libelf/elf_rand.c

/* Select specific element in archive.
   Copyright (C) 1998, 1999, 2000, 2002 Red Hat, Inc.
   This file is part of Red Hat elfutils.
   Contributed by Ulrich Drepper <drepper@redhat.com>, 1998.

   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.

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   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
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#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <libelf.h>
#include <stddef.h>

#include "libelfP.h"


size_t
elf_rand (elf, offset)
     Elf *elf;
     size_t offset;
{
  /* Be gratious, the specs demand it.  */
  if (elf == NULL || elf->kind != ELF_K_AR)
    return 0;

  rwlock_wrlock (elf->lock);

  /* Save the old offset and set the offset.  */
  elf->state.ar.offset = elf->start_offset + offset;

  /* Get the next archive header.  */
  if (__libelf_next_arhdr_wrlock (elf) != 0)
    {
      /* Mark the archive header as unusable.  */
      elf->state.ar.elf_ar_hdr.ar_name = NULL;
      return 0;
    }

  rwlock_unlock (elf->lock);

  return offset;
}