Commit | Line | Data |
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ca4c9455 KH |
1 | /* Composite sequence support. |
2 | Copyright (C) 1999 Electrotechnical Laboratory, JAPAN. | |
3 | Licensed to the Free Software Foundation. | |
72632c83 | 4 | Copyright (C) 2001 Free Software Foundation, Inc. |
ca4c9455 KH |
5 | |
6 | This file is part of GNU Emacs. | |
7 | ||
8 | GNU Emacs is free software; you can redistribute it and/or modify | |
9 | it under the terms of the GNU General Public License as published by | |
10 | the Free Software Foundation; either version 2, or (at your option) | |
11 | any later version. | |
12 | ||
13 | GNU Emacs is distributed in the hope that it will be useful, | |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
19 | along with GNU Emacs; see the file COPYING. If not, write to | |
4fc5845f LK |
20 | the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
21 | Boston, MA 02110-1301, USA. */ | |
ca4c9455 KH |
22 | |
23 | #include <config.h> | |
24 | #include "lisp.h" | |
25 | #include "buffer.h" | |
26 | #include "charset.h" | |
27 | #include "intervals.h" | |
28 | ||
29 | /* Emacs uses special text property `composition' to support character | |
30 | composition. A sequence of characters that have the same (i.e. eq) | |
31 | `composition' property value is treated as a single composite | |
32 | sequence (we call it just `composition' here after). Characters in | |
33 | a composition are all composed somehow on the screen. | |
34 | ||
35 | The property value has this form when the composition is made: | |
36 | ((LENGTH . COMPONENTS) . MODIFICATION-FUNC) | |
37 | then turns to this form: | |
38 | (COMPOSITION-ID . (LENGTH COMPONENTS-VEC . MODIFICATION-FUNC)) | |
39 | when the composition is registered in composition_hash_table and | |
40 | composition_table. These rather peculiar structures were designed | |
41 | to make it easy to distinguish them quickly (we can do that by | |
42 | checking only the first element) and to extract LENGTH (from the | |
43 | former form) and COMPOSITION-ID (from the latter form). | |
44 | ||
45 | We register a composition when it is displayed, or when the width | |
46 | is required (for instance, to calculate columns). | |
47 | ||
48 | LENGTH -- Length of the composition. This information is used to | |
49 | check the validity of the composition. | |
50 | ||
51 | COMPONENTS -- Character, string, vector, list, or nil. | |
52 | ||
53 | If it is nil, characters in the text are composed relatively | |
54 | according to their metrics in font glyphs. | |
55 | ||
56 | If it is a character or a string, the character or characters | |
57 | in the string are composed relatively. | |
58 | ||
59 | If it is a vector or list of integers, the element is a | |
60 | character or an encoded composition rule. The characters are | |
61 | composed according to the rules. (2N)th elements are | |
62 | characters to be composed and (2N+1)th elements are | |
63 | composition rules to tell how to compose (2N+2)th element with | |
64 | the previously composed 2N glyphs. | |
65 | ||
66 | COMPONENTS-VEC -- Vector of integers. In relative composition, the | |
67 | elements are characters to be composed. In rule-base | |
68 | composition, the elements are characters or encoded | |
69 | composition rules. | |
70 | ||
71 | MODIFICATION-FUNC -- If non nil, it is a function to call when the | |
72 | composition gets invalid after a modification in a buffer. If | |
73 | it is nil, a function in `composition-function-table' of the | |
74 | first character in the sequence is called. | |
75 | ||
76 | COMPOSITION-ID --Identification number of the composition. It is | |
77 | used as an index to composition_table for the composition. | |
78 | ||
79 | When Emacs has to display a composition or has to know its | |
80 | displaying width, the function get_composition_id is called. It | |
81 | returns COMPOSITION-ID so that the caller can access the | |
82 | information about the composition through composition_table. If a | |
83 | COMPOSITION-ID has not yet been assigned to the composition, | |
84 | get_composition_id checks the validity of `composition' property, | |
85 | and, if valid, assigns a new ID, registers the information in | |
86 | composition_hash_table and composition_table, and changes the form | |
87 | of the property value. If the property is invalid, return -1 | |
88 | without changing the property value. | |
89 | ||
90 | We use two tables to keep information about composition; | |
91 | composition_hash_table and composition_table. | |
92 | ||
93 | The former is a hash table in which keys are COMPONENTS-VECs and | |
94 | values are the corresponding COMPOSITION-IDs. This hash table is | |
4abc7470 | 95 | weak, but as each key (COMPONENTS-VEC) is also kept as a value of the |
ca4c9455 | 96 | `composition' property, it won't be collected as garbage until all |
4abc7470 | 97 | bits of text that have the same COMPONENTS-VEC are deleted. |
ca4c9455 KH |
98 | |
99 | The latter is a table of pointers to `struct composition' indexed | |
4abc7470 | 100 | by COMPOSITION-ID. This structure keeps the other information (see |
ca4c9455 KH |
101 | composite.h). |
102 | ||
103 | In general, a text property holds information about individual | |
104 | characters. But, a `composition' property holds information about | |
4abc7470 | 105 | a sequence of characters (in this sense, it is like the `intangible' |
ca4c9455 | 106 | property). That means that we should not share the property value |
4abc7470 | 107 | in adjacent compositions -- we can't distinguish them if they have the |
ca4c9455 KH |
108 | same property. So, after any changes, we call |
109 | `update_compositions' and change a property of one of adjacent | |
110 | compositions to a copy of it. This function also runs a proper | |
111 | composition modification function to make a composition that gets | |
112 | invalid by the change valid again. | |
113 | ||
4abc7470 | 114 | As the value of the `composition' property holds information about a |
ca4c9455 | 115 | specific range of text, the value gets invalid if we change the |
4abc7470 | 116 | text in the range. We treat the `composition' property as always |
ca4c9455 KH |
117 | rear-nonsticky (currently by setting default-text-properties to |
118 | (rear-nonsticky (composition))) and we never make properties of | |
119 | adjacent compositions identical. Thus, any such changes make the | |
4abc7470 | 120 | range just shorter. So, we can check the validity of the `composition' |
ca4c9455 KH |
121 | property by comparing LENGTH information with the actual length of |
122 | the composition. | |
123 | ||
124 | */ | |
125 | ||
126 | ||
127 | Lisp_Object Qcomposition; | |
128 | ||
129 | /* Table of pointers to the structure `composition' indexed by | |
130 | COMPOSITION-ID. This structure is for storing information about | |
131 | each composition except for COMPONENTS-VEC. */ | |
132 | struct composition **composition_table; | |
133 | ||
134 | /* The current size of `composition_table'. */ | |
135 | static int composition_table_size; | |
136 | ||
137 | /* Number of compositions currently made. */ | |
138 | int n_compositions; | |
139 | ||
140 | /* Hash table for compositions. The key is COMPONENTS-VEC of | |
141 | `composition' property. The value is the corresponding | |
142 | COMPOSITION-ID. */ | |
143 | Lisp_Object composition_hash_table; | |
144 | ||
145 | /* Function to call to adjust composition. */ | |
146 | Lisp_Object Vcompose_chars_after_function; | |
147 | ||
40add26d KH |
148 | /* Char-table of patterns and functions to make a composition. */ |
149 | Lisp_Object Vcomposition_function_table; | |
150 | Lisp_Object Qcomposition_function_table; | |
151 | ||
ca4c9455 KH |
152 | /* Temporary variable used in macros COMPOSITION_XXX. */ |
153 | Lisp_Object composition_temp; | |
154 | \f | |
155 | /* Return how many columns C will occupy on the screen. It always | |
156 | returns 1 for control characters and 8-bit characters because those | |
157 | are just ignored in a composition. */ | |
158 | #define CHAR_WIDTH(c) \ | |
159 | (SINGLE_BYTE_CHAR_P (c) ? 1 : CHARSET_WIDTH (CHAR_CHARSET (c))) | |
160 | ||
ca4c9455 KH |
161 | /* Return COMPOSITION-ID of a composition at buffer position |
162 | CHARPOS/BYTEPOS and length NCHARS. The `composition' property of | |
163 | the sequence is PROP. STRING, if non-nil, is a string that | |
164 | contains the composition instead of the current buffer. | |
165 | ||
166 | If the composition is invalid, return -1. */ | |
167 | ||
168 | int | |
169 | get_composition_id (charpos, bytepos, nchars, prop, string) | |
170 | int charpos, bytepos, nchars; | |
171 | Lisp_Object prop, string; | |
172 | { | |
173 | Lisp_Object id, length, components, key, *key_contents; | |
174 | int glyph_len; | |
175 | struct Lisp_Hash_Table *hash_table = XHASH_TABLE (composition_hash_table); | |
176 | int hash_index; | |
177 | unsigned hash_code; | |
178 | struct composition *cmp; | |
179 | int i, ch; | |
180 | ||
181 | /* PROP should be | |
182 | Form-A: ((LENGTH . COMPONENTS) . MODIFICATION-FUNC) | |
183 | or | |
184 | Form-B: (COMPOSITION-ID . (LENGTH COMPONENTS-VEC . MODIFICATION-FUNC)) | |
185 | */ | |
186 | if (nchars == 0 || !CONSP (prop)) | |
187 | goto invalid_composition; | |
188 | ||
189 | id = XCAR (prop); | |
190 | if (INTEGERP (id)) | |
191 | { | |
192 | /* PROP should be Form-B. */ | |
193 | if (XINT (id) < 0 || XINT (id) >= n_compositions) | |
194 | goto invalid_composition; | |
195 | return XINT (id); | |
196 | } | |
197 | ||
198 | /* PROP should be Form-A. | |
199 | Thus, ID should be (LENGTH . COMPONENTS). */ | |
200 | if (!CONSP (id)) | |
201 | goto invalid_composition; | |
202 | length = XCAR (id); | |
203 | if (!INTEGERP (length) || XINT (length) != nchars) | |
204 | goto invalid_composition; | |
205 | ||
206 | components = XCDR (id); | |
207 | ||
208 | /* Check if the same composition has already been registered or not | |
209 | by consulting composition_hash_table. The key for this table is | |
210 | COMPONENTS (converted to a vector COMPONENTS-VEC) or, if it is | |
211 | nil, vector of characters in the composition range. */ | |
212 | if (INTEGERP (components)) | |
213 | key = Fmake_vector (make_number (1), components); | |
214 | else if (STRINGP (components) || CONSP (components)) | |
215 | key = Fvconcat (1, &components); | |
216 | else if (VECTORP (components)) | |
217 | key = components; | |
218 | else if (NILP (components)) | |
219 | { | |
220 | key = Fmake_vector (make_number (nchars), Qnil); | |
221 | if (STRINGP (string)) | |
222 | for (i = 0; i < nchars; i++) | |
223 | { | |
224 | FETCH_STRING_CHAR_ADVANCE (ch, string, charpos, bytepos); | |
225 | XVECTOR (key)->contents[i] = make_number (ch); | |
226 | } | |
227 | else | |
228 | for (i = 0; i < nchars; i++) | |
229 | { | |
230 | FETCH_CHAR_ADVANCE (ch, charpos, bytepos); | |
231 | XVECTOR (key)->contents[i] = make_number (ch); | |
232 | } | |
233 | } | |
234 | else | |
235 | goto invalid_composition; | |
236 | ||
237 | hash_index = hash_lookup (hash_table, key, &hash_code); | |
238 | if (hash_index >= 0) | |
239 | { | |
240 | /* We have already registered the same composition. Change PROP | |
241 | from Form-A above to Form-B while replacing COMPONENTS with | |
242 | COMPONENTS-VEC stored in the hash table. We can directly | |
243 | modify the cons cell of PROP because it is not shared. */ | |
244 | key = HASH_KEY (hash_table, hash_index); | |
245 | id = HASH_VALUE (hash_table, hash_index); | |
f3fbd155 KR |
246 | XSETCAR (prop, id); |
247 | XSETCDR (prop, Fcons (make_number (nchars), Fcons (key, XCDR (prop)))); | |
ca4c9455 KH |
248 | return XINT (id); |
249 | } | |
250 | ||
251 | /* This composition is a new one. We must register it. */ | |
177c0ea7 | 252 | |
ca4c9455 KH |
253 | /* Check if we have sufficient memory to store this information. */ |
254 | if (composition_table_size == 0) | |
255 | { | |
256 | composition_table_size = 256; | |
257 | composition_table | |
258 | = (struct composition **) xmalloc (sizeof (composition_table[0]) | |
259 | * composition_table_size); | |
260 | } | |
261 | else if (composition_table_size <= n_compositions) | |
262 | { | |
263 | composition_table_size += 256; | |
264 | composition_table | |
265 | = (struct composition **) xrealloc (composition_table, | |
266 | sizeof (composition_table[0]) | |
267 | * composition_table_size); | |
268 | } | |
269 | ||
270 | key_contents = XVECTOR (key)->contents; | |
271 | ||
272 | /* Check if the contents of COMPONENTS are valid if COMPONENTS is a | |
273 | vector or a list. It should be a sequence of: | |
274 | char1 rule1 char2 rule2 char3 ... ruleN charN+1 */ | |
275 | if (VECTORP (components) || CONSP (components)) | |
276 | { | |
277 | int len = XVECTOR (key)->size; | |
278 | ||
279 | /* The number of elements should be odd. */ | |
280 | if ((len % 2) == 0) | |
281 | goto invalid_composition; | |
282 | /* All elements should be integers (character or encoded | |
283 | composition rule). */ | |
284 | for (i = 0; i < len; i++) | |
285 | { | |
286 | if (!INTEGERP (key_contents[i])) | |
287 | goto invalid_composition; | |
288 | } | |
289 | } | |
290 | ||
291 | /* Change PROP from Form-A above to Form-B. We can directly modify | |
292 | the cons cell of PROP because it is not shared. */ | |
293 | XSETFASTINT (id, n_compositions); | |
f3fbd155 KR |
294 | XSETCAR (prop, id); |
295 | XSETCDR (prop, Fcons (make_number (nchars), Fcons (key, XCDR (prop)))); | |
ca4c9455 KH |
296 | |
297 | /* Register the composition in composition_hash_table. */ | |
298 | hash_index = hash_put (hash_table, key, id, hash_code); | |
299 | ||
300 | /* Register the composition in composition_table. */ | |
301 | cmp = (struct composition *) xmalloc (sizeof (struct composition)); | |
302 | ||
303 | cmp->method = (NILP (components) | |
304 | ? COMPOSITION_RELATIVE | |
305 | : ((INTEGERP (components) || STRINGP (components)) | |
306 | ? COMPOSITION_WITH_ALTCHARS | |
307 | : COMPOSITION_WITH_RULE_ALTCHARS)); | |
308 | cmp->hash_index = hash_index; | |
309 | glyph_len = (cmp->method == COMPOSITION_WITH_RULE_ALTCHARS | |
310 | ? (XVECTOR (key)->size + 1) / 2 | |
311 | : XVECTOR (key)->size); | |
312 | cmp->glyph_len = glyph_len; | |
313 | cmp->offsets = (short *) xmalloc (sizeof (short) * glyph_len * 2); | |
314 | cmp->font = NULL; | |
315 | ||
316 | /* Calculate the width of overall glyphs of the composition. */ | |
317 | if (cmp->method != COMPOSITION_WITH_RULE_ALTCHARS) | |
318 | { | |
319 | /* Relative composition. */ | |
320 | cmp->width = 0; | |
321 | for (i = 0; i < glyph_len; i++) | |
322 | { | |
323 | int this_width; | |
324 | ch = XINT (key_contents[i]); | |
325 | this_width = CHAR_WIDTH (ch); | |
326 | if (cmp->width < this_width) | |
327 | cmp->width = this_width; | |
328 | } | |
329 | } | |
330 | else | |
331 | { | |
332 | /* Rule-base composition. */ | |
333 | float leftmost = 0.0, rightmost; | |
334 | ||
335 | ch = XINT (key_contents[0]); | |
336 | rightmost = CHAR_WIDTH (ch); | |
337 | ||
338 | for (i = 1; i < glyph_len; i += 2) | |
339 | { | |
340 | int rule, gref, nref; | |
341 | int this_width; | |
342 | float this_left; | |
343 | ||
344 | rule = XINT (key_contents[i]); | |
345 | ch = XINT (key_contents[i + 1]); | |
346 | this_width = CHAR_WIDTH (ch); | |
347 | ||
348 | /* A composition rule is specified by an integer value | |
349 | that encodes global and new reference points (GREF and | |
350 | NREF). GREF and NREF are specified by numbers as | |
351 | below: | |
352 | 0---1---2 -- ascent | |
353 | | | | |
354 | | | | |
355 | | | | |
356 | 9--10--11 -- center | |
357 | | | | |
358 | ---3---4---5--- baseline | |
359 | | | | |
360 | 6---7---8 -- descent | |
361 | */ | |
362 | COMPOSITION_DECODE_RULE (rule, gref, nref); | |
363 | this_left = (leftmost | |
364 | + (gref % 3) * (rightmost - leftmost) / 2.0 | |
365 | - (nref % 3) * this_width / 2.0); | |
366 | ||
367 | if (this_left < leftmost) | |
368 | leftmost = this_left; | |
369 | if (this_left + this_width > rightmost) | |
370 | rightmost = this_left + this_width; | |
371 | } | |
372 | ||
373 | cmp->width = rightmost - leftmost; | |
374 | if (cmp->width < (rightmost - leftmost)) | |
375 | /* To get a ceiling integer value. */ | |
376 | cmp->width++; | |
377 | } | |
378 | ||
379 | composition_table[n_compositions] = cmp; | |
380 | ||
381 | return n_compositions++; | |
382 | ||
383 | invalid_composition: | |
384 | /* Would it be better to remove this `composition' property? */ | |
385 | return -1; | |
386 | } | |
387 | ||
388 | \f | |
389 | /* Find a composition at or nearest to position POS of OBJECT (buffer | |
390 | or string). | |
391 | ||
392 | OBJECT defaults to the current buffer. If there's a composition at | |
393 | POS, set *START and *END to the start and end of the sequence, | |
394 | *PROP to the `composition' property, and return 1. | |
395 | ||
396 | If there's no composition at POS and LIMIT is negative, return 0. | |
397 | ||
398 | Otherwise, search for a composition forward (LIMIT > POS) or | |
399 | backward (LIMIT < POS). In this case, LIMIT bounds the search. | |
400 | ||
401 | If a composition is found, set *START, *END, and *PROP as above, | |
402 | and return 1, else return 0. | |
403 | ||
404 | This doesn't check the validity of composition. */ | |
405 | ||
406 | int | |
407 | find_composition (pos, limit, start, end, prop, object) | |
408 | int pos, limit, *start, *end; | |
409 | Lisp_Object *prop, object; | |
410 | { | |
411 | Lisp_Object val; | |
412 | ||
413 | if (get_property_and_range (pos, Qcomposition, prop, start, end, object)) | |
414 | return 1; | |
415 | ||
416 | if (limit < 0 || limit == pos) | |
417 | return 0; | |
418 | ||
419 | if (limit > pos) /* search forward */ | |
d279f620 KH |
420 | { |
421 | val = Fnext_single_property_change (make_number (pos), Qcomposition, | |
422 | object, make_number (limit)); | |
423 | pos = XINT (val); | |
424 | if (pos == limit) | |
425 | return 0; | |
426 | } | |
ca4c9455 | 427 | else /* search backward */ |
d279f620 KH |
428 | { |
429 | if (get_property_and_range (pos - 1, Qcomposition, prop, start, end, | |
430 | object)) | |
431 | return 1; | |
432 | val = Fprevious_single_property_change (make_number (pos), Qcomposition, | |
433 | object, make_number (limit)); | |
434 | pos = XINT (val); | |
435 | if (pos == limit) | |
436 | return 0; | |
437 | pos--; | |
438 | } | |
ca4c9455 KH |
439 | get_property_and_range (pos, Qcomposition, prop, start, end, object); |
440 | return 1; | |
441 | } | |
442 | ||
443 | /* Run a proper function to adjust the composition sitting between | |
444 | FROM and TO with property PROP. */ | |
445 | ||
446 | static void | |
447 | run_composition_function (from, to, prop) | |
448 | int from, to; | |
449 | Lisp_Object prop; | |
450 | { | |
7d019510 | 451 | Lisp_Object func; |
ca4c9455 KH |
452 | int start, end; |
453 | ||
454 | func = COMPOSITION_MODIFICATION_FUNC (prop); | |
455 | /* If an invalid composition precedes or follows, try to make them | |
456 | valid too. */ | |
457 | if (from > BEGV | |
458 | && find_composition (from - 1, -1, &start, &end, &prop, Qnil) | |
459 | && !COMPOSITION_VALID_P (start, end, prop)) | |
460 | from = start; | |
461 | if (to < ZV | |
462 | && find_composition (to, -1, &start, &end, &prop, Qnil) | |
463 | && !COMPOSITION_VALID_P (start, end, prop)) | |
464 | to = end; | |
775b3d2d | 465 | if (!NILP (Ffboundp (func))) |
ca4c9455 | 466 | call2 (func, make_number (from), make_number (to)); |
09654086 | 467 | else if (!NILP (Ffboundp (Vcompose_chars_after_function))) |
40add26d KH |
468 | call3 (Vcompose_chars_after_function, |
469 | make_number (from), make_number (to), Qnil); | |
ca4c9455 KH |
470 | } |
471 | ||
472 | /* Make invalid compositions adjacent to or inside FROM and TO valid. | |
473 | CHECK_MASK is bitwise `or' of mask bits defined by macros | |
474 | CHECK_XXX (see the comment in composite.h). | |
475 | ||
476 | This function is called when a buffer text is changed. If the | |
477 | change is deletion, FROM == TO. Otherwise, FROM < TO. */ | |
478 | ||
479 | void | |
480 | update_compositions (from, to, check_mask) | |
1e26d5ef | 481 | int from, to, check_mask; |
ca4c9455 | 482 | { |
7d019510 | 483 | Lisp_Object prop; |
ca4c9455 KH |
484 | int start, end; |
485 | ||
6c1aa7f1 GM |
486 | if (inhibit_modification_hooks) |
487 | return; | |
177c0ea7 | 488 | |
d3f40cbd KH |
489 | /* If FROM and TO are not in a valid range, do nothing. */ |
490 | if (! (BEGV <= from && from <= to && to <= ZV)) | |
491 | return; | |
492 | ||
ca4c9455 KH |
493 | if (check_mask & CHECK_HEAD) |
494 | { | |
495 | /* FROM should be at composition boundary. But, insertion or | |
496 | deletion will make two compositions adjacent and | |
497 | indistinguishable when they have same (eq) property. To | |
498 | avoid it, in such a case, we change the property of the | |
499 | latter to the copy of it. */ | |
500 | if (from > BEGV | |
501 | && find_composition (from - 1, -1, &start, &end, &prop, Qnil)) | |
502 | { | |
503 | if (from < end) | |
504 | Fput_text_property (make_number (from), make_number (end), | |
505 | Qcomposition, | |
506 | Fcons (XCAR (prop), XCDR (prop)), Qnil); | |
507 | run_composition_function (start, end, prop); | |
508 | from = end; | |
509 | } | |
dd33cc56 | 510 | else if (from < ZV |
ca4c9455 KH |
511 | && find_composition (from, -1, &start, &from, &prop, Qnil)) |
512 | run_composition_function (start, from, prop); | |
513 | } | |
514 | ||
515 | if (check_mask & CHECK_INSIDE) | |
516 | { | |
517 | /* In this case, we are sure that (check & CHECK_TAIL) is also | |
518 | nonzero. Thus, here we should check only compositions before | |
519 | (to - 1). */ | |
520 | while (from < to - 1 | |
521 | && find_composition (from, to, &start, &from, &prop, Qnil) | |
522 | && from < to - 1) | |
523 | run_composition_function (start, from, prop); | |
524 | } | |
525 | ||
526 | if (check_mask & CHECK_TAIL) | |
527 | { | |
528 | if (from < to | |
529 | && find_composition (to - 1, -1, &start, &end, &prop, Qnil)) | |
530 | { | |
531 | /* TO should be also at composition boundary. But, | |
532 | insertion or deletion will make two compositions adjacent | |
533 | and indistinguishable when they have same (eq) property. | |
534 | To avoid it, in such a case, we change the property of | |
535 | the former to the copy of it. */ | |
536 | if (to < end) | |
537 | Fput_text_property (make_number (start), make_number (to), | |
538 | Qcomposition, | |
539 | Fcons (XCAR (prop), XCDR (prop)), Qnil); | |
540 | run_composition_function (start, end, prop); | |
541 | } | |
542 | else if (to < ZV | |
543 | && find_composition (to, -1, &start, &end, &prop, Qnil)) | |
544 | run_composition_function (start, end, prop); | |
545 | } | |
546 | } | |
547 | ||
c1361885 KH |
548 | |
549 | /* Modify composition property values in LIST destructively. LIST is | |
550 | a list as returned from text_property_list. Change values to the | |
551 | top-level copies of them so that none of them are `eq'. */ | |
552 | ||
553 | void | |
554 | make_composition_value_copy (list) | |
555 | Lisp_Object list; | |
556 | { | |
557 | Lisp_Object plist, val; | |
558 | ||
559 | for (; CONSP (list); list = XCDR (list)) | |
560 | { | |
561 | plist = XCAR (XCDR (XCDR (XCAR (list)))); | |
562 | while (CONSP (plist) && CONSP (XCDR (plist))) | |
563 | { | |
564 | if (EQ (XCAR (plist), Qcomposition) | |
565 | && (val = XCAR (XCDR (plist)), CONSP (val))) | |
f3fbd155 | 566 | XSETCAR (XCDR (plist), Fcons (XCAR (val), XCDR (val))); |
c1361885 KH |
567 | plist = XCDR (XCDR (plist)); |
568 | } | |
569 | } | |
570 | } | |
571 | ||
572 | ||
ca4c9455 KH |
573 | /* Make text in the region between START and END a composition that |
574 | has COMPONENTS and MODIFICATION-FUNC. | |
575 | ||
576 | If STRING is non-nil, then operate on characters contained between | |
577 | indices START and END in STRING. */ | |
578 | ||
579 | void | |
580 | compose_text (start, end, components, modification_func, string) | |
581 | int start, end; | |
582 | Lisp_Object components, modification_func, string; | |
583 | { | |
584 | Lisp_Object prop; | |
585 | ||
586 | prop = Fcons (Fcons (make_number (end - start), components), | |
587 | modification_func); | |
588 | Fput_text_property (make_number (start), make_number (end), | |
589 | Qcomposition, prop, string); | |
590 | } | |
591 | ||
40add26d KH |
592 | /* Compose sequences of characters in the region between START and END |
593 | by functions registered in Vcomposition_function_table. If STRING | |
594 | is non-nil, operate on characters contained between indices START | |
595 | and END in STRING. */ | |
596 | ||
597 | void | |
598 | compose_chars_in_text (start, end, string) | |
599 | int start, end; | |
600 | Lisp_Object string; | |
601 | { | |
6c1aa7f1 | 602 | int count = 0; |
40add26d KH |
603 | struct gcpro gcpro1; |
604 | Lisp_Object tail, elt, val, to; | |
605 | /* Set to nonzero if we don't have to compose ASCII characters. */ | |
606 | int skip_ascii; | |
607 | int i, len, stop, c; | |
c6fac61f | 608 | const unsigned char *ptr, *pend; |
40add26d KH |
609 | |
610 | if (! CHAR_TABLE_P (Vcomposition_function_table)) | |
611 | return; | |
612 | ||
613 | if (STRINGP (string)) | |
614 | { | |
aed13378 | 615 | count = SPECPDL_INDEX (); |
40add26d KH |
616 | GCPRO1 (string); |
617 | stop = end; | |
d5db4077 KR |
618 | ptr = SDATA (string) + string_char_to_byte (string, start); |
619 | pend = ptr + SBYTES (string); | |
40add26d KH |
620 | } |
621 | else | |
622 | { | |
623 | record_unwind_protect (save_excursion_restore, save_excursion_save ()); | |
624 | TEMP_SET_PT (start); | |
625 | stop = (start < GPT && GPT < end ? GPT : end); | |
626 | ptr = CHAR_POS_ADDR (start); | |
627 | pend = CHAR_POS_ADDR (end); | |
628 | } | |
629 | ||
630 | /* Preserve the match data. */ | |
89f2614d | 631 | record_unwind_save_match_data (); |
40add26d KH |
632 | |
633 | /* If none of ASCII characters have composition functions, we can | |
634 | skip them quickly. */ | |
635 | for (i = 0; i < 128; i++) | |
636 | if (!NILP (CHAR_TABLE_REF (Vcomposition_function_table, i))) | |
637 | break; | |
638 | skip_ascii = (i == 128); | |
639 | ||
640 | ||
641 | while (1) | |
642 | { | |
643 | if (skip_ascii) | |
644 | while (start < stop && ASCII_BYTE_P (*ptr)) | |
645 | start++, ptr++; | |
646 | ||
647 | if (start >= stop) | |
648 | { | |
649 | if (stop == end || start >= end) | |
650 | break; | |
651 | stop = end; | |
652 | if (STRINGP (string)) | |
d5db4077 | 653 | ptr = SDATA (string) + string_char_to_byte (string, start); |
40add26d KH |
654 | else |
655 | ptr = CHAR_POS_ADDR (start); | |
656 | } | |
657 | ||
658 | c = STRING_CHAR_AND_LENGTH (ptr, pend - ptr, len); | |
659 | tail = CHAR_TABLE_REF (Vcomposition_function_table, c); | |
660 | while (CONSP (tail)) | |
661 | { | |
662 | elt = XCAR (tail); | |
663 | if (CONSP (elt) | |
664 | && STRINGP (XCAR (elt)) | |
665 | && !NILP (Ffboundp (XCDR (elt)))) | |
666 | { | |
667 | if (STRINGP (string)) | |
668 | val = Fstring_match (XCAR (elt), string, make_number (start)); | |
669 | else | |
670 | { | |
671 | val = Flooking_at (XCAR (elt)); | |
672 | if (!NILP (val)) | |
673 | val = make_number (start); | |
674 | } | |
675 | if (INTEGERP (val) && XFASTINT (val) == start) | |
676 | { | |
677 | to = Fmatch_end (make_number (0)); | |
678 | val = call4 (XCDR (elt), val, to, XCAR (elt), string); | |
679 | if (INTEGERP (val) && XINT (val) > 1) | |
680 | { | |
681 | start += XINT (val); | |
682 | if (STRINGP (string)) | |
d5db4077 | 683 | ptr = SDATA (string) + string_char_to_byte (string, start); |
40add26d KH |
684 | else |
685 | ptr = CHAR_POS_ADDR (start); | |
686 | } | |
687 | else | |
688 | { | |
689 | start++; | |
690 | ptr += len; | |
691 | } | |
692 | break; | |
693 | } | |
694 | } | |
695 | tail = XCDR (tail); | |
696 | } | |
697 | if (!CONSP (tail)) | |
698 | { | |
699 | /* No composition done. Try the next character. */ | |
700 | start++; | |
701 | ptr += len; | |
702 | } | |
703 | } | |
704 | ||
705 | unbind_to (count, Qnil); | |
706 | if (STRINGP (string)) | |
707 | UNGCPRO; | |
708 | } | |
ca4c9455 KH |
709 | \f |
710 | /* Emacs Lisp APIs. */ | |
711 | ||
712 | DEFUN ("compose-region-internal", Fcompose_region_internal, | |
713 | Scompose_region_internal, 2, 4, 0, | |
335c5470 PJ |
714 | doc: /* Internal use only. |
715 | ||
716 | Compose text in the region between START and END. | |
717 | Optional 3rd and 4th arguments are COMPONENTS and MODIFICATION-FUNC | |
9baf7418 | 718 | for the composition. See `compose-region' for more detail. */) |
335c5470 | 719 | (start, end, components, mod_func) |
ca4c9455 KH |
720 | Lisp_Object start, end, components, mod_func; |
721 | { | |
722 | validate_region (&start, &end); | |
723 | if (!NILP (components) | |
724 | && !INTEGERP (components) | |
725 | && !CONSP (components) | |
726 | && !STRINGP (components)) | |
b7826503 | 727 | CHECK_VECTOR (components); |
ca4c9455 KH |
728 | |
729 | compose_text (XINT (start), XINT (end), components, mod_func, Qnil); | |
730 | return Qnil; | |
731 | } | |
732 | ||
733 | DEFUN ("compose-string-internal", Fcompose_string_internal, | |
734 | Scompose_string_internal, 3, 5, 0, | |
335c5470 PJ |
735 | doc: /* Internal use only. |
736 | ||
737 | Compose text between indices START and END of STRING. | |
738 | Optional 4th and 5th arguments are COMPONENTS and MODIFICATION-FUNC | |
9baf7418 | 739 | for the composition. See `compose-string' for more detail. */) |
335c5470 | 740 | (string, start, end, components, mod_func) |
ca4c9455 KH |
741 | Lisp_Object string, start, end, components, mod_func; |
742 | { | |
b7826503 PJ |
743 | CHECK_STRING (string); |
744 | CHECK_NUMBER (start); | |
745 | CHECK_NUMBER (end); | |
ca4c9455 KH |
746 | |
747 | if (XINT (start) < 0 || | |
748 | XINT (start) > XINT (end) | |
d5db4077 | 749 | || XINT (end) > SCHARS (string)) |
ca4c9455 KH |
750 | args_out_of_range (start, end); |
751 | ||
752 | compose_text (XINT (start), XINT (end), components, mod_func, string); | |
753 | return string; | |
754 | } | |
755 | ||
756 | DEFUN ("find-composition-internal", Ffind_composition_internal, | |
177c0ea7 | 757 | Sfind_composition_internal, 4, 4, 0, |
335c5470 PJ |
758 | doc: /* Internal use only. |
759 | ||
760 | Return information about composition at or nearest to position POS. | |
761 | See `find-composition' for more detail. */) | |
762 | (pos, limit, string, detail_p) | |
ca4c9455 KH |
763 | Lisp_Object pos, limit, string, detail_p; |
764 | { | |
765 | Lisp_Object prop, tail; | |
766 | int start, end; | |
767 | int id; | |
768 | ||
b7826503 | 769 | CHECK_NUMBER_COERCE_MARKER (pos); |
ca4c9455 KH |
770 | start = XINT (pos); |
771 | if (!NILP (limit)) | |
772 | { | |
b7826503 | 773 | CHECK_NUMBER_COERCE_MARKER (limit); |
ca4c9455 KH |
774 | end = XINT (limit); |
775 | } | |
776 | else | |
777 | end = -1; | |
177c0ea7 | 778 | |
ca4c9455 | 779 | if (!NILP (string)) |
e3b3e327 | 780 | { |
b7826503 | 781 | CHECK_STRING (string); |
d5db4077 | 782 | if (XINT (pos) < 0 || XINT (pos) > SCHARS (string)) |
e3b3e327 GM |
783 | args_out_of_range (string, pos); |
784 | } | |
785 | else | |
786 | { | |
fa9090b8 | 787 | if (XINT (pos) < BEGV || XINT (pos) > ZV) |
e3b3e327 GM |
788 | args_out_of_range (Fcurrent_buffer (), pos); |
789 | } | |
ca4c9455 KH |
790 | |
791 | if (!find_composition (start, end, &start, &end, &prop, string)) | |
792 | return Qnil; | |
793 | if (!COMPOSITION_VALID_P (start, end, prop)) | |
794 | return Fcons (make_number (start), Fcons (make_number (end), | |
795 | Fcons (Qnil, Qnil))); | |
796 | if (NILP (detail_p)) | |
797 | return Fcons (make_number (start), Fcons (make_number (end), | |
798 | Fcons (Qt, Qnil))); | |
799 | ||
800 | if (COMPOSITION_REGISTERD_P (prop)) | |
801 | id = COMPOSITION_ID (prop); | |
802 | else | |
803 | { | |
804 | int start_byte = (NILP (string) | |
805 | ? CHAR_TO_BYTE (start) | |
806 | : string_char_to_byte (string, start)); | |
807 | id = get_composition_id (start, start_byte, end - start, prop, string); | |
808 | } | |
809 | ||
810 | if (id >= 0) | |
811 | { | |
812 | Lisp_Object components, relative_p, mod_func; | |
813 | enum composition_method method = COMPOSITION_METHOD (prop); | |
814 | int width = composition_table[id]->width; | |
815 | ||
816 | components = Fcopy_sequence (COMPOSITION_COMPONENTS (prop)); | |
817 | relative_p = (method == COMPOSITION_WITH_RULE_ALTCHARS | |
818 | ? Qnil : Qt); | |
819 | mod_func = COMPOSITION_MODIFICATION_FUNC (prop); | |
820 | tail = Fcons (components, | |
821 | Fcons (relative_p, | |
822 | Fcons (mod_func, | |
823 | Fcons (make_number (width), Qnil)))); | |
824 | } | |
825 | else | |
826 | tail = Qnil; | |
827 | ||
828 | return Fcons (make_number (start), Fcons (make_number (end), tail)); | |
829 | } | |
830 | ||
831 | \f | |
832 | void | |
833 | syms_of_composite () | |
834 | { | |
835 | Qcomposition = intern ("composition"); | |
836 | staticpro (&Qcomposition); | |
837 | ||
838 | /* Make a hash table for composition. */ | |
839 | { | |
09654086 | 840 | Lisp_Object args[6]; |
ca4c9455 | 841 | extern Lisp_Object QCsize; |
177c0ea7 | 842 | |
ca4c9455 KH |
843 | args[0] = QCtest; |
844 | args[1] = Qequal; | |
c7211bc5 KH |
845 | /* We used to make the hash table weak so that unreferenced |
846 | compostions can be garbage-collected. But, usually once | |
847 | created compositions are repeatedly used in an Emacs session, | |
848 | and thus it's not worth to save memory in such a way. So, we | |
849 | make the table not weak. */ | |
ca4c9455 | 850 | args[2] = QCweakness; |
1ace9906 | 851 | args[3] = Qnil; |
ca4c9455 KH |
852 | args[4] = QCsize; |
853 | args[5] = make_number (311); | |
09654086 | 854 | composition_hash_table = Fmake_hash_table (6, args); |
ca4c9455 KH |
855 | staticpro (&composition_hash_table); |
856 | } | |
857 | ||
858 | /* Text property `composition' should be nonsticky by default. */ | |
859 | Vtext_property_default_nonsticky | |
860 | = Fcons (Fcons (Qcomposition, Qt), Vtext_property_default_nonsticky); | |
861 | ||
862 | DEFVAR_LISP ("compose-chars-after-function", &Vcompose_chars_after_function, | |
335c5470 PJ |
863 | doc: /* Function to adjust composition of buffer text. |
864 | ||
865 | The function is called with three arguments FROM, TO, and OBJECT. | |
866 | FROM and TO specify the range of text of which composition should be | |
867 | adjusted. OBJECT, if non-nil, is a string that contains the text. | |
868 | ||
869 | This function is called after a text with `composition' property is | |
870 | inserted or deleted to keep `composition' property of buffer text | |
871 | valid. | |
872 | ||
873 | The default value is the function `compose-chars-after'. */); | |
ca4c9455 KH |
874 | Vcompose_chars_after_function = intern ("compose-chars-after"); |
875 | ||
40add26d KH |
876 | Qcomposition_function_table = intern ("composition-function-table"); |
877 | staticpro (&Qcomposition_function_table); | |
878 | ||
879 | /* Intern this now in case it isn't already done. | |
880 | Setting this variable twice is harmless. | |
881 | But don't staticpro it here--that is done in alloc.c. */ | |
882 | Qchar_table_extra_slots = intern ("char-table-extra-slots"); | |
883 | ||
884 | Fput (Qcomposition_function_table, Qchar_table_extra_slots, make_number (0)); | |
885 | ||
886 | DEFVAR_LISP ("composition-function-table", &Vcomposition_function_table, | |
335c5470 PJ |
887 | doc: /* Char table of patterns and functions to make a composition. |
888 | ||
889 | Each element is nil or an alist of PATTERNs vs FUNCs, where PATTERNs | |
890 | are regular expressions and FUNCs are functions. FUNC is responsible | |
891 | for composing text matching the corresponding PATTERN. FUNC is called | |
892 | with three arguments FROM, TO, and PATTERN. See the function | |
893 | `compose-chars-after' for more detail. | |
894 | ||
895 | This table is looked up by the first character of a composition when | |
896 | the composition gets invalid after a change in a buffer. */); | |
40add26d KH |
897 | Vcomposition_function_table |
898 | = Fmake_char_table (Qcomposition_function_table, Qnil); | |
899 | ||
ca4c9455 KH |
900 | defsubr (&Scompose_region_internal); |
901 | defsubr (&Scompose_string_internal); | |
902 | defsubr (&Sfind_composition_internal); | |
903 | } | |
ab5796a9 MB |
904 | |
905 | /* arch-tag: 79cefaf8-ca48-4eed-97e5-d5afb290d272 | |
906 | (do not change this comment) */ |