1 /*
2 * Copyright © 2012,2013 Mozilla Foundation.
3 * Copyright © 2012,2013 Google, Inc.
4 *
5 * This is part of HarfBuzz, a text shaping library.
6 *
7 * Permission is hereby granted, without written agreement and without
8 * license or royalty fees, to use, copy, modify, and distribute this
9 * software and its documentation for any purpose, provided that the
10 * above copyright notice and the following two paragraphs appear in
11 * all copies of this software.
12 *
13 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
14 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
15 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
16 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
17 * DAMAGE.
18 *
19 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
20 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
21 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
22 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
23 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
24 *
25 * Mozilla Author(s): Jonathan Kew
26 * Google Author(s): Behdad Esfahbod
27 */
28
29 #include "hb.hh"
30 #include "hb-shaper-impl.hh"
31
32 #include "hb-coretext.h"
33 #include "hb-aat-layout.hh"
34 #include <math.h>
35
36
37 /**
38 * SECTION:hb-coretext
39 * @title: hb-coretext
40 * @short_description: CoreText integration
41 * @include: hb-coretext.h
42 *
43 * Functions for using HarfBuzz with the CoreText fonts.
44 **/
45
46 /* https://developer.apple.com/documentation/coretext/1508745-ctfontcreatewithgraphicsfont */
47 #define HB_CORETEXT_DEFAULT_FONT_SIZE 12.f
48
49 static CGFloat
50 coretext_font_size_from_ptem (float ptem)
51 {
52 /* CoreText points are CSS pixels (96 per inch),
53 * NOT typographic points (72 per inch).
54 *
55 * https://developer.apple.com/library/content/documentation/GraphicsAnimation/Conceptual/HighResolutionOSX/Explained/Explained.html
56 */
57 ptem *= 96.f / 72.f;
58 return ptem <= 0.f ? HB_CORETEXT_DEFAULT_FONT_SIZE : ptem;
59 }
60 static float
61 coretext_font_size_to_ptem (CGFloat size)
62 {
63 size *= 72.f / 96.f;
64 return size <= 0.f ? 0 : size;
65 }
66
67 static void
68 release_table_data (void *user_data)
69 {
70 CFDataRef cf_data = reinterpret_cast<CFDataRef> (user_data);
71 CFRelease(cf_data);
72 }
73
74 static hb_blob_t *
75 reference_table (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data)
76 {
77 CGFontRef cg_font = reinterpret_cast<CGFontRef> (user_data);
78 CFDataRef cf_data = CGFontCopyTableForTag (cg_font, tag);
79 if (unlikely (!cf_data))
80 return nullptr;
81
82 const char *data = reinterpret_cast<const char*> (CFDataGetBytePtr (cf_data));
83 const size_t length = CFDataGetLength (cf_data);
84 if (!data || !length)
85 {
86 CFRelease (cf_data);
87 return nullptr;
88 }
89
90 return hb_blob_create (data, length, HB_MEMORY_MODE_READONLY,
91 reinterpret_cast<void *> (const_cast<__CFData *> (cf_data)),
92 release_table_data);
93 }
94
95 static void
96 _hb_cg_font_release (void *data)
97 {
98 CGFontRelease ((CGFontRef) data);
99 }
100
101
102 static CTFontDescriptorRef
103 get_last_resort_font_desc ()
104 {
105 // TODO Handle allocation failures?
106 CTFontDescriptorRef last_resort = CTFontDescriptorCreateWithNameAndSize (CFSTR("LastResort"), 0);
107 CFArrayRef cascade_list = CFArrayCreate (kCFAllocatorDefault,
108 (const void **) &last_resort,
109 1,
110 &kCFTypeArrayCallBacks);
111 CFRelease (last_resort);
112 CFDictionaryRef attributes = CFDictionaryCreate (kCFAllocatorDefault,
113 (const void **) &kCTFontCascadeListAttribute,
114 (const void **) &cascade_list,
115 1,
116 &kCFTypeDictionaryKeyCallBacks,
117 &kCFTypeDictionaryValueCallBacks);
118 CFRelease (cascade_list);
119
120 CTFontDescriptorRef font_desc = CTFontDescriptorCreateWithAttributes (attributes);
121 CFRelease (attributes);
122 return font_desc;
123 }
124
125 static void
126 release_data (void *info, const void *data, size_t size)
127 {
128 assert (hb_blob_get_length ((hb_blob_t *) info) == size &&
129 hb_blob_get_data ((hb_blob_t *) info, nullptr) == data);
130
131 hb_blob_destroy ((hb_blob_t *) info);
132 }
133
134 static CGFontRef
135 create_cg_font (hb_face_t *face)
136 {
137 CGFontRef cg_font = nullptr;
138 if (face->destroy == _hb_cg_font_release)
139 {
140 cg_font = CGFontRetain ((CGFontRef) face->user_data);
141 }
142 else
143 {
144 hb_blob_t *blob = hb_face_reference_blob (face);
145 unsigned int blob_length;
146 const char *blob_data = hb_blob_get_data (blob, &blob_length);
147 if (unlikely (!blob_length))
148 DEBUG_MSG (CORETEXT, face, "Face has empty blob");
149
150 CGDataProviderRef provider = CGDataProviderCreateWithData (blob, blob_data, blob_length, &release_data);
151 if (likely (provider))
152 {
153 cg_font = CGFontCreateWithDataProvider (provider);
154 if (unlikely (!cg_font))
155 DEBUG_MSG (CORETEXT, face, "Face CGFontCreateWithDataProvider() failed");
156 CGDataProviderRelease (provider);
157 }
158 }
159 return cg_font;
160 }
161
162 static CTFontRef
163 create_ct_font (CGFontRef cg_font, CGFloat font_size)
164 {
165 CTFontRef ct_font = nullptr;
166
167 /* CoreText does not enable trak table usage / tracking when creating a CTFont
168 * using CTFontCreateWithGraphicsFont. The only way of enabling tracking seems
169 * to be through the CTFontCreateUIFontForLanguage call. */
170 CFStringRef cg_postscript_name = CGFontCopyPostScriptName (cg_font);
171 if (CFStringHasPrefix (cg_postscript_name, CFSTR (".SFNSText")) ||
172 CFStringHasPrefix (cg_postscript_name, CFSTR (".SFNSDisplay")))
173 {
174 #if MAC_OS_X_VERSION_MIN_REQUIRED < 1080
175 # define kCTFontUIFontSystem kCTFontSystemFontType
176 # define kCTFontUIFontEmphasizedSystem kCTFontEmphasizedSystemFontType
177 #endif
178 CTFontUIFontType font_type = kCTFontUIFontSystem;
179 if (CFStringHasSuffix (cg_postscript_name, CFSTR ("-Bold")))
180 font_type = kCTFontUIFontEmphasizedSystem;
181
182 ct_font = CTFontCreateUIFontForLanguage (font_type, font_size, nullptr);
183 CFStringRef ct_result_name = CTFontCopyPostScriptName(ct_font);
184 if (CFStringCompare (ct_result_name, cg_postscript_name, 0) != kCFCompareEqualTo)
185 {
186 CFRelease(ct_font);
187 ct_font = nullptr;
188 }
189 CFRelease (ct_result_name);
190 }
191 CFRelease (cg_postscript_name);
192
193 if (!ct_font)
194 ct_font = CTFontCreateWithGraphicsFont (cg_font, font_size, nullptr, nullptr);
195
196 if (unlikely (!ct_font)) {
197 DEBUG_MSG (CORETEXT, cg_font, "Font CTFontCreateWithGraphicsFont() failed");
198 return nullptr;
199 }
200
201 /* crbug.com/576941 and crbug.com/625902 and the investigation in the latter
202 * bug indicate that the cascade list reconfiguration occasionally causes
203 * crashes in CoreText on OS X 10.9, thus let's skip this step on older
204 * operating system versions. Except for the emoji font, where _not_
205 * reconfiguring the cascade list causes CoreText crashes. For details, see
206 * crbug.com/549610 */
207 // 0x00070000 stands for "kCTVersionNumber10_10", see CoreText.h
208 if (&CTGetCoreTextVersion != nullptr && CTGetCoreTextVersion() < 0x00070000) {
209 CFStringRef fontName = CTFontCopyPostScriptName (ct_font);
210 bool isEmojiFont = CFStringCompare (fontName, CFSTR("AppleColorEmoji"), 0) == kCFCompareEqualTo;
211 CFRelease (fontName);
212 if (!isEmojiFont)
213 return ct_font;
214 }
215
216 CFURLRef original_url = nullptr;
217 #if TARGET_OS_OSX && MAC_OS_X_VERSION_MIN_REQUIRED < 1060
218 ATSFontRef atsFont;
219 FSRef fsref;
220 OSStatus status;
221 atsFont = CTFontGetPlatformFont (ct_font, NULL);
222 status = ATSFontGetFileReference (atsFont, &fsref);
223 if (status == noErr)
224 original_url = CFURLCreateFromFSRef (NULL, &fsref);
225 #else
226 original_url = (CFURLRef) CTFontCopyAttribute (ct_font, kCTFontURLAttribute);
227 #endif
228
229 /* Create font copy with cascade list that has LastResort first; this speeds up CoreText
230 * font fallback which we don't need anyway. */
231 {
232 CTFontDescriptorRef last_resort_font_desc = get_last_resort_font_desc ();
233 CTFontRef new_ct_font = CTFontCreateCopyWithAttributes (ct_font, 0.0, nullptr, last_resort_font_desc);
234 CFRelease (last_resort_font_desc);
235 if (new_ct_font)
236 {
237 /* The CTFontCreateCopyWithAttributes call fails to stay on the same font
238 * when reconfiguring the cascade list and may switch to a different font
239 * when there are fonts that go by the same name, since the descriptor is
240 * just name and size.
241 *
242 * Avoid reconfiguring the cascade lists if the new font is outside the
243 * system locations that we cannot access from the sandboxed renderer
244 * process in Blink. This can be detected by the new file URL location
245 * that the newly found font points to. */
246 CFURLRef new_url = nullptr;
247 #if TARGET_OS_OSX && MAC_OS_X_VERSION_MIN_REQUIRED < 1060
248 atsFont = CTFontGetPlatformFont (new_ct_font, NULL);
249 status = ATSFontGetFileReference (atsFont, &fsref);
250 if (status == noErr)
251 new_url = CFURLCreateFromFSRef (NULL, &fsref);
252 #else
253 new_url = (CFURLRef) CTFontCopyAttribute (new_ct_font, kCTFontURLAttribute);
254 #endif
255 // Keep reconfigured font if URL cannot be retrieved (seems to be the case
256 // on Mac OS 10.12 Sierra), speculative fix for crbug.com/625606
257 if (!original_url || !new_url || CFEqual (original_url, new_url)) {
258 CFRelease (ct_font);
259 ct_font = new_ct_font;
260 } else {
261 CFRelease (new_ct_font);
262 DEBUG_MSG (CORETEXT, ct_font, "Discarding reconfigured CTFont, location changed.");
263 }
264 if (new_url)
265 CFRelease (new_url);
266 }
267 else
268 DEBUG_MSG (CORETEXT, ct_font, "Font copy with empty cascade list failed");
269 }
270
271 if (original_url)
272 CFRelease (original_url);
273 return ct_font;
274 }
275
276 hb_coretext_face_data_t *
277 _hb_coretext_shaper_face_data_create (hb_face_t *face)
278 {
279 CGFontRef cg_font = create_cg_font (face);
280
281 if (unlikely (!cg_font))
282 {
283 DEBUG_MSG (CORETEXT, face, "CGFont creation failed..");
284 return nullptr;
285 }
286
287 return (hb_coretext_face_data_t *) cg_font;
288 }
289
290 void
291 _hb_coretext_shaper_face_data_destroy (hb_coretext_face_data_t *data)
292 {
293 CFRelease ((CGFontRef) data);
294 }
295
296 hb_face_t *
297 hb_coretext_face_create (CGFontRef cg_font)
298 {
299 return hb_face_create_for_tables (reference_table, CGFontRetain (cg_font), _hb_cg_font_release);
300 }
301
302 /*
303 * Since: 0.9.10
304 */
305 CGFontRef
306 hb_coretext_face_get_cg_font (hb_face_t *face)
307 {
308 return (CGFontRef) (const void *) face->data.coretext;
309 }
310
311
312 hb_coretext_font_data_t *
313 _hb_coretext_shaper_font_data_create (hb_font_t *font)
314 {
315 hb_face_t *face = font->face;
316 const hb_coretext_face_data_t *face_data = face->data.coretext;
317 if (unlikely (!face_data)) return nullptr;
318 CGFontRef cg_font = (CGFontRef) (const void *) face->data.coretext;
319
320 CTFontRef ct_font = create_ct_font (cg_font, coretext_font_size_from_ptem (font->ptem));
321
322 if (unlikely (!ct_font))
323 {
324 DEBUG_MSG (CORETEXT, font, "CGFont creation failed..");
325 return nullptr;
326 }
327
328 return (hb_coretext_font_data_t *) ct_font;
329 }
330
331 void
332 _hb_coretext_shaper_font_data_destroy (hb_coretext_font_data_t *data)
333 {
334 CFRelease ((CTFontRef) data);
335 }
336
337 static const hb_coretext_font_data_t *
338 hb_coretext_font_data_sync (hb_font_t *font)
339 {
340 retry:
341 const hb_coretext_font_data_t *data = font->data.coretext;
342 if (unlikely (!data)) return nullptr;
343
344 if (fabs (CTFontGetSize((CTFontRef) data) - coretext_font_size_from_ptem (font->ptem)) > .5)
345 {
346 /* XXX-MT-bug
347 * Note that evaluating condition above can be dangerous if another thread
348 * got here first and destructed data. That's, as always, bad use pattern.
349 * If you modify the font (change font size), other threads must not be
350 * using it at the same time. However, since this check is delayed to
351 * when one actually tries to shape something, this is a XXX race condition
352 * (and the only one we have that I know of) right now. Ie. you modify the
353 * font size in one thread, then (supposedly safely) try to use it from two
354 * or more threads and BOOM! I'm not sure how to fix this. We want RCU.
355 */
356
357 /* Drop and recreate. */
358 /* If someone dropped it in the mean time, throw it away and don't touch it.
359 * Otherwise, destruct it. */
360 if (likely (font->data.coretext.cmpexch (const_cast<hb_coretext_font_data_t *> (data), nullptr)))
361 _hb_coretext_shaper_font_data_destroy (const_cast<hb_coretext_font_data_t *> (data));
362 else
363 goto retry;
364 }
365 return font->data.coretext;
366 }
367
368
369 /*
370 * Since: 1.7.2
371 */
372 hb_font_t *
373 hb_coretext_font_create (CTFontRef ct_font)
374 {
375 CGFontRef cg_font = CTFontCopyGraphicsFont (ct_font, nullptr);
376 hb_face_t *face = hb_coretext_face_create (cg_font);
377 CFRelease (cg_font);
378 hb_font_t *font = hb_font_create (face);
379 hb_face_destroy (face);
380
381 if (unlikely (hb_object_is_immutable (font)))
382 return font;
383
384 hb_font_set_ptem (font, coretext_font_size_to_ptem (CTFontGetSize(ct_font)));
385
386 /* Let there be dragons here... */
387 font->data.coretext.cmpexch (nullptr, (hb_coretext_font_data_t *) CFRetain (ct_font));
388
389 return font;
390 }
391
392 CTFontRef
393 hb_coretext_font_get_ct_font (hb_font_t *font)
394 {
395 const hb_coretext_font_data_t *data = hb_coretext_font_data_sync (font);
396 return data ? (CTFontRef) data : nullptr;
397 }
398
399
400 /*
401 * shaper
402 */
403
404 struct feature_record_t {
405 unsigned int feature;
406 unsigned int setting;
407 };
408
409 struct active_feature_t {
410 feature_record_t rec;
411 unsigned int order;
412
413 static int cmp (const void *pa, const void *pb) {
414 const active_feature_t *a = (const active_feature_t *) pa;
415 const active_feature_t *b = (const active_feature_t *) pb;
416 return a->rec.feature < b->rec.feature ? -1 : a->rec.feature > b->rec.feature ? 1 :
417 a->order < b->order ? -1 : a->order > b->order ? 1 :
418 a->rec.setting < b->rec.setting ? -1 : a->rec.setting > b->rec.setting ? 1 :
419 0;
420 }
421 bool operator== (const active_feature_t *f) {
422 return cmp (this, f) == 0;
423 }
424 };
425
426 struct feature_event_t {
427 unsigned int index;
428 bool start;
429 active_feature_t feature;
430
431 static int cmp (const void *pa, const void *pb) {
432 const feature_event_t *a = (const feature_event_t *) pa;
433 const feature_event_t *b = (const feature_event_t *) pb;
434 return a->index < b->index ? -1 : a->index > b->index ? 1 :
435 a->start < b->start ? -1 : a->start > b->start ? 1 :
436 active_feature_t::cmp (&a->feature, &b->feature);
437 }
438 };
439
440 struct range_record_t {
441 CTFontRef font;
442 unsigned int index_first; /* == start */
443 unsigned int index_last; /* == end - 1 */
444 };
445
446
447 hb_bool_t
448 _hb_coretext_shape (hb_shape_plan_t *shape_plan,
449 hb_font_t *font,
450 hb_buffer_t *buffer,
451 const hb_feature_t *features,
452 unsigned int num_features)
453 {
454 hb_face_t *face = font->face;
455 CGFontRef cg_font = (CGFontRef) (const void *) face->data.coretext;
456 CTFontRef ct_font = (CTFontRef) hb_coretext_font_data_sync (font);
457
458 CGFloat ct_font_size = CTFontGetSize (ct_font);
459 CGFloat x_mult = (CGFloat) font->x_scale / ct_font_size;
460 CGFloat y_mult = (CGFloat) font->y_scale / ct_font_size;
461
462 /* Attach marks to their bases, to match the 'ot' shaper.
463 * Adapted from a very old version of hb-ot-shape:hb_form_clusters().
464 * Note that this only makes us be closer to the 'ot' shaper,
465 * but by no means the same. For example, if there's
466 * B1 M1 B2 M2, and B1-B2 form a ligature, M2's cluster will
467 * continue pointing to B2 even though B2 was merged into B1's
468 * cluster... */
469 if (buffer->cluster_level == HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES)
470 {
471 hb_unicode_funcs_t *unicode = buffer->unicode;
472 unsigned int count = buffer->len;
473 hb_glyph_info_t *info = buffer->info;
474 for (unsigned int i = 1; i < count; i++)
475 if (HB_UNICODE_GENERAL_CATEGORY_IS_MARK (unicode->general_category (info[i].codepoint)))
476 buffer->merge_clusters (i - 1, i + 1);
477 }
478
479 hb_vector_t<feature_record_t> feature_records;
480 hb_vector_t<range_record_t> range_records;
481
482 /*
483 * Set up features.
484 * (copied + modified from code from hb-uniscribe.cc)
485 */
486 if (num_features)
487 {
488 /* Sort features by start/end events. */
489 hb_vector_t<feature_event_t> feature_events;
490 for (unsigned int i = 0; i < num_features; i++)
491 {
492 const hb_aat_feature_mapping_t * mapping = hb_aat_layout_find_feature_mapping (features[i].tag);
493 if (!mapping)
494 continue;
495
496 active_feature_t feature;
497 feature.rec.feature = mapping->aatFeatureType;
498 feature.rec.setting = features[i].value ? mapping->selectorToEnable : mapping->selectorToDisable;
499 feature.order = i;
500
501 feature_event_t *event;
502
503 event = feature_events.push ();
504 event->index = features[i].start;
505 event->start = true;
506 event->feature = feature;
507
508 event = feature_events.push ();
509 event->index = features[i].end;
510 event->start = false;
511 event->feature = feature;
512 }
513 feature_events.qsort ();
514 /* Add a strategic final event. */
515 {
516 active_feature_t feature;
517 feature.rec.feature = HB_TAG_NONE;
518 feature.rec.setting = 0;
519 feature.order = num_features + 1;
520
521 feature_event_t *event = feature_events.push ();
522 event->index = 0; /* This value does magic. */
523 event->start = false;
524 event->feature = feature;
525 }
526
527 /* Scan events and save features for each range. */
528 hb_vector_t<active_feature_t> active_features;
529 unsigned int last_index = 0;
530 for (unsigned int i = 0; i < feature_events.length; i++)
531 {
532 feature_event_t *event = &feature_events[i];
533
534 if (event->index != last_index)
535 {
536 /* Save a snapshot of active features and the range. */
537 range_record_t *range = range_records.push ();
538
539 if (active_features.length)
540 {
541 CFMutableArrayRef features_array = CFArrayCreateMutable(kCFAllocatorDefault, 0, &kCFTypeArrayCallBacks);
542
543 /* TODO sort and resolve conflicting features? */
544 /* active_features.qsort (); */
545 for (unsigned int j = 0; j < active_features.length; j++)
546 {
547 CFStringRef keys[] = {
548 kCTFontFeatureTypeIdentifierKey,
549 kCTFontFeatureSelectorIdentifierKey
550 };
551 CFNumberRef values[] = {
552 CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &active_features[j].rec.feature),
553 CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &active_features[j].rec.setting)
554 };
555 static_assert ((ARRAY_LENGTH_CONST (keys) == ARRAY_LENGTH_CONST (values)), "");
556 CFDictionaryRef dict = CFDictionaryCreate (kCFAllocatorDefault,
557 (const void **) keys,
558 (const void **) values,
559 ARRAY_LENGTH (keys),
560 &kCFTypeDictionaryKeyCallBacks,
561 &kCFTypeDictionaryValueCallBacks);
562 for (unsigned int i = 0; i < ARRAY_LENGTH (values); i++)
563 CFRelease (values[i]);
564
565 CFArrayAppendValue (features_array, dict);
566 CFRelease (dict);
567
568 }
569
570 CFDictionaryRef attributes = CFDictionaryCreate (kCFAllocatorDefault,
571 (const void **) &kCTFontFeatureSettingsAttribute,
572 (const void **) &features_array,
573 1,
574 &kCFTypeDictionaryKeyCallBacks,
575 &kCFTypeDictionaryValueCallBacks);
576 CFRelease (features_array);
577
578 CTFontDescriptorRef font_desc = CTFontDescriptorCreateWithAttributes (attributes);
579 CFRelease (attributes);
580
581 range->font = CTFontCreateCopyWithAttributes (ct_font, 0.0, nullptr, font_desc);
582 CFRelease (font_desc);
583 }
584 else
585 {
586 range->font = nullptr;
587 }
588
589 range->index_first = last_index;
590 range->index_last = event->index - 1;
591
592 last_index = event->index;
593 }
594
595 if (event->start)
596 {
597 active_features.push (event->feature);
598 } else {
599 active_feature_t *feature = active_features.find (&event->feature);
600 if (feature)
601 active_features.remove (feature - active_features.arrayZ ());
602 }
603 }
604 }
605
606 unsigned int scratch_size;
607 hb_buffer_t::scratch_buffer_t *scratch = buffer->get_scratch_buffer (&scratch_size);
608
609 #define ALLOCATE_ARRAY(Type, name, len, on_no_room) \
610 Type *name = (Type *) scratch; \
611 { \
612 unsigned int _consumed = DIV_CEIL ((len) * sizeof (Type), sizeof (*scratch)); \
613 if (unlikely (_consumed > scratch_size)) \
614 { \
615 on_no_room; \
616 assert (0); \
617 } \
618 scratch += _consumed; \
619 scratch_size -= _consumed; \
620 }
621
622 ALLOCATE_ARRAY (UniChar, pchars, buffer->len * 2, /*nothing*/);
623 unsigned int chars_len = 0;
624 for (unsigned int i = 0; i < buffer->len; i++) {
625 hb_codepoint_t c = buffer->info[i].codepoint;
626 if (likely (c <= 0xFFFFu))
627 pchars[chars_len++] = c;
628 else if (unlikely (c > 0x10FFFFu))
629 pchars[chars_len++] = 0xFFFDu;
630 else {
631 pchars[chars_len++] = 0xD800u + ((c - 0x10000u) >> 10);
632 pchars[chars_len++] = 0xDC00u + ((c - 0x10000u) & ((1u << 10) - 1));
633 }
634 }
635
636 ALLOCATE_ARRAY (unsigned int, log_clusters, chars_len, /*nothing*/);
637 chars_len = 0;
638 for (unsigned int i = 0; i < buffer->len; i++)
639 {
640 hb_codepoint_t c = buffer->info[i].codepoint;
641 unsigned int cluster = buffer->info[i].cluster;
642 log_clusters[chars_len++] = cluster;
643 if (hb_in_range (c, 0x10000u, 0x10FFFFu))
644 log_clusters[chars_len++] = cluster; /* Surrogates. */
645 }
646
647 #define FAIL(...) \
648 HB_STMT_START { \
649 DEBUG_MSG (CORETEXT, nullptr, __VA_ARGS__); \
650 ret = false; \
651 goto fail; \
652 } HB_STMT_END;
653
654 bool ret = true;
655 CFStringRef string_ref = nullptr;
656 CTLineRef line = nullptr;
657
658 if (false)
659 {
660 resize_and_retry:
661 DEBUG_MSG (CORETEXT, buffer, "Buffer resize");
662 /* string_ref uses the scratch-buffer for backing store, and line references
663 * string_ref (via attr_string). We must release those before resizing buffer. */
664 assert (string_ref);
665 assert (line);
666 CFRelease (string_ref);
667 CFRelease (line);
668 string_ref = nullptr;
669 line = nullptr;
670
671 /* Get previous start-of-scratch-area, that we use later for readjusting
672 * our existing scratch arrays. */
673 unsigned int old_scratch_used;
674 hb_buffer_t::scratch_buffer_t *old_scratch;
675 old_scratch = buffer->get_scratch_buffer (&old_scratch_used);
676 old_scratch_used = scratch - old_scratch;
677
678 if (unlikely (!buffer->ensure (buffer->allocated * 2)))
679 FAIL ("Buffer resize failed");
680
681 /* Adjust scratch, pchars, and log_cluster arrays. This is ugly, but really the
682 * cleanest way to do without completely restructuring the rest of this shaper. */
683 scratch = buffer->get_scratch_buffer (&scratch_size);
684 pchars = reinterpret_cast<UniChar *> (((char *) scratch + ((char *) pchars - (char *) old_scratch)));
685 log_clusters = reinterpret_cast<unsigned int *> (((char *) scratch + ((char *) log_clusters - (char *) old_scratch)));
686 scratch += old_scratch_used;
687 scratch_size -= old_scratch_used;
688 }
689 {
690 string_ref = CFStringCreateWithCharactersNoCopy (nullptr,
691 pchars, chars_len,
692 kCFAllocatorNull);
693 if (unlikely (!string_ref))
694 FAIL ("CFStringCreateWithCharactersNoCopy failed");
695
696 /* Create an attributed string, populate it, and create a line from it, then release attributed string. */
697 {
698 CFMutableAttributedStringRef attr_string = CFAttributedStringCreateMutable (kCFAllocatorDefault,
699 chars_len);
700 if (unlikely (!attr_string))
701 FAIL ("CFAttributedStringCreateMutable failed");
702 CFAttributedStringReplaceString (attr_string, CFRangeMake (0, 0), string_ref);
703 if (HB_DIRECTION_IS_VERTICAL (buffer->props.direction))
704 {
705 CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
706 kCTVerticalFormsAttributeName, kCFBooleanTrue);
707 }
708
709 if (buffer->props.language)
710 {
711 /* What's the iOS equivalent of this check?
712 * The symbols was introduced in iOS 7.0.
713 * At any rate, our fallback is safe and works fine. */
714 #if MAC_OS_X_VERSION_MIN_REQUIRED < 1090
715 # define kCTLanguageAttributeName CFSTR ("NSLanguage")
716 #endif
717 CFStringRef lang = CFStringCreateWithCStringNoCopy (kCFAllocatorDefault,
718 hb_language_to_string (buffer->props.language),
719 kCFStringEncodingUTF8,
720 kCFAllocatorNull);
721 if (unlikely (!lang))
722 {
723 CFRelease (attr_string);
724 FAIL ("CFStringCreateWithCStringNoCopy failed");
725 }
726 CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
727 kCTLanguageAttributeName, lang);
728 CFRelease (lang);
729 }
730 CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
731 kCTFontAttributeName, ct_font);
732
733 if (num_features && range_records.length)
734 {
735 unsigned int start = 0;
736 range_record_t *last_range = &range_records[0];
737 for (unsigned int k = 0; k < chars_len; k++)
738 {
739 range_record_t *range = last_range;
740 while (log_clusters[k] < range->index_first)
741 range--;
742 while (log_clusters[k] > range->index_last)
743 range++;
744 if (range != last_range)
745 {
746 if (last_range->font)
747 CFAttributedStringSetAttribute (attr_string, CFRangeMake (start, k - start),
748 kCTFontAttributeName, last_range->font);
749
750 start = k;
751 }
752
753 last_range = range;
754 }
755 if (start != chars_len && last_range->font)
756 CFAttributedStringSetAttribute (attr_string, CFRangeMake (start, chars_len - start),
757 kCTFontAttributeName, last_range->font);
758 }
759 /* Enable/disable kern if requested.
760 *
761 * Note: once kern is disabled, reenabling it doesn't currently seem to work in CoreText.
762 */
763 if (num_features)
764 {
765 unsigned int zeroint = 0;
766 CFNumberRef zero = CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &zeroint);
767 for (unsigned int i = 0; i < num_features; i++)
768 {
769 const hb_feature_t &feature = features[i];
770 if (feature.tag == HB_TAG('k','e','r','n') &&
771 feature.start < chars_len && feature.start < feature.end)
772 {
773 CFRange feature_range = CFRangeMake (feature.start,
774 MIN (feature.end, chars_len) - feature.start);
775 if (feature.value)
776 CFAttributedStringRemoveAttribute (attr_string, feature_range, kCTKernAttributeName);
777 else
778 CFAttributedStringSetAttribute (attr_string, feature_range, kCTKernAttributeName, zero);
779 }
780 }
781 CFRelease (zero);
782 }
783
784 int level = HB_DIRECTION_IS_FORWARD (buffer->props.direction) ? 0 : 1;
785 CFNumberRef level_number = CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &level);
786 #if MAC_OS_X_VERSION_MIN_REQUIRED < 1060
787 extern const CFStringRef kCTTypesetterOptionForcedEmbeddingLevel;
788 #endif
789 CFDictionaryRef options = CFDictionaryCreate (kCFAllocatorDefault,
790 (const void **) &kCTTypesetterOptionForcedEmbeddingLevel,
791 (const void **) &level_number,
792 1,
793 &kCFTypeDictionaryKeyCallBacks,
794 &kCFTypeDictionaryValueCallBacks);
795 CFRelease (level_number);
796 if (unlikely (!options))
797 {
798 CFRelease (attr_string);
799 FAIL ("CFDictionaryCreate failed");
800 }
801
802 CTTypesetterRef typesetter = CTTypesetterCreateWithAttributedStringAndOptions (attr_string, options);
803 CFRelease (options);
804 CFRelease (attr_string);
805 if (unlikely (!typesetter))
806 FAIL ("CTTypesetterCreateWithAttributedStringAndOptions failed");
807
808 line = CTTypesetterCreateLine (typesetter, CFRangeMake(0, 0));
809 CFRelease (typesetter);
810 if (unlikely (!line))
811 FAIL ("CTTypesetterCreateLine failed");
812 }
813
814 CFArrayRef glyph_runs = CTLineGetGlyphRuns (line);
815 unsigned int num_runs = CFArrayGetCount (glyph_runs);
816 DEBUG_MSG (CORETEXT, nullptr, "Num runs: %d", num_runs);
817
818 buffer->len = 0;
819 uint32_t status_and = ~0, status_or = 0;
820 double advances_so_far = 0;
821 /* For right-to-left runs, CoreText returns the glyphs positioned such that
822 * any trailing whitespace is to the left of (0,0). Adjust coordinate system
823 * to fix for that. Test with any RTL string with trailing spaces.
824 * https://crbug.com/469028
825 */
826 if (HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
827 {
828 advances_so_far -= CTLineGetTrailingWhitespaceWidth (line);
829 if (HB_DIRECTION_IS_VERTICAL (buffer->props.direction))
830 advances_so_far = -advances_so_far;
831 }
832
833 const CFRange range_all = CFRangeMake (0, 0);
834
835 for (unsigned int i = 0; i < num_runs; i++)
836 {
837 CTRunRef run = static_cast<CTRunRef>(CFArrayGetValueAtIndex (glyph_runs, i));
838 CTRunStatus run_status = CTRunGetStatus (run);
839 status_or |= run_status;
840 status_and &= run_status;
841 DEBUG_MSG (CORETEXT, run, "CTRunStatus: %x", run_status);
842 double run_advance = CTRunGetTypographicBounds (run, range_all, nullptr, nullptr, nullptr);
843 if (HB_DIRECTION_IS_VERTICAL (buffer->props.direction))
844 run_advance = -run_advance;
845 DEBUG_MSG (CORETEXT, run, "Run advance: %g", run_advance);
846
847 /* CoreText does automatic font fallback (AKA "cascading") for characters
848 * not supported by the requested font, and provides no way to turn it off,
849 * so we must detect if the returned run uses a font other than the requested
850 * one and fill in the buffer with .notdef glyphs instead of random glyph
851 * indices from a different font.
852 */
853 CFDictionaryRef attributes = CTRunGetAttributes (run);
854 CTFontRef run_ct_font = static_cast<CTFontRef>(CFDictionaryGetValue (attributes, kCTFontAttributeName));
855 if (!CFEqual (run_ct_font, ct_font))
856 {
857 /* The run doesn't use our main font instance. We have to figure out
858 * whether font fallback happened, or this is just CoreText giving us
859 * another CTFont using the same underlying CGFont. CoreText seems
860 * to do that in a variety of situations, one of which being vertical
861 * text, but also perhaps for caching reasons.
862 *
863 * First, see if it uses any of our subfonts created to set font features...
864 *
865 * Next, compare the CGFont to the one we used to create our fonts.
866 * Even this doesn't work all the time.
867 *
868 * Finally, we compare PS names, which I don't think are unique...
869 *
870 * Looks like if we really want to be sure here we have to modify the
871 * font to change the name table, similar to what we do in the uniscribe
872 * backend.
873 *
874 * However, even that wouldn't work if we were passed in the CGFont to
875 * construct a hb_face to begin with.
876 *
877 * See: https://github.com/harfbuzz/harfbuzz/pull/36
878 *
879 * Also see: https://bugs.chromium.org/p/chromium/issues/detail?id=597098
880 */
881 bool matched = false;
882 for (unsigned int i = 0; i < range_records.length; i++)
883 if (range_records[i].font && CFEqual (run_ct_font, range_records[i].font))
884 {
885 matched = true;
886 break;
887 }
888 if (!matched)
889 {
890 CGFontRef run_cg_font = CTFontCopyGraphicsFont (run_ct_font, nullptr);
891 if (run_cg_font)
892 {
893 matched = CFEqual (run_cg_font, cg_font);
894 CFRelease (run_cg_font);
895 }
896 }
897 if (!matched)
898 {
899 CFStringRef font_ps_name = CTFontCopyName (ct_font, kCTFontPostScriptNameKey);
900 CFStringRef run_ps_name = CTFontCopyName (run_ct_font, kCTFontPostScriptNameKey);
901 CFComparisonResult result = CFStringCompare (run_ps_name, font_ps_name, 0);
902 CFRelease (run_ps_name);
903 CFRelease (font_ps_name);
904 if (result == kCFCompareEqualTo)
905 matched = true;
906 }
907 if (!matched)
908 {
909 CFRange range = CTRunGetStringRange (run);
910 DEBUG_MSG (CORETEXT, run, "Run used fallback font: %ld..%ld",
911 range.location, range.location + range.length);
912 if (!buffer->ensure_inplace (buffer->len + range.length))
913 goto resize_and_retry;
914 hb_glyph_info_t *info = buffer->info + buffer->len;
915
916 hb_codepoint_t notdef = 0;
917 hb_direction_t dir = buffer->props.direction;
918 hb_position_t x_advance, y_advance, x_offset, y_offset;
919 hb_font_get_glyph_advance_for_direction (font, notdef, dir, &x_advance, &y_advance);
920 hb_font_get_glyph_origin_for_direction (font, notdef, dir, &x_offset, &y_offset);
921 hb_position_t advance = x_advance + y_advance;
922 x_offset = -x_offset;
923 y_offset = -y_offset;
924
925 unsigned int old_len = buffer->len;
926 for (CFIndex j = range.location; j < range.location + range.length; j++)
927 {
928 UniChar ch = CFStringGetCharacterAtIndex (string_ref, j);
929 if (hb_in_range<UniChar> (ch, 0xDC00u, 0xDFFFu) && range.location < j)
930 {
931 ch = CFStringGetCharacterAtIndex (string_ref, j - 1);
932 if (hb_in_range<UniChar> (ch, 0xD800u, 0xDBFFu))
933 /* This is the second of a surrogate pair. Don't need .notdef
934 * for this one. */
935 continue;
936 }
937 if (buffer->unicode->is_default_ignorable (ch))
938 continue;
939
940 info->codepoint = notdef;
941 info->cluster = log_clusters[j];
942
943 info->mask = advance;
944 info->var1.i32 = x_offset;
945 info->var2.i32 = y_offset;
946
947 info++;
948 buffer->len++;
949 }
950 if (HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
951 buffer->reverse_range (old_len, buffer->len);
952 advances_so_far += run_advance;
953 continue;
954 }
955 }
956
957 unsigned int num_glyphs = CTRunGetGlyphCount (run);
958 if (num_glyphs == 0)
959 continue;
960
961 if (!buffer->ensure_inplace (buffer->len + num_glyphs))
962 goto resize_and_retry;
963
964 hb_glyph_info_t *run_info = buffer->info + buffer->len;
965
966 /* Testing used to indicate that CTRunGetGlyphsPtr, etc (almost?) always
967 * succeed, and so copying data to our own buffer will be rare. Reports
968 * have it that this changed in OS X 10.10 Yosemite, and nullptr is returned
969 * frequently. At any rate, we can test that codepath by setting USE_PTR
970 * to false. */
971
972 #define USE_PTR true
973
974 #define SCRATCH_SAVE() \
975 unsigned int scratch_size_saved = scratch_size; \
976 hb_buffer_t::scratch_buffer_t *scratch_saved = scratch
977
978 #define SCRATCH_RESTORE() \
979 scratch_size = scratch_size_saved; \
980 scratch = scratch_saved;
981
982 { /* Setup glyphs */
983 SCRATCH_SAVE();
984 const CGGlyph* glyphs = USE_PTR ? CTRunGetGlyphsPtr (run) : nullptr;
985 if (!glyphs) {
986 ALLOCATE_ARRAY (CGGlyph, glyph_buf, num_glyphs, goto resize_and_retry);
987 CTRunGetGlyphs (run, range_all, glyph_buf);
988 glyphs = glyph_buf;
989 }
990 const CFIndex* string_indices = USE_PTR ? CTRunGetStringIndicesPtr (run) : nullptr;
991 if (!string_indices) {
992 ALLOCATE_ARRAY (CFIndex, index_buf, num_glyphs, goto resize_and_retry);
993 CTRunGetStringIndices (run, range_all, index_buf);
994 string_indices = index_buf;
995 }
996 hb_glyph_info_t *info = run_info;
997 for (unsigned int j = 0; j < num_glyphs; j++)
998 {
999 info->codepoint = glyphs[j];
1000 info->cluster = log_clusters[string_indices[j]];
1001 info++;
1002 }
1003 SCRATCH_RESTORE();
1004 }
1005 {
1006 /* Setup positions.
1007 * Note that CoreText does not return advances for glyphs. As such,
1008 * for all but last glyph, we use the delta position to next glyph as
1009 * advance (in the advance direction only), and for last glyph we set
1010 * whatever is needed to make the whole run's advance add up. */
1011 SCRATCH_SAVE();
1012 const CGPoint* positions = USE_PTR ? CTRunGetPositionsPtr (run) : nullptr;
1013 if (!positions) {
1014 ALLOCATE_ARRAY (CGPoint, position_buf, num_glyphs, goto resize_and_retry);
1015 CTRunGetPositions (run, range_all, position_buf);
1016 positions = position_buf;
1017 }
1018 hb_glyph_info_t *info = run_info;
1019 if (HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction))
1020 {
1021 hb_position_t x_offset = (positions[0].x - advances_so_far) * x_mult;
1022 for (unsigned int j = 0; j < num_glyphs; j++)
1023 {
1024 double advance;
1025 if (likely (j + 1 < num_glyphs))
1026 advance = positions[j + 1].x - positions[j].x;
1027 else /* last glyph */
1028 advance = run_advance - (positions[j].x - positions[0].x);
1029 info->mask = advance * x_mult;
1030 info->var1.i32 = x_offset;
1031 info->var2.i32 = positions[j].y * y_mult;
1032 info++;
1033 }
1034 }
1035 else
1036 {
1037 hb_position_t y_offset = (positions[0].y - advances_so_far) * y_mult;
1038 for (unsigned int j = 0; j < num_glyphs; j++)
1039 {
1040 double advance;
1041 if (likely (j + 1 < num_glyphs))
1042 advance = positions[j + 1].y - positions[j].y;
1043 else /* last glyph */
1044 advance = run_advance - (positions[j].y - positions[0].y);
1045 info->mask = advance * y_mult;
1046 info->var1.i32 = positions[j].x * x_mult;
1047 info->var2.i32 = y_offset;
1048 info++;
1049 }
1050 }
1051 SCRATCH_RESTORE();
1052 advances_so_far += run_advance;
1053 }
1054 #undef SCRATCH_RESTORE
1055 #undef SCRATCH_SAVE
1056 #undef USE_PTR
1057 #undef ALLOCATE_ARRAY
1058
1059 buffer->len += num_glyphs;
1060 }
1061
1062 /* Mac OS 10.6 doesn't have kCTTypesetterOptionForcedEmbeddingLevel,
1063 * or if it does, it doesn't respect it. So we get runs with wrong
1064 * directions. As such, disable the assert... It wouldn't crash, but
1065 * cursoring will be off...
1066 *
1067 * https://crbug.com/419769
1068 */
1069 if (false)
1070 {
1071 /* Make sure all runs had the expected direction. */
1072 bool backward = HB_DIRECTION_IS_BACKWARD (buffer->props.direction);
1073 assert (bool (status_and & kCTRunStatusRightToLeft) == backward);
1074 assert (bool (status_or & kCTRunStatusRightToLeft) == backward);
1075 }
1076
1077 buffer->clear_positions ();
1078
1079 unsigned int count = buffer->len;
1080 hb_glyph_info_t *info = buffer->info;
1081 hb_glyph_position_t *pos = buffer->pos;
1082 if (HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction))
1083 for (unsigned int i = 0; i < count; i++)
1084 {
1085 pos->x_advance = info->mask;
1086 pos->x_offset = info->var1.i32;
1087 pos->y_offset = info->var2.i32;
1088
1089 info++, pos++;
1090 }
1091 else
1092 for (unsigned int i = 0; i < count; i++)
1093 {
1094 pos->y_advance = info->mask;
1095 pos->x_offset = info->var1.i32;
1096 pos->y_offset = info->var2.i32;
1097
1098 info++, pos++;
1099 }
1100
1101 /* Fix up clusters so that we never return out-of-order indices;
1102 * if core text has reordered glyphs, we'll merge them to the
1103 * beginning of the reordered cluster. CoreText is nice enough
1104 * to tell us whenever it has produced nonmonotonic results...
1105 * Note that we assume the input clusters were nonmonotonic to
1106 * begin with.
1107 *
1108 * This does *not* mean we'll form the same clusters as Uniscribe
1109 * or the native OT backend, only that the cluster indices will be
1110 * monotonic in the output buffer. */
1111 if (count > 1 && (status_or & kCTRunStatusNonMonotonic))
1112 {
1113 hb_glyph_info_t *info = buffer->info;
1114 if (HB_DIRECTION_IS_FORWARD (buffer->props.direction))
1115 {
1116 unsigned int cluster = info[count - 1].cluster;
1117 for (unsigned int i = count - 1; i > 0; i--)
1118 {
1119 cluster = MIN (cluster, info[i - 1].cluster);
1120 info[i - 1].cluster = cluster;
1121 }
1122 }
1123 else
1124 {
1125 unsigned int cluster = info[0].cluster;
1126 for (unsigned int i = 1; i < count; i++)
1127 {
1128 cluster = MIN (cluster, info[i].cluster);
1129 info[i].cluster = cluster;
1130 }
1131 }
1132 }
1133 }
1134
1135 buffer->unsafe_to_break_all ();
1136
1137 #undef FAIL
1138
1139 fail:
1140 if (string_ref)
1141 CFRelease (string_ref);
1142 if (line)
1143 CFRelease (line);
1144
1145 for (unsigned int i = 0; i < range_records.length; i++)
1146 if (range_records[i].font)
1147 CFRelease (range_records[i].font);
1148
1149 return ret;
1150 }
1151
1152
1153 /*
1154 * AAT shaper
1155 */
1156
1157 /*
1158 * shaper face data
1159 */
1160
1161 struct hb_coretext_aat_face_data_t {};
1162
1163 hb_coretext_aat_face_data_t *
1164 _hb_coretext_aat_shaper_face_data_create (hb_face_t *face)
1165 {
1166 return hb_aat_layout_has_substitution (face) || hb_aat_layout_has_positioning (face) ?
1167 (hb_coretext_aat_face_data_t *) HB_SHAPER_DATA_SUCCEEDED : nullptr;
1168 }
1169
1170 void
1171 _hb_coretext_aat_shaper_face_data_destroy (hb_coretext_aat_face_data_t *data HB_UNUSED)
1172 {
1173 }
1174
1175
1176 /*
1177 * shaper font data
1178 */
1179
1180 struct hb_coretext_aat_font_data_t {};
1181
1182 hb_coretext_aat_font_data_t *
1183 _hb_coretext_aat_shaper_font_data_create (hb_font_t *font)
1184 {
1185 return font->data.coretext ? (hb_coretext_aat_font_data_t *) HB_SHAPER_DATA_SUCCEEDED : nullptr;
1186 }
1187
1188 void
1189 _hb_coretext_aat_shaper_font_data_destroy (hb_coretext_aat_font_data_t *data HB_UNUSED)
1190 {
1191 }
1192
1193
1194 /*
1195 * shaper
1196 */
1197
1198 hb_bool_t
1199 _hb_coretext_aat_shape (hb_shape_plan_t *shape_plan,
1200 hb_font_t *font,
1201 hb_buffer_t *buffer,
1202 const hb_feature_t *features,
1203 unsigned int num_features)
1204 {
1205 return _hb_coretext_shape (shape_plan, font, buffer, features, num_features);
1206 }