guile/libguile/smob.h

#ifndef SCM_SMOB_H
#define SCM_SMOB_H

/* Copyright 1995-1996,1998-2001,2004,2006,2009-2012,2015,2018
     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/error.h>
#include <libguile/gc.h>
#include "libguile/inline.h"
#include "libguile/print.h"
#include <libguile/snarf.h>



/* This is the internal representation of a smob type */

typedef struct scm_smob_descriptor
{
  char const *name;
  size_t size;
  SCM (*mark) (SCM);
  size_t (*free) (SCM);
  int (*print) (SCM exp, SCM port, scm_print_state *pstate);
  SCM (*equalp) (SCM, SCM);
  scm_t_subr apply;
  SCM apply_trampoline;
} scm_smob_descriptor;


#define SCM_SMOB_TYPE_MASK		0xffff
#define SCM_SMOB_TYPE_BITS(tc)		(tc)
#define SCM_TC2SMOBNUM(x)		(0x0ff & ((x) >> 8))
#define SCM_SMOBNUM(x)			(SCM_TC2SMOBNUM (SCM_CELL_TYPE (x)))
/* SCM_SMOBNAME can be 0 if name is missing */
#define SCM_SMOBNAME(smobnum)		(scm_smobs[smobnum].name)
#define SCM_SMOB_PREDICATE(tag, obj)	SCM_HAS_TYP16 (obj, tag)
#define SCM_SMOB_DESCRIPTOR(x)		(scm_smobs[SCM_SMOBNUM (x)])
#define SCM_SMOB_APPLICABLE_P(x)	(SCM_SMOB_DESCRIPTOR (x).apply)

#define SCM_VALIDATE_SMOB(pos, obj, type) \
  do { \
    SCM_ASSERT (SCM_SMOB_PREDICATE (scm_tc16_ ## type, obj), \
                obj, pos, FUNC_NAME); \
  } while (0)

/* Maximum number of SMOB types.  */
#define SCM_I_MAX_SMOB_TYPE_COUNT  256

SCM_API long scm_numsmob;
SCM_API scm_smob_descriptor scm_smobs[];




#define SCM_SMOB(tag, scheme_name, size) \
SCM_SNARF_HERE(static scm_t_bits tag) \
SCM_SNARF_INIT((tag)=scm_make_smob_type((scheme_name), (size));)

#define SCM_GLOBAL_SMOB(tag, scheme_name, size) \
SCM_SNARF_HERE(scm_t_bits tag) \
SCM_SNARF_INIT((tag)=scm_make_smob_type((scheme_name), (size));)

#define SCM_SMOB_MARK(tag, c_name, arg) \
SCM_SNARF_HERE(static SCM c_name(SCM arg)) \
SCM_SNARF_INIT(scm_set_smob_mark((tag), (c_name));)

#define SCM_GLOBAL_SMOB_MARK(tag, c_name, arg) \
SCM_SNARF_HERE(SCM c_name(SCM arg)) \
SCM_SNARF_INIT(scm_set_smob_mark((tag), (c_name));)

#define SCM_SMOB_FREE(tag, c_name, arg) \
SCM_SNARF_HERE(static size_t c_name(SCM arg)) \
SCM_SNARF_INIT(scm_set_smob_free((tag), (c_name));)

#define SCM_GLOBAL_SMOB_FREE(tag, c_name, arg) \
SCM_SNARF_HERE(size_t c_name(SCM arg)) \
SCM_SNARF_INIT(scm_set_smob_free((tag), (c_name));)

#define SCM_SMOB_PRINT(tag, c_name, obj, port, pstate) \
SCM_SNARF_HERE(static int c_name(SCM obj, SCM port, scm_print_state* pstate)) \
SCM_SNARF_INIT(scm_set_smob_print((tag), (c_name));)

#define SCM_GLOBAL_SMOB_PRINT(tag, c_name, obj, port, pstate) \
SCM_SNARF_HERE(int c_name(SCM obj, SCM port, scm_print_state* pstate)) \
SCM_SNARF_INIT(scm_set_smob_print((tag), (c_name));)

#define SCM_SMOB_EQUALP(tag, c_name, obj1, obj2) \
SCM_SNARF_HERE(static SCM c_name(SCM obj1, SCM obj2)) \
SCM_SNARF_INIT(scm_set_smob_equalp((tag), (c_name));)

#define SCM_GLOBAL_SMOB_EQUALP(tag, c_name, obj1, obj2) \
SCM_SNARF_HERE(SCM c_name(SCM obj1, SCM obj2)) \
SCM_SNARF_INIT(scm_set_smob_equalp((tag), (c_name));)

#define SCM_SMOB_APPLY(tag, c_name, req, opt, rest, arglist) \
SCM_SNARF_HERE(static SCM c_name arglist) \
SCM_SNARF_INIT(scm_set_smob_apply((tag), (c_name), (req), (opt), (rest));)

#define SCM_GLOBAL_SMOB_APPLY(tag, c_name, req, opt, rest, arglist) \
SCM_SNARF_HERE(SCM c_name arglist) \
SCM_SNARF_INIT(scm_set_smob_apply((tag), (c_name), (req), (opt), (rest));)




SCM_API SCM scm_i_new_smob (scm_t_bits tc, scm_t_bits);
SCM_API SCM scm_i_new_double_smob (scm_t_bits tc, scm_t_bits,
                                   scm_t_bits, scm_t_bits);


SCM_INLINE SCM scm_new_smob (scm_t_bits tc, scm_t_bits);
SCM_INLINE SCM scm_new_double_smob (scm_t_bits tc, scm_t_bits,
                                    scm_t_bits, scm_t_bits);

#if SCM_CAN_INLINE || defined SCM_INLINE_C_IMPLEMENTING_INLINES
SCM_INLINE_IMPLEMENTATION SCM
scm_new_smob (scm_t_bits tc, scm_t_bits data)
{
  scm_t_bits smobnum = SCM_TC2SMOBNUM (tc);

  if (SCM_UNLIKELY (scm_smobs[smobnum].mark || scm_smobs[smobnum].free))
    return scm_i_new_smob (tc, data);
  else
    return scm_cell (tc, data);
}

SCM_INLINE_IMPLEMENTATION SCM
scm_new_double_smob (scm_t_bits tc, scm_t_bits data1,
                     scm_t_bits data2, scm_t_bits data3)
{
  scm_t_bits smobnum = SCM_TC2SMOBNUM (tc);

  if (SCM_UNLIKELY (scm_smobs[smobnum].mark || scm_smobs[smobnum].free))
    return scm_i_new_double_smob (tc, data1, data2, data3);
  else
    return scm_double_cell (tc, data1, data2, data3);
}
#endif

#define SCM_NEWSMOB(z, tc, data)                \
  z = scm_new_smob ((tc), (scm_t_bits)(data))
#define SCM_RETURN_NEWSMOB(tc, data)            \
  return scm_new_smob ((tc), (scm_t_bits)(data))

#define SCM_NEWSMOB2(z, tc, data1, data2)               \
  z = scm_new_double_smob ((tc), (scm_t_bits)(data1),   \
                           (scm_t_bits)(data2), 0)
#define SCM_RETURN_NEWSMOB2(tc, data1, data2)                   \
  return scm_new_double_smob ((tc), (scm_t_bits)(data1),        \
                              (scm_t_bits)(data2), 0)

#define SCM_NEWSMOB3(z, tc, data1, data2, data3)                        \
  z = scm_new_double_smob ((tc), (scm_t_bits)(data1),                   \
                           (scm_t_bits)(data2), (scm_t_bits)(data3))
#define SCM_RETURN_NEWSMOB3(tc, data1, data2, data3)                    \
  return scm_new_double_smob ((tc), (scm_t_bits)(data1),                \
                              (scm_t_bits)(data2), (scm_t_bits)(data3))



#define SCM_SMOB_DATA_N(x, n)		(SCM_CELL_WORD ((x), (n)))
#define SCM_SET_SMOB_DATA_N(x, n, data)	(SCM_SET_CELL_WORD ((x), (n), (data)))

#define SCM_SMOB_DATA_0(x)		(SCM_SMOB_DATA_N ((x), 0))
#define SCM_SMOB_DATA_1(x)		(SCM_SMOB_DATA_N ((x), 1))
#define SCM_SMOB_DATA_2(x)		(SCM_SMOB_DATA_N ((x), 2))
#define SCM_SMOB_DATA_3(x)		(SCM_SMOB_DATA_N ((x), 3))
#define SCM_SET_SMOB_DATA_0(x, data)	(SCM_SET_SMOB_DATA_N ((x), 0, (data)))
#define SCM_SET_SMOB_DATA_1(x, data)	(SCM_SET_SMOB_DATA_N ((x), 1, (data)))
#define SCM_SET_SMOB_DATA_2(x, data)	(SCM_SET_SMOB_DATA_N ((x), 2, (data)))
#define SCM_SET_SMOB_DATA_3(x, data)	(SCM_SET_SMOB_DATA_N ((x), 3, (data)))

#define SCM_SMOB_FLAGS(x)               (SCM_SMOB_DATA_0 (x) >> 16)
#define SCM_SMOB_DATA(x)		(SCM_SMOB_DATA_1 (x))
#define SCM_SET_SMOB_FLAGS(x, data)     (SCM_SET_SMOB_DATA_0 ((x), (SCM_CELL_TYPE (x)&0xffff)|((data)<<16)))
#define SCM_SET_SMOB_DATA(x, data)	(SCM_SET_SMOB_DATA_1 ((x), (data)))

#define SCM_SMOB_OBJECT_N(x,n)		(SCM_CELL_OBJECT ((x), (n)))
#define SCM_SET_SMOB_OBJECT_N(x,n,obj)	(SCM_SET_CELL_OBJECT ((x), (n), (obj)))
#define SCM_SMOB_OBJECT_N_LOC(x,n)	(SCM_CELL_OBJECT_LOC ((x), (n)))

/*#define SCM_SMOB_OBJECT_0(x)		(SCM_SMOB_OBJECT_N ((x), 0))*/
#define SCM_SMOB_OBJECT_1(x)		(SCM_SMOB_OBJECT_N ((x), 1))
#define SCM_SMOB_OBJECT_2(x)		(SCM_SMOB_OBJECT_N ((x), 2))
#define SCM_SMOB_OBJECT_3(x)		(SCM_SMOB_OBJECT_N ((x), 3))
/*#define SCM_SET_SMOB_OBJECT_0(x,obj)	(SCM_SET_SMOB_OBJECT_N ((x), 0, (obj)))*/
#define SCM_SET_SMOB_OBJECT_1(x,obj)	(SCM_SET_SMOB_OBJECT_N ((x), 1, (obj)))
#define SCM_SET_SMOB_OBJECT_2(x,obj)	(SCM_SET_SMOB_OBJECT_N ((x), 2, (obj)))
#define SCM_SET_SMOB_OBJECT_3(x,obj)	(SCM_SET_SMOB_OBJECT_N ((x), 3, (obj)))
#define SCM_SMOB_OBJECT_0_LOC(x)	(SCM_SMOB_OBJECT_N_LOC ((x), 0))
#define SCM_SMOB_OBJECT_1_LOC(x)	(SCM_SMOB_OBJECT_N_LOC ((x), 1))
#define SCM_SMOB_OBJECT_2_LOC(x)	(SCM_SMOB_OBJECT_N_LOC ((x), 2))
#define SCM_SMOB_OBJECT_3_LOC(x)	(SCM_SMOB_OBJECT_N_LOC ((x), 3))

#define SCM_SMOB_OBJECT(x)		(SCM_SMOB_OBJECT_1 (x))
#define SCM_SET_SMOB_OBJECT(x,obj)	(SCM_SET_SMOB_OBJECT_1 ((x), (obj)))
#define SCM_SMOB_OBJECT_LOC(x)		(SCM_SMOB_OBJECT_1_LOC (x))


#define SCM_SMOB_APPLY_0(x)		(scm_call_0 (x))
#define SCM_SMOB_APPLY_1(x, a1)		(scm_call_1 (x, a1))
#define SCM_SMOB_APPLY_2(x, a1, a2)	(scm_call_2 (x, a1, a2))
#define SCM_SMOB_APPLY_3(x, a1, a2, rst) (scm_call_3 (x, a1, a2, a3))



SCM_API SCM scm_mark0 (SCM ptr);
SCM_API SCM scm_markcdr (SCM ptr);
SCM_API size_t scm_free0 (SCM ptr);
SCM_API int scm_smob_print (SCM exp, SCM port, scm_print_state *pstate);

/* The following set of functions is the standard way to create new
 * SMOB types.
 *
 * Create a type tag using `scm_make_smob_type', accept default values
 * for mark, free, print and/or equalp functions, or set your own
 * values using `scm_set_smob_xxx'.
 */

SCM_API scm_t_bits scm_make_smob_type (char const *name, size_t size);

SCM_API void scm_set_smob_mark (scm_t_bits tc, SCM (*mark) (SCM));
SCM_API void scm_set_smob_free (scm_t_bits tc, size_t (*free) (SCM));
SCM_API void scm_set_smob_print (scm_t_bits tc,
				 int (*print) (SCM, SCM, scm_print_state*));
SCM_API void scm_set_smob_equalp (scm_t_bits tc, SCM (*equalp) (SCM, SCM));
SCM_API void scm_set_smob_apply (scm_t_bits tc,
				 scm_t_subr apply,
				 unsigned int req,
				 unsigned int opt,
				 unsigned int rst);

SCM_API SCM scm_smob_type_class (scm_t_bits tc);

SCM_API void scm_assert_smob_type (scm_t_bits tag, SCM val);

/* Function for creating smobs */

SCM_API SCM scm_make_smob (scm_t_bits tc);

SCM_API void scm_smob_prehistory (void);

#endif  /* SCM_SMOB_H */