1 /* XEmacs routines to deal with range tables.
2 Copyright (C) 1995 Sun Microsystems, Inc.
3 Copyright (C) 1995 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 /* Written by Ben Wing, August 1995. */
30 Lisp_Object Qrange_tablep;
31 Lisp_Object Qrange_table;
34 /************************************************************************/
35 /* Range table object */
36 /************************************************************************/
38 /* We use a sorted array of ranges.
40 #### We should be using the gap array stuff from extents.c. This
41 is not hard but just requires moving that stuff out of that file. */
44 mark_range_table (Lisp_Object obj)
46 Lisp_Range_Table *rt = XRANGE_TABLE (obj);
49 for (i = 0; i < Dynarr_length (rt->entries); i++)
50 mark_object (Dynarr_at (rt->entries, i).val);
55 print_range_table (Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
57 Lisp_Range_Table *rt = XRANGE_TABLE (obj);
61 write_c_string ("#s(range-table data (", printcharfun);
62 for (i = 0; i < Dynarr_length (rt->entries); i++)
64 struct range_table_entry *rte = Dynarr_atp (rt->entries, i);
66 write_c_string (" ", printcharfun);
67 if (rte->first == rte->last)
68 sprintf (buf, "%ld ", (long) (rte->first));
70 sprintf (buf, "(%ld %ld) ", (long) (rte->first), (long) (rte->last));
71 write_c_string (buf, printcharfun);
72 print_internal (rte->val, printcharfun, 1);
74 write_c_string ("))", printcharfun);
78 range_table_equal (Lisp_Object obj1, Lisp_Object obj2, int depth)
80 Lisp_Range_Table *rt1 = XRANGE_TABLE (obj1);
81 Lisp_Range_Table *rt2 = XRANGE_TABLE (obj2);
84 if (Dynarr_length (rt1->entries) != Dynarr_length (rt2->entries))
87 for (i = 0; i < Dynarr_length (rt1->entries); i++)
89 struct range_table_entry *rte1 = Dynarr_atp (rt1->entries, i);
90 struct range_table_entry *rte2 = Dynarr_atp (rt2->entries, i);
92 if (rte1->first != rte2->first
93 || rte1->last != rte2->last
94 || !internal_equal (rte1->val, rte2->val, depth + 1))
102 range_table_entry_hash (struct range_table_entry *rte, int depth)
104 return HASH3 (rte->first, rte->last, internal_hash (rte->val, depth + 1));
108 range_table_hash (Lisp_Object obj, int depth)
110 Lisp_Range_Table *rt = XRANGE_TABLE (obj);
112 int size = Dynarr_length (rt->entries);
113 unsigned long hash = size;
115 /* approach based on internal_array_hash(). */
118 for (i = 0; i < size; i++)
120 range_table_entry_hash (Dynarr_atp (rt->entries, i),
125 /* just pick five elements scattered throughout the array.
126 A slightly better approach would be to offset by some
127 noise factor from the points chosen below. */
128 for (i = 0; i < 5; i++)
129 hash = HASH2 (hash, range_table_entry_hash (Dynarr_atp (rt->entries,
135 static const struct lrecord_description rte_description_1[] = {
136 { XD_LISP_OBJECT, offsetof (range_table_entry, val) },
140 static const struct struct_description rte_description = {
141 sizeof (range_table_entry),
145 static const struct lrecord_description rted_description_1[] = {
146 XD_DYNARR_DESC (range_table_entry_dynarr, &rte_description),
150 static const struct struct_description rted_description = {
151 sizeof (range_table_entry_dynarr),
155 static const struct lrecord_description range_table_description[] = {
156 { XD_STRUCT_PTR, offsetof (Lisp_Range_Table, entries), 1, &rted_description },
160 DEFINE_LRECORD_IMPLEMENTATION ("range-table", range_table,
161 mark_range_table, print_range_table, 0,
162 range_table_equal, range_table_hash,
163 range_table_description,
166 /************************************************************************/
167 /* Range table operations */
168 /************************************************************************/
170 #ifdef ERROR_CHECK_TYPECHECK
173 verify_range_table (Lisp_Range_Table *rt)
177 for (i = 0; i < Dynarr_length (rt->entries); i++)
179 struct range_table_entry *rte = Dynarr_atp (rt->entries, i);
180 assert (rte->last >= rte->first);
182 assert (Dynarr_at (rt->entries, i - 1).last < rte->first);
188 #define verify_range_table(rt)
192 /* Look up in a range table without the Dynarr wrapper.
193 Used also by the unified range table format. */
196 get_range_table (EMACS_INT pos, int nentries, struct range_table_entry *tab,
197 Lisp_Object default_)
199 int left = 0, right = nentries;
201 /* binary search for the entry. Based on similar code in
202 extent_list_locate(). */
203 while (left != right)
205 /* RIGHT might not point to a valid entry (i.e. it's at the end
206 of the list), so NEWPOS must round down. */
207 unsigned int newpos = (left + right) >> 1;
208 struct range_table_entry *entry = tab + newpos;
209 if (pos > entry->last)
211 else if (pos < entry->first)
220 DEFUN ("range-table-p", Frange_table_p, 1, 1, 0, /*
221 Return non-nil if OBJECT is a range table.
225 return RANGE_TABLEP (object) ? Qt : Qnil;
228 DEFUN ("make-range-table", Fmake_range_table, 0, 0, 0, /*
229 Return a new, empty range table.
230 You can manipulate it using `put-range-table', `get-range-table',
231 `remove-range-table', and `clear-range-table'.
236 Lisp_Range_Table *rt = alloc_lcrecord_type (Lisp_Range_Table,
237 &lrecord_range_table);
238 rt->entries = Dynarr_new (range_table_entry);
239 XSETRANGE_TABLE (obj, rt);
243 DEFUN ("copy-range-table", Fcopy_range_table, 1, 1, 0, /*
244 Make a new range table which contains the same values for the same
245 ranges as the given table. The values will not themselves be copied.
249 Lisp_Range_Table *rt, *rtnew;
252 CHECK_RANGE_TABLE (old_table);
253 rt = XRANGE_TABLE (old_table);
255 rtnew = alloc_lcrecord_type (Lisp_Range_Table, &lrecord_range_table);
256 rtnew->entries = Dynarr_new (range_table_entry);
258 Dynarr_add_many (rtnew->entries, Dynarr_atp (rt->entries, 0),
259 Dynarr_length (rt->entries));
260 XSETRANGE_TABLE (obj, rtnew);
264 DEFUN ("get-range-table", Fget_range_table, 2, 3, 0, /*
265 Find value for position POS in TABLE.
266 If there is no corresponding value, return DEFAULT (defaults to nil).
268 (pos, table, default_))
270 Lisp_Range_Table *rt;
272 CHECK_RANGE_TABLE (table);
273 rt = XRANGE_TABLE (table);
275 CHECK_INT_COERCE_CHAR (pos);
277 return get_range_table (XINT (pos), Dynarr_length (rt->entries),
278 Dynarr_atp (rt->entries, 0), default_);
282 put_range_table (Lisp_Object table, EMACS_INT first,
283 EMACS_INT last, Lisp_Object val)
286 int insert_me_here = -1;
287 Lisp_Range_Table *rt = XRANGE_TABLE (table);
289 /* Now insert in the proper place. This gets tricky because
290 we may be overlapping one or more existing ranges and need
293 /* First delete all sections of any existing ranges that overlap
295 for (i = 0; i < Dynarr_length (rt->entries); i++)
297 struct range_table_entry *entry = Dynarr_atp (rt->entries, i);
298 /* We insert before the first range that begins at or after the
300 if (entry->first >= first && insert_me_here < 0)
302 if (entry->last < first)
303 /* completely before the new range. */
305 if (entry->first > last)
306 /* completely after the new range. No more possibilities of
307 finding overlapping ranges. */
309 if (entry->first < first && entry->last <= last)
317 /* truncate the end off of it. */
318 entry->last = first - 1;
320 else if (entry->first < first && entry->last > last)
327 /* need to split this one in two. */
329 struct range_table_entry insert_me_too;
331 insert_me_too.first = last + 1;
332 insert_me_too.last = entry->last;
333 insert_me_too.val = entry->val;
334 entry->last = first - 1;
335 Dynarr_insert_many (rt->entries, &insert_me_too, 1, i + 1);
337 else if (entry->last > last)
345 /* truncate the start off of it. */
346 entry->first = last + 1;
350 /* existing is entirely within new. */
351 Dynarr_delete_many (rt->entries, i, 1);
352 i--; /* back up since everything shifted one to the left. */
356 /* Someone asked us to delete the range, not insert it. */
360 /* Now insert the new entry, maybe at the end. */
362 if (insert_me_here < 0)
366 struct range_table_entry insert_me;
368 insert_me.first = first;
369 insert_me.last = last;
372 Dynarr_insert_many (rt->entries, &insert_me, 1, insert_me_here);
375 /* Now see if we can combine this entry with adjacent ones just
378 if (insert_me_here > 0)
380 struct range_table_entry *entry = Dynarr_atp (rt->entries,
382 if (EQ (val, entry->val) && entry->last == first - 1)
385 Dynarr_delete_many (rt->entries, insert_me_here, 1);
387 /* We have morphed into a larger range. Update our records
388 in case we also combine with the one after. */
389 first = entry->first;
393 if (insert_me_here < Dynarr_length (rt->entries) - 1)
395 struct range_table_entry *entry = Dynarr_atp (rt->entries,
397 if (EQ (val, entry->val) && entry->first == last + 1)
399 entry->first = first;
400 Dynarr_delete_many (rt->entries, insert_me_here, 1);
405 DEFUN ("put-range-table", Fput_range_table, 4, 4, 0, /*
406 Set the value for range (START, END) to be VAL in TABLE.
408 (start, end, val, table))
410 EMACS_INT first, last;
412 CHECK_RANGE_TABLE (table);
413 CHECK_INT_COERCE_CHAR (start);
414 first = XINT (start);
415 CHECK_INT_COERCE_CHAR (end);
418 signal_simple_error_2 ("start must be <= end", start, end);
420 put_range_table (table, first, last, val);
421 verify_range_table (XRANGE_TABLE (table));
425 DEFUN ("remove-range-table", Fremove_range_table, 3, 3, 0, /*
426 Remove the value for range (START, END) in TABLE.
430 return Fput_range_table (start, end, Qunbound, table);
433 DEFUN ("clear-range-table", Fclear_range_table, 1, 1, 0, /*
438 CHECK_RANGE_TABLE (table);
439 Dynarr_reset (XRANGE_TABLE (table)->entries);
443 DEFUN ("map-range-table", Fmap_range_table, 2, 2, 0, /*
444 Map FUNCTION over entries in TABLE, calling it with three args,
445 the beginning and end of the range and the corresponding value.
447 Results are guaranteed to be correct (i.e. each entry processed
448 exactly once) if FUNCTION modifies or deletes the current entry
449 (i.e. passes the current range to `put-range-table' or
450 `remove-range-table'), but not otherwise.
454 Lisp_Range_Table *rt;
457 CHECK_RANGE_TABLE (table);
458 CHECK_FUNCTION (function);
460 rt = XRANGE_TABLE (table);
462 /* Do not "optimize" by pulling out the length computation below!
463 FUNCTION may have changed the table. */
464 for (i = 0; i < Dynarr_length (rt->entries); i++)
466 struct range_table_entry *entry = Dynarr_atp (rt->entries, i);
467 EMACS_INT first, last;
472 first = entry->first;
474 oldlen = Dynarr_length (rt->entries);
476 args[1] = make_int (first);
477 args[2] = make_int (last);
478 args[3] = entry->val;
479 Ffuncall (countof (args), args);
480 /* Has FUNCTION removed the entry? */
481 if (oldlen > Dynarr_length (rt->entries)
482 && i < Dynarr_length (rt->entries)
483 && (first != entry->first || last != entry->last))
491 /************************************************************************/
492 /* Range table read syntax */
493 /************************************************************************/
496 rangetab_data_validate (Lisp_Object keyword, Lisp_Object value,
501 /* #### should deal with errb */
502 EXTERNAL_LIST_LOOP (rest, value)
504 Lisp_Object range = XCAR (rest);
507 signal_simple_error ("Invalid list format", value);
508 if (!INTP (range) && !CHARP (range)
509 && !(CONSP (range) && CONSP (XCDR (range))
510 && NILP (XCDR (XCDR (range)))
511 && (INTP (XCAR (range)) || CHARP (XCAR (range)))
512 && (INTP (XCAR (XCDR (range))) || CHARP (XCAR (XCDR (range))))))
513 signal_simple_error ("Invalid range format", range);
520 rangetab_instantiate (Lisp_Object data)
522 Lisp_Object rangetab = Fmake_range_table ();
526 data = Fcar (Fcdr (data)); /* skip over 'data keyword */
529 Lisp_Object range = Fcar (data);
530 Lisp_Object val = Fcar (Fcdr (data));
532 data = Fcdr (Fcdr (data));
534 Fput_range_table (Fcar (range), Fcar (Fcdr (range)), val,
537 Fput_range_table (range, range, val, rangetab);
545 /************************************************************************/
546 /* Unified range tables */
547 /************************************************************************/
549 /* A "unified range table" is a format for storing range tables
550 as contiguous blocks of memory. This is used by the regexp
551 code, which needs to use range tables to properly handle []
552 constructs in the presence of extended characters but wants to
553 store an entire compiled pattern as a contiguous block of memory.
555 Unified range tables are designed so that they can be placed
556 at an arbitrary (possibly mis-aligned) place in memory.
557 (Dealing with alignment is a pain in the ass.)
559 WARNING: No provisions for garbage collection are currently made.
560 This means that there must not be any Lisp objects in a unified
561 range table that need to be marked for garbage collection.
562 Good candidates for objects that can go into a range table are
564 -- numbers and characters (do not need to be marked)
565 -- nil, t (marked elsewhere)
566 -- charsets and coding systems (automatically marked because
567 they are in a marked list,
568 and can't be removed)
570 Good but slightly less so:
572 -- symbols (could be uninterned, but that is not likely)
576 -- buffers, frames, devices (could get deleted)
579 It is expected that you work with range tables in the normal
580 format and then convert to unified format when you are done
581 making modifications. As such, no functions are provided
582 for modifying a unified range table. The only operations
583 you can do to unified range tables are
586 -- retrieve all the ranges in an iterative fashion
590 /* The format of a unified range table is as follows:
592 -- The first byte contains the number of bytes to skip to find the
593 actual start of the table. This deals with alignment constraints,
594 since the table might want to go at any arbitrary place in memory.
595 -- The next three bytes contain the number of bytes to skip (from the
596 *first* byte) to find the stuff after the table. It's stored in
597 little-endian format because that's how God intended things. We don't
598 necessarily start the stuff at the very end of the table because
599 we want to have at least ALIGNOF (EMACS_INT) extra space in case
600 we have to move the range table around. (It appears that some
601 architectures don't maintain alignment when reallocing.)
602 -- At the prescribed offset is a struct unified_range_table, containing
603 some number of `struct range_table_entry' entries. */
605 struct unified_range_table
608 struct range_table_entry first;
611 /* Return size in bytes needed to store the data in a range table. */
614 unified_range_table_bytes_needed (Lisp_Object rangetab)
616 return (sizeof (struct range_table_entry) *
617 (Dynarr_length (XRANGE_TABLE (rangetab)->entries) - 1) +
618 sizeof (struct unified_range_table) +
619 /* ALIGNOF a struct may be too big. */
620 /* We have four bytes for the size numbers, and an extra
621 four or eight bytes for making sure we get the alignment
623 ALIGNOF (EMACS_INT) + 4);
626 /* Convert a range table into unified format and store in DEST,
627 which must be able to hold the number of bytes returned by
628 range_table_bytes_needed(). */
631 unified_range_table_copy_data (Lisp_Object rangetab, void *dest)
633 /* We cast to the above structure rather than just casting to
634 char * and adding sizeof(int), because that will lead to
635 mis-aligned data on the Alpha machines. */
636 struct unified_range_table *un;
637 range_table_entry_dynarr *rted = XRANGE_TABLE (rangetab)->entries;
638 int total_needed = unified_range_table_bytes_needed (rangetab);
639 void *new_dest = ALIGN_PTR ((char *) dest + 4, ALIGNOF (EMACS_INT));
641 * (char *) dest = (char) ((char *) new_dest - (char *) dest);
642 * ((unsigned char *) dest + 1) = total_needed & 0xFF;
644 * ((unsigned char *) dest + 2) = total_needed & 0xFF;
646 * ((unsigned char *) dest + 3) = total_needed & 0xFF;
647 un = (struct unified_range_table *) new_dest;
648 un->nentries = Dynarr_length (rted);
649 memcpy (&un->first, Dynarr_atp (rted, 0),
650 sizeof (struct range_table_entry) * Dynarr_length (rted));
653 /* Return number of bytes actually used by a unified range table. */
656 unified_range_table_bytes_used (void *unrangetab)
658 return ((* ((unsigned char *) unrangetab + 1))
659 + ((* ((unsigned char *) unrangetab + 2)) << 8)
660 + ((* ((unsigned char *) unrangetab + 3)) << 16));
663 /* Make sure the table is aligned, and move it around if it's not. */
665 align_the_damn_table (void *unrangetab)
667 void *cur_dest = (char *) unrangetab + * (char *) unrangetab;
669 if ((((long) cur_dest) & 7) != 0)
671 if ((((int) cur_dest) & 3) != 0)
674 int count = (unified_range_table_bytes_used (unrangetab) - 4
675 - ALIGNOF (EMACS_INT));
676 /* Find the proper location, just like above. */
677 void *new_dest = ALIGN_PTR ((char *) unrangetab + 4,
678 ALIGNOF (EMACS_INT));
679 /* memmove() works in the presence of overlapping data. */
680 memmove (new_dest, cur_dest, count);
681 * (char *) unrangetab = (char) ((char *) new_dest - (char *) unrangetab);
685 /* Look up a value in a unified range table. */
688 unified_range_table_lookup (void *unrangetab, EMACS_INT pos,
689 Lisp_Object default_)
692 struct unified_range_table *un;
694 align_the_damn_table (unrangetab);
695 new_dest = (char *) unrangetab + * (char *) unrangetab;
696 un = (struct unified_range_table *) new_dest;
698 return get_range_table (pos, un->nentries, &un->first, default_);
701 /* Return number of entries in a unified range table. */
704 unified_range_table_nentries (void *unrangetab)
707 struct unified_range_table *un;
709 align_the_damn_table (unrangetab);
710 new_dest = (char *) unrangetab + * (char *) unrangetab;
711 un = (struct unified_range_table *) new_dest;
715 /* Return the OFFSETth range (counting from 0) in UNRANGETAB. */
717 unified_range_table_get_range (void *unrangetab, int offset,
718 EMACS_INT *min, EMACS_INT *max,
722 struct unified_range_table *un;
723 struct range_table_entry *tab;
725 align_the_damn_table (unrangetab);
726 new_dest = (char *) unrangetab + * (char *) unrangetab;
727 un = (struct unified_range_table *) new_dest;
729 assert (offset >= 0 && offset < un->nentries);
730 tab = (&un->first) + offset;
737 /************************************************************************/
739 /************************************************************************/
742 syms_of_rangetab (void)
744 INIT_LRECORD_IMPLEMENTATION (range_table);
746 defsymbol (&Qrange_tablep, "range-table-p");
747 defsymbol (&Qrange_table, "range-table");
749 DEFSUBR (Frange_table_p);
750 DEFSUBR (Fmake_range_table);
751 DEFSUBR (Fcopy_range_table);
752 DEFSUBR (Fget_range_table);
753 DEFSUBR (Fput_range_table);
754 DEFSUBR (Fremove_range_table);
755 DEFSUBR (Fclear_range_table);
756 DEFSUBR (Fmap_range_table);
760 structure_type_create_rangetab (void)
762 struct structure_type *st;
764 st = define_structure_type (Qrange_table, 0, rangetab_instantiate);
766 define_structure_type_keyword (st, Qdata, rangetab_data_validate);