| 1 | /* Composite sequence support. |
| 2 | Copyright (C) 2001-2014 Free Software Foundation, Inc. |
| 3 | Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 |
| 4 | National Institute of Advanced Industrial Science and Technology (AIST) |
| 5 | Registration Number H14PRO021 |
| 6 | Copyright (C) 2003, 2006 |
| 7 | National Institute of Advanced Industrial Science and Technology (AIST) |
| 8 | Registration Number H13PRO009 |
| 9 | |
| 10 | This file is part of GNU Emacs. |
| 11 | |
| 12 | GNU Emacs is free software: you can redistribute it and/or modify |
| 13 | it under the terms of the GNU General Public License as published by |
| 14 | the Free Software Foundation, either version 3 of the License, or |
| 15 | (at your option) any later version. |
| 16 | |
| 17 | GNU Emacs is distributed in the hope that it will be useful, |
| 18 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | GNU General Public License for more details. |
| 21 | |
| 22 | You should have received a copy of the GNU General Public License |
| 23 | along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */ |
| 24 | |
| 25 | #include <config.h> |
| 26 | |
| 27 | #include "lisp.h" |
| 28 | #include "character.h" |
| 29 | #include "buffer.h" |
| 30 | #include "coding.h" |
| 31 | #include "intervals.h" |
| 32 | #include "window.h" |
| 33 | #include "frame.h" |
| 34 | #include "dispextern.h" |
| 35 | #include "font.h" |
| 36 | #include "termhooks.h" |
| 37 | |
| 38 | |
| 39 | /* Emacs uses special text property `composition' to support character |
| 40 | composition. A sequence of characters that have the same (i.e. eq) |
| 41 | `composition' property value is treated as a single composite |
| 42 | sequence (we call it just `composition' here after). Characters in |
| 43 | a composition are all composed somehow on the screen. |
| 44 | |
| 45 | The property value has this form when the composition is made: |
| 46 | ((LENGTH . COMPONENTS) . MODIFICATION-FUNC) |
| 47 | then turns to this form: |
| 48 | (COMPOSITION-ID . (LENGTH COMPONENTS-VEC . MODIFICATION-FUNC)) |
| 49 | when the composition is registered in composition_hash_table and |
| 50 | composition_table. These rather peculiar structures were designed |
| 51 | to make it easy to distinguish them quickly (we can do that by |
| 52 | checking only the first element) and to extract LENGTH (from the |
| 53 | former form) and COMPOSITION-ID (from the latter form). |
| 54 | |
| 55 | We register a composition when it is displayed, or when the width |
| 56 | is required (for instance, to calculate columns). |
| 57 | |
| 58 | LENGTH -- Length of the composition. This information is used to |
| 59 | check the validity of the composition. |
| 60 | |
| 61 | COMPONENTS -- Character, string, vector, list, or nil. |
| 62 | |
| 63 | If it is nil, characters in the text are composed relatively |
| 64 | according to their metrics in font glyphs. |
| 65 | |
| 66 | If it is a character or a string, the character or characters |
| 67 | in the string are composed relatively. |
| 68 | |
| 69 | If it is a vector or list of integers, the element is a |
| 70 | character or an encoded composition rule. The characters are |
| 71 | composed according to the rules. (2N)th elements are |
| 72 | characters to be composed and (2N+1)th elements are |
| 73 | composition rules to tell how to compose (2N+2)th element with |
| 74 | the previously composed 2N glyphs. |
| 75 | |
| 76 | COMPONENTS-VEC -- Vector of integers. In a relative composition, |
| 77 | the elements are the characters to be composed. In a rule-base |
| 78 | composition, the elements are characters or encoded |
| 79 | composition rules. |
| 80 | |
| 81 | MODIFICATION-FUNC -- If non nil, it is a function to call when the |
| 82 | composition gets invalid after a modification in a buffer. If |
| 83 | it is nil, a function in `composition-function-table' of the |
| 84 | first character in the sequence is called. |
| 85 | |
| 86 | COMPOSITION-ID --Identification number of the composition. It is |
| 87 | used as an index to composition_table for the composition. |
| 88 | |
| 89 | When Emacs has to display a composition or has to know its |
| 90 | displaying width, the function get_composition_id is called. It |
| 91 | returns COMPOSITION-ID so that the caller can access the |
| 92 | information about the composition through composition_table. If a |
| 93 | COMPOSITION-ID has not yet been assigned to the composition, |
| 94 | get_composition_id checks the validity of `composition' property, |
| 95 | and, if valid, assigns a new ID, registers the information in |
| 96 | composition_hash_table and composition_table, and changes the form |
| 97 | of the property value. If the property is invalid, |
| 98 | get_composition_id returns -1 without changing the property value. |
| 99 | |
| 100 | We use two tables to keep the information about composition; |
| 101 | composition_hash_table and composition_table. |
| 102 | |
| 103 | The former is a hash table whose keys are COMPONENTS-VECs and |
| 104 | values are the corresponding COMPOSITION-IDs. This hash table is |
| 105 | weak, but as each key (COMPONENTS-VEC) is also kept as a value of the |
| 106 | `composition' property, it won't be collected as garbage until all |
| 107 | bits of text that have the same COMPONENTS-VEC are deleted. |
| 108 | |
| 109 | The latter is a table of pointers to `struct composition' indexed |
| 110 | by COMPOSITION-ID. This structure keeps the other information (see |
| 111 | composite.h). |
| 112 | |
| 113 | In general, a text property holds information about individual |
| 114 | characters. But, a `composition' property holds information about |
| 115 | a sequence of characters (in this sense, it is like the `intangible' |
| 116 | property). That means that we should not share the property value |
| 117 | in adjacent compositions -- we can't distinguish them if they have the |
| 118 | same property. So, after any changes, we call |
| 119 | `update_compositions' and change a property of one of adjacent |
| 120 | compositions to a copy of it. This function also runs a proper |
| 121 | composition modification function to make a composition that gets |
| 122 | invalid by the change valid again. |
| 123 | |
| 124 | As the value of the `composition' property holds information about a |
| 125 | specific range of text, the value gets invalid if we change the |
| 126 | text in the range. We treat the `composition' property as always |
| 127 | rear-nonsticky (currently by setting default-text-properties to |
| 128 | (rear-nonsticky (composition))) and we never make properties of |
| 129 | adjacent compositions identical. Thus, any such changes make the |
| 130 | range just shorter. So, we can check the validity of the `composition' |
| 131 | property by comparing LENGTH information with the actual length of |
| 132 | the composition. |
| 133 | |
| 134 | */ |
| 135 | |
| 136 | |
| 137 | Lisp_Object Qcomposition; |
| 138 | |
| 139 | /* Table of pointers to the structure `composition' indexed by |
| 140 | COMPOSITION-ID. This structure is for storing information about |
| 141 | each composition except for COMPONENTS-VEC. */ |
| 142 | struct composition **composition_table; |
| 143 | |
| 144 | /* The current size of `composition_table'. */ |
| 145 | static ptrdiff_t composition_table_size; |
| 146 | |
| 147 | /* Number of compositions currently made. */ |
| 148 | ptrdiff_t n_compositions; |
| 149 | |
| 150 | /* Hash table for compositions. The key is COMPONENTS-VEC of |
| 151 | `composition' property. The value is the corresponding |
| 152 | COMPOSITION-ID. */ |
| 153 | Lisp_Object composition_hash_table; |
| 154 | |
| 155 | static Lisp_Object Qauto_composed; |
| 156 | static Lisp_Object Qauto_composition_function; |
| 157 | /* Maximum number of characters to look back for |
| 158 | auto-compositions. */ |
| 159 | #define MAX_AUTO_COMPOSITION_LOOKBACK 3 |
| 160 | |
| 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 | ptrdiff_t |
| 169 | get_composition_id (ptrdiff_t charpos, ptrdiff_t bytepos, ptrdiff_t nchars, |
| 170 | Lisp_Object prop, Lisp_Object string) |
| 171 | { |
| 172 | Lisp_Object id, length, components, key, *key_contents; |
| 173 | ptrdiff_t glyph_len; |
| 174 | struct Lisp_Hash_Table *hash_table = XHASH_TABLE (composition_hash_table); |
| 175 | ptrdiff_t hash_index; |
| 176 | EMACS_UINT hash_code; |
| 177 | enum composition_method method; |
| 178 | struct composition *cmp; |
| 179 | ptrdiff_t i; |
| 180 | int ch; |
| 181 | |
| 182 | /* Maximum length of a string of glyphs. XftGlyphExtents limits |
| 183 | this to INT_MAX, and Emacs limits it further. Divide INT_MAX - 1 |
| 184 | by 2 because x_produce_glyphs computes glyph_len * 2 + 1. Divide |
| 185 | the size by MAX_MULTIBYTE_LENGTH because encode_terminal_code |
| 186 | multiplies glyph_len by MAX_MULTIBYTE_LENGTH. */ |
| 187 | enum { |
| 188 | GLYPH_LEN_MAX = min ((INT_MAX - 1) / 2, |
| 189 | min (PTRDIFF_MAX, SIZE_MAX) / MAX_MULTIBYTE_LENGTH) |
| 190 | }; |
| 191 | |
| 192 | /* PROP should be |
| 193 | Form-A: ((LENGTH . COMPONENTS) . MODIFICATION-FUNC) |
| 194 | or |
| 195 | Form-B: (COMPOSITION-ID . (LENGTH COMPONENTS-VEC . MODIFICATION-FUNC)) |
| 196 | */ |
| 197 | if (nchars == 0 || !CONSP (prop)) |
| 198 | goto invalid_composition; |
| 199 | |
| 200 | id = XCAR (prop); |
| 201 | if (INTEGERP (id)) |
| 202 | { |
| 203 | /* PROP should be Form-B. */ |
| 204 | if (XINT (id) < 0 || XINT (id) >= n_compositions) |
| 205 | goto invalid_composition; |
| 206 | return XINT (id); |
| 207 | } |
| 208 | |
| 209 | /* PROP should be Form-A. |
| 210 | Thus, ID should be (LENGTH . COMPONENTS). */ |
| 211 | if (!CONSP (id)) |
| 212 | goto invalid_composition; |
| 213 | length = XCAR (id); |
| 214 | if (!INTEGERP (length) || XINT (length) != nchars) |
| 215 | goto invalid_composition; |
| 216 | |
| 217 | components = XCDR (id); |
| 218 | |
| 219 | /* Check if the same composition has already been registered or not |
| 220 | by consulting composition_hash_table. The key for this table is |
| 221 | COMPONENTS (converted to a vector COMPONENTS-VEC) or, if it is |
| 222 | nil, vector of characters in the composition range. */ |
| 223 | if (INTEGERP (components)) |
| 224 | key = Fmake_vector (make_number (1), components); |
| 225 | else if (STRINGP (components) || CONSP (components)) |
| 226 | key = Fvconcat (1, &components); |
| 227 | else if (VECTORP (components)) |
| 228 | key = components; |
| 229 | else if (NILP (components)) |
| 230 | { |
| 231 | key = make_uninit_vector (nchars); |
| 232 | if (STRINGP (string)) |
| 233 | for (i = 0; i < nchars; i++) |
| 234 | { |
| 235 | FETCH_STRING_CHAR_ADVANCE (ch, string, charpos, bytepos); |
| 236 | ASET (key, i, make_number (ch)); |
| 237 | } |
| 238 | else |
| 239 | for (i = 0; i < nchars; i++) |
| 240 | { |
| 241 | FETCH_CHAR_ADVANCE (ch, charpos, bytepos); |
| 242 | ASET (key, i, make_number (ch)); |
| 243 | } |
| 244 | } |
| 245 | else |
| 246 | goto invalid_composition; |
| 247 | |
| 248 | hash_index = hash_lookup (hash_table, key, &hash_code); |
| 249 | if (hash_index >= 0) |
| 250 | { |
| 251 | /* We have already registered the same composition. Change PROP |
| 252 | from Form-A above to Form-B while replacing COMPONENTS with |
| 253 | COMPONENTS-VEC stored in the hash table. We can directly |
| 254 | modify the cons cell of PROP because it is not shared. */ |
| 255 | key = HASH_KEY (hash_table, hash_index); |
| 256 | id = HASH_VALUE (hash_table, hash_index); |
| 257 | XSETCAR (prop, id); |
| 258 | XSETCDR (prop, Fcons (make_number (nchars), Fcons (key, XCDR (prop)))); |
| 259 | return XINT (id); |
| 260 | } |
| 261 | |
| 262 | /* This composition is a new one. We must register it. */ |
| 263 | |
| 264 | /* Check if we have sufficient memory to store this information. */ |
| 265 | if (composition_table_size <= n_compositions) |
| 266 | composition_table = xpalloc (composition_table, &composition_table_size, |
| 267 | 1, -1, sizeof *composition_table); |
| 268 | |
| 269 | key_contents = XVECTOR (key)->contents; |
| 270 | |
| 271 | /* Check if the contents of COMPONENTS are valid if COMPONENTS is a |
| 272 | vector or a list. It should be a sequence of: |
| 273 | char1 rule1 char2 rule2 char3 ... ruleN charN+1 */ |
| 274 | |
| 275 | if (VECTORP (components) |
| 276 | && ASIZE (components) >= 2 |
| 277 | && VECTORP (AREF (components, 0))) |
| 278 | { |
| 279 | /* COMPONENTS is a glyph-string. */ |
| 280 | ptrdiff_t len = ASIZE (key); |
| 281 | |
| 282 | for (i = 1; i < len; i++) |
| 283 | if (! VECTORP (AREF (key, i))) |
| 284 | goto invalid_composition; |
| 285 | } |
| 286 | else if (VECTORP (components) || CONSP (components)) |
| 287 | { |
| 288 | ptrdiff_t len = ASIZE (key); |
| 289 | |
| 290 | /* The number of elements should be odd. */ |
| 291 | if ((len % 2) == 0) |
| 292 | goto invalid_composition; |
| 293 | /* All elements should be integers (character or encoded |
| 294 | composition rule). */ |
| 295 | for (i = 0; i < len; i++) |
| 296 | { |
| 297 | if (!INTEGERP (key_contents[i])) |
| 298 | goto invalid_composition; |
| 299 | } |
| 300 | } |
| 301 | |
| 302 | /* Change PROP from Form-A above to Form-B. We can directly modify |
| 303 | the cons cell of PROP because it is not shared. */ |
| 304 | XSETFASTINT (id, n_compositions); |
| 305 | XSETCAR (prop, id); |
| 306 | XSETCDR (prop, Fcons (make_number (nchars), Fcons (key, XCDR (prop)))); |
| 307 | |
| 308 | /* Register the composition in composition_hash_table. */ |
| 309 | hash_index = hash_put (hash_table, key, id, hash_code); |
| 310 | |
| 311 | method = (NILP (components) |
| 312 | ? COMPOSITION_RELATIVE |
| 313 | : ((INTEGERP (components) || STRINGP (components)) |
| 314 | ? COMPOSITION_WITH_ALTCHARS |
| 315 | : COMPOSITION_WITH_RULE_ALTCHARS)); |
| 316 | |
| 317 | glyph_len = (method == COMPOSITION_WITH_RULE_ALTCHARS |
| 318 | ? (ASIZE (key) + 1) / 2 |
| 319 | : ASIZE (key)); |
| 320 | |
| 321 | if (GLYPH_LEN_MAX < glyph_len) |
| 322 | memory_full (SIZE_MAX); |
| 323 | |
| 324 | /* Register the composition in composition_table. */ |
| 325 | cmp = xmalloc (sizeof *cmp); |
| 326 | |
| 327 | cmp->method = method; |
| 328 | cmp->hash_index = hash_index; |
| 329 | cmp->glyph_len = glyph_len; |
| 330 | cmp->offsets = xnmalloc (glyph_len, 2 * sizeof *cmp->offsets); |
| 331 | cmp->font = NULL; |
| 332 | |
| 333 | if (cmp->method != COMPOSITION_WITH_RULE_ALTCHARS) |
| 334 | { |
| 335 | /* Relative composition. */ |
| 336 | cmp->width = 0; |
| 337 | for (i = 0; i < glyph_len; i++) |
| 338 | { |
| 339 | int this_width; |
| 340 | ch = XINT (key_contents[i]); |
| 341 | /* TAB in a composition means display glyphs with padding |
| 342 | space on the left or right. */ |
| 343 | this_width = (ch == '\t' ? 1 : CHAR_WIDTH (ch)); |
| 344 | if (cmp->width < this_width) |
| 345 | cmp->width = this_width; |
| 346 | } |
| 347 | } |
| 348 | else |
| 349 | { |
| 350 | /* Rule-base composition. */ |
| 351 | double leftmost = 0.0, rightmost; |
| 352 | |
| 353 | ch = XINT (key_contents[0]); |
| 354 | rightmost = ch != '\t' ? CHAR_WIDTH (ch) : 1; |
| 355 | |
| 356 | for (i = 1; i < glyph_len; i += 2) |
| 357 | { |
| 358 | int rule, gref, nref; |
| 359 | int this_width; |
| 360 | double this_left; |
| 361 | |
| 362 | rule = XINT (key_contents[i]); |
| 363 | ch = XINT (key_contents[i + 1]); |
| 364 | this_width = ch != '\t' ? CHAR_WIDTH (ch) : 1; |
| 365 | |
| 366 | /* A composition rule is specified by an integer value |
| 367 | that encodes global and new reference points (GREF and |
| 368 | NREF). GREF and NREF are specified by numbers as |
| 369 | below: |
| 370 | 0---1---2 -- ascent |
| 371 | | | |
| 372 | | | |
| 373 | | | |
| 374 | 9--10--11 -- center |
| 375 | | | |
| 376 | ---3---4---5--- baseline |
| 377 | | | |
| 378 | 6---7---8 -- descent |
| 379 | */ |
| 380 | COMPOSITION_DECODE_REFS (rule, gref, nref); |
| 381 | this_left = (leftmost |
| 382 | + (gref % 3) * (rightmost - leftmost) / 2.0 |
| 383 | - (nref % 3) * this_width / 2.0); |
| 384 | |
| 385 | if (this_left < leftmost) |
| 386 | leftmost = this_left; |
| 387 | if (this_left + this_width > rightmost) |
| 388 | rightmost = this_left + this_width; |
| 389 | } |
| 390 | |
| 391 | cmp->width = rightmost - leftmost; |
| 392 | if (cmp->width < (rightmost - leftmost)) |
| 393 | /* To get a ceiling integer value. */ |
| 394 | cmp->width++; |
| 395 | } |
| 396 | |
| 397 | composition_table[n_compositions] = cmp; |
| 398 | |
| 399 | return n_compositions++; |
| 400 | |
| 401 | invalid_composition: |
| 402 | /* Would it be better to remove this `composition' property? */ |
| 403 | return -1; |
| 404 | } |
| 405 | |
| 406 | \f |
| 407 | /* Find a static composition at or nearest to position POS of OBJECT |
| 408 | (buffer or string). |
| 409 | |
| 410 | OBJECT defaults to the current buffer. If there's a composition at |
| 411 | POS, set *START and *END to the start and end of the sequence, |
| 412 | *PROP to the `composition' property, and return 1. |
| 413 | |
| 414 | If there's no composition at POS and LIMIT is negative, return 0. |
| 415 | |
| 416 | Otherwise, search for a composition forward (LIMIT > POS) or |
| 417 | backward (LIMIT < POS). In this case, LIMIT bounds the search. |
| 418 | |
| 419 | If a composition is found, set *START, *END, and *PROP as above, |
| 420 | and return 1, else return 0. |
| 421 | |
| 422 | This doesn't check the validity of composition. */ |
| 423 | |
| 424 | bool |
| 425 | find_composition (ptrdiff_t pos, ptrdiff_t limit, |
| 426 | ptrdiff_t *start, ptrdiff_t *end, |
| 427 | Lisp_Object *prop, Lisp_Object object) |
| 428 | { |
| 429 | Lisp_Object val; |
| 430 | |
| 431 | if (get_property_and_range (pos, Qcomposition, prop, start, end, object)) |
| 432 | return 1; |
| 433 | |
| 434 | if (limit < 0 || limit == pos) |
| 435 | return 0; |
| 436 | |
| 437 | if (limit > pos) /* search forward */ |
| 438 | { |
| 439 | val = Fnext_single_property_change (make_number (pos), Qcomposition, |
| 440 | object, make_number (limit)); |
| 441 | pos = XINT (val); |
| 442 | if (pos == limit) |
| 443 | return 0; |
| 444 | } |
| 445 | else /* search backward */ |
| 446 | { |
| 447 | if (get_property_and_range (pos - 1, Qcomposition, prop, start, end, |
| 448 | object)) |
| 449 | return 1; |
| 450 | val = Fprevious_single_property_change (make_number (pos), Qcomposition, |
| 451 | object, make_number (limit)); |
| 452 | pos = XINT (val); |
| 453 | if (pos == limit) |
| 454 | return 0; |
| 455 | pos--; |
| 456 | } |
| 457 | get_property_and_range (pos, Qcomposition, prop, start, end, object); |
| 458 | return 1; |
| 459 | } |
| 460 | |
| 461 | /* Run a proper function to adjust the composition sitting between |
| 462 | FROM and TO with property PROP. */ |
| 463 | |
| 464 | static void |
| 465 | run_composition_function (ptrdiff_t from, ptrdiff_t to, Lisp_Object prop) |
| 466 | { |
| 467 | Lisp_Object func; |
| 468 | ptrdiff_t start, end; |
| 469 | |
| 470 | func = COMPOSITION_MODIFICATION_FUNC (prop); |
| 471 | /* If an invalid composition precedes or follows, try to make them |
| 472 | valid too. */ |
| 473 | if (from > BEGV |
| 474 | && find_composition (from - 1, -1, &start, &end, &prop, Qnil) |
| 475 | && !composition_valid_p (start, end, prop)) |
| 476 | from = start; |
| 477 | if (to < ZV |
| 478 | && find_composition (to, -1, &start, &end, &prop, Qnil) |
| 479 | && !composition_valid_p (start, end, prop)) |
| 480 | to = end; |
| 481 | if (!NILP (Ffboundp (func))) |
| 482 | call2 (func, make_number (from), make_number (to)); |
| 483 | } |
| 484 | |
| 485 | /* Make invalid compositions adjacent to or inside FROM and TO valid. |
| 486 | CHECK_MASK is bitwise `or' of mask bits defined by macros |
| 487 | CHECK_XXX (see the comment in composite.h). |
| 488 | |
| 489 | It also resets the text-property `auto-composed' to a proper region |
| 490 | so that automatic character composition works correctly later while |
| 491 | displaying the region. |
| 492 | |
| 493 | This function is called when a buffer text is changed. If the |
| 494 | change is deletion, FROM == TO. Otherwise, FROM < TO. */ |
| 495 | |
| 496 | void |
| 497 | update_compositions (ptrdiff_t from, ptrdiff_t to, int check_mask) |
| 498 | { |
| 499 | Lisp_Object prop; |
| 500 | ptrdiff_t start, end; |
| 501 | /* The beginning and end of the region to set the property |
| 502 | `auto-composed' to nil. */ |
| 503 | ptrdiff_t min_pos = from, max_pos = to; |
| 504 | |
| 505 | if (inhibit_modification_hooks) |
| 506 | return; |
| 507 | |
| 508 | /* If FROM and TO are not in a valid range, do nothing. */ |
| 509 | if (! (BEGV <= from && from <= to && to <= ZV)) |
| 510 | return; |
| 511 | |
| 512 | if (check_mask & CHECK_HEAD) |
| 513 | { |
| 514 | /* FROM should be at composition boundary. But, insertion or |
| 515 | deletion will make two compositions adjacent and |
| 516 | indistinguishable when they have same (eq) property. To |
| 517 | avoid it, in such a case, we change the property of the |
| 518 | latter to the copy of it. */ |
| 519 | if (from > BEGV |
| 520 | && find_composition (from - 1, -1, &start, &end, &prop, Qnil) |
| 521 | && composition_valid_p (start, end, prop)) |
| 522 | { |
| 523 | min_pos = start; |
| 524 | if (end > to) |
| 525 | max_pos = end; |
| 526 | if (from < end) |
| 527 | Fput_text_property (make_number (from), make_number (end), |
| 528 | Qcomposition, |
| 529 | Fcons (XCAR (prop), XCDR (prop)), Qnil); |
| 530 | run_composition_function (start, end, prop); |
| 531 | from = end; |
| 532 | } |
| 533 | else if (from < ZV |
| 534 | && find_composition (from, -1, &start, &from, &prop, Qnil) |
| 535 | && composition_valid_p (start, from, prop)) |
| 536 | { |
| 537 | if (from > to) |
| 538 | max_pos = from; |
| 539 | run_composition_function (start, from, prop); |
| 540 | } |
| 541 | } |
| 542 | |
| 543 | if (check_mask & CHECK_INSIDE) |
| 544 | { |
| 545 | /* In this case, we are sure that (check & CHECK_TAIL) is also |
| 546 | nonzero. Thus, here we should check only compositions before |
| 547 | (to - 1). */ |
| 548 | while (from < to - 1 |
| 549 | && find_composition (from, to, &start, &from, &prop, Qnil) |
| 550 | && composition_valid_p (start, from, prop) |
| 551 | && from < to - 1) |
| 552 | run_composition_function (start, from, prop); |
| 553 | } |
| 554 | |
| 555 | if (check_mask & CHECK_TAIL) |
| 556 | { |
| 557 | if (from < to |
| 558 | && find_composition (to - 1, -1, &start, &end, &prop, Qnil) |
| 559 | && composition_valid_p (start, end, prop)) |
| 560 | { |
| 561 | /* TO should be also at composition boundary. But, |
| 562 | insertion or deletion will make two compositions adjacent |
| 563 | and indistinguishable when they have same (eq) property. |
| 564 | To avoid it, in such a case, we change the property of |
| 565 | the former to the copy of it. */ |
| 566 | if (to < end) |
| 567 | { |
| 568 | Fput_text_property (make_number (start), make_number (to), |
| 569 | Qcomposition, |
| 570 | Fcons (XCAR (prop), XCDR (prop)), Qnil); |
| 571 | max_pos = end; |
| 572 | } |
| 573 | run_composition_function (start, end, prop); |
| 574 | } |
| 575 | else if (to < ZV |
| 576 | && find_composition (to, -1, &start, &end, &prop, Qnil) |
| 577 | && composition_valid_p (start, end, prop)) |
| 578 | { |
| 579 | run_composition_function (start, end, prop); |
| 580 | max_pos = end; |
| 581 | } |
| 582 | } |
| 583 | if (min_pos < max_pos) |
| 584 | { |
| 585 | ptrdiff_t count = SPECPDL_INDEX (); |
| 586 | |
| 587 | specbind (Qinhibit_read_only, Qt); |
| 588 | specbind (Qinhibit_modification_hooks, Qt); |
| 589 | specbind (Qinhibit_point_motion_hooks, Qt); |
| 590 | Fremove_list_of_text_properties (make_number (min_pos), |
| 591 | make_number (max_pos), |
| 592 | list1 (Qauto_composed), Qnil); |
| 593 | unbind_to (count, Qnil); |
| 594 | } |
| 595 | } |
| 596 | |
| 597 | |
| 598 | /* Modify composition property values in LIST destructively. LIST is |
| 599 | a list as returned from text_property_list. Change values to the |
| 600 | top-level copies of them so that none of them are `eq'. */ |
| 601 | |
| 602 | void |
| 603 | make_composition_value_copy (Lisp_Object list) |
| 604 | { |
| 605 | Lisp_Object plist, val; |
| 606 | |
| 607 | for (; CONSP (list); list = XCDR (list)) |
| 608 | { |
| 609 | plist = XCAR (XCDR (XCDR (XCAR (list)))); |
| 610 | while (CONSP (plist) && CONSP (XCDR (plist))) |
| 611 | { |
| 612 | if (EQ (XCAR (plist), Qcomposition) |
| 613 | && (val = XCAR (XCDR (plist)), CONSP (val))) |
| 614 | XSETCAR (XCDR (plist), Fcons (XCAR (val), XCDR (val))); |
| 615 | plist = XCDR (XCDR (plist)); |
| 616 | } |
| 617 | } |
| 618 | } |
| 619 | |
| 620 | |
| 621 | /* Make text in the region between START and END a composition that |
| 622 | has COMPONENTS and MODIFICATION-FUNC. |
| 623 | |
| 624 | If STRING is non-nil, then operate on characters contained between |
| 625 | indices START and END in STRING. */ |
| 626 | |
| 627 | void |
| 628 | compose_text (ptrdiff_t start, ptrdiff_t end, Lisp_Object components, |
| 629 | Lisp_Object modification_func, Lisp_Object string) |
| 630 | { |
| 631 | Lisp_Object prop; |
| 632 | |
| 633 | prop = Fcons (Fcons (make_number (end - start), components), |
| 634 | modification_func); |
| 635 | Fput_text_property (make_number (start), make_number (end), |
| 636 | Qcomposition, prop, string); |
| 637 | } |
| 638 | |
| 639 | /* Lisp glyph-string handlers. */ |
| 640 | |
| 641 | /* Hash table for automatic composition. The key is a header of a |
| 642 | lgstring (Lispy glyph-string), and the value is a body of a |
| 643 | lgstring. */ |
| 644 | |
| 645 | static Lisp_Object gstring_hash_table; |
| 646 | |
| 647 | static Lisp_Object gstring_lookup_cache (Lisp_Object); |
| 648 | |
| 649 | static Lisp_Object |
| 650 | gstring_lookup_cache (Lisp_Object header) |
| 651 | { |
| 652 | struct Lisp_Hash_Table *h = XHASH_TABLE (gstring_hash_table); |
| 653 | ptrdiff_t i = hash_lookup (h, header, NULL); |
| 654 | |
| 655 | return (i >= 0 ? HASH_VALUE (h, i) : Qnil); |
| 656 | } |
| 657 | |
| 658 | Lisp_Object |
| 659 | composition_gstring_put_cache (Lisp_Object gstring, ptrdiff_t len) |
| 660 | { |
| 661 | struct Lisp_Hash_Table *h = XHASH_TABLE (gstring_hash_table); |
| 662 | EMACS_UINT hash; |
| 663 | Lisp_Object header, copy; |
| 664 | ptrdiff_t i; |
| 665 | |
| 666 | header = LGSTRING_HEADER (gstring); |
| 667 | hash = h->test.hashfn (&h->test, header); |
| 668 | if (len < 0) |
| 669 | { |
| 670 | ptrdiff_t j, glyph_len = LGSTRING_GLYPH_LEN (gstring); |
| 671 | for (j = 0; j < glyph_len; j++) |
| 672 | if (NILP (LGSTRING_GLYPH (gstring, j))) |
| 673 | break; |
| 674 | len = j; |
| 675 | } |
| 676 | |
| 677 | copy = Fmake_vector (make_number (len + 2), Qnil); |
| 678 | LGSTRING_SET_HEADER (copy, Fcopy_sequence (header)); |
| 679 | for (i = 0; i < len; i++) |
| 680 | LGSTRING_SET_GLYPH (copy, i, Fcopy_sequence (LGSTRING_GLYPH (gstring, i))); |
| 681 | i = hash_put (h, LGSTRING_HEADER (copy), copy, hash); |
| 682 | LGSTRING_SET_ID (copy, make_number (i)); |
| 683 | return copy; |
| 684 | } |
| 685 | |
| 686 | Lisp_Object |
| 687 | composition_gstring_from_id (ptrdiff_t id) |
| 688 | { |
| 689 | struct Lisp_Hash_Table *h = XHASH_TABLE (gstring_hash_table); |
| 690 | |
| 691 | return HASH_VALUE (h, id); |
| 692 | } |
| 693 | |
| 694 | bool |
| 695 | composition_gstring_p (Lisp_Object gstring) |
| 696 | { |
| 697 | Lisp_Object header; |
| 698 | ptrdiff_t i; |
| 699 | |
| 700 | if (! VECTORP (gstring) || ASIZE (gstring) < 2) |
| 701 | return 0; |
| 702 | header = LGSTRING_HEADER (gstring); |
| 703 | if (! VECTORP (header) || ASIZE (header) < 2) |
| 704 | return 0; |
| 705 | if (! NILP (LGSTRING_FONT (gstring)) |
| 706 | && (! FONT_OBJECT_P (LGSTRING_FONT (gstring)) |
| 707 | && ! CODING_SYSTEM_P (LGSTRING_FONT (gstring)))) |
| 708 | return 0; |
| 709 | for (i = 1; i < ASIZE (LGSTRING_HEADER (gstring)); i++) |
| 710 | if (! NATNUMP (AREF (LGSTRING_HEADER (gstring), i))) |
| 711 | return 0; |
| 712 | if (! NILP (LGSTRING_ID (gstring)) && ! NATNUMP (LGSTRING_ID (gstring))) |
| 713 | return 0; |
| 714 | for (i = 0; i < LGSTRING_GLYPH_LEN (gstring); i++) |
| 715 | { |
| 716 | Lisp_Object glyph = LGSTRING_GLYPH (gstring, i); |
| 717 | if (NILP (glyph)) |
| 718 | break; |
| 719 | if (! VECTORP (glyph) || ASIZE (glyph) != LGLYPH_SIZE) |
| 720 | return 0; |
| 721 | } |
| 722 | return 1; |
| 723 | } |
| 724 | |
| 725 | int |
| 726 | composition_gstring_width (Lisp_Object gstring, ptrdiff_t from, ptrdiff_t to, |
| 727 | struct font_metrics *metrics) |
| 728 | { |
| 729 | Lisp_Object *glyph; |
| 730 | int width = 0; |
| 731 | |
| 732 | if (metrics) |
| 733 | { |
| 734 | Lisp_Object font_object = LGSTRING_FONT (gstring); |
| 735 | |
| 736 | if (FONT_OBJECT_P (font_object)) |
| 737 | { |
| 738 | struct font *font = XFONT_OBJECT (font_object); |
| 739 | |
| 740 | metrics->ascent = font->ascent; |
| 741 | metrics->descent = font->descent; |
| 742 | } |
| 743 | else |
| 744 | { |
| 745 | metrics->ascent = 1; |
| 746 | metrics->descent = 0; |
| 747 | } |
| 748 | metrics->width = metrics->lbearing = metrics->rbearing = 0; |
| 749 | } |
| 750 | for (glyph = lgstring_glyph_addr (gstring, from); from < to; from++, glyph++) |
| 751 | { |
| 752 | int x; |
| 753 | |
| 754 | if (NILP (LGLYPH_ADJUSTMENT (*glyph))) |
| 755 | width += LGLYPH_WIDTH (*glyph); |
| 756 | else |
| 757 | width += LGLYPH_WADJUST (*glyph); |
| 758 | if (metrics) |
| 759 | { |
| 760 | x = metrics->width + LGLYPH_LBEARING (*glyph) + LGLYPH_XOFF (*glyph); |
| 761 | if (metrics->lbearing > x) |
| 762 | metrics->lbearing = x; |
| 763 | x = metrics->width + LGLYPH_RBEARING (*glyph) + LGLYPH_XOFF (*glyph); |
| 764 | if (metrics->rbearing < x) |
| 765 | metrics->rbearing = x; |
| 766 | metrics->width = width; |
| 767 | x = LGLYPH_ASCENT (*glyph) - LGLYPH_YOFF (*glyph); |
| 768 | if (metrics->ascent < x) |
| 769 | metrics->ascent = x; |
| 770 | x = LGLYPH_DESCENT (*glyph) + LGLYPH_YOFF (*glyph); |
| 771 | if (metrics->descent < x) |
| 772 | metrics->descent = x; |
| 773 | } |
| 774 | } |
| 775 | return width; |
| 776 | } |
| 777 | |
| 778 | |
| 779 | static Lisp_Object gstring_work; |
| 780 | static Lisp_Object gstring_work_headers; |
| 781 | |
| 782 | static Lisp_Object |
| 783 | fill_gstring_header (Lisp_Object header, ptrdiff_t from, ptrdiff_t from_byte, |
| 784 | ptrdiff_t to, Lisp_Object font_object, Lisp_Object string) |
| 785 | { |
| 786 | ptrdiff_t len = to - from, i; |
| 787 | |
| 788 | if (len == 0) |
| 789 | error ("Attempt to shape zero-length text"); |
| 790 | if (VECTORP (header)) |
| 791 | { |
| 792 | if (ASIZE (header) != len + 1) |
| 793 | args_out_of_range (header, make_number (len + 1)); |
| 794 | } |
| 795 | else |
| 796 | { |
| 797 | if (len <= 8) |
| 798 | header = AREF (gstring_work_headers, len - 1); |
| 799 | else |
| 800 | header = make_uninit_vector (len + 1); |
| 801 | } |
| 802 | |
| 803 | ASET (header, 0, font_object); |
| 804 | for (i = 0; i < len; i++) |
| 805 | { |
| 806 | int c; |
| 807 | |
| 808 | if (NILP (string)) |
| 809 | FETCH_CHAR_ADVANCE_NO_CHECK (c, from, from_byte); |
| 810 | else |
| 811 | FETCH_STRING_CHAR_ADVANCE_NO_CHECK (c, string, from, from_byte); |
| 812 | ASET (header, i + 1, make_number (c)); |
| 813 | } |
| 814 | return header; |
| 815 | } |
| 816 | |
| 817 | static void |
| 818 | fill_gstring_body (Lisp_Object gstring) |
| 819 | { |
| 820 | Lisp_Object font_object = LGSTRING_FONT (gstring); |
| 821 | Lisp_Object header = AREF (gstring, 0); |
| 822 | ptrdiff_t len = LGSTRING_CHAR_LEN (gstring); |
| 823 | ptrdiff_t i; |
| 824 | |
| 825 | for (i = 0; i < len; i++) |
| 826 | { |
| 827 | Lisp_Object g = LGSTRING_GLYPH (gstring, i); |
| 828 | int c = XFASTINT (AREF (header, i + 1)); |
| 829 | |
| 830 | if (NILP (g)) |
| 831 | { |
| 832 | g = LGLYPH_NEW (); |
| 833 | LGSTRING_SET_GLYPH (gstring, i, g); |
| 834 | } |
| 835 | LGLYPH_SET_FROM (g, i); |
| 836 | LGLYPH_SET_TO (g, i); |
| 837 | LGLYPH_SET_CHAR (g, c); |
| 838 | if (FONT_OBJECT_P (font_object)) |
| 839 | { |
| 840 | font_fill_lglyph_metrics (g, font_object); |
| 841 | } |
| 842 | else |
| 843 | { |
| 844 | int width = XFASTINT (CHAR_TABLE_REF (Vchar_width_table, c)); |
| 845 | |
| 846 | LGLYPH_SET_CODE (g, c); |
| 847 | LGLYPH_SET_LBEARING (g, 0); |
| 848 | LGLYPH_SET_RBEARING (g, width); |
| 849 | LGLYPH_SET_WIDTH (g, width); |
| 850 | LGLYPH_SET_ASCENT (g, 1); |
| 851 | LGLYPH_SET_DESCENT (g, 0); |
| 852 | } |
| 853 | LGLYPH_SET_ADJUSTMENT (g, Qnil); |
| 854 | } |
| 855 | if (i < LGSTRING_GLYPH_LEN (gstring)) |
| 856 | LGSTRING_SET_GLYPH (gstring, i, Qnil); |
| 857 | } |
| 858 | |
| 859 | |
| 860 | /* Try to compose the characters at CHARPOS according to composition |
| 861 | rule RULE ([PATTERN PREV-CHARS FUNC]). LIMIT limits the characters |
| 862 | to compose. STRING, if not nil, is a target string. WIN is a |
| 863 | window where the characters are being displayed. If characters are |
| 864 | successfully composed, return the composition as a glyph-string |
| 865 | object. Otherwise return nil. */ |
| 866 | |
| 867 | static Lisp_Object |
| 868 | autocmp_chars (Lisp_Object rule, ptrdiff_t charpos, ptrdiff_t bytepos, |
| 869 | ptrdiff_t limit, struct window *win, struct face *face, |
| 870 | Lisp_Object string) |
| 871 | { |
| 872 | ptrdiff_t count = SPECPDL_INDEX (); |
| 873 | struct frame *f = XFRAME (win->frame); |
| 874 | Lisp_Object pos = make_number (charpos); |
| 875 | ptrdiff_t to; |
| 876 | ptrdiff_t pt = PT, pt_byte = PT_BYTE; |
| 877 | Lisp_Object re, font_object, lgstring; |
| 878 | ptrdiff_t len; |
| 879 | |
| 880 | record_unwind_save_match_data (); |
| 881 | re = AREF (rule, 0); |
| 882 | if (NILP (re)) |
| 883 | len = 1; |
| 884 | else if (! STRINGP (re)) |
| 885 | return unbind_to (count, Qnil); |
| 886 | else if ((len = fast_looking_at (re, charpos, bytepos, limit, -1, string)) |
| 887 | > 0) |
| 888 | { |
| 889 | if (NILP (string)) |
| 890 | len = BYTE_TO_CHAR (bytepos + len) - charpos; |
| 891 | else |
| 892 | len = string_byte_to_char (string, bytepos + len) - charpos; |
| 893 | } |
| 894 | if (len <= 0) |
| 895 | return unbind_to (count, Qnil); |
| 896 | to = limit = charpos + len; |
| 897 | #ifdef HAVE_WINDOW_SYSTEM |
| 898 | if (FRAME_WINDOW_P (f)) |
| 899 | { |
| 900 | font_object = font_range (charpos, bytepos, &to, win, face, string); |
| 901 | if (! FONT_OBJECT_P (font_object) |
| 902 | || (! NILP (re) |
| 903 | && to < limit |
| 904 | && (fast_looking_at (re, charpos, bytepos, to, -1, string) <= 0))) |
| 905 | return unbind_to (count, Qnil); |
| 906 | } |
| 907 | else |
| 908 | #endif /* not HAVE_WINDOW_SYSTEM */ |
| 909 | font_object = win->frame; |
| 910 | lgstring = Fcomposition_get_gstring (pos, make_number (to), font_object, |
| 911 | string); |
| 912 | if (NILP (LGSTRING_ID (lgstring))) |
| 913 | { |
| 914 | /* Save point as marker before calling out to lisp. */ |
| 915 | if (NILP (string)) |
| 916 | record_unwind_protect (restore_point_unwind, |
| 917 | build_marker (current_buffer, pt, pt_byte)); |
| 918 | lgstring = safe_call (6, Vauto_composition_function, AREF (rule, 2), |
| 919 | pos, make_number (to), font_object, string); |
| 920 | } |
| 921 | return unbind_to (count, lgstring); |
| 922 | } |
| 923 | |
| 924 | static Lisp_Object _work_val; |
| 925 | |
| 926 | /* 1 iff the character C is composable. Characters of general |
| 927 | category Z? or C? are not composable except for ZWNJ and ZWJ. */ |
| 928 | |
| 929 | #define CHAR_COMPOSABLE_P(C) \ |
| 930 | ((C) > ' ' \ |
| 931 | && ((C) == 0x200C || (C) == 0x200D \ |
| 932 | || (_work_val = CHAR_TABLE_REF (Vunicode_category_table, (C)), \ |
| 933 | (INTEGERP (_work_val) \ |
| 934 | && (XINT (_work_val) <= UNICODE_CATEGORY_So))))) |
| 935 | |
| 936 | /* Update cmp_it->stop_pos to the next position after CHARPOS (and |
| 937 | BYTEPOS) where character composition may happen. If BYTEPOS is |
| 938 | negative, compute it. ENDPOS is a limit of searching. If it is |
| 939 | less than CHARPOS, search backward to ENDPOS+1 assuming that |
| 940 | set_iterator_to_next works in reverse order. In this case, if a |
| 941 | composition closest to CHARPOS is found, set cmp_it->stop_pos to |
| 942 | the last character of the composition. |
| 943 | |
| 944 | If no composition is found, set cmp_it->ch to -2. If a static |
| 945 | composition is found, set cmp_it->ch to -1. Otherwise, set |
| 946 | cmp_it->ch to the character that triggers the automatic |
| 947 | composition. */ |
| 948 | |
| 949 | void |
| 950 | composition_compute_stop_pos (struct composition_it *cmp_it, ptrdiff_t charpos, ptrdiff_t bytepos, ptrdiff_t endpos, Lisp_Object string) |
| 951 | { |
| 952 | ptrdiff_t start, end; |
| 953 | int c; |
| 954 | Lisp_Object prop, val; |
| 955 | /* This is from forward_to_next_line_start in xdisp.c. */ |
| 956 | const int MAX_NEWLINE_DISTANCE = 500; |
| 957 | |
| 958 | if (charpos < endpos) |
| 959 | { |
| 960 | if (endpos > charpos + MAX_NEWLINE_DISTANCE) |
| 961 | endpos = charpos + MAX_NEWLINE_DISTANCE; |
| 962 | } |
| 963 | else if (endpos < charpos) |
| 964 | { |
| 965 | /* We search backward for a position to check composition. */ |
| 966 | if (endpos < 0) |
| 967 | { |
| 968 | /* But we don't know where to stop the searching. */ |
| 969 | endpos = NILP (string) ? BEGV - 1 : -1; |
| 970 | /* Usually we don't reach ENDPOS because we stop searching |
| 971 | at an uncomposable character (NL, LRE, etc). */ |
| 972 | } |
| 973 | } |
| 974 | cmp_it->id = -1; |
| 975 | cmp_it->ch = -2; |
| 976 | cmp_it->reversed_p = 0; |
| 977 | cmp_it->stop_pos = endpos; |
| 978 | if (charpos == endpos) |
| 979 | return; |
| 980 | /* FIXME: Bidi is not yet handled well in static composition. */ |
| 981 | if (charpos < endpos |
| 982 | && find_composition (charpos, endpos, &start, &end, &prop, string) |
| 983 | && start >= charpos |
| 984 | && composition_valid_p (start, end, prop)) |
| 985 | { |
| 986 | cmp_it->stop_pos = endpos = start; |
| 987 | cmp_it->ch = -1; |
| 988 | } |
| 989 | if (NILP (BVAR (current_buffer, enable_multibyte_characters)) |
| 990 | || NILP (Vauto_composition_mode)) |
| 991 | return; |
| 992 | if (bytepos < 0) |
| 993 | { |
| 994 | if (NILP (string)) |
| 995 | bytepos = CHAR_TO_BYTE (charpos); |
| 996 | else |
| 997 | bytepos = string_char_to_byte (string, charpos); |
| 998 | } |
| 999 | |
| 1000 | start = charpos; |
| 1001 | if (charpos < endpos) |
| 1002 | { |
| 1003 | /* Forward search. */ |
| 1004 | while (charpos < endpos) |
| 1005 | { |
| 1006 | if (STRINGP (string)) |
| 1007 | FETCH_STRING_CHAR_ADVANCE (c, string, charpos, bytepos); |
| 1008 | else |
| 1009 | FETCH_CHAR_ADVANCE (c, charpos, bytepos); |
| 1010 | if (c == '\n') |
| 1011 | { |
| 1012 | cmp_it->ch = -2; |
| 1013 | break; |
| 1014 | } |
| 1015 | val = CHAR_TABLE_REF (Vcomposition_function_table, c); |
| 1016 | if (! NILP (val)) |
| 1017 | { |
| 1018 | Lisp_Object elt; |
| 1019 | int ridx; |
| 1020 | |
| 1021 | for (ridx = 0; CONSP (val); val = XCDR (val), ridx++) |
| 1022 | { |
| 1023 | elt = XCAR (val); |
| 1024 | if (VECTORP (elt) && ASIZE (elt) == 3 |
| 1025 | && NATNUMP (AREF (elt, 1)) |
| 1026 | && charpos - 1 - XFASTINT (AREF (elt, 1)) >= start) |
| 1027 | break; |
| 1028 | } |
| 1029 | if (CONSP (val)) |
| 1030 | { |
| 1031 | cmp_it->rule_idx = ridx; |
| 1032 | cmp_it->lookback = XFASTINT (AREF (elt, 1)); |
| 1033 | cmp_it->stop_pos = charpos - 1 - cmp_it->lookback; |
| 1034 | cmp_it->ch = c; |
| 1035 | return; |
| 1036 | } |
| 1037 | } |
| 1038 | } |
| 1039 | if (charpos == endpos) |
| 1040 | { |
| 1041 | /* We couldn't find a composition point before ENDPOS. But, |
| 1042 | some character after ENDPOS may be composed with |
| 1043 | characters before ENDPOS. So, we should stop at the safe |
| 1044 | point. */ |
| 1045 | charpos = endpos - MAX_AUTO_COMPOSITION_LOOKBACK; |
| 1046 | if (charpos < start) |
| 1047 | charpos = start; |
| 1048 | } |
| 1049 | } |
| 1050 | else if (charpos > endpos) |
| 1051 | { |
| 1052 | /* Search backward for a pattern that may be composed and the |
| 1053 | position of (possibly) the last character of the match is |
| 1054 | closest to (but not after) START. The reason for the last |
| 1055 | character is that set_iterator_to_next works in reverse order, |
| 1056 | and thus we must stop at the last character for composition |
| 1057 | check. */ |
| 1058 | unsigned char *p; |
| 1059 | int len; |
| 1060 | /* Limit byte position used in fast_looking_at. This is the |
| 1061 | byte position of the character after START. */ |
| 1062 | ptrdiff_t limit; |
| 1063 | |
| 1064 | if (NILP (string)) |
| 1065 | p = BYTE_POS_ADDR (bytepos); |
| 1066 | else |
| 1067 | p = SDATA (string) + bytepos; |
| 1068 | c = STRING_CHAR_AND_LENGTH (p, len); |
| 1069 | limit = bytepos + len; |
| 1070 | while (CHAR_COMPOSABLE_P (c)) |
| 1071 | { |
| 1072 | val = CHAR_TABLE_REF (Vcomposition_function_table, c); |
| 1073 | if (! NILP (val)) |
| 1074 | { |
| 1075 | Lisp_Object elt; |
| 1076 | int ridx, blen; |
| 1077 | |
| 1078 | for (ridx = 0; CONSP (val); val = XCDR (val), ridx++) |
| 1079 | { |
| 1080 | elt = XCAR (val); |
| 1081 | if (VECTORP (elt) && ASIZE (elt) == 3 |
| 1082 | && NATNUMP (AREF (elt, 1)) |
| 1083 | && charpos - XFASTINT (AREF (elt, 1)) > endpos) |
| 1084 | { |
| 1085 | ptrdiff_t back = XFASTINT (AREF (elt, 1)); |
| 1086 | ptrdiff_t cpos = charpos - back, bpos; |
| 1087 | |
| 1088 | if (back == 0) |
| 1089 | bpos = bytepos; |
| 1090 | else |
| 1091 | bpos = (NILP (string) ? CHAR_TO_BYTE (cpos) |
| 1092 | : string_char_to_byte (string, cpos)); |
| 1093 | if (STRINGP (AREF (elt, 0))) |
| 1094 | blen = fast_looking_at (AREF (elt, 0), cpos, bpos, |
| 1095 | start + 1, limit, string); |
| 1096 | else |
| 1097 | blen = 1; |
| 1098 | if (blen > 0) |
| 1099 | { |
| 1100 | /* Make CPOS point to the last character of |
| 1101 | match. Note that BLEN is byte-length. */ |
| 1102 | if (blen > 1) |
| 1103 | { |
| 1104 | bpos += blen; |
| 1105 | if (NILP (string)) |
| 1106 | cpos = BYTE_TO_CHAR (bpos) - 1; |
| 1107 | else |
| 1108 | cpos = string_byte_to_char (string, bpos) - 1; |
| 1109 | } |
| 1110 | back = cpos - (charpos - back); |
| 1111 | if (cmp_it->stop_pos < cpos |
| 1112 | || (cmp_it->stop_pos == cpos |
| 1113 | && cmp_it->lookback < back)) |
| 1114 | { |
| 1115 | cmp_it->rule_idx = ridx; |
| 1116 | cmp_it->stop_pos = cpos; |
| 1117 | cmp_it->ch = c; |
| 1118 | cmp_it->lookback = back; |
| 1119 | cmp_it->nchars = back + 1; |
| 1120 | } |
| 1121 | } |
| 1122 | } |
| 1123 | } |
| 1124 | } |
| 1125 | if (charpos - 1 == endpos) |
| 1126 | break; |
| 1127 | if (STRINGP (string)) |
| 1128 | { |
| 1129 | p--, bytepos--; |
| 1130 | while (! CHAR_HEAD_P (*p)) |
| 1131 | p--, bytepos--; |
| 1132 | charpos--; |
| 1133 | } |
| 1134 | else |
| 1135 | { |
| 1136 | DEC_BOTH (charpos, bytepos); |
| 1137 | p = BYTE_POS_ADDR (bytepos); |
| 1138 | } |
| 1139 | c = STRING_CHAR (p); |
| 1140 | } |
| 1141 | if (cmp_it->ch >= 0) |
| 1142 | /* We found a position to check. */ |
| 1143 | return; |
| 1144 | /* Skip all uncomposable characters. */ |
| 1145 | if (NILP (string)) |
| 1146 | { |
| 1147 | while (charpos - 1 > endpos && ! CHAR_COMPOSABLE_P (c)) |
| 1148 | { |
| 1149 | DEC_BOTH (charpos, bytepos); |
| 1150 | c = FETCH_MULTIBYTE_CHAR (bytepos); |
| 1151 | } |
| 1152 | } |
| 1153 | else |
| 1154 | { |
| 1155 | while (charpos - 1 > endpos && ! CHAR_COMPOSABLE_P (c)) |
| 1156 | { |
| 1157 | p--; |
| 1158 | while (! CHAR_HEAD_P (*p)) |
| 1159 | p--; |
| 1160 | charpos--; |
| 1161 | c = STRING_CHAR (p); |
| 1162 | } |
| 1163 | } |
| 1164 | } |
| 1165 | cmp_it->stop_pos = charpos; |
| 1166 | } |
| 1167 | |
| 1168 | /* Check if the character at CHARPOS (and BYTEPOS) is composed |
| 1169 | (possibly with the following characters) on window W. ENDPOS limits |
| 1170 | characters to be composed. FACE, if non-NULL, is a base face of |
| 1171 | the character. If STRING is not nil, it is a string containing the |
| 1172 | character to check, and CHARPOS and BYTEPOS are indices in the |
| 1173 | string. In that case, FACE must not be NULL. |
| 1174 | |
| 1175 | If the character is composed, setup members of CMP_IT (id, nglyphs, |
| 1176 | from, to, reversed_p), and return true. Otherwise, update |
| 1177 | CMP_IT->stop_pos, and return false. */ |
| 1178 | |
| 1179 | bool |
| 1180 | composition_reseat_it (struct composition_it *cmp_it, ptrdiff_t charpos, |
| 1181 | ptrdiff_t bytepos, ptrdiff_t endpos, struct window *w, |
| 1182 | struct face *face, Lisp_Object string) |
| 1183 | { |
| 1184 | if (cmp_it->ch == -2) |
| 1185 | { |
| 1186 | composition_compute_stop_pos (cmp_it, charpos, bytepos, endpos, string); |
| 1187 | if (cmp_it->ch == -2 || cmp_it->stop_pos != charpos) |
| 1188 | /* The current position is not composed. */ |
| 1189 | return 0; |
| 1190 | } |
| 1191 | |
| 1192 | if (endpos < 0) |
| 1193 | endpos = NILP (string) ? BEGV : 0; |
| 1194 | |
| 1195 | if (cmp_it->ch < 0) |
| 1196 | { |
| 1197 | /* We are looking at a static composition. */ |
| 1198 | ptrdiff_t start, end; |
| 1199 | Lisp_Object prop; |
| 1200 | |
| 1201 | find_composition (charpos, -1, &start, &end, &prop, string); |
| 1202 | cmp_it->id = get_composition_id (charpos, bytepos, end - start, |
| 1203 | prop, string); |
| 1204 | if (cmp_it->id < 0) |
| 1205 | goto no_composition; |
| 1206 | cmp_it->nchars = end - start; |
| 1207 | cmp_it->nglyphs = composition_table[cmp_it->id]->glyph_len; |
| 1208 | } |
| 1209 | else if (w) |
| 1210 | { |
| 1211 | Lisp_Object lgstring = Qnil; |
| 1212 | Lisp_Object val, elt; |
| 1213 | ptrdiff_t i; |
| 1214 | |
| 1215 | val = CHAR_TABLE_REF (Vcomposition_function_table, cmp_it->ch); |
| 1216 | for (i = 0; i < cmp_it->rule_idx; i++, val = XCDR (val)); |
| 1217 | if (charpos < endpos) |
| 1218 | { |
| 1219 | for (; CONSP (val); val = XCDR (val)) |
| 1220 | { |
| 1221 | elt = XCAR (val); |
| 1222 | if (! VECTORP (elt) || ASIZE (elt) != 3 |
| 1223 | || ! INTEGERP (AREF (elt, 1))) |
| 1224 | continue; |
| 1225 | if (XFASTINT (AREF (elt, 1)) != cmp_it->lookback) |
| 1226 | goto no_composition; |
| 1227 | lgstring = autocmp_chars (elt, charpos, bytepos, endpos, |
| 1228 | w, face, string); |
| 1229 | if (composition_gstring_p (lgstring)) |
| 1230 | break; |
| 1231 | lgstring = Qnil; |
| 1232 | /* Composition failed perhaps because the font doesn't |
| 1233 | support sufficient range of characters. Try the |
| 1234 | other composition rules if any. */ |
| 1235 | } |
| 1236 | cmp_it->reversed_p = 0; |
| 1237 | } |
| 1238 | else |
| 1239 | { |
| 1240 | ptrdiff_t cpos = charpos, bpos = bytepos; |
| 1241 | |
| 1242 | cmp_it->reversed_p = 1; |
| 1243 | elt = XCAR (val); |
| 1244 | if (cmp_it->lookback > 0) |
| 1245 | { |
| 1246 | cpos = charpos - cmp_it->lookback; |
| 1247 | if (STRINGP (string)) |
| 1248 | bpos = string_char_to_byte (string, cpos); |
| 1249 | else |
| 1250 | bpos = CHAR_TO_BYTE (cpos); |
| 1251 | } |
| 1252 | lgstring = autocmp_chars (elt, cpos, bpos, charpos + 1, w, face, |
| 1253 | string); |
| 1254 | if (! composition_gstring_p (lgstring) |
| 1255 | || cpos + LGSTRING_CHAR_LEN (lgstring) - 1 != charpos) |
| 1256 | /* Composition failed or didn't cover the current |
| 1257 | character. */ |
| 1258 | goto no_composition; |
| 1259 | } |
| 1260 | if (NILP (lgstring)) |
| 1261 | goto no_composition; |
| 1262 | if (NILP (LGSTRING_ID (lgstring))) |
| 1263 | lgstring = composition_gstring_put_cache (lgstring, -1); |
| 1264 | cmp_it->id = XINT (LGSTRING_ID (lgstring)); |
| 1265 | for (i = 0; i < LGSTRING_GLYPH_LEN (lgstring); i++) |
| 1266 | if (NILP (LGSTRING_GLYPH (lgstring, i))) |
| 1267 | break; |
| 1268 | cmp_it->nglyphs = i; |
| 1269 | cmp_it->from = 0; |
| 1270 | cmp_it->to = i; |
| 1271 | } |
| 1272 | else |
| 1273 | goto no_composition; |
| 1274 | return 1; |
| 1275 | |
| 1276 | no_composition: |
| 1277 | if (charpos == endpos) |
| 1278 | return 0; |
| 1279 | if (charpos < endpos) |
| 1280 | { |
| 1281 | charpos++; |
| 1282 | if (NILP (string)) |
| 1283 | INC_POS (bytepos); |
| 1284 | else |
| 1285 | bytepos += BYTES_BY_CHAR_HEAD (*(SDATA (string) + bytepos)); |
| 1286 | } |
| 1287 | else |
| 1288 | { |
| 1289 | charpos--; |
| 1290 | /* BYTEPOS is calculated in composition_compute_stop_pos */ |
| 1291 | bytepos = -1; |
| 1292 | } |
| 1293 | if (cmp_it->reversed_p) |
| 1294 | endpos = -1; |
| 1295 | composition_compute_stop_pos (cmp_it, charpos, bytepos, endpos, string); |
| 1296 | return 0; |
| 1297 | } |
| 1298 | |
| 1299 | /* Update charpos, nchars, nbytes, and width of the current grapheme |
| 1300 | cluster. |
| 1301 | |
| 1302 | If the composition is static or automatic in L2R context, the |
| 1303 | cluster is identified by CMP_IT->from, and CHARPOS is the position |
| 1304 | of the first character of the cluster. In this case, update |
| 1305 | CMP_IT->to too. |
| 1306 | |
| 1307 | If the composition is automatic in R2L context, the cluster is |
| 1308 | identified by CMP_IT->to, and CHARPOS is the position of the last |
| 1309 | character of the cluster. In this case, update CMP_IT->from too. |
| 1310 | |
| 1311 | The return value is the character code of the first character of |
| 1312 | the cluster, or -1 if the composition is somehow broken. */ |
| 1313 | |
| 1314 | int |
| 1315 | composition_update_it (struct composition_it *cmp_it, ptrdiff_t charpos, ptrdiff_t bytepos, Lisp_Object string) |
| 1316 | { |
| 1317 | int i, c IF_LINT (= 0); |
| 1318 | |
| 1319 | if (cmp_it->ch < 0) |
| 1320 | { |
| 1321 | /* static composition */ |
| 1322 | struct composition *cmp = composition_table[cmp_it->id]; |
| 1323 | |
| 1324 | cmp_it->charpos = charpos; |
| 1325 | cmp_it->to = cmp_it->nglyphs; |
| 1326 | if (cmp_it->nglyphs == 0) |
| 1327 | c = -1; |
| 1328 | else |
| 1329 | { |
| 1330 | for (i = 0; i < cmp->glyph_len; i++) |
| 1331 | /* TAB in a composition means display glyphs with padding |
| 1332 | space on the left or right. */ |
| 1333 | if ((c = COMPOSITION_GLYPH (cmp, i)) != '\t') |
| 1334 | break; |
| 1335 | if (c == '\t') |
| 1336 | c = ' '; |
| 1337 | } |
| 1338 | cmp_it->width = cmp->width; |
| 1339 | charpos += cmp_it->nchars; |
| 1340 | if (STRINGP (string)) |
| 1341 | cmp_it->nbytes = string_char_to_byte (string, charpos) - bytepos; |
| 1342 | else |
| 1343 | cmp_it->nbytes = CHAR_TO_BYTE (charpos) - bytepos; |
| 1344 | } |
| 1345 | else |
| 1346 | { |
| 1347 | /* Automatic composition. */ |
| 1348 | Lisp_Object gstring = composition_gstring_from_id (cmp_it->id); |
| 1349 | Lisp_Object glyph; |
| 1350 | ptrdiff_t from; |
| 1351 | |
| 1352 | if (cmp_it->nglyphs == 0) |
| 1353 | { |
| 1354 | cmp_it->nchars = LGSTRING_CHAR_LEN (gstring); |
| 1355 | cmp_it->width = 0; |
| 1356 | cmp_it->from = cmp_it->to = 0; |
| 1357 | return -1; |
| 1358 | } |
| 1359 | if (! cmp_it->reversed_p) |
| 1360 | { |
| 1361 | glyph = LGSTRING_GLYPH (gstring, cmp_it->from); |
| 1362 | from = LGLYPH_FROM (glyph); |
| 1363 | for (cmp_it->to = cmp_it->from + 1; cmp_it->to < cmp_it->nglyphs; |
| 1364 | cmp_it->to++) |
| 1365 | { |
| 1366 | glyph = LGSTRING_GLYPH (gstring, cmp_it->to); |
| 1367 | if (LGLYPH_FROM (glyph) != from) |
| 1368 | break; |
| 1369 | } |
| 1370 | cmp_it->charpos = charpos; |
| 1371 | } |
| 1372 | else |
| 1373 | { |
| 1374 | glyph = LGSTRING_GLYPH (gstring, cmp_it->to - 1); |
| 1375 | from = LGLYPH_FROM (glyph); |
| 1376 | cmp_it->charpos = charpos - (LGLYPH_TO (glyph) - from); |
| 1377 | for (cmp_it->from = cmp_it->to - 1; cmp_it->from > 0; |
| 1378 | cmp_it->from--) |
| 1379 | { |
| 1380 | glyph = LGSTRING_GLYPH (gstring, cmp_it->from - 1); |
| 1381 | if (LGLYPH_FROM (glyph) != from) |
| 1382 | break; |
| 1383 | } |
| 1384 | } |
| 1385 | glyph = LGSTRING_GLYPH (gstring, cmp_it->from); |
| 1386 | cmp_it->nchars = LGLYPH_TO (glyph) + 1 - from; |
| 1387 | cmp_it->nbytes = 0; |
| 1388 | cmp_it->width = 0; |
| 1389 | for (i = cmp_it->nchars - 1; i >= 0; i--) |
| 1390 | { |
| 1391 | c = XINT (LGSTRING_CHAR (gstring, from + i)); |
| 1392 | cmp_it->nbytes += CHAR_BYTES (c); |
| 1393 | cmp_it->width += CHAR_WIDTH (c); |
| 1394 | } |
| 1395 | } |
| 1396 | return c; |
| 1397 | } |
| 1398 | |
| 1399 | |
| 1400 | struct position_record |
| 1401 | { |
| 1402 | ptrdiff_t pos, pos_byte; |
| 1403 | unsigned char *p; |
| 1404 | }; |
| 1405 | |
| 1406 | /* Update the members of POSITION to the next character boundary. */ |
| 1407 | #define FORWARD_CHAR(POSITION, STOP) \ |
| 1408 | do { \ |
| 1409 | (POSITION).pos++; \ |
| 1410 | if ((POSITION).pos == (STOP)) \ |
| 1411 | { \ |
| 1412 | (POSITION).p = GAP_END_ADDR; \ |
| 1413 | (POSITION).pos_byte = GPT_BYTE; \ |
| 1414 | } \ |
| 1415 | else \ |
| 1416 | { \ |
| 1417 | (POSITION).pos_byte += BYTES_BY_CHAR_HEAD (*((POSITION).p)); \ |
| 1418 | (POSITION).p += BYTES_BY_CHAR_HEAD (*((POSITION).p)); \ |
| 1419 | } \ |
| 1420 | } while (0) |
| 1421 | |
| 1422 | /* Update the members of POSITION to the previous character boundary. */ |
| 1423 | #define BACKWARD_CHAR(POSITION, STOP) \ |
| 1424 | do { \ |
| 1425 | if ((POSITION).pos == (STOP)) \ |
| 1426 | (POSITION).p = GPT_ADDR; \ |
| 1427 | do { \ |
| 1428 | (POSITION).pos_byte--; \ |
| 1429 | (POSITION).p--; \ |
| 1430 | } while (! CHAR_HEAD_P (*((POSITION).p))); \ |
| 1431 | (POSITION).pos--; \ |
| 1432 | } while (0) |
| 1433 | |
| 1434 | /* This is like find_composition, but find an automatic composition |
| 1435 | instead. It is assured that POS is not within a static |
| 1436 | composition. If found, set *GSTRING to the glyph-string |
| 1437 | representing the composition, and return true. Otherwise, *GSTRING to |
| 1438 | Qnil, and return false. */ |
| 1439 | |
| 1440 | static bool |
| 1441 | find_automatic_composition (ptrdiff_t pos, ptrdiff_t limit, |
| 1442 | ptrdiff_t *start, ptrdiff_t *end, |
| 1443 | Lisp_Object *gstring, Lisp_Object string) |
| 1444 | { |
| 1445 | ptrdiff_t head, tail, stop; |
| 1446 | /* Forward limit position of checking a composition taking a |
| 1447 | looking-back count into account. */ |
| 1448 | ptrdiff_t fore_check_limit; |
| 1449 | struct position_record cur, prev; |
| 1450 | int c; |
| 1451 | Lisp_Object window; |
| 1452 | struct window *w; |
| 1453 | bool need_adjustment = 0; |
| 1454 | |
| 1455 | window = Fget_buffer_window (Fcurrent_buffer (), Qnil); |
| 1456 | if (NILP (window)) |
| 1457 | return 0; |
| 1458 | w = XWINDOW (window); |
| 1459 | |
| 1460 | cur.pos = pos; |
| 1461 | if (NILP (string)) |
| 1462 | { |
| 1463 | head = BEGV, tail = ZV, stop = GPT; |
| 1464 | cur.pos_byte = CHAR_TO_BYTE (cur.pos); |
| 1465 | cur.p = BYTE_POS_ADDR (cur.pos_byte); |
| 1466 | } |
| 1467 | else |
| 1468 | { |
| 1469 | head = 0, tail = SCHARS (string), stop = -1; |
| 1470 | cur.pos_byte = string_char_to_byte (string, cur.pos); |
| 1471 | cur.p = SDATA (string) + cur.pos_byte; |
| 1472 | } |
| 1473 | if (limit < 0) |
| 1474 | /* Finding a composition covering the character after POS is the |
| 1475 | same as setting LIMIT to POS. */ |
| 1476 | limit = pos; |
| 1477 | if (limit <= pos) |
| 1478 | fore_check_limit = min (tail, pos + 1 + MAX_AUTO_COMPOSITION_LOOKBACK); |
| 1479 | else |
| 1480 | fore_check_limit = min (tail, limit + MAX_AUTO_COMPOSITION_LOOKBACK); |
| 1481 | |
| 1482 | /* Provided that we have these possible compositions now: |
| 1483 | |
| 1484 | POS: 1 2 3 4 5 6 7 8 9 |
| 1485 | |-A-| |
| 1486 | |-B-|-C-|--D--| |
| 1487 | |
| 1488 | Here, it is known that characters after positions 1 and 9 can |
| 1489 | never be composed (i.e. ! CHAR_COMPOSABLE_P (CH)), and |
| 1490 | composition A is an invalid one because it's partially covered by |
| 1491 | the valid composition C. And to know whether a composition is |
| 1492 | valid or not, the only way is to start searching forward from a |
| 1493 | position that can not be a tail part of composition (it's 2 in |
| 1494 | the above case). |
| 1495 | |
| 1496 | Now we have these cases (1 through 4): |
| 1497 | |
| 1498 | -- character after POS is ... -- |
| 1499 | not composable composable |
| 1500 | LIMIT <= POS (1) (3) |
| 1501 | POS < LIMIT (2) (4) |
| 1502 | |
| 1503 | Among them, in case (2), we simply search forward from POS. |
| 1504 | |
| 1505 | In the other cases, we at first rewind back to the position where |
| 1506 | the previous character is not composable or the beginning of |
| 1507 | buffer (string), then search compositions forward. In case (1) |
| 1508 | and (3) we repeat this process until a composition is found. */ |
| 1509 | |
| 1510 | while (1) |
| 1511 | { |
| 1512 | c = STRING_CHAR (cur.p); |
| 1513 | if (! CHAR_COMPOSABLE_P (c)) |
| 1514 | { |
| 1515 | if (limit <= pos) /* case (1) */ |
| 1516 | { |
| 1517 | do { |
| 1518 | if (cur.pos <= limit) |
| 1519 | return 0; |
| 1520 | BACKWARD_CHAR (cur, stop); |
| 1521 | c = STRING_CHAR (cur.p); |
| 1522 | } while (! CHAR_COMPOSABLE_P (c)); |
| 1523 | fore_check_limit = cur.pos + 1; |
| 1524 | } |
| 1525 | else /* case (2) */ |
| 1526 | /* No need of rewinding back. */ |
| 1527 | goto search_forward; |
| 1528 | } |
| 1529 | |
| 1530 | /* Rewind back to the position where we can safely search |
| 1531 | forward for compositions. It is assured that the character |
| 1532 | at cur.pos is composable. */ |
| 1533 | while (head < cur.pos) |
| 1534 | { |
| 1535 | prev = cur; |
| 1536 | BACKWARD_CHAR (cur, stop); |
| 1537 | c = STRING_CHAR (cur.p); |
| 1538 | if (! CHAR_COMPOSABLE_P (c)) |
| 1539 | { |
| 1540 | cur = prev; |
| 1541 | break; |
| 1542 | } |
| 1543 | } |
| 1544 | |
| 1545 | search_forward: |
| 1546 | /* Now search forward. */ |
| 1547 | *gstring = Qnil; |
| 1548 | prev = cur; /* remember the start of searching position. */ |
| 1549 | while (cur.pos < fore_check_limit) |
| 1550 | { |
| 1551 | Lisp_Object val; |
| 1552 | |
| 1553 | c = STRING_CHAR (cur.p); |
| 1554 | for (val = CHAR_TABLE_REF (Vcomposition_function_table, c); |
| 1555 | CONSP (val); val = XCDR (val)) |
| 1556 | { |
| 1557 | Lisp_Object elt = XCAR (val); |
| 1558 | |
| 1559 | if (VECTORP (elt) && ASIZE (elt) == 3 && NATNUMP (AREF (elt, 1))) |
| 1560 | { |
| 1561 | EMACS_INT check_pos = cur.pos - XFASTINT (AREF (elt, 1)); |
| 1562 | struct position_record check; |
| 1563 | |
| 1564 | if (check_pos < head |
| 1565 | || (limit <= pos ? pos < check_pos |
| 1566 | : limit <= check_pos)) |
| 1567 | continue; |
| 1568 | for (check = cur; check_pos < check.pos; ) |
| 1569 | BACKWARD_CHAR (check, stop); |
| 1570 | *gstring = autocmp_chars (elt, check.pos, check.pos_byte, |
| 1571 | tail, w, NULL, string); |
| 1572 | need_adjustment = 1; |
| 1573 | if (NILP (*gstring)) |
| 1574 | { |
| 1575 | /* As we have called Lisp, there's a possibility |
| 1576 | that buffer/string is relocated. */ |
| 1577 | if (NILP (string)) |
| 1578 | cur.p = BYTE_POS_ADDR (cur.pos_byte); |
| 1579 | else |
| 1580 | cur.p = SDATA (string) + cur.pos_byte; |
| 1581 | } |
| 1582 | else |
| 1583 | { |
| 1584 | /* We found a candidate of a target composition. */ |
| 1585 | *start = check.pos; |
| 1586 | *end = check.pos + LGSTRING_CHAR_LEN (*gstring); |
| 1587 | if (pos < limit |
| 1588 | ? pos < *end |
| 1589 | : *start <= pos && pos < *end) |
| 1590 | /* This is the target composition. */ |
| 1591 | return 1; |
| 1592 | cur.pos = *end; |
| 1593 | if (NILP (string)) |
| 1594 | { |
| 1595 | cur.pos_byte = CHAR_TO_BYTE (cur.pos); |
| 1596 | cur.p = BYTE_POS_ADDR (cur.pos_byte); |
| 1597 | } |
| 1598 | else |
| 1599 | { |
| 1600 | cur.pos_byte = string_char_to_byte (string, cur.pos); |
| 1601 | cur.p = SDATA (string) + cur.pos_byte; |
| 1602 | } |
| 1603 | break; |
| 1604 | } |
| 1605 | } |
| 1606 | } |
| 1607 | if (! CONSP (val)) |
| 1608 | /* We found no composition here. */ |
| 1609 | FORWARD_CHAR (cur, stop); |
| 1610 | } |
| 1611 | |
| 1612 | if (pos < limit) /* case (2) and (4)*/ |
| 1613 | return 0; |
| 1614 | if (! NILP (*gstring)) |
| 1615 | return 1; |
| 1616 | if (prev.pos == head) |
| 1617 | return 0; |
| 1618 | cur = prev; |
| 1619 | if (need_adjustment) |
| 1620 | { |
| 1621 | if (NILP (string)) |
| 1622 | cur.p = BYTE_POS_ADDR (cur.pos_byte); |
| 1623 | else |
| 1624 | cur.p = SDATA (string) + cur.pos_byte; |
| 1625 | } |
| 1626 | BACKWARD_CHAR (cur, stop); |
| 1627 | } |
| 1628 | } |
| 1629 | |
| 1630 | /* Return the adjusted point provided that point is moved from LAST_PT |
| 1631 | to NEW_PT. */ |
| 1632 | |
| 1633 | ptrdiff_t |
| 1634 | composition_adjust_point (ptrdiff_t last_pt, ptrdiff_t new_pt) |
| 1635 | { |
| 1636 | ptrdiff_t i, beg, end; |
| 1637 | Lisp_Object val; |
| 1638 | |
| 1639 | if (new_pt == BEGV || new_pt == ZV) |
| 1640 | return new_pt; |
| 1641 | |
| 1642 | /* At first check the static composition. */ |
| 1643 | if (get_property_and_range (new_pt, Qcomposition, &val, &beg, &end, Qnil) |
| 1644 | && composition_valid_p (beg, end, val)) |
| 1645 | { |
| 1646 | if (beg < new_pt /* && end > new_pt <- It's always the case. */ |
| 1647 | && (last_pt <= beg || last_pt >= end)) |
| 1648 | return (new_pt < last_pt ? beg : end); |
| 1649 | return new_pt; |
| 1650 | } |
| 1651 | |
| 1652 | if (NILP (BVAR (current_buffer, enable_multibyte_characters)) |
| 1653 | || NILP (Vauto_composition_mode)) |
| 1654 | return new_pt; |
| 1655 | |
| 1656 | /* Next check the automatic composition. */ |
| 1657 | if (! find_automatic_composition (new_pt, (ptrdiff_t) -1, &beg, &end, &val, |
| 1658 | Qnil) |
| 1659 | || beg == new_pt) |
| 1660 | return new_pt; |
| 1661 | for (i = 0; i < LGSTRING_GLYPH_LEN (val); i++) |
| 1662 | { |
| 1663 | Lisp_Object glyph = LGSTRING_GLYPH (val, i); |
| 1664 | |
| 1665 | if (NILP (glyph)) |
| 1666 | break; |
| 1667 | if (beg + LGLYPH_FROM (glyph) == new_pt) |
| 1668 | return new_pt; |
| 1669 | if (beg + LGLYPH_TO (glyph) >= new_pt) |
| 1670 | return (new_pt < last_pt |
| 1671 | ? beg + LGLYPH_FROM (glyph) |
| 1672 | : beg + LGLYPH_TO (glyph) + 1); |
| 1673 | } |
| 1674 | return new_pt; |
| 1675 | } |
| 1676 | |
| 1677 | DEFUN ("composition-get-gstring", Fcomposition_get_gstring, |
| 1678 | Scomposition_get_gstring, 4, 4, 0, |
| 1679 | doc: /* Return a glyph-string for characters between FROM and TO. |
| 1680 | If the glyph string is for graphic display, FONT-OBJECT must be |
| 1681 | a font-object to use for those characters. |
| 1682 | Otherwise (for terminal display), FONT-OBJECT must be a terminal ID, a |
| 1683 | frame, or nil for the selected frame's terminal device. |
| 1684 | |
| 1685 | If the optional 4th argument STRING is not nil, it is a string |
| 1686 | containing the target characters between indices FROM and TO. |
| 1687 | Otherwise FROM and TO are character positions in current buffer; |
| 1688 | they can be in either order, and can be integers or markers. |
| 1689 | |
| 1690 | A glyph-string is a vector containing information about how to display |
| 1691 | a specific character sequence. The format is: |
| 1692 | [HEADER ID GLYPH ...] |
| 1693 | |
| 1694 | HEADER is a vector of this form: |
| 1695 | [FONT-OBJECT CHAR ...] |
| 1696 | where |
| 1697 | FONT-OBJECT is a font-object for all glyphs in the glyph-string, |
| 1698 | or the terminal coding system of the specified terminal. |
| 1699 | CHARs are characters to be composed by GLYPHs. |
| 1700 | |
| 1701 | ID is an identification number of the glyph-string. It may be nil if |
| 1702 | not yet shaped. |
| 1703 | |
| 1704 | GLYPH is a vector whose elements have this form: |
| 1705 | [ FROM-IDX TO-IDX C CODE WIDTH LBEARING RBEARING ASCENT DESCENT |
| 1706 | [ [X-OFF Y-OFF WADJUST] | nil] ] |
| 1707 | where |
| 1708 | FROM-IDX and TO-IDX are used internally and should not be touched. |
| 1709 | C is the character of the glyph. |
| 1710 | CODE is the glyph-code of C in FONT-OBJECT. |
| 1711 | WIDTH thru DESCENT are the metrics (in pixels) of the glyph. |
| 1712 | X-OFF and Y-OFF are offsets to the base position for the glyph. |
| 1713 | WADJUST is the adjustment to the normal width of the glyph. |
| 1714 | |
| 1715 | If GLYPH is nil, the remaining elements of the glyph-string vector |
| 1716 | should be ignored. */) |
| 1717 | (Lisp_Object from, Lisp_Object to, Lisp_Object font_object, Lisp_Object string) |
| 1718 | { |
| 1719 | Lisp_Object gstring, header; |
| 1720 | ptrdiff_t frompos, frombyte, topos; |
| 1721 | |
| 1722 | if (! FONT_OBJECT_P (font_object)) |
| 1723 | { |
| 1724 | struct coding_system *coding; |
| 1725 | struct terminal *terminal = get_terminal (font_object, 1); |
| 1726 | |
| 1727 | coding = ((TERMINAL_TERMINAL_CODING (terminal)->common_flags |
| 1728 | & CODING_REQUIRE_ENCODING_MASK) |
| 1729 | ? TERMINAL_TERMINAL_CODING (terminal) : &safe_terminal_coding); |
| 1730 | font_object = CODING_ID_NAME (coding->id); |
| 1731 | } |
| 1732 | |
| 1733 | if (NILP (string)) |
| 1734 | { |
| 1735 | if (NILP (BVAR (current_buffer, enable_multibyte_characters))) |
| 1736 | error ("Attempt to shape unibyte text"); |
| 1737 | validate_region (&from, &to); |
| 1738 | frompos = XFASTINT (from); |
| 1739 | topos = XFASTINT (to); |
| 1740 | frombyte = CHAR_TO_BYTE (frompos); |
| 1741 | } |
| 1742 | else |
| 1743 | { |
| 1744 | CHECK_NATNUM (from); |
| 1745 | CHECK_NATNUM (to); |
| 1746 | CHECK_STRING (string); |
| 1747 | if (! STRING_MULTIBYTE (string)) |
| 1748 | error ("Attempt to shape unibyte text"); |
| 1749 | if (! (XINT (from) <= XINT (to) && XINT (to) <= SCHARS (string))) |
| 1750 | args_out_of_range_3 (string, from, to); |
| 1751 | frompos = XFASTINT (from); |
| 1752 | topos = XFASTINT (to); |
| 1753 | frombyte = string_char_to_byte (string, frompos); |
| 1754 | } |
| 1755 | |
| 1756 | header = fill_gstring_header (Qnil, frompos, frombyte, |
| 1757 | topos, font_object, string); |
| 1758 | gstring = gstring_lookup_cache (header); |
| 1759 | if (! NILP (gstring)) |
| 1760 | return gstring; |
| 1761 | |
| 1762 | if (LGSTRING_GLYPH_LEN (gstring_work) < topos - frompos) |
| 1763 | gstring_work = Fmake_vector (make_number (topos - frompos + 2), Qnil); |
| 1764 | LGSTRING_SET_HEADER (gstring_work, header); |
| 1765 | LGSTRING_SET_ID (gstring_work, Qnil); |
| 1766 | fill_gstring_body (gstring_work); |
| 1767 | return gstring_work; |
| 1768 | } |
| 1769 | |
| 1770 | \f |
| 1771 | /* Emacs Lisp APIs. */ |
| 1772 | |
| 1773 | DEFUN ("compose-region-internal", Fcompose_region_internal, |
| 1774 | Scompose_region_internal, 2, 4, 0, |
| 1775 | doc: /* Internal use only. |
| 1776 | |
| 1777 | Compose text in the region between START and END. |
| 1778 | Optional 3rd and 4th arguments are COMPONENTS and MODIFICATION-FUNC |
| 1779 | for the composition. See `compose-region' for more details. */) |
| 1780 | (Lisp_Object start, Lisp_Object end, Lisp_Object components, Lisp_Object modification_func) |
| 1781 | { |
| 1782 | validate_region (&start, &end); |
| 1783 | if (!NILP (components) |
| 1784 | && !INTEGERP (components) |
| 1785 | && !CONSP (components) |
| 1786 | && !STRINGP (components)) |
| 1787 | CHECK_VECTOR (components); |
| 1788 | |
| 1789 | compose_text (XINT (start), XINT (end), components, modification_func, Qnil); |
| 1790 | return Qnil; |
| 1791 | } |
| 1792 | |
| 1793 | DEFUN ("compose-string-internal", Fcompose_string_internal, |
| 1794 | Scompose_string_internal, 3, 5, 0, |
| 1795 | doc: /* Internal use only. |
| 1796 | |
| 1797 | Compose text between indices START and END of STRING. |
| 1798 | Optional 4th and 5th arguments are COMPONENTS and MODIFICATION-FUNC |
| 1799 | for the composition. See `compose-string' for more details. */) |
| 1800 | (Lisp_Object string, Lisp_Object start, Lisp_Object end, Lisp_Object components, Lisp_Object modification_func) |
| 1801 | { |
| 1802 | CHECK_STRING (string); |
| 1803 | CHECK_NUMBER (start); |
| 1804 | CHECK_NUMBER (end); |
| 1805 | |
| 1806 | if (XINT (start) < 0 || |
| 1807 | XINT (start) > XINT (end) |
| 1808 | || XINT (end) > SCHARS (string)) |
| 1809 | args_out_of_range (start, end); |
| 1810 | |
| 1811 | compose_text (XINT (start), XINT (end), components, modification_func, string); |
| 1812 | return string; |
| 1813 | } |
| 1814 | |
| 1815 | DEFUN ("find-composition-internal", Ffind_composition_internal, |
| 1816 | Sfind_composition_internal, 4, 4, 0, |
| 1817 | doc: /* Internal use only. |
| 1818 | |
| 1819 | Return information about composition at or nearest to position POS. |
| 1820 | See `find-composition' for more details. */) |
| 1821 | (Lisp_Object pos, Lisp_Object limit, Lisp_Object string, Lisp_Object detail_p) |
| 1822 | { |
| 1823 | Lisp_Object prop, tail, gstring; |
| 1824 | ptrdiff_t start, end, from, to; |
| 1825 | int id; |
| 1826 | |
| 1827 | CHECK_NUMBER_COERCE_MARKER (pos); |
| 1828 | if (!NILP (limit)) |
| 1829 | { |
| 1830 | CHECK_NUMBER_COERCE_MARKER (limit); |
| 1831 | to = min (XINT (limit), ZV); |
| 1832 | } |
| 1833 | else |
| 1834 | to = -1; |
| 1835 | |
| 1836 | if (!NILP (string)) |
| 1837 | { |
| 1838 | CHECK_STRING (string); |
| 1839 | if (XINT (pos) < 0 || XINT (pos) > SCHARS (string)) |
| 1840 | args_out_of_range (string, pos); |
| 1841 | } |
| 1842 | else |
| 1843 | { |
| 1844 | if (XINT (pos) < BEGV || XINT (pos) > ZV) |
| 1845 | args_out_of_range (Fcurrent_buffer (), pos); |
| 1846 | } |
| 1847 | from = XINT (pos); |
| 1848 | |
| 1849 | if (!find_composition (from, to, &start, &end, &prop, string)) |
| 1850 | { |
| 1851 | if (!NILP (BVAR (current_buffer, enable_multibyte_characters)) |
| 1852 | && ! NILP (Vauto_composition_mode) |
| 1853 | && find_automatic_composition (from, to, &start, &end, &gstring, |
| 1854 | string)) |
| 1855 | return list3 (make_number (start), make_number (end), gstring); |
| 1856 | return Qnil; |
| 1857 | } |
| 1858 | if ((end <= XINT (pos) || start > XINT (pos))) |
| 1859 | { |
| 1860 | ptrdiff_t s, e; |
| 1861 | |
| 1862 | if (find_automatic_composition (from, to, &s, &e, &gstring, string) |
| 1863 | && (e <= XINT (pos) ? e > end : s < start)) |
| 1864 | return list3 (make_number (s), make_number (e), gstring); |
| 1865 | } |
| 1866 | if (!composition_valid_p (start, end, prop)) |
| 1867 | return list3 (make_number (start), make_number (end), Qnil); |
| 1868 | if (NILP (detail_p)) |
| 1869 | return list3 (make_number (start), make_number (end), Qt); |
| 1870 | |
| 1871 | if (composition_registered_p (prop)) |
| 1872 | id = COMPOSITION_ID (prop); |
| 1873 | else |
| 1874 | { |
| 1875 | ptrdiff_t start_byte = (NILP (string) |
| 1876 | ? CHAR_TO_BYTE (start) |
| 1877 | : string_char_to_byte (string, start)); |
| 1878 | id = get_composition_id (start, start_byte, end - start, prop, string); |
| 1879 | } |
| 1880 | |
| 1881 | if (id >= 0) |
| 1882 | { |
| 1883 | Lisp_Object components, relative_p, mod_func; |
| 1884 | enum composition_method method = composition_method (prop); |
| 1885 | int width = composition_table[id]->width; |
| 1886 | |
| 1887 | components = Fcopy_sequence (COMPOSITION_COMPONENTS (prop)); |
| 1888 | relative_p = (method == COMPOSITION_WITH_RULE_ALTCHARS |
| 1889 | ? Qnil : Qt); |
| 1890 | mod_func = COMPOSITION_MODIFICATION_FUNC (prop); |
| 1891 | tail = list4 (components, relative_p, mod_func, make_number (width)); |
| 1892 | } |
| 1893 | else |
| 1894 | tail = Qnil; |
| 1895 | |
| 1896 | return Fcons (make_number (start), Fcons (make_number (end), tail)); |
| 1897 | } |
| 1898 | |
| 1899 | \f |
| 1900 | void |
| 1901 | syms_of_composite (void) |
| 1902 | { |
| 1903 | int i; |
| 1904 | |
| 1905 | DEFSYM (Qcomposition, "composition"); |
| 1906 | |
| 1907 | /* Make a hash table for static composition. */ |
| 1908 | { |
| 1909 | Lisp_Object args[6]; |
| 1910 | |
| 1911 | args[0] = QCtest; |
| 1912 | args[1] = Qequal; |
| 1913 | args[2] = QCweakness; |
| 1914 | /* We used to make the hash table weak so that unreferenced |
| 1915 | compositions can be garbage-collected. But, usually once |
| 1916 | created compositions are repeatedly used in an Emacs session, |
| 1917 | and thus it's not worth to save memory in such a way. So, we |
| 1918 | make the table not weak. */ |
| 1919 | args[3] = Qnil; |
| 1920 | args[4] = QCsize; |
| 1921 | args[5] = make_number (311); |
| 1922 | composition_hash_table = Fmake_hash_table (6, args); |
| 1923 | staticpro (&composition_hash_table); |
| 1924 | } |
| 1925 | |
| 1926 | /* Make a hash table for glyph-string. */ |
| 1927 | { |
| 1928 | Lisp_Object args[6]; |
| 1929 | args[0] = QCtest; |
| 1930 | args[1] = Qequal; |
| 1931 | args[2] = QCweakness; |
| 1932 | args[3] = Qnil; |
| 1933 | args[4] = QCsize; |
| 1934 | args[5] = make_number (311); |
| 1935 | gstring_hash_table = Fmake_hash_table (6, args); |
| 1936 | staticpro (&gstring_hash_table); |
| 1937 | } |
| 1938 | |
| 1939 | staticpro (&gstring_work_headers); |
| 1940 | gstring_work_headers = make_uninit_vector (8); |
| 1941 | for (i = 0; i < 8; i++) |
| 1942 | ASET (gstring_work_headers, i, Fmake_vector (make_number (i + 2), Qnil)); |
| 1943 | staticpro (&gstring_work); |
| 1944 | gstring_work = Fmake_vector (make_number (10), Qnil); |
| 1945 | |
| 1946 | /* Text property `composition' should be nonsticky by default. */ |
| 1947 | Vtext_property_default_nonsticky |
| 1948 | = Fcons (Fcons (Qcomposition, Qt), Vtext_property_default_nonsticky); |
| 1949 | |
| 1950 | DEFVAR_LISP ("compose-chars-after-function", Vcompose_chars_after_function, |
| 1951 | doc: /* Function to adjust composition of buffer text. |
| 1952 | |
| 1953 | This function is called with three arguments: FROM, TO, and OBJECT. |
| 1954 | FROM and TO specify the range of text whose composition should be |
| 1955 | adjusted. OBJECT, if non-nil, is a string that contains the text. |
| 1956 | |
| 1957 | This function is called after a text with `composition' property is |
| 1958 | inserted or deleted to keep `composition' property of buffer text |
| 1959 | valid. |
| 1960 | |
| 1961 | The default value is the function `compose-chars-after'. */); |
| 1962 | Vcompose_chars_after_function = intern_c_string ("compose-chars-after"); |
| 1963 | |
| 1964 | DEFSYM (Qauto_composed, "auto-composed"); |
| 1965 | DEFSYM (Qauto_composition_function, "auto-composition-function"); |
| 1966 | |
| 1967 | DEFVAR_LISP ("auto-composition-mode", Vauto_composition_mode, |
| 1968 | doc: /* Non-nil if Auto-Composition mode is enabled. |
| 1969 | Use the command `auto-composition-mode' to change this variable. */); |
| 1970 | Vauto_composition_mode = Qt; |
| 1971 | |
| 1972 | DEFVAR_LISP ("auto-composition-function", Vauto_composition_function, |
| 1973 | doc: /* Function to call to compose characters automatically. |
| 1974 | This function is called from the display routine with four arguments: |
| 1975 | FROM, TO, WINDOW, and STRING. |
| 1976 | |
| 1977 | If STRING is nil, the function must compose characters in the region |
| 1978 | between FROM and TO in the current buffer. |
| 1979 | |
| 1980 | Otherwise, STRING is a string, and FROM and TO are indices into the |
| 1981 | string. In this case, the function must compose characters in the |
| 1982 | string. */); |
| 1983 | Vauto_composition_function = Qnil; |
| 1984 | |
| 1985 | DEFVAR_LISP ("composition-function-table", Vcomposition_function_table, |
| 1986 | doc: /* Char-table of functions for automatic character composition. |
| 1987 | For each character that has to be composed automatically with |
| 1988 | preceding and/or following characters, this char-table contains |
| 1989 | a function to call to compose that character. |
| 1990 | |
| 1991 | The element at index C in the table, if non-nil, is a list of |
| 1992 | composition rules of this form: ([PATTERN PREV-CHARS FUNC] ...) |
| 1993 | |
| 1994 | PATTERN is a regular expression which C and the surrounding |
| 1995 | characters must match. |
| 1996 | |
| 1997 | PREV-CHARS is a non-negative integer (less than 4) specifying how many |
| 1998 | characters before C to check the matching with PATTERN. If it is 0, |
| 1999 | PATTERN must match C and the following characters. If it is 1, |
| 2000 | PATTERN must match a character before C and the following characters. |
| 2001 | |
| 2002 | If PREV-CHARS is 0, PATTERN can be nil, which means that the |
| 2003 | single character C should be composed. |
| 2004 | |
| 2005 | FUNC is a function to return a glyph-string representing a |
| 2006 | composition of the characters that match PATTERN. It is |
| 2007 | called with one argument GSTRING. |
| 2008 | |
| 2009 | GSTRING is a template of a glyph-string to return. It is already |
| 2010 | filled with a proper header for the characters to compose, and |
| 2011 | glyphs corresponding to those characters one by one. The |
| 2012 | function must return a new glyph-string with the same header as |
| 2013 | GSTRING, or modify GSTRING itself and return it. |
| 2014 | |
| 2015 | See also the documentation of `auto-composition-mode'. */); |
| 2016 | Vcomposition_function_table = Fmake_char_table (Qnil, Qnil); |
| 2017 | |
| 2018 | defsubr (&Scompose_region_internal); |
| 2019 | defsubr (&Scompose_string_internal); |
| 2020 | defsubr (&Sfind_composition_internal); |
| 2021 | defsubr (&Scomposition_get_gstring); |
| 2022 | } |