| 1 | // target-select.cc -- select a target for an object file |
| 2 | |
| 3 | // Copyright 2006, 2007, 2008 Free Software Foundation, Inc. |
| 4 | // Written by Ian Lance Taylor <iant@google.com>. |
| 5 | |
| 6 | // This file is part of gold. |
| 7 | |
| 8 | // This program is free software; you can redistribute it and/or modify |
| 9 | // it under the terms of the GNU General Public License as published by |
| 10 | // the Free Software Foundation; either version 3 of the License, or |
| 11 | // (at your option) any later version. |
| 12 | |
| 13 | // This program is distributed in the hope that it will be useful, |
| 14 | // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | // GNU General Public License for more details. |
| 17 | |
| 18 | // You should have received a copy of the GNU General Public License |
| 19 | // along with this program; if not, write to the Free Software |
| 20 | // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
| 21 | // MA 02110-1301, USA. |
| 22 | |
| 23 | #include "gold.h" |
| 24 | |
| 25 | #include <cstring> |
| 26 | |
| 27 | #include "elfcpp.h" |
| 28 | #include "target-select.h" |
| 29 | |
| 30 | namespace |
| 31 | { |
| 32 | |
| 33 | // The start of the list of target selectors. |
| 34 | |
| 35 | gold::Target_selector* target_selectors; |
| 36 | |
| 37 | } // End anonymous namespace. |
| 38 | |
| 39 | namespace gold |
| 40 | { |
| 41 | |
| 42 | // Construct a Target_selector, which means adding it to the linked |
| 43 | // list. This runs at global constructor time, so we want it to be |
| 44 | // fast. |
| 45 | |
| 46 | Target_selector::Target_selector(int machine, int size, bool is_big_endian, |
| 47 | const char* bfd_name) |
| 48 | : machine_(machine), size_(size), is_big_endian_(is_big_endian), |
| 49 | bfd_name_(bfd_name), instantiated_target_(NULL), lock_(NULL), |
| 50 | initialize_lock_(&this->lock_) |
| 51 | |
| 52 | { |
| 53 | this->next_ = target_selectors; |
| 54 | target_selectors = this; |
| 55 | } |
| 56 | |
| 57 | // Instantiate the target and return it. Use a lock to avoid |
| 58 | // instantiating two instances of the same target. |
| 59 | |
| 60 | Target* |
| 61 | Target_selector::instantiate_target() |
| 62 | { |
| 63 | // We assume that the pointer will either be written entirely or not |
| 64 | // at all. |
| 65 | if (this->instantiated_target_ == NULL) |
| 66 | { |
| 67 | this->initialize_lock_.initialize(); |
| 68 | Hold_optional_lock hl(this->lock_); |
| 69 | if (this->instantiated_target_ == NULL) |
| 70 | this->instantiated_target_ = this->do_instantiate_target(); |
| 71 | } |
| 72 | return this->instantiated_target_; |
| 73 | } |
| 74 | |
| 75 | // Find the target for an ELF file. |
| 76 | |
| 77 | Target* |
| 78 | select_target(int machine, int size, bool is_big_endian, int osabi, |
| 79 | int abiversion) |
| 80 | { |
| 81 | for (Target_selector* p = target_selectors; p != NULL; p = p->next()) |
| 82 | { |
| 83 | int pmach = p->machine(); |
| 84 | if ((pmach == machine || pmach == elfcpp::EM_NONE) |
| 85 | && p->get_size() == size |
| 86 | && (p->is_big_endian() ? is_big_endian : !is_big_endian)) |
| 87 | { |
| 88 | Target* ret = p->recognize(machine, osabi, abiversion); |
| 89 | if (ret != NULL) |
| 90 | return ret; |
| 91 | } |
| 92 | } |
| 93 | return NULL; |
| 94 | } |
| 95 | |
| 96 | // Find a target using a BFD name. This is used to support the |
| 97 | // --oformat option. |
| 98 | |
| 99 | Target* |
| 100 | select_target_by_name(const char* name) |
| 101 | { |
| 102 | for (Target_selector* p = target_selectors; p != NULL; p = p->next()) |
| 103 | { |
| 104 | const char* pname = p->bfd_name(); |
| 105 | if (pname == NULL || strcmp(pname, name) == 0) |
| 106 | { |
| 107 | Target* ret = p->recognize_by_name(name); |
| 108 | if (ret != NULL) |
| 109 | return ret; |
| 110 | } |
| 111 | } |
| 112 | return NULL; |
| 113 | } |
| 114 | |
| 115 | // Push all the supported BFD names onto a vector. |
| 116 | |
| 117 | void |
| 118 | supported_target_names(std::vector<const char*>* names) |
| 119 | { |
| 120 | for (Target_selector* p = target_selectors; p != NULL; p = p->next()) |
| 121 | p->supported_names(names); |
| 122 | } |
| 123 | |
| 124 | } // End namespace gold. |