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
10 This file is part of GNU Emacs.
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.
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.
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/>. */
28 #include "character.h"
31 #include "intervals.h"
34 #include "dispextern.h"
36 #include "termhooks.h"
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.
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).
55 We register a composition when it is displayed, or when the width
56 is required (for instance, to calculate columns).
58 LENGTH -- Length of the composition. This information is used to
59 check the validity of the composition.
61 COMPONENTS -- Character, string, vector, list, or nil.
63 If it is nil, characters in the text are composed relatively
64 according to their metrics in font glyphs.
66 If it is a character or a string, the character or characters
67 in the string are composed relatively.
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.
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
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.
86 COMPOSITION-ID --Identification number of the composition. It is
87 used as an index to composition_table for the composition.
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.
100 We use two tables to keep the information about composition;
101 composition_hash_table and composition_table.
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.
109 The latter is a table of pointers to `struct composition' indexed
110 by COMPOSITION-ID. This structure keeps the other information (see
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.
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
137 Lisp_Object Qcomposition
;
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
;
144 /* The current size of `composition_table'. */
145 static ptrdiff_t composition_table_size
;
147 /* Number of compositions currently made. */
148 ptrdiff_t n_compositions
;
150 /* Hash table for compositions. The key is COMPONENTS-VEC of
151 `composition' property. The value is the corresponding
153 Lisp_Object composition_hash_table
;
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
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.
166 If the composition is invalid, return -1. */
169 get_composition_id (ptrdiff_t charpos
, ptrdiff_t bytepos
, ptrdiff_t nchars
,
170 Lisp_Object prop
, Lisp_Object string
)
172 Lisp_Object id
, length
, components
, key
, *key_contents
;
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
;
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. */
188 GLYPH_LEN_MAX
= min ((INT_MAX
- 1) / 2,
189 min (PTRDIFF_MAX
, SIZE_MAX
) / MAX_MULTIBYTE_LENGTH
)
193 Form-A: ((LENGTH . COMPONENTS) . MODIFICATION-FUNC)
195 Form-B: (COMPOSITION-ID . (LENGTH COMPONENTS-VEC . MODIFICATION-FUNC))
197 if (nchars
== 0 || !CONSP (prop
))
198 goto invalid_composition
;
203 /* PROP should be Form-B. */
204 if (XINT (id
) < 0 || XINT (id
) >= n_compositions
)
205 goto invalid_composition
;
209 /* PROP should be Form-A.
210 Thus, ID should be (LENGTH . COMPONENTS). */
212 goto invalid_composition
;
214 if (!INTEGERP (length
) || XINT (length
) != nchars
)
215 goto invalid_composition
;
217 components
= XCDR (id
);
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
))
229 else if (NILP (components
))
231 key
= make_uninit_vector (nchars
);
232 if (STRINGP (string
))
233 for (i
= 0; i
< nchars
; i
++)
235 FETCH_STRING_CHAR_ADVANCE (ch
, string
, charpos
, bytepos
);
236 ASET (key
, i
, make_number (ch
));
239 for (i
= 0; i
< nchars
; i
++)
241 FETCH_CHAR_ADVANCE (ch
, charpos
, bytepos
);
242 ASET (key
, i
, make_number (ch
));
246 goto invalid_composition
;
248 hash_index
= hash_lookup (hash_table
, key
, &hash_code
);
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
);
258 XSETCDR (prop
, Fcons (make_number (nchars
), Fcons (key
, XCDR (prop
))));
262 /* This composition is a new one. We must register it. */
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
);
269 key_contents
= XVECTOR (key
)->contents
;
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 */
275 if (VECTORP (components
)
276 && ASIZE (components
) >= 2
277 && VECTORP (AREF (components
, 0)))
279 /* COMPONENTS is a glyph-string. */
280 ptrdiff_t len
= ASIZE (key
);
282 for (i
= 1; i
< len
; i
++)
283 if (! VECTORP (AREF (key
, i
)))
284 goto invalid_composition
;
286 else if (VECTORP (components
) || CONSP (components
))
288 ptrdiff_t len
= ASIZE (key
);
290 /* The number of elements should be odd. */
292 goto invalid_composition
;
293 /* All elements should be integers (character or encoded
294 composition rule). */
295 for (i
= 0; i
< len
; i
++)
297 if (!INTEGERP (key_contents
[i
]))
298 goto invalid_composition
;
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
);
306 XSETCDR (prop
, Fcons (make_number (nchars
), Fcons (key
, XCDR (prop
))));
308 /* Register the composition in composition_hash_table. */
309 hash_index
= hash_put (hash_table
, key
, id
, hash_code
);
311 method
= (NILP (components
)
312 ? COMPOSITION_RELATIVE
313 : ((INTEGERP (components
) || STRINGP (components
))
314 ? COMPOSITION_WITH_ALTCHARS
315 : COMPOSITION_WITH_RULE_ALTCHARS
));
317 glyph_len
= (method
== COMPOSITION_WITH_RULE_ALTCHARS
318 ? (ASIZE (key
) + 1) / 2
321 if (GLYPH_LEN_MAX
< glyph_len
)
322 memory_full (SIZE_MAX
);
324 /* Register the composition in composition_table. */
325 cmp
= xmalloc (sizeof *cmp
);
327 cmp
->method
= method
;
328 cmp
->hash_index
= hash_index
;
329 cmp
->glyph_len
= glyph_len
;
330 cmp
->offsets
= xnmalloc_atomic (glyph_len
, 2 * sizeof *cmp
->offsets
);
333 if (cmp
->method
!= COMPOSITION_WITH_RULE_ALTCHARS
)
335 /* Relative composition. */
337 for (i
= 0; i
< glyph_len
; i
++)
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
;
350 /* Rule-base composition. */
351 double leftmost
= 0.0, rightmost
;
353 ch
= XINT (key_contents
[0]);
354 rightmost
= ch
!= '\t' ? CHAR_WIDTH (ch
) : 1;
356 for (i
= 1; i
< glyph_len
; i
+= 2)
358 int rule
, gref
, nref
;
362 rule
= XINT (key_contents
[i
]);
363 ch
= XINT (key_contents
[i
+ 1]);
364 this_width
= ch
!= '\t' ? CHAR_WIDTH (ch
) : 1;
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
376 ---3---4---5--- baseline
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);
385 if (this_left
< leftmost
)
386 leftmost
= this_left
;
387 if (this_left
+ this_width
> rightmost
)
388 rightmost
= this_left
+ this_width
;
391 cmp
->width
= rightmost
- leftmost
;
392 if (cmp
->width
< (rightmost
- leftmost
))
393 /* To get a ceiling integer value. */
397 composition_table
[n_compositions
] = cmp
;
399 return n_compositions
++;
402 /* Would it be better to remove this `composition' property? */
407 /* Find a static composition at or nearest to position POS of OBJECT
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.
414 If there's no composition at POS and LIMIT is negative, return 0.
416 Otherwise, search for a composition forward (LIMIT > POS) or
417 backward (LIMIT < POS). In this case, LIMIT bounds the search.
419 If a composition is found, set *START, *END, and *PROP as above,
420 and return 1, else return 0.
422 This doesn't check the validity of composition. */
425 find_composition (ptrdiff_t pos
, ptrdiff_t limit
,
426 ptrdiff_t *start
, ptrdiff_t *end
,
427 Lisp_Object
*prop
, Lisp_Object object
)
431 if (get_property_and_range (pos
, Qcomposition
, prop
, start
, end
, object
))
434 if (limit
< 0 || limit
== pos
)
437 if (limit
> pos
) /* search forward */
439 val
= Fnext_single_property_change (make_number (pos
), Qcomposition
,
440 object
, make_number (limit
));
445 else /* search backward */
447 if (get_property_and_range (pos
- 1, Qcomposition
, prop
, start
, end
,
450 val
= Fprevious_single_property_change (make_number (pos
), Qcomposition
,
451 object
, make_number (limit
));
457 get_property_and_range (pos
, Qcomposition
, prop
, start
, end
, object
);
461 /* Run a proper function to adjust the composition sitting between
462 FROM and TO with property PROP. */
465 run_composition_function (ptrdiff_t from
, ptrdiff_t to
, Lisp_Object prop
)
468 ptrdiff_t start
, end
;
470 func
= COMPOSITION_MODIFICATION_FUNC (prop
);
471 /* If an invalid composition precedes or follows, try to make them
474 && find_composition (from
- 1, -1, &start
, &end
, &prop
, Qnil
)
475 && !composition_valid_p (start
, end
, prop
))
478 && find_composition (to
, -1, &start
, &end
, &prop
, Qnil
)
479 && !composition_valid_p (start
, end
, prop
))
481 if (!NILP (Ffboundp (func
)))
482 call2 (func
, make_number (from
), make_number (to
));
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).
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.
493 This function is called when a buffer text is changed. If the
494 change is deletion, FROM == TO. Otherwise, FROM < TO. */
497 update_compositions (ptrdiff_t from
, ptrdiff_t to
, int check_mask
)
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
;
505 if (inhibit_modification_hooks
)
508 /* If FROM and TO are not in a valid range, do nothing. */
509 if (! (BEGV
<= from
&& from
<= to
&& to
<= ZV
))
512 if (check_mask
& CHECK_HEAD
)
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. */
520 && find_composition (from
- 1, -1, &start
, &end
, &prop
, Qnil
)
521 && composition_valid_p (start
, end
, prop
))
527 Fput_text_property (make_number (from
), make_number (end
),
529 Fcons (XCAR (prop
), XCDR (prop
)), Qnil
);
530 run_composition_function (start
, end
, prop
);
534 && find_composition (from
, -1, &start
, &from
, &prop
, Qnil
)
535 && composition_valid_p (start
, from
, prop
))
539 run_composition_function (start
, from
, prop
);
543 if (check_mask
& CHECK_INSIDE
)
545 /* In this case, we are sure that (check & CHECK_TAIL) is also
546 nonzero. Thus, here we should check only compositions before
549 && find_composition (from
, to
, &start
, &from
, &prop
, Qnil
)
550 && composition_valid_p (start
, from
, prop
)
552 run_composition_function (start
, from
, prop
);
555 if (check_mask
& CHECK_TAIL
)
558 && find_composition (to
- 1, -1, &start
, &end
, &prop
, Qnil
)
559 && composition_valid_p (start
, end
, prop
))
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. */
568 Fput_text_property (make_number (start
), make_number (to
),
570 Fcons (XCAR (prop
), XCDR (prop
)), Qnil
);
573 run_composition_function (start
, end
, prop
);
576 && find_composition (to
, -1, &start
, &end
, &prop
, Qnil
)
577 && composition_valid_p (start
, end
, prop
))
579 run_composition_function (start
, end
, prop
);
583 if (min_pos
< max_pos
)
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
);
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'. */
603 make_composition_value_copy (Lisp_Object list
)
605 Lisp_Object plist
, val
;
607 for (; CONSP (list
); list
= XCDR (list
))
609 plist
= XCAR (XCDR (XCDR (XCAR (list
))));
610 while (CONSP (plist
) && CONSP (XCDR (plist
)))
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
));
621 /* Make text in the region between START and END a composition that
622 has COMPONENTS and MODIFICATION-FUNC.
624 If STRING is non-nil, then operate on characters contained between
625 indices START and END in STRING. */
628 compose_text (ptrdiff_t start
, ptrdiff_t end
, Lisp_Object components
,
629 Lisp_Object modification_func
, Lisp_Object string
)
633 prop
= Fcons (Fcons (make_number (end
- start
), components
),
635 Fput_text_property (make_number (start
), make_number (end
),
636 Qcomposition
, prop
, string
);
639 /* Lisp glyph-string handlers. */
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
645 static Lisp_Object gstring_hash_table
;
647 static Lisp_Object
gstring_lookup_cache (Lisp_Object
);
650 gstring_lookup_cache (Lisp_Object header
)
652 struct Lisp_Hash_Table
*h
= XHASH_TABLE (gstring_hash_table
);
653 ptrdiff_t i
= hash_lookup (h
, header
, NULL
);
655 return (i
>= 0 ? HASH_VALUE (h
, i
) : Qnil
);
659 composition_gstring_put_cache (Lisp_Object gstring
, ptrdiff_t len
)
661 struct Lisp_Hash_Table
*h
= XHASH_TABLE (gstring_hash_table
);
663 Lisp_Object header
, copy
;
666 header
= LGSTRING_HEADER (gstring
);
667 hash
= h
->test
.hashfn (&h
->test
, header
);
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
)))
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
));
687 composition_gstring_from_id (ptrdiff_t id
)
689 struct Lisp_Hash_Table
*h
= XHASH_TABLE (gstring_hash_table
);
691 return HASH_VALUE (h
, id
);
695 composition_gstring_p (Lisp_Object gstring
)
700 if (! VECTORP (gstring
) || ASIZE (gstring
) < 2)
702 header
= LGSTRING_HEADER (gstring
);
703 if (! VECTORP (header
) || ASIZE (header
) < 2)
705 if (! NILP (LGSTRING_FONT (gstring
))
706 && (! FONT_OBJECT_P (LGSTRING_FONT (gstring
))
707 && ! CODING_SYSTEM_P (LGSTRING_FONT (gstring
))))
709 for (i
= 1; i
< ASIZE (LGSTRING_HEADER (gstring
)); i
++)
710 if (! NATNUMP (AREF (LGSTRING_HEADER (gstring
), i
)))
712 if (! NILP (LGSTRING_ID (gstring
)) && ! NATNUMP (LGSTRING_ID (gstring
)))
714 for (i
= 0; i
< LGSTRING_GLYPH_LEN (gstring
); i
++)
716 Lisp_Object glyph
= LGSTRING_GLYPH (gstring
, i
);
719 if (! VECTORP (glyph
) || ASIZE (glyph
) != LGLYPH_SIZE
)
726 composition_gstring_width (Lisp_Object gstring
, ptrdiff_t from
, ptrdiff_t to
,
727 struct font_metrics
*metrics
)
734 Lisp_Object font_object
= LGSTRING_FONT (gstring
);
736 if (FONT_OBJECT_P (font_object
))
738 struct font
*font
= XFONT_OBJECT (font_object
);
740 metrics
->ascent
= font
->ascent
;
741 metrics
->descent
= font
->descent
;
746 metrics
->descent
= 0;
748 metrics
->width
= metrics
->lbearing
= metrics
->rbearing
= 0;
750 for (glyph
= lgstring_glyph_addr (gstring
, from
); from
< to
; from
++, glyph
++)
754 if (NILP (LGLYPH_ADJUSTMENT (*glyph
)))
755 width
+= LGLYPH_WIDTH (*glyph
);
757 width
+= LGLYPH_WADJUST (*glyph
);
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
)
770 x
= LGLYPH_DESCENT (*glyph
) + LGLYPH_YOFF (*glyph
);
771 if (metrics
->descent
< x
)
772 metrics
->descent
= x
;
779 static Lisp_Object gstring_work
;
780 static Lisp_Object gstring_work_headers
;
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
)
786 ptrdiff_t len
= to
- from
, i
;
789 error ("Attempt to shape zero-length text");
790 if (VECTORP (header
))
792 if (ASIZE (header
) != len
+ 1)
793 args_out_of_range (header
, make_number (len
+ 1));
798 header
= AREF (gstring_work_headers
, len
- 1);
800 header
= make_uninit_vector (len
+ 1);
803 ASET (header
, 0, font_object
);
804 for (i
= 0; i
< len
; i
++)
809 FETCH_CHAR_ADVANCE_NO_CHECK (c
, from
, from_byte
);
811 FETCH_STRING_CHAR_ADVANCE_NO_CHECK (c
, string
, from
, from_byte
);
812 ASET (header
, i
+ 1, make_number (c
));
818 fill_gstring_body (Lisp_Object gstring
)
820 Lisp_Object font_object
= LGSTRING_FONT (gstring
);
821 Lisp_Object header
= AREF (gstring
, 0);
822 ptrdiff_t len
= LGSTRING_CHAR_LEN (gstring
);
825 for (i
= 0; i
< len
; i
++)
827 Lisp_Object g
= LGSTRING_GLYPH (gstring
, i
);
828 int c
= XFASTINT (AREF (header
, i
+ 1));
833 LGSTRING_SET_GLYPH (gstring
, i
, g
);
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
))
840 font_fill_lglyph_metrics (g
, font_object
);
844 int width
= XFASTINT (CHAR_TABLE_REF (Vchar_width_table
, c
));
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);
853 LGLYPH_SET_ADJUSTMENT (g
, Qnil
);
855 if (i
< LGSTRING_GLYPH_LEN (gstring
))
856 LGSTRING_SET_GLYPH (gstring
, i
, Qnil
);
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. */
868 autocmp_chars (Lisp_Object rule
, ptrdiff_t charpos
, ptrdiff_t bytepos
,
869 ptrdiff_t limit
, struct window
*win
, struct face
*face
,
873 struct frame
*f
= XFRAME (win
->frame
);
874 Lisp_Object pos
= make_number (charpos
);
876 ptrdiff_t pt
= PT
, pt_byte
= PT_BYTE
;
877 Lisp_Object re
, font_object
, lgstring
;
880 record_unwind_save_match_data ();
884 else if (! STRINGP (re
)){
889 else if ((len
= fast_looking_at (re
, charpos
, bytepos
, limit
, -1, string
))
893 len
= BYTE_TO_CHAR (bytepos
+ len
) - charpos
;
895 len
= string_byte_to_char (string
, bytepos
+ len
) - charpos
;
902 to
= limit
= charpos
+ len
;
903 #ifdef HAVE_WINDOW_SYSTEM
904 if (FRAME_WINDOW_P (f
))
906 font_object
= font_range (charpos
, bytepos
, &to
, win
, face
, string
);
907 if (! FONT_OBJECT_P (font_object
)
910 && (fast_looking_at (re
, charpos
, bytepos
, to
, -1, string
) <= 0))){
917 #endif /* not HAVE_WINDOW_SYSTEM */
918 font_object
= win
->frame
;
919 lgstring
= Fcomposition_get_gstring (pos
, make_number (to
), font_object
,
921 if (NILP (LGSTRING_ID (lgstring
)))
923 /* Save point as marker before calling out to lisp. */
925 record_unwind_protect (restore_point_unwind
,
926 build_marker (current_buffer
, pt
, pt_byte
));
927 lgstring
= safe_call (6, Vauto_composition_function
, AREF (rule
, 2),
928 pos
, make_number (to
), font_object
, string
);
934 /* 1 iff the character C is composable. Characters of general
935 category Z? or C? are not composable except for ZWNJ and ZWJ. */
938 char_composable_p (int c
)
942 && (c
== 0x200C || c
== 0x200D
943 || (val
= CHAR_TABLE_REF (Vunicode_category_table
, c
),
944 (INTEGERP (val
) && (XINT (val
) <= UNICODE_CATEGORY_So
)))));
947 /* Update cmp_it->stop_pos to the next position after CHARPOS (and
948 BYTEPOS) where character composition may happen. If BYTEPOS is
949 negative, compute it. ENDPOS is a limit of searching. If it is
950 less than CHARPOS, search backward to ENDPOS+1 assuming that
951 set_iterator_to_next works in reverse order. In this case, if a
952 composition closest to CHARPOS is found, set cmp_it->stop_pos to
953 the last character of the composition.
955 If no composition is found, set cmp_it->ch to -2. If a static
956 composition is found, set cmp_it->ch to -1. Otherwise, set
957 cmp_it->ch to the character that triggers the automatic
961 composition_compute_stop_pos (struct composition_it
*cmp_it
, ptrdiff_t charpos
, ptrdiff_t bytepos
, ptrdiff_t endpos
, Lisp_Object string
)
963 ptrdiff_t start
, end
;
965 Lisp_Object prop
, val
;
966 /* This is from forward_to_next_line_start in xdisp.c. */
967 const int MAX_NEWLINE_DISTANCE
= 500;
969 if (charpos
< endpos
)
971 if (endpos
> charpos
+ MAX_NEWLINE_DISTANCE
)
972 endpos
= charpos
+ MAX_NEWLINE_DISTANCE
;
974 else if (endpos
< charpos
)
976 /* We search backward for a position to check composition. */
979 /* But we don't know where to stop the searching. */
980 endpos
= NILP (string
) ? BEGV
- 1 : -1;
981 /* Usually we don't reach ENDPOS because we stop searching
982 at an uncomposable character (NL, LRE, etc). */
987 cmp_it
->reversed_p
= 0;
988 cmp_it
->stop_pos
= endpos
;
989 if (charpos
== endpos
)
991 /* FIXME: Bidi is not yet handled well in static composition. */
993 && find_composition (charpos
, endpos
, &start
, &end
, &prop
, string
)
995 && composition_valid_p (start
, end
, prop
))
997 cmp_it
->stop_pos
= endpos
= start
;
1000 if (NILP (BVAR (current_buffer
, enable_multibyte_characters
))
1001 || NILP (Vauto_composition_mode
))
1006 bytepos
= CHAR_TO_BYTE (charpos
);
1008 bytepos
= string_char_to_byte (string
, charpos
);
1012 if (charpos
< endpos
)
1014 /* Forward search. */
1015 while (charpos
< endpos
)
1017 if (STRINGP (string
))
1018 FETCH_STRING_CHAR_ADVANCE (c
, string
, charpos
, bytepos
);
1020 FETCH_CHAR_ADVANCE (c
, charpos
, bytepos
);
1026 val
= CHAR_TABLE_REF (Vcomposition_function_table
, c
);
1032 for (ridx
= 0; CONSP (val
); val
= XCDR (val
), ridx
++)
1035 if (VECTORP (elt
) && ASIZE (elt
) == 3
1036 && NATNUMP (AREF (elt
, 1))
1037 && charpos
- 1 - XFASTINT (AREF (elt
, 1)) >= start
)
1042 cmp_it
->rule_idx
= ridx
;
1043 cmp_it
->lookback
= XFASTINT (AREF (elt
, 1));
1044 cmp_it
->stop_pos
= charpos
- 1 - cmp_it
->lookback
;
1050 if (charpos
== endpos
)
1052 /* We couldn't find a composition point before ENDPOS. But,
1053 some character after ENDPOS may be composed with
1054 characters before ENDPOS. So, we should stop at the safe
1056 charpos
= endpos
- MAX_AUTO_COMPOSITION_LOOKBACK
;
1057 if (charpos
< start
)
1061 else if (charpos
> endpos
)
1063 /* Search backward for a pattern that may be composed and the
1064 position of (possibly) the last character of the match is
1065 closest to (but not after) START. The reason for the last
1066 character is that set_iterator_to_next works in reverse order,
1067 and thus we must stop at the last character for composition
1071 /* Limit byte position used in fast_looking_at. This is the
1072 byte position of the character after START. */
1076 p
= BYTE_POS_ADDR (bytepos
);
1078 p
= SDATA (string
) + bytepos
;
1079 c
= STRING_CHAR_AND_LENGTH (p
, len
);
1080 limit
= bytepos
+ len
;
1081 while (char_composable_p (c
))
1083 val
= CHAR_TABLE_REF (Vcomposition_function_table
, c
);
1089 for (ridx
= 0; CONSP (val
); val
= XCDR (val
), ridx
++)
1092 if (VECTORP (elt
) && ASIZE (elt
) == 3
1093 && NATNUMP (AREF (elt
, 1))
1094 && charpos
- XFASTINT (AREF (elt
, 1)) > endpos
)
1096 ptrdiff_t back
= XFASTINT (AREF (elt
, 1));
1097 ptrdiff_t cpos
= charpos
- back
, bpos
;
1102 bpos
= (NILP (string
) ? CHAR_TO_BYTE (cpos
)
1103 : string_char_to_byte (string
, cpos
));
1104 if (STRINGP (AREF (elt
, 0)))
1105 blen
= fast_looking_at (AREF (elt
, 0), cpos
, bpos
,
1106 start
+ 1, limit
, string
);
1111 /* Make CPOS point to the last character of
1112 match. Note that BLEN is byte-length. */
1117 cpos
= BYTE_TO_CHAR (bpos
) - 1;
1119 cpos
= string_byte_to_char (string
, bpos
) - 1;
1121 back
= cpos
- (charpos
- back
);
1122 if (cmp_it
->stop_pos
< cpos
1123 || (cmp_it
->stop_pos
== cpos
1124 && cmp_it
->lookback
< back
))
1126 cmp_it
->rule_idx
= ridx
;
1127 cmp_it
->stop_pos
= cpos
;
1129 cmp_it
->lookback
= back
;
1130 cmp_it
->nchars
= back
+ 1;
1136 if (charpos
- 1 == endpos
)
1138 if (STRINGP (string
))
1141 while (! CHAR_HEAD_P (*p
))
1147 DEC_BOTH (charpos
, bytepos
);
1148 p
= BYTE_POS_ADDR (bytepos
);
1150 c
= STRING_CHAR (p
);
1152 if (cmp_it
->ch
>= 0)
1153 /* We found a position to check. */
1155 /* Skip all uncomposable characters. */
1158 while (charpos
- 1 > endpos
&& ! char_composable_p (c
))
1160 DEC_BOTH (charpos
, bytepos
);
1161 c
= FETCH_MULTIBYTE_CHAR (bytepos
);
1166 while (charpos
- 1 > endpos
&& ! char_composable_p (c
))
1169 while (! CHAR_HEAD_P (*p
))
1172 c
= STRING_CHAR (p
);
1176 cmp_it
->stop_pos
= charpos
;
1179 /* Check if the character at CHARPOS (and BYTEPOS) is composed
1180 (possibly with the following characters) on window W. ENDPOS limits
1181 characters to be composed. FACE, if non-NULL, is a base face of
1182 the character. If STRING is not nil, it is a string containing the
1183 character to check, and CHARPOS and BYTEPOS are indices in the
1184 string. In that case, FACE must not be NULL.
1186 If the character is composed, setup members of CMP_IT (id, nglyphs,
1187 from, to, reversed_p), and return true. Otherwise, update
1188 CMP_IT->stop_pos, and return false. */
1191 composition_reseat_it (struct composition_it
*cmp_it
, ptrdiff_t charpos
,
1192 ptrdiff_t bytepos
, ptrdiff_t endpos
, struct window
*w
,
1193 struct face
*face
, Lisp_Object string
)
1195 if (cmp_it
->ch
== -2)
1197 composition_compute_stop_pos (cmp_it
, charpos
, bytepos
, endpos
, string
);
1198 if (cmp_it
->ch
== -2 || cmp_it
->stop_pos
!= charpos
)
1199 /* The current position is not composed. */
1204 endpos
= NILP (string
) ? BEGV
: 0;
1208 /* We are looking at a static composition. */
1209 ptrdiff_t start
, end
;
1212 find_composition (charpos
, -1, &start
, &end
, &prop
, string
);
1213 cmp_it
->id
= get_composition_id (charpos
, bytepos
, end
- start
,
1216 goto no_composition
;
1217 cmp_it
->nchars
= end
- start
;
1218 cmp_it
->nglyphs
= composition_table
[cmp_it
->id
]->glyph_len
;
1222 Lisp_Object lgstring
= Qnil
;
1223 Lisp_Object val
, elt
;
1226 val
= CHAR_TABLE_REF (Vcomposition_function_table
, cmp_it
->ch
);
1227 for (i
= 0; i
< cmp_it
->rule_idx
; i
++, val
= XCDR (val
));
1228 if (charpos
< endpos
)
1230 for (; CONSP (val
); val
= XCDR (val
))
1233 if (! VECTORP (elt
) || ASIZE (elt
) != 3
1234 || ! INTEGERP (AREF (elt
, 1)))
1236 if (XFASTINT (AREF (elt
, 1)) != cmp_it
->lookback
)
1237 goto no_composition
;
1238 lgstring
= autocmp_chars (elt
, charpos
, bytepos
, endpos
,
1240 if (composition_gstring_p (lgstring
))
1243 /* Composition failed perhaps because the font doesn't
1244 support sufficient range of characters. Try the
1245 other composition rules if any. */
1247 cmp_it
->reversed_p
= 0;
1251 ptrdiff_t cpos
= charpos
, bpos
= bytepos
;
1253 cmp_it
->reversed_p
= 1;
1255 if (cmp_it
->lookback
> 0)
1257 cpos
= charpos
- cmp_it
->lookback
;
1258 if (STRINGP (string
))
1259 bpos
= string_char_to_byte (string
, cpos
);
1261 bpos
= CHAR_TO_BYTE (cpos
);
1263 lgstring
= autocmp_chars (elt
, cpos
, bpos
, charpos
+ 1, w
, face
,
1265 if (! composition_gstring_p (lgstring
)
1266 || cpos
+ LGSTRING_CHAR_LEN (lgstring
) - 1 != charpos
)
1267 /* Composition failed or didn't cover the current
1269 goto no_composition
;
1271 if (NILP (lgstring
))
1272 goto no_composition
;
1273 if (NILP (LGSTRING_ID (lgstring
)))
1274 lgstring
= composition_gstring_put_cache (lgstring
, -1);
1275 cmp_it
->id
= XINT (LGSTRING_ID (lgstring
));
1276 for (i
= 0; i
< LGSTRING_GLYPH_LEN (lgstring
); i
++)
1277 if (NILP (LGSTRING_GLYPH (lgstring
, i
)))
1279 cmp_it
->nglyphs
= i
;
1284 goto no_composition
;
1288 if (charpos
== endpos
)
1290 if (charpos
< endpos
)
1296 bytepos
+= BYTES_BY_CHAR_HEAD (*(SDATA (string
) + bytepos
));
1301 /* BYTEPOS is calculated in composition_compute_stop_pos */
1304 if (cmp_it
->reversed_p
)
1306 composition_compute_stop_pos (cmp_it
, charpos
, bytepos
, endpos
, string
);
1310 /* Update charpos, nchars, nbytes, and width of the current grapheme
1313 If the composition is static or automatic in L2R context, the
1314 cluster is identified by CMP_IT->from, and CHARPOS is the position
1315 of the first character of the cluster. In this case, update
1318 If the composition is automatic in R2L context, the cluster is
1319 identified by CMP_IT->to, and CHARPOS is the position of the last
1320 character of the cluster. In this case, update CMP_IT->from too.
1322 The return value is the character code of the first character of
1323 the cluster, or -1 if the composition is somehow broken. */
1326 composition_update_it (struct composition_it
*cmp_it
, ptrdiff_t charpos
, ptrdiff_t bytepos
, Lisp_Object string
)
1328 int i
, c
IF_LINT (= 0);
1332 /* static composition */
1333 struct composition
*cmp
= composition_table
[cmp_it
->id
];
1335 cmp_it
->charpos
= charpos
;
1336 cmp_it
->to
= cmp_it
->nglyphs
;
1337 if (cmp_it
->nglyphs
== 0)
1341 for (i
= 0; i
< cmp
->glyph_len
; i
++)
1342 /* TAB in a composition means display glyphs with padding
1343 space on the left or right. */
1344 if ((c
= COMPOSITION_GLYPH (cmp
, i
)) != '\t')
1349 cmp_it
->width
= cmp
->width
;
1350 charpos
+= cmp_it
->nchars
;
1351 if (STRINGP (string
))
1352 cmp_it
->nbytes
= string_char_to_byte (string
, charpos
) - bytepos
;
1354 cmp_it
->nbytes
= CHAR_TO_BYTE (charpos
) - bytepos
;
1358 /* Automatic composition. */
1359 Lisp_Object gstring
= composition_gstring_from_id (cmp_it
->id
);
1363 if (cmp_it
->nglyphs
== 0)
1365 cmp_it
->nchars
= LGSTRING_CHAR_LEN (gstring
);
1367 cmp_it
->from
= cmp_it
->to
= 0;
1370 if (! cmp_it
->reversed_p
)
1372 glyph
= LGSTRING_GLYPH (gstring
, cmp_it
->from
);
1373 from
= LGLYPH_FROM (glyph
);
1374 for (cmp_it
->to
= cmp_it
->from
+ 1; cmp_it
->to
< cmp_it
->nglyphs
;
1377 glyph
= LGSTRING_GLYPH (gstring
, cmp_it
->to
);
1378 if (LGLYPH_FROM (glyph
) != from
)
1381 cmp_it
->charpos
= charpos
;
1385 glyph
= LGSTRING_GLYPH (gstring
, cmp_it
->to
- 1);
1386 from
= LGLYPH_FROM (glyph
);
1387 cmp_it
->charpos
= charpos
- (LGLYPH_TO (glyph
) - from
);
1388 for (cmp_it
->from
= cmp_it
->to
- 1; cmp_it
->from
> 0;
1391 glyph
= LGSTRING_GLYPH (gstring
, cmp_it
->from
- 1);
1392 if (LGLYPH_FROM (glyph
) != from
)
1396 glyph
= LGSTRING_GLYPH (gstring
, cmp_it
->from
);
1397 cmp_it
->nchars
= LGLYPH_TO (glyph
) + 1 - from
;
1400 for (i
= cmp_it
->nchars
- 1; i
>= 0; i
--)
1402 c
= XINT (LGSTRING_CHAR (gstring
, from
+ i
));
1403 cmp_it
->nbytes
+= CHAR_BYTES (c
);
1404 cmp_it
->width
+= CHAR_WIDTH (c
);
1411 struct position_record
1413 ptrdiff_t pos
, pos_byte
;
1417 /* Update the members of POSITION to the next character boundary. */
1418 #define FORWARD_CHAR(POSITION, STOP) \
1421 if ((POSITION).pos == (STOP)) \
1423 (POSITION).p = GAP_END_ADDR; \
1424 (POSITION).pos_byte = GPT_BYTE; \
1428 (POSITION).pos_byte += BYTES_BY_CHAR_HEAD (*((POSITION).p)); \
1429 (POSITION).p += BYTES_BY_CHAR_HEAD (*((POSITION).p)); \
1433 /* Update the members of POSITION to the previous character boundary. */
1434 #define BACKWARD_CHAR(POSITION, STOP) \
1436 if ((POSITION).pos == (STOP)) \
1437 (POSITION).p = GPT_ADDR; \
1439 (POSITION).pos_byte--; \
1441 } while (! CHAR_HEAD_P (*((POSITION).p))); \
1445 /* This is like find_composition, but find an automatic composition
1446 instead. It is assured that POS is not within a static
1447 composition. If found, set *GSTRING to the glyph-string
1448 representing the composition, and return true. Otherwise, *GSTRING to
1449 Qnil, and return false. */
1452 find_automatic_composition (ptrdiff_t pos
, ptrdiff_t limit
,
1453 ptrdiff_t *start
, ptrdiff_t *end
,
1454 Lisp_Object
*gstring
, Lisp_Object string
)
1456 ptrdiff_t head
, tail
, stop
;
1457 /* Forward limit position of checking a composition taking a
1458 looking-back count into account. */
1459 ptrdiff_t fore_check_limit
;
1460 struct position_record cur
, prev
;
1464 bool need_adjustment
= 0;
1466 window
= Fget_buffer_window (Fcurrent_buffer (), Qnil
);
1469 w
= XWINDOW (window
);
1474 head
= BEGV
, tail
= ZV
, stop
= GPT
;
1475 cur
.pos_byte
= CHAR_TO_BYTE (cur
.pos
);
1476 cur
.p
= BYTE_POS_ADDR (cur
.pos_byte
);
1480 head
= 0, tail
= SCHARS (string
), stop
= -1;
1481 cur
.pos_byte
= string_char_to_byte (string
, cur
.pos
);
1482 cur
.p
= SDATA (string
) + cur
.pos_byte
;
1485 /* Finding a composition covering the character after POS is the
1486 same as setting LIMIT to POS. */
1489 fore_check_limit
= min (tail
, pos
+ 1 + MAX_AUTO_COMPOSITION_LOOKBACK
);
1491 fore_check_limit
= min (tail
, limit
+ MAX_AUTO_COMPOSITION_LOOKBACK
);
1493 /* Provided that we have these possible compositions now:
1495 POS: 1 2 3 4 5 6 7 8 9
1499 Here, it is known that characters after positions 1 and 9 can
1500 never be composed (i.e. ! char_composable_p (CH)), and
1501 composition A is an invalid one because it's partially covered by
1502 the valid composition C. And to know whether a composition is
1503 valid or not, the only way is to start searching forward from a
1504 position that can not be a tail part of composition (it's 2 in
1507 Now we have these cases (1 through 4):
1509 -- character after POS is ... --
1510 not composable composable
1511 LIMIT <= POS (1) (3)
1514 Among them, in case (2), we simply search forward from POS.
1516 In the other cases, we at first rewind back to the position where
1517 the previous character is not composable or the beginning of
1518 buffer (string), then search compositions forward. In case (1)
1519 and (3) we repeat this process until a composition is found. */
1523 c
= STRING_CHAR (cur
.p
);
1524 if (! char_composable_p (c
))
1526 if (limit
<= pos
) /* case (1) */
1529 if (cur
.pos
<= limit
)
1531 BACKWARD_CHAR (cur
, stop
);
1532 c
= STRING_CHAR (cur
.p
);
1533 } while (! char_composable_p (c
));
1534 fore_check_limit
= cur
.pos
+ 1;
1537 /* No need of rewinding back. */
1538 goto search_forward
;
1541 /* Rewind back to the position where we can safely search
1542 forward for compositions. It is assured that the character
1543 at cur.pos is composable. */
1544 while (head
< cur
.pos
)
1547 BACKWARD_CHAR (cur
, stop
);
1548 c
= STRING_CHAR (cur
.p
);
1549 if (! char_composable_p (c
))
1557 /* Now search forward. */
1559 prev
= cur
; /* remember the start of searching position. */
1560 while (cur
.pos
< fore_check_limit
)
1564 c
= STRING_CHAR (cur
.p
);
1565 for (val
= CHAR_TABLE_REF (Vcomposition_function_table
, c
);
1566 CONSP (val
); val
= XCDR (val
))
1568 Lisp_Object elt
= XCAR (val
);
1570 if (VECTORP (elt
) && ASIZE (elt
) == 3 && NATNUMP (AREF (elt
, 1)))
1572 EMACS_INT check_pos
= cur
.pos
- XFASTINT (AREF (elt
, 1));
1573 struct position_record check
;
1575 if (check_pos
< head
1576 || (limit
<= pos
? pos
< check_pos
1577 : limit
<= check_pos
))
1579 for (check
= cur
; check_pos
< check
.pos
; )
1580 BACKWARD_CHAR (check
, stop
);
1581 *gstring
= autocmp_chars (elt
, check
.pos
, check
.pos_byte
,
1582 tail
, w
, NULL
, string
);
1583 need_adjustment
= 1;
1584 if (NILP (*gstring
))
1586 /* As we have called Lisp, there's a possibility
1587 that buffer/string is relocated. */
1589 cur
.p
= BYTE_POS_ADDR (cur
.pos_byte
);
1591 cur
.p
= SDATA (string
) + cur
.pos_byte
;
1595 /* We found a candidate of a target composition. */
1597 *end
= check
.pos
+ LGSTRING_CHAR_LEN (*gstring
);
1600 : *start
<= pos
&& pos
< *end
)
1601 /* This is the target composition. */
1606 cur
.pos_byte
= CHAR_TO_BYTE (cur
.pos
);
1607 cur
.p
= BYTE_POS_ADDR (cur
.pos_byte
);
1611 cur
.pos_byte
= string_char_to_byte (string
, cur
.pos
);
1612 cur
.p
= SDATA (string
) + cur
.pos_byte
;
1619 /* We found no composition here. */
1620 FORWARD_CHAR (cur
, stop
);
1623 if (pos
< limit
) /* case (2) and (4)*/
1625 if (! NILP (*gstring
))
1627 if (prev
.pos
== head
)
1630 if (need_adjustment
)
1633 cur
.p
= BYTE_POS_ADDR (cur
.pos_byte
);
1635 cur
.p
= SDATA (string
) + cur
.pos_byte
;
1637 BACKWARD_CHAR (cur
, stop
);
1641 /* Return the adjusted point provided that point is moved from LAST_PT
1645 composition_adjust_point (ptrdiff_t last_pt
, ptrdiff_t new_pt
)
1647 ptrdiff_t i
, beg
, end
;
1650 if (new_pt
== BEGV
|| new_pt
== ZV
)
1653 /* At first check the static composition. */
1654 if (get_property_and_range (new_pt
, Qcomposition
, &val
, &beg
, &end
, Qnil
)
1655 && composition_valid_p (beg
, end
, val
))
1657 if (beg
< new_pt
/* && end > new_pt <- It's always the case. */
1658 && (last_pt
<= beg
|| last_pt
>= end
))
1659 return (new_pt
< last_pt
? beg
: end
);
1663 if (NILP (BVAR (current_buffer
, enable_multibyte_characters
))
1664 || NILP (Vauto_composition_mode
))
1667 /* Next check the automatic composition. */
1668 if (! find_automatic_composition (new_pt
, (ptrdiff_t) -1, &beg
, &end
, &val
,
1672 for (i
= 0; i
< LGSTRING_GLYPH_LEN (val
); i
++)
1674 Lisp_Object glyph
= LGSTRING_GLYPH (val
, i
);
1678 if (beg
+ LGLYPH_FROM (glyph
) == new_pt
)
1680 if (beg
+ LGLYPH_TO (glyph
) >= new_pt
)
1681 return (new_pt
< last_pt
1682 ? beg
+ LGLYPH_FROM (glyph
)
1683 : beg
+ LGLYPH_TO (glyph
) + 1);
1688 DEFUN ("composition-get-gstring", Fcomposition_get_gstring
,
1689 Scomposition_get_gstring
, 4, 4, 0,
1690 doc
: /* Return a glyph-string for characters between FROM and TO.
1691 If the glyph string is for graphic display, FONT-OBJECT must be
1692 a font-object to use for those characters.
1693 Otherwise (for terminal display), FONT-OBJECT must be a terminal ID, a
1694 frame, or nil for the selected frame's terminal device.
1696 If the optional 4th argument STRING is not nil, it is a string
1697 containing the target characters between indices FROM and TO,
1698 which are treated as in `substring'. Otherwise FROM and TO are
1699 character positions in current buffer; they can be in either order,
1700 and can be integers or markers.
1702 A glyph-string is a vector containing information about how to display
1703 a specific character sequence. The format is:
1704 [HEADER ID GLYPH ...]
1706 HEADER is a vector of this form:
1707 [FONT-OBJECT CHAR ...]
1709 FONT-OBJECT is a font-object for all glyphs in the glyph-string,
1710 or the terminal coding system of the specified terminal.
1711 CHARs are characters to be composed by GLYPHs.
1713 ID is an identification number of the glyph-string. It may be nil if
1716 GLYPH is a vector whose elements have this form:
1717 [ FROM-IDX TO-IDX C CODE WIDTH LBEARING RBEARING ASCENT DESCENT
1718 [ [X-OFF Y-OFF WADJUST] | nil] ]
1720 FROM-IDX and TO-IDX are used internally and should not be touched.
1721 C is the character of the glyph.
1722 CODE is the glyph-code of C in FONT-OBJECT.
1723 WIDTH thru DESCENT are the metrics (in pixels) of the glyph.
1724 X-OFF and Y-OFF are offsets to the base position for the glyph.
1725 WADJUST is the adjustment to the normal width of the glyph.
1727 If GLYPH is nil, the remaining elements of the glyph-string vector
1728 should be ignored. */)
1729 (Lisp_Object from
, Lisp_Object to
, Lisp_Object font_object
, Lisp_Object string
)
1731 Lisp_Object gstring
, header
;
1732 ptrdiff_t frompos
, frombyte
, topos
;
1734 if (! FONT_OBJECT_P (font_object
))
1736 struct coding_system
*coding
;
1737 struct terminal
*terminal
= get_terminal (font_object
, 1);
1739 coding
= ((TERMINAL_TERMINAL_CODING (terminal
)->common_flags
1740 & CODING_REQUIRE_ENCODING_MASK
)
1741 ? TERMINAL_TERMINAL_CODING (terminal
) : &safe_terminal_coding
);
1742 font_object
= CODING_ID_NAME (coding
->id
);
1747 if (NILP (BVAR (current_buffer
, enable_multibyte_characters
)))
1748 error ("Attempt to shape unibyte text");
1749 validate_region (&from
, &to
);
1750 frompos
= XFASTINT (from
);
1751 topos
= XFASTINT (to
);
1752 frombyte
= CHAR_TO_BYTE (frompos
);
1756 CHECK_STRING (string
);
1757 validate_subarray (string
, from
, to
, SCHARS (string
), &frompos
, &topos
);
1758 if (! STRING_MULTIBYTE (string
))
1759 error ("Attempt to shape unibyte text");
1760 frombyte
= string_char_to_byte (string
, frompos
);
1763 header
= fill_gstring_header (Qnil
, frompos
, frombyte
,
1764 topos
, font_object
, string
);
1765 gstring
= gstring_lookup_cache (header
);
1766 if (! NILP (gstring
))
1769 if (LGSTRING_GLYPH_LEN (gstring_work
) < topos
- frompos
)
1770 gstring_work
= Fmake_vector (make_number (topos
- frompos
+ 2), Qnil
);
1771 LGSTRING_SET_HEADER (gstring_work
, header
);
1772 LGSTRING_SET_ID (gstring_work
, Qnil
);
1773 fill_gstring_body (gstring_work
);
1774 return gstring_work
;
1778 /* Emacs Lisp APIs. */
1780 DEFUN ("compose-region-internal", Fcompose_region_internal
,
1781 Scompose_region_internal
, 2, 4, 0,
1782 doc
: /* Internal use only.
1784 Compose text in the region between START and END.
1785 Optional 3rd and 4th arguments are COMPONENTS and MODIFICATION-FUNC
1786 for the composition. See `compose-region' for more details. */)
1787 (Lisp_Object start
, Lisp_Object end
, Lisp_Object components
, Lisp_Object modification_func
)
1789 validate_region (&start
, &end
);
1790 if (!NILP (components
)
1791 && !INTEGERP (components
)
1792 && !CONSP (components
)
1793 && !STRINGP (components
))
1794 CHECK_VECTOR (components
);
1796 compose_text (XINT (start
), XINT (end
), components
, modification_func
, Qnil
);
1800 DEFUN ("compose-string-internal", Fcompose_string_internal
,
1801 Scompose_string_internal
, 3, 5, 0,
1802 doc
: /* Internal use only.
1804 Compose text between indices START and END of STRING, where
1805 START and END are treated as in `substring'. Optional 4th
1806 and 5th arguments are COMPONENTS and MODIFICATION-FUNC
1807 for the composition. See `compose-string' for more details. */)
1808 (Lisp_Object string
, Lisp_Object start
, Lisp_Object end
,
1809 Lisp_Object components
, Lisp_Object modification_func
)
1813 CHECK_STRING (string
);
1814 validate_subarray (string
, start
, end
, SCHARS (string
), &from
, &to
);
1815 compose_text (from
, to
, components
, modification_func
, string
);
1819 DEFUN ("find-composition-internal", Ffind_composition_internal
,
1820 Sfind_composition_internal
, 4, 4, 0,
1821 doc
: /* Internal use only.
1823 Return information about composition at or nearest to position POS.
1824 See `find-composition' for more details. */)
1825 (Lisp_Object pos
, Lisp_Object limit
, Lisp_Object string
, Lisp_Object detail_p
)
1827 Lisp_Object prop
, tail
, gstring
;
1828 ptrdiff_t start
, end
, from
, to
;
1831 CHECK_NUMBER_COERCE_MARKER (pos
);
1834 CHECK_NUMBER_COERCE_MARKER (limit
);
1835 to
= min (XINT (limit
), ZV
);
1842 CHECK_STRING (string
);
1843 if (XINT (pos
) < 0 || XINT (pos
) > SCHARS (string
))
1844 args_out_of_range (string
, pos
);
1848 if (XINT (pos
) < BEGV
|| XINT (pos
) > ZV
)
1849 args_out_of_range (Fcurrent_buffer (), pos
);
1853 if (!find_composition (from
, to
, &start
, &end
, &prop
, string
))
1855 if (!NILP (BVAR (current_buffer
, enable_multibyte_characters
))
1856 && ! NILP (Vauto_composition_mode
)
1857 && find_automatic_composition (from
, to
, &start
, &end
, &gstring
,
1859 return list3 (make_number (start
), make_number (end
), gstring
);
1862 if ((end
<= XINT (pos
) || start
> XINT (pos
)))
1866 if (find_automatic_composition (from
, to
, &s
, &e
, &gstring
, string
)
1867 && (e
<= XINT (pos
) ? e
> end
: s
< start
))
1868 return list3 (make_number (s
), make_number (e
), gstring
);
1870 if (!composition_valid_p (start
, end
, prop
))
1871 return list3 (make_number (start
), make_number (end
), Qnil
);
1872 if (NILP (detail_p
))
1873 return list3 (make_number (start
), make_number (end
), Qt
);
1875 if (composition_registered_p (prop
))
1876 id
= COMPOSITION_ID (prop
);
1879 ptrdiff_t start_byte
= (NILP (string
)
1880 ? CHAR_TO_BYTE (start
)
1881 : string_char_to_byte (string
, start
));
1882 id
= get_composition_id (start
, start_byte
, end
- start
, prop
, string
);
1887 Lisp_Object components
, relative_p
, mod_func
;
1888 enum composition_method method
= composition_method (prop
);
1889 int width
= composition_table
[id
]->width
;
1891 components
= Fcopy_sequence (COMPOSITION_COMPONENTS (prop
));
1892 relative_p
= (method
== COMPOSITION_WITH_RULE_ALTCHARS
1894 mod_func
= COMPOSITION_MODIFICATION_FUNC (prop
);
1895 tail
= list4 (components
, relative_p
, mod_func
, make_number (width
));
1900 return Fcons (make_number (start
), Fcons (make_number (end
), tail
));
1905 syms_of_composite (void)
1909 #include "composite.x"
1911 DEFSYM (Qcomposition
, "composition");
1913 /* Make a hash table for static composition. */
1915 Lisp_Object args
[6];
1919 args
[2] = QCweakness
;
1920 /* We used to make the hash table weak so that unreferenced
1921 compositions can be garbage-collected. But, usually once
1922 created compositions are repeatedly used in an Emacs session,
1923 and thus it's not worth to save memory in such a way. So, we
1924 make the table not weak. */
1927 args
[5] = make_number (311);
1928 composition_hash_table
= Fmake_hash_table (6, args
);
1929 staticpro (&composition_hash_table
);
1932 /* Make a hash table for glyph-string. */
1934 Lisp_Object args
[6];
1937 args
[2] = QCweakness
;
1940 args
[5] = make_number (311);
1941 gstring_hash_table
= Fmake_hash_table (6, args
);
1942 staticpro (&gstring_hash_table
);
1945 staticpro (&gstring_work_headers
);
1946 gstring_work_headers
= make_uninit_vector (8);
1947 for (i
= 0; i
< 8; i
++)
1948 ASET (gstring_work_headers
, i
, Fmake_vector (make_number (i
+ 2), Qnil
));
1949 staticpro (&gstring_work
);
1950 gstring_work
= Fmake_vector (make_number (10), Qnil
);
1952 /* Text property `composition' should be nonsticky by default. */
1953 Vtext_property_default_nonsticky
1954 = Fcons (Fcons (Qcomposition
, Qt
), Vtext_property_default_nonsticky
);
1956 DEFVAR_LISP ("compose-chars-after-function", Vcompose_chars_after_function
,
1957 doc
: /* Function to adjust composition of buffer text.
1959 This function is called with three arguments: FROM, TO, and OBJECT.
1960 FROM and TO specify the range of text whose composition should be
1961 adjusted. OBJECT, if non-nil, is a string that contains the text.
1963 This function is called after a text with `composition' property is
1964 inserted or deleted to keep `composition' property of buffer text
1967 The default value is the function `compose-chars-after'. */);
1968 Vcompose_chars_after_function
= intern_c_string ("compose-chars-after");
1970 DEFSYM (Qauto_composed
, "auto-composed");
1971 DEFSYM (Qauto_composition_function
, "auto-composition-function");
1973 DEFVAR_LISP ("auto-composition-mode", Vauto_composition_mode
,
1974 doc
: /* Non-nil if Auto-Composition mode is enabled.
1975 Use the command `auto-composition-mode' to change this variable. */);
1976 Vauto_composition_mode
= Qt
;
1978 DEFVAR_LISP ("auto-composition-function", Vauto_composition_function
,
1979 doc
: /* Function to call to compose characters automatically.
1980 This function is called from the display routine with four arguments:
1981 FROM, TO, WINDOW, and STRING.
1983 If STRING is nil, the function must compose characters in the region
1984 between FROM and TO in the current buffer.
1986 Otherwise, STRING is a string, and FROM and TO are indices into the
1987 string. In this case, the function must compose characters in the
1989 Vauto_composition_function
= Qnil
;
1991 DEFVAR_LISP ("composition-function-table", Vcomposition_function_table
,
1992 doc
: /* Char-table of functions for automatic character composition.
1993 For each character that has to be composed automatically with
1994 preceding and/or following characters, this char-table contains
1995 a function to call to compose that character.
1997 The element at index C in the table, if non-nil, is a list of
1998 composition rules of this form: ([PATTERN PREV-CHARS FUNC] ...)
2000 PATTERN is a regular expression which C and the surrounding
2001 characters must match.
2003 PREV-CHARS is a non-negative integer (less than 4) specifying how many
2004 characters before C to check the matching with PATTERN. If it is 0,
2005 PATTERN must match C and the following characters. If it is 1,
2006 PATTERN must match a character before C and the following characters.
2008 If PREV-CHARS is 0, PATTERN can be nil, which means that the
2009 single character C should be composed.
2011 FUNC is a function to return a glyph-string representing a
2012 composition of the characters that match PATTERN. It is
2013 called with one argument GSTRING.
2015 GSTRING is a template of a glyph-string to return. It is already
2016 filled with a proper header for the characters to compose, and
2017 glyphs corresponding to those characters one by one. The
2018 function must return a new glyph-string with the same header as
2019 GSTRING, or modify GSTRING itself and return it.
2021 See also the documentation of `auto-composition-mode'. */);
2022 Vcomposition_function_table
= Fmake_char_table (Qnil
, Qnil
);