/* Return build ID information for a module.

   Copyright (C) 2007-2010, 2014 Red Hat, Inc.

   This file is part of elfutils.

   This file is free software; you can redistribute it and/or modify

   it under the terms of either

     * the GNU Lesser General Public License as published by the Free

       Software Foundation; either version 3 of the License, or (at

       your option) any later version

   or

     * the GNU General Public License as published by the Free

       Software Foundation; either version 2 of the License, or (at

       your option) any later version

   or both in parallel, as here.

   elfutils 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 copies of the GNU General Public License and

   the GNU Lesser General Public License along with this program.  If

   not, see <http://www.gnu.org/licenses/>.  */

#ifdef HAVE_CONFIG_H

# include <config.h>

#endif

#include "libdwflP.h"

static int

found_build_id (Dwfl_Module *mod, bool set,

		const void *bits, int len, GElf_Addr vaddr)

{

  if (!set)

    /* When checking bits, we do not compare VADDR because the

       address found in a debuginfo file may not match the main

       file as modified by prelink.  */

    return 1 + (mod->build_id_len == len

		&& !memcmp (bits, mod->build_id_bits, len));

  void *copy = malloc (len);

  if (unlikely (copy == NULL))

    {

      __libdwfl_seterrno (DWFL_E_NOMEM);

      return -1;

    }

  mod->build_id_bits = memcpy (copy, bits, len);

  mod->build_id_vaddr = vaddr;

  mod->build_id_len = len;

  return len;

}

int

internal_function

__libdwfl_find_build_id (Dwfl_Module *mod, bool set, Elf *elf)

{

  const void *build_id_bits;

  GElf_Addr build_id_elfaddr;

  int build_id_len;

  /* For mod == NULL use dwelf_elf_gnu_build_id directly.  */

  assert (mod != NULL);

  int result = __libdwfl_find_elf_build_id (mod, elf, &build_id_bits,

					    &build_id_elfaddr, &build_id_len);

  if (result <= 0)

    return result;

  GElf_Addr build_id_vaddr = build_id_elfaddr + (build_id_elfaddr != 0

						 ? mod->main_bias : 0);

  return found_build_id (mod, set, build_id_bits, build_id_len, build_id_vaddr);

}

int

dwfl_module_build_id (Dwfl_Module *mod,

		      const unsigned char **bits, GElf_Addr *vaddr)

{

  if (mod == NULL)

    return -1;

  if (mod->build_id_len == 0 && mod->main.elf != NULL)

    {

      /* We have the file, but have not examined it yet.  */

      int result = __libdwfl_find_build_id (mod, true, mod->main.elf);

      if (result <= 0)

	{

	  mod->build_id_len = -1;	/* Cache negative result.  */

	  return result;

	}

    }

  if (mod->build_id_len <= 0)

    return 0;

  *bits = mod->build_id_bits;

  *vaddr = mod->build_id_vaddr;

  return mod->build_id_len;

}

INTDEF (dwfl_module_build_id)

NEW_VERSION (dwfl_module_build_id, ELFUTILS_0.138)

#ifdef SYMBOL_VERSIONING

COMPAT_VERSION (dwfl_module_build_id, ELFUTILS_0.130, vaddr_at_end)

int

_compat_vaddr_at_end_dwfl_module_build_id (Dwfl_Module *mod,

					   const unsigned char **bits,

					   GElf_Addr *vaddr)

{

  int result = INTUSE(dwfl_module_build_id) (mod, bits, vaddr);

  if (result > 0)

    *vaddr += (result + 3) & -4;

  return result;

}

#endif