1 /* The "lrecord" structure (header of a compound lisp object).
2 Copyright (C) 1993, 1994, 1995 Free Software Foundation, Inc.
3 Copyright (C) 1996 Ben Wing.
5 This file is part of XEmacs.
7 XEmacs is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by the
9 Free Software Foundation; either version 2, or (at your option) any
12 XEmacs is distributed in the hope that it will be useful, but WITHOUT
13 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with XEmacs; see the file COPYING. If not, write to
19 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
22 /* Synched up with: Not in FSF. */
24 #ifndef INCLUDED_lrecord_h_
25 #define INCLUDED_lrecord_h_
27 /* The "lrecord" type of Lisp object is used for all object types
28 other than a few simple ones. This allows many types to be
29 implemented but only a few bits required in a Lisp object for type
30 information. (The tradeoff is that each object has its type marked
31 in it, thereby increasing its size.) All lrecords begin with a
32 `struct lrecord_header', which identifies the lisp object type, by
33 providing an index into a table of `struct lrecord_implementation',
34 which describes the behavior of the lisp object. It also contains
37 Lrecords are of two types: straight lrecords, and lcrecords.
38 Straight lrecords are used for those types of objects that have
39 their own allocation routines (typically allocated out of 2K chunks
40 of memory called `frob blocks'). These objects have a `struct
41 lrecord_header' at the top, containing only the bits needed to find
42 the lrecord_implementation for the object. There are special
43 routines in alloc.c to deal with each such object type.
45 Lcrecords are used for less common sorts of objects that don't do
46 their own allocation. Each such object is malloc()ed individually,
47 and the objects are chained together through a `next' pointer.
48 Lcrecords have a `struct lcrecord_header' at the top, which
49 contains a `struct lrecord_header' and a `next' pointer, and are
50 allocated using alloc_lcrecord().
52 Creating a new lcrecord type is fairly easy; just follow the
53 lead of some existing type (e.g. hash tables). Note that you
54 do not need to supply all the methods (see below); reasonable
55 defaults are provided for many of them. Alternatively, if you're
56 just looking for a way of encapsulating data (which possibly
57 could contain Lisp_Objects in it), you may well be able to use
62 /* index into lrecord_implementations_table[] */
65 /* If `mark' is 0 after the GC mark phase, the object will be freed
66 during the GC sweep phase. There are 2 ways that `mark' can be 1:
67 - by being referenced from other objects during the GC mark phase
68 - because it is permanently on, for c_readonly objects */
71 /* 1 if the object resides in logically read-only space, and does not
72 reference other non-c_readonly objects.
73 Invariant: if (c_readonly == 1), then (mark == 1 && lisp_readonly == 1) */
74 unsigned int c_readonly :1;
76 /* 1 if the object is readonly from lisp */
77 unsigned int lisp_readonly :1;
80 /* The `older field is a flag that indicates whether this lcrecord
81 is on a "older storage". */
82 unsigned int older :1;
86 struct lrecord_implementation;
87 int lrecord_type_index (const struct lrecord_implementation *implementation);
90 #define set_lheader_implementation(header,imp) do { \
91 struct lrecord_header* SLI_header = (header); \
92 SLI_header->type = (imp)->lrecord_type_index; \
93 SLI_header->mark = 0; \
94 SLI_header->older = 0; \
95 SLI_header->c_readonly = 0; \
96 SLI_header->lisp_readonly = 0; \
98 #define set_lheader_older_implementation(header,imp) do { \
99 struct lrecord_header* SLI_header = (header); \
100 SLI_header->type = (imp)->lrecord_type_index; \
101 SLI_header->mark = 0; \
102 SLI_header->older = 1; \
103 SLI_header->c_readonly = 0; \
104 SLI_header->lisp_readonly = 0; \
107 #define set_lheader_implementation(header,imp) do { \
108 struct lrecord_header* SLI_header = (header); \
109 SLI_header->type = (imp)->lrecord_type_index; \
110 SLI_header->mark = 0; \
111 SLI_header->c_readonly = 0; \
112 SLI_header->lisp_readonly = 0; \
116 struct lcrecord_header
118 struct lrecord_header lheader;
120 /* The `next' field is normally used to chain all lcrecords together
121 so that the GC can find (and free) all of them.
122 `alloc_lcrecord' threads lcrecords together.
124 The `next' field may be used for other purposes as long as some
125 other mechanism is provided for letting the GC do its work.
127 For example, the event and marker object types allocate members
128 out of memory chunks, and are able to find all unmarked members
129 by sweeping through the elements of the list of chunks. */
130 struct lcrecord_header *next;
132 /* The `uid' field is just for debugging/printing convenience.
133 Having this slot doesn't hurt us much spacewise, since an
134 lcrecord already has the above slots plus malloc overhead. */
135 unsigned int uid :31;
137 /* The `free' field is a flag that indicates whether this lcrecord
138 is on a "free list". Free lists are used to minimize the number
139 of calls to malloc() when we're repeatedly allocating and freeing
140 a number of the same sort of lcrecord. Lcrecords on a free list
141 always get marked in a different fashion, so we can use this flag
142 as a sanity check to make sure that free lists only have freed
143 lcrecords and there are no freed lcrecords elsewhere. */
144 unsigned int free :1;
147 /* Used for lcrecords in an lcrecord-list. */
148 struct free_lcrecord_header
150 struct lcrecord_header lcheader;
156 /* Symbol value magic types come first to make SYMBOL_VALUE_MAGIC_P fast.
157 #### This should be replaced by a symbol_value_magic_p flag
158 in the Lisp_Symbol lrecord_header. */
159 lrecord_type_symbol_value_forward,
160 lrecord_type_symbol_value_varalias,
161 lrecord_type_symbol_value_lisp_magic,
162 lrecord_type_symbol_value_buffer_local,
163 lrecord_type_max_symbol_value_magic = lrecord_type_symbol_value_buffer_local,
170 lrecord_type_lcrecord_list,
171 lrecord_type_compiled_function,
172 lrecord_type_weak_list,
173 lrecord_type_bit_vector,
175 lrecord_type_hash_table,
176 lrecord_type_lstream,
177 lrecord_type_process,
178 lrecord_type_charset,
179 lrecord_type_coding_system,
180 lrecord_type_char_table,
181 lrecord_type_char_table_entry,
182 lrecord_type_char_id_table,
183 lrecord_type_byte_table,
184 lrecord_type_uint16_byte_table,
185 lrecord_type_uint8_byte_table,
186 lrecord_type_range_table,
188 lrecord_type_opaque_ptr,
191 lrecord_type_extent_info,
192 lrecord_type_extent_auxiliary,
196 lrecord_type_command_builder,
197 lrecord_type_timeout,
198 lrecord_type_specifier,
199 lrecord_type_console,
203 lrecord_type_window_configuration,
204 lrecord_type_gui_item,
205 lrecord_type_popup_data,
206 lrecord_type_toolbar_button,
207 lrecord_type_color_instance,
208 lrecord_type_font_instance,
209 lrecord_type_image_instance,
212 lrecord_type_database,
213 lrecord_type_tooltalk_message,
214 lrecord_type_tooltalk_pattern,
217 lrecord_type_pgresult,
218 lrecord_type_devmode,
219 lrecord_type_count /* must be last */
222 struct lrecord_implementation
226 /* `marker' is called at GC time, to make sure that all Lisp_Objects
227 pointed to by this object get properly marked. It should call
228 the mark_object function on all Lisp_Objects in the object. If
229 the return value is non-nil, it should be a Lisp_Object to be
230 marked (don't call the mark_object function explicitly on it,
231 because the GC routines will do this). Doing it this way reduces
232 recursion, so the object returned should preferably be the one
233 with the deepest level of Lisp_Object pointers. This function
234 can be NULL, meaning no GC marking is necessary. */
235 Lisp_Object (*marker) (Lisp_Object);
237 /* `printer' converts the object to a printed representation.
238 This can be NULL; in this case default_object_printer() will be
240 void (*printer) (Lisp_Object, Lisp_Object printcharfun, int escapeflag);
242 /* `finalizer' is called at GC time when the object is about to
243 be freed, and at dump time (FOR_DISKSAVE will be non-zero in this
244 case). It should perform any necessary cleanup (e.g. freeing
245 malloc()ed memory). This can be NULL, meaning no special
246 finalization is necessary.
248 WARNING: remember that `finalizer' is called at dump time even
249 though the object is not being freed. */
250 void (*finalizer) (void *header, int for_disksave);
252 /* This can be NULL, meaning compare objects with EQ(). */
253 int (*equal) (Lisp_Object obj1, Lisp_Object obj2, int depth);
255 /* `hash' generates hash values for use with hash tables that have
256 `equal' as their test function. This can be NULL, meaning use
257 the Lisp_Object itself as the hash. But, you must still satisfy
258 the constraint that if two objects are `equal', then they *must*
259 hash to the same value in order for hash tables to work properly.
260 This means that `hash' can be NULL only if the `equal' method is
262 unsigned long (*hash) (Lisp_Object, int);
264 /* External data layout description */
265 const struct lrecord_description *description;
267 /* These functions allow any object type to have builtin property
268 lists that can be manipulated from the lisp level with
269 `get', `put', `remprop', and `object-plist'. */
270 Lisp_Object (*getprop) (Lisp_Object obj, Lisp_Object prop);
271 int (*putprop) (Lisp_Object obj, Lisp_Object prop, Lisp_Object val);
272 int (*remprop) (Lisp_Object obj, Lisp_Object prop);
273 Lisp_Object (*plist) (Lisp_Object obj);
275 /* Only one of `static_size' and `size_in_bytes_method' is non-0.
276 If both are 0, this type is not instantiable by alloc_lcrecord(). */
278 size_t (*size_in_bytes_method) (const void *header);
280 /* The (constant) index into lrecord_implementations_table */
281 enum lrecord_type lrecord_type_index;
283 /* A "basic" lrecord is any lrecord that's not an lcrecord, i.e.
284 one that does not have an lcrecord_header at the front and which
285 is (usually) allocated in frob blocks. We only use this flag for
286 some consistency checking, and that only when error-checking is
288 unsigned int basic_p :1;
291 extern const struct lrecord_implementation *lrecord_implementations_table[];
293 #define XRECORD_LHEADER_IMPLEMENTATION(obj) \
294 LHEADER_IMPLEMENTATION (XRECORD_LHEADER (obj))
295 #define LHEADER_IMPLEMENTATION(lh) lrecord_implementations_table[(lh)->type]
297 extern int gc_in_progress;
299 #define MARKED_RECORD_P(obj) (XRECORD_LHEADER (obj)->mark)
300 #define MARKED_RECORD_HEADER_P(lheader) ((lheader)->mark)
301 #define MARK_RECORD_HEADER(lheader) ((void) ((lheader)->mark = 1))
302 #define UNMARK_RECORD_HEADER(lheader) ((void) ((lheader)->mark = 0))
304 #define OLDER_RECORD_P(obj) (XRECORD_LHEADER (obj)->older)
305 #define OLDER_RECORD_HEADER_P(lheader) ((lheader)->older)
308 #define C_READONLY_RECORD_HEADER_P(lheader) ((lheader)->c_readonly)
309 #define LISP_READONLY_RECORD_HEADER_P(lheader) ((lheader)->lisp_readonly)
310 #define SET_C_READONLY_RECORD_HEADER(lheader) do { \
311 struct lrecord_header *SCRRH_lheader = (lheader); \
312 SCRRH_lheader->c_readonly = 1; \
313 SCRRH_lheader->lisp_readonly = 1; \
314 SCRRH_lheader->mark = 1; \
316 #define SET_LISP_READONLY_RECORD_HEADER(lheader) \
317 ((void) ((lheader)->lisp_readonly = 1))
318 #define RECORD_MARKER(lheader) lrecord_markers[(lheader)->type]
320 /* External description stuff
322 A lrecord external description is an array of values. The first
323 value of each line is a type, the second the offset in the lrecord
324 structure. Following values are parameters, their presence, type
325 and number is type-dependant.
327 The description ends with a "XD_END" or "XD_SPECIFIER_END" record.
329 Some example descriptions :
331 static const struct lrecord_description cons_description[] = {
332 { XD_LISP_OBJECT, offsetof (Lisp_Cons, car) },
333 { XD_LISP_OBJECT, offsetof (Lisp_Cons, cdr) },
337 Which means "two lisp objects starting at the 'car' and 'cdr' elements"
339 static const struct lrecord_description string_description[] = {
340 { XD_BYTECOUNT, offsetof (Lisp_String, size) },
341 { XD_OPAQUE_DATA_PTR, offsetof (Lisp_String, data), XD_INDIRECT(0, 1) },
342 { XD_LISP_OBJECT, offsetof (Lisp_String, plist) },
345 "A pointer to string data at 'data', the size of the pointed array being the value
346 of the size variable plus 1, and one lisp object at 'plist'"
350 A Lisp object. This is also the type to use for pointers to other lrecords.
353 An array of Lisp objects or pointers to lrecords.
354 The third element is the count.
357 Lisp objects which will be reset to Qnil when dumping. Useful for cleaning
361 Link in a linked list of objects of the same type.
364 Pointer to undumpable data. Must be NULL when dumping.
367 Pointer to described struct. Parameters are number of structures and
371 Pointer to dumpable opaque data. Parameter is the size of the data.
372 Pointed data must be relocatable without changes.
375 Pointer to a C string.
378 Pointer to a doc string (C string if positive, opaque value if negative)
381 An integer which will be reset to a given value in the dump file.
385 size_t value. Used for counts.
388 int value. Used for counts.
391 long value. Used for counts.
394 bytecount value. Used for counts.
397 Special type indicating the end of the array.
400 Special type indicating the end of the array for a specifier. Extra
401 description is going to be fetched from the specifier methods.
405 XD_INDIRECT(line, delta)
406 Usable where a "count" or "size" is requested. Gives the value of
407 the element which is at line number 'line' in the description (count
408 starts at zero) and adds delta to it.
411 enum lrecord_description_type {
412 XD_LISP_OBJECT_ARRAY,
430 struct lrecord_description {
431 enum lrecord_description_type type;
434 const struct struct_description *data2;
437 struct struct_description {
439 const struct lrecord_description *description;
442 #define XD_INDIRECT(val, delta) (-1-((val)|(delta<<8)))
444 #define XD_IS_INDIRECT(code) (code<0)
445 #define XD_INDIRECT_VAL(code) ((-1-code) & 255)
446 #define XD_INDIRECT_DELTA(code) (((-1-code)>>8) & 255)
448 #define XD_DYNARR_DESC(base_type, sub_desc) \
449 { XD_STRUCT_PTR, offsetof (base_type, base), XD_INDIRECT(1, 0), sub_desc }, \
450 { XD_INT, offsetof (base_type, cur) }, \
451 { XD_INT_RESET, offsetof (base_type, max), XD_INDIRECT(1, 0) }
453 /* DEFINE_LRECORD_IMPLEMENTATION is for objects with constant size.
454 DEFINE_LRECORD_SEQUENCE_IMPLEMENTATION is for objects whose size varies.
457 #if defined (ERROR_CHECK_TYPECHECK)
458 # define DECLARE_ERROR_CHECK_TYPECHECK(c_name, structtype)
460 # define DECLARE_ERROR_CHECK_TYPECHECK(c_name, structtype)
463 #define DEFINE_BASIC_LRECORD_IMPLEMENTATION(name,c_name,marker,printer,nuker,equal,hash,desc,structtype) \
464 DEFINE_BASIC_LRECORD_IMPLEMENTATION_WITH_PROPS(name,c_name,marker,printer,nuker,equal,hash,desc,0,0,0,0,structtype)
466 #define DEFINE_BASIC_LRECORD_IMPLEMENTATION_WITH_PROPS(name,c_name,marker,printer,nuker,equal,hash,desc,getprop,putprop,remprop,plist,structtype) \
467 MAKE_LRECORD_IMPLEMENTATION(name,c_name,marker,printer,nuker,equal,hash,desc,getprop,putprop,remprop,plist,sizeof(structtype),0,1,structtype)
469 #define DEFINE_LRECORD_IMPLEMENTATION(name,c_name,marker,printer,nuker,equal,hash,desc,structtype) \
470 DEFINE_LRECORD_IMPLEMENTATION_WITH_PROPS(name,c_name,marker,printer,nuker,equal,hash,desc,0,0,0,0,structtype)
472 #define DEFINE_LRECORD_IMPLEMENTATION_WITH_PROPS(name,c_name,marker,printer,nuker,equal,hash,desc,getprop,putprop,remprop,plist,structtype) \
473 MAKE_LRECORD_IMPLEMENTATION(name,c_name,marker,printer,nuker,equal,hash,desc,getprop,putprop,remprop,plist,sizeof (structtype),0,0,structtype)
475 #define DEFINE_LRECORD_SEQUENCE_IMPLEMENTATION(name,c_name,marker,printer,nuker,equal,hash,desc,sizer,structtype) \
476 DEFINE_LRECORD_SEQUENCE_IMPLEMENTATION_WITH_PROPS(name,c_name,marker,printer,nuker,equal,hash,desc,0,0,0,0,sizer,structtype)
478 #define DEFINE_BASIC_LRECORD_SEQUENCE_IMPLEMENTATION(name,c_name,marker,printer,nuker,equal,hash,desc,sizer,structtype) \
479 MAKE_LRECORD_IMPLEMENTATION(name,c_name,marker,printer,nuker,equal,hash,desc,0,0,0,0,0,sizer,1,structtype)
481 #define DEFINE_LRECORD_SEQUENCE_IMPLEMENTATION_WITH_PROPS(name,c_name,marker,printer,nuker,equal,hash,desc,getprop,putprop,remprop,plist,sizer,structtype) \
482 MAKE_LRECORD_IMPLEMENTATION(name,c_name,marker,printer,nuker,equal,hash,desc,getprop,putprop,remprop,plist,0,sizer,0,structtype) \
484 #define MAKE_LRECORD_IMPLEMENTATION(name,c_name,marker,printer,nuker,equal,hash,desc,getprop,putprop,remprop,plist,size,sizer,basic_p,structtype) \
485 DECLARE_ERROR_CHECK_TYPECHECK(c_name, structtype) \
486 const struct lrecord_implementation lrecord_##c_name = \
487 { name, marker, printer, nuker, equal, hash, desc, \
488 getprop, putprop, remprop, plist, size, sizer, \
489 lrecord_type_##c_name, basic_p }
491 extern Lisp_Object (*lrecord_markers[]) (Lisp_Object);
493 #define INIT_LRECORD_IMPLEMENTATION(type) do { \
494 lrecord_implementations_table[lrecord_type_##type] = &lrecord_##type; \
495 lrecord_markers[lrecord_type_##type] = \
496 lrecord_implementations_table[lrecord_type_##type]->marker; \
499 #define LRECORDP(a) (XTYPE (a) == Lisp_Type_Record)
500 #define XRECORD_LHEADER(a) ((struct lrecord_header *) XPNTR (a))
502 #define RECORD_TYPEP(x, ty) \
503 (LRECORDP (x) && XRECORD_LHEADER (x)->type == (ty))
505 /* NOTE: the DECLARE_LRECORD() must come before the associated
506 DEFINE_LRECORD_*() or you will get compile errors.
508 Furthermore, you always need to put the DECLARE_LRECORD() in a header
509 file, and make sure the header file is included in inline.c, even
510 if the type is private to a particular file. Otherwise, you will
511 get undefined references for the error_check_foo() inline function
514 #ifdef ERROR_CHECK_TYPECHECK
516 # define DECLARE_LRECORD(c_name, structtype) \
517 extern const struct lrecord_implementation lrecord_##c_name; \
518 INLINE_HEADER structtype * \
519 error_check_##c_name (Lisp_Object obj); \
520 INLINE_HEADER structtype * \
521 error_check_##c_name (Lisp_Object obj) \
523 assert (RECORD_TYPEP (obj, lrecord_type_##c_name)); \
524 return (structtype *) XPNTR (obj); \
526 extern Lisp_Object Q##c_name##p
528 # define DECLARE_NONRECORD(c_name, type_enum, structtype) \
529 INLINE_HEADER structtype * \
530 error_check_##c_name (Lisp_Object obj); \
531 INLINE_HEADER structtype * \
532 error_check_##c_name (Lisp_Object obj) \
534 assert (XTYPE (obj) == type_enum); \
535 return (structtype *) XPNTR (obj); \
537 extern Lisp_Object Q##c_name##p
539 # define XRECORD(x, c_name, structtype) error_check_##c_name (x)
540 # define XNONRECORD(x, c_name, type_enum, structtype) error_check_##c_name (x)
542 # define XSETRECORD(var, p, c_name) do \
544 XSETOBJ (var, Lisp_Type_Record, p); \
545 assert (RECORD_TYPEP (var, lrecord_type_##c_name)); \
548 #else /* not ERROR_CHECK_TYPECHECK */
550 # define DECLARE_LRECORD(c_name, structtype) \
551 extern Lisp_Object Q##c_name##p; \
552 extern const struct lrecord_implementation lrecord_##c_name
553 # define DECLARE_NONRECORD(c_name, type_enum, structtype) \
554 extern Lisp_Object Q##c_name##p
555 # define XRECORD(x, c_name, structtype) ((structtype *) XPNTR (x))
556 # define XNONRECORD(x, c_name, type_enum, structtype) \
557 ((structtype *) XPNTR (x))
558 # define XSETRECORD(var, p, c_name) XSETOBJ (var, Lisp_Type_Record, p)
560 #endif /* not ERROR_CHECK_TYPECHECK */
562 #define RECORDP(x, c_name) RECORD_TYPEP (x, lrecord_type_##c_name)
564 /* Note: we now have two different kinds of type-checking macros.
565 The "old" kind has now been renamed CONCHECK_foo. The reason for
566 this is that the CONCHECK_foo macros signal a continuable error,
567 allowing the user (through debug-on-error) to substitute a different
568 value and return from the signal, which causes the lvalue argument
569 to get changed. Quite a lot of code would crash if that happened,
570 because it did things like
575 and later on did XSTRING (XCAR (list)), assuming that the type
576 is correct (when it might be wrong, if the user substituted a
577 correct value in the debugger).
579 To get around this, I made all the CHECK_foo macros signal a
580 non-continuable error. Places where a continuable error is OK
581 (generally only when called directly on the argument of a Lisp
582 primitive) should be changed to use CONCHECK().
584 FSF Emacs does not have this problem because RMS took the cheesy
585 way out and disabled returning from a signal entirely. */
587 #define CONCHECK_RECORD(x, c_name) do { \
588 if (!RECORD_TYPEP (x, lrecord_type_##c_name)) \
589 x = wrong_type_argument (Q##c_name##p, x); \
591 #define CONCHECK_NONRECORD(x, lisp_enum, predicate) do {\
592 if (XTYPE (x) != lisp_enum) \
593 x = wrong_type_argument (predicate, x); \
595 #define CHECK_RECORD(x, c_name) do { \
596 if (!RECORD_TYPEP (x, lrecord_type_##c_name)) \
597 dead_wrong_type_argument (Q##c_name##p, x); \
599 #define CHECK_NONRECORD(x, lisp_enum, predicate) do { \
600 if (XTYPE (x) != lisp_enum) \
601 dead_wrong_type_argument (predicate, x); \
604 void *alloc_lcrecord (size_t size, const struct lrecord_implementation *);
606 #define alloc_lcrecord_type(type, lrecord_implementation) \
607 ((type *) alloc_lcrecord (sizeof (type), lrecord_implementation))
611 alloc_older_lcrecord (size_t size, const struct lrecord_implementation *);
613 #define alloc_older_lcrecord_type(type, lrecord_implementation) \
614 ((type *) alloc_older_lcrecord (sizeof (type), lrecord_implementation))
617 /* Copy the data from one lcrecord structure into another, but don't
618 overwrite the header information. */
620 #define copy_lcrecord(dst, src) \
621 memcpy ((char *) (dst) + sizeof (struct lcrecord_header), \
622 (char *) (src) + sizeof (struct lcrecord_header), \
623 sizeof (*(dst)) - sizeof (struct lcrecord_header))
625 #define zero_lcrecord(lcr) \
626 memset ((char *) (lcr) + sizeof (struct lcrecord_header), 0, \
627 sizeof (*(lcr)) - sizeof (struct lcrecord_header))
629 #endif /* INCLUDED_lrecord_h_ */