1 /* Copyright (C) 1996,1997,1998,1999,2000,2001, 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.
3 * This library is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU Lesser General Public License
5 * as published by the Free Software Foundation; either version 3 of
6 * the License, or (at your option) any later version.
8 * This library is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * Lesser General Public License for more details.
13 * You should have received a copy of the GNU Lesser General Public
14 * License along with this library; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
27 #define SCM_BUILDING_DEPRECATED_CODE
29 #include "libguile/_scm.h"
30 #include "libguile/async.h"
31 #include "libguile/chars.h"
32 #include "libguile/eval.h"
33 #include "libguile/alist.h"
34 #include "libguile/hashtab.h"
35 #include "libguile/ports.h"
36 #include "libguile/strings.h"
37 #include "libguile/srfi-13.h"
39 #include "libguile/validate.h"
40 #include "libguile/struct.h"
42 #include "libguile/eq.h"
48 #include "libguile/bdw-gc.h"
52 /* A needlessly obscure test. */
53 #define SCM_LAYOUT_TAILP(X) (((X) & 32) == 0) /* R, W or O */
55 static SCM required_vtable_fields
= SCM_BOOL_F
;
56 static SCM required_applicable_fields
= SCM_BOOL_F
;
57 static SCM required_applicable_with_setter_fields
= SCM_BOOL_F
;
58 SCM scm_applicable_struct_vtable_vtable
;
59 SCM scm_applicable_struct_with_setter_vtable_vtable
;
60 SCM scm_standard_vtable_vtable
;
64 SCM_DEFINE (scm_make_struct_layout
, "make-struct-layout", 1, 0, 0,
66 "Return a new structure layout object.\n\n"
67 "@var{fields} must be a string made up of pairs of characters\n"
68 "strung together. The first character of each pair describes a field\n"
69 "type, the second a field protection. Allowed types are 'p' for\n"
70 "GC-protected Scheme data, 'u' for unprotected binary data, and 's' for\n"
71 "a field that points to the structure itself. Allowed protections\n"
72 "are 'w' for mutable fields, 'h' for hidden fields, 'r' for read-only\n"
73 "fields, and 'o' for opaque fields.\n\n"
74 "Hidden fields are writable, but they will not consume an initializer arg\n"
75 "passed to @code{make-struct}. They are useful to add slots to a struct\n"
76 "in a way that preserves backward-compatibility with existing calls to\n"
77 "@code{make-struct}, especially for derived vtables.\n\n"
78 "The last field protection specification may be capitalized to indicate\n"
79 "that the field is a tail-array.")
80 #define FUNC_NAME s_scm_make_struct_layout
85 SCM_VALIDATE_STRING (1, fields
);
91 len
= scm_i_string_length (fields
);
93 SCM_MISC_ERROR ("odd length field specification: ~S",
96 for (x
= 0; x
< len
; x
+= 2)
98 switch (c
= scm_i_string_ref (fields
, x
))
109 SCM_MISC_ERROR ("unrecognized field type: ~S",
110 scm_list_1 (SCM_MAKE_CHAR (c
)));
113 switch (c
= scm_i_string_ref (fields
, x
+ 1))
117 if (scm_i_string_ref (fields
, x
) == 's')
118 SCM_MISC_ERROR ("self fields not writable", SCM_EOL
);
125 if (scm_i_string_ref (fields
, x
) == 's')
126 SCM_MISC_ERROR ("self fields not allowed in tail array",
129 SCM_MISC_ERROR ("tail array field must be last field in layout",
133 SCM_MISC_ERROR ("unrecognized ref specification: ~S",
134 scm_list_1 (SCM_MAKE_CHAR (c
)));
137 if (scm_i_string_ref (fields
, x
, 'd'))
139 if (!scm_i_string_ref (fields
, x
+2, '-'))
140 SCM_MISC_ERROR ("missing dash field at position ~A",
141 scm_list_1 (scm_from_int (x
/ 2)));
147 new_sym
= scm_string_to_symbol (fields
);
149 scm_remember_upto_here_1 (fields
);
155 /* Check whether VTABLE instances have a simple layout (i.e., either only "pr"
156 or only "pw" fields) and update its flags accordingly. */
158 set_vtable_layout_flags (SCM vtable
)
162 const char *c_layout
;
163 scm_t_bits flags
= SCM_VTABLE_FLAG_SIMPLE
;
165 layout
= SCM_VTABLE_LAYOUT (vtable
);
166 c_layout
= scm_i_symbol_chars (layout
);
167 len
= scm_i_symbol_length (layout
);
169 assert (len
% 2 == 0);
171 /* Update FLAGS according to LAYOUT. */
173 field
< len
&& flags
& SCM_VTABLE_FLAG_SIMPLE
;
176 if (c_layout
[field
] != 'p')
179 switch (c_layout
[field
+ 1])
184 flags
|= SCM_VTABLE_FLAG_SIMPLE_RW
;
189 flags
&= ~SCM_VTABLE_FLAG_SIMPLE_RW
;
197 if (flags
& SCM_VTABLE_FLAG_SIMPLE
)
199 /* VTABLE is simple so update its flags and record the size of its
201 SCM_SET_VTABLE_FLAGS (vtable
, flags
);
202 SCM_STRUCT_DATA_SET (vtable
, scm_vtable_index_size
, len
/ 2);
207 scm_is_valid_vtable_layout (SCM layout
)
210 const char *c_layout
;
212 c_layout
= scm_i_symbol_chars (layout
);
213 len
= scm_i_symbol_length (layout
);
218 for (n
= 0; n
< len
; n
+= 2)
224 switch (c_layout
[n
+1])
246 /* Have OBJ, a newly created vtable, inherit flags from VTABLE. VTABLE is a
247 vtable-vtable and OBJ is an instance of VTABLE. */
249 scm_i_struct_inherit_vtable_magic (SCM vtable
, SCM obj
)
250 #define FUNC_NAME "%inherit-vtable-magic"
252 /* Verily, what is the deal here, you ask? Basically, we need to know a couple
253 of properties of structures at runtime. For example, "is this structure a
254 vtable of vtables (a metaclass)?"; also, "is this structure applicable?".
255 Both of these questions also imply a certain layout of the structure. So
256 instead of checking the layout at runtime, what we do is pre-verify the
257 layout -- so that at runtime we can just check the applicable flag and
258 dispatch directly to the Scheme procedure in slot 0. */
261 /* Verify that OBJ is a valid vtable. */
262 if (! scm_is_valid_vtable_layout (SCM_VTABLE_LAYOUT (obj
)))
263 SCM_MISC_ERROR ("invalid layout for new vtable: ~a",
264 scm_list_1 (SCM_VTABLE_LAYOUT (obj
)));
266 set_vtable_layout_flags (obj
);
268 /* If OBJ's vtable is compatible with the required vtable (class) layout, it
270 olayout
= scm_symbol_to_string (SCM_VTABLE_LAYOUT (obj
));
271 if (scm_is_true (scm_leq_p (scm_string_length (required_vtable_fields
),
272 scm_string_length (olayout
)))
273 && scm_is_true (scm_string_eq (olayout
, required_vtable_fields
,
275 scm_string_length (required_vtable_fields
),
277 scm_string_length (required_vtable_fields
))))
278 SCM_SET_VTABLE_FLAGS (obj
, SCM_VTABLE_FLAG_VTABLE
);
280 /* Finally, if OBJ is an applicable class, verify that its vtable is
281 compatible with the required applicable layout. */
282 if (SCM_VTABLE_FLAG_IS_SET (vtable
, SCM_VTABLE_FLAG_SETTER_VTABLE
))
284 if (scm_is_false (scm_string_eq (olayout
, required_applicable_with_setter_fields
,
288 scm_from_size_t (4))))
289 SCM_MISC_ERROR ("invalid applicable-with-setter struct layout",
290 scm_list_1 (olayout
));
291 SCM_SET_VTABLE_FLAGS (obj
, SCM_VTABLE_FLAG_APPLICABLE
| SCM_VTABLE_FLAG_SETTER
);
293 else if (SCM_VTABLE_FLAG_IS_SET (vtable
, SCM_VTABLE_FLAG_APPLICABLE_VTABLE
))
295 if (scm_is_false (scm_string_eq (olayout
, required_applicable_fields
,
299 scm_from_size_t (2))))
300 SCM_MISC_ERROR ("invalid applicable struct layout",
301 scm_list_1 (olayout
));
302 SCM_SET_VTABLE_FLAGS (obj
, SCM_VTABLE_FLAG_APPLICABLE
);
305 SCM_SET_VTABLE_FLAGS (obj
, SCM_VTABLE_FLAG_VALIDATED
);
311 scm_struct_init (SCM handle
, SCM layout
, size_t n_tail
,
312 size_t n_inits
, scm_t_bits
*inits
)
317 vtable
= SCM_STRUCT_VTABLE (handle
);
318 mem
= SCM_STRUCT_DATA (handle
);
320 if (SCM_UNPACK (vtable
) != 0
321 && SCM_VTABLE_FLAG_IS_SET (vtable
, SCM_VTABLE_FLAG_SIMPLE
)
323 && n_inits
== SCM_STRUCT_DATA_REF (vtable
, scm_vtable_index_size
))
324 /* The fast path: HANDLE has N_INITS "p" fields. */
325 memcpy (mem
, inits
, n_inits
* sizeof (SCM
));
328 scm_t_wchar prot
= 0;
329 int n_fields
= scm_i_symbol_length (layout
) / 2;
332 size_t inits_idx
= 0;
340 prot
= scm_i_symbol_ref (layout
, i
+1);
341 if (SCM_LAYOUT_TAILP (prot
))
344 prot
= prot
== 'R' ? 'r' : prot
== 'W' ? 'w' : 'o';
345 *mem
++ = (scm_t_bits
)n_tail
;
346 n_fields
+= n_tail
- 1;
351 switch (scm_i_symbol_ref (layout
, i
))
354 if ((prot
!= 'r' && prot
!= 'w') || inits_idx
== n_inits
)
358 *mem
= scm_to_ulong (SCM_PACK (inits
[inits_idx
]));
364 if ((prot
!= 'r' && prot
!= 'w') || inits_idx
== n_inits
)
365 *mem
= SCM_UNPACK (SCM_BOOL_F
);
368 *mem
= inits
[inits_idx
];
375 *mem
= SCM_UNPACK (handle
);
386 SCM_DEFINE (scm_struct_p
, "struct?", 1, 0, 0,
388 "Return @code{#t} iff @var{x} is a structure object, else\n"
390 #define FUNC_NAME s_scm_struct_p
392 return scm_from_bool(SCM_STRUCTP (x
));
396 SCM_DEFINE (scm_struct_vtable_p
, "struct-vtable?", 1, 0, 0,
398 "Return @code{#t} iff @var{x} is a vtable structure.")
399 #define FUNC_NAME s_scm_struct_vtable_p
402 || !SCM_STRUCT_VTABLE_FLAG_IS_SET (x
, SCM_VTABLE_FLAG_VTABLE
))
404 if (!SCM_VTABLE_FLAG_IS_SET (x
, SCM_VTABLE_FLAG_VALIDATED
))
405 SCM_MISC_ERROR ("vtable has invalid layout: ~A",
406 scm_list_1 (SCM_VTABLE_LAYOUT (x
)));
412 /* Finalization: invoke the finalizer of the struct pointed to by PTR. */
414 struct_finalizer_trampoline (void *ptr
, void *unused_data
)
416 SCM obj
= PTR2SCM (ptr
);
417 scm_t_struct_finalize finalize
= SCM_STRUCT_FINALIZER (obj
);
423 /* All struct data must be allocated at an address whose bottom three
424 bits are zero. This is because the tag for a struct lives in the
425 bottom three bits of the struct's car, and the upper bits point to
426 the data of its vtable, which is a struct itself. Thus, if the
427 address of that data doesn't end in three zeros, tagging it will
430 I suppose we should make it clear here that, the data must be 8-byte aligned,
431 *within* the struct, and the struct itself should be 8-byte aligned. In
432 practice we ensure this because the data starts two words into a struct.
434 This function allocates an 8-byte aligned block of memory, whose first word
435 points to the given vtable data, then a data pointer, then n_words of data.
438 scm_i_alloc_struct (scm_t_bits
*vtable_data
, int n_words
)
442 ret
= scm_words ((scm_t_bits
)vtable_data
| scm_tc3_struct
, n_words
+ 2);
443 SCM_SET_CELL_WORD_1 (ret
, (scm_t_bits
)SCM_CELL_OBJECT_LOC (ret
, 2));
445 /* vtable_data can be null when making a vtable vtable */
446 if (vtable_data
&& vtable_data
[scm_vtable_index_instance_finalize
])
447 /* Register a finalizer for the newly created instance. */
448 scm_i_set_finalizer (SCM2PTR (ret
), struct_finalizer_trampoline
, NULL
);
455 scm_c_make_structv (SCM vtable
, size_t n_tail
, size_t n_init
, scm_t_bits
*init
)
456 #define FUNC_NAME "make-struct"
462 SCM_VALIDATE_VTABLE (1, vtable
);
464 layout
= SCM_VTABLE_LAYOUT (vtable
);
465 basic_size
= scm_i_symbol_length (layout
) / 2;
469 SCM layout_str
, last_char
;
474 SCM_MISC_ERROR ("tail array not allowed unless layout ends R, W, or O", SCM_EOL
);
477 layout_str
= scm_symbol_to_string (layout
);
478 last_char
= scm_string_ref (layout_str
,
479 scm_from_size_t (2 * basic_size
- 1));
480 if (! SCM_LAYOUT_TAILP (SCM_CHAR (last_char
)))
484 obj
= scm_i_alloc_struct (SCM_STRUCT_DATA (vtable
), basic_size
+ n_tail
);
486 scm_struct_init (obj
, layout
, n_tail
, n_init
, init
);
488 /* If we're making a vtable, validate its layout and inherit
489 flags. However we allow for separation of allocation and
490 initialization, to humor GOOPS, so only validate if the layout was
491 passed as an initarg. */
492 if (SCM_VTABLE_FLAG_IS_SET (vtable
, SCM_VTABLE_FLAG_VTABLE
)
493 && scm_is_true (SCM_VTABLE_LAYOUT (obj
)))
494 scm_i_struct_inherit_vtable_magic (vtable
, obj
);
501 scm_c_make_struct (SCM vtable
, size_t n_tail
, size_t n_init
, scm_t_bits init
, ...)
507 v
= alloca (sizeof (scm_t_bits
) * n_init
);
509 va_start (foo
, init
);
510 for (i
= 0; i
< n_init
; i
++)
513 init
= va_arg (foo
, scm_t_bits
);
517 return scm_c_make_structv (vtable
, n_tail
, n_init
, v
);
520 SCM_DEFINE (scm_make_struct
, "make-struct", 2, 0, 1,
521 (SCM vtable
, SCM tail_array_size
, SCM init
),
522 "Create a new structure.\n\n"
523 "@var{vtable} must be a vtable structure (@pxref{Vtables}).\n\n"
524 "@var{tail_array_size} must be a non-negative integer. If the layout\n"
525 "specification indicated by @var{vtable} includes a tail-array,\n"
526 "this is the number of elements allocated to that array.\n\n"
527 "The @var{init1}, @dots{} are optional arguments describing how\n"
528 "successive fields of the structure should be initialized. Only fields\n"
529 "with protection 'r' or 'w' can be initialized, except for fields of\n"
530 "type 's', which are automatically initialized to point to the new\n"
531 "structure itself. Fields with protection 'o' can not be initialized by\n"
532 "Scheme programs.\n\n"
533 "If fewer optional arguments than initializable fields are supplied,\n"
534 "fields of type 'p' get default value #f while fields of type 'u' are\n"
536 #define FUNC_NAME s_scm_make_struct
542 SCM_VALIDATE_VTABLE (1, vtable
);
543 ilen
= scm_ilength (init
);
545 SCM_MISC_ERROR ("Rest arguments do not form a proper list.", SCM_EOL
);
547 n_init
= (size_t)ilen
;
549 /* best to use alloca, but init could be big, so hack to avoid a possible
552 v
= alloca (n_init
* sizeof(scm_t_bits
));
554 v
= scm_gc_malloc (n_init
* sizeof(scm_t_bits
), "struct");
556 for (i
= 0; i
< n_init
; i
++, init
= SCM_CDR (init
))
557 v
[i
] = SCM_UNPACK (SCM_CAR (init
));
559 return scm_c_make_structv (vtable
, scm_to_size_t (tail_array_size
), n_init
, v
);
564 scm_i_make_vtable_vtable (SCM user_fields
)
565 #define FUNC_NAME "make-vtable-vtable"
567 SCM fields
, layout
, obj
;
571 SCM_VALIDATE_STRING (1, user_fields
);
573 fields
= scm_string_append (scm_list_2 (required_vtable_fields
,
575 layout
= scm_make_struct_layout (fields
);
576 if (!scm_is_valid_vtable_layout (layout
))
577 SCM_MISC_ERROR ("invalid user fields", scm_list_1 (user_fields
));
579 basic_size
= scm_i_symbol_length (layout
) / 2;
581 obj
= scm_i_alloc_struct (NULL
, basic_size
);
582 /* Make it so that the vtable of OBJ is itself. */
583 SCM_SET_CELL_WORD_0 (obj
, (scm_t_bits
) SCM_STRUCT_DATA (obj
) | scm_tc3_struct
);
585 v
= SCM_UNPACK (layout
);
586 scm_struct_init (obj
, layout
, 0, 1, &v
);
587 SCM_SET_VTABLE_FLAGS (obj
,
588 SCM_VTABLE_FLAG_VTABLE
| SCM_VTABLE_FLAG_VALIDATED
);
594 SCM_DEFINE (scm_make_vtable
, "make-vtable", 1, 1, 0,
595 (SCM fields
, SCM printer
),
596 "Create a vtable, for creating structures with the given\n"
599 "The optional @var{printer} argument is a function to be called\n"
600 "@code{(@var{printer} struct port)} on the structures created.\n"
601 "It should look at @var{struct} and write to @var{port}.")
602 #define FUNC_NAME s_scm_make_vtable
604 if (SCM_UNBNDP (printer
))
605 printer
= SCM_BOOL_F
;
607 return scm_make_struct (scm_standard_vtable_vtable
, SCM_INUM0
,
608 scm_list_2 (scm_make_struct_layout (fields
),
614 /* Return true if S1 and S2 are equal structures, i.e., if their vtable and
615 contents are the same. Field protections are honored. Thus, it is an
616 error to test the equality of structures that contain opaque fields. */
618 scm_i_struct_equalp (SCM s1
, SCM s2
)
619 #define FUNC_NAME "scm_i_struct_equalp"
621 SCM vtable1
, vtable2
, layout
;
622 size_t struct_size
, field_num
;
624 SCM_VALIDATE_STRUCT (1, s1
);
625 SCM_VALIDATE_STRUCT (2, s2
);
627 vtable1
= SCM_STRUCT_VTABLE (s1
);
628 vtable2
= SCM_STRUCT_VTABLE (s2
);
630 if (!scm_is_eq (vtable1
, vtable2
))
633 layout
= SCM_STRUCT_LAYOUT (s1
);
634 struct_size
= scm_i_symbol_length (layout
) / 2;
636 for (field_num
= 0; field_num
< struct_size
; field_num
++)
641 /* We have to use `scm_struct_ref ()' here so that fields are accessed
642 consistently, notably wrt. field types and access rights. */
643 s_field_num
= scm_from_size_t (field_num
);
644 field1
= scm_struct_ref (s1
, s_field_num
);
645 field2
= scm_struct_ref (s2
, s_field_num
);
647 /* Self-referencing fields (type `s') must be skipped to avoid infinite
649 if (!(scm_is_eq (field1
, s1
) && (scm_is_eq (field2
, s2
))))
650 if (scm_is_false (scm_equal_p (field1
, field2
)))
654 /* FIXME: Tail elements should be tested for equality. */
664 SCM_DEFINE (scm_struct_ref
, "struct-ref", 2, 0, 0,
665 (SCM handle
, SCM pos
),
666 "Access the @var{pos}th field of struct associated with\n"
669 "If the field is of type 'p', then it can be set to an arbitrary\n"
672 "If the field is of type 'u', then it can only be set to a\n"
673 "non-negative integer value small enough to fit in one machine\n"
675 #define FUNC_NAME s_scm_struct_ref
677 SCM vtable
, answer
= SCM_UNDEFINED
;
681 SCM_VALIDATE_STRUCT (1, handle
);
683 vtable
= SCM_STRUCT_VTABLE (handle
);
684 data
= SCM_STRUCT_DATA (handle
);
685 p
= scm_to_size_t (pos
);
687 if (SCM_LIKELY (SCM_VTABLE_FLAG_IS_SET (vtable
, SCM_VTABLE_FLAG_SIMPLE
)
688 && p
< SCM_STRUCT_DATA_REF (vtable
, scm_vtable_index_size
)))
689 /* The fast path: HANDLE is a struct with only "p" fields. */
690 answer
= SCM_PACK (data
[p
]);
694 size_t layout_len
, n_fields
;
695 scm_t_wchar field_type
= 0;
697 layout
= SCM_STRUCT_LAYOUT (handle
);
698 layout_len
= scm_i_symbol_length (layout
);
699 n_fields
= layout_len
/ 2;
701 if (SCM_LAYOUT_TAILP (scm_i_symbol_ref (layout
, layout_len
- 1)))
702 n_fields
+= data
[n_fields
- 1];
704 SCM_ASSERT_RANGE (1, pos
, p
< n_fields
);
706 if (p
* 2 < layout_len
)
709 field_type
= scm_i_symbol_ref (layout
, p
* 2);
710 ref
= scm_i_symbol_ref (layout
, p
* 2 + 1);
711 if ((ref
!= 'r') && (ref
!= 'w') && (ref
!= 'h'))
713 if ((ref
== 'R') || (ref
== 'W'))
716 SCM_MISC_ERROR ("ref denied for field ~A", scm_list_1 (pos
));
719 else if (scm_i_symbol_ref (layout
, layout_len
- 1) != 'O')
720 field_type
= scm_i_symbol_ref(layout
, layout_len
- 2);
722 SCM_MISC_ERROR ("ref denied for field ~A", scm_list_1 (pos
));
727 answer
= scm_from_ulong (data
[p
]);
732 answer
= scm_from_long (data
[p
]);
736 answer
= scm_make_real (*((double *)&(data
[p
])));
742 answer
= SCM_PACK (data
[p
]);
747 SCM_MISC_ERROR ("unrecognized field type: ~S",
748 scm_list_1 (SCM_MAKE_CHAR (field_type
)));
757 SCM_DEFINE (scm_struct_set_x
, "struct-set!", 3, 0, 0,
758 (SCM handle
, SCM pos
, SCM val
),
759 "Set the slot of the structure @var{handle} with index @var{pos}\n"
760 "to @var{val}. Signal an error if the slot can not be written\n"
762 #define FUNC_NAME s_scm_struct_set_x
768 SCM_VALIDATE_STRUCT (1, handle
);
770 vtable
= SCM_STRUCT_VTABLE (handle
);
771 data
= SCM_STRUCT_DATA (handle
);
772 p
= scm_to_size_t (pos
);
774 if (SCM_LIKELY (SCM_VTABLE_FLAG_IS_SET (vtable
, SCM_VTABLE_FLAG_SIMPLE
)
775 && SCM_VTABLE_FLAG_IS_SET (vtable
, SCM_VTABLE_FLAG_SIMPLE_RW
)
776 && p
< SCM_STRUCT_DATA_REF (vtable
, scm_vtable_index_size
)))
777 /* The fast path: HANDLE is a struct with only "pw" fields. */
778 data
[p
] = SCM_UNPACK (val
);
782 size_t layout_len
, n_fields
;
783 scm_t_wchar field_type
= 0;
785 layout
= SCM_STRUCT_LAYOUT (handle
);
786 layout_len
= scm_i_symbol_length (layout
);
787 n_fields
= layout_len
/ 2;
789 if (SCM_LAYOUT_TAILP (scm_i_symbol_ref (layout
, layout_len
- 1)))
790 n_fields
+= data
[n_fields
- 1];
792 SCM_ASSERT_RANGE (1, pos
, p
< n_fields
);
794 if (p
* 2 < layout_len
)
797 field_type
= scm_i_symbol_ref (layout
, p
* 2);
798 set_x
= scm_i_symbol_ref (layout
, p
* 2 + 1);
799 if (set_x
!= 'w' && set_x
!= 'h')
800 SCM_MISC_ERROR ("set! denied for field ~A", scm_list_1 (pos
));
802 else if (scm_i_symbol_ref (layout
, layout_len
- 1) == 'W')
803 field_type
= scm_i_symbol_ref (layout
, layout_len
- 2);
805 SCM_MISC_ERROR ("set! denied for field ~A", scm_list_1 (pos
));
810 data
[p
] = SCM_NUM2ULONG (3, val
);
815 data
[p
] = SCM_NUM2LONG (3, val
);
819 *((double *)&(data
[p
])) = scm_num2dbl (val
, (char *)SCM_ARG3
);
824 data
[p
] = SCM_UNPACK (val
);
828 SCM_MISC_ERROR ("self fields immutable", SCM_EOL
);
831 SCM_MISC_ERROR ("unrecognized field type: ~S",
832 scm_list_1 (SCM_MAKE_CHAR (field_type
)));
841 SCM_DEFINE (scm_struct_vtable
, "struct-vtable", 1, 0, 0,
843 "Return the vtable structure that describes the type of struct\n"
844 "associated with @var{handle}.")
845 #define FUNC_NAME s_scm_struct_vtable
847 SCM_VALIDATE_STRUCT (1, handle
);
848 return SCM_STRUCT_VTABLE (handle
);
853 /* {Associating names and classes with vtables}
855 * The name of a vtable should probably be stored as a slot. This is
856 * a backward compatible solution until agreement has been achieved on
857 * how to associate names with vtables.
861 scm_struct_ihashq (SCM obj
, unsigned long n
, void *closure
)
863 /* The length of the hash table should be a relative prime it's not
864 necessary to shift down the address. */
865 return SCM_UNPACK (obj
) % n
;
868 SCM_DEFINE (scm_struct_vtable_name
, "struct-vtable-name", 1, 0, 0,
870 "Return the name of the vtable @var{vtable}.")
871 #define FUNC_NAME s_scm_struct_vtable_name
873 SCM_VALIDATE_VTABLE (1, vtable
);
874 return SCM_VTABLE_NAME (vtable
);
878 SCM_DEFINE (scm_set_struct_vtable_name_x
, "set-struct-vtable-name!", 2, 0, 0,
879 (SCM vtable
, SCM name
),
880 "Set the name of the vtable @var{vtable} to @var{name}.")
881 #define FUNC_NAME s_scm_set_struct_vtable_name_x
883 SCM_VALIDATE_VTABLE (1, vtable
);
884 SCM_VALIDATE_SYMBOL (2, name
);
885 SCM_SET_VTABLE_NAME (vtable
, name
);
886 /* FIXME: remove this, and implement proper struct classes instead.
887 (Vtables *are* classes.) */
888 scm_i_define_class_for_vtable (vtable
);
889 return SCM_UNSPECIFIED
;
897 scm_print_struct (SCM exp
, SCM port
, scm_print_state
*pstate
)
899 if (scm_is_true (scm_procedure_p (SCM_STRUCT_PRINTER (exp
))))
900 scm_printer_apply (SCM_STRUCT_PRINTER (exp
), exp
, port
, pstate
);
903 SCM vtable
= SCM_STRUCT_VTABLE (exp
);
904 SCM name
= scm_struct_vtable_name (vtable
);
905 scm_puts_unlocked ("#<", port
);
906 if (scm_is_true (name
))
908 scm_display (name
, port
);
909 scm_putc_unlocked (' ', port
);
913 if (SCM_VTABLE_FLAG_IS_SET (vtable
, SCM_VTABLE_FLAG_VTABLE
))
914 scm_puts_unlocked ("vtable:", port
);
916 scm_puts_unlocked ("struct:", port
);
917 scm_uintprint (SCM_UNPACK (vtable
), 16, port
);
918 scm_putc_unlocked (' ', port
);
919 scm_write (SCM_VTABLE_LAYOUT (vtable
), port
);
920 scm_putc_unlocked (' ', port
);
922 scm_uintprint (SCM_UNPACK (exp
), 16, port
);
924 if (SCM_STRUCT_APPLICABLE_P (exp
))
926 if (scm_is_true (SCM_STRUCT_PROCEDURE (exp
)))
928 scm_puts_unlocked (" proc: ", port
);
929 if (scm_is_true (scm_procedure_p (SCM_STRUCT_PROCEDURE (exp
))))
930 scm_write (SCM_STRUCT_PROCEDURE (exp
), port
);
932 scm_puts_unlocked ("(not a procedure?)", port
);
934 if (SCM_STRUCT_SETTER_P (exp
))
936 scm_puts_unlocked (" setter: ", port
);
937 scm_write (SCM_STRUCT_SETTER (exp
), port
);
940 scm_putc_unlocked ('>', port
);
949 /* The first word of a struct is equal to `SCM_STRUCT_DATA (vtable) +
950 scm_tc3_struct', and `SCM_STRUCT_DATA (vtable)' is 2 words after VTABLE by
952 GC_REGISTER_DISPLACEMENT (2 * sizeof (scm_t_bits
) + scm_tc3_struct
);
954 /* In the general case, `SCM_STRUCT_DATA (obj)' points 2 words after the
955 beginning of a GC-allocated region; that region is different from that of
956 OBJ once OBJ has undergone class redefinition. */
957 GC_REGISTER_DISPLACEMENT (2 * sizeof (scm_t_bits
));
959 required_vtable_fields
= scm_from_locale_string (SCM_VTABLE_BASE_LAYOUT
);
960 scm_c_define ("standard-vtable-fields", required_vtable_fields
);
961 required_applicable_fields
= scm_from_locale_string (SCM_APPLICABLE_BASE_LAYOUT
);
962 required_applicable_with_setter_fields
= scm_from_locale_string (SCM_APPLICABLE_WITH_SETTER_BASE_LAYOUT
);
964 scm_standard_vtable_vtable
= scm_i_make_vtable_vtable (scm_nullstr
);
965 name
= scm_from_utf8_symbol ("<standard-vtable>");
966 scm_set_struct_vtable_name_x (scm_standard_vtable_vtable
, name
);
967 scm_define (name
, scm_standard_vtable_vtable
);
969 scm_applicable_struct_vtable_vtable
=
970 scm_make_struct (scm_standard_vtable_vtable
, SCM_INUM0
,
971 scm_list_1 (scm_make_struct_layout (required_vtable_fields
)));
972 name
= scm_from_utf8_symbol ("<applicable-struct-vtable>");
973 SCM_SET_VTABLE_FLAGS (scm_applicable_struct_vtable_vtable
,
974 SCM_VTABLE_FLAG_APPLICABLE_VTABLE
);
975 scm_set_struct_vtable_name_x (scm_applicable_struct_vtable_vtable
, name
);
976 scm_define (name
, scm_applicable_struct_vtable_vtable
);
978 scm_applicable_struct_with_setter_vtable_vtable
=
979 scm_make_struct (scm_standard_vtable_vtable
, SCM_INUM0
,
980 scm_list_1 (scm_make_struct_layout (required_vtable_fields
)));
981 name
= scm_from_utf8_symbol ("<applicable-struct-with-setter-vtable>");
982 scm_set_struct_vtable_name_x (scm_applicable_struct_with_setter_vtable_vtable
, name
);
983 SCM_SET_VTABLE_FLAGS (scm_applicable_struct_with_setter_vtable_vtable
,
984 SCM_VTABLE_FLAG_APPLICABLE_VTABLE
| SCM_VTABLE_FLAG_SETTER_VTABLE
);
985 scm_define (name
, scm_applicable_struct_with_setter_vtable_vtable
);
987 scm_c_define ("vtable-index-layout", scm_from_int (scm_vtable_index_layout
));
988 scm_c_define ("vtable-index-printer",
989 scm_from_int (scm_vtable_index_instance_printer
));
990 scm_c_define ("vtable-offset-user", scm_from_int (scm_vtable_offset_user
));
991 #include "libguile/struct.x"