// target-select.cc -- select a target for an object file // Copyright 2006, 2007, 2008, 2009, 2010, 2011 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 <cstdio> #include <cstring> #include "elfcpp.h" #include "options.h" #include "parameters.h" #include "target-select.h" namespace { // The start of the list of target selectors. gold::Target_selector* target_selectors; } // End anonymous namespace. namespace gold { // Class Set_target_once. void Set_target_once::do_run_once(void*) { this->target_selector_->set_target(); } // Construct a Target_selector, which means adding it to the linked // list. This runs at global constructor time, so we want it to be // fast. Target_selector::Target_selector(int machine, int size, bool is_big_endian, const char* bfd_name, const char* emulation) : machine_(machine), size_(size), is_big_endian_(is_big_endian), bfd_name_(bfd_name), emulation_(emulation), instantiated_target_(NULL), set_target_once_(this) { this->next_ = target_selectors; target_selectors = this; } // Instantiate the target and return it. Use SET_TARGET_ONCE_ to // avoid instantiating two instances of the same target. Target* Target_selector::instantiate_target() { this->set_target_once_.run_once(NULL); return this->instantiated_target_; } // Instantiate the target. This is called at most once. void Target_selector::set_target() { gold_assert(this->instantiated_target_ == NULL); this->instantiated_target_ = this->do_instantiate_target(); } // If we instantiated TARGET, return the corresponding BFD name. const char* Target_selector::do_target_bfd_name(const Target* target) { if (!this->is_our_target(target)) return NULL; const char* my_bfd_name = this->bfd_name(); gold_assert(my_bfd_name != NULL); return my_bfd_name; } // Find the target for an ELF file. Target* select_target(int machine, int size, bool is_big_endian, int osabi, int abiversion) { for (Target_selector* p = target_selectors; p != NULL; p = p->next()) { int pmach = p->machine(); if ((pmach == machine || pmach == elfcpp::EM_NONE) && p->get_size() == size && (p->is_big_endian() ? is_big_endian : !is_big_endian)) { Target* ret = p->recognize(machine, osabi, abiversion); if (ret != NULL) return ret; } } return NULL; } // Find a target using a BFD name. This is used to support the // --oformat option. Target* select_target_by_bfd_name(const char* name) { for (Target_selector* p = target_selectors; p != NULL; p = p->next()) { const char* pname = p->bfd_name(); if (pname == NULL || strcmp(pname, name) == 0) { Target* ret = p->recognize_by_bfd_name(name); if (ret != NULL) return ret; } } return NULL; } // Find a target using a GNU linker emulation. This is used to // support the -m option. Target* select_target_by_emulation(const char* name) { for (Target_selector* p = target_selectors; p != NULL; p = p->next()) { const char* pname = p->emulation(); if (pname == NULL || strcmp(pname, name) == 0) { Target* ret = p->recognize_by_emulation(name); if (ret != NULL) return ret; } } return NULL; } // Push all the supported BFD names onto a vector. void supported_target_names(std::vector<const char*>* names) { for (Target_selector* p = target_selectors; p != NULL; p = p->next()) p->supported_bfd_names(names); } // Push all the supported emulations onto a vector. void supported_emulation_names(std::vector<const char*>* names) { for (Target_selector* p = target_selectors; p != NULL; p = p->next()) p->supported_emulations(names); } // Implement the --print-output-format option. void print_output_format() { if (!parameters->target_valid()) { // This case arises when --print-output-format is used with no // input files. We need to come up with the right string to // print based on the other options. If the user specified the // format using a --oformat option, use that. That saves each // target from having to remember the name that was used to // select it. In other cases, we will just have to ask the // target. if (parameters->options().user_set_oformat()) { const char* bfd_name = parameters->options().oformat(); Target* target = select_target_by_bfd_name(bfd_name); if (target != NULL) printf("%s\n", bfd_name); else gold_error(_("unrecognized output format %s"), bfd_name); return; } parameters_force_valid_target(); } const Target* target = ¶meters->target(); for (Target_selector* p = target_selectors; p != NULL; p = p->next()) { const char* bfd_name = p->target_bfd_name(target); if (bfd_name != NULL) { printf("%s\n", bfd_name); return; } } gold_unreachable(); } } // End namespace gold.