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ca4c9455 KH |
1 | /* Composite sequence support. |
2 | Copyright (C) 1999 Electrotechnical Laboratory, JAPAN. | |
3 | Licensed to the Free Software Foundation. | |
4 | ||
5 | This file is part of GNU Emacs. | |
6 | ||
7 | GNU Emacs is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 2, or (at your option) | |
10 | any later version. | |
11 | ||
12 | GNU Emacs is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with GNU Emacs; 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. */ | |
21 | ||
22 | #include <config.h> | |
23 | #include "lisp.h" | |
24 | #include "buffer.h" | |
25 | #include "charset.h" | |
26 | #include "intervals.h" | |
27 | ||
28 | /* Emacs uses special text property `composition' to support character | |
29 | composition. A sequence of characters that have the same (i.e. eq) | |
30 | `composition' property value is treated as a single composite | |
31 | sequence (we call it just `composition' here after). Characters in | |
32 | a composition are all composed somehow on the screen. | |
33 | ||
34 | The property value has this form when the composition is made: | |
35 | ((LENGTH . COMPONENTS) . MODIFICATION-FUNC) | |
36 | then turns to this form: | |
37 | (COMPOSITION-ID . (LENGTH COMPONENTS-VEC . MODIFICATION-FUNC)) | |
38 | when the composition is registered in composition_hash_table and | |
39 | composition_table. These rather peculiar structures were designed | |
40 | to make it easy to distinguish them quickly (we can do that by | |
41 | checking only the first element) and to extract LENGTH (from the | |
42 | former form) and COMPOSITION-ID (from the latter form). | |
43 | ||
44 | We register a composition when it is displayed, or when the width | |
45 | is required (for instance, to calculate columns). | |
46 | ||
47 | LENGTH -- Length of the composition. This information is used to | |
48 | check the validity of the composition. | |
49 | ||
50 | COMPONENTS -- Character, string, vector, list, or nil. | |
51 | ||
52 | If it is nil, characters in the text are composed relatively | |
53 | according to their metrics in font glyphs. | |
54 | ||
55 | If it is a character or a string, the character or characters | |
56 | in the string are composed relatively. | |
57 | ||
58 | If it is a vector or list of integers, the element is a | |
59 | character or an encoded composition rule. The characters are | |
60 | composed according to the rules. (2N)th elements are | |
61 | characters to be composed and (2N+1)th elements are | |
62 | composition rules to tell how to compose (2N+2)th element with | |
63 | the previously composed 2N glyphs. | |
64 | ||
65 | COMPONENTS-VEC -- Vector of integers. In relative composition, the | |
66 | elements are characters to be composed. In rule-base | |
67 | composition, the elements are characters or encoded | |
68 | composition rules. | |
69 | ||
70 | MODIFICATION-FUNC -- If non nil, it is a function to call when the | |
71 | composition gets invalid after a modification in a buffer. If | |
72 | it is nil, a function in `composition-function-table' of the | |
73 | first character in the sequence is called. | |
74 | ||
75 | COMPOSITION-ID --Identification number of the composition. It is | |
76 | used as an index to composition_table for the composition. | |
77 | ||
78 | When Emacs has to display a composition or has to know its | |
79 | displaying width, the function get_composition_id is called. It | |
80 | returns COMPOSITION-ID so that the caller can access the | |
81 | information about the composition through composition_table. If a | |
82 | COMPOSITION-ID has not yet been assigned to the composition, | |
83 | get_composition_id checks the validity of `composition' property, | |
84 | and, if valid, assigns a new ID, registers the information in | |
85 | composition_hash_table and composition_table, and changes the form | |
86 | of the property value. If the property is invalid, return -1 | |
87 | without changing the property value. | |
88 | ||
89 | We use two tables to keep information about composition; | |
90 | composition_hash_table and composition_table. | |
91 | ||
92 | The former is a hash table in which keys are COMPONENTS-VECs and | |
93 | values are the corresponding COMPOSITION-IDs. This hash table is | |
94 | weak, but as each key (COMPONENTS-VEC) is also kept as a value of | |
95 | `composition' property, it won't be collected as garbage until all | |
96 | text that have the same COMPONENTS-VEC are deleted. | |
97 | ||
98 | The latter is a table of pointers to `struct composition' indexed | |
99 | by COMPOSITION-ID. This structure keep the other information (see | |
100 | composite.h). | |
101 | ||
102 | In general, a text property holds information about individual | |
103 | characters. But, a `composition' property holds information about | |
104 | a sequence of characters (in this sense, it is like `intangible' | |
105 | property). That means that we should not share the property value | |
106 | in adjacent compositions we can't distinguish them if they have the | |
107 | same property. So, after any changes, we call | |
108 | `update_compositions' and change a property of one of adjacent | |
109 | compositions to a copy of it. This function also runs a proper | |
110 | composition modification function to make a composition that gets | |
111 | invalid by the change valid again. | |
112 | ||
113 | As a value of `composition' property holds information about a | |
114 | specific range of text, the value gets invalid if we change the | |
115 | text in the range. We treat `composition' property always | |
116 | rear-nonsticky (currently by setting default-text-properties to | |
117 | (rear-nonsticky (composition))) and we never make properties of | |
118 | adjacent compositions identical. Thus, any such changes make the | |
119 | range just shorter. So, we can check the validity of `composition' | |
120 | property by comparing LENGTH information with the actual length of | |
121 | the composition. | |
122 | ||
123 | */ | |
124 | ||
125 | ||
126 | Lisp_Object Qcomposition; | |
127 | ||
128 | /* Table of pointers to the structure `composition' indexed by | |
129 | COMPOSITION-ID. This structure is for storing information about | |
130 | each composition except for COMPONENTS-VEC. */ | |
131 | struct composition **composition_table; | |
132 | ||
133 | /* The current size of `composition_table'. */ | |
134 | static int composition_table_size; | |
135 | ||
136 | /* Number of compositions currently made. */ | |
137 | int n_compositions; | |
138 | ||
139 | /* Hash table for compositions. The key is COMPONENTS-VEC of | |
140 | `composition' property. The value is the corresponding | |
141 | COMPOSITION-ID. */ | |
142 | Lisp_Object composition_hash_table; | |
143 | ||
144 | /* Function to call to adjust composition. */ | |
145 | Lisp_Object Vcompose_chars_after_function; | |
146 | ||
147 | /* Temporary variable used in macros COMPOSITION_XXX. */ | |
148 | Lisp_Object composition_temp; | |
149 | \f | |
150 | /* Return how many columns C will occupy on the screen. It always | |
151 | returns 1 for control characters and 8-bit characters because those | |
152 | are just ignored in a composition. */ | |
153 | #define CHAR_WIDTH(c) \ | |
154 | (SINGLE_BYTE_CHAR_P (c) ? 1 : CHARSET_WIDTH (CHAR_CHARSET (c))) | |
155 | ||
156 | /* The following macros for hash table are copied from fns.c. */ | |
ca4c9455 KH |
157 | /* Value is the key part of entry IDX in hash table H. */ |
158 | #define HASH_KEY(H, IDX) AREF ((H)->key_and_value, 2 * (IDX)) | |
159 | /* Value is the value part of entry IDX in hash table H. */ | |
160 | #define HASH_VALUE(H, IDX) AREF ((H)->key_and_value, 2 * (IDX) + 1) | |
161 | ||
162 | /* Return COMPOSITION-ID of a composition at buffer position | |
163 | CHARPOS/BYTEPOS and length NCHARS. The `composition' property of | |
164 | the sequence is PROP. STRING, if non-nil, is a string that | |
165 | contains the composition instead of the current buffer. | |
166 | ||
167 | If the composition is invalid, return -1. */ | |
168 | ||
169 | int | |
170 | get_composition_id (charpos, bytepos, nchars, prop, string) | |
171 | int charpos, bytepos, nchars; | |
172 | Lisp_Object prop, string; | |
173 | { | |
174 | Lisp_Object id, length, components, key, *key_contents; | |
175 | int glyph_len; | |
176 | struct Lisp_Hash_Table *hash_table = XHASH_TABLE (composition_hash_table); | |
177 | int hash_index; | |
178 | unsigned hash_code; | |
179 | struct composition *cmp; | |
180 | int i, ch; | |
181 | ||
182 | /* PROP should be | |
183 | Form-A: ((LENGTH . COMPONENTS) . MODIFICATION-FUNC) | |
184 | or | |
185 | Form-B: (COMPOSITION-ID . (LENGTH COMPONENTS-VEC . MODIFICATION-FUNC)) | |
186 | */ | |
187 | if (nchars == 0 || !CONSP (prop)) | |
188 | goto invalid_composition; | |
189 | ||
190 | id = XCAR (prop); | |
191 | if (INTEGERP (id)) | |
192 | { | |
193 | /* PROP should be Form-B. */ | |
194 | if (XINT (id) < 0 || XINT (id) >= n_compositions) | |
195 | goto invalid_composition; | |
196 | return XINT (id); | |
197 | } | |
198 | ||
199 | /* PROP should be Form-A. | |
200 | Thus, ID should be (LENGTH . COMPONENTS). */ | |
201 | if (!CONSP (id)) | |
202 | goto invalid_composition; | |
203 | length = XCAR (id); | |
204 | if (!INTEGERP (length) || XINT (length) != nchars) | |
205 | goto invalid_composition; | |
206 | ||
207 | components = XCDR (id); | |
208 | ||
209 | /* Check if the same composition has already been registered or not | |
210 | by consulting composition_hash_table. The key for this table is | |
211 | COMPONENTS (converted to a vector COMPONENTS-VEC) or, if it is | |
212 | nil, vector of characters in the composition range. */ | |
213 | if (INTEGERP (components)) | |
214 | key = Fmake_vector (make_number (1), components); | |
215 | else if (STRINGP (components) || CONSP (components)) | |
216 | key = Fvconcat (1, &components); | |
217 | else if (VECTORP (components)) | |
218 | key = components; | |
219 | else if (NILP (components)) | |
220 | { | |
221 | key = Fmake_vector (make_number (nchars), Qnil); | |
222 | if (STRINGP (string)) | |
223 | for (i = 0; i < nchars; i++) | |
224 | { | |
225 | FETCH_STRING_CHAR_ADVANCE (ch, string, charpos, bytepos); | |
226 | XVECTOR (key)->contents[i] = make_number (ch); | |
227 | } | |
228 | else | |
229 | for (i = 0; i < nchars; i++) | |
230 | { | |
231 | FETCH_CHAR_ADVANCE (ch, charpos, bytepos); | |
232 | XVECTOR (key)->contents[i] = make_number (ch); | |
233 | } | |
234 | } | |
235 | else | |
236 | goto invalid_composition; | |
237 | ||
238 | hash_index = hash_lookup (hash_table, key, &hash_code); | |
239 | if (hash_index >= 0) | |
240 | { | |
241 | /* We have already registered the same composition. Change PROP | |
242 | from Form-A above to Form-B while replacing COMPONENTS with | |
243 | COMPONENTS-VEC stored in the hash table. We can directly | |
244 | modify the cons cell of PROP because it is not shared. */ | |
245 | key = HASH_KEY (hash_table, hash_index); | |
246 | id = HASH_VALUE (hash_table, hash_index); | |
247 | XCAR (prop) = id; | |
248 | XCDR (prop) = Fcons (make_number (nchars), Fcons (key, XCDR (prop))); | |
249 | return XINT (id); | |
250 | } | |
251 | ||
252 | /* This composition is a new one. We must register it. */ | |
253 | ||
254 | /* Check if we have sufficient memory to store this information. */ | |
255 | if (composition_table_size == 0) | |
256 | { | |
257 | composition_table_size = 256; | |
258 | composition_table | |
259 | = (struct composition **) xmalloc (sizeof (composition_table[0]) | |
260 | * composition_table_size); | |
261 | } | |
262 | else if (composition_table_size <= n_compositions) | |
263 | { | |
264 | composition_table_size += 256; | |
265 | composition_table | |
266 | = (struct composition **) xrealloc (composition_table, | |
267 | sizeof (composition_table[0]) | |
268 | * composition_table_size); | |
269 | } | |
270 | ||
271 | key_contents = XVECTOR (key)->contents; | |
272 | ||
273 | /* Check if the contents of COMPONENTS are valid if COMPONENTS is a | |
274 | vector or a list. It should be a sequence of: | |
275 | char1 rule1 char2 rule2 char3 ... ruleN charN+1 */ | |
276 | if (VECTORP (components) || CONSP (components)) | |
277 | { | |
278 | int len = XVECTOR (key)->size; | |
279 | ||
280 | /* The number of elements should be odd. */ | |
281 | if ((len % 2) == 0) | |
282 | goto invalid_composition; | |
283 | /* All elements should be integers (character or encoded | |
284 | composition rule). */ | |
285 | for (i = 0; i < len; i++) | |
286 | { | |
287 | if (!INTEGERP (key_contents[i])) | |
288 | goto invalid_composition; | |
289 | } | |
290 | } | |
291 | ||
292 | /* Change PROP from Form-A above to Form-B. We can directly modify | |
293 | the cons cell of PROP because it is not shared. */ | |
294 | XSETFASTINT (id, n_compositions); | |
295 | XCAR (prop) = id; | |
296 | XCDR (prop) = Fcons (make_number (nchars), Fcons (key, XCDR (prop))); | |
297 | ||
298 | /* Register the composition in composition_hash_table. */ | |
299 | hash_index = hash_put (hash_table, key, id, hash_code); | |
300 | ||
301 | /* Register the composition in composition_table. */ | |
302 | cmp = (struct composition *) xmalloc (sizeof (struct composition)); | |
303 | ||
304 | cmp->method = (NILP (components) | |
305 | ? COMPOSITION_RELATIVE | |
306 | : ((INTEGERP (components) || STRINGP (components)) | |
307 | ? COMPOSITION_WITH_ALTCHARS | |
308 | : COMPOSITION_WITH_RULE_ALTCHARS)); | |
309 | cmp->hash_index = hash_index; | |
310 | glyph_len = (cmp->method == COMPOSITION_WITH_RULE_ALTCHARS | |
311 | ? (XVECTOR (key)->size + 1) / 2 | |
312 | : XVECTOR (key)->size); | |
313 | cmp->glyph_len = glyph_len; | |
314 | cmp->offsets = (short *) xmalloc (sizeof (short) * glyph_len * 2); | |
315 | cmp->font = NULL; | |
316 | ||
317 | /* Calculate the width of overall glyphs of the composition. */ | |
318 | if (cmp->method != COMPOSITION_WITH_RULE_ALTCHARS) | |
319 | { | |
320 | /* Relative composition. */ | |
321 | cmp->width = 0; | |
322 | for (i = 0; i < glyph_len; i++) | |
323 | { | |
324 | int this_width; | |
325 | ch = XINT (key_contents[i]); | |
326 | this_width = CHAR_WIDTH (ch); | |
327 | if (cmp->width < this_width) | |
328 | cmp->width = this_width; | |
329 | } | |
330 | } | |
331 | else | |
332 | { | |
333 | /* Rule-base composition. */ | |
334 | float leftmost = 0.0, rightmost; | |
335 | ||
336 | ch = XINT (key_contents[0]); | |
337 | rightmost = CHAR_WIDTH (ch); | |
338 | ||
339 | for (i = 1; i < glyph_len; i += 2) | |
340 | { | |
341 | int rule, gref, nref; | |
342 | int this_width; | |
343 | float this_left; | |
344 | ||
345 | rule = XINT (key_contents[i]); | |
346 | ch = XINT (key_contents[i + 1]); | |
347 | this_width = CHAR_WIDTH (ch); | |
348 | ||
349 | /* A composition rule is specified by an integer value | |
350 | that encodes global and new reference points (GREF and | |
351 | NREF). GREF and NREF are specified by numbers as | |
352 | below: | |
353 | 0---1---2 -- ascent | |
354 | | | | |
355 | | | | |
356 | | | | |
357 | 9--10--11 -- center | |
358 | | | | |
359 | ---3---4---5--- baseline | |
360 | | | | |
361 | 6---7---8 -- descent | |
362 | */ | |
363 | COMPOSITION_DECODE_RULE (rule, gref, nref); | |
364 | this_left = (leftmost | |
365 | + (gref % 3) * (rightmost - leftmost) / 2.0 | |
366 | - (nref % 3) * this_width / 2.0); | |
367 | ||
368 | if (this_left < leftmost) | |
369 | leftmost = this_left; | |
370 | if (this_left + this_width > rightmost) | |
371 | rightmost = this_left + this_width; | |
372 | } | |
373 | ||
374 | cmp->width = rightmost - leftmost; | |
375 | if (cmp->width < (rightmost - leftmost)) | |
376 | /* To get a ceiling integer value. */ | |
377 | cmp->width++; | |
378 | } | |
379 | ||
380 | composition_table[n_compositions] = cmp; | |
381 | ||
382 | return n_compositions++; | |
383 | ||
384 | invalid_composition: | |
385 | /* Would it be better to remove this `composition' property? */ | |
386 | return -1; | |
387 | } | |
388 | ||
389 | \f | |
390 | /* Find a composition at or nearest to position POS of OBJECT (buffer | |
391 | or string). | |
392 | ||
393 | OBJECT defaults to the current buffer. If there's a composition at | |
394 | POS, set *START and *END to the start and end of the sequence, | |
395 | *PROP to the `composition' property, and return 1. | |
396 | ||
397 | If there's no composition at POS and LIMIT is negative, return 0. | |
398 | ||
399 | Otherwise, search for a composition forward (LIMIT > POS) or | |
400 | backward (LIMIT < POS). In this case, LIMIT bounds the search. | |
401 | ||
402 | If a composition is found, set *START, *END, and *PROP as above, | |
403 | and return 1, else return 0. | |
404 | ||
405 | This doesn't check the validity of composition. */ | |
406 | ||
407 | int | |
408 | find_composition (pos, limit, start, end, prop, object) | |
409 | int pos, limit, *start, *end; | |
410 | Lisp_Object *prop, object; | |
411 | { | |
412 | Lisp_Object val; | |
413 | ||
414 | if (get_property_and_range (pos, Qcomposition, prop, start, end, object)) | |
415 | return 1; | |
416 | ||
417 | if (limit < 0 || limit == pos) | |
418 | return 0; | |
419 | ||
420 | if (limit > pos) /* search forward */ | |
421 | val = Fnext_single_property_change (make_number (pos), Qcomposition, | |
422 | object, make_number (limit)); | |
423 | else /* search backward */ | |
424 | val = Fprevious_single_property_change (make_number (pos), Qcomposition, | |
425 | object, make_number (limit)); | |
426 | pos = XINT (val); | |
427 | if (pos == limit) | |
428 | return 0; | |
429 | get_property_and_range (pos, Qcomposition, prop, start, end, object); | |
430 | return 1; | |
431 | } | |
432 | ||
433 | /* Run a proper function to adjust the composition sitting between | |
434 | FROM and TO with property PROP. */ | |
435 | ||
436 | static void | |
437 | run_composition_function (from, to, prop) | |
438 | int from, to; | |
439 | Lisp_Object prop; | |
440 | { | |
441 | Lisp_Object func, val; | |
442 | int start, end; | |
443 | ||
444 | func = COMPOSITION_MODIFICATION_FUNC (prop); | |
445 | /* If an invalid composition precedes or follows, try to make them | |
446 | valid too. */ | |
447 | if (from > BEGV | |
448 | && find_composition (from - 1, -1, &start, &end, &prop, Qnil) | |
449 | && !COMPOSITION_VALID_P (start, end, prop)) | |
450 | from = start; | |
451 | if (to < ZV | |
452 | && find_composition (to, -1, &start, &end, &prop, Qnil) | |
453 | && !COMPOSITION_VALID_P (start, end, prop)) | |
454 | to = end; | |
455 | if (!NILP (func)) | |
456 | call2 (func, make_number (from), make_number (to)); | |
09654086 | 457 | else if (!NILP (Ffboundp (Vcompose_chars_after_function))) |
ca4c9455 KH |
458 | call2 (Vcompose_chars_after_function, |
459 | make_number (from), make_number (to)); | |
460 | } | |
461 | ||
462 | /* Make invalid compositions adjacent to or inside FROM and TO valid. | |
463 | CHECK_MASK is bitwise `or' of mask bits defined by macros | |
464 | CHECK_XXX (see the comment in composite.h). | |
465 | ||
466 | This function is called when a buffer text is changed. If the | |
467 | change is deletion, FROM == TO. Otherwise, FROM < TO. */ | |
468 | ||
469 | void | |
470 | update_compositions (from, to, check_mask) | |
471 | int from, to; | |
472 | { | |
473 | Lisp_Object prop, hook; | |
474 | int start, end; | |
475 | ||
d3f40cbd KH |
476 | /* If FROM and TO are not in a valid range, do nothing. */ |
477 | if (! (BEGV <= from && from <= to && to <= ZV)) | |
478 | return; | |
479 | ||
ca4c9455 KH |
480 | if (check_mask & CHECK_HEAD) |
481 | { | |
482 | /* FROM should be at composition boundary. But, insertion or | |
483 | deletion will make two compositions adjacent and | |
484 | indistinguishable when they have same (eq) property. To | |
485 | avoid it, in such a case, we change the property of the | |
486 | latter to the copy of it. */ | |
487 | if (from > BEGV | |
488 | && find_composition (from - 1, -1, &start, &end, &prop, Qnil)) | |
489 | { | |
490 | if (from < end) | |
491 | Fput_text_property (make_number (from), make_number (end), | |
492 | Qcomposition, | |
493 | Fcons (XCAR (prop), XCDR (prop)), Qnil); | |
494 | run_composition_function (start, end, prop); | |
495 | from = end; | |
496 | } | |
497 | else if (from < end | |
498 | && find_composition (from, -1, &start, &from, &prop, Qnil)) | |
499 | run_composition_function (start, from, prop); | |
500 | } | |
501 | ||
502 | if (check_mask & CHECK_INSIDE) | |
503 | { | |
504 | /* In this case, we are sure that (check & CHECK_TAIL) is also | |
505 | nonzero. Thus, here we should check only compositions before | |
506 | (to - 1). */ | |
507 | while (from < to - 1 | |
508 | && find_composition (from, to, &start, &from, &prop, Qnil) | |
509 | && from < to - 1) | |
510 | run_composition_function (start, from, prop); | |
511 | } | |
512 | ||
513 | if (check_mask & CHECK_TAIL) | |
514 | { | |
515 | if (from < to | |
516 | && find_composition (to - 1, -1, &start, &end, &prop, Qnil)) | |
517 | { | |
518 | /* TO should be also at composition boundary. But, | |
519 | insertion or deletion will make two compositions adjacent | |
520 | and indistinguishable when they have same (eq) property. | |
521 | To avoid it, in such a case, we change the property of | |
522 | the former to the copy of it. */ | |
523 | if (to < end) | |
524 | Fput_text_property (make_number (start), make_number (to), | |
525 | Qcomposition, | |
526 | Fcons (XCAR (prop), XCDR (prop)), Qnil); | |
527 | run_composition_function (start, end, prop); | |
528 | } | |
529 | else if (to < ZV | |
530 | && find_composition (to, -1, &start, &end, &prop, Qnil)) | |
531 | run_composition_function (start, end, prop); | |
532 | } | |
533 | } | |
534 | ||
c1361885 KH |
535 | |
536 | /* Modify composition property values in LIST destructively. LIST is | |
537 | a list as returned from text_property_list. Change values to the | |
538 | top-level copies of them so that none of them are `eq'. */ | |
539 | ||
540 | void | |
541 | make_composition_value_copy (list) | |
542 | Lisp_Object list; | |
543 | { | |
544 | Lisp_Object plist, val; | |
545 | ||
546 | for (; CONSP (list); list = XCDR (list)) | |
547 | { | |
548 | plist = XCAR (XCDR (XCDR (XCAR (list)))); | |
549 | while (CONSP (plist) && CONSP (XCDR (plist))) | |
550 | { | |
551 | if (EQ (XCAR (plist), Qcomposition) | |
552 | && (val = XCAR (XCDR (plist)), CONSP (val))) | |
553 | XCAR (XCDR (plist)) = Fcons (XCAR (val), XCDR (val)); | |
554 | plist = XCDR (XCDR (plist)); | |
555 | } | |
556 | } | |
557 | } | |
558 | ||
559 | ||
ca4c9455 KH |
560 | /* Make text in the region between START and END a composition that |
561 | has COMPONENTS and MODIFICATION-FUNC. | |
562 | ||
563 | If STRING is non-nil, then operate on characters contained between | |
564 | indices START and END in STRING. */ | |
565 | ||
566 | void | |
567 | compose_text (start, end, components, modification_func, string) | |
568 | int start, end; | |
569 | Lisp_Object components, modification_func, string; | |
570 | { | |
571 | Lisp_Object prop; | |
572 | ||
573 | prop = Fcons (Fcons (make_number (end - start), components), | |
574 | modification_func); | |
575 | Fput_text_property (make_number (start), make_number (end), | |
576 | Qcomposition, prop, string); | |
577 | } | |
578 | ||
579 | \f | |
580 | /* Emacs Lisp APIs. */ | |
581 | ||
582 | DEFUN ("compose-region-internal", Fcompose_region_internal, | |
583 | Scompose_region_internal, 2, 4, 0, | |
584 | "Internal use only.\n\ | |
585 | \n\ | |
586 | Compose text in the region between START and END.\n\ | |
587 | Optional 3rd and 4th arguments are COMPONENTS and MODIFICATION-FUNC\n\ | |
588 | for the composition. See `compose-region' for more detial.") | |
589 | (start, end, components, mod_func) | |
590 | Lisp_Object start, end, components, mod_func; | |
591 | { | |
592 | validate_region (&start, &end); | |
593 | if (!NILP (components) | |
594 | && !INTEGERP (components) | |
595 | && !CONSP (components) | |
596 | && !STRINGP (components)) | |
597 | CHECK_VECTOR (components, 2); | |
598 | ||
599 | compose_text (XINT (start), XINT (end), components, mod_func, Qnil); | |
600 | return Qnil; | |
601 | } | |
602 | ||
603 | DEFUN ("compose-string-internal", Fcompose_string_internal, | |
604 | Scompose_string_internal, 3, 5, 0, | |
605 | "Internal use only.\n\ | |
606 | \n\ | |
607 | Compose text between indices START and END of STRING.\n\ | |
608 | Optional 4th and 5th arguments are COMPONENTS and MODIFICATION-FUNC\n\ | |
609 | for the composition. See `compose-string' for more detial.") | |
610 | (string, start, end, components, mod_func) | |
611 | Lisp_Object string, start, end, components, mod_func; | |
612 | { | |
613 | CHECK_STRING (string, 0); | |
614 | CHECK_NUMBER (start, 1); | |
615 | CHECK_NUMBER (end, 2); | |
616 | ||
617 | if (XINT (start) < 0 || | |
618 | XINT (start) > XINT (end) | |
619 | || XINT (end) > XSTRING (string)->size) | |
620 | args_out_of_range (start, end); | |
621 | ||
622 | compose_text (XINT (start), XINT (end), components, mod_func, string); | |
623 | return string; | |
624 | } | |
625 | ||
626 | DEFUN ("find-composition-internal", Ffind_composition_internal, | |
627 | Sfind_composition_internal, 4, 4, 0, | |
628 | "Internal use only.\n\ | |
629 | \n\ | |
630 | Return information about composition at or nearest to position POS.\n\ | |
631 | See `find-composition' for more detail.") | |
632 | (pos, limit, string, detail_p) | |
633 | Lisp_Object pos, limit, string, detail_p; | |
634 | { | |
635 | Lisp_Object prop, tail; | |
636 | int start, end; | |
637 | int id; | |
638 | ||
639 | CHECK_NUMBER_COERCE_MARKER (pos, 0); | |
640 | start = XINT (pos); | |
641 | if (!NILP (limit)) | |
642 | { | |
643 | CHECK_NUMBER_COERCE_MARKER (limit, 1); | |
644 | end = XINT (limit); | |
645 | } | |
646 | else | |
647 | end = -1; | |
648 | if (!NILP (string)) | |
649 | CHECK_STRING (string, 2); | |
650 | ||
651 | if (!find_composition (start, end, &start, &end, &prop, string)) | |
652 | return Qnil; | |
653 | if (!COMPOSITION_VALID_P (start, end, prop)) | |
654 | return Fcons (make_number (start), Fcons (make_number (end), | |
655 | Fcons (Qnil, Qnil))); | |
656 | if (NILP (detail_p)) | |
657 | return Fcons (make_number (start), Fcons (make_number (end), | |
658 | Fcons (Qt, Qnil))); | |
659 | ||
660 | if (COMPOSITION_REGISTERD_P (prop)) | |
661 | id = COMPOSITION_ID (prop); | |
662 | else | |
663 | { | |
664 | int start_byte = (NILP (string) | |
665 | ? CHAR_TO_BYTE (start) | |
666 | : string_char_to_byte (string, start)); | |
667 | id = get_composition_id (start, start_byte, end - start, prop, string); | |
668 | } | |
669 | ||
670 | if (id >= 0) | |
671 | { | |
672 | Lisp_Object components, relative_p, mod_func; | |
673 | enum composition_method method = COMPOSITION_METHOD (prop); | |
674 | int width = composition_table[id]->width; | |
675 | ||
676 | components = Fcopy_sequence (COMPOSITION_COMPONENTS (prop)); | |
677 | relative_p = (method == COMPOSITION_WITH_RULE_ALTCHARS | |
678 | ? Qnil : Qt); | |
679 | mod_func = COMPOSITION_MODIFICATION_FUNC (prop); | |
680 | tail = Fcons (components, | |
681 | Fcons (relative_p, | |
682 | Fcons (mod_func, | |
683 | Fcons (make_number (width), Qnil)))); | |
684 | } | |
685 | else | |
686 | tail = Qnil; | |
687 | ||
688 | return Fcons (make_number (start), Fcons (make_number (end), tail)); | |
689 | } | |
690 | ||
691 | \f | |
692 | void | |
693 | syms_of_composite () | |
694 | { | |
695 | Qcomposition = intern ("composition"); | |
696 | staticpro (&Qcomposition); | |
697 | ||
698 | /* Make a hash table for composition. */ | |
699 | { | |
09654086 | 700 | Lisp_Object args[6]; |
ca4c9455 KH |
701 | extern Lisp_Object QCsize; |
702 | ||
703 | args[0] = QCtest; | |
704 | args[1] = Qequal; | |
705 | args[2] = QCweakness; | |
706 | args[3] = Qnil; | |
707 | args[4] = QCsize; | |
708 | args[5] = make_number (311); | |
09654086 | 709 | composition_hash_table = Fmake_hash_table (6, args); |
ca4c9455 KH |
710 | staticpro (&composition_hash_table); |
711 | } | |
712 | ||
713 | /* Text property `composition' should be nonsticky by default. */ | |
714 | Vtext_property_default_nonsticky | |
715 | = Fcons (Fcons (Qcomposition, Qt), Vtext_property_default_nonsticky); | |
716 | ||
717 | DEFVAR_LISP ("compose-chars-after-function", &Vcompose_chars_after_function, | |
718 | "Function to adjust composition of buffer text.\n\ | |
719 | \n\ | |
720 | This function is called after a text with `composition' property is\n\ | |
721 | inserted or deleted to keep `composition' property of buffer text\n\ | |
722 | valid.\n\ | |
723 | \n\ | |
724 | The function is called with two arguments FROM and TO. They specify\n\ | |
725 | the range of text of which composition should be adjusted.\n\ | |
726 | \n\ | |
727 | The default value is the function `compose-chars-after'."); | |
728 | Vcompose_chars_after_function = intern ("compose-chars-after"); | |
729 | ||
730 | defsubr (&Scompose_region_internal); | |
731 | defsubr (&Scompose_string_internal); | |
732 | defsubr (&Sfind_composition_internal); | |
733 | } |