the underlying file. + void + 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. + 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; + + // 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, 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); + + // Interpret an archive header HDR at OFF. Return the size of the + // member, and set *PNAME to the name. + off_t + 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 + 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 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 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 +// elements and add them to the link. + +class Add_archive_symbols : public Task +{ + public: + Add_archive_symbols(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) + : symtab_(symtab), layout_(layout), input_objects_(input_objects), + 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. + + Task_token* + is_runnable(); + + void + locks(Task_locker*); + + void + run(Workqueue*); + + 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) |