-/* classes: h_files */
-
-#ifndef STRUCTH
-#define STRUCTH
-/* Copyright (C) 1995, 1997, 1999, 2000 Free Software Foundation, Inc.
- *
- * This program 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; either version 2, or (at your option)
- * any later version.
- *
- * This program 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this software; see the file COPYING. If not, write to
- * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
- * Boston, MA 02111-1307 USA
- *
- * As a special exception, the Free Software Foundation gives permission
- * for additional uses of the text contained in its release of GUILE.
- *
- * The exception is that, if you link the GUILE library with other files
- * to produce an executable, this does not by itself cause the
- * resulting executable to be covered by the GNU General Public License.
- * Your use of that executable is in no way restricted on account of
- * linking the GUILE library code into it.
- *
- * This exception does not however invalidate any other reasons why
- * the executable file might be covered by the GNU General Public License.
- *
- * This exception applies only to the code released by the
- * Free Software Foundation under the name GUILE. If you copy
- * code from other Free Software Foundation releases into a copy of
- * GUILE, as the General Public License permits, the exception does
- * not apply to the code that you add in this way. To avoid misleading
- * anyone as to the status of such modified files, you must delete
- * this exception notice from them.
- *
- * If you write modifications of your own for GUILE, it is your choice
- * whether to permit this exception to apply to your modifications.
- * If you do not wish that, delete this exception notice. */
-
-/* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
- gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
-\f
-
-#include "libguile/__scm.h"
-#include "libguile/print.h"
-
-\f
-
-/* Number of words with negative index */
-#define scm_struct_n_extra_words 4
-#define scm_struct_entity_n_extra_words 6
-
-/* These are how the initial words of a vtable are allocated. */
-#define scm_struct_i_setter -6 /* Setter */
-#define scm_struct_i_procedure -5 /* Optional procedure slot */
-#define scm_struct_i_free -4 /* Destructor */
-#define scm_struct_i_ptr -3 /* Start of block (see alloc_struct) */
-#define scm_struct_i_n_words -2 /* How many words allocated to this struct? */
-#define scm_struct_i_size -1 /* Instance size */
-#define scm_struct_i_flags -1 /* Upper 12 bits used as flags */
-#define scm_vtable_index_layout 0 /* A symbol describing the physical arrangement of this type. */
-#define scm_vtable_index_vcell 1 /* An opaque word, managed by the garbage collector. */
-#define scm_vtable_index_vtable 2 /* A pointer to the handle for this vtable. */
-#define scm_vtable_index_printer 3 /* A printer for this struct type. */
-#define scm_vtable_offset_user 4 /* Where do user fields start? */
-
-typedef scm_sizet (*scm_struct_free_t) (SCM *vtable, SCM *data);
-
-#define SCM_STRUCTF_MASK (0xFFF << 20)
-#define SCM_STRUCTF_ENTITY (1L << 30) /* Indicates presence of proc slots */
-#define SCM_STRUCTF_LIGHT (1L << 31) /* Light representation
- (no hidden words) */
-
-#define SCM_STRUCTP(X) (SCM_NIMP(X) && (SCM_TYP3(X) == scm_tc3_cons_gloc))
-#define SCM_STRUCT_DATA(X) ((scm_bits_t *) SCM_CELL_WORD_1 (X))
-#define SCM_STRUCT_VTABLE_DATA(X) ((scm_bits_t *) (SCM_CELL_WORD_0 (X) - 1))
-
-#define SCM_STRUCT_LAYOUT(X) (SCM_PACK (SCM_STRUCT_VTABLE_DATA (X) [scm_vtable_index_layout]))
-#define SCM_SET_STRUCT_LAYOUT(X, v) (SCM_STRUCT_VTABLE_DATA (X) [scm_vtable_index_layout] = SCM_UNPACK (v))
-
-#define SCM_STRUCT_VTABLE(X) (SCM_PACK (SCM_STRUCT_VTABLE_DATA (X) [scm_vtable_index_vtable]))
-#define SCM_STRUCT_PRINTER(X) (SCM_PACK (SCM_STRUCT_VTABLE_DATA (X) [scm_vtable_index_printer]))
-#define SCM_SET_VTABLE_DESTRUCTOR(X, D) (SCM_STRUCT_DATA(X)[scm_struct_i_free] = (SCM) D)
-/* Efficiency is important in the following macro, since it's used in GC */
-#define SCM_LAYOUT_TAILP(X) (((X) & 32) == 0) /* R, W or O */
-
-#define SCM_STRUCT_TABLE_NAME(X) SCM_CAR (X)
-#define SCM_SET_STRUCT_TABLE_NAME(X, NAME) SCM_SETCAR (X, NAME)
-#define SCM_STRUCT_TABLE_CLASS(X) SCM_CDR (X)
-#define SCM_SET_STRUCT_TABLE_CLASS(X, CLASS) SCM_SETCDR (X, CLASS)
-extern SCM scm_struct_table;
-
-\f
-
-extern SCM *scm_alloc_struct (int n_words,
- int n_extra,
- char *who);
-extern scm_sizet scm_struct_free_0 (SCM *vtable, SCM *data);
-extern scm_sizet scm_struct_free_light (SCM *vtable, SCM *data);
-extern scm_sizet scm_struct_free_standard (SCM *vtable, SCM *data);
-extern scm_sizet scm_struct_free_entity (SCM *vtable, SCM *data);
-extern void scm_struct_init (SCM handle, int tail_elts, SCM inits);
-extern SCM scm_make_struct_layout (SCM fields);
-extern SCM scm_struct_p (SCM x);
-extern SCM scm_struct_vtable_p (SCM x);
-extern SCM scm_make_struct (SCM vtable, SCM tail_array_size, SCM init);
-extern SCM scm_make_vtable_vtable (SCM extra_fields, SCM tail_array_size, SCM init);
-extern SCM scm_struct_ref (SCM handle, SCM pos);
-extern SCM scm_struct_set_x (SCM handle, SCM pos, SCM val);
-extern SCM scm_struct_vtable (SCM handle);
-extern SCM scm_struct_vtable_tag (SCM handle);
-extern unsigned int scm_struct_ihashq (SCM obj, unsigned int n);
-extern SCM scm_struct_create_handle (SCM obj);
-extern SCM scm_struct_vtable_name (SCM vtable);
-extern SCM scm_set_struct_vtable_name_x (SCM vtable, SCM name);
-extern void scm_print_struct (SCM exp, SCM port, scm_print_state *);
-extern void scm_init_struct (void);
-
-#endif /* STRUCTH */
-
-/*
- Local Variables:
- c-file-style: "gnu"
- End:
-*/
+/* classes: h_files */
+
+#ifndef SCM_STRUCT_H
+#define SCM_STRUCT_H
+
+/* Copyright (C) 1995,1997,1999,2000,2001, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.
+ *
+ * This library 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.
+ *
+ * This library 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+\f
+
+#include "libguile/__scm.h"
+#include "libguile/print.h"
+
+\f
+
+/* The relationship between a struct and its vtable is a bit complicated,
+ because we want structs to be used as GOOPS' native representation -- which
+ in turn means we need support for changing the "class" (vtable) of an
+ "instance" (struct). This necessitates some indirection and trickery.
+
+ To summarize, structs are laid out this way:
+
+ .-------.
+ | |
+ .----------------+---v------------- -
+ | vtable | data | slot0 | slot1 |
+ `----------------+----------------- -
+ | .-------.
+ | | |
+ .---v------------+---v------------- -
+ | vtable | data | slot0 | slot1 |
+ `----------------+----------------- -
+ |
+ v
+
+ ...
+ .-------.
+ | | |
+ .---v------------+---v------------- -
+ .-| vtable | data | slot0 | slot1 |
+ | `----------------+----------------- -
+ | ^
+ `-----'
+
+ The DATA indirection (which corresponds to `SCM_STRUCT_DATA ()') is necessary
+ to implement class redefinition.
+
+ For more details, see:
+
+ http://wingolog.org/archives/2009/11/09/class-redefinition-in-guile
+
+ */
+
+/* All vtables have the following fields. */
+#define SCM_VTABLE_BASE_LAYOUT \
+ "pr" /* layout */ \
+ "uh" /* flags */ \
+ "sr" /* self */ \
+ "uh" /* finalizer */ \
+ "pw" /* printer */ \
+ "ph" /* name (hidden from make-struct for back-compat reasons) */ \
+ "uh" /* size */ \
+ "uh" /* reserved */
+
+#define scm_vtable_index_layout 0 /* A symbol describing the physical arrangement of this type. */
+#define scm_vtable_index_flags 1 /* Class flags */
+#define scm_vtable_index_self 2 /* A pointer to the vtable itself */
+#define scm_vtable_index_instance_finalize 3 /* Finalizer for instances of this struct type. */
+#define scm_vtable_index_instance_printer 4 /* A printer for this struct type. */
+#define scm_vtable_index_name 5 /* Name of this vtable. */
+#define scm_vtable_index_size 6 /* Number of fields, for simple structs. */
+#define scm_vtable_index_reserved_7 7
+#define scm_vtable_offset_user 8 /* Where do user fields start in the vtable? */
+
+/* All applicable structs have the following fields. */
+#define SCM_APPLICABLE_BASE_LAYOUT \
+ "pw" /* procedure */
+#define SCM_APPLICABLE_WITH_SETTER_BASE_LAYOUT \
+ "pw" /* procedure */ \
+ "pw" /* setter */
+#define scm_applicable_struct_index_procedure 0 /* The procedure of an applicable
+ struct. Only valid if the
+ struct's vtable has the
+ applicable flag set. */
+#define scm_applicable_struct_index_setter 1 /* The setter of an applicable
+ struct. Only valid if the
+ struct's vtable has the
+ setter flag set. */
+
+#define SCM_VTABLE_FLAG_VALIDATED (1L << 0) /* the layout of this vtable been validated? */
+#define SCM_VTABLE_FLAG_VTABLE (1L << 1) /* instances of this vtable are themselves vtables? */
+#define SCM_VTABLE_FLAG_APPLICABLE_VTABLE (1L << 2) /* instances of this vtable are applicable vtables? */
+#define SCM_VTABLE_FLAG_APPLICABLE (1L << 3) /* instances of this vtable are applicable? */
+#define SCM_VTABLE_FLAG_SETTER_VTABLE (1L << 4) /* instances of this vtable are applicable-with-setter vtables? */
+#define SCM_VTABLE_FLAG_SETTER (1L << 5) /* instances of this vtable are applicable-with-setters? */
+#define SCM_VTABLE_FLAG_SIMPLE (1L << 6) /* instances of this vtable have only "p" fields and no tail array*/
+#define SCM_VTABLE_FLAG_SIMPLE_RW (1L << 7) /* instances of this vtable have only "pw" fields and no tail array */
+#define SCM_VTABLE_FLAG_RESERVED_0 (1L << 8)
+#define SCM_VTABLE_FLAG_RESERVED_1 (1L << 9)
+#define SCM_VTABLE_FLAG_RESERVED_2 (1L << 10)
+#define SCM_VTABLE_FLAG_SMOB_0 (1L << 11)
+#define SCM_VTABLE_FLAG_GOOPS_0 (1L << 12)
+#define SCM_VTABLE_FLAG_GOOPS_1 (1L << 13)
+#define SCM_VTABLE_FLAG_GOOPS_2 (1L << 14)
+#define SCM_VTABLE_FLAG_GOOPS_3 (1L << 15)
+#define SCM_VTABLE_USER_FLAG_SHIFT 16
+
+typedef void (*scm_t_struct_finalize) (SCM obj);
+
+#define SCM_STRUCTP(X) (!SCM_IMP(X) && (SCM_TYP3(X) == scm_tc3_struct))
+#define SCM_STRUCT_SLOTS(X) ((SCM*)SCM_CELL_WORD_1 ((X)))
+#define SCM_STRUCT_SLOT_REF(X,I) (SCM_STRUCT_SLOTS (X)[(I)])
+#define SCM_STRUCT_SLOT_SET(X,I,V) SCM_STRUCT_SLOTS (X)[(I)]=(V)
+#define SCM_STRUCT_DATA(X) ((scm_t_bits*)SCM_CELL_WORD_1 (X))
+#define SCM_STRUCT_DATA_REF(X,I) (SCM_STRUCT_DATA (X)[(I)])
+#define SCM_STRUCT_DATA_SET(X,I,V) SCM_STRUCT_DATA (X)[(I)]=(V)
+
+/* The SCM_VTABLE_* macros assume that you're passing them a struct which is a
+ valid vtable. */
+#define SCM_VTABLE_LAYOUT(X) (SCM_STRUCT_SLOT_REF ((X), scm_vtable_index_layout))
+#define SCM_SET_VTABLE_LAYOUT(X,L) (SCM_STRUCT_SLOT_SET ((X), scm_vtable_index_layout, L))
+#define SCM_VTABLE_FLAGS(X) (SCM_STRUCT_DATA_REF (X, scm_vtable_index_flags))
+#define SCM_SET_VTABLE_FLAGS(X,F) (SCM_STRUCT_DATA_REF (X, scm_vtable_index_flags) |= (F))
+#define SCM_CLEAR_VTABLE_FLAGS(X,F) (SCM_STRUCT_DATA_REF (X, scm_vtable_index_flags) &= (~(F)))
+#define SCM_VTABLE_FLAG_IS_SET(X,F) (SCM_STRUCT_DATA_REF (X, scm_vtable_index_flags) & (F))
+#define SCM_VTABLE_INSTANCE_FINALIZER(X) ((scm_t_struct_finalize)SCM_STRUCT_DATA_REF (X, scm_vtable_index_instance_finalize))
+#define SCM_SET_VTABLE_INSTANCE_FINALIZER(X,P) (SCM_STRUCT_DATA_SET (X, scm_vtable_index_instance_finalize, (scm_t_bits)(P)))
+#define SCM_VTABLE_INSTANCE_PRINTER(X) (SCM_STRUCT_SLOT_REF (X, scm_vtable_index_instance_printer))
+#define SCM_SET_VTABLE_INSTANCE_PRINTER(X,P) (SCM_STRUCT_SLOT_SET (X, scm_vtable_index_instance_printer, (P)))
+#define SCM_VTABLE_NAME(X) (SCM_STRUCT_SLOT_REF (X, scm_vtable_index_name))
+#define SCM_SET_VTABLE_NAME(X,V) (SCM_STRUCT_SLOT_SET (X, scm_vtable_index_name, V))
+
+/* Structs hold a pointer to their vtable's data, not the vtable itself. To get
+ the vtable we have to do an indirection through the self slot. */
+#define SCM_STRUCT_VTABLE_DATA(X) ((scm_t_bits*)(SCM_CELL_WORD_0 (X) - scm_tc3_struct))
+#define SCM_STRUCT_VTABLE_SLOTS(X) ((SCM*)(SCM_CELL_WORD_0 (X) - scm_tc3_struct))
+#define SCM_STRUCT_VTABLE(X) (SCM_STRUCT_VTABLE_SLOTS(X)[scm_vtable_index_self])
+/* But often we just need to access the vtable's data; we can do that without
+ the data->self->data indirection. */
+#define SCM_STRUCT_LAYOUT(X) (SCM_STRUCT_VTABLE_SLOTS (X)[scm_vtable_index_layout])
+#define SCM_STRUCT_PRINTER(X) (SCM_STRUCT_VTABLE_SLOTS (X)[scm_vtable_index_instance_printer])
+#define SCM_STRUCT_FINALIZER(X) ((scm_t_struct_finalize)SCM_STRUCT_VTABLE_DATA (X)[scm_vtable_index_instance_finalize])
+#define SCM_STRUCT_VTABLE_FLAGS(X) (SCM_STRUCT_VTABLE_DATA (X)[scm_vtable_index_flags])
+#define SCM_STRUCT_VTABLE_FLAG_IS_SET(X,F) (SCM_STRUCT_VTABLE_DATA (X)[scm_vtable_index_flags]&(F))
+
+#define SCM_STRUCT_APPLICABLE_P(X) (SCM_STRUCT_VTABLE_FLAG_IS_SET ((X), SCM_VTABLE_FLAG_APPLICABLE))
+#define SCM_STRUCT_SETTER_P(X) (SCM_STRUCT_VTABLE_FLAG_IS_SET ((X), SCM_VTABLE_FLAG_SETTER))
+#define SCM_STRUCT_PROCEDURE(X) (SCM_STRUCT_SLOT_REF (X, scm_applicable_struct_index_procedure))
+#define SCM_SET_STRUCT_PROCEDURE(X,P) (SCM_STRUCT_SLOT_SET (X, scm_applicable_struct_index_procedure, P))
+#define SCM_STRUCT_SETTER(X) (SCM_STRUCT_SLOT_REF (X, scm_applicable_struct_index_setter))
+#define SCM_SET_STRUCT_SETTER(X,P) (SCM_STRUCT_SLOT_SET (X, scm_applicable_struct_index_setter, P))
+
+SCM_API SCM scm_standard_vtable_vtable;
+SCM_API SCM scm_applicable_struct_vtable_vtable;
+SCM_API SCM scm_applicable_struct_with_setter_vtable_vtable;
+
+\f
+
+SCM_API SCM scm_make_struct_layout (SCM fields);
+SCM_API SCM scm_struct_p (SCM x);
+SCM_API SCM scm_struct_vtable_p (SCM x);
+SCM_API SCM scm_make_struct (SCM vtable, SCM tail_array_size, SCM init);
+SCM_API SCM scm_c_make_struct (SCM vtable, size_t n_tail, size_t n_inits,
+ scm_t_bits init, ...);
+SCM_API SCM scm_c_make_structv (SCM vtable, size_t n_tail, size_t n_inits,
+ scm_t_bits init[]);
+SCM_API SCM scm_make_vtable (SCM fields, SCM printer);
+SCM_INTERNAL SCM scm_i_make_vtable_vtable (SCM extra_fields);
+#if SCM_ENABLE_DEPRECATED == 1
+SCM_DEPRECATED SCM scm_make_vtable_vtable (SCM extra_fields, SCM tail_array_size, SCM init);
+#endif
+SCM_API SCM scm_struct_ref (SCM handle, SCM pos);
+SCM_API SCM scm_struct_set_x (SCM handle, SCM pos, SCM val);
+SCM_API SCM scm_struct_vtable (SCM handle);
+SCM_API SCM scm_struct_vtable_name (SCM vtable);
+SCM_API SCM scm_set_struct_vtable_name_x (SCM vtable, SCM name);
+SCM_API void scm_print_struct (SCM exp, SCM port, scm_print_state *);
+
+SCM_INTERNAL SCM scm_i_struct_equalp (SCM s1, SCM s2);
+SCM_INTERNAL unsigned long scm_struct_ihashq (SCM, unsigned long, void *);
+SCM_INTERNAL unsigned long scm_i_struct_hash (SCM s, unsigned long n,
+ size_t depth);
+SCM_INTERNAL SCM scm_i_alloc_struct (scm_t_bits *vtable_data, int n_words);
+SCM_INTERNAL void scm_i_struct_inherit_vtable_magic (SCM vtable, SCM obj);
+SCM_INTERNAL void scm_init_struct (void);
+
+#endif /* SCM_STRUCT_H */
+
+/*
+ Local Variables:
+ c-file-style: "gnu"
+ End:
+*/