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a50699fd JA |
1 | /* Code for doing intervals. |
2 | Copyright (C) 1991, 1992 Free Software Foundation, Inc. | |
3 | ||
4 | This file is part of GNU Emacs. | |
5 | ||
6 | GNU Emacs is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 1, or (at your option) | |
9 | any later version. | |
10 | ||
11 | GNU Emacs is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with GNU Emacs; see the file COPYING. If not, write to | |
18 | the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
19 | ||
20 | ||
21 | /* NOTES: | |
22 | ||
23 | Have to ensure that we can't put symbol nil on a plist, or some | |
24 | functions may work incorrectly. | |
25 | ||
26 | An idea: Have the owner of the tree keep count of splits and/or | |
27 | insertion lengths (in intervals), and balance after every N. | |
28 | ||
29 | Need to call *_left_hook when buffer is killed. | |
30 | ||
31 | Scan for zero-length, or 0-length to see notes about handling | |
32 | zero length interval-markers. | |
33 | ||
34 | There are comments around about freeing intervals. It might be | |
35 | faster to explicitly free them (put them on the free list) than | |
36 | to GC them. | |
37 | ||
38 | */ | |
39 | ||
40 | ||
41 | #include "config.h" | |
42 | #include "lisp.h" | |
43 | #include "intervals.h" | |
44 | #include "buffer.h" | |
a50699fd | 45 | |
d2f7a802 JA |
46 | /* The rest of the file is within this conditional. */ |
47 | #ifdef USE_TEXT_PROPERTIES | |
48 | ||
a50699fd JA |
49 | /* Factor for weight-balancing interval trees. */ |
50 | Lisp_Object interval_balance_threshold; | |
51 | \f | |
52 | /* Utility functions for intervals. */ | |
53 | ||
54 | ||
55 | /* Create the root interval of some object, a buffer or string. */ | |
56 | ||
57 | INTERVAL | |
58 | create_root_interval (parent) | |
59 | Lisp_Object parent; | |
60 | { | |
61 | INTERVAL new = make_interval (); | |
62 | ||
63 | if (XTYPE (parent) == Lisp_Buffer) | |
64 | { | |
65 | new->total_length = BUF_Z (XBUFFER (parent)) - 1; | |
66 | XBUFFER (parent)->intervals = new; | |
67 | } | |
68 | else if (XTYPE (parent) == Lisp_String) | |
69 | { | |
70 | new->total_length = XSTRING (parent)->size; | |
71 | XSTRING (parent)->intervals = new; | |
72 | } | |
73 | ||
74 | new->parent = (INTERVAL) parent; | |
75 | new->position = 1; | |
76 | ||
77 | return new; | |
78 | } | |
79 | ||
80 | /* Make the interval TARGET have exactly the properties of SOURCE */ | |
81 | ||
82 | void | |
83 | copy_properties (source, target) | |
84 | register INTERVAL source, target; | |
85 | { | |
86 | if (DEFAULT_INTERVAL_P (source) && DEFAULT_INTERVAL_P (target)) | |
87 | return; | |
88 | ||
89 | COPY_INTERVAL_CACHE (source, target); | |
90 | target->plist = Fcopy_sequence (source->plist); | |
91 | } | |
92 | ||
93 | /* Merge the properties of interval SOURCE into the properties | |
94 | of interval TARGET. */ | |
95 | ||
96 | static void | |
97 | merge_properties (source, target) | |
98 | register INTERVAL source, target; | |
99 | { | |
100 | register Lisp_Object o, sym, val; | |
101 | ||
102 | if (DEFAULT_INTERVAL_P (source) && DEFAULT_INTERVAL_P (target)) | |
103 | return; | |
104 | ||
105 | MERGE_INTERVAL_CACHE (source, target); | |
106 | ||
107 | o = source->plist; | |
108 | while (! EQ (o, Qnil)) | |
109 | { | |
110 | sym = Fcar (o); | |
111 | val = Fmemq (sym, target->plist); | |
112 | ||
113 | if (NILP (val)) | |
114 | { | |
115 | o = Fcdr (o); | |
116 | val = Fcar (o); | |
117 | target->plist = Fcons (sym, Fcons (val, target->plist)); | |
118 | o = Fcdr (o); | |
119 | } | |
120 | else | |
121 | o = Fcdr (Fcdr (o)); | |
122 | } | |
123 | } | |
124 | ||
125 | /* Return 1 if the two intervals have the same properties, | |
126 | 0 otherwise. */ | |
127 | ||
128 | int | |
129 | intervals_equal (i0, i1) | |
130 | INTERVAL i0, i1; | |
131 | { | |
132 | register Lisp_Object i0_cdr, i0_sym, i1_val; | |
133 | register i1_len; | |
134 | ||
135 | if (DEFAULT_INTERVAL_P (i0) && DEFAULT_INTERVAL_P (i1)) | |
136 | return 1; | |
137 | ||
138 | i1_len = XFASTINT (Flength (i1->plist)); | |
139 | if (i1_len & 0x1) /* Paranoia -- plists are always even */ | |
140 | abort (); | |
141 | i1_len /= 2; | |
142 | i0_cdr = i0->plist; | |
143 | while (!NILP (i0_cdr)) | |
144 | { | |
145 | /* Lengths of the two plists were unequal */ | |
146 | if (i1_len == 0) | |
147 | return 0; | |
148 | ||
149 | i0_sym = Fcar (i0_cdr); | |
150 | i1_val = Fmemq (i0_sym, i1->plist); | |
151 | ||
152 | /* i0 has something i1 doesn't */ | |
153 | if (EQ (i1_val, Qnil)) | |
154 | return 0; | |
155 | ||
156 | /* i0 and i1 both have sym, but it has different values in each */ | |
157 | i0_cdr = Fcdr (i0_cdr); | |
158 | if (! Fequal (i1_val, Fcar (i0_cdr))) | |
159 | return 0; | |
160 | ||
161 | i0_cdr = Fcdr (i0_cdr); | |
162 | i1_len--; | |
163 | } | |
164 | ||
165 | /* Lengths of the two plists were unequal */ | |
166 | if (i1_len > 0) | |
167 | return 0; | |
168 | ||
169 | return 1; | |
170 | } | |
171 | \f | |
172 | static int icount; | |
173 | static int idepth; | |
174 | static int zero_length; | |
175 | ||
a50699fd JA |
176 | /* Traverse an interval tree TREE, performing FUNCTION on each node. |
177 | ||
178 | Perhaps we should pass the depth as an argument. */ | |
179 | ||
180 | void | |
e0b63493 | 181 | traverse_intervals (tree, position, depth, function) |
a50699fd | 182 | INTERVAL tree; |
e0b63493 | 183 | int position, depth; |
a50699fd JA |
184 | void (* function) (); |
185 | { | |
186 | if (NULL_INTERVAL_P (tree)) | |
187 | return; | |
188 | ||
e0b63493 | 189 | traverse_intervals (tree->left, position, depth + 1, function); |
a50699fd JA |
190 | position += LEFT_TOTAL_LENGTH (tree); |
191 | tree->position = position; | |
192 | (*function) (tree); | |
193 | position += LENGTH (tree); | |
e0b63493 | 194 | traverse_intervals (tree->right, position, depth + 1, function); |
a50699fd JA |
195 | } |
196 | \f | |
197 | #if 0 | |
198 | /* These functions are temporary, for debugging purposes only. */ | |
199 | ||
200 | INTERVAL search_interval, found_interval; | |
201 | ||
202 | void | |
203 | check_for_interval (i) | |
204 | register INTERVAL i; | |
205 | { | |
206 | if (i == search_interval) | |
207 | { | |
208 | found_interval = i; | |
209 | icount++; | |
210 | } | |
211 | } | |
212 | ||
213 | INTERVAL | |
214 | search_for_interval (i, tree) | |
215 | register INTERVAL i, tree; | |
216 | { | |
217 | icount = 0; | |
218 | search_interval = i; | |
219 | found_interval = NULL_INTERVAL; | |
e0b63493 | 220 | traverse_intervals (tree, 1, 0, &check_for_interval); |
a50699fd JA |
221 | return found_interval; |
222 | } | |
223 | ||
224 | static void | |
225 | inc_interval_count (i) | |
226 | INTERVAL i; | |
227 | { | |
228 | icount++; | |
229 | if (LENGTH (i) == 0) | |
230 | zero_length++; | |
231 | if (depth > idepth) | |
232 | idepth = depth; | |
233 | } | |
234 | ||
235 | int | |
236 | count_intervals (i) | |
237 | register INTERVAL i; | |
238 | { | |
239 | icount = 0; | |
240 | idepth = 0; | |
241 | zero_length = 0; | |
e0b63493 | 242 | traverse_intervals (i, 1, 0, &inc_interval_count); |
a50699fd JA |
243 | |
244 | return icount; | |
245 | } | |
246 | ||
247 | static INTERVAL | |
248 | root_interval (interval) | |
249 | INTERVAL interval; | |
250 | { | |
251 | register INTERVAL i = interval; | |
252 | ||
253 | while (! ROOT_INTERVAL_P (i)) | |
254 | i = i->parent; | |
255 | ||
256 | return i; | |
257 | } | |
258 | #endif | |
259 | \f | |
260 | /* Assuming that a left child exists, perform the following operation: | |
261 | ||
262 | A B | |
263 | / \ / \ | |
264 | B => A | |
265 | / \ / \ | |
266 | c c | |
267 | */ | |
268 | ||
269 | static INTERVAL | |
270 | rotate_right (interval) | |
271 | INTERVAL interval; | |
272 | { | |
273 | INTERVAL i; | |
274 | INTERVAL B = interval->left; | |
275 | int len = LENGTH (interval); | |
276 | ||
277 | /* Deal with any Parent of A; make it point to B. */ | |
278 | if (! ROOT_INTERVAL_P (interval)) | |
279 | if (AM_LEFT_CHILD (interval)) | |
280 | interval->parent->left = interval->left; | |
281 | else | |
282 | interval->parent->right = interval->left; | |
283 | interval->left->parent = interval->parent; | |
284 | ||
285 | /* B gets the same length as A, since it get A's position in the tree. */ | |
286 | interval->left->total_length = interval->total_length; | |
287 | ||
288 | /* B becomes the parent of A. */ | |
289 | i = interval->left->right; | |
290 | interval->left->right = interval; | |
291 | interval->parent = interval->left; | |
292 | ||
293 | /* A gets c as left child. */ | |
294 | interval->left = i; | |
295 | if (! NULL_INTERVAL_P (i)) | |
296 | i->parent = interval; | |
297 | interval->total_length = (len + LEFT_TOTAL_LENGTH (interval) | |
298 | + RIGHT_TOTAL_LENGTH (interval)); | |
299 | ||
300 | return B; | |
301 | } | |
302 | \f | |
303 | /* Assuming that a right child exists, perform the following operation: | |
304 | ||
305 | A B | |
306 | / \ / \ | |
307 | B => A | |
308 | / \ / \ | |
309 | c c | |
310 | */ | |
311 | ||
312 | static INTERVAL | |
313 | rotate_left (interval) | |
314 | INTERVAL interval; | |
315 | { | |
316 | INTERVAL i; | |
317 | INTERVAL B = interval->right; | |
318 | int len = LENGTH (interval); | |
319 | ||
320 | /* Deal with the parent of A. */ | |
321 | if (! ROOT_INTERVAL_P (interval)) | |
322 | if (AM_LEFT_CHILD (interval)) | |
323 | interval->parent->left = interval->right; | |
324 | else | |
325 | interval->parent->right = interval->right; | |
326 | interval->right->parent = interval->parent; | |
327 | ||
328 | /* B must have the same total length of A. */ | |
329 | interval->right->total_length = interval->total_length; | |
330 | ||
331 | /* Make B the parent of A */ | |
332 | i = interval->right->left; | |
333 | interval->right->left = interval; | |
334 | interval->parent = interval->right; | |
335 | ||
336 | /* Make A point to c */ | |
337 | interval->right = i; | |
338 | if (! NULL_INTERVAL_P (i)) | |
339 | i->parent = interval; | |
340 | interval->total_length = (len + LEFT_TOTAL_LENGTH (interval) | |
341 | + RIGHT_TOTAL_LENGTH (interval)); | |
342 | ||
343 | return B; | |
344 | } | |
345 | \f | |
90ba40fc JA |
346 | /* Split INTERVAL into two pieces, starting the second piece at character |
347 | position OFFSET (counting from 1), relative to INTERVAL. The right-hand | |
348 | piece (second, lexicographically) is returned. | |
349 | ||
350 | The size and position fields of the two intervals are set based upon | |
351 | those of the original interval. The property list of the new interval | |
352 | is reset, thus it is up to the caller to do the right thing with the | |
353 | result. | |
a50699fd JA |
354 | |
355 | Note that this does not change the position of INTERVAL; if it is a root, | |
356 | it is still a root after this operation. */ | |
357 | ||
358 | INTERVAL | |
90ba40fc | 359 | split_interval_right (interval, offset) |
a50699fd | 360 | INTERVAL interval; |
90ba40fc | 361 | int offset; |
a50699fd JA |
362 | { |
363 | INTERVAL new = make_interval (); | |
364 | int position = interval->position; | |
90ba40fc | 365 | int new_length = LENGTH (interval) - offset + 1; |
a50699fd | 366 | |
90ba40fc | 367 | new->position = position + offset - 1; |
a50699fd | 368 | new->parent = interval; |
a50699fd JA |
369 | |
370 | if (LEAF_INTERVAL_P (interval) || NULL_RIGHT_CHILD (interval)) | |
371 | { | |
372 | interval->right = new; | |
373 | new->total_length = new_length; | |
374 | ||
375 | return new; | |
376 | } | |
377 | ||
378 | /* Insert the new node between INTERVAL and its right child. */ | |
379 | new->right = interval->right; | |
380 | interval->right->parent = new; | |
381 | interval->right = new; | |
382 | ||
383 | new->total_length = new_length + new->right->total_length; | |
384 | ||
385 | return new; | |
386 | } | |
387 | ||
90ba40fc JA |
388 | /* Split INTERVAL into two pieces, starting the second piece at character |
389 | position OFFSET (counting from 1), relative to INTERVAL. The left-hand | |
390 | piece (first, lexicographically) is returned. | |
a50699fd | 391 | |
90ba40fc JA |
392 | The size and position fields of the two intervals are set based upon |
393 | those of the original interval. The property list of the new interval | |
394 | is reset, thus it is up to the caller to do the right thing with the | |
395 | result. | |
396 | ||
397 | Note that this does not change the position of INTERVAL; if it is a root, | |
398 | it is still a root after this operation. */ | |
a50699fd JA |
399 | |
400 | INTERVAL | |
90ba40fc | 401 | split_interval_left (interval, offset) |
a50699fd | 402 | INTERVAL interval; |
90ba40fc | 403 | int offset; |
a50699fd JA |
404 | { |
405 | INTERVAL new = make_interval (); | |
406 | int position = interval->position; | |
90ba40fc | 407 | int new_length = offset - 1; |
a50699fd | 408 | |
a50699fd | 409 | new->position = interval->position; |
90ba40fc | 410 | interval->position = interval->position + offset - 1; |
a50699fd JA |
411 | new->parent = interval; |
412 | ||
413 | if (NULL_LEFT_CHILD (interval)) | |
414 | { | |
415 | interval->left = new; | |
416 | new->total_length = new_length; | |
417 | ||
418 | return new; | |
419 | } | |
420 | ||
421 | /* Insert the new node between INTERVAL and its left child. */ | |
422 | new->left = interval->left; | |
423 | new->left->parent = new; | |
424 | interval->left = new; | |
425 | new->total_length = LENGTH (new) + LEFT_TOTAL_LENGTH (new); | |
426 | ||
427 | return new; | |
428 | } | |
429 | \f | |
90ba40fc JA |
430 | /* Find the interval containing text position POSITION in the text |
431 | represented by the interval tree TREE. POSITION is relative to | |
432 | the beginning of that text. | |
a50699fd | 433 | |
90ba40fc JA |
434 | The `position' field, which is a cache of an interval's position, |
435 | is updated in the interval found. Other functions (e.g., next_interval) | |
436 | will update this cache based on the result of find_interval. */ | |
437 | ||
438 | INLINE INTERVAL | |
a50699fd JA |
439 | find_interval (tree, position) |
440 | register INTERVAL tree; | |
441 | register int position; | |
442 | { | |
443 | register int relative_position = position; | |
444 | ||
445 | if (NULL_INTERVAL_P (tree)) | |
446 | return NULL_INTERVAL; | |
447 | ||
448 | if (position > TOTAL_LENGTH (tree)) | |
449 | abort (); /* Paranoia */ | |
450 | #if 0 | |
451 | position = TOTAL_LENGTH (tree); | |
452 | #endif | |
453 | ||
454 | while (1) | |
455 | { | |
456 | if (relative_position <= LEFT_TOTAL_LENGTH (tree)) | |
457 | { | |
458 | tree = tree->left; | |
459 | } | |
460 | else if (relative_position > (TOTAL_LENGTH (tree) | |
461 | - RIGHT_TOTAL_LENGTH (tree))) | |
462 | { | |
463 | relative_position -= (TOTAL_LENGTH (tree) | |
464 | - RIGHT_TOTAL_LENGTH (tree)); | |
465 | tree = tree->right; | |
466 | } | |
467 | else | |
468 | { | |
469 | tree->position = LEFT_TOTAL_LENGTH (tree) | |
470 | + position - relative_position + 1; | |
471 | return tree; | |
472 | } | |
473 | } | |
474 | } | |
475 | \f | |
476 | /* Find the succeeding interval (lexicographically) to INTERVAL. | |
90ba40fc JA |
477 | Sets the `position' field based on that of INTERVAL (see |
478 | find_interval). */ | |
a50699fd JA |
479 | |
480 | INTERVAL | |
481 | next_interval (interval) | |
482 | register INTERVAL interval; | |
483 | { | |
484 | register INTERVAL i = interval; | |
485 | register int next_position; | |
486 | ||
487 | if (NULL_INTERVAL_P (i)) | |
488 | return NULL_INTERVAL; | |
489 | next_position = interval->position + LENGTH (interval); | |
490 | ||
491 | if (! NULL_RIGHT_CHILD (i)) | |
492 | { | |
493 | i = i->right; | |
494 | while (! NULL_LEFT_CHILD (i)) | |
495 | i = i->left; | |
496 | ||
497 | i->position = next_position; | |
498 | return i; | |
499 | } | |
500 | ||
501 | while (! NULL_PARENT (i)) | |
502 | { | |
503 | if (AM_LEFT_CHILD (i)) | |
504 | { | |
505 | i = i->parent; | |
506 | i->position = next_position; | |
507 | return i; | |
508 | } | |
509 | ||
510 | i = i->parent; | |
511 | } | |
512 | ||
513 | return NULL_INTERVAL; | |
514 | } | |
515 | ||
516 | /* Find the preceding interval (lexicographically) to INTERVAL. | |
90ba40fc JA |
517 | Sets the `position' field based on that of INTERVAL (see |
518 | find_interval). */ | |
a50699fd JA |
519 | |
520 | INTERVAL | |
521 | previous_interval (interval) | |
522 | register INTERVAL interval; | |
523 | { | |
524 | register INTERVAL i; | |
525 | register position_of_previous; | |
526 | ||
527 | if (NULL_INTERVAL_P (interval)) | |
528 | return NULL_INTERVAL; | |
529 | ||
530 | if (! NULL_LEFT_CHILD (interval)) | |
531 | { | |
532 | i = interval->left; | |
533 | while (! NULL_RIGHT_CHILD (i)) | |
534 | i = i->right; | |
535 | ||
536 | i->position = interval->position - LENGTH (i); | |
537 | return i; | |
538 | } | |
539 | ||
540 | i = interval; | |
541 | while (! NULL_PARENT (i)) | |
542 | { | |
543 | if (AM_RIGHT_CHILD (i)) | |
544 | { | |
545 | i = i->parent; | |
546 | ||
547 | i->position = interval->position - LENGTH (i); | |
548 | return i; | |
549 | } | |
550 | i = i->parent; | |
551 | } | |
552 | ||
553 | return NULL_INTERVAL; | |
554 | } | |
555 | \f | |
90ba40fc | 556 | #if 0 |
a50699fd JA |
557 | /* Traverse a path down the interval tree TREE to the interval |
558 | containing POSITION, adjusting all nodes on the path for | |
559 | an addition of LENGTH characters. Insertion between two intervals | |
560 | (i.e., point == i->position, where i is second interval) means | |
561 | text goes into second interval. | |
562 | ||
563 | Modifications are needed to handle the hungry bits -- after simply | |
564 | finding the interval at position (don't add length going down), | |
565 | if it's the beginning of the interval, get the previous interval | |
566 | and check the hugry bits of both. Then add the length going back up | |
567 | to the root. */ | |
568 | ||
569 | static INTERVAL | |
570 | adjust_intervals_for_insertion (tree, position, length) | |
571 | INTERVAL tree; | |
572 | int position, length; | |
573 | { | |
574 | register int relative_position; | |
575 | register INTERVAL this; | |
576 | ||
577 | if (TOTAL_LENGTH (tree) == 0) /* Paranoia */ | |
578 | abort (); | |
579 | ||
580 | /* If inserting at point-max of a buffer, that position | |
581 | will be out of range */ | |
582 | if (position > TOTAL_LENGTH (tree)) | |
583 | position = TOTAL_LENGTH (tree); | |
584 | relative_position = position; | |
585 | this = tree; | |
586 | ||
587 | while (1) | |
588 | { | |
589 | if (relative_position <= LEFT_TOTAL_LENGTH (this)) | |
590 | { | |
591 | this->total_length += length; | |
592 | this = this->left; | |
593 | } | |
594 | else if (relative_position > (TOTAL_LENGTH (this) | |
595 | - RIGHT_TOTAL_LENGTH (this))) | |
596 | { | |
597 | relative_position -= (TOTAL_LENGTH (this) | |
598 | - RIGHT_TOTAL_LENGTH (this)); | |
599 | this->total_length += length; | |
600 | this = this->right; | |
601 | } | |
602 | else | |
603 | { | |
604 | /* If we are to use zero-length intervals as buffer pointers, | |
605 | then this code will have to change. */ | |
606 | this->total_length += length; | |
607 | this->position = LEFT_TOTAL_LENGTH (this) | |
608 | + position - relative_position + 1; | |
609 | return tree; | |
610 | } | |
611 | } | |
612 | } | |
90ba40fc JA |
613 | #endif |
614 | ||
615 | /* Effect an adjustment corresponding to the addition of LENGTH characters | |
616 | of text. Do this by finding the interval containing POSITION in the | |
617 | interval tree TREE, and then adjusting all of it's ancestors by adding | |
618 | LENGTH to them. | |
619 | ||
620 | If POSITION is the first character of an interval, meaning that point | |
621 | is actually between the two intervals, make the new text belong to | |
622 | the interval which is "sticky". | |
623 | ||
1d1d7ba0 | 624 | If both intervals are "sticky", then make them belong to the left-most |
90ba40fc JA |
625 | interval. Another possibility would be to create a new interval for |
626 | this text, and make it have the merged properties of both ends. */ | |
627 | ||
628 | static INTERVAL | |
629 | adjust_intervals_for_insertion (tree, position, length) | |
630 | INTERVAL tree; | |
631 | int position, length; | |
632 | { | |
633 | register INTERVAL i; | |
634 | ||
635 | if (TOTAL_LENGTH (tree) == 0) /* Paranoia */ | |
636 | abort (); | |
637 | ||
638 | /* If inserting at point-max of a buffer, that position | |
639 | will be out of range. */ | |
640 | if (position > TOTAL_LENGTH (tree)) | |
641 | position = TOTAL_LENGTH (tree); | |
642 | ||
643 | i = find_interval (tree, position); | |
644 | /* If we are positioned between intervals, check the stickiness of | |
645 | both of them. */ | |
646 | if (position == i->position | |
647 | && position != 1) | |
648 | { | |
249a6da9 | 649 | register INTERVAL prev = previous_interval (i); |
90ba40fc JA |
650 | |
651 | /* If both intervals are sticky here, then default to the | |
652 | left-most one. But perhaps we should create a new | |
653 | interval here instead... */ | |
7b1d5b85 | 654 | if (END_STICKY_P (prev)) |
90ba40fc JA |
655 | i = prev; |
656 | } | |
657 | ||
658 | while (! NULL_INTERVAL_P (i)) | |
659 | { | |
660 | i->total_length += length; | |
249a6da9 | 661 | i = i->parent; |
90ba40fc JA |
662 | } |
663 | ||
664 | return tree; | |
665 | } | |
a50699fd | 666 | \f |
90ba40fc JA |
667 | /* Delete an node I from its interval tree by merging its subtrees |
668 | into one subtree which is then returned. Caller is responsible for | |
a50699fd JA |
669 | storing the resulting subtree into its parent. */ |
670 | ||
671 | static INTERVAL | |
672 | delete_node (i) | |
673 | register INTERVAL i; | |
674 | { | |
675 | register INTERVAL migrate, this; | |
676 | register int migrate_amt; | |
677 | ||
678 | if (NULL_INTERVAL_P (i->left)) | |
679 | return i->right; | |
680 | if (NULL_INTERVAL_P (i->right)) | |
681 | return i->left; | |
682 | ||
683 | migrate = i->left; | |
684 | migrate_amt = i->left->total_length; | |
685 | this = i->right; | |
686 | this->total_length += migrate_amt; | |
687 | while (! NULL_INTERVAL_P (this->left)) | |
688 | { | |
689 | this = this->left; | |
690 | this->total_length += migrate_amt; | |
691 | } | |
692 | this->left = migrate; | |
693 | migrate->parent = this; | |
694 | ||
695 | return i->right; | |
696 | } | |
697 | ||
698 | /* Delete interval I from its tree by calling `delete_node' | |
699 | and properly connecting the resultant subtree. | |
700 | ||
701 | I is presumed to be empty; that is, no adjustments are made | |
702 | for the length of I. */ | |
703 | ||
704 | void | |
705 | delete_interval (i) | |
706 | register INTERVAL i; | |
707 | { | |
708 | register INTERVAL parent; | |
709 | int amt = LENGTH (i); | |
710 | ||
711 | if (amt > 0) /* Only used on zero-length intervals now. */ | |
712 | abort (); | |
713 | ||
714 | if (ROOT_INTERVAL_P (i)) | |
715 | { | |
716 | Lisp_Object owner = (Lisp_Object) i->parent; | |
717 | parent = delete_node (i); | |
718 | if (! NULL_INTERVAL_P (parent)) | |
719 | parent->parent = (INTERVAL) owner; | |
720 | ||
721 | if (XTYPE (owner) == Lisp_Buffer) | |
722 | XBUFFER (owner)->intervals = parent; | |
723 | else if (XTYPE (owner) == Lisp_String) | |
724 | XSTRING (owner)->intervals = parent; | |
725 | else | |
726 | abort (); | |
727 | ||
728 | return; | |
729 | } | |
730 | ||
731 | parent = i->parent; | |
732 | if (AM_LEFT_CHILD (i)) | |
733 | { | |
734 | parent->left = delete_node (i); | |
735 | if (! NULL_INTERVAL_P (parent->left)) | |
736 | parent->left->parent = parent; | |
737 | } | |
738 | else | |
739 | { | |
740 | parent->right = delete_node (i); | |
741 | if (! NULL_INTERVAL_P (parent->right)) | |
742 | parent->right->parent = parent; | |
743 | } | |
744 | } | |
745 | \f | |
1d1d7ba0 JA |
746 | /* Find the interval in TREE corresponding to the character position FROM |
747 | and delete as much as possible of AMOUNT from that interval, starting | |
748 | after the relative position of FROM within it. Return the amount | |
749 | actually deleted, and if the interval was zeroed-out, delete that | |
750 | interval node from the tree. | |
a50699fd | 751 | |
1d1d7ba0 JA |
752 | Do this by recursing down TREE to the interval in question, and |
753 | deleting the appropriate amount of text. */ | |
a50699fd JA |
754 | |
755 | static int | |
756 | interval_deletion_adjustment (tree, from, amount) | |
757 | register INTERVAL tree; | |
758 | register int from, amount; | |
759 | { | |
760 | register int relative_position = from; | |
761 | ||
762 | if (NULL_INTERVAL_P (tree)) | |
763 | return 0; | |
764 | ||
765 | /* Left branch */ | |
766 | if (relative_position <= LEFT_TOTAL_LENGTH (tree)) | |
767 | { | |
768 | int subtract = interval_deletion_adjustment (tree->left, | |
769 | relative_position, | |
770 | amount); | |
771 | tree->total_length -= subtract; | |
772 | return subtract; | |
773 | } | |
774 | /* Right branch */ | |
775 | else if (relative_position > (TOTAL_LENGTH (tree) | |
776 | - RIGHT_TOTAL_LENGTH (tree))) | |
777 | { | |
778 | int subtract; | |
779 | ||
780 | relative_position -= (tree->total_length | |
781 | - RIGHT_TOTAL_LENGTH (tree)); | |
782 | subtract = interval_deletion_adjustment (tree->right, | |
783 | relative_position, | |
784 | amount); | |
785 | tree->total_length -= subtract; | |
786 | return subtract; | |
787 | } | |
788 | /* Here -- this node */ | |
789 | else | |
790 | { | |
791 | /* If this is a zero-length, marker interval, then | |
792 | we must skip it. */ | |
793 | ||
794 | if (relative_position == LEFT_TOTAL_LENGTH (tree) + 1) | |
795 | { | |
796 | /* This means we're deleting from the beginning of this interval. */ | |
797 | register int my_amount = LENGTH (tree); | |
798 | ||
799 | if (amount < my_amount) | |
800 | { | |
801 | tree->total_length -= amount; | |
802 | return amount; | |
803 | } | |
804 | else | |
805 | { | |
806 | tree->total_length -= my_amount; | |
807 | if (LENGTH (tree) != 0) | |
808 | abort (); /* Paranoia */ | |
809 | ||
810 | delete_interval (tree); | |
811 | return my_amount; | |
812 | } | |
813 | } | |
814 | else /* Deleting starting in the middle. */ | |
815 | { | |
816 | register int my_amount = ((tree->total_length | |
817 | - RIGHT_TOTAL_LENGTH (tree)) | |
818 | - relative_position + 1); | |
819 | ||
820 | if (amount <= my_amount) | |
821 | { | |
822 | tree->total_length -= amount; | |
823 | return amount; | |
824 | } | |
825 | else | |
826 | { | |
827 | tree->total_length -= my_amount; | |
828 | return my_amount; | |
829 | } | |
830 | } | |
831 | } | |
832 | ||
1d1d7ba0 | 833 | /* Never reach here */ |
a50699fd JA |
834 | abort (); |
835 | } | |
836 | ||
1d1d7ba0 JA |
837 | /* Effect the adjustments neccessary to the interval tree of BUFFER |
838 | to correspond to the deletion of LENGTH characters from that buffer | |
839 | text. The deletion is effected at position START (relative to the | |
840 | buffer). */ | |
841 | ||
a50699fd JA |
842 | static void |
843 | adjust_intervals_for_deletion (buffer, start, length) | |
844 | struct buffer *buffer; | |
845 | int start, length; | |
846 | { | |
847 | register int left_to_delete = length; | |
848 | register INTERVAL tree = buffer->intervals; | |
849 | register int deleted; | |
850 | ||
851 | if (NULL_INTERVAL_P (tree)) | |
852 | return; | |
853 | ||
854 | if (length == TOTAL_LENGTH (tree)) | |
855 | { | |
856 | buffer->intervals = NULL_INTERVAL; | |
857 | return; | |
858 | } | |
859 | ||
860 | if (ONLY_INTERVAL_P (tree)) | |
861 | { | |
862 | tree->total_length -= length; | |
863 | return; | |
864 | } | |
865 | ||
866 | if (start > TOTAL_LENGTH (tree)) | |
867 | start = TOTAL_LENGTH (tree); | |
868 | while (left_to_delete > 0) | |
869 | { | |
870 | left_to_delete -= interval_deletion_adjustment (tree, start, | |
871 | left_to_delete); | |
872 | tree = buffer->intervals; | |
873 | if (left_to_delete == tree->total_length) | |
874 | { | |
875 | buffer->intervals = NULL_INTERVAL; | |
876 | return; | |
877 | } | |
878 | } | |
879 | } | |
880 | \f | |
1d1d7ba0 JA |
881 | /* Make the adjustments neccessary to the interval tree of BUFFER to |
882 | represent an addition or deletion of LENGTH characters starting | |
883 | at position START. Addition or deletion is indicated by the sign | |
884 | of LENGTH. */ | |
a50699fd JA |
885 | |
886 | INLINE void | |
887 | offset_intervals (buffer, start, length) | |
888 | struct buffer *buffer; | |
889 | int start, length; | |
890 | { | |
891 | if (NULL_INTERVAL_P (buffer->intervals) || length == 0) | |
892 | return; | |
893 | ||
894 | if (length > 0) | |
895 | adjust_intervals_for_insertion (buffer->intervals, start, length); | |
896 | else | |
897 | adjust_intervals_for_deletion (buffer, start, -length); | |
898 | } | |
9c79dd1b JA |
899 | \f |
900 | /* Merge interval I with its lexicographic successor. The resulting | |
901 | interval is returned, and has the properties of the original | |
902 | successor. The properties of I are lost. I is removed from the | |
903 | interval tree. | |
904 | ||
905 | IMPORTANT: | |
906 | The caller must verify that this is not the last (rightmost) | |
907 | interval. */ | |
908 | ||
909 | INTERVAL | |
910 | merge_interval_right (i) | |
911 | register INTERVAL i; | |
912 | { | |
913 | register int absorb = LENGTH (i); | |
914 | register INTERVAL successor; | |
915 | ||
916 | /* Zero out this interval. */ | |
917 | i->total_length -= absorb; | |
918 | ||
919 | /* Find the succeeding interval. */ | |
920 | if (! NULL_RIGHT_CHILD (i)) /* It's below us. Add absorb | |
921 | as we descend. */ | |
922 | { | |
923 | successor = i->right; | |
924 | while (! NULL_LEFT_CHILD (successor)) | |
925 | { | |
926 | successor->total_length += absorb; | |
927 | successor = successor->left; | |
928 | } | |
929 | ||
930 | successor->total_length += absorb; | |
931 | delete_interval (i); | |
932 | return successor; | |
933 | } | |
934 | ||
935 | successor = i; | |
936 | while (! NULL_PARENT (successor)) /* It's above us. Subtract as | |
937 | we ascend. */ | |
938 | { | |
939 | if (AM_LEFT_CHILD (successor)) | |
940 | { | |
941 | successor = successor->parent; | |
942 | delete_interval (i); | |
943 | return successor; | |
944 | } | |
945 | ||
946 | successor = successor->parent; | |
947 | successor->total_length -= absorb; | |
948 | } | |
949 | ||
950 | /* This must be the rightmost or last interval and cannot | |
951 | be merged right. The caller should have known. */ | |
952 | abort (); | |
953 | } | |
954 | \f | |
955 | /* Merge interval I with its lexicographic predecessor. The resulting | |
956 | interval is returned, and has the properties of the original predecessor. | |
957 | The properties of I are lost. Interval node I is removed from the tree. | |
958 | ||
959 | IMPORTANT: | |
960 | The caller must verify that this is not the first (leftmost) interval. */ | |
961 | ||
962 | INTERVAL | |
963 | merge_interval_left (i) | |
964 | register INTERVAL i; | |
965 | { | |
966 | register int absorb = LENGTH (i); | |
967 | register INTERVAL predecessor; | |
968 | ||
969 | /* Zero out this interval. */ | |
970 | i->total_length -= absorb; | |
971 | ||
972 | /* Find the preceding interval. */ | |
973 | if (! NULL_LEFT_CHILD (i)) /* It's below us. Go down, | |
974 | adding ABSORB as we go. */ | |
975 | { | |
976 | predecessor = i->left; | |
977 | while (! NULL_RIGHT_CHILD (predecessor)) | |
978 | { | |
979 | predecessor->total_length += absorb; | |
980 | predecessor = predecessor->right; | |
981 | } | |
982 | ||
983 | predecessor->total_length += absorb; | |
984 | delete_interval (i); | |
985 | return predecessor; | |
986 | } | |
987 | ||
988 | predecessor = i; | |
989 | while (! NULL_PARENT (predecessor)) /* It's above us. Go up, | |
990 | subtracting ABSORB. */ | |
991 | { | |
992 | if (AM_RIGHT_CHILD (predecessor)) | |
993 | { | |
994 | predecessor = predecessor->parent; | |
995 | delete_interval (i); | |
996 | return predecessor; | |
997 | } | |
998 | ||
999 | predecessor = predecessor->parent; | |
1000 | predecessor->total_length -= absorb; | |
1001 | } | |
a50699fd | 1002 | |
9c79dd1b JA |
1003 | /* This must be the leftmost or first interval and cannot |
1004 | be merged left. The caller should have known. */ | |
1005 | abort (); | |
1006 | } | |
1007 | \f | |
1d1d7ba0 JA |
1008 | /* Make an exact copy of interval tree SOURCE which descends from |
1009 | PARENT. This is done by recursing through SOURCE, copying | |
1010 | the current interval and its properties, and then adjusting | |
1011 | the pointers of the copy. */ | |
1012 | ||
a50699fd JA |
1013 | static INTERVAL |
1014 | reproduce_tree (source, parent) | |
1015 | INTERVAL source, parent; | |
1016 | { | |
1017 | register INTERVAL t = make_interval (); | |
1018 | ||
1019 | bcopy (source, t, INTERVAL_SIZE); | |
1020 | copy_properties (source, t); | |
1021 | t->parent = parent; | |
1022 | if (! NULL_LEFT_CHILD (source)) | |
1023 | t->left = reproduce_tree (source->left, t); | |
1024 | if (! NULL_RIGHT_CHILD (source)) | |
1025 | t->right = reproduce_tree (source->right, t); | |
1026 | ||
1027 | return t; | |
1028 | } | |
1029 | ||
1d1d7ba0 JA |
1030 | /* Make a new interval of length LENGTH starting at START in the |
1031 | group of intervals INTERVALS, which is actually an interval tree. | |
1032 | Returns the new interval. | |
1033 | ||
1034 | Generate an error if the new positions would overlap an existing | |
1035 | interval. */ | |
1036 | ||
a50699fd JA |
1037 | static INTERVAL |
1038 | make_new_interval (intervals, start, length) | |
1039 | INTERVAL intervals; | |
1040 | int start, length; | |
1041 | { | |
1042 | INTERVAL slot; | |
1043 | ||
1044 | slot = find_interval (intervals, start); | |
1045 | if (start + length > slot->position + LENGTH (slot)) | |
1046 | error ("Interval would overlap"); | |
1047 | ||
1048 | if (start == slot->position && length == LENGTH (slot)) | |
1049 | return slot; | |
1050 | ||
1051 | if (slot->position == start) | |
1052 | { | |
1053 | /* New right node. */ | |
1054 | split_interval_right (slot, length + 1); | |
1055 | return slot; | |
1056 | } | |
1057 | ||
1058 | if (slot->position + LENGTH (slot) == start + length) | |
1059 | { | |
1060 | /* New left node. */ | |
1061 | split_interval_left (slot, LENGTH (slot) - length + 1); | |
1062 | return slot; | |
1063 | } | |
1064 | ||
1065 | /* Convert interval SLOT into three intervals. */ | |
1066 | split_interval_left (slot, start - slot->position + 1); | |
1067 | split_interval_right (slot, length + 1); | |
1068 | return slot; | |
1069 | } | |
1070 | ||
9c79dd1b | 1071 | /* Insert the intervals of SOURCE into BUFFER at POSITION. |
a50699fd JA |
1072 | |
1073 | This is used in insdel.c when inserting Lisp_Strings into | |
9c79dd1b | 1074 | the buffer. The text corresponding to SOURCE is already in |
a50699fd JA |
1075 | the buffer when this is called. The intervals of new tree are |
1076 | those belonging to the string being inserted; a copy is not made. | |
1077 | ||
1078 | If the inserted text had no intervals associated, this function | |
1079 | simply returns -- offset_intervals should handle placing the | |
90ba40fc | 1080 | text in the correct interval, depending on the sticky bits. |
a50699fd JA |
1081 | |
1082 | If the inserted text had properties (intervals), then there are two | |
1083 | cases -- either insertion happened in the middle of some interval, | |
1084 | or between two intervals. | |
1085 | ||
1086 | If the text goes into the middle of an interval, then new | |
1087 | intervals are created in the middle with only the properties of | |
1088 | the new text, *unless* the macro MERGE_INSERTIONS is true, in | |
1089 | which case the new text has the union of its properties and those | |
1090 | of the text into which it was inserted. | |
1091 | ||
1092 | If the text goes between two intervals, then if neither interval | |
90ba40fc JA |
1093 | had its appropriate sticky property set (front_sticky, rear_sticky), |
1094 | the new text has only its properties. If one of the sticky properties | |
a50699fd JA |
1095 | is set, then the new text "sticks" to that region and its properties |
1096 | depend on merging as above. If both the preceding and succeding | |
90ba40fc JA |
1097 | intervals to the new text are "sticky", then the new text retains |
1098 | only its properties, as if neither sticky property were set. Perhaps | |
a50699fd JA |
1099 | we should consider merging all three sets of properties onto the new |
1100 | text... */ | |
1101 | ||
1102 | void | |
9c79dd1b JA |
1103 | graft_intervals_into_buffer (source, position, buffer) |
1104 | INTERVAL source; | |
a50699fd | 1105 | int position; |
9c79dd1b | 1106 | struct buffer *buffer; |
a50699fd JA |
1107 | { |
1108 | register INTERVAL under, over, this; | |
9c79dd1b | 1109 | register INTERVAL tree = buffer->intervals; |
a50699fd JA |
1110 | |
1111 | /* If the new text has no properties, it becomes part of whatever | |
1112 | interval it was inserted into. */ | |
9c79dd1b | 1113 | if (NULL_INTERVAL_P (source)) |
a50699fd JA |
1114 | return; |
1115 | ||
1116 | /* Paranoia -- the text has already been added, so this buffer | |
1117 | should be of non-zero length. */ | |
1118 | if (TOTAL_LENGTH (tree) == 0) | |
1119 | abort (); | |
1120 | ||
1121 | if (NULL_INTERVAL_P (tree)) | |
1122 | { | |
1123 | /* The inserted text constitutes the whole buffer, so | |
1124 | simply copy over the interval structure. */ | |
249a6da9 | 1125 | if (BUF_Z (buffer) == TOTAL_LENGTH (source)) |
a50699fd | 1126 | { |
9c79dd1b | 1127 | buffer->intervals = reproduce_tree (source, tree->parent); |
a50699fd JA |
1128 | /* Explicitly free the old tree here. */ |
1129 | ||
1130 | return; | |
1131 | } | |
1132 | ||
1133 | /* Create an interval tree in which to place a copy | |
1134 | of the intervals of the inserted string. */ | |
1135 | { | |
249a6da9 JA |
1136 | Lisp_Object buf; |
1137 | XSET (buf, Lisp_Buffer, buffer); | |
a50699fd JA |
1138 | create_root_interval (buffer); |
1139 | } | |
1140 | } | |
1141 | else | |
9c79dd1b | 1142 | if (TOTAL_LENGTH (tree) == TOTAL_LENGTH (source)) |
a50699fd JA |
1143 | |
1144 | /* If the buffer contains only the new string, but | |
1145 | there was already some interval tree there, then it may be | |
1146 | some zero length intervals. Eventually, do something clever | |
1147 | about inserting properly. For now, just waste the old intervals. */ | |
1148 | { | |
9c79dd1b | 1149 | buffer->intervals = reproduce_tree (source, tree->parent); |
a50699fd JA |
1150 | /* Explicitly free the old tree here. */ |
1151 | ||
1152 | return; | |
1153 | } | |
1154 | ||
1155 | this = under = find_interval (tree, position); | |
1156 | if (NULL_INTERVAL_P (under)) /* Paranoia */ | |
1157 | abort (); | |
9c79dd1b | 1158 | over = find_interval (source, 1); |
a50699fd JA |
1159 | |
1160 | /* Insertion between intervals */ | |
1161 | if (position == under->position) | |
1162 | { | |
1163 | /* First interval -- none precede it. */ | |
1164 | if (position == 1) | |
1165 | { | |
7b1d5b85 | 1166 | if (! FRONT_STICKY_P (under)) |
a50699fd JA |
1167 | /* The inserted string keeps its own properties. */ |
1168 | while (! NULL_INTERVAL_P (over)) | |
1169 | { | |
1170 | position = LENGTH (over) + 1; | |
1171 | this = split_interval_left (this, position); | |
1172 | copy_properties (over, this); | |
1173 | over = next_interval (over); | |
1174 | } | |
1175 | else | |
9c79dd1b JA |
1176 | /* This string "sticks" to the first interval, `under', |
1177 | which means it gets those properties. */ | |
a50699fd JA |
1178 | while (! NULL_INTERVAL_P (over)) |
1179 | { | |
1180 | position = LENGTH (over) + 1; | |
1181 | this = split_interval_left (this, position); | |
1182 | copy_properties (under, this); | |
1183 | if (MERGE_INSERTIONS (under)) | |
1184 | merge_properties (over, this); | |
1185 | over = next_interval (over); | |
1186 | } | |
1187 | } | |
1188 | else | |
1189 | { | |
1190 | INTERVAL prev = previous_interval (under); | |
1191 | if (NULL_INTERVAL_P (prev)) | |
1192 | abort (); | |
1193 | ||
7b1d5b85 | 1194 | if (END_STICKY_P (prev)) |
a50699fd | 1195 | { |
7b1d5b85 | 1196 | if (FRONT_STICKY_P (under)) |
90ba40fc | 1197 | /* The intervals go inbetween as the two sticky |
a50699fd JA |
1198 | properties cancel each other. Should we change |
1199 | this policy? */ | |
1200 | while (! NULL_INTERVAL_P (over)) | |
1201 | { | |
1202 | position = LENGTH (over) + 1; | |
1203 | this = split_interval_left (this, position); | |
1204 | copy_properties (over, this); | |
1205 | over = next_interval (over); | |
1206 | } | |
1207 | else | |
1208 | /* The intervals stick to prev */ | |
1209 | while (! NULL_INTERVAL_P (over)) | |
1210 | { | |
1211 | position = LENGTH (over) + 1; | |
1212 | this = split_interval_left (this, position); | |
1213 | copy_properties (prev, this); | |
1214 | if (MERGE_INSERTIONS (prev)) | |
1215 | merge_properties (over, this); | |
1216 | over = next_interval (over); | |
1217 | } | |
1218 | } | |
1219 | else | |
1220 | { | |
7b1d5b85 | 1221 | if (FRONT_STICKY_P (under)) |
9c79dd1b JA |
1222 | /* The inserted text "sticks" to the interval `under', |
1223 | which means it gets those properties. */ | |
a50699fd JA |
1224 | while (! NULL_INTERVAL_P (over)) |
1225 | { | |
1226 | position = LENGTH (over) + 1; | |
1227 | this = split_interval_left (this, position); | |
1228 | copy_properties (under, this); | |
1229 | if (MERGE_INSERTIONS (under)) | |
1230 | merge_properties (over, this); | |
1231 | over = next_interval (over); | |
1232 | } | |
1233 | else | |
1234 | /* The intervals go inbetween */ | |
1235 | while (! NULL_INTERVAL_P (over)) | |
1236 | { | |
1237 | position = LENGTH (over) + 1; | |
1238 | this = split_interval_left (this, position); | |
1239 | copy_properties (over, this); | |
1240 | over = next_interval (over); | |
1241 | } | |
1242 | } | |
1243 | } | |
1244 | ||
9c79dd1b | 1245 | buffer->intervals = balance_intervals (buffer->intervals); |
a50699fd JA |
1246 | return; |
1247 | } | |
1248 | ||
1249 | /* Here for insertion in the middle of an interval. */ | |
1250 | ||
9c79dd1b | 1251 | if (TOTAL_LENGTH (source) < LENGTH (this)) |
a50699fd JA |
1252 | { |
1253 | INTERVAL end_unchanged | |
9c79dd1b | 1254 | = split_interval_right (this, TOTAL_LENGTH (source) + 1); |
a50699fd JA |
1255 | copy_properties (under, end_unchanged); |
1256 | } | |
1257 | ||
1258 | position = position - tree->position + 1; | |
1259 | while (! NULL_INTERVAL_P (over)) | |
1260 | { | |
1261 | this = split_interval_right (under, position); | |
1262 | copy_properties (over, this); | |
1263 | if (MERGE_INSERTIONS (under)) | |
1264 | merge_properties (under, this); | |
1265 | ||
1266 | position = LENGTH (over) + 1; | |
1267 | over = next_interval (over); | |
1268 | } | |
1269 | ||
9c79dd1b | 1270 | buffer->intervals = balance_intervals (buffer->intervals); |
a50699fd JA |
1271 | return; |
1272 | } | |
1273 | ||
a50699fd JA |
1274 | /* Set point in BUFFER to POSITION. If the target position is in |
1275 | an invisible interval which is not displayed with a special glyph, | |
1276 | skip intervals until we find one. Point may be at the first | |
1277 | position of an invisible interval, if it is displayed with a | |
d7e3e52b | 1278 | special glyph. */ |
a50699fd JA |
1279 | |
1280 | void | |
1281 | set_point (position, buffer) | |
1282 | register int position; | |
1283 | register struct buffer *buffer; | |
1284 | { | |
1285 | register INTERVAL to, from, target; | |
1286 | register int iposition = position; | |
1287 | int buffer_point; | |
1288 | register Lisp_Object obj; | |
1289 | int backwards = (position < BUF_PT (buffer)) ? 1 : 0; | |
9c79dd1b | 1290 | int old_position = buffer->text.pt; |
a50699fd JA |
1291 | |
1292 | if (position == buffer->text.pt) | |
1293 | return; | |
1294 | ||
1295 | if (NULL_INTERVAL_P (buffer->intervals)) | |
1296 | { | |
1297 | buffer->text.pt = position; | |
1298 | return; | |
1299 | } | |
1300 | ||
1301 | /* Perhaps we should just change `position' to the limit. */ | |
1302 | if (position > BUF_Z (buffer) || position < BUF_BEG (buffer)) | |
1303 | abort (); | |
1304 | ||
1305 | /* Position Z is really one past the last char in the buffer. */ | |
1306 | if (position == BUF_Z (buffer)) | |
1307 | iposition = position - 1; | |
1308 | ||
1309 | to = find_interval (buffer->intervals, iposition); | |
1310 | buffer_point =(BUF_PT (buffer) == BUF_Z (buffer) | |
1311 | ? BUF_Z (buffer) - 1 | |
1312 | : BUF_PT (buffer)); | |
9c79dd1b JA |
1313 | |
1314 | /* We could cache this and save time. */ | |
a50699fd | 1315 | from = find_interval (buffer->intervals, buffer_point); |
9c79dd1b | 1316 | |
a50699fd JA |
1317 | if (NULL_INTERVAL_P (to) || NULL_INTERVAL_P (from)) |
1318 | abort (); /* Paranoia */ | |
1319 | ||
1320 | /* Moving within an interval */ | |
1321 | if (to == from && INTERVAL_VISIBLE_P (to)) | |
1322 | { | |
1323 | buffer->text.pt = position; | |
1324 | return; | |
1325 | } | |
1326 | ||
1327 | /* Here for the case of moving into another interval. */ | |
1328 | ||
1329 | target = to; | |
1330 | while (! INTERVAL_VISIBLE_P (to) && ! DISPLAY_INVISIBLE_GLYPH (to) | |
1331 | && ! NULL_INTERVAL_P (to)) | |
1332 | to = (backwards ? previous_interval (to) : next_interval (to)); | |
1333 | if (NULL_INTERVAL_P (to)) | |
1334 | return; | |
1335 | ||
1336 | /* Here we know we are actually moving to another interval. */ | |
1337 | if (INTERVAL_VISIBLE_P (to)) | |
1338 | { | |
1339 | /* If we skipped some intervals, go to the closest point | |
1340 | in the interval we've stopped at. */ | |
1341 | if (to != target) | |
1342 | buffer->text.pt = (backwards | |
1343 | ? to->position + LENGTH (to) - 1 | |
1344 | : to->position); | |
1345 | else | |
1346 | buffer->text.pt = position; | |
1347 | } | |
1348 | else | |
1349 | buffer->text.pt = to->position; | |
1350 | ||
d7e3e52b JA |
1351 | /* We run point-left and point-entered hooks here, iff the |
1352 | two intervals are not equivalent. These hooks take | |
1353 | (old_point, new_point) as arguments. */ | |
9c79dd1b JA |
1354 | if (! intervals_equal (from, to)) |
1355 | { | |
1356 | Lisp_Object val; | |
1357 | ||
1358 | val = Fget (Qpoint_left, from->plist); | |
1359 | if (! NILP (val)) | |
1360 | call2 (val, old_position, position); | |
1361 | ||
1362 | val = Fget (Qpoint_entered, to->plist); | |
1363 | if (! NILP (val)) | |
1364 | call2 (val, old_position, position); | |
1365 | } | |
a50699fd JA |
1366 | } |
1367 | ||
9c79dd1b | 1368 | /* Set point temporarily, without checking any text properties. */ |
a50699fd | 1369 | |
9c79dd1b JA |
1370 | INLINE void |
1371 | temp_set_point (position, buffer) | |
1372 | int position; | |
1373 | struct buffer *buffer; | |
1374 | { | |
1375 | buffer->text.pt = position; | |
1376 | } | |
1377 | ||
1378 | /* Check for read-only intervals and signal an error if we find one. | |
1379 | Then check for any modification hooks in the range START up to | |
1380 | (but not including) TO. Create a list of all these hooks in | |
1381 | lexicographic order, eliminating consecutive extra copies of the | |
1382 | same hook. Then call those hooks in order, with START and END - 1 | |
1383 | as arguments. */ | |
a50699fd JA |
1384 | |
1385 | void | |
1386 | verify_interval_modification (buf, start, end) | |
1387 | struct buffer *buf; | |
1388 | int start, end; | |
1389 | { | |
1390 | register INTERVAL intervals = buf->intervals; | |
1391 | register INTERVAL i; | |
249a6da9 | 1392 | Lisp_Object hooks = Qnil; |
9c79dd1b JA |
1393 | register prev_mod_hook = Qnil; |
1394 | register Lisp_Object mod_hook; | |
1395 | struct gcpro gcpro1; | |
a50699fd JA |
1396 | |
1397 | if (NULL_INTERVAL_P (intervals)) | |
1398 | return; | |
1399 | ||
1400 | if (start > end) | |
1401 | { | |
1402 | int temp = start; | |
1403 | start = end; | |
1404 | end = temp; | |
1405 | } | |
1406 | ||
1407 | if (start == BUF_Z (buf)) | |
1408 | { | |
9c79dd1b | 1409 | /* This should not be getting called on empty buffers. */ |
a50699fd JA |
1410 | if (BUF_Z (buf) == 1) |
1411 | abort (); | |
1412 | ||
1413 | i = find_interval (intervals, start - 1); | |
90ba40fc | 1414 | if (! END_STICKY_P (i)) |
a50699fd JA |
1415 | return; |
1416 | } | |
1417 | else | |
1418 | i = find_interval (intervals, start); | |
1419 | ||
1420 | do | |
1421 | { | |
a50699fd | 1422 | if (! INTERVAL_WRITABLE_P (i)) |
9c79dd1b JA |
1423 | error ("Attempt to modify read-only text"); |
1424 | ||
a50699fd | 1425 | mod_hook = Fget (Qmodification, i->plist); |
9c79dd1b JA |
1426 | if (! NILP (mod_hook) && ! EQ (mod_hook, prev_mod_hook)) |
1427 | { | |
1428 | hooks = Fcons (mod_hook, hooks); | |
1429 | prev_mod_hook = mod_hook; | |
1430 | } | |
1431 | ||
a50699fd JA |
1432 | i = next_interval (i); |
1433 | } | |
1434 | while (! NULL_INTERVAL_P (i) && i->position <= end); | |
1435 | ||
9c79dd1b | 1436 | GCPRO1 (hooks); |
a50699fd JA |
1437 | hooks = Fnreverse (hooks); |
1438 | while (! EQ (hooks, Qnil)) | |
9c79dd1b JA |
1439 | { |
1440 | call2 (Fcar (hooks), start, end - 1); | |
1441 | hooks = Fcdr (hooks); | |
1442 | } | |
1443 | UNGCPRO; | |
a50699fd JA |
1444 | } |
1445 | ||
1446 | /* Balance an interval node if the amount of text in its left and right | |
1447 | subtrees differs by more than the percentage specified by | |
1448 | `interval-balance-threshold'. */ | |
1449 | ||
1450 | static INTERVAL | |
1451 | balance_an_interval (i) | |
1452 | INTERVAL i; | |
1453 | { | |
1454 | register int total_children_size = (LEFT_TOTAL_LENGTH (i) | |
1455 | + RIGHT_TOTAL_LENGTH (i)); | |
1456 | register int threshold = (XFASTINT (interval_balance_threshold) | |
1457 | * (total_children_size / 100)); | |
1458 | ||
1459 | if (LEFT_TOTAL_LENGTH (i) > RIGHT_TOTAL_LENGTH (i) | |
1460 | && (LEFT_TOTAL_LENGTH (i) - RIGHT_TOTAL_LENGTH (i)) > threshold) | |
1461 | return rotate_right (i); | |
1462 | ||
1463 | if (LEFT_TOTAL_LENGTH (i) > RIGHT_TOTAL_LENGTH (i) | |
1464 | && (LEFT_TOTAL_LENGTH (i) - RIGHT_TOTAL_LENGTH (i)) > threshold) | |
1465 | return rotate_right (i); | |
1466 | ||
1467 | #if 0 | |
1468 | if (LEFT_TOTAL_LENGTH (i) > | |
1469 | (RIGHT_TOTAL_LENGTH (i) + XINT (interval_balance_threshold))) | |
1470 | return rotate_right (i); | |
1471 | ||
1472 | if (RIGHT_TOTAL_LENGTH (i) > | |
1473 | (LEFT_TOTAL_LENGTH (i) + XINT (interval_balance_threshold))) | |
1474 | return rotate_left (i); | |
1475 | #endif | |
1476 | ||
1477 | return i; | |
1478 | } | |
1479 | ||
1480 | /* Balance the interval tree TREE. Balancing is by weight | |
1481 | (the amount of text). */ | |
1482 | ||
1483 | INTERVAL | |
1484 | balance_intervals (tree) | |
1485 | register INTERVAL tree; | |
1486 | { | |
1487 | register INTERVAL new_tree; | |
1488 | ||
1489 | if (NULL_INTERVAL_P (tree)) | |
1490 | return NULL_INTERVAL; | |
1491 | ||
1492 | new_tree = tree; | |
1493 | do | |
1494 | { | |
1495 | tree = new_tree; | |
1496 | new_tree = balance_an_interval (new_tree); | |
1497 | } | |
1498 | while (new_tree != tree); | |
1499 | ||
1500 | return new_tree; | |
1501 | } | |
1502 | ||
9c79dd1b | 1503 | /* Produce an interval tree reflecting the intervals in |
a50699fd JA |
1504 | TREE from START to START + LENGTH. */ |
1505 | ||
7b1d5b85 | 1506 | INTERVAL |
a50699fd JA |
1507 | copy_intervals (tree, start, length) |
1508 | INTERVAL tree; | |
1509 | int start, length; | |
1510 | { | |
1511 | register INTERVAL i, new, t; | |
1512 | register int got; | |
1513 | ||
1514 | if (NULL_INTERVAL_P (tree) || length <= 0) | |
1515 | return NULL_INTERVAL; | |
1516 | ||
1517 | i = find_interval (tree, start); | |
1518 | if (NULL_INTERVAL_P (i) || LENGTH (i) == 0) | |
1519 | abort (); | |
1520 | ||
1521 | /* If there is only one interval and it's the default, return nil. */ | |
1522 | if ((start - i->position + 1 + length) < LENGTH (i) | |
1523 | && DEFAULT_INTERVAL_P (i)) | |
1524 | return NULL_INTERVAL; | |
1525 | ||
1526 | new = make_interval (); | |
1527 | new->position = 1; | |
1528 | got = (LENGTH (i) - (start - i->position)); | |
9c79dd1b | 1529 | new->total_length = length; |
a50699fd JA |
1530 | copy_properties (i, new); |
1531 | ||
1532 | t = new; | |
1533 | while (got < length) | |
1534 | { | |
1535 | i = next_interval (i); | |
9c79dd1b | 1536 | t = split_interval_right (t, got + 1); |
a50699fd JA |
1537 | copy_properties (i, t); |
1538 | got += LENGTH (i); | |
1539 | } | |
1540 | ||
1541 | if (got > length) | |
1542 | t->total_length -= (got - length); | |
1543 | ||
1544 | return balance_intervals (new); | |
1545 | } | |
1546 | ||
a50699fd JA |
1547 | /* Give STRING the properties of BUFFER from POSITION to LENGTH. */ |
1548 | ||
d7e3e52b | 1549 | INLINE void |
a50699fd JA |
1550 | copy_intervals_to_string (string, buffer, position, length) |
1551 | Lisp_Object string, buffer; | |
1552 | int position, length; | |
1553 | { | |
1554 | INTERVAL interval_copy = copy_intervals (XBUFFER (buffer)->intervals, | |
1555 | position, length); | |
1556 | if (NULL_INTERVAL_P (interval_copy)) | |
1557 | return; | |
1558 | ||
1559 | interval_copy->parent = (INTERVAL) string; | |
1560 | XSTRING (string)->intervals = interval_copy; | |
1561 | } | |
d2f7a802 JA |
1562 | |
1563 | #endif /* USE_TEXT_PROPERTIES */ |