Subversion Repositories openrisc_2011-10-31

// freebsd.h -- FreeBSD support for gold    -*- C++ -*-

// Copyright 2009 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 "target.h"

#include "target-select.h"

#ifndef GOLD_FREEBSD_H

#define GOLD_FREEBSD_H

namespace gold

{

// FreeBSD 4.1 and later wants the EI_OSABI field in the ELF header to

// be set to ELFOSABI_FREEBSD.  This is a subclass of Sized_target

// which supports that.  The real target would be a subclass of this

// one.  We permit combining FreeBSD and non-FreeBSD object files.

// The effect of this target is to set the code in the output file.

template<int size, bool big_endian>

class Target_freebsd : public Sized_target<size, big_endian>

{

 public:

  // Set the value to use for the EI_OSABI field in the ELF header.

  void

  set_osabi(elfcpp::ELFOSABI osabi)

  { this->osabi_ = osabi; }

 protected:

  Target_freebsd(const Target::Target_info* pti)

    : Sized_target<size, big_endian>(pti),

      osabi_(elfcpp::ELFOSABI_NONE)

  { }

  virtual void

  do_adjust_elf_header(unsigned char* view, int len) const;

 private:

  // Value to store in the EI_OSABI field of the ELF file header.

  elfcpp::ELFOSABI osabi_;

};

// Adjust the ELF file header by storing the requested value in the

// OSABI field.  This is for FreeBSD support.

template<int size, bool big_endian>

inline void

Target_freebsd<size, big_endian>::do_adjust_elf_header(unsigned char* view,

                                                       int len) const

{

  if (this->osabi_ != elfcpp::ELFOSABI_NONE)

    {

      gold_assert(len == elfcpp::Elf_sizes<size>::ehdr_size);

      elfcpp::Ehdr<size, false> ehdr(view);

      unsigned char e_ident[elfcpp::EI_NIDENT];

      memcpy(e_ident, ehdr.get_e_ident(), elfcpp::EI_NIDENT);

      e_ident[elfcpp::EI_OSABI] = this->osabi_;

      elfcpp::Ehdr_write<size, false> oehdr(view);

      oehdr.put_e_ident(e_ident);

    }

}

// A target selector for targets which permit combining both FreeBSD

// and non-FreeBSD object files.

class Target_selector_freebsd : public Target_selector

{

 public:

  Target_selector_freebsd(int machine, int size, bool is_big_endian,

                          const char* bfd_name,

                          const char* freebsd_bfd_name)

    : Target_selector(machine, size, is_big_endian, NULL),

      bfd_name_(bfd_name), freebsd_bfd_name_(freebsd_bfd_name)

  { }

 protected:

  // If we see a FreeBSD input file, mark the output file as using

  // FreeBSD.

  virtual Target*

  do_recognize(int, int osabi, int)

  {

    Target* ret = this->instantiate_target();

    if (osabi == elfcpp::ELFOSABI_FREEBSD)

      this->set_osabi(ret);

    return ret;

  }

  // Recognize two names.

  virtual Target*

  do_recognize_by_name(const char* name)

  {

    if (strcmp(name, this->bfd_name_) == 0)

      return this->instantiate_target();

    else if (strcmp(name, this->freebsd_bfd_name_) == 0)

      {

        Target* ret = this->instantiate_target();

        this->set_osabi(ret);

        return ret;

      }

    else

      return NULL;

  }

  // Print both names in --help output.

  virtual void

  do_supported_names(std::vector<const char*>* names)

  {

    names->push_back(this->bfd_name_);

    names->push_back(this->freebsd_bfd_name_);

  }

 private:

  // Set the OSABI field.  This is quite ugly.

  void

  set_osabi(Target* target)

  {

    if (this->get_size() == 32)

      {

        if (this->is_big_endian())

          static_cast<Target_freebsd<32, true>*>(target)->

            set_osabi(elfcpp::ELFOSABI_FREEBSD);

        else

          static_cast<Target_freebsd<32, false>*>(target)->

            set_osabi(elfcpp::ELFOSABI_FREEBSD);

      }

    else if (this->get_size() == 64)

      {

        if (this->is_big_endian())

          static_cast<Target_freebsd<64, true>*>(target)->

            set_osabi(elfcpp::ELFOSABI_FREEBSD);

        else

          static_cast<Target_freebsd<64, false>*>(target)->

            set_osabi(elfcpp::ELFOSABI_FREEBSD);

      }

    else

      gold_unreachable();

  }

  // The BFD name for the non-Freebsd target.

  const char* bfd_name_;

  // The BFD name for the Freebsd target.

  const char* freebsd_bfd_name_;

};

} // end namespace gold

#endif // !defined(GOLD_FREEBSD_H)