xref: /external/elfutils/0.153/libdw/dwarf_getabbrevattr.c

/* Get specific attribute of abbreviation.
   Copyright (C) 2003, 2004, 2005 Red Hat, Inc.
   This file is part of Red Hat elfutils.
   Written by Ulrich Drepper <drepper@redhat.com>, 2003.

   Red Hat elfutils 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; version 2 of the License.

   Red Hat 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 a copy of the GNU General Public License along
   with Red Hat elfutils; if not, write to the Free Software Foundation,
   Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.

   In addition, as a special exception, Red Hat, Inc. gives You the
   additional right to link the code of Red Hat elfutils with code licensed
   under any Open Source Initiative certified open source license
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   this exception must only link to the code of Red Hat elfutils through
   those well defined interfaces identified in the file named EXCEPTION
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   Red Hat's grant of this exception is conditioned upon your not adding
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   exception, please contact Red Hat.  You must obey the GNU General Public
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   code used in conjunction with Red Hat elfutils except the Non-GPL Code
   covered by this exception.  If you modify this file, you may extend this
   exception to your version of the file, but you are not obligated to do
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   this file solely under the GPL without exception.

   Red Hat elfutils is an included package of the Open Invention Network.
   An included package of the Open Invention Network is a package for which
   Open Invention Network licensees cross-license their patents.  No patent
   license is granted, either expressly or impliedly, by designation as an
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#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <assert.h>
#include <dwarf.h>
#include "libdwP.h"


int
dwarf_getabbrevattr (abbrev, idx, namep, formp, offsetp)
     Dwarf_Abbrev *abbrev;
     size_t idx;
     unsigned int *namep;
     unsigned int *formp;
     Dwarf_Off *offsetp;
{
  if (abbrev == NULL)
    return -1;

  size_t cnt = 0;
  const unsigned char *attrp = abbrev->attrp;
  const unsigned char *start_attrp;
  unsigned int name;
  unsigned int form;

  do
    {
      start_attrp = attrp;

      /* Attribute code and form are encoded as ULEB128 values.  */
      get_uleb128 (name, attrp);
      get_uleb128 (form, attrp);

      /* If both values are zero the index is out of range.  */
      if (name == 0 && form == 0)
	return -1;
    }
  while (cnt++ < idx);

  /* Store the result if requested.  */
  if (namep != NULL)
    *namep = name;
  if (formp != NULL)
    *formp = form;
  if (offsetp != NULL)
    *offsetp = (start_attrp - abbrev->attrp) + abbrev->offset;

  return 0;
}