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, void (*markobj) (Lisp_Object))
46 struct Lisp_Range_Table *rt = XRANGE_TABLE (obj);
49 for (i = 0; i < Dynarr_length (rt->entries); i++)
50 (markobj) (Dynarr_at (rt->entries, i).val);
55 print_range_table (Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
57 struct 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 struct Lisp_Range_Table *rt1 = XRANGE_TABLE (obj1);
81 struct 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 struct 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 DEFINE_LRECORD_IMPLEMENTATION ("range-table", range_table,
136 mark_range_table, print_range_table, 0,
137 range_table_equal, range_table_hash,
138 struct Lisp_Range_Table);
140 /************************************************************************/
141 /* Range table operations */
142 /************************************************************************/
144 #ifdef ERROR_CHECK_TYPECHECK
147 verify_range_table (struct Lisp_Range_Table *rt)
151 for (i = 0; i < Dynarr_length (rt->entries); i++)
153 struct range_table_entry *rte = Dynarr_atp (rt->entries, i);
154 assert (rte->last >= rte->first);
156 assert (Dynarr_at (rt->entries, i - 1).last < rte->first);
162 #define verify_range_table(rt)
166 /* Look up in a range table without the Dynarr wrapper.
167 Used also by the unified range table format. */
170 get_range_table (EMACS_INT pos, int nentries, struct range_table_entry *tab,
171 Lisp_Object default_)
173 int left = 0, right = nentries;
175 /* binary search for the entry. Based on similar code in
176 extent_list_locate(). */
177 while (left != right)
179 /* RIGHT might not point to a valid entry (i.e. it's at the end
180 of the list), so NEWPOS must round down. */
181 unsigned int newpos = (left + right) >> 1;
182 struct range_table_entry *entry = tab + newpos;
183 if (pos > entry->last)
185 else if (pos < entry->first)
194 DEFUN ("range-table-p", Frange_table_p, 1, 1, 0, /*
195 Return non-nil if OBJECT is a range table.
199 return RANGE_TABLEP (object) ? Qt : Qnil;
202 DEFUN ("make-range-table", Fmake_range_table, 0, 0, 0, /*
203 Return a new, empty range table.
204 You can manipulate it using `put-range-table', `get-range-table',
205 `remove-range-table', and `clear-range-table'.
210 struct Lisp_Range_Table *rt = alloc_lcrecord_type (struct Lisp_Range_Table,
211 lrecord_range_table);
212 rt->entries = Dynarr_new (range_table_entry);
213 XSETRANGE_TABLE (obj, rt);
217 DEFUN ("copy-range-table", Fcopy_range_table, 1, 1, 0, /*
218 Make a new range table which contains the same values for the same
219 ranges as the given table. The values will not themselves be copied.
223 struct Lisp_Range_Table *rt, *rtnew;
226 CHECK_RANGE_TABLE (old_table);
227 rt = XRANGE_TABLE (old_table);
229 rtnew = alloc_lcrecord_type (struct Lisp_Range_Table, lrecord_range_table);
230 rtnew->entries = Dynarr_new (range_table_entry);
232 Dynarr_add_many (rtnew->entries, Dynarr_atp (rt->entries, 0),
233 Dynarr_length (rt->entries));
234 XSETRANGE_TABLE (obj, rtnew);
238 DEFUN ("get-range-table", Fget_range_table, 2, 3, 0, /*
239 Find value for position POS in TABLE.
240 If there is no corresponding value, return DEFAULT (defaults to nil).
242 (pos, table, default_))
244 struct Lisp_Range_Table *rt;
247 CHECK_RANGE_TABLE (table);
248 rt = XRANGE_TABLE (table);
250 CHECK_INT_COERCE_CHAR (pos);
253 return get_range_table (po, Dynarr_length (rt->entries),
254 Dynarr_atp (rt->entries, 0), default_);
258 put_range_table (Lisp_Object table, EMACS_INT first,
259 EMACS_INT last, Lisp_Object val)
262 int insert_me_here = -1;
263 struct Lisp_Range_Table *rt = XRANGE_TABLE (table);
265 /* Now insert in the proper place. This gets tricky because
266 we may be overlapping one or more existing ranges and need
269 /* First delete all sections of any existing ranges that overlap
271 for (i = 0; i < Dynarr_length (rt->entries); i++)
273 struct range_table_entry *entry = Dynarr_atp (rt->entries, i);
274 /* We insert before the first range that begins at or after the
276 if (entry->first >= first && insert_me_here < 0)
278 if (entry->last < first)
279 /* completely before the new range. */
281 if (entry->first > last)
282 /* completely after the new range. No more possibilities of
283 finding overlapping ranges. */
285 if (entry->first < first && entry->last <= last)
293 /* truncate the end off of it. */
294 entry->last = first - 1;
296 else if (entry->first < first && entry->last > last)
303 /* need to split this one in two. */
305 struct range_table_entry insert_me_too;
307 insert_me_too.first = last + 1;
308 insert_me_too.last = entry->last;
309 insert_me_too.val = entry->val;
310 entry->last = first - 1;
311 Dynarr_insert_many (rt->entries, &insert_me_too, 1, i + 1);
313 else if (entry->last > last)
321 /* truncate the start off of it. */
322 entry->first = last + 1;
326 /* existing is entirely within new. */
327 Dynarr_delete_many (rt->entries, i, 1);
328 i--; /* back up since everything shifted one to the left. */
332 /* Someone asked us to delete the range, not insert it. */
336 /* Now insert the new entry, maybe at the end. */
338 if (insert_me_here < 0)
342 struct range_table_entry insert_me;
344 insert_me.first = first;
345 insert_me.last = last;
348 Dynarr_insert_many (rt->entries, &insert_me, 1, insert_me_here);
351 /* Now see if we can combine this entry with adjacent ones just
354 if (insert_me_here > 0)
356 struct range_table_entry *entry = Dynarr_atp (rt->entries,
358 if (EQ (val, entry->val) && entry->last == first - 1)
361 Dynarr_delete_many (rt->entries, insert_me_here, 1);
363 /* We have morphed into a larger range. Update our records
364 in case we also combine with the one after. */
365 first = entry->first;
369 if (insert_me_here < Dynarr_length (rt->entries) - 1)
371 struct range_table_entry *entry = Dynarr_atp (rt->entries,
373 if (EQ (val, entry->val) && entry->first == last + 1)
375 entry->first = first;
376 Dynarr_delete_many (rt->entries, insert_me_here, 1);
381 DEFUN ("put-range-table", Fput_range_table, 4, 4, 0, /*
382 Set the value for range (START, END) to be VAL in TABLE.
384 (start, end, val, table))
386 EMACS_INT first, last;
388 CHECK_RANGE_TABLE (table);
389 CHECK_INT_COERCE_CHAR (start);
390 first = XINT (start);
391 CHECK_INT_COERCE_CHAR (end);
394 signal_simple_error_2 ("start must be <= end", start, end);
396 put_range_table (table, first, last, val);
397 verify_range_table (XRANGE_TABLE (table));
401 DEFUN ("remove-range-table", Fremove_range_table, 3, 3, 0, /*
402 Remove the value for range (START, END) in TABLE.
406 return Fput_range_table (start, end, Qunbound, table);
409 DEFUN ("clear-range-table", Fclear_range_table, 1, 1, 0, /*
414 CHECK_RANGE_TABLE (table);
415 Dynarr_reset (XRANGE_TABLE (table)->entries);
419 DEFUN ("map-range-table", Fmap_range_table, 2, 2, 0, /*
420 Map FUNCTION over entries in TABLE, calling it with three args,
421 the beginning and end of the range and the corresponding value.
425 error ("not yet implemented");
430 /************************************************************************/
431 /* Range table read syntax */
432 /************************************************************************/
435 rangetab_data_validate (Lisp_Object keyword, Lisp_Object value,
440 /* #### should deal with errb */
441 EXTERNAL_LIST_LOOP (rest, value)
443 Lisp_Object range = XCAR (rest);
446 signal_simple_error ("Invalid list format", value);
447 if (!INTP (range) && !CHARP (range)
448 && !(CONSP (range) && CONSP (XCDR (range))
449 && NILP (XCDR (XCDR (range)))
450 && (INTP (XCAR (range)) || CHARP (XCAR (range)))
451 && (INTP (XCAR (XCDR (range))) || CHARP (XCAR (XCDR (range))))))
452 signal_simple_error ("Invalid range format", range);
459 rangetab_instantiate (Lisp_Object data)
461 Lisp_Object rangetab = Fmake_range_table ();
465 data = Fcar (Fcdr (data)); /* skip over 'data keyword */
468 Lisp_Object range = Fcar (data);
469 Lisp_Object val = Fcar (Fcdr (data));
471 data = Fcdr (Fcdr (data));
473 Fput_range_table (Fcar (range), Fcar (Fcdr (range)), val,
476 Fput_range_table (range, range, val, rangetab);
484 /************************************************************************/
485 /* Unified range tables */
486 /************************************************************************/
488 /* A "unified range table" is a format for storing range tables
489 as contiguous blocks of memory. This is used by the regexp
490 code, which needs to use range tables to properly handle []
491 constructs in the presence of extended characters but wants to
492 store an entire compiled pattern as a contiguous block of memory.
494 Unified range tables are designed so that they can be placed
495 at an arbitrary (possibly mis-aligned) place in memory.
496 (Dealing with alignment is a pain in the ass.)
498 WARNING: No provisions for garbage collection are currently made.
499 This means that there must not be any Lisp objects in a unified
500 range table that need to be marked for garbage collection.
501 Good candidates for objects that can go into a range table are
503 -- numbers and characters (do not need to be marked)
504 -- nil, t (marked elsewhere)
505 -- charsets and coding systems (automatically marked because
506 they are in a marked list,
507 and can't be removed)
509 Good but slightly less so:
511 -- symbols (could be uninterned, but that is not likely)
515 -- buffers, frames, devices (could get deleted)
518 It is expected that you work with range tables in the normal
519 format and then convert to unified format when you are done
520 making modifications. As such, no functions are provided
521 for modifying a unified range table. The only operations
522 you can do to unified range tables are
525 -- retrieve all the ranges in an iterative fashion
529 /* The format of a unified range table is as follows:
531 -- The first byte contains the number of bytes to skip to find the
532 actual start of the table. This deals with alignment constraints,
533 since the table might want to go at any arbitrary place in memory.
534 -- The next three bytes contain the number of bytes to skip (from the
535 *first* byte) to find the stuff after the table. It's stored in
536 little-endian format because that's how God intended things. We don't
537 necessarily start the stuff at the very end of the table because
538 we want to have at least ALIGNOF (EMACS_INT) extra space in case
539 we have to move the range table around. (It appears that some
540 architectures don't maintain alignment when reallocing.)
541 -- At the prescribed offset is a struct unified_range_table, containing
542 some number of `struct range_table_entry' entries. */
544 struct unified_range_table
547 struct range_table_entry first;
550 /* Return size in bytes needed to store the data in a range table. */
553 unified_range_table_bytes_needed (Lisp_Object rangetab)
555 return (sizeof (struct range_table_entry) *
556 (Dynarr_length (XRANGE_TABLE (rangetab)->entries) - 1) +
557 sizeof (struct unified_range_table) +
558 /* ALIGNOF a struct may be too big. */
559 /* We have four bytes for the size numbers, and an extra
560 four or eight bytes for making sure we get the alignment
562 ALIGNOF (EMACS_INT) + 4);
565 /* Convert a range table into unified format and store in DEST,
566 which must be able to hold the number of bytes returned by
567 range_table_bytes_needed(). */
570 unified_range_table_copy_data (Lisp_Object rangetab, void *dest)
572 /* We cast to the above structure rather than just casting to
573 char * and adding sizeof(int), because that will lead to
574 mis-aligned data on the Alpha machines. */
575 struct unified_range_table *un;
576 range_table_entry_dynarr *rted = XRANGE_TABLE (rangetab)->entries;
577 int total_needed = unified_range_table_bytes_needed (rangetab);
578 void *new_dest = ALIGN_PTR ((char *) dest + 4, ALIGNOF (EMACS_INT));
580 * (char *) dest = (char) ((char *) new_dest - (char *) dest);
581 * ((unsigned char *) dest + 1) = total_needed & 0xFF;
583 * ((unsigned char *) dest + 2) = total_needed & 0xFF;
585 * ((unsigned char *) dest + 3) = total_needed & 0xFF;
586 un = (struct unified_range_table *) new_dest;
587 un->nentries = Dynarr_length (rted);
588 memcpy (&un->first, Dynarr_atp (rted, 0),
589 sizeof (struct range_table_entry) * Dynarr_length (rted));
592 /* Return number of bytes actually used by a unified range table. */
595 unified_range_table_bytes_used (void *unrangetab)
597 return ((* ((unsigned char *) unrangetab + 1))
598 + ((* ((unsigned char *) unrangetab + 2)) << 8)
599 + ((* ((unsigned char *) unrangetab + 3)) << 16));
602 /* Make sure the table is aligned, and move it around if it's not. */
604 align_the_damn_table (void *unrangetab)
606 void *cur_dest = (char *) unrangetab + * (char *) unrangetab;
608 if ((((long) cur_dest) & 7) != 0)
610 if ((((int) cur_dest) & 3) != 0)
613 int count = (unified_range_table_bytes_used (unrangetab) - 4
614 - ALIGNOF (EMACS_INT));
615 /* Find the proper location, just like above. */
616 void *new_dest = ALIGN_PTR ((char *) unrangetab + 4,
617 ALIGNOF (EMACS_INT));
618 /* memmove() works in the presence of overlapping data. */
619 memmove (new_dest, cur_dest, count);
620 * (char *) unrangetab = (char) ((char *) new_dest - (char *) unrangetab);
624 /* Look up a value in a unified range table. */
627 unified_range_table_lookup (void *unrangetab, EMACS_INT pos,
628 Lisp_Object default_)
631 struct unified_range_table *un;
633 align_the_damn_table (unrangetab);
634 new_dest = (char *) unrangetab + * (char *) unrangetab;
635 un = (struct unified_range_table *) new_dest;
637 return get_range_table (pos, un->nentries, &un->first, default_);
640 /* Return number of entries in a unified range table. */
643 unified_range_table_nentries (void *unrangetab)
646 struct unified_range_table *un;
648 align_the_damn_table (unrangetab);
649 new_dest = (char *) unrangetab + * (char *) unrangetab;
650 un = (struct unified_range_table *) new_dest;
654 /* Return the OFFSETth range (counting from 0) in UNRANGETAB. */
656 unified_range_table_get_range (void *unrangetab, int offset,
657 EMACS_INT *min, EMACS_INT *max,
661 struct unified_range_table *un;
662 struct range_table_entry *tab;
664 align_the_damn_table (unrangetab);
665 new_dest = (char *) unrangetab + * (char *) unrangetab;
666 un = (struct unified_range_table *) new_dest;
668 assert (offset >= 0 && offset < un->nentries);
669 tab = (&un->first) + offset;
676 /************************************************************************/
678 /************************************************************************/
681 syms_of_rangetab (void)
683 defsymbol (&Qrange_tablep, "range-table-p");
684 defsymbol (&Qrange_table, "range-table");
686 DEFSUBR (Frange_table_p);
687 DEFSUBR (Fmake_range_table);
688 DEFSUBR (Fcopy_range_table);
689 DEFSUBR (Fget_range_table);
690 DEFSUBR (Fput_range_table);
691 DEFSUBR (Fremove_range_table);
692 DEFSUBR (Fclear_range_table);
693 DEFSUBR (Fmap_range_table);
697 structure_type_create_rangetab (void)
699 struct structure_type *st;
701 st = define_structure_type (Qrange_table, 0, rangetab_instantiate);
703 define_structure_type_keyword (st, Qdata, rangetab_data_validate);