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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 | ||
40add26d KH |
147 | /* Char-table of patterns and functions to make a composition. */ |
148 | Lisp_Object Vcomposition_function_table; | |
149 | Lisp_Object Qcomposition_function_table; | |
150 | ||
ca4c9455 KH |
151 | /* Temporary variable used in macros COMPOSITION_XXX. */ |
152 | Lisp_Object composition_temp; | |
153 | \f | |
154 | /* Return how many columns C will occupy on the screen. It always | |
155 | returns 1 for control characters and 8-bit characters because those | |
156 | are just ignored in a composition. */ | |
157 | #define CHAR_WIDTH(c) \ | |
158 | (SINGLE_BYTE_CHAR_P (c) ? 1 : CHARSET_WIDTH (CHAR_CHARSET (c))) | |
159 | ||
160 | /* The following macros for hash table are copied from fns.c. */ | |
ca4c9455 KH |
161 | /* Value is the key part of entry IDX in hash table H. */ |
162 | #define HASH_KEY(H, IDX) AREF ((H)->key_and_value, 2 * (IDX)) | |
163 | /* Value is the value part of entry IDX in hash table H. */ | |
164 | #define HASH_VALUE(H, IDX) AREF ((H)->key_and_value, 2 * (IDX) + 1) | |
165 | ||
166 | /* Return COMPOSITION-ID of a composition at buffer position | |
167 | CHARPOS/BYTEPOS and length NCHARS. The `composition' property of | |
168 | the sequence is PROP. STRING, if non-nil, is a string that | |
169 | contains the composition instead of the current buffer. | |
170 | ||
171 | If the composition is invalid, return -1. */ | |
172 | ||
173 | int | |
174 | get_composition_id (charpos, bytepos, nchars, prop, string) | |
175 | int charpos, bytepos, nchars; | |
176 | Lisp_Object prop, string; | |
177 | { | |
178 | Lisp_Object id, length, components, key, *key_contents; | |
179 | int glyph_len; | |
180 | struct Lisp_Hash_Table *hash_table = XHASH_TABLE (composition_hash_table); | |
181 | int hash_index; | |
182 | unsigned hash_code; | |
183 | struct composition *cmp; | |
184 | int i, ch; | |
185 | ||
186 | /* PROP should be | |
187 | Form-A: ((LENGTH . COMPONENTS) . MODIFICATION-FUNC) | |
188 | or | |
189 | Form-B: (COMPOSITION-ID . (LENGTH COMPONENTS-VEC . MODIFICATION-FUNC)) | |
190 | */ | |
191 | if (nchars == 0 || !CONSP (prop)) | |
192 | goto invalid_composition; | |
193 | ||
194 | id = XCAR (prop); | |
195 | if (INTEGERP (id)) | |
196 | { | |
197 | /* PROP should be Form-B. */ | |
198 | if (XINT (id) < 0 || XINT (id) >= n_compositions) | |
199 | goto invalid_composition; | |
200 | return XINT (id); | |
201 | } | |
202 | ||
203 | /* PROP should be Form-A. | |
204 | Thus, ID should be (LENGTH . COMPONENTS). */ | |
205 | if (!CONSP (id)) | |
206 | goto invalid_composition; | |
207 | length = XCAR (id); | |
208 | if (!INTEGERP (length) || XINT (length) != nchars) | |
209 | goto invalid_composition; | |
210 | ||
211 | components = XCDR (id); | |
212 | ||
213 | /* Check if the same composition has already been registered or not | |
214 | by consulting composition_hash_table. The key for this table is | |
215 | COMPONENTS (converted to a vector COMPONENTS-VEC) or, if it is | |
216 | nil, vector of characters in the composition range. */ | |
217 | if (INTEGERP (components)) | |
218 | key = Fmake_vector (make_number (1), components); | |
219 | else if (STRINGP (components) || CONSP (components)) | |
220 | key = Fvconcat (1, &components); | |
221 | else if (VECTORP (components)) | |
222 | key = components; | |
223 | else if (NILP (components)) | |
224 | { | |
225 | key = Fmake_vector (make_number (nchars), Qnil); | |
226 | if (STRINGP (string)) | |
227 | for (i = 0; i < nchars; i++) | |
228 | { | |
229 | FETCH_STRING_CHAR_ADVANCE (ch, string, charpos, bytepos); | |
230 | XVECTOR (key)->contents[i] = make_number (ch); | |
231 | } | |
232 | else | |
233 | for (i = 0; i < nchars; i++) | |
234 | { | |
235 | FETCH_CHAR_ADVANCE (ch, charpos, bytepos); | |
236 | XVECTOR (key)->contents[i] = make_number (ch); | |
237 | } | |
238 | } | |
239 | else | |
240 | goto invalid_composition; | |
241 | ||
242 | hash_index = hash_lookup (hash_table, key, &hash_code); | |
243 | if (hash_index >= 0) | |
244 | { | |
245 | /* We have already registered the same composition. Change PROP | |
246 | from Form-A above to Form-B while replacing COMPONENTS with | |
247 | COMPONENTS-VEC stored in the hash table. We can directly | |
248 | modify the cons cell of PROP because it is not shared. */ | |
249 | key = HASH_KEY (hash_table, hash_index); | |
250 | id = HASH_VALUE (hash_table, hash_index); | |
251 | XCAR (prop) = id; | |
252 | XCDR (prop) = Fcons (make_number (nchars), Fcons (key, XCDR (prop))); | |
253 | return XINT (id); | |
254 | } | |
255 | ||
256 | /* This composition is a new one. We must register it. */ | |
257 | ||
258 | /* Check if we have sufficient memory to store this information. */ | |
259 | if (composition_table_size == 0) | |
260 | { | |
261 | composition_table_size = 256; | |
262 | composition_table | |
263 | = (struct composition **) xmalloc (sizeof (composition_table[0]) | |
264 | * composition_table_size); | |
265 | } | |
266 | else if (composition_table_size <= n_compositions) | |
267 | { | |
268 | composition_table_size += 256; | |
269 | composition_table | |
270 | = (struct composition **) xrealloc (composition_table, | |
271 | sizeof (composition_table[0]) | |
272 | * composition_table_size); | |
273 | } | |
274 | ||
275 | key_contents = XVECTOR (key)->contents; | |
276 | ||
277 | /* Check if the contents of COMPONENTS are valid if COMPONENTS is a | |
278 | vector or a list. It should be a sequence of: | |
279 | char1 rule1 char2 rule2 char3 ... ruleN charN+1 */ | |
280 | if (VECTORP (components) || CONSP (components)) | |
281 | { | |
282 | int len = XVECTOR (key)->size; | |
283 | ||
284 | /* The number of elements should be odd. */ | |
285 | if ((len % 2) == 0) | |
286 | goto invalid_composition; | |
287 | /* All elements should be integers (character or encoded | |
288 | composition rule). */ | |
289 | for (i = 0; i < len; i++) | |
290 | { | |
291 | if (!INTEGERP (key_contents[i])) | |
292 | goto invalid_composition; | |
293 | } | |
294 | } | |
295 | ||
296 | /* Change PROP from Form-A above to Form-B. We can directly modify | |
297 | the cons cell of PROP because it is not shared. */ | |
298 | XSETFASTINT (id, n_compositions); | |
299 | XCAR (prop) = id; | |
300 | XCDR (prop) = Fcons (make_number (nchars), Fcons (key, XCDR (prop))); | |
301 | ||
302 | /* Register the composition in composition_hash_table. */ | |
303 | hash_index = hash_put (hash_table, key, id, hash_code); | |
304 | ||
305 | /* Register the composition in composition_table. */ | |
306 | cmp = (struct composition *) xmalloc (sizeof (struct composition)); | |
307 | ||
308 | cmp->method = (NILP (components) | |
309 | ? COMPOSITION_RELATIVE | |
310 | : ((INTEGERP (components) || STRINGP (components)) | |
311 | ? COMPOSITION_WITH_ALTCHARS | |
312 | : COMPOSITION_WITH_RULE_ALTCHARS)); | |
313 | cmp->hash_index = hash_index; | |
314 | glyph_len = (cmp->method == COMPOSITION_WITH_RULE_ALTCHARS | |
315 | ? (XVECTOR (key)->size + 1) / 2 | |
316 | : XVECTOR (key)->size); | |
317 | cmp->glyph_len = glyph_len; | |
318 | cmp->offsets = (short *) xmalloc (sizeof (short) * glyph_len * 2); | |
319 | cmp->font = NULL; | |
320 | ||
321 | /* Calculate the width of overall glyphs of the composition. */ | |
322 | if (cmp->method != COMPOSITION_WITH_RULE_ALTCHARS) | |
323 | { | |
324 | /* Relative composition. */ | |
325 | cmp->width = 0; | |
326 | for (i = 0; i < glyph_len; i++) | |
327 | { | |
328 | int this_width; | |
329 | ch = XINT (key_contents[i]); | |
330 | this_width = CHAR_WIDTH (ch); | |
331 | if (cmp->width < this_width) | |
332 | cmp->width = this_width; | |
333 | } | |
334 | } | |
335 | else | |
336 | { | |
337 | /* Rule-base composition. */ | |
338 | float leftmost = 0.0, rightmost; | |
339 | ||
340 | ch = XINT (key_contents[0]); | |
341 | rightmost = CHAR_WIDTH (ch); | |
342 | ||
343 | for (i = 1; i < glyph_len; i += 2) | |
344 | { | |
345 | int rule, gref, nref; | |
346 | int this_width; | |
347 | float this_left; | |
348 | ||
349 | rule = XINT (key_contents[i]); | |
350 | ch = XINT (key_contents[i + 1]); | |
351 | this_width = CHAR_WIDTH (ch); | |
352 | ||
353 | /* A composition rule is specified by an integer value | |
354 | that encodes global and new reference points (GREF and | |
355 | NREF). GREF and NREF are specified by numbers as | |
356 | below: | |
357 | 0---1---2 -- ascent | |
358 | | | | |
359 | | | | |
360 | | | | |
361 | 9--10--11 -- center | |
362 | | | | |
363 | ---3---4---5--- baseline | |
364 | | | | |
365 | 6---7---8 -- descent | |
366 | */ | |
367 | COMPOSITION_DECODE_RULE (rule, gref, nref); | |
368 | this_left = (leftmost | |
369 | + (gref % 3) * (rightmost - leftmost) / 2.0 | |
370 | - (nref % 3) * this_width / 2.0); | |
371 | ||
372 | if (this_left < leftmost) | |
373 | leftmost = this_left; | |
374 | if (this_left + this_width > rightmost) | |
375 | rightmost = this_left + this_width; | |
376 | } | |
377 | ||
378 | cmp->width = rightmost - leftmost; | |
379 | if (cmp->width < (rightmost - leftmost)) | |
380 | /* To get a ceiling integer value. */ | |
381 | cmp->width++; | |
382 | } | |
383 | ||
384 | composition_table[n_compositions] = cmp; | |
385 | ||
386 | return n_compositions++; | |
387 | ||
388 | invalid_composition: | |
389 | /* Would it be better to remove this `composition' property? */ | |
390 | return -1; | |
391 | } | |
392 | ||
393 | \f | |
394 | /* Find a composition at or nearest to position POS of OBJECT (buffer | |
395 | or string). | |
396 | ||
397 | OBJECT defaults to the current buffer. If there's a composition at | |
398 | POS, set *START and *END to the start and end of the sequence, | |
399 | *PROP to the `composition' property, and return 1. | |
400 | ||
401 | If there's no composition at POS and LIMIT is negative, return 0. | |
402 | ||
403 | Otherwise, search for a composition forward (LIMIT > POS) or | |
404 | backward (LIMIT < POS). In this case, LIMIT bounds the search. | |
405 | ||
406 | If a composition is found, set *START, *END, and *PROP as above, | |
407 | and return 1, else return 0. | |
408 | ||
409 | This doesn't check the validity of composition. */ | |
410 | ||
411 | int | |
412 | find_composition (pos, limit, start, end, prop, object) | |
413 | int pos, limit, *start, *end; | |
414 | Lisp_Object *prop, object; | |
415 | { | |
416 | Lisp_Object val; | |
417 | ||
418 | if (get_property_and_range (pos, Qcomposition, prop, start, end, object)) | |
419 | return 1; | |
420 | ||
421 | if (limit < 0 || limit == pos) | |
422 | return 0; | |
423 | ||
424 | if (limit > pos) /* search forward */ | |
425 | val = Fnext_single_property_change (make_number (pos), Qcomposition, | |
426 | object, make_number (limit)); | |
427 | else /* search backward */ | |
428 | val = Fprevious_single_property_change (make_number (pos), Qcomposition, | |
429 | object, make_number (limit)); | |
430 | pos = XINT (val); | |
431 | if (pos == limit) | |
432 | return 0; | |
433 | get_property_and_range (pos, Qcomposition, prop, start, end, object); | |
434 | return 1; | |
435 | } | |
436 | ||
437 | /* Run a proper function to adjust the composition sitting between | |
438 | FROM and TO with property PROP. */ | |
439 | ||
440 | static void | |
441 | run_composition_function (from, to, prop) | |
442 | int from, to; | |
443 | Lisp_Object prop; | |
444 | { | |
445 | Lisp_Object func, val; | |
446 | int start, end; | |
447 | ||
448 | func = COMPOSITION_MODIFICATION_FUNC (prop); | |
449 | /* If an invalid composition precedes or follows, try to make them | |
450 | valid too. */ | |
451 | if (from > BEGV | |
452 | && find_composition (from - 1, -1, &start, &end, &prop, Qnil) | |
453 | && !COMPOSITION_VALID_P (start, end, prop)) | |
454 | from = start; | |
455 | if (to < ZV | |
456 | && find_composition (to, -1, &start, &end, &prop, Qnil) | |
457 | && !COMPOSITION_VALID_P (start, end, prop)) | |
458 | to = end; | |
459 | if (!NILP (func)) | |
460 | call2 (func, make_number (from), make_number (to)); | |
09654086 | 461 | else if (!NILP (Ffboundp (Vcompose_chars_after_function))) |
40add26d KH |
462 | call3 (Vcompose_chars_after_function, |
463 | make_number (from), make_number (to), Qnil); | |
ca4c9455 KH |
464 | } |
465 | ||
466 | /* Make invalid compositions adjacent to or inside FROM and TO valid. | |
467 | CHECK_MASK is bitwise `or' of mask bits defined by macros | |
468 | CHECK_XXX (see the comment in composite.h). | |
469 | ||
470 | This function is called when a buffer text is changed. If the | |
471 | change is deletion, FROM == TO. Otherwise, FROM < TO. */ | |
472 | ||
473 | void | |
474 | update_compositions (from, to, check_mask) | |
475 | int from, to; | |
476 | { | |
477 | Lisp_Object prop, hook; | |
478 | int start, end; | |
479 | ||
d3f40cbd KH |
480 | /* If FROM and TO are not in a valid range, do nothing. */ |
481 | if (! (BEGV <= from && from <= to && to <= ZV)) | |
482 | return; | |
483 | ||
ca4c9455 KH |
484 | if (check_mask & CHECK_HEAD) |
485 | { | |
486 | /* FROM should be at composition boundary. But, insertion or | |
487 | deletion will make two compositions adjacent and | |
488 | indistinguishable when they have same (eq) property. To | |
489 | avoid it, in such a case, we change the property of the | |
490 | latter to the copy of it. */ | |
491 | if (from > BEGV | |
492 | && find_composition (from - 1, -1, &start, &end, &prop, Qnil)) | |
493 | { | |
494 | if (from < end) | |
495 | Fput_text_property (make_number (from), make_number (end), | |
496 | Qcomposition, | |
497 | Fcons (XCAR (prop), XCDR (prop)), Qnil); | |
498 | run_composition_function (start, end, prop); | |
499 | from = end; | |
500 | } | |
501 | else if (from < end | |
502 | && find_composition (from, -1, &start, &from, &prop, Qnil)) | |
503 | run_composition_function (start, from, prop); | |
504 | } | |
505 | ||
506 | if (check_mask & CHECK_INSIDE) | |
507 | { | |
508 | /* In this case, we are sure that (check & CHECK_TAIL) is also | |
509 | nonzero. Thus, here we should check only compositions before | |
510 | (to - 1). */ | |
511 | while (from < to - 1 | |
512 | && find_composition (from, to, &start, &from, &prop, Qnil) | |
513 | && from < to - 1) | |
514 | run_composition_function (start, from, prop); | |
515 | } | |
516 | ||
517 | if (check_mask & CHECK_TAIL) | |
518 | { | |
519 | if (from < to | |
520 | && find_composition (to - 1, -1, &start, &end, &prop, Qnil)) | |
521 | { | |
522 | /* TO should be also at composition boundary. But, | |
523 | insertion or deletion will make two compositions adjacent | |
524 | and indistinguishable when they have same (eq) property. | |
525 | To avoid it, in such a case, we change the property of | |
526 | the former to the copy of it. */ | |
527 | if (to < end) | |
528 | Fput_text_property (make_number (start), make_number (to), | |
529 | Qcomposition, | |
530 | Fcons (XCAR (prop), XCDR (prop)), Qnil); | |
531 | run_composition_function (start, end, prop); | |
532 | } | |
533 | else if (to < ZV | |
534 | && find_composition (to, -1, &start, &end, &prop, Qnil)) | |
535 | run_composition_function (start, end, prop); | |
536 | } | |
537 | } | |
538 | ||
c1361885 KH |
539 | |
540 | /* Modify composition property values in LIST destructively. LIST is | |
541 | a list as returned from text_property_list. Change values to the | |
542 | top-level copies of them so that none of them are `eq'. */ | |
543 | ||
544 | void | |
545 | make_composition_value_copy (list) | |
546 | Lisp_Object list; | |
547 | { | |
548 | Lisp_Object plist, val; | |
549 | ||
550 | for (; CONSP (list); list = XCDR (list)) | |
551 | { | |
552 | plist = XCAR (XCDR (XCDR (XCAR (list)))); | |
553 | while (CONSP (plist) && CONSP (XCDR (plist))) | |
554 | { | |
555 | if (EQ (XCAR (plist), Qcomposition) | |
556 | && (val = XCAR (XCDR (plist)), CONSP (val))) | |
557 | XCAR (XCDR (plist)) = Fcons (XCAR (val), XCDR (val)); | |
558 | plist = XCDR (XCDR (plist)); | |
559 | } | |
560 | } | |
561 | } | |
562 | ||
563 | ||
ca4c9455 KH |
564 | /* Make text in the region between START and END a composition that |
565 | has COMPONENTS and MODIFICATION-FUNC. | |
566 | ||
567 | If STRING is non-nil, then operate on characters contained between | |
568 | indices START and END in STRING. */ | |
569 | ||
570 | void | |
571 | compose_text (start, end, components, modification_func, string) | |
572 | int start, end; | |
573 | Lisp_Object components, modification_func, string; | |
574 | { | |
575 | Lisp_Object prop; | |
576 | ||
577 | prop = Fcons (Fcons (make_number (end - start), components), | |
578 | modification_func); | |
579 | Fput_text_property (make_number (start), make_number (end), | |
580 | Qcomposition, prop, string); | |
581 | } | |
582 | ||
40add26d KH |
583 | /* Compose sequences of characters in the region between START and END |
584 | by functions registered in Vcomposition_function_table. If STRING | |
585 | is non-nil, operate on characters contained between indices START | |
586 | and END in STRING. */ | |
587 | ||
588 | void | |
589 | compose_chars_in_text (start, end, string) | |
590 | int start, end; | |
591 | Lisp_Object string; | |
592 | { | |
593 | int count; | |
594 | struct gcpro gcpro1; | |
595 | Lisp_Object tail, elt, val, to; | |
596 | /* Set to nonzero if we don't have to compose ASCII characters. */ | |
597 | int skip_ascii; | |
598 | int i, len, stop, c; | |
599 | unsigned char *ptr, *pend; | |
600 | ||
601 | if (! CHAR_TABLE_P (Vcomposition_function_table)) | |
602 | return; | |
603 | ||
604 | if (STRINGP (string)) | |
605 | { | |
606 | count = specpdl_ptr - specpdl; | |
607 | GCPRO1 (string); | |
608 | stop = end; | |
609 | ptr = XSTRING (string)->data + string_char_to_byte (string, start); | |
610 | pend = ptr + STRING_BYTES (XSTRING (string)); | |
611 | } | |
612 | else | |
613 | { | |
614 | record_unwind_protect (save_excursion_restore, save_excursion_save ()); | |
615 | TEMP_SET_PT (start); | |
616 | stop = (start < GPT && GPT < end ? GPT : end); | |
617 | ptr = CHAR_POS_ADDR (start); | |
618 | pend = CHAR_POS_ADDR (end); | |
619 | } | |
620 | ||
621 | /* Preserve the match data. */ | |
622 | record_unwind_protect (Fset_match_data, Fmatch_data (Qnil, Qnil)); | |
623 | ||
624 | /* If none of ASCII characters have composition functions, we can | |
625 | skip them quickly. */ | |
626 | for (i = 0; i < 128; i++) | |
627 | if (!NILP (CHAR_TABLE_REF (Vcomposition_function_table, i))) | |
628 | break; | |
629 | skip_ascii = (i == 128); | |
630 | ||
631 | ||
632 | while (1) | |
633 | { | |
634 | if (skip_ascii) | |
635 | while (start < stop && ASCII_BYTE_P (*ptr)) | |
636 | start++, ptr++; | |
637 | ||
638 | if (start >= stop) | |
639 | { | |
640 | if (stop == end || start >= end) | |
641 | break; | |
642 | stop = end; | |
643 | if (STRINGP (string)) | |
644 | ptr = XSTRING (string)->data + string_char_to_byte (string, start); | |
645 | else | |
646 | ptr = CHAR_POS_ADDR (start); | |
647 | } | |
648 | ||
649 | c = STRING_CHAR_AND_LENGTH (ptr, pend - ptr, len); | |
650 | tail = CHAR_TABLE_REF (Vcomposition_function_table, c); | |
651 | while (CONSP (tail)) | |
652 | { | |
653 | elt = XCAR (tail); | |
654 | if (CONSP (elt) | |
655 | && STRINGP (XCAR (elt)) | |
656 | && !NILP (Ffboundp (XCDR (elt)))) | |
657 | { | |
658 | if (STRINGP (string)) | |
659 | val = Fstring_match (XCAR (elt), string, make_number (start)); | |
660 | else | |
661 | { | |
662 | val = Flooking_at (XCAR (elt)); | |
663 | if (!NILP (val)) | |
664 | val = make_number (start); | |
665 | } | |
666 | if (INTEGERP (val) && XFASTINT (val) == start) | |
667 | { | |
668 | to = Fmatch_end (make_number (0)); | |
669 | val = call4 (XCDR (elt), val, to, XCAR (elt), string); | |
670 | if (INTEGERP (val) && XINT (val) > 1) | |
671 | { | |
672 | start += XINT (val); | |
673 | if (STRINGP (string)) | |
674 | ptr = XSTRING (string)->data + string_char_to_byte (string, start); | |
675 | else | |
676 | ptr = CHAR_POS_ADDR (start); | |
677 | } | |
678 | else | |
679 | { | |
680 | start++; | |
681 | ptr += len; | |
682 | } | |
683 | break; | |
684 | } | |
685 | } | |
686 | tail = XCDR (tail); | |
687 | } | |
688 | if (!CONSP (tail)) | |
689 | { | |
690 | /* No composition done. Try the next character. */ | |
691 | start++; | |
692 | ptr += len; | |
693 | } | |
694 | } | |
695 | ||
696 | unbind_to (count, Qnil); | |
697 | if (STRINGP (string)) | |
698 | UNGCPRO; | |
699 | } | |
ca4c9455 KH |
700 | \f |
701 | /* Emacs Lisp APIs. */ | |
702 | ||
703 | DEFUN ("compose-region-internal", Fcompose_region_internal, | |
704 | Scompose_region_internal, 2, 4, 0, | |
705 | "Internal use only.\n\ | |
706 | \n\ | |
707 | Compose text in the region between START and END.\n\ | |
708 | Optional 3rd and 4th arguments are COMPONENTS and MODIFICATION-FUNC\n\ | |
709 | for the composition. See `compose-region' for more detial.") | |
710 | (start, end, components, mod_func) | |
711 | Lisp_Object start, end, components, mod_func; | |
712 | { | |
713 | validate_region (&start, &end); | |
714 | if (!NILP (components) | |
715 | && !INTEGERP (components) | |
716 | && !CONSP (components) | |
717 | && !STRINGP (components)) | |
718 | CHECK_VECTOR (components, 2); | |
719 | ||
720 | compose_text (XINT (start), XINT (end), components, mod_func, Qnil); | |
721 | return Qnil; | |
722 | } | |
723 | ||
724 | DEFUN ("compose-string-internal", Fcompose_string_internal, | |
725 | Scompose_string_internal, 3, 5, 0, | |
726 | "Internal use only.\n\ | |
727 | \n\ | |
728 | Compose text between indices START and END of STRING.\n\ | |
729 | Optional 4th and 5th arguments are COMPONENTS and MODIFICATION-FUNC\n\ | |
730 | for the composition. See `compose-string' for more detial.") | |
731 | (string, start, end, components, mod_func) | |
732 | Lisp_Object string, start, end, components, mod_func; | |
733 | { | |
734 | CHECK_STRING (string, 0); | |
735 | CHECK_NUMBER (start, 1); | |
736 | CHECK_NUMBER (end, 2); | |
737 | ||
738 | if (XINT (start) < 0 || | |
739 | XINT (start) > XINT (end) | |
740 | || XINT (end) > XSTRING (string)->size) | |
741 | args_out_of_range (start, end); | |
742 | ||
743 | compose_text (XINT (start), XINT (end), components, mod_func, string); | |
744 | return string; | |
745 | } | |
746 | ||
747 | DEFUN ("find-composition-internal", Ffind_composition_internal, | |
748 | Sfind_composition_internal, 4, 4, 0, | |
749 | "Internal use only.\n\ | |
750 | \n\ | |
751 | Return information about composition at or nearest to position POS.\n\ | |
752 | See `find-composition' for more detail.") | |
753 | (pos, limit, string, detail_p) | |
754 | Lisp_Object pos, limit, string, detail_p; | |
755 | { | |
756 | Lisp_Object prop, tail; | |
757 | int start, end; | |
758 | int id; | |
759 | ||
760 | CHECK_NUMBER_COERCE_MARKER (pos, 0); | |
761 | start = XINT (pos); | |
762 | if (!NILP (limit)) | |
763 | { | |
764 | CHECK_NUMBER_COERCE_MARKER (limit, 1); | |
765 | end = XINT (limit); | |
766 | } | |
767 | else | |
768 | end = -1; | |
769 | if (!NILP (string)) | |
770 | CHECK_STRING (string, 2); | |
771 | ||
772 | if (!find_composition (start, end, &start, &end, &prop, string)) | |
773 | return Qnil; | |
774 | if (!COMPOSITION_VALID_P (start, end, prop)) | |
775 | return Fcons (make_number (start), Fcons (make_number (end), | |
776 | Fcons (Qnil, Qnil))); | |
777 | if (NILP (detail_p)) | |
778 | return Fcons (make_number (start), Fcons (make_number (end), | |
779 | Fcons (Qt, Qnil))); | |
780 | ||
781 | if (COMPOSITION_REGISTERD_P (prop)) | |
782 | id = COMPOSITION_ID (prop); | |
783 | else | |
784 | { | |
785 | int start_byte = (NILP (string) | |
786 | ? CHAR_TO_BYTE (start) | |
787 | : string_char_to_byte (string, start)); | |
788 | id = get_composition_id (start, start_byte, end - start, prop, string); | |
789 | } | |
790 | ||
791 | if (id >= 0) | |
792 | { | |
793 | Lisp_Object components, relative_p, mod_func; | |
794 | enum composition_method method = COMPOSITION_METHOD (prop); | |
795 | int width = composition_table[id]->width; | |
796 | ||
797 | components = Fcopy_sequence (COMPOSITION_COMPONENTS (prop)); | |
798 | relative_p = (method == COMPOSITION_WITH_RULE_ALTCHARS | |
799 | ? Qnil : Qt); | |
800 | mod_func = COMPOSITION_MODIFICATION_FUNC (prop); | |
801 | tail = Fcons (components, | |
802 | Fcons (relative_p, | |
803 | Fcons (mod_func, | |
804 | Fcons (make_number (width), Qnil)))); | |
805 | } | |
806 | else | |
807 | tail = Qnil; | |
808 | ||
809 | return Fcons (make_number (start), Fcons (make_number (end), tail)); | |
810 | } | |
811 | ||
812 | \f | |
813 | void | |
814 | syms_of_composite () | |
815 | { | |
816 | Qcomposition = intern ("composition"); | |
817 | staticpro (&Qcomposition); | |
818 | ||
819 | /* Make a hash table for composition. */ | |
820 | { | |
09654086 | 821 | Lisp_Object args[6]; |
ca4c9455 KH |
822 | extern Lisp_Object QCsize; |
823 | ||
824 | args[0] = QCtest; | |
825 | args[1] = Qequal; | |
826 | args[2] = QCweakness; | |
827 | args[3] = Qnil; | |
828 | args[4] = QCsize; | |
829 | args[5] = make_number (311); | |
09654086 | 830 | composition_hash_table = Fmake_hash_table (6, args); |
ca4c9455 KH |
831 | staticpro (&composition_hash_table); |
832 | } | |
833 | ||
834 | /* Text property `composition' should be nonsticky by default. */ | |
835 | Vtext_property_default_nonsticky | |
836 | = Fcons (Fcons (Qcomposition, Qt), Vtext_property_default_nonsticky); | |
837 | ||
838 | DEFVAR_LISP ("compose-chars-after-function", &Vcompose_chars_after_function, | |
839 | "Function to adjust composition of buffer text.\n\ | |
840 | \n\ | |
40add26d KH |
841 | The function is called with three arguments FROM, TO, and OBJECT.\n\ |
842 | FROM and TO specify the range of text of which composition should be\n\ | |
843 | adjusted. OBJECT, if non-nil, is a string that contains the text.\n\ | |
844 | \n\ | |
ca4c9455 KH |
845 | This function is called after a text with `composition' property is\n\ |
846 | inserted or deleted to keep `composition' property of buffer text\n\ | |
847 | valid.\n\ | |
848 | \n\ | |
ca4c9455 KH |
849 | The default value is the function `compose-chars-after'."); |
850 | Vcompose_chars_after_function = intern ("compose-chars-after"); | |
851 | ||
40add26d KH |
852 | Qcomposition_function_table = intern ("composition-function-table"); |
853 | staticpro (&Qcomposition_function_table); | |
854 | ||
855 | /* Intern this now in case it isn't already done. | |
856 | Setting this variable twice is harmless. | |
857 | But don't staticpro it here--that is done in alloc.c. */ | |
858 | Qchar_table_extra_slots = intern ("char-table-extra-slots"); | |
859 | ||
860 | Fput (Qcomposition_function_table, Qchar_table_extra_slots, make_number (0)); | |
861 | ||
862 | DEFVAR_LISP ("composition-function-table", &Vcomposition_function_table, | |
863 | "Char table of patterns and functions to make a composition.\n\ | |
864 | \n\ | |
865 | Each element is nil or an alist of PATTERNs vs FUNCs, where PATTERNs\n\ | |
866 | are regular expressions and FUNCs are functions. FUNC is responsible\n\ | |
867 | for composing text matching the corresponding PATTERN. FUNC is called\n\ | |
868 | with three arguments FROM, TO, and PATTERN. See the function\n\ | |
869 | `compose-chars-after' for more detail.\n\ | |
870 | \n\ | |
871 | This table is looked up by the first character of a composition when\n\ | |
872 | the composition gets invalid after a change in a buffer."); | |
873 | Vcomposition_function_table | |
874 | = Fmake_char_table (Qcomposition_function_table, Qnil); | |
875 | ||
ca4c9455 KH |
876 | defsubr (&Scompose_region_internal); |
877 | defsubr (&Scompose_string_internal); | |
878 | defsubr (&Sfind_composition_internal); | |
879 | } |