libelf/elf_next.c

/* Advance in archive to next element.
   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
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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 <assert.h>
#include <libelf.h>
#include <stddef.h>

#include "libelfP.h"


Elf_Cmd
elf_next (elf)
     Elf *elf;
{
  Elf *parent;
  Elf_Cmd ret;

  /* Be gratious, the specs demand it.  */
  if (elf == NULL || elf->parent == NULL)
    return ELF_C_NULL;

  /* We can be sure the parent is an archive.  */
  parent = elf->parent;
  assert (parent->kind == ELF_K_AR);

  rwlock_wrlock (parent->lock);

  /* Now advance the offset.  */
  parent->state.ar.offset += (sizeof (struct ar_hdr)
			      + ((parent->state.ar.elf_ar_hdr.ar_size + 1)
				 & ~1l));

  /* Get the next archive header.  */
  ret = __libelf_next_arhdr_wrlock (parent) != 0 ? ELF_C_NULL : elf->cmd;

  rwlock_unlock (parent->lock);

  return ret;
}