#ifndef SCM_SMOB_INTERNAL_H
#define SCM_SMOB_INTERNAL_H

/* Copyright 1995-1996,1998-2001,2004,2006,2009-2012,2015,2018,2025
     Free Software Foundation, Inc.

   This file is part of Guile.

   Guile is free software: you can redistribute it and/or modify it
   under the terms of 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.

   Guile 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 Lesser General Public
   License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with Guile.  If not, see
   <https://www.gnu.org/licenses/>.  */



#include "libguile/smob.h"



struct scm_smob
{
  scm_t_bits tag_and_flags;
};

struct scm_single_smob
{
  struct scm_smob header;
  scm_t_bits data_1;
};

struct scm_double_smob
{
  struct scm_smob header;
  scm_t_bits data_1;
  scm_t_bits data_2;
  scm_t_bits data_3;
};

static inline int
scm_is_smob (SCM x)
{
  return SCM_HAS_TYP7 (x, scm_tc7_smob);
}

static inline struct scm_smob *
scm_to_smob (SCM x)
{
  if (!scm_is_smob (x))
    abort ();
  return (struct scm_smob *) SCM_UNPACK_POINTER (x);
}

static inline SCM
scm_from_smob (struct scm_smob * x)
{
  return SCM_PACK_POINTER (x);
}

static inline struct scm_smob_descriptor *
scm_i_smob_descriptor (struct scm_smob *x)
{
  return &scm_smobs[((x->tag_and_flags) & 0xff00) >> 8];
}

static inline int
scm_smob_field_is_managed (const struct scm_smob_descriptor *desc, size_t i)
{
  if (i >= 32)
    abort();

  return ((1 << i) & desc->unmanaged_fields) == 0;
}

static inline int
scm_smob_field_is_unmanaged (const struct scm_smob_descriptor *desc, size_t i)
{
  return !scm_smob_field_is_managed (desc, i);
}

static inline void*
scm_smob_field_loc (struct scm_smob *smob, size_t i)
{
  uintptr_t addr = (uintptr_t) smob;
  return (void *) (addr + sizeof (*smob) + i * sizeof (scm_t_bits));
}

SCM_INTERNAL void scm_i_finalize_smob (struct scm_thread *thread, SCM obj);

#endif  /* SCM_SMOB_INTERNAL_H */