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// nacl.h -- Native Client support for gold -*- C++ -*-
// Copyright (C) 2012-2019 Free Software Foundation, Inc.
// 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 "elfcpp_file.h"
#include "fileread.h"
#include "layout.h"
#include "target-select.h"
#include "target.h"
#ifndef GOLD_NACL_H
#define GOLD_NACL_H
namespace gold
{
class Sniff_file
{
public:
Sniff_file(Input_file* input_file, off_t offset)
: file_(input_file->file()), offset_(offset)
{ }
class Location
{
public:
Location(off_t file_offset, off_t data_size)
: offset_(file_offset), size_(data_size)
{ }
inline off_t offset() const
{ return this->offset_; }
inline section_size_type size() const
{ return this->size_; }
private:
off_t offset_;
section_size_type size_;
};
class View
{
public:
View(File_read& file, off_t file_offset, off_t data_size)
: data_(file.get_view(file_offset, 0, data_size, true, false))
{ }
const unsigned char* data()
{ return this->data_; }
private:
const unsigned char* data_;
};
View view(off_t file_offset, off_t data_size)
{
return View(this->file_, this->offset_ + file_offset, data_size);
}
View view(Location loc)
{
return this->view(loc.offset(), loc.size());
}
// Report an error.
void
error(const char* format, ...) const ATTRIBUTE_PRINTF_2;
private:
File_read& file_;
off_t offset_;
};
template<class base_selector, class nacl_target>
class Target_selector_nacl : public base_selector
{
public:
Target_selector_nacl(const char* nacl_abi_name,
const char* bfd_name, const char* emulation)
: base_selector(), is_nacl_(false), nacl_abi_name_(nacl_abi_name),
bfd_name_(bfd_name), emulation_(emulation)
{ }
protected:
virtual Target*
do_instantiate_target()
{
if (this->is_nacl_)
return new nacl_target();
return this->base_selector::do_instantiate_target();
}
virtual Target*
do_recognize(Input_file* file, off_t offset,
int machine, int osabi, int abiversion)
{
this->is_nacl_ = file != NULL && this->recognize_nacl_file(file, offset);
if (this->is_nacl_)
return this->instantiate_target();
return this->base_selector::do_recognize(file, offset,
machine, osabi, abiversion);
}
virtual Target*
do_recognize_by_bfd_name(const char* name)
{
gold_assert(this->bfd_name_ != NULL);
this->is_nacl_ = strcmp(name, this->bfd_name_) == 0;
if (this->is_nacl_)
return this->instantiate_target();
return this->base_selector::do_recognize_by_bfd_name(name);
}
virtual void
do_supported_bfd_names(std::vector<const char*>* names)
{
gold_assert(this->bfd_name_ != NULL);
this->base_selector::do_supported_bfd_names(names);
names->push_back(this->bfd_name_);
}
virtual void
do_supported_emulations(std::vector<const char*>* emulations)
{
gold_assert(this->emulation_ != NULL);
this->base_selector::do_supported_emulations(emulations);
emulations->push_back(this->emulation_);
}
virtual const char*
do_target_bfd_name(const Target* target)
{
return (!this->is_our_target(target)
? NULL
: (this->is_nacl_
? this->bfd_name_
: base_selector::do_target_bfd_name(target)));
}
private:
bool
recognize_nacl_file(Input_file* input_file, off_t offset)
{
if (this->is_big_endian())
{
#if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
# ifdef HAVE_TARGET_32_BIG
if (this->get_size() == 32)
return do_recognize_nacl_file<32, true>(input_file, offset);
# endif
# ifdef HAVE_TARGET_64_BIG
if (this->get_size() == 64)
return do_recognize_nacl_file<64, true>(input_file, offset);
# endif
#endif
gold_unreachable();
}
else
{
#if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
# ifdef HAVE_TARGET_32_LITTLE
if (this->get_size() == 32)
return do_recognize_nacl_file<32, false>(input_file, offset);
# endif
# ifdef HAVE_TARGET_64_LITTLE
if (this->get_size() == 64)
return do_recognize_nacl_file<64, false>(input_file, offset);
# endif
#endif
gold_unreachable();
}
}
template<int size, bool big_endian>
bool
do_recognize_nacl_file(Input_file* input_file, off_t offset)
{
Sniff_file file(input_file, offset);
elfcpp::Elf_file<size, big_endian, Sniff_file> elf_file(&file);
const unsigned int shnum = elf_file.shnum();
for (unsigned int shndx = 1; shndx < shnum; ++shndx)
{
if (elf_file.section_type(shndx) == elfcpp::SHT_NOTE)
{
Sniff_file::Location loc = elf_file.section_contents(shndx);
if (loc.size() < (3 * 4
+ align_address(sizeof "NaCl", 4)
+ align_address(nacl_abi_name_.size() + 1, 4)))
continue;
Sniff_file::View view(file.view(loc));
const unsigned char* note_data = view.data();
if ((elfcpp::Swap<32, big_endian>::readval(note_data + 0)
== sizeof "NaCl")
&& (elfcpp::Swap<32, big_endian>::readval(note_data + 4)
== nacl_abi_name_.size() + 1)
&& (elfcpp::Swap<32, big_endian>::readval(note_data + 8)
== elfcpp::NT_VERSION))
{
const unsigned char* name = note_data + 12;
const unsigned char* desc = (name
+ align_address(sizeof "NaCl", 4));
if (memcmp(name, "NaCl", sizeof "NaCl") == 0
&& memcmp(desc, nacl_abi_name_.c_str(),
nacl_abi_name_.size() + 1) == 0)
return true;
}
}
}
return false;
}
// Whether we decided this was the NaCl target variant.
bool is_nacl_;
// The string found in the NaCl ABI note.
std::string nacl_abi_name_;
// BFD name of NaCl target, for compatibility.
const char* const bfd_name_;
// GNU linker emulation for this NaCl target, for compatibility.
const char* const emulation_;
};
} // end namespace gold
#endif // !defined(GOLD_NACL_H)
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