| // readsyms.cc -- read input file symbols for gold |
| |
| // Copyright 2006, 2007, 2008 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. |
| |
| #include "gold.h" |
| |
| #include <cstring> |
| |
| #include "elfcpp.h" |
| #include "options.h" |
| #include "dirsearch.h" |
| #include "symtab.h" |
| #include "object.h" |
| #include "archive.h" |
| #include "script.h" |
| #include "readsyms.h" |
| |
| namespace gold |
| { |
| |
| // If we fail to open the object, then we won't create an Add_symbols |
| // task. However, we still need to unblock the token, or else the |
| // link won't proceed to generate more error messages. We can only |
| // unblock tokens when the workqueue lock is held, so we need a dummy |
| // task to do that. The dummy task has to maintain the right sequence |
| // of blocks, so we need both this_blocker and next_blocker. |
| |
| class Unblock_token : public Task |
| { |
| public: |
| Unblock_token(Task_token* this_blocker, Task_token* next_blocker) |
| : this_blocker_(this_blocker), next_blocker_(next_blocker) |
| { } |
| |
| ~Unblock_token() |
| { |
| if (this->this_blocker_ != NULL) |
| delete this->this_blocker_; |
| } |
| |
| Task_token* |
| is_runnable() |
| { |
| if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked()) |
| return this->this_blocker_; |
| return NULL; |
| } |
| |
| void |
| locks(Task_locker* tl) |
| { tl->add(this, this->next_blocker_); } |
| |
| void |
| run(Workqueue*) |
| { } |
| |
| std::string |
| get_name() const |
| { return "Unblock_token"; } |
| |
| private: |
| Task_token* this_blocker_; |
| Task_token* next_blocker_; |
| }; |
| |
| // Class read_symbols. |
| |
| Read_symbols::~Read_symbols() |
| { |
| // The this_blocker_ and next_blocker_ pointers are passed on to the |
| // Add_symbols task. |
| } |
| |
| // Return whether a Read_symbols task is runnable. We can read an |
| // ordinary input file immediately. For an archive specified using |
| // -l, we have to wait until the search path is complete. |
| |
| Task_token* |
| Read_symbols::is_runnable() |
| { |
| if (this->input_argument_->is_file() |
| && this->input_argument_->file().may_need_search() |
| && this->dirpath_->token()->is_blocked()) |
| return this->dirpath_->token(); |
| |
| return NULL; |
| } |
| |
| // Return a Task_locker for a Read_symbols task. We don't need any |
| // locks here. |
| |
| void |
| Read_symbols::locks(Task_locker*) |
| { |
| } |
| |
| // Run a Read_symbols task. |
| |
| void |
| Read_symbols::run(Workqueue* workqueue) |
| { |
| // If we didn't queue a new task, then we need to explicitly unblock |
| // the token. |
| if (!this->do_read_symbols(workqueue)) |
| workqueue->queue_soon(new Unblock_token(this->this_blocker_, |
| this->next_blocker_)); |
| } |
| |
| // Open the file and read the symbols. Return true if a new task was |
| // queued, false if that could not happen due to some error. |
| |
| bool |
| Read_symbols::do_read_symbols(Workqueue* workqueue) |
| { |
| if (this->input_argument_->is_group()) |
| { |
| gold_assert(this->input_group_ == NULL); |
| this->do_group(workqueue); |
| return true; |
| } |
| |
| Input_file* input_file = new Input_file(&this->input_argument_->file()); |
| if (!input_file->open(this->options_, *this->dirpath_, this)) |
| return false; |
| |
| // Read enough of the file to pick up the entire ELF header. |
| |
| off_t filesize = input_file->file().filesize(); |
| |
| if (filesize == 0) |
| { |
| gold_error(_("%s: file is empty"), |
| input_file->file().filename().c_str()); |
| return false; |
| } |
| |
| int read_size = elfcpp::Elf_sizes<64>::ehdr_size; |
| if (filesize < read_size) |
| read_size = filesize; |
| |
| const unsigned char* ehdr = input_file->file().get_view(0, 0, read_size, |
| true, false); |
| |
| if (read_size >= 4) |
| { |
| static unsigned char elfmagic[4] = |
| { |
| elfcpp::ELFMAG0, elfcpp::ELFMAG1, |
| elfcpp::ELFMAG2, elfcpp::ELFMAG3 |
| }; |
| if (memcmp(ehdr, elfmagic, 4) == 0) |
| { |
| // This is an ELF object. |
| |
| Object* obj = make_elf_object(input_file->filename(), |
| input_file, 0, ehdr, read_size); |
| if (obj == NULL) |
| return false; |
| |
| Read_symbols_data* sd = new Read_symbols_data; |
| obj->read_symbols(sd); |
| |
| // Opening the file locked it, so now we need to unlock it. |
| // We need to unlock it before queuing the Add_symbols task, |
| // because the workqueue doesn't know about our lock on the |
| // file. If we queue the Add_symbols task first, it will be |
| // stuck on the end of the file lock, but since the |
| // workqueue doesn't know about that lock, it will never |
| // release the Add_symbols task. |
| |
| input_file->file().unlock(this); |
| |
| // We use queue_next because everything is cached for this |
| // task to run right away if possible. |
| |
| workqueue->queue_next(new Add_symbols(this->input_objects_, |
| this->symtab_, this->layout_, |
| obj, sd, |
| this->this_blocker_, |
| this->next_blocker_)); |
| |
| return true; |
| } |
| } |
| |
| if (read_size >= Archive::sarmag) |
| { |
| bool is_thin_archive |
| = memcmp(ehdr, Archive::armagt, Archive::sarmag) == 0; |
| if (is_thin_archive |
| || memcmp(ehdr, Archive::armag, Archive::sarmag) == 0) |
| { |
| // This is an archive. |
| Archive* arch = new Archive(this->input_argument_->file().name(), |
| input_file, is_thin_archive, |
| this->dirpath_, this); |
| arch->setup(this->input_objects_); |
| |
| // Unlock the archive so it can be used in the next task. |
| arch->unlock(this); |
| |
| workqueue->queue_next(new Add_archive_symbols(this->symtab_, |
| this->layout_, |
| this->input_objects_, |
| this->mapfile_, |
| arch, |
| this->input_group_, |
| this->this_blocker_, |
| this->next_blocker_)); |
| return true; |
| } |
| } |
| |
| // Queue up a task to try to parse this file as a script. We use a |
| // separate task so that the script will be read in order with other |
| // objects named on the command line. Also so that we don't try to |
| // read multiple scripts simultaneously, which could lead to |
| // unpredictable changes to the General_options structure. |
| |
| workqueue->queue_soon(new Read_script(this->options_, |
| this->symtab_, |
| this->layout_, |
| this->dirpath_, |
| this->input_objects_, |
| this->mapfile_, |
| this->input_group_, |
| this->input_argument_, |
| input_file, |
| this->this_blocker_, |
| this->next_blocker_)); |
| return true; |
| } |
| |
| // Handle a group. We need to walk through the arguments over and |
| // over until we don't see any new undefined symbols. We do this by |
| // setting off Read_symbols Tasks as usual, but recording the archive |
| // entries instead of deleting them. We also start a Finish_group |
| // Task which runs after we've read all the symbols. In that task we |
| // process the archives in a loop until we are done. |
| |
| void |
| Read_symbols::do_group(Workqueue* workqueue) |
| { |
| Input_group* input_group = new Input_group(); |
| |
| const Input_file_group* group = this->input_argument_->group(); |
| Task_token* this_blocker = this->this_blocker_; |
| |
| for (Input_file_group::const_iterator p = group->begin(); |
| p != group->end(); |
| ++p) |
| { |
| const Input_argument* arg = &*p; |
| gold_assert(arg->is_file()); |
| |
| Task_token* next_blocker = new Task_token(true); |
| next_blocker->add_blocker(); |
| workqueue->queue_soon(new Read_symbols(this->options_, |
| this->input_objects_, |
| this->symtab_, this->layout_, |
| this->dirpath_, this->mapfile_, |
| arg, input_group, |
| this_blocker, next_blocker)); |
| this_blocker = next_blocker; |
| } |
| |
| const int saw_undefined = this->symtab_->saw_undefined(); |
| workqueue->queue_soon(new Finish_group(this->input_objects_, |
| this->symtab_, |
| this->layout_, |
| this->mapfile_, |
| input_group, |
| saw_undefined, |
| this_blocker, |
| this->next_blocker_)); |
| } |
| |
| // Return a debugging name for a Read_symbols task. |
| |
| std::string |
| Read_symbols::get_name() const |
| { |
| if (!this->input_argument_->is_group()) |
| { |
| std::string ret("Read_symbols "); |
| if (this->input_argument_->file().is_lib()) |
| ret += "-l"; |
| ret += this->input_argument_->file().name(); |
| return ret; |
| } |
| |
| std::string ret("Read_symbols group ("); |
| bool add_space = false; |
| const Input_file_group* group = this->input_argument_->group(); |
| for (Input_file_group::const_iterator p = group->begin(); |
| p != group->end(); |
| ++p) |
| { |
| if (add_space) |
| ret += ' '; |
| ret += p->file().name(); |
| add_space = true; |
| } |
| return ret + ')'; |
| } |
| |
| // Class Add_symbols. |
| |
| Add_symbols::~Add_symbols() |
| { |
| if (this->this_blocker_ != NULL) |
| delete this->this_blocker_; |
| // next_blocker_ is deleted by the task associated with the next |
| // input file. |
| } |
| |
| // We are blocked by this_blocker_. We block next_blocker_. We also |
| // lock the file. |
| |
| Task_token* |
| Add_symbols::is_runnable() |
| { |
| if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked()) |
| return this->this_blocker_; |
| if (this->object_->is_locked()) |
| return this->object_->token(); |
| return NULL; |
| } |
| |
| void |
| Add_symbols::locks(Task_locker* tl) |
| { |
| tl->add(this, this->next_blocker_); |
| tl->add(this, this->object_->token()); |
| } |
| |
| // Add the symbols in the object to the symbol table. |
| |
| void |
| Add_symbols::run(Workqueue*) |
| { |
| if (!this->input_objects_->add_object(this->object_)) |
| { |
| // FIXME: We need to close the descriptor here. |
| delete this->object_; |
| } |
| else |
| { |
| this->object_->layout(this->symtab_, this->layout_, this->sd_); |
| this->object_->add_symbols(this->symtab_, this->sd_); |
| this->object_->release(); |
| } |
| delete this->sd_; |
| this->sd_ = NULL; |
| } |
| |
| // Class Finish_group. |
| |
| Finish_group::~Finish_group() |
| { |
| if (this->this_blocker_ != NULL) |
| delete this->this_blocker_; |
| // next_blocker_ is deleted by the task associated with the next |
| // input file following the group. |
| } |
| |
| // We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_. |
| |
| Task_token* |
| Finish_group::is_runnable() |
| { |
| if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked()) |
| return this->this_blocker_; |
| return NULL; |
| } |
| |
| void |
| Finish_group::locks(Task_locker* tl) |
| { |
| tl->add(this, this->next_blocker_); |
| } |
| |
| // Loop over the archives until there are no new undefined symbols. |
| |
| void |
| Finish_group::run(Workqueue*) |
| { |
| int saw_undefined = this->saw_undefined_; |
| while (saw_undefined != this->symtab_->saw_undefined()) |
| { |
| saw_undefined = this->symtab_->saw_undefined(); |
| |
| for (Input_group::const_iterator p = this->input_group_->begin(); |
| p != this->input_group_->end(); |
| ++p) |
| { |
| Task_lock_obj<Archive> tl(this, *p); |
| |
| (*p)->add_symbols(this->symtab_, this->layout_, |
| this->input_objects_, this->mapfile_); |
| } |
| } |
| |
| // Delete all the archives now that we no longer need them. |
| for (Input_group::const_iterator p = this->input_group_->begin(); |
| p != this->input_group_->end(); |
| ++p) |
| delete *p; |
| delete this->input_group_; |
| } |
| |
| // Class Read_script |
| |
| Read_script::~Read_script() |
| { |
| if (this->this_blocker_ != NULL) |
| delete this->this_blocker_; |
| // next_blocker_ is deleted by the task associated with the next |
| // input file. |
| } |
| |
| // We are blocked by this_blocker_. |
| |
| Task_token* |
| Read_script::is_runnable() |
| { |
| if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked()) |
| return this->this_blocker_; |
| return NULL; |
| } |
| |
| // We don't unlock next_blocker_ here. If the script names any input |
| // files, then the last file will be responsible for unlocking it. |
| |
| void |
| Read_script::locks(Task_locker*) |
| { |
| } |
| |
| // Read the script, if it is a script. |
| |
| void |
| Read_script::run(Workqueue* workqueue) |
| { |
| bool used_next_blocker; |
| if (!read_input_script(workqueue, this->options_, this->symtab_, |
| this->layout_, this->dirpath_, this->input_objects_, |
| this->mapfile_, this->input_group_, |
| this->input_argument_, this->input_file_, |
| this->next_blocker_, &used_next_blocker)) |
| { |
| // Here we have to handle any other input file types we need. |
| gold_error(_("%s: not an object or archive"), |
| this->input_file_->file().filename().c_str()); |
| } |
| |
| if (!used_next_blocker) |
| { |
| // Queue up a task to unlock next_blocker. We can't just unlock |
| // it here, as we don't hold the workqueue lock. |
| workqueue->queue_soon(new Unblock_token(NULL, this->next_blocker_)); |
| } |
| } |
| |
| // Return a debugging name for a Read_script task. |
| |
| std::string |
| Read_script::get_name() const |
| { |
| std::string ret("Read_script "); |
| if (this->input_argument_->file().is_lib()) |
| ret += "-l"; |
| ret += this->input_argument_->file().name(); |
| return ret; |
| } |
| |
| } // End namespace gold. |