libelf/elf_clone.c

/* Create clone of a given descriptor.
   Copyright (C) 2003, 2004 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.

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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

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   with Red Hat elfutils; if not, write to the Free Software Foundation,
   Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.

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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
   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 <stddef.h>
#include "libelfP.h"
#include "common.h"


Elf *
elf_clone (Elf *elf, Elf_Cmd cmd)
{
  Elf *retval = NULL;

  if (elf == NULL)
    /* Some earlier mistake.  */
    return NULL;

  /* Make sure the descriptor is not suddenly going away.  */
  rwlock_rdlock (elf->lock);

  if (cmd != ELF_C_EMPTY)
    // XXX TODO handle ELF_C_READ/WRITE etc
    goto out;

  retval = allocate_elf (elf->fildes, elf->map_address, elf->start_offset,
			 elf->maximum_size, elf->cmd, elf->parent, elf->kind,
			 elf->state.elf32.scns.max * sizeof (Elf_Scn));
  if (retval != NULL)
    {
      /* We have to write to the file in any case.  */
      retval->flags = ELF_F_DIRTY;

      /* Some more or less arbitrary value.  */
      retval->state.elf.scnincr = 10;

      /* We have allocated room for some sections.  */
      assert (offsetof (struct Elf, state.elf32.scns)
	      == offsetof (struct Elf, state.elf64.scns));
      retval->state.elf.scns_last = &retval->state.elf32.scns;
      retval->state.elf32.scns.max = elf->state.elf32.scns.max;

      retval->class = elf->class;
    }

  /* Release the lock.  */
 out:
  rwlock_unlock (elf->lock);

  return retval;
}