src/hb-coretext.cc

   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 #define HB_SHAPER coretext
  30 #include "hb-shaper-impl-private.hh"
  31
  32 #include "hb-coretext.h"
  33
  34
  35 #ifndef HB_DEBUG_CORETEXT
  36 #define HB_DEBUG_CORETEXT (HB_DEBUG+0)
  37 #endif
  38
  39
  40 static void
  41 release_table_data (void *user_data)
  42 {
  43   CFDataRef cf_data = reinterpret_cast<CFDataRef> (user_data);
  44   CFRelease(cf_data);
  45 }
  46
  47 static hb_blob_t *
  48 reference_table  (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data)
  49 {
  50   CGFontRef cg_font = reinterpret_cast<CGFontRef> (user_data);
  51   CFDataRef cf_data = CGFontCopyTableForTag (cg_font, tag);
  52   if (unlikely (!cf_data))
  53     return NULL;
  54
  55   const char *data = reinterpret_cast<const char*> (CFDataGetBytePtr (cf_data));
  56   const size_t length = CFDataGetLength (cf_data);
  57   if (!data || !length)
  58     return NULL;
  59
  60   return hb_blob_create (data, length, HB_MEMORY_MODE_READONLY,
  61                          reinterpret_cast<void *> (const_cast<__CFData *> (cf_data)),
  62                          release_table_data);
  63 }
  64
  65 hb_face_t *
  66 hb_coretext_face_create (CGFontRef cg_font)
  67 {
  68   return hb_face_create_for_tables (reference_table, CGFontRetain (cg_font), (hb_destroy_func_t) CGFontRelease);
  69 }
  70
  71
  72 HB_SHAPER_DATA_ENSURE_DECLARE(coretext, face)
  73 HB_SHAPER_DATA_ENSURE_DECLARE(coretext, font)
  74
  75
  76 /*
  77  * shaper face data
  78  */
  79
  80 static CTFontDescriptorRef
  81 get_last_resort_font_desc (void)
  82 {
  83   // TODO Handle allocation failures?
  84   CTFontDescriptorRef last_resort = CTFontDescriptorCreateWithNameAndSize (CFSTR("LastResort"), 0);
  85   CFArrayRef cascade_list = CFArrayCreate (kCFAllocatorDefault,
  86                                            (const void **) &last_resort,
  87                                            1,
  88                                            &kCFTypeArrayCallBacks);
  89   CFRelease (last_resort);
  90   CFDictionaryRef attributes = CFDictionaryCreate (kCFAllocatorDefault,
  91                                                    (const void **) &kCTFontCascadeListAttribute,
  92                                                    (const void **) &cascade_list,
  93                                                    1,
  94                                                    &kCFTypeDictionaryKeyCallBacks,
  95                                                    &kCFTypeDictionaryValueCallBacks);
  96   CFRelease (cascade_list);
  97
  98   CTFontDescriptorRef font_desc = CTFontDescriptorCreateWithAttributes (attributes);
  99   CFRelease (attributes);
 100   return font_desc;
 101 }
 102
 103 static void
 104 release_data (void *info, const void *data, size_t size)
 105 {
 106   assert (hb_blob_get_length ((hb_blob_t *) info) == size &&
 107           hb_blob_get_data ((hb_blob_t *) info, NULL) == data);
 108
 109   hb_blob_destroy ((hb_blob_t *) info);
 110 }
 111
 112 static CGFontRef
 113 create_cg_font (hb_face_t *face)
 114 {
 115   CGFontRef cg_font = NULL;
 116   if (face->destroy == (hb_destroy_func_t) CGFontRelease)
 117   {
 118     cg_font = CGFontRetain ((CGFontRef) face->user_data);
 119   }
 120   else
 121   {
 122     hb_blob_t *blob = hb_face_reference_blob (face);
 123     unsigned int blob_length;
 124     const char *blob_data = hb_blob_get_data (blob, &blob_length);
 125     if (unlikely (!blob_length))
 126       DEBUG_MSG (CORETEXT, face, "Face has empty blob");
 127
 128     CGDataProviderRef provider = CGDataProviderCreateWithData (blob, blob_data, blob_length, &release_data);
 129     if (likely (provider))
 130     {
 131       cg_font = CGFontCreateWithDataProvider (provider);
 132       if (unlikely (!cg_font))
 133         DEBUG_MSG (CORETEXT, face, "Face CGFontCreateWithDataProvider() failed");
 134       CGDataProviderRelease (provider);
 135     }
 136   }
 137   return cg_font;
 138 }
 139
 140 static CTFontRef
 141 create_ct_font (CGFontRef cg_font, CGFloat font_size)
 142 {
 143   CTFontRef ct_font = CTFontCreateWithGraphicsFont (cg_font, font_size, NULL, NULL);
 144   if (unlikely (!ct_font)) {
 145     DEBUG_MSG (CORETEXT, cg_font, "Font CTFontCreateWithGraphicsFont() failed");
 146     return NULL;
 147   }
 148   CFURLRef original_url = (CFURLRef)CTFontCopyAttribute(ct_font, kCTFontURLAttribute);
 149
 150   /* Create font copy with cascade list that has LastResort first; this speeds up CoreText
 151    * font fallback which we don't need anyway. */
 152   {
 153     CTFontDescriptorRef last_resort_font_desc = get_last_resort_font_desc ();
 154     CTFontRef new_ct_font = CTFontCreateCopyWithAttributes (ct_font, 0.0, NULL, last_resort_font_desc);
 155     CFRelease (last_resort_font_desc);
 156     if (new_ct_font)
 157     {
 158       /* The CTFontCreateCopyWithAttributes call fails to stay on the same font
 159        * when reconfiguring the cascade list and may switch to a different font
 160        * when there are fonts that go by the same name, since the descriptor is
 161        * just name and size.
 162        *
 163        * Avoid reconfiguring the cascade lists if the new font is outside the
 164        * system locations that we cannot access from the sandboxed renderer
 165        * process in Blink. This can be detected by the new file URL location
 166        * that the newly found font points to. */
 167       CFURLRef new_url = (CFURLRef) CTFontCopyAttribute (new_ct_font, kCTFontURLAttribute);
 168       // Keep reconfigured font if URL cannot be retrieved (seems to be the case
 169       // on Mac OS 10.12 Sierra), speculative fix for crbug.com/625606
 170       if (!original_url || !new_url || CFEqual (original_url, new_url)) {
 171         CFRelease (ct_font);
 172         ct_font = new_ct_font;
 173       } else {
 174         CFRelease (new_ct_font);
 175         DEBUG_MSG (CORETEXT, ct_font, "Discarding reconfigured CTFont, location changed.");
 176       }
 177       if (new_url)
 178         CFRelease (new_url);
 179     }
 180     else
 181       DEBUG_MSG (CORETEXT, ct_font, "Font copy with empty cascade list failed");
 182   }
 183
 184   if (original_url)
 185     CFRelease (original_url);
 186   return ct_font;
 187 }
 188
 189 struct hb_coretext_shaper_face_data_t {
 190   CGFontRef cg_font;
 191   CTFontRef ct_font;
 192 };
 193
 194 hb_coretext_shaper_face_data_t *
 195 _hb_coretext_shaper_face_data_create (hb_face_t *face)
 196 {
 197   hb_coretext_shaper_face_data_t *data = (hb_coretext_shaper_face_data_t *) calloc (1, sizeof (hb_coretext_shaper_face_data_t));
 198   if (unlikely (!data))
 199     return NULL;
 200
 201   data->cg_font = create_cg_font (face);
 202   if (unlikely (!data->cg_font))
 203   {
 204     DEBUG_MSG (CORETEXT, face, "CGFont creation failed..");
 205     free (data);
 206     return NULL;
 207   }
 208
 209   /* We use 36pt size instead of UPEM, because CoreText implements the 'trak' table,
 210    * which can make the font too tight at large sizes.  36pt should be a good semi-neutral
 211    * size.
 212    *
 213    * Since we always create CTFont at a fixed size, our CTFont lives in face_data
 214    * instead of font_data.  Which is good, because when people change scale on
 215    * hb_font_t, we won't need to update our CTFont. */
 216   data->ct_font = create_ct_font (data->cg_font, 36.);
 217   if (unlikely (!data->ct_font))
 218   {
 219     DEBUG_MSG (CORETEXT, face, "CTFont creation failed.");
 220     CFRelease (data->cg_font);
 221     free (data);
 222     return NULL;
 223   }
 224
 225   return data;
 226 }
 227
 228 void
 229 _hb_coretext_shaper_face_data_destroy (hb_coretext_shaper_face_data_t *data)
 230 {
 231   CFRelease (data->ct_font);
 232   CFRelease (data->cg_font);
 233   free (data);
 234 }
 235
 236 /*
 237  * Since: 0.9.10
 238  */
 239 CGFontRef
 240 hb_coretext_face_get_cg_font (hb_face_t *face)
 241 {
 242   if (unlikely (!hb_coretext_shaper_face_data_ensure (face))) return NULL;
 243   hb_coretext_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
 244   return face_data->cg_font;
 245 }
 246
 247
 248 /*
 249  * shaper font data
 250  */
 251
 252 struct hb_coretext_shaper_font_data_t {};
 253
 254 hb_coretext_shaper_font_data_t *
 255 _hb_coretext_shaper_font_data_create (hb_font_t *font HB_UNUSED)
 256 {
 257   return (hb_coretext_shaper_font_data_t *) HB_SHAPER_DATA_SUCCEEDED;
 258 }
 259
 260 void
 261 _hb_coretext_shaper_font_data_destroy (hb_coretext_shaper_font_data_t *data)
 262 {
 263 }
 264
 265
 266 /*
 267  * shaper shape_plan data
 268  */
 269
 270 struct hb_coretext_shaper_shape_plan_data_t {};
 271
 272 hb_coretext_shaper_shape_plan_data_t *
 273 _hb_coretext_shaper_shape_plan_data_create (hb_shape_plan_t    *shape_plan HB_UNUSED,
 274                                              const hb_feature_t *user_features HB_UNUSED,
 275                                              unsigned int        num_user_features HB_UNUSED)
 276 {
 277   return (hb_coretext_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
 278 }
 279
 280 void
 281 _hb_coretext_shaper_shape_plan_data_destroy (hb_coretext_shaper_shape_plan_data_t *data HB_UNUSED)
 282 {
 283 }
 284
 285 CTFontRef
 286 hb_coretext_font_get_ct_font (hb_font_t *font)
 287 {
 288   hb_face_t *face = font->face;
 289   if (unlikely (!hb_coretext_shaper_face_data_ensure (face))) return NULL;
 290   hb_coretext_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
 291   return face_data->ct_font;
 292 }
 293
 294
 295 /*
 296  * shaper
 297  */
 298
 299 struct feature_record_t {
 300   unsigned int feature;
 301   unsigned int setting;
 302 };
 303
 304 struct active_feature_t {
 305   feature_record_t rec;
 306   unsigned int order;
 307
 308   static int cmp (const active_feature_t *a, const active_feature_t *b) {
 309     return a->rec.feature < b->rec.feature ? -1 : a->rec.feature > b->rec.feature ? 1 :
 310            a->order < b->order ? -1 : a->order > b->order ? 1 :
 311            a->rec.setting < b->rec.setting ? -1 : a->rec.setting > b->rec.setting ? 1 :
 312            0;
 313   }
 314   bool operator== (const active_feature_t *f) {
 315     return cmp (this, f) == 0;
 316   }
 317 };
 318
 319 struct feature_event_t {
 320   unsigned int index;
 321   bool start;
 322   active_feature_t feature;
 323
 324   static int cmp (const feature_event_t *a, const feature_event_t *b) {
 325     return a->index < b->index ? -1 : a->index > b->index ? 1 :
 326            a->start < b->start ? -1 : a->start > b->start ? 1 :
 327            active_feature_t::cmp (&a->feature, &b->feature);
 328   }
 329 };
 330
 331 struct range_record_t {
 332   CTFontRef font;
 333   unsigned int index_first; /* == start */
 334   unsigned int index_last;  /* == end - 1 */
 335 };
 336
 337
 338 /* The following enum members are added in OS X 10.8. */
 339 #define kAltHalfWidthTextSelector               6
 340 #define kAltProportionalTextSelector            5
 341 #define kAlternateHorizKanaOffSelector          1
 342 #define kAlternateHorizKanaOnSelector           0
 343 #define kAlternateKanaType                      34
 344 #define kAlternateVertKanaOffSelector           3
 345 #define kAlternateVertKanaOnSelector            2
 346 #define kCaseSensitiveLayoutOffSelector         1
 347 #define kCaseSensitiveLayoutOnSelector          0
 348 #define kCaseSensitiveLayoutType                33
 349 #define kCaseSensitiveSpacingOffSelector        3
 350 #define kCaseSensitiveSpacingOnSelector         2
 351 #define kContextualAlternatesOffSelector        1
 352 #define kContextualAlternatesOnSelector         0
 353 #define kContextualAlternatesType               36
 354 #define kContextualLigaturesOffSelector         19
 355 #define kContextualLigaturesOnSelector          18
 356 #define kContextualSwashAlternatesOffSelector   5
 357 #define kContextualSwashAlternatesOnSelector    4
 358 #define kDefaultLowerCaseSelector               0
 359 #define kDefaultUpperCaseSelector               0
 360 #define kHistoricalLigaturesOffSelector         21
 361 #define kHistoricalLigaturesOnSelector          20
 362 #define kHojoCharactersSelector                 12
 363 #define kJIS2004CharactersSelector              11
 364 #define kLowerCasePetiteCapsSelector            2
 365 #define kLowerCaseSmallCapsSelector             1
 366 #define kLowerCaseType                          37
 367 #define kMathematicalGreekOffSelector           11
 368 #define kMathematicalGreekOnSelector            10
 369 #define kNLCCharactersSelector                  13
 370 #define kQuarterWidthTextSelector               4
 371 #define kScientificInferiorsSelector            4
 372 #define kStylisticAltEightOffSelector           17
 373 #define kStylisticAltEightOnSelector            16
 374 #define kStylisticAltEighteenOffSelector        37
 375 #define kStylisticAltEighteenOnSelector         36
 376 #define kStylisticAltElevenOffSelector          23
 377 #define kStylisticAltElevenOnSelector           22
 378 #define kStylisticAltFifteenOffSelector         31
 379 #define kStylisticAltFifteenOnSelector          30
 380 #define kStylisticAltFiveOffSelector            11
 381 #define kStylisticAltFiveOnSelector             10
 382 #define kStylisticAltFourOffSelector            9
 383 #define kStylisticAltFourOnSelector             8
 384 #define kStylisticAltFourteenOffSelector        29
 385 #define kStylisticAltFourteenOnSelector         28
 386 #define kStylisticAltNineOffSelector            19
 387 #define kStylisticAltNineOnSelector             18
 388 #define kStylisticAltNineteenOffSelector        39
 389 #define kStylisticAltNineteenOnSelector         38
 390 #define kStylisticAltOneOffSelector             3
 391 #define kStylisticAltOneOnSelector              2
 392 #define kStylisticAltSevenOffSelector           15
 393 #define kStylisticAltSevenOnSelector            14
 394 #define kStylisticAltSeventeenOffSelector       35
 395 #define kStylisticAltSeventeenOnSelector        34
 396 #define kStylisticAltSixOffSelector             13
 397 #define kStylisticAltSixOnSelector              12
 398 #define kStylisticAltSixteenOffSelector         33
 399 #define kStylisticAltSixteenOnSelector          32
 400 #define kStylisticAltTenOffSelector             21
 401 #define kStylisticAltTenOnSelector              20
 402 #define kStylisticAltThirteenOffSelector        27
 403 #define kStylisticAltThirteenOnSelector         26
 404 #define kStylisticAltThreeOffSelector           7
 405 #define kStylisticAltThreeOnSelector            6
 406 #define kStylisticAltTwelveOffSelector          25
 407 #define kStylisticAltTwelveOnSelector           24
 408 #define kStylisticAltTwentyOffSelector          41
 409 #define kStylisticAltTwentyOnSelector           40
 410 #define kStylisticAltTwoOffSelector             5
 411 #define kStylisticAltTwoOnSelector              4
 412 #define kStylisticAlternativesType              35
 413 #define kSwashAlternatesOffSelector             3
 414 #define kSwashAlternatesOnSelector              2
 415 #define kThirdWidthTextSelector                 3
 416 #define kTraditionalNamesCharactersSelector     14
 417 #define kUpperCasePetiteCapsSelector            2
 418 #define kUpperCaseSmallCapsSelector             1
 419 #define kUpperCaseType                          38
 420
 421 /* Table data courtesy of Apple. */
 422 static const struct feature_mapping_t {
 423     FourCharCode otFeatureTag;
 424     uint16_t aatFeatureType;
 425     uint16_t selectorToEnable;
 426     uint16_t selectorToDisable;
 427 } feature_mappings[] = {
 428     { 'c2pc',   kUpperCaseType,             kUpperCasePetiteCapsSelector,           kDefaultUpperCaseSelector },
 429     { 'c2sc',   kUpperCaseType,             kUpperCaseSmallCapsSelector,            kDefaultUpperCaseSelector },
 430     { 'calt',   kContextualAlternatesType,  kContextualAlternatesOnSelector,        kContextualAlternatesOffSelector },
 431     { 'case',   kCaseSensitiveLayoutType,   kCaseSensitiveLayoutOnSelector,         kCaseSensitiveLayoutOffSelector },
 432     { 'clig',   kLigaturesType,             kContextualLigaturesOnSelector,         kContextualLigaturesOffSelector },
 433     { 'cpsp',   kCaseSensitiveLayoutType,   kCaseSensitiveSpacingOnSelector,        kCaseSensitiveSpacingOffSelector },
 434     { 'cswh',   kContextualAlternatesType,  kContextualSwashAlternatesOnSelector,   kContextualSwashAlternatesOffSelector },
 435     { 'dlig',   kLigaturesType,             kRareLigaturesOnSelector,               kRareLigaturesOffSelector },
 436     { 'expt',   kCharacterShapeType,        kExpertCharactersSelector,              16 },
 437     { 'frac',   kFractionsType,             kDiagonalFractionsSelector,             kNoFractionsSelector },
 438     { 'fwid',   kTextSpacingType,           kMonospacedTextSelector,                7 },
 439     { 'halt',   kTextSpacingType,           kAltHalfWidthTextSelector,              7 },
 440     { 'hist',   kLigaturesType,             kHistoricalLigaturesOnSelector,         kHistoricalLigaturesOffSelector },
 441     { 'hkna',   kAlternateKanaType,         kAlternateHorizKanaOnSelector,          kAlternateHorizKanaOffSelector, },
 442     { 'hlig',   kLigaturesType,             kHistoricalLigaturesOnSelector,         kHistoricalLigaturesOffSelector },
 443     { 'hngl',   kTransliterationType,       kHanjaToHangulSelector,                 kNoTransliterationSelector },
 444     { 'hojo',   kCharacterShapeType,        kHojoCharactersSelector,                16 },
 445     { 'hwid',   kTextSpacingType,           kHalfWidthTextSelector,                 7 },
 446     { 'ital',   kItalicCJKRomanType,        kCJKItalicRomanOnSelector,              kCJKItalicRomanOffSelector },
 447     { 'jp04',   kCharacterShapeType,        kJIS2004CharactersSelector,             16 },
 448     { 'jp78',   kCharacterShapeType,        kJIS1978CharactersSelector,             16 },
 449     { 'jp83',   kCharacterShapeType,        kJIS1983CharactersSelector,             16 },
 450     { 'jp90',   kCharacterShapeType,        kJIS1990CharactersSelector,             16 },
 451     { 'liga',   kLigaturesType,             kCommonLigaturesOnSelector,             kCommonLigaturesOffSelector },
 452     { 'lnum',   kNumberCaseType,            kUpperCaseNumbersSelector,              2 },
 453     { 'mgrk',   kMathematicalExtrasType,    kMathematicalGreekOnSelector,           kMathematicalGreekOffSelector },
 454     { 'nlck',   kCharacterShapeType,        kNLCCharactersSelector,                 16 },
 455     { 'onum',   kNumberCaseType,            kLowerCaseNumbersSelector,              2 },
 456     { 'ordn',   kVerticalPositionType,      kOrdinalsSelector,                      kNormalPositionSelector },
 457     { 'palt',   kTextSpacingType,           kAltProportionalTextSelector,           7 },
 458     { 'pcap',   kLowerCaseType,             kLowerCasePetiteCapsSelector,           kDefaultLowerCaseSelector },
 459     { 'pkna',   kTextSpacingType,           kProportionalTextSelector,              7 },
 460     { 'pnum',   kNumberSpacingType,         kProportionalNumbersSelector,           4 },
 461     { 'pwid',   kTextSpacingType,           kProportionalTextSelector,              7 },
 462     { 'qwid',   kTextSpacingType,           kQuarterWidthTextSelector,              7 },
 463     { 'ruby',   kRubyKanaType,              kRubyKanaOnSelector,                    kRubyKanaOffSelector },
 464     { 'sinf',   kVerticalPositionType,      kScientificInferiorsSelector,           kNormalPositionSelector },
 465     { 'smcp',   kLowerCaseType,             kLowerCaseSmallCapsSelector,            kDefaultLowerCaseSelector },
 466     { 'smpl',   kCharacterShapeType,        kSimplifiedCharactersSelector,          16 },
 467     { 'ss01',   kStylisticAlternativesType, kStylisticAltOneOnSelector,             kStylisticAltOneOffSelector },
 468     { 'ss02',   kStylisticAlternativesType, kStylisticAltTwoOnSelector,             kStylisticAltTwoOffSelector },
 469     { 'ss03',   kStylisticAlternativesType, kStylisticAltThreeOnSelector,           kStylisticAltThreeOffSelector },
 470     { 'ss04',   kStylisticAlternativesType, kStylisticAltFourOnSelector,            kStylisticAltFourOffSelector },
 471     { 'ss05',   kStylisticAlternativesType, kStylisticAltFiveOnSelector,            kStylisticAltFiveOffSelector },
 472     { 'ss06',   kStylisticAlternativesType, kStylisticAltSixOnSelector,             kStylisticAltSixOffSelector },
 473     { 'ss07',   kStylisticAlternativesType, kStylisticAltSevenOnSelector,           kStylisticAltSevenOffSelector },
 474     { 'ss08',   kStylisticAlternativesType, kStylisticAltEightOnSelector,           kStylisticAltEightOffSelector },
 475     { 'ss09',   kStylisticAlternativesType, kStylisticAltNineOnSelector,            kStylisticAltNineOffSelector },
 476     { 'ss10',   kStylisticAlternativesType, kStylisticAltTenOnSelector,             kStylisticAltTenOffSelector },
 477     { 'ss11',   kStylisticAlternativesType, kStylisticAltElevenOnSelector,          kStylisticAltElevenOffSelector },
 478     { 'ss12',   kStylisticAlternativesType, kStylisticAltTwelveOnSelector,          kStylisticAltTwelveOffSelector },
 479     { 'ss13',   kStylisticAlternativesType, kStylisticAltThirteenOnSelector,        kStylisticAltThirteenOffSelector },
 480     { 'ss14',   kStylisticAlternativesType, kStylisticAltFourteenOnSelector,        kStylisticAltFourteenOffSelector },
 481     { 'ss15',   kStylisticAlternativesType, kStylisticAltFifteenOnSelector,         kStylisticAltFifteenOffSelector },
 482     { 'ss16',   kStylisticAlternativesType, kStylisticAltSixteenOnSelector,         kStylisticAltSixteenOffSelector },
 483     { 'ss17',   kStylisticAlternativesType, kStylisticAltSeventeenOnSelector,       kStylisticAltSeventeenOffSelector },
 484     { 'ss18',   kStylisticAlternativesType, kStylisticAltEighteenOnSelector,        kStylisticAltEighteenOffSelector },
 485     { 'ss19',   kStylisticAlternativesType, kStylisticAltNineteenOnSelector,        kStylisticAltNineteenOffSelector },
 486     { 'ss20',   kStylisticAlternativesType, kStylisticAltTwentyOnSelector,          kStylisticAltTwentyOffSelector },
 487     { 'subs',   kVerticalPositionType,      kInferiorsSelector,                     kNormalPositionSelector },
 488     { 'sups',   kVerticalPositionType,      kSuperiorsSelector,                     kNormalPositionSelector },
 489     { 'swsh',   kContextualAlternatesType,  kSwashAlternatesOnSelector,             kSwashAlternatesOffSelector },
 490     { 'titl',   kStyleOptionsType,          kTitlingCapsSelector,                   kNoStyleOptionsSelector },
 491     { 'tnam',   kCharacterShapeType,        kTraditionalNamesCharactersSelector,    16 },
 492     { 'tnum',   kNumberSpacingType,         kMonospacedNumbersSelector,             4 },
 493     { 'trad',   kCharacterShapeType,        kTraditionalCharactersSelector,         16 },
 494     { 'twid',   kTextSpacingType,           kThirdWidthTextSelector,                7 },
 495     { 'unic',   kLetterCaseType,            14,                                     15 },
 496     { 'valt',   kTextSpacingType,           kAltProportionalTextSelector,           7 },
 497     { 'vert',   kVerticalSubstitutionType,  kSubstituteVerticalFormsOnSelector,     kSubstituteVerticalFormsOffSelector },
 498     { 'vhal',   kTextSpacingType,           kAltHalfWidthTextSelector,              7 },
 499     { 'vkna',   kAlternateKanaType,         kAlternateVertKanaOnSelector,           kAlternateVertKanaOffSelector },
 500     { 'vpal',   kTextSpacingType,           kAltProportionalTextSelector,           7 },
 501     { 'vrt2',   kVerticalSubstitutionType,  kSubstituteVerticalFormsOnSelector,     kSubstituteVerticalFormsOffSelector },
 502     { 'zero',   kTypographicExtrasType,     kSlashedZeroOnSelector,                 kSlashedZeroOffSelector },
 503 };
 504
 505 static int
 506 _hb_feature_mapping_cmp (const void *key_, const void *entry_)
 507 {
 508   unsigned int key = * (unsigned int *) key_;
 509   const feature_mapping_t * entry = (const feature_mapping_t *) entry_;
 510   return key < entry->otFeatureTag ? -1 :
 511          key > entry->otFeatureTag ? 1 :
 512          0;
 513 }
 514
 515 hb_bool_t
 516 _hb_coretext_shape (hb_shape_plan_t    *shape_plan,
 517                     hb_font_t          *font,
 518                     hb_buffer_t        *buffer,
 519                     const hb_feature_t *features,
 520                     unsigned int        num_features)
 521 {
 522   hb_face_t *face = font->face;
 523   hb_coretext_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
 524
 525   CGFloat ct_font_size = CTFontGetSize (face_data->ct_font);
 526   CGFloat x_mult = (CGFloat) font->x_scale / ct_font_size;
 527   CGFloat y_mult = (CGFloat) font->y_scale / ct_font_size;
 528
 529   /* Attach marks to their bases, to match the 'ot' shaper.
 530    * Adapted from hb-ot-shape:hb_form_clusters().
 531    * Note that this only makes us be closer to the 'ot' shaper,
 532    * but by no means the same.  For example, if there's
 533    * B1 M1 B2 M2, and B1-B2 form a ligature, M2's cluster will
 534    * continue pointing to B2 even though B2 was merged into B1's
 535    * cluster... */
 536   if (buffer->cluster_level == HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES)
 537   {
 538     hb_unicode_funcs_t *unicode = buffer->unicode;
 539     unsigned int count = buffer->len;
 540     hb_glyph_info_t *info = buffer->info;
 541     for (unsigned int i = 1; i < count; i++)
 542       if (HB_UNICODE_GENERAL_CATEGORY_IS_MARK (unicode->general_category (info[i].codepoint)))
 543         buffer->merge_clusters (i - 1, i + 1);
 544   }
 545
 546   hb_auto_array_t<feature_record_t> feature_records;
 547   hb_auto_array_t<range_record_t> range_records;
 548
 549   /*
 550    * Set up features.
 551    * (copied + modified from code from hb-uniscribe.cc)
 552    */
 553   if (num_features)
 554   {
 555     /* Sort features by start/end events. */
 556     hb_auto_array_t<feature_event_t> feature_events;
 557     for (unsigned int i = 0; i < num_features; i++)
 558     {
 559       const feature_mapping_t * mapping = (const feature_mapping_t *) bsearch (&features[i].tag,
 560                                                                                feature_mappings,
 561                                                                                ARRAY_LENGTH (feature_mappings),
 562                                                                                sizeof (feature_mappings[0]),
 563                                                                                _hb_feature_mapping_cmp);
 564       if (!mapping)
 565         continue;
 566
 567       active_feature_t feature;
 568       feature.rec.feature = mapping->aatFeatureType;
 569       feature.rec.setting = features[i].value ? mapping->selectorToEnable : mapping->selectorToDisable;
 570       feature.order = i;
 571
 572       feature_event_t *event;
 573
 574       event = feature_events.push ();
 575       if (unlikely (!event))
 576         goto fail_features;
 577       event->index = features[i].start;
 578       event->start = true;
 579       event->feature = feature;
 580
 581       event = feature_events.push ();
 582       if (unlikely (!event))
 583         goto fail_features;
 584       event->index = features[i].end;
 585       event->start = false;
 586       event->feature = feature;
 587     }
 588     feature_events.qsort ();
 589     /* Add a strategic final event. */
 590     {
 591       active_feature_t feature;
 592       feature.rec.feature = HB_TAG_NONE;
 593       feature.rec.setting = 0;
 594       feature.order = num_features + 1;
 595
 596       feature_event_t *event = feature_events.push ();
 597       if (unlikely (!event))
 598         goto fail_features;
 599       event->index = 0; /* This value does magic. */
 600       event->start = false;
 601       event->feature = feature;
 602     }
 603
 604     /* Scan events and save features for each range. */
 605     hb_auto_array_t<active_feature_t> active_features;
 606     unsigned int last_index = 0;
 607     for (unsigned int i = 0; i < feature_events.len; i++)
 608     {
 609       feature_event_t *event = &feature_events[i];
 610
 611       if (event->index != last_index)
 612       {
 613         /* Save a snapshot of active features and the range. */
 614         range_record_t *range = range_records.push ();
 615         if (unlikely (!range))
 616           goto fail_features;
 617
 618         if (active_features.len)
 619         {
 620           CFMutableArrayRef features_array = CFArrayCreateMutable(kCFAllocatorDefault, 0, &kCFTypeArrayCallBacks);
 621
 622           /* TODO sort and resolve conflicting features? */
 623           /* active_features.qsort (); */
 624           for (unsigned int j = 0; j < active_features.len; j++)
 625           {
 626             CFStringRef keys[2] = {
 627               kCTFontFeatureTypeIdentifierKey,
 628               kCTFontFeatureSelectorIdentifierKey
 629             };
 630             CFNumberRef values[2] = {
 631               CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &active_features[j].rec.feature),
 632               CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &active_features[j].rec.setting)
 633             };
 634             CFDictionaryRef dict = CFDictionaryCreate (kCFAllocatorDefault,
 635                                                        (const void **) keys,
 636                                                        (const void **) values,
 637                                                        2,
 638                                                        &kCFTypeDictionaryKeyCallBacks,
 639                                                        &kCFTypeDictionaryValueCallBacks);
 640             CFRelease (values[0]);
 641             CFRelease (values[1]);
 642
 643             CFArrayAppendValue (features_array, dict);
 644             CFRelease (dict);
 645
 646           }
 647
 648           CFDictionaryRef attributes = CFDictionaryCreate (kCFAllocatorDefault,
 649                                                            (const void **) &kCTFontFeatureSettingsAttribute,
 650                                                            (const void **) &features_array,
 651                                                            1,
 652                                                            &kCFTypeDictionaryKeyCallBacks,
 653                                                            &kCFTypeDictionaryValueCallBacks);
 654           CFRelease (features_array);
 655
 656           CTFontDescriptorRef font_desc = CTFontDescriptorCreateWithAttributes (attributes);
 657           CFRelease (attributes);
 658
 659           range->font = CTFontCreateCopyWithAttributes (face_data->ct_font, 0.0, NULL, font_desc);
 660           CFRelease (font_desc);
 661         }
 662         else
 663         {
 664           range->font = NULL;
 665         }
 666
 667         range->index_first = last_index;
 668         range->index_last  = event->index - 1;
 669
 670         last_index = event->index;
 671       }
 672
 673       if (event->start) {
 674         active_feature_t *feature = active_features.push ();
 675         if (unlikely (!feature))
 676           goto fail_features;
 677         *feature = event->feature;
 678       } else {
 679         active_feature_t *feature = active_features.find (&event->feature);
 680         if (feature)
 681           active_features.remove (feature - active_features.array);
 682       }
 683     }
 684
 685     if (!range_records.len) /* No active feature found. */
 686       goto fail_features;
 687   }
 688   else
 689   {
 690   fail_features:
 691     num_features = 0;
 692   }
 693
 694   unsigned int scratch_size;
 695   hb_buffer_t::scratch_buffer_t *scratch = buffer->get_scratch_buffer (&scratch_size);
 696
 697 #define ALLOCATE_ARRAY(Type, name, len, on_no_room) \
 698   Type *name = (Type *) scratch; \
 699   { \
 700     unsigned int _consumed = DIV_CEIL ((len) * sizeof (Type), sizeof (*scratch)); \
 701     if (unlikely (_consumed > scratch_size)) \
 702     { \
 703       on_no_room; \
 704       assert (0); \
 705     } \
 706     scratch += _consumed; \
 707     scratch_size -= _consumed; \
 708   }
 709
 710   ALLOCATE_ARRAY (UniChar, pchars, buffer->len * 2, /*nothing*/);
 711   unsigned int chars_len = 0;
 712   for (unsigned int i = 0; i < buffer->len; i++) {
 713     hb_codepoint_t c = buffer->info[i].codepoint;
 714     if (likely (c <= 0xFFFFu))
 715       pchars[chars_len++] = c;
 716     else if (unlikely (c > 0x10FFFFu))
 717       pchars[chars_len++] = 0xFFFDu;
 718     else {
 719       pchars[chars_len++] = 0xD800u + ((c - 0x10000u) >> 10);
 720       pchars[chars_len++] = 0xDC00u + ((c - 0x10000u) & ((1 << 10) - 1));
 721     }
 722   }
 723
 724   ALLOCATE_ARRAY (unsigned int, log_clusters, chars_len, /*nothing*/);
 725   chars_len = 0;
 726   for (unsigned int i = 0; i < buffer->len; i++)
 727   {
 728     hb_codepoint_t c = buffer->info[i].codepoint;
 729     unsigned int cluster = buffer->info[i].cluster;
 730     log_clusters[chars_len++] = cluster;
 731     if (hb_in_range (c, 0x10000u, 0x10FFFFu))
 732       log_clusters[chars_len++] = cluster; /* Surrogates. */
 733   }
 734
 735 #define FAIL(...) \
 736   HB_STMT_START { \
 737     DEBUG_MSG (CORETEXT, NULL, __VA_ARGS__); \
 738     ret = false; \
 739     goto fail; \
 740   } HB_STMT_END;
 741
 742   bool ret = true;
 743   CFStringRef string_ref = NULL;
 744   CTLineRef line = NULL;
 745
 746   if (0)
 747   {
 748 resize_and_retry:
 749     DEBUG_MSG (CORETEXT, buffer, "Buffer resize");
 750     /* string_ref uses the scratch-buffer for backing store, and line references
 751      * string_ref (via attr_string).  We must release those before resizing buffer. */
 752     assert (string_ref);
 753     assert (line);
 754     CFRelease (string_ref);
 755     CFRelease (line);
 756     string_ref = NULL;
 757     line = NULL;
 758
 759     /* Get previous start-of-scratch-area, that we use later for readjusting
 760      * our existing scratch arrays. */
 761     unsigned int old_scratch_used;
 762     hb_buffer_t::scratch_buffer_t *old_scratch;
 763     old_scratch = buffer->get_scratch_buffer (&old_scratch_used);
 764     old_scratch_used = scratch - old_scratch;
 765
 766     if (unlikely (!buffer->ensure (buffer->allocated * 2)))
 767       FAIL ("Buffer resize failed");
 768
 769     /* Adjust scratch, pchars, and log_cluster arrays.  This is ugly, but really the
 770      * cleanest way to do without completely restructuring the rest of this shaper. */
 771     scratch = buffer->get_scratch_buffer (&scratch_size);
 772     pchars = reinterpret_cast<UniChar *> (((char *) scratch + ((char *) pchars - (char *) old_scratch)));
 773     log_clusters = reinterpret_cast<unsigned int *> (((char *) scratch + ((char *) log_clusters - (char *) old_scratch)));
 774     scratch += old_scratch_used;
 775     scratch_size -= old_scratch_used;
 776   }
 777   {
 778     string_ref = CFStringCreateWithCharactersNoCopy (NULL,
 779                                                      pchars, chars_len,
 780                                                      kCFAllocatorNull);
 781     if (unlikely (!string_ref))
 782       FAIL ("CFStringCreateWithCharactersNoCopy failed");
 783
 784     /* Create an attributed string, populate it, and create a line from it, then release attributed string. */
 785     {
 786       CFMutableAttributedStringRef attr_string = CFAttributedStringCreateMutable (kCFAllocatorDefault,
 787                                                                                   chars_len);
 788       if (unlikely (!attr_string))
 789         FAIL ("CFAttributedStringCreateMutable failed");
 790       CFAttributedStringReplaceString (attr_string, CFRangeMake (0, 0), string_ref);
 791       if (HB_DIRECTION_IS_VERTICAL (buffer->props.direction))
 792       {
 793         CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
 794                                         kCTVerticalFormsAttributeName, kCFBooleanTrue);
 795       }
 796
 797       if (buffer->props.language)
 798       {
 799 /* What's the iOS equivalent of this check?
 800  * The symbols was introduced in iOS 7.0.
 801  * At any rate, our fallback is safe and works fine. */
 802 #if MAC_OS_X_VERSION_MIN_REQUIRED < 1090
 803 #  define kCTLanguageAttributeName CFSTR ("NSLanguage")
 804 #endif
 805         CFStringRef lang = CFStringCreateWithCStringNoCopy (kCFAllocatorDefault,
 806                                                             hb_language_to_string (buffer->props.language),
 807                                                             kCFStringEncodingUTF8,
 808                                                             kCFAllocatorNull);
 809         if (unlikely (!lang))
 810           FAIL ("CFStringCreateWithCStringNoCopy failed");
 811         CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
 812                                         kCTLanguageAttributeName, lang);
 813         CFRelease (lang);
 814       }
 815       CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
 816                                       kCTFontAttributeName, face_data->ct_font);
 817
 818       if (num_features)
 819       {
 820         unsigned int start = 0;
 821         range_record_t *last_range = &range_records[0];
 822         for (unsigned int k = 0; k < chars_len; k++)
 823         {
 824           range_record_t *range = last_range;
 825           while (log_clusters[k] < range->index_first)
 826             range--;
 827           while (log_clusters[k] > range->index_last)
 828             range++;
 829           if (range != last_range)
 830           {
 831             if (last_range->font)
 832               CFAttributedStringSetAttribute (attr_string, CFRangeMake (start, k - start),
 833                                               kCTFontAttributeName, last_range->font);
 834
 835             start = k;
 836           }
 837
 838           last_range = range;
 839         }
 840         if (start != chars_len && last_range->font)
 841           CFAttributedStringSetAttribute (attr_string, CFRangeMake (start, chars_len - start),
 842                                           kCTFontAttributeName, last_range->font);
 843       }
 844
 845       int level = HB_DIRECTION_IS_FORWARD (buffer->props.direction) ? 0 : 1;
 846       CFNumberRef level_number = CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &level);
 847       CFDictionaryRef options = CFDictionaryCreate (kCFAllocatorDefault,
 848                                                     (const void **) &kCTTypesetterOptionForcedEmbeddingLevel,
 849                                                     (const void **) &level_number,
 850                                                     1,
 851                                                     &kCFTypeDictionaryKeyCallBacks,
 852                                                     &kCFTypeDictionaryValueCallBacks);
 853       if (unlikely (!options))
 854         FAIL ("CFDictionaryCreate failed");
 855
 856       CTTypesetterRef typesetter = CTTypesetterCreateWithAttributedStringAndOptions (attr_string, options);
 857       CFRelease (options);
 858       CFRelease (attr_string);
 859       if (unlikely (!typesetter))
 860         FAIL ("CTTypesetterCreateWithAttributedStringAndOptions failed");
 861
 862       line = CTTypesetterCreateLine (typesetter, CFRangeMake(0, 0));
 863       CFRelease (typesetter);
 864       if (unlikely (!line))
 865         FAIL ("CTTypesetterCreateLine failed");
 866     }
 867
 868     CFArrayRef glyph_runs = CTLineGetGlyphRuns (line);
 869     unsigned int num_runs = CFArrayGetCount (glyph_runs);
 870     DEBUG_MSG (CORETEXT, NULL, "Num runs: %d", num_runs);
 871
 872     buffer->len = 0;
 873     uint32_t status_and = ~0, status_or = 0;
 874     double advances_so_far = 0;
 875     /* For right-to-left runs, CoreText returns the glyphs positioned such that
 876      * any trailing whitespace is to the left of (0,0).  Adjust coordinate system
 877      * to fix for that.  Test with any RTL string with trailing spaces.
 878      * https://code.google.com/p/chromium/issues/detail?id=469028
 879      */
 880     if (HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
 881     {
 882       advances_so_far -= CTLineGetTrailingWhitespaceWidth (line);
 883       if (HB_DIRECTION_IS_VERTICAL (buffer->props.direction))
 884           advances_so_far = -advances_so_far;
 885     }
 886
 887     const CFRange range_all = CFRangeMake (0, 0);
 888
 889     for (unsigned int i = 0; i < num_runs; i++)
 890     {
 891       CTRunRef run = static_cast<CTRunRef>(CFArrayGetValueAtIndex (glyph_runs, i));
 892       CTRunStatus run_status = CTRunGetStatus (run);
 893       status_or  |= run_status;
 894       status_and &= run_status;
 895       DEBUG_MSG (CORETEXT, run, "CTRunStatus: %x", run_status);
 896       double run_advance = CTRunGetTypographicBounds (run, range_all, NULL, NULL, NULL);
 897       if (HB_DIRECTION_IS_VERTICAL (buffer->props.direction))
 898           run_advance = -run_advance;
 899       DEBUG_MSG (CORETEXT, run, "Run advance: %g", run_advance);
 900
 901       /* CoreText does automatic font fallback (AKA "cascading") for  characters
 902        * not supported by the requested font, and provides no way to turn it off,
 903        * so we must detect if the returned run uses a font other than the requested
 904        * one and fill in the buffer with .notdef glyphs instead of random glyph
 905        * indices from a different font.
 906        */
 907       CFDictionaryRef attributes = CTRunGetAttributes (run);
 908       CTFontRef run_ct_font = static_cast<CTFontRef>(CFDictionaryGetValue (attributes, kCTFontAttributeName));
 909       if (!CFEqual (run_ct_font, face_data->ct_font))
 910       {
 911         /* The run doesn't use our main font instance.  We have to figure out
 912          * whether font fallback happened, or this is just CoreText giving us
 913          * another CTFont using the same underlying CGFont.  CoreText seems
 914          * to do that in a variety of situations, one of which being vertical
 915          * text, but also perhaps for caching reasons.
 916          *
 917          * First, see if it uses any of our subfonts created to set font features...
 918          *
 919          * Next, compare the CGFont to the one we used to create our fonts.
 920          * Even this doesn't work all the time.
 921          *
 922          * Finally, we compare PS names, which I don't think are unique...
 923          *
 924          * Looks like if we really want to be sure here we have to modify the
 925          * font to change the name table, similar to what we do in the uniscribe
 926          * backend.
 927          *
 928          * However, even that wouldn't work if we were passed in the CGFont to
 929          * construct a hb_face to begin with.
 930          *
 931          * See: http://github.com/behdad/harfbuzz/pull/36
 932          *
 933          * Also see: https://bugs.chromium.org/p/chromium/issues/detail?id=597098
 934          */
 935         bool matched = false;
 936         for (unsigned int i = 0; i < range_records.len; i++)
 937           if (range_records[i].font && CFEqual (run_ct_font, range_records[i].font))
 938           {
 939             matched = true;
 940             break;
 941           }
 942         if (!matched)
 943         {
 944           CGFontRef run_cg_font = CTFontCopyGraphicsFont (run_ct_font, 0);
 945           if (run_cg_font)
 946           {
 947             matched = CFEqual (run_cg_font, face_data->cg_font);
 948             CFRelease (run_cg_font);
 949           }
 950         }
 951         if (!matched)
 952         {
 953           CFStringRef font_ps_name = CTFontCopyName (face_data->ct_font, kCTFontPostScriptNameKey);
 954           CFStringRef run_ps_name = CTFontCopyName (run_ct_font, kCTFontPostScriptNameKey);
 955           CFComparisonResult result = CFStringCompare (run_ps_name, font_ps_name, 0);
 956           CFRelease (run_ps_name);
 957           CFRelease (font_ps_name);
 958           if (result == kCFCompareEqualTo)
 959             matched = true;
 960         }
 961         if (!matched)
 962         {
 963           CFRange range = CTRunGetStringRange (run);
 964           DEBUG_MSG (CORETEXT, run, "Run used fallback font: %ld..%ld",
 965                      range.location, range.location + range.length);
 966           if (!buffer->ensure_inplace (buffer->len + range.length))
 967             goto resize_and_retry;
 968           hb_glyph_info_t *info = buffer->info + buffer->len;
 969
 970           hb_codepoint_t notdef = 0;
 971           hb_direction_t dir = buffer->props.direction;
 972           hb_position_t x_advance, y_advance, x_offset, y_offset;
 973           hb_font_get_glyph_advance_for_direction (font, notdef, dir, &x_advance, &y_advance);
 974           hb_font_get_glyph_origin_for_direction (font, notdef, dir, &x_offset, &y_offset);
 975           hb_position_t advance = x_advance + y_advance;
 976           x_offset = -x_offset;
 977           y_offset = -y_offset;
 978
 979           unsigned int old_len = buffer->len;
 980           for (CFIndex j = range.location; j < range.location + range.length; j++)
 981           {
 982               UniChar ch = CFStringGetCharacterAtIndex (string_ref, j);
 983               if (hb_in_range<UniChar> (ch, 0xDC00u, 0xDFFFu) && range.location < j)
 984               {
 985                 ch = CFStringGetCharacterAtIndex (string_ref, j - 1);
 986                 if (hb_in_range<UniChar> (ch, 0xD800u, 0xDBFFu))
 987                   /* This is the second of a surrogate pair.  Don't need .notdef
 988                    * for this one. */
 989                   continue;
 990               }
 991               if (buffer->unicode->is_default_ignorable (ch))
 992                 continue;
 993
 994               info->codepoint = notdef;
 995               info->cluster = log_clusters[j];
 996
 997               info->mask = advance;
 998               info->var1.i32 = x_offset;
 999               info->var2.i32 = y_offset;
1000
1001               info++;
1002               buffer->len++;
1003           }
1004           if (HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
1005             buffer->reverse_range (old_len, buffer->len);
1006           advances_so_far += run_advance;
1007           continue;
1008         }
1009       }
1010
1011       unsigned int num_glyphs = CTRunGetGlyphCount (run);
1012       if (num_glyphs == 0)
1013         continue;
1014
1015       if (!buffer->ensure_inplace (buffer->len + num_glyphs))
1016         goto resize_and_retry;
1017
1018       hb_glyph_info_t *run_info = buffer->info + buffer->len;
1019
1020       /* Testing used to indicate that CTRunGetGlyphsPtr, etc (almost?) always
1021        * succeed, and so copying data to our own buffer will be rare.  Reports
1022        * have it that this changed in OS X 10.10 Yosemite, and NULL is returned
1023        * frequently.  At any rate, we can test that codepath by setting USE_PTR
1024        * to false. */
1025
1026 #define USE_PTR true
1027
1028 #define SCRATCH_SAVE() \
1029   unsigned int scratch_size_saved = scratch_size; \
1030   hb_buffer_t::scratch_buffer_t *scratch_saved = scratch
1031
1032 #define SCRATCH_RESTORE() \
1033   scratch_size = scratch_size_saved; \
1034   scratch = scratch_saved;
1035
1036       { /* Setup glyphs */
1037         SCRATCH_SAVE();
1038         const CGGlyph* glyphs = USE_PTR ? CTRunGetGlyphsPtr (run) : NULL;
1039         if (!glyphs) {
1040           ALLOCATE_ARRAY (CGGlyph, glyph_buf, num_glyphs, goto resize_and_retry);
1041           CTRunGetGlyphs (run, range_all, glyph_buf);
1042           glyphs = glyph_buf;
1043         }
1044         const CFIndex* string_indices = USE_PTR ? CTRunGetStringIndicesPtr (run) : NULL;
1045         if (!string_indices) {
1046           ALLOCATE_ARRAY (CFIndex, index_buf, num_glyphs, goto resize_and_retry);
1047           CTRunGetStringIndices (run, range_all, index_buf);
1048           string_indices = index_buf;
1049         }
1050         hb_glyph_info_t *info = run_info;
1051         for (unsigned int j = 0; j < num_glyphs; j++)
1052         {
1053           info->codepoint = glyphs[j];
1054           info->cluster = log_clusters[string_indices[j]];
1055           info++;
1056         }
1057         SCRATCH_RESTORE();
1058       }
1059       {
1060         /* Setup positions.
1061          * Note that CoreText does not return advances for glyphs.  As such,
1062          * for all but last glyph, we use the delta position to next glyph as
1063          * advance (in the advance direction only), and for last glyph we set
1064          * whatever is needed to make the whole run's advance add up. */
1065         SCRATCH_SAVE();
1066         const CGPoint* positions = USE_PTR ? CTRunGetPositionsPtr (run) : NULL;
1067         if (!positions) {
1068           ALLOCATE_ARRAY (CGPoint, position_buf, num_glyphs, goto resize_and_retry);
1069           CTRunGetPositions (run, range_all, position_buf);
1070           positions = position_buf;
1071         }
1072         hb_glyph_info_t *info = run_info;
1073         if (HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction))
1074         {
1075           hb_position_t x_offset = (positions[0].x - advances_so_far) * x_mult;
1076           for (unsigned int j = 0; j < num_glyphs; j++)
1077           {
1078             double advance;
1079             if (likely (j + 1 < num_glyphs))
1080               advance = positions[j + 1].x - positions[j].x;
1081             else /* last glyph */
1082               advance = run_advance - (positions[j].x - positions[0].x);
1083             info->mask = advance * x_mult;
1084             info->var1.i32 = x_offset;
1085             info->var2.i32 = positions[j].y * y_mult;
1086             info++;
1087           }
1088         }
1089         else
1090         {
1091           hb_position_t y_offset = (positions[0].y - advances_so_far) * y_mult;
1092           for (unsigned int j = 0; j < num_glyphs; j++)
1093           {
1094             double advance;
1095             if (likely (j + 1 < num_glyphs))
1096               advance = positions[j + 1].y - positions[j].y;
1097             else /* last glyph */
1098               advance = run_advance - (positions[j].y - positions[0].y);
1099             info->mask = advance * y_mult;
1100             info->var1.i32 = positions[j].x * x_mult;
1101             info->var2.i32 = y_offset;
1102             info++;
1103           }
1104         }
1105         SCRATCH_RESTORE();
1106         advances_so_far += run_advance;
1107       }
1108 #undef SCRATCH_RESTORE
1109 #undef SCRATCH_SAVE
1110 #undef USE_PTR
1111 #undef ALLOCATE_ARRAY
1112
1113       buffer->len += num_glyphs;
1114     }
1115
1116     /* Mac OS 10.6 doesn't have kCTTypesetterOptionForcedEmbeddingLevel,
1117      * or if it does, it doesn't resepct it.  So we get runs with wrong
1118      * directions.  As such, disable the assert...  It wouldn't crash, but
1119      * cursoring will be off...
1120      *
1121      * http://crbug.com/419769
1122      */
1123     if (0)
1124     {
1125       /* Make sure all runs had the expected direction. */
1126       bool backward = HB_DIRECTION_IS_BACKWARD (buffer->props.direction);
1127       assert (bool (status_and & kCTRunStatusRightToLeft) == backward);
1128       assert (bool (status_or  & kCTRunStatusRightToLeft) == backward);
1129     }
1130
1131     buffer->clear_positions ();
1132
1133     unsigned int count = buffer->len;
1134     hb_glyph_info_t *info = buffer->info;
1135     hb_glyph_position_t *pos = buffer->pos;
1136     if (HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction))
1137       for (unsigned int i = 0; i < count; i++)
1138       {
1139         pos->x_advance = info->mask;
1140         pos->x_offset = info->var1.i32;
1141         pos->y_offset = info->var2.i32;
1142         info++, pos++;
1143       }
1144     else
1145       for (unsigned int i = 0; i < count; i++)
1146       {
1147         pos->y_advance = info->mask;
1148         pos->x_offset = info->var1.i32;
1149         pos->y_offset = info->var2.i32;
1150         info++, pos++;
1151       }
1152
1153     /* Fix up clusters so that we never return out-of-order indices;
1154      * if core text has reordered glyphs, we'll merge them to the
1155      * beginning of the reordered cluster.  CoreText is nice enough
1156      * to tell us whenever it has produced nonmonotonic results...
1157      * Note that we assume the input clusters were nonmonotonic to
1158      * begin with.
1159      *
1160      * This does *not* mean we'll form the same clusters as Uniscribe
1161      * or the native OT backend, only that the cluster indices will be
1162      * monotonic in the output buffer. */
1163     if (count > 1 && (status_or & kCTRunStatusNonMonotonic))
1164     {
1165       hb_glyph_info_t *info = buffer->info;
1166       if (HB_DIRECTION_IS_FORWARD (buffer->props.direction))
1167       {
1168         unsigned int cluster = info[count - 1].cluster;
1169         for (unsigned int i = count - 1; i > 0; i--)
1170         {
1171           cluster = MIN (cluster, info[i - 1].cluster);
1172           info[i - 1].cluster = cluster;
1173         }
1174       }
1175       else
1176       {
1177         unsigned int cluster = info[0].cluster;
1178         for (unsigned int i = 1; i < count; i++)
1179         {
1180           cluster = MIN (cluster, info[i].cluster);
1181           info[i].cluster = cluster;
1182         }
1183       }
1184     }
1185   }
1186
1187 #undef FAIL
1188
1189 fail:
1190   if (string_ref)
1191     CFRelease (string_ref);
1192   if (line)
1193     CFRelease (line);
1194
1195   for (unsigned int i = 0; i < range_records.len; i++)
1196     if (range_records[i].font)
1197       CFRelease (range_records[i].font);
1198
1199   return ret;
1200 }
1201
1202
1203 /*
1204  * AAT shaper
1205  */
1206
1207 /*
1208  * shaper face data
1209  */
1210
1211 struct hb_coretext_aat_shaper_face_data_t {};
1212
1213 hb_coretext_aat_shaper_face_data_t *
1214 _hb_coretext_aat_shaper_face_data_create (hb_face_t *face)
1215 {
1216   hb_blob_t *mort_blob = face->reference_table (HB_CORETEXT_TAG_MORT);
1217   /* Umm, we just reference the table to check whether it exists.
1218    * Maybe add better API for this? */
1219   if (!hb_blob_get_length (mort_blob))
1220   {
1221     hb_blob_destroy (mort_blob);
1222     mort_blob = face->reference_table (HB_CORETEXT_TAG_MORX);
1223     if (!hb_blob_get_length (mort_blob))
1224     {
1225       hb_blob_destroy (mort_blob);
1226       return NULL;
1227     }
1228   }
1229   hb_blob_destroy (mort_blob);
1230
1231   return hb_coretext_shaper_face_data_ensure (face) ? (hb_coretext_aat_shaper_face_data_t *) HB_SHAPER_DATA_SUCCEEDED : NULL;
1232 }
1233
1234 void
1235 _hb_coretext_aat_shaper_face_data_destroy (hb_coretext_aat_shaper_face_data_t *data HB_UNUSED)
1236 {
1237 }
1238
1239
1240 /*
1241  * shaper font data
1242  */
1243
1244 struct hb_coretext_aat_shaper_font_data_t {};
1245
1246 hb_coretext_aat_shaper_font_data_t *
1247 _hb_coretext_aat_shaper_font_data_create (hb_font_t *font)
1248 {
1249   return hb_coretext_shaper_font_data_ensure (font) ? (hb_coretext_aat_shaper_font_data_t *) HB_SHAPER_DATA_SUCCEEDED : NULL;
1250 }
1251
1252 void
1253 _hb_coretext_aat_shaper_font_data_destroy (hb_coretext_aat_shaper_font_data_t *data HB_UNUSED)
1254 {
1255 }
1256
1257
1258 /*
1259  * shaper shape_plan data
1260  */
1261
1262 struct hb_coretext_aat_shaper_shape_plan_data_t {};
1263
1264 hb_coretext_aat_shaper_shape_plan_data_t *
1265 _hb_coretext_aat_shaper_shape_plan_data_create (hb_shape_plan_t    *shape_plan HB_UNUSED,
1266                                              const hb_feature_t *user_features HB_UNUSED,
1267                                              unsigned int        num_user_features HB_UNUSED)
1268 {
1269   return (hb_coretext_aat_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
1270 }
1271
1272 void
1273 _hb_coretext_aat_shaper_shape_plan_data_destroy (hb_coretext_aat_shaper_shape_plan_data_t *data HB_UNUSED)
1274 {
1275 }
1276
1277
1278 /*
1279  * shaper
1280  */
1281
1282 hb_bool_t
1283 _hb_coretext_aat_shape (hb_shape_plan_t    *shape_plan,
1284                         hb_font_t          *font,
1285                         hb_buffer_t        *buffer,
1286                         const hb_feature_t *features,
1287                         unsigned int        num_features)
1288 {
1289   return _hb_coretext_shape (shape_plan, font, buffer, features, num_features);
1290 }