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_DEFINE(coretext, face)
  73 HB_SHAPER_DATA_ENSURE_DEFINE(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
 149   /* crbug.com/576941 and crbug.com/625902 and the investigation in the latter
 150    * bug indicate that the cascade list reconfiguration occasionally causes
 151    * crashes in CoreText on OS X 10.9, thus let's skip this step on older
 152    * operating system versions. Except for the emoji font, where _not_
 153    * reconfiguring the cascade list causes CoreText crashes. For details, see
 154    * crbug.com/549610 */
 155   // 0x00070000 stands for "kCTVersionNumber10_10", see CoreText.h
 156   if (&CTGetCoreTextVersion != NULL && CTGetCoreTextVersion() < 0x00070000) {
 157     CFStringRef fontName = CTFontCopyPostScriptName (ct_font);
 158     bool isEmojiFont = CFStringCompare (fontName, CFSTR("AppleColorEmoji"), 0) == kCFCompareEqualTo;
 159     CFRelease (fontName);
 160     if (!isEmojiFont)
 161       return ct_font;
 162   }
 163
 164   CFURLRef original_url = (CFURLRef)CTFontCopyAttribute(ct_font, kCTFontURLAttribute);
 165
 166   /* Create font copy with cascade list that has LastResort first; this speeds up CoreText
 167    * font fallback which we don't need anyway. */
 168   {
 169     CTFontDescriptorRef last_resort_font_desc = get_last_resort_font_desc ();
 170     CTFontRef new_ct_font = CTFontCreateCopyWithAttributes (ct_font, 0.0, NULL, last_resort_font_desc);
 171     CFRelease (last_resort_font_desc);
 172     if (new_ct_font)
 173     {
 174       /* The CTFontCreateCopyWithAttributes call fails to stay on the same font
 175        * when reconfiguring the cascade list and may switch to a different font
 176        * when there are fonts that go by the same name, since the descriptor is
 177        * just name and size.
 178        *
 179        * Avoid reconfiguring the cascade lists if the new font is outside the
 180        * system locations that we cannot access from the sandboxed renderer
 181        * process in Blink. This can be detected by the new file URL location
 182        * that the newly found font points to. */
 183       CFURLRef new_url = (CFURLRef) CTFontCopyAttribute (new_ct_font, kCTFontURLAttribute);
 184       // Keep reconfigured font if URL cannot be retrieved (seems to be the case
 185       // on Mac OS 10.12 Sierra), speculative fix for crbug.com/625606
 186       if (!original_url || !new_url || CFEqual (original_url, new_url)) {
 187         CFRelease (ct_font);
 188         ct_font = new_ct_font;
 189       } else {
 190         CFRelease (new_ct_font);
 191         DEBUG_MSG (CORETEXT, ct_font, "Discarding reconfigured CTFont, location changed.");
 192       }
 193       if (new_url)
 194         CFRelease (new_url);
 195     }
 196     else
 197       DEBUG_MSG (CORETEXT, ct_font, "Font copy with empty cascade list failed");
 198   }
 199
 200   if (original_url)
 201     CFRelease (original_url);
 202   return ct_font;
 203 }
 204
 205 struct hb_coretext_shaper_face_data_t {
 206   CGFontRef cg_font;
 207   CTFontRef ct_font;
 208 };
 209
 210 hb_coretext_shaper_face_data_t *
 211 _hb_coretext_shaper_face_data_create (hb_face_t *face)
 212 {
 213   hb_coretext_shaper_face_data_t *data = (hb_coretext_shaper_face_data_t *) calloc (1, sizeof (hb_coretext_shaper_face_data_t));
 214   if (unlikely (!data))
 215     return NULL;
 216
 217   data->cg_font = create_cg_font (face);
 218   if (unlikely (!data->cg_font))
 219   {
 220     DEBUG_MSG (CORETEXT, face, "CGFont creation failed..");
 221     free (data);
 222     return NULL;
 223   }
 224
 225   /* We use 36pt size instead of UPEM, because CoreText implements the 'trak' table,
 226    * which can make the font too tight at large sizes.  36pt should be a good semi-neutral
 227    * size.
 228    *
 229    * Since we always create CTFont at a fixed size, our CTFont lives in face_data
 230    * instead of font_data.  Which is good, because when people change scale on
 231    * hb_font_t, we won't need to update our CTFont. */
 232   data->ct_font = create_ct_font (data->cg_font, 36.);
 233   if (unlikely (!data->ct_font))
 234   {
 235     DEBUG_MSG (CORETEXT, face, "CTFont creation failed.");
 236     CFRelease (data->cg_font);
 237     free (data);
 238     return NULL;
 239   }
 240
 241   return data;
 242 }
 243
 244 void
 245 _hb_coretext_shaper_face_data_destroy (hb_coretext_shaper_face_data_t *data)
 246 {
 247   CFRelease (data->ct_font);
 248   CFRelease (data->cg_font);
 249   free (data);
 250 }
 251
 252 /*
 253  * Since: 0.9.10
 254  */
 255 CGFontRef
 256 hb_coretext_face_get_cg_font (hb_face_t *face)
 257 {
 258   if (unlikely (!hb_coretext_shaper_face_data_ensure (face))) return NULL;
 259   hb_coretext_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
 260   return face_data->cg_font;
 261 }
 262
 263
 264 /*
 265  * shaper font data
 266  */
 267
 268 struct hb_coretext_shaper_font_data_t {};
 269
 270 hb_coretext_shaper_font_data_t *
 271 _hb_coretext_shaper_font_data_create (hb_font_t *font HB_UNUSED)
 272 {
 273   return (hb_coretext_shaper_font_data_t *) HB_SHAPER_DATA_SUCCEEDED;
 274 }
 275
 276 void
 277 _hb_coretext_shaper_font_data_destroy (hb_coretext_shaper_font_data_t *data)
 278 {
 279 }
 280
 281
 282 /*
 283  * shaper shape_plan data
 284  */
 285
 286 struct hb_coretext_shaper_shape_plan_data_t {};
 287
 288 hb_coretext_shaper_shape_plan_data_t *
 289 _hb_coretext_shaper_shape_plan_data_create (hb_shape_plan_t    *shape_plan HB_UNUSED,
 290                                              const hb_feature_t *user_features HB_UNUSED,
 291                                              unsigned int        num_user_features HB_UNUSED,
 292                                              const int          *coords HB_UNUSED,
 293                                              unsigned int        num_coords HB_UNUSED)
 294 {
 295   return (hb_coretext_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
 296 }
 297
 298 void
 299 _hb_coretext_shaper_shape_plan_data_destroy (hb_coretext_shaper_shape_plan_data_t *data HB_UNUSED)
 300 {
 301 }
 302
 303 CTFontRef
 304 hb_coretext_font_get_ct_font (hb_font_t *font)
 305 {
 306   hb_face_t *face = font->face;
 307   if (unlikely (!hb_coretext_shaper_face_data_ensure (face))) return NULL;
 308   hb_coretext_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
 309   return face_data->ct_font;
 310 }
 311
 312
 313 /*
 314  * shaper
 315  */
 316
 317 struct feature_record_t {
 318   unsigned int feature;
 319   unsigned int setting;
 320 };
 321
 322 struct active_feature_t {
 323   feature_record_t rec;
 324   unsigned int order;
 325
 326   static int cmp (const active_feature_t *a, const active_feature_t *b) {
 327     return a->rec.feature < b->rec.feature ? -1 : a->rec.feature > b->rec.feature ? 1 :
 328            a->order < b->order ? -1 : a->order > b->order ? 1 :
 329            a->rec.setting < b->rec.setting ? -1 : a->rec.setting > b->rec.setting ? 1 :
 330            0;
 331   }
 332   bool operator== (const active_feature_t *f) {
 333     return cmp (this, f) == 0;
 334   }
 335 };
 336
 337 struct feature_event_t {
 338   unsigned int index;
 339   bool start;
 340   active_feature_t feature;
 341
 342   static int cmp (const feature_event_t *a, const feature_event_t *b) {
 343     return a->index < b->index ? -1 : a->index > b->index ? 1 :
 344            a->start < b->start ? -1 : a->start > b->start ? 1 :
 345            active_feature_t::cmp (&a->feature, &b->feature);
 346   }
 347 };
 348
 349 struct range_record_t {
 350   CTFontRef font;
 351   unsigned int index_first; /* == start */
 352   unsigned int index_last;  /* == end - 1 */
 353 };
 354
 355
 356 /* The following enum members are added in OS X 10.8. */
 357 #define kAltHalfWidthTextSelector               6
 358 #define kAltProportionalTextSelector            5
 359 #define kAlternateHorizKanaOffSelector          1
 360 #define kAlternateHorizKanaOnSelector           0
 361 #define kAlternateKanaType                      34
 362 #define kAlternateVertKanaOffSelector           3
 363 #define kAlternateVertKanaOnSelector            2
 364 #define kCaseSensitiveLayoutOffSelector         1
 365 #define kCaseSensitiveLayoutOnSelector          0
 366 #define kCaseSensitiveLayoutType                33
 367 #define kCaseSensitiveSpacingOffSelector        3
 368 #define kCaseSensitiveSpacingOnSelector         2
 369 #define kContextualAlternatesOffSelector        1
 370 #define kContextualAlternatesOnSelector         0
 371 #define kContextualAlternatesType               36
 372 #define kContextualLigaturesOffSelector         19
 373 #define kContextualLigaturesOnSelector          18
 374 #define kContextualSwashAlternatesOffSelector   5
 375 #define kContextualSwashAlternatesOnSelector    4
 376 #define kDefaultLowerCaseSelector               0
 377 #define kDefaultUpperCaseSelector               0
 378 #define kHistoricalLigaturesOffSelector         21
 379 #define kHistoricalLigaturesOnSelector          20
 380 #define kHojoCharactersSelector                 12
 381 #define kJIS2004CharactersSelector              11
 382 #define kLowerCasePetiteCapsSelector            2
 383 #define kLowerCaseSmallCapsSelector             1
 384 #define kLowerCaseType                          37
 385 #define kMathematicalGreekOffSelector           11
 386 #define kMathematicalGreekOnSelector            10
 387 #define kNLCCharactersSelector                  13
 388 #define kQuarterWidthTextSelector               4
 389 #define kScientificInferiorsSelector            4
 390 #define kStylisticAltEightOffSelector           17
 391 #define kStylisticAltEightOnSelector            16
 392 #define kStylisticAltEighteenOffSelector        37
 393 #define kStylisticAltEighteenOnSelector         36
 394 #define kStylisticAltElevenOffSelector          23
 395 #define kStylisticAltElevenOnSelector           22
 396 #define kStylisticAltFifteenOffSelector         31
 397 #define kStylisticAltFifteenOnSelector          30
 398 #define kStylisticAltFiveOffSelector            11
 399 #define kStylisticAltFiveOnSelector             10
 400 #define kStylisticAltFourOffSelector            9
 401 #define kStylisticAltFourOnSelector             8
 402 #define kStylisticAltFourteenOffSelector        29
 403 #define kStylisticAltFourteenOnSelector         28
 404 #define kStylisticAltNineOffSelector            19
 405 #define kStylisticAltNineOnSelector             18
 406 #define kStylisticAltNineteenOffSelector        39
 407 #define kStylisticAltNineteenOnSelector         38
 408 #define kStylisticAltOneOffSelector             3
 409 #define kStylisticAltOneOnSelector              2
 410 #define kStylisticAltSevenOffSelector           15
 411 #define kStylisticAltSevenOnSelector            14
 412 #define kStylisticAltSeventeenOffSelector       35
 413 #define kStylisticAltSeventeenOnSelector        34
 414 #define kStylisticAltSixOffSelector             13
 415 #define kStylisticAltSixOnSelector              12
 416 #define kStylisticAltSixteenOffSelector         33
 417 #define kStylisticAltSixteenOnSelector          32
 418 #define kStylisticAltTenOffSelector             21
 419 #define kStylisticAltTenOnSelector              20
 420 #define kStylisticAltThirteenOffSelector        27
 421 #define kStylisticAltThirteenOnSelector         26
 422 #define kStylisticAltThreeOffSelector           7
 423 #define kStylisticAltThreeOnSelector            6
 424 #define kStylisticAltTwelveOffSelector          25
 425 #define kStylisticAltTwelveOnSelector           24
 426 #define kStylisticAltTwentyOffSelector          41
 427 #define kStylisticAltTwentyOnSelector           40
 428 #define kStylisticAltTwoOffSelector             5
 429 #define kStylisticAltTwoOnSelector              4
 430 #define kStylisticAlternativesType              35
 431 #define kSwashAlternatesOffSelector             3
 432 #define kSwashAlternatesOnSelector              2
 433 #define kThirdWidthTextSelector                 3
 434 #define kTraditionalNamesCharactersSelector     14
 435 #define kUpperCasePetiteCapsSelector            2
 436 #define kUpperCaseSmallCapsSelector             1
 437 #define kUpperCaseType                          38
 438
 439 /* Table data courtesy of Apple. */
 440 static const struct feature_mapping_t {
 441     FourCharCode otFeatureTag;
 442     uint16_t aatFeatureType;
 443     uint16_t selectorToEnable;
 444     uint16_t selectorToDisable;
 445 } feature_mappings[] = {
 446     { 'c2pc',   kUpperCaseType,             kUpperCasePetiteCapsSelector,           kDefaultUpperCaseSelector },
 447     { 'c2sc',   kUpperCaseType,             kUpperCaseSmallCapsSelector,            kDefaultUpperCaseSelector },
 448     { 'calt',   kContextualAlternatesType,  kContextualAlternatesOnSelector,        kContextualAlternatesOffSelector },
 449     { 'case',   kCaseSensitiveLayoutType,   kCaseSensitiveLayoutOnSelector,         kCaseSensitiveLayoutOffSelector },
 450     { 'clig',   kLigaturesType,             kContextualLigaturesOnSelector,         kContextualLigaturesOffSelector },
 451     { 'cpsp',   kCaseSensitiveLayoutType,   kCaseSensitiveSpacingOnSelector,        kCaseSensitiveSpacingOffSelector },
 452     { 'cswh',   kContextualAlternatesType,  kContextualSwashAlternatesOnSelector,   kContextualSwashAlternatesOffSelector },
 453     { 'dlig',   kLigaturesType,             kRareLigaturesOnSelector,               kRareLigaturesOffSelector },
 454     { 'expt',   kCharacterShapeType,        kExpertCharactersSelector,              16 },
 455     { 'frac',   kFractionsType,             kDiagonalFractionsSelector,             kNoFractionsSelector },
 456     { 'fwid',   kTextSpacingType,           kMonospacedTextSelector,                7 },
 457     { 'halt',   kTextSpacingType,           kAltHalfWidthTextSelector,              7 },
 458     { 'hist',   kLigaturesType,             kHistoricalLigaturesOnSelector,         kHistoricalLigaturesOffSelector },
 459     { 'hkna',   kAlternateKanaType,         kAlternateHorizKanaOnSelector,          kAlternateHorizKanaOffSelector, },
 460     { 'hlig',   kLigaturesType,             kHistoricalLigaturesOnSelector,         kHistoricalLigaturesOffSelector },
 461     { 'hngl',   kTransliterationType,       kHanjaToHangulSelector,                 kNoTransliterationSelector },
 462     { 'hojo',   kCharacterShapeType,        kHojoCharactersSelector,                16 },
 463     { 'hwid',   kTextSpacingType,           kHalfWidthTextSelector,                 7 },
 464     { 'ital',   kItalicCJKRomanType,        kCJKItalicRomanOnSelector,              kCJKItalicRomanOffSelector },
 465     { 'jp04',   kCharacterShapeType,        kJIS2004CharactersSelector,             16 },
 466     { 'jp78',   kCharacterShapeType,        kJIS1978CharactersSelector,             16 },
 467     { 'jp83',   kCharacterShapeType,        kJIS1983CharactersSelector,             16 },
 468     { 'jp90',   kCharacterShapeType,        kJIS1990CharactersSelector,             16 },
 469     { 'liga',   kLigaturesType,             kCommonLigaturesOnSelector,             kCommonLigaturesOffSelector },
 470     { 'lnum',   kNumberCaseType,            kUpperCaseNumbersSelector,              2 },
 471     { 'mgrk',   kMathematicalExtrasType,    kMathematicalGreekOnSelector,           kMathematicalGreekOffSelector },
 472     { 'nlck',   kCharacterShapeType,        kNLCCharactersSelector,                 16 },
 473     { 'onum',   kNumberCaseType,            kLowerCaseNumbersSelector,              2 },
 474     { 'ordn',   kVerticalPositionType,      kOrdinalsSelector,                      kNormalPositionSelector },
 475     { 'palt',   kTextSpacingType,           kAltProportionalTextSelector,           7 },
 476     { 'pcap',   kLowerCaseType,             kLowerCasePetiteCapsSelector,           kDefaultLowerCaseSelector },
 477     { 'pkna',   kTextSpacingType,           kProportionalTextSelector,              7 },
 478     { 'pnum',   kNumberSpacingType,         kProportionalNumbersSelector,           4 },
 479     { 'pwid',   kTextSpacingType,           kProportionalTextSelector,              7 },
 480     { 'qwid',   kTextSpacingType,           kQuarterWidthTextSelector,              7 },
 481     { 'ruby',   kRubyKanaType,              kRubyKanaOnSelector,                    kRubyKanaOffSelector },
 482     { 'sinf',   kVerticalPositionType,      kScientificInferiorsSelector,           kNormalPositionSelector },
 483     { 'smcp',   kLowerCaseType,             kLowerCaseSmallCapsSelector,            kDefaultLowerCaseSelector },
 484     { 'smpl',   kCharacterShapeType,        kSimplifiedCharactersSelector,          16 },
 485     { 'ss01',   kStylisticAlternativesType, kStylisticAltOneOnSelector,             kStylisticAltOneOffSelector },
 486     { 'ss02',   kStylisticAlternativesType, kStylisticAltTwoOnSelector,             kStylisticAltTwoOffSelector },
 487     { 'ss03',   kStylisticAlternativesType, kStylisticAltThreeOnSelector,           kStylisticAltThreeOffSelector },
 488     { 'ss04',   kStylisticAlternativesType, kStylisticAltFourOnSelector,            kStylisticAltFourOffSelector },
 489     { 'ss05',   kStylisticAlternativesType, kStylisticAltFiveOnSelector,            kStylisticAltFiveOffSelector },
 490     { 'ss06',   kStylisticAlternativesType, kStylisticAltSixOnSelector,             kStylisticAltSixOffSelector },
 491     { 'ss07',   kStylisticAlternativesType, kStylisticAltSevenOnSelector,           kStylisticAltSevenOffSelector },
 492     { 'ss08',   kStylisticAlternativesType, kStylisticAltEightOnSelector,           kStylisticAltEightOffSelector },
 493     { 'ss09',   kStylisticAlternativesType, kStylisticAltNineOnSelector,            kStylisticAltNineOffSelector },
 494     { 'ss10',   kStylisticAlternativesType, kStylisticAltTenOnSelector,             kStylisticAltTenOffSelector },
 495     { 'ss11',   kStylisticAlternativesType, kStylisticAltElevenOnSelector,          kStylisticAltElevenOffSelector },
 496     { 'ss12',   kStylisticAlternativesType, kStylisticAltTwelveOnSelector,          kStylisticAltTwelveOffSelector },
 497     { 'ss13',   kStylisticAlternativesType, kStylisticAltThirteenOnSelector,        kStylisticAltThirteenOffSelector },
 498     { 'ss14',   kStylisticAlternativesType, kStylisticAltFourteenOnSelector,        kStylisticAltFourteenOffSelector },
 499     { 'ss15',   kStylisticAlternativesType, kStylisticAltFifteenOnSelector,         kStylisticAltFifteenOffSelector },
 500     { 'ss16',   kStylisticAlternativesType, kStylisticAltSixteenOnSelector,         kStylisticAltSixteenOffSelector },
 501     { 'ss17',   kStylisticAlternativesType, kStylisticAltSeventeenOnSelector,       kStylisticAltSeventeenOffSelector },
 502     { 'ss18',   kStylisticAlternativesType, kStylisticAltEighteenOnSelector,        kStylisticAltEighteenOffSelector },
 503     { 'ss19',   kStylisticAlternativesType, kStylisticAltNineteenOnSelector,        kStylisticAltNineteenOffSelector },
 504     { 'ss20',   kStylisticAlternativesType, kStylisticAltTwentyOnSelector,          kStylisticAltTwentyOffSelector },
 505     { 'subs',   kVerticalPositionType,      kInferiorsSelector,                     kNormalPositionSelector },
 506     { 'sups',   kVerticalPositionType,      kSuperiorsSelector,                     kNormalPositionSelector },
 507     { 'swsh',   kContextualAlternatesType,  kSwashAlternatesOnSelector,             kSwashAlternatesOffSelector },
 508     { 'titl',   kStyleOptionsType,          kTitlingCapsSelector,                   kNoStyleOptionsSelector },
 509     { 'tnam',   kCharacterShapeType,        kTraditionalNamesCharactersSelector,    16 },
 510     { 'tnum',   kNumberSpacingType,         kMonospacedNumbersSelector,             4 },
 511     { 'trad',   kCharacterShapeType,        kTraditionalCharactersSelector,         16 },
 512     { 'twid',   kTextSpacingType,           kThirdWidthTextSelector,                7 },
 513     { 'unic',   kLetterCaseType,            14,                                     15 },
 514     { 'valt',   kTextSpacingType,           kAltProportionalTextSelector,           7 },
 515     { 'vert',   kVerticalSubstitutionType,  kSubstituteVerticalFormsOnSelector,     kSubstituteVerticalFormsOffSelector },
 516     { 'vhal',   kTextSpacingType,           kAltHalfWidthTextSelector,              7 },
 517     { 'vkna',   kAlternateKanaType,         kAlternateVertKanaOnSelector,           kAlternateVertKanaOffSelector },
 518     { 'vpal',   kTextSpacingType,           kAltProportionalTextSelector,           7 },
 519     { 'vrt2',   kVerticalSubstitutionType,  kSubstituteVerticalFormsOnSelector,     kSubstituteVerticalFormsOffSelector },
 520     { 'zero',   kTypographicExtrasType,     kSlashedZeroOnSelector,                 kSlashedZeroOffSelector },
 521 };
 522
 523 static int
 524 _hb_feature_mapping_cmp (const void *key_, const void *entry_)
 525 {
 526   unsigned int key = * (unsigned int *) key_;
 527   const feature_mapping_t * entry = (const feature_mapping_t *) entry_;
 528   return key < entry->otFeatureTag ? -1 :
 529          key > entry->otFeatureTag ? 1 :
 530          0;
 531 }
 532
 533 hb_bool_t
 534 _hb_coretext_shape (hb_shape_plan_t    *shape_plan,
 535                     hb_font_t          *font,
 536                     hb_buffer_t        *buffer,
 537                     const hb_feature_t *features,
 538                     unsigned int        num_features)
 539 {
 540   hb_face_t *face = font->face;
 541   hb_coretext_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
 542
 543   CGFloat ct_font_size = CTFontGetSize (face_data->ct_font);
 544   CGFloat x_mult = (CGFloat) font->x_scale / ct_font_size;
 545   CGFloat y_mult = (CGFloat) font->y_scale / ct_font_size;
 546
 547   /* Attach marks to their bases, to match the 'ot' shaper.
 548    * Adapted from hb-ot-shape:hb_form_clusters().
 549    * Note that this only makes us be closer to the 'ot' shaper,
 550    * but by no means the same.  For example, if there's
 551    * B1 M1 B2 M2, and B1-B2 form a ligature, M2's cluster will
 552    * continue pointing to B2 even though B2 was merged into B1's
 553    * cluster... */
 554   if (buffer->cluster_level == HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES)
 555   {
 556     hb_unicode_funcs_t *unicode = buffer->unicode;
 557     unsigned int count = buffer->len;
 558     hb_glyph_info_t *info = buffer->info;
 559     for (unsigned int i = 1; i < count; i++)
 560       if (HB_UNICODE_GENERAL_CATEGORY_IS_MARK (unicode->general_category (info[i].codepoint)))
 561         buffer->merge_clusters (i - 1, i + 1);
 562   }
 563
 564   hb_auto_array_t<feature_record_t> feature_records;
 565   hb_auto_array_t<range_record_t> range_records;
 566
 567   /*
 568    * Set up features.
 569    * (copied + modified from code from hb-uniscribe.cc)
 570    */
 571   if (num_features)
 572   {
 573     /* Sort features by start/end events. */
 574     hb_auto_array_t<feature_event_t> feature_events;
 575     for (unsigned int i = 0; i < num_features; i++)
 576     {
 577       const feature_mapping_t * mapping = (const feature_mapping_t *) bsearch (&features[i].tag,
 578                                                                                feature_mappings,
 579                                                                                ARRAY_LENGTH (feature_mappings),
 580                                                                                sizeof (feature_mappings[0]),
 581                                                                                _hb_feature_mapping_cmp);
 582       if (!mapping)
 583         continue;
 584
 585       active_feature_t feature;
 586       feature.rec.feature = mapping->aatFeatureType;
 587       feature.rec.setting = features[i].value ? mapping->selectorToEnable : mapping->selectorToDisable;
 588       feature.order = i;
 589
 590       feature_event_t *event;
 591
 592       event = feature_events.push ();
 593       if (unlikely (!event))
 594         goto fail_features;
 595       event->index = features[i].start;
 596       event->start = true;
 597       event->feature = feature;
 598
 599       event = feature_events.push ();
 600       if (unlikely (!event))
 601         goto fail_features;
 602       event->index = features[i].end;
 603       event->start = false;
 604       event->feature = feature;
 605     }
 606     feature_events.qsort ();
 607     /* Add a strategic final event. */
 608     {
 609       active_feature_t feature;
 610       feature.rec.feature = HB_TAG_NONE;
 611       feature.rec.setting = 0;
 612       feature.order = num_features + 1;
 613
 614       feature_event_t *event = feature_events.push ();
 615       if (unlikely (!event))
 616         goto fail_features;
 617       event->index = 0; /* This value does magic. */
 618       event->start = false;
 619       event->feature = feature;
 620     }
 621
 622     /* Scan events and save features for each range. */
 623     hb_auto_array_t<active_feature_t> active_features;
 624     unsigned int last_index = 0;
 625     for (unsigned int i = 0; i < feature_events.len; i++)
 626     {
 627       feature_event_t *event = &feature_events[i];
 628
 629       if (event->index != last_index)
 630       {
 631         /* Save a snapshot of active features and the range. */
 632         range_record_t *range = range_records.push ();
 633         if (unlikely (!range))
 634           goto fail_features;
 635
 636         if (active_features.len)
 637         {
 638           CFMutableArrayRef features_array = CFArrayCreateMutable(kCFAllocatorDefault, 0, &kCFTypeArrayCallBacks);
 639
 640           /* TODO sort and resolve conflicting features? */
 641           /* active_features.qsort (); */
 642           for (unsigned int j = 0; j < active_features.len; j++)
 643           {
 644             CFStringRef keys[2] = {
 645               kCTFontFeatureTypeIdentifierKey,
 646               kCTFontFeatureSelectorIdentifierKey
 647             };
 648             CFNumberRef values[2] = {
 649               CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &active_features[j].rec.feature),
 650               CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &active_features[j].rec.setting)
 651             };
 652             CFDictionaryRef dict = CFDictionaryCreate (kCFAllocatorDefault,
 653                                                        (const void **) keys,
 654                                                        (const void **) values,
 655                                                        2,
 656                                                        &kCFTypeDictionaryKeyCallBacks,
 657                                                        &kCFTypeDictionaryValueCallBacks);
 658             CFRelease (values[0]);
 659             CFRelease (values[1]);
 660
 661             CFArrayAppendValue (features_array, dict);
 662             CFRelease (dict);
 663
 664           }
 665
 666           CFDictionaryRef attributes = CFDictionaryCreate (kCFAllocatorDefault,
 667                                                            (const void **) &kCTFontFeatureSettingsAttribute,
 668                                                            (const void **) &features_array,
 669                                                            1,
 670                                                            &kCFTypeDictionaryKeyCallBacks,
 671                                                            &kCFTypeDictionaryValueCallBacks);
 672           CFRelease (features_array);
 673
 674           CTFontDescriptorRef font_desc = CTFontDescriptorCreateWithAttributes (attributes);
 675           CFRelease (attributes);
 676
 677           range->font = CTFontCreateCopyWithAttributes (face_data->ct_font, 0.0, NULL, font_desc);
 678           CFRelease (font_desc);
 679         }
 680         else
 681         {
 682           range->font = NULL;
 683         }
 684
 685         range->index_first = last_index;
 686         range->index_last  = event->index - 1;
 687
 688         last_index = event->index;
 689       }
 690
 691       if (event->start) {
 692         active_feature_t *feature = active_features.push ();
 693         if (unlikely (!feature))
 694           goto fail_features;
 695         *feature = event->feature;
 696       } else {
 697         active_feature_t *feature = active_features.find (&event->feature);
 698         if (feature)
 699           active_features.remove (feature - active_features.array);
 700       }
 701     }
 702
 703     if (!range_records.len) /* No active feature found. */
 704       goto fail_features;
 705   }
 706   else
 707   {
 708   fail_features:
 709     num_features = 0;
 710   }
 711
 712   unsigned int scratch_size;
 713   hb_buffer_t::scratch_buffer_t *scratch = buffer->get_scratch_buffer (&scratch_size);
 714
 715 #define ALLOCATE_ARRAY(Type, name, len, on_no_room) \
 716   Type *name = (Type *) scratch; \
 717   { \
 718     unsigned int _consumed = DIV_CEIL ((len) * sizeof (Type), sizeof (*scratch)); \
 719     if (unlikely (_consumed > scratch_size)) \
 720     { \
 721       on_no_room; \
 722       assert (0); \
 723     } \
 724     scratch += _consumed; \
 725     scratch_size -= _consumed; \
 726   }
 727
 728   ALLOCATE_ARRAY (UniChar, pchars, buffer->len * 2, /*nothing*/);
 729   unsigned int chars_len = 0;
 730   for (unsigned int i = 0; i < buffer->len; i++) {
 731     hb_codepoint_t c = buffer->info[i].codepoint;
 732     if (likely (c <= 0xFFFFu))
 733       pchars[chars_len++] = c;
 734     else if (unlikely (c > 0x10FFFFu))
 735       pchars[chars_len++] = 0xFFFDu;
 736     else {
 737       pchars[chars_len++] = 0xD800u + ((c - 0x10000u) >> 10);
 738       pchars[chars_len++] = 0xDC00u + ((c - 0x10000u) & ((1u << 10) - 1));
 739     }
 740   }
 741
 742   ALLOCATE_ARRAY (unsigned int, log_clusters, chars_len, /*nothing*/);
 743   chars_len = 0;
 744   for (unsigned int i = 0; i < buffer->len; i++)
 745   {
 746     hb_codepoint_t c = buffer->info[i].codepoint;
 747     unsigned int cluster = buffer->info[i].cluster;
 748     log_clusters[chars_len++] = cluster;
 749     if (hb_in_range (c, 0x10000u, 0x10FFFFu))
 750       log_clusters[chars_len++] = cluster; /* Surrogates. */
 751   }
 752
 753 #define FAIL(...) \
 754   HB_STMT_START { \
 755     DEBUG_MSG (CORETEXT, NULL, __VA_ARGS__); \
 756     ret = false; \
 757     goto fail; \
 758   } HB_STMT_END;
 759
 760   bool ret = true;
 761   CFStringRef string_ref = NULL;
 762   CTLineRef line = NULL;
 763
 764   if (0)
 765   {
 766 resize_and_retry:
 767     DEBUG_MSG (CORETEXT, buffer, "Buffer resize");
 768     /* string_ref uses the scratch-buffer for backing store, and line references
 769      * string_ref (via attr_string).  We must release those before resizing buffer. */
 770     assert (string_ref);
 771     assert (line);
 772     CFRelease (string_ref);
 773     CFRelease (line);
 774     string_ref = NULL;
 775     line = NULL;
 776
 777     /* Get previous start-of-scratch-area, that we use later for readjusting
 778      * our existing scratch arrays. */
 779     unsigned int old_scratch_used;
 780     hb_buffer_t::scratch_buffer_t *old_scratch;
 781     old_scratch = buffer->get_scratch_buffer (&old_scratch_used);
 782     old_scratch_used = scratch - old_scratch;
 783
 784     if (unlikely (!buffer->ensure (buffer->allocated * 2)))
 785       FAIL ("Buffer resize failed");
 786
 787     /* Adjust scratch, pchars, and log_cluster arrays.  This is ugly, but really the
 788      * cleanest way to do without completely restructuring the rest of this shaper. */
 789     scratch = buffer->get_scratch_buffer (&scratch_size);
 790     pchars = reinterpret_cast<UniChar *> (((char *) scratch + ((char *) pchars - (char *) old_scratch)));
 791     log_clusters = reinterpret_cast<unsigned int *> (((char *) scratch + ((char *) log_clusters - (char *) old_scratch)));
 792     scratch += old_scratch_used;
 793     scratch_size -= old_scratch_used;
 794   }
 795   {
 796     string_ref = CFStringCreateWithCharactersNoCopy (NULL,
 797                                                      pchars, chars_len,
 798                                                      kCFAllocatorNull);
 799     if (unlikely (!string_ref))
 800       FAIL ("CFStringCreateWithCharactersNoCopy failed");
 801
 802     /* Create an attributed string, populate it, and create a line from it, then release attributed string. */
 803     {
 804       CFMutableAttributedStringRef attr_string = CFAttributedStringCreateMutable (kCFAllocatorDefault,
 805                                                                                   chars_len);
 806       if (unlikely (!attr_string))
 807         FAIL ("CFAttributedStringCreateMutable failed");
 808       CFAttributedStringReplaceString (attr_string, CFRangeMake (0, 0), string_ref);
 809       if (HB_DIRECTION_IS_VERTICAL (buffer->props.direction))
 810       {
 811         CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
 812                                         kCTVerticalFormsAttributeName, kCFBooleanTrue);
 813       }
 814
 815       if (buffer->props.language)
 816       {
 817 /* What's the iOS equivalent of this check?
 818  * The symbols was introduced in iOS 7.0.
 819  * At any rate, our fallback is safe and works fine. */
 820 #if MAC_OS_X_VERSION_MIN_REQUIRED < 1090
 821 #  define kCTLanguageAttributeName CFSTR ("NSLanguage")
 822 #endif
 823         CFStringRef lang = CFStringCreateWithCStringNoCopy (kCFAllocatorDefault,
 824                                                             hb_language_to_string (buffer->props.language),
 825                                                             kCFStringEncodingUTF8,
 826                                                             kCFAllocatorNull);
 827         if (unlikely (!lang))
 828           FAIL ("CFStringCreateWithCStringNoCopy failed");
 829         CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
 830                                         kCTLanguageAttributeName, lang);
 831         CFRelease (lang);
 832       }
 833       CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
 834                                       kCTFontAttributeName, face_data->ct_font);
 835
 836       if (num_features)
 837       {
 838         unsigned int start = 0;
 839         range_record_t *last_range = &range_records[0];
 840         for (unsigned int k = 0; k < chars_len; k++)
 841         {
 842           range_record_t *range = last_range;
 843           while (log_clusters[k] < range->index_first)
 844             range--;
 845           while (log_clusters[k] > range->index_last)
 846             range++;
 847           if (range != last_range)
 848           {
 849             if (last_range->font)
 850               CFAttributedStringSetAttribute (attr_string, CFRangeMake (start, k - start),
 851                                               kCTFontAttributeName, last_range->font);
 852
 853             start = k;
 854           }
 855
 856           last_range = range;
 857         }
 858         if (start != chars_len && last_range->font)
 859           CFAttributedStringSetAttribute (attr_string, CFRangeMake (start, chars_len - start),
 860                                           kCTFontAttributeName, last_range->font);
 861       }
 862
 863       int level = HB_DIRECTION_IS_FORWARD (buffer->props.direction) ? 0 : 1;
 864       CFNumberRef level_number = CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &level);
 865       CFDictionaryRef options = CFDictionaryCreate (kCFAllocatorDefault,
 866                                                     (const void **) &kCTTypesetterOptionForcedEmbeddingLevel,
 867                                                     (const void **) &level_number,
 868                                                     1,
 869                                                     &kCFTypeDictionaryKeyCallBacks,
 870                                                     &kCFTypeDictionaryValueCallBacks);
 871       if (unlikely (!options))
 872         FAIL ("CFDictionaryCreate failed");
 873
 874       CTTypesetterRef typesetter = CTTypesetterCreateWithAttributedStringAndOptions (attr_string, options);
 875       CFRelease (options);
 876       CFRelease (attr_string);
 877       if (unlikely (!typesetter))
 878         FAIL ("CTTypesetterCreateWithAttributedStringAndOptions failed");
 879
 880       line = CTTypesetterCreateLine (typesetter, CFRangeMake(0, 0));
 881       CFRelease (typesetter);
 882       if (unlikely (!line))
 883         FAIL ("CTTypesetterCreateLine failed");
 884     }
 885
 886     CFArrayRef glyph_runs = CTLineGetGlyphRuns (line);
 887     unsigned int num_runs = CFArrayGetCount (glyph_runs);
 888     DEBUG_MSG (CORETEXT, NULL, "Num runs: %d", num_runs);
 889
 890     buffer->len = 0;
 891     uint32_t status_and = ~0, status_or = 0;
 892     double advances_so_far = 0;
 893     /* For right-to-left runs, CoreText returns the glyphs positioned such that
 894      * any trailing whitespace is to the left of (0,0).  Adjust coordinate system
 895      * to fix for that.  Test with any RTL string with trailing spaces.
 896      * https://code.google.com/p/chromium/issues/detail?id=469028
 897      */
 898     if (HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
 899     {
 900       advances_so_far -= CTLineGetTrailingWhitespaceWidth (line);
 901       if (HB_DIRECTION_IS_VERTICAL (buffer->props.direction))
 902           advances_so_far = -advances_so_far;
 903     }
 904
 905     const CFRange range_all = CFRangeMake (0, 0);
 906
 907     for (unsigned int i = 0; i < num_runs; i++)
 908     {
 909       CTRunRef run = static_cast<CTRunRef>(CFArrayGetValueAtIndex (glyph_runs, i));
 910       CTRunStatus run_status = CTRunGetStatus (run);
 911       status_or  |= run_status;
 912       status_and &= run_status;
 913       DEBUG_MSG (CORETEXT, run, "CTRunStatus: %x", run_status);
 914       double run_advance = CTRunGetTypographicBounds (run, range_all, NULL, NULL, NULL);
 915       if (HB_DIRECTION_IS_VERTICAL (buffer->props.direction))
 916           run_advance = -run_advance;
 917       DEBUG_MSG (CORETEXT, run, "Run advance: %g", run_advance);
 918
 919       /* CoreText does automatic font fallback (AKA "cascading") for  characters
 920        * not supported by the requested font, and provides no way to turn it off,
 921        * so we must detect if the returned run uses a font other than the requested
 922        * one and fill in the buffer with .notdef glyphs instead of random glyph
 923        * indices from a different font.
 924        */
 925       CFDictionaryRef attributes = CTRunGetAttributes (run);
 926       CTFontRef run_ct_font = static_cast<CTFontRef>(CFDictionaryGetValue (attributes, kCTFontAttributeName));
 927       if (!CFEqual (run_ct_font, face_data->ct_font))
 928       {
 929         /* The run doesn't use our main font instance.  We have to figure out
 930          * whether font fallback happened, or this is just CoreText giving us
 931          * another CTFont using the same underlying CGFont.  CoreText seems
 932          * to do that in a variety of situations, one of which being vertical
 933          * text, but also perhaps for caching reasons.
 934          *
 935          * First, see if it uses any of our subfonts created to set font features...
 936          *
 937          * Next, compare the CGFont to the one we used to create our fonts.
 938          * Even this doesn't work all the time.
 939          *
 940          * Finally, we compare PS names, which I don't think are unique...
 941          *
 942          * Looks like if we really want to be sure here we have to modify the
 943          * font to change the name table, similar to what we do in the uniscribe
 944          * backend.
 945          *
 946          * However, even that wouldn't work if we were passed in the CGFont to
 947          * construct a hb_face to begin with.
 948          *
 949          * See: http://github.com/behdad/harfbuzz/pull/36
 950          *
 951          * Also see: https://bugs.chromium.org/p/chromium/issues/detail?id=597098
 952          */
 953         bool matched = false;
 954         for (unsigned int i = 0; i < range_records.len; i++)
 955           if (range_records[i].font && CFEqual (run_ct_font, range_records[i].font))
 956           {
 957             matched = true;
 958             break;
 959           }
 960         if (!matched)
 961         {
 962           CGFontRef run_cg_font = CTFontCopyGraphicsFont (run_ct_font, 0);
 963           if (run_cg_font)
 964           {
 965             matched = CFEqual (run_cg_font, face_data->cg_font);
 966             CFRelease (run_cg_font);
 967           }
 968         }
 969         if (!matched)
 970         {
 971           CFStringRef font_ps_name = CTFontCopyName (face_data->ct_font, kCTFontPostScriptNameKey);
 972           CFStringRef run_ps_name = CTFontCopyName (run_ct_font, kCTFontPostScriptNameKey);
 973           CFComparisonResult result = CFStringCompare (run_ps_name, font_ps_name, 0);
 974           CFRelease (run_ps_name);
 975           CFRelease (font_ps_name);
 976           if (result == kCFCompareEqualTo)
 977             matched = true;
 978         }
 979         if (!matched)
 980         {
 981           CFRange range = CTRunGetStringRange (run);
 982           DEBUG_MSG (CORETEXT, run, "Run used fallback font: %ld..%ld",
 983                      range.location, range.location + range.length);
 984           if (!buffer->ensure_inplace (buffer->len + range.length))
 985             goto resize_and_retry;
 986           hb_glyph_info_t *info = buffer->info + buffer->len;
 987
 988           hb_codepoint_t notdef = 0;
 989           hb_direction_t dir = buffer->props.direction;
 990           hb_position_t x_advance, y_advance, x_offset, y_offset;
 991           hb_font_get_glyph_advance_for_direction (font, notdef, dir, &x_advance, &y_advance);
 992           hb_font_get_glyph_origin_for_direction (font, notdef, dir, &x_offset, &y_offset);
 993           hb_position_t advance = x_advance + y_advance;
 994           x_offset = -x_offset;
 995           y_offset = -y_offset;
 996
 997           unsigned int old_len = buffer->len;
 998           for (CFIndex j = range.location; j < range.location + range.length; j++)
 999           {
1000               UniChar ch = CFStringGetCharacterAtIndex (string_ref, j);
1001               if (hb_in_range<UniChar> (ch, 0xDC00u, 0xDFFFu) && range.location < j)
1002               {
1003                 ch = CFStringGetCharacterAtIndex (string_ref, j - 1);
1004                 if (hb_in_range<UniChar> (ch, 0xD800u, 0xDBFFu))
1005                   /* This is the second of a surrogate pair.  Don't need .notdef
1006                    * for this one. */
1007                   continue;
1008               }
1009               if (buffer->unicode->is_default_ignorable (ch))
1010                 continue;
1011
1012               info->codepoint = notdef;
1013               info->cluster = log_clusters[j];
1014
1015               info->mask = advance;
1016               info->var1.i32 = x_offset;
1017               info->var2.i32 = y_offset;
1018
1019               info++;
1020               buffer->len++;
1021           }
1022           if (HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
1023             buffer->reverse_range (old_len, buffer->len);
1024           advances_so_far += run_advance;
1025           continue;
1026         }
1027       }
1028
1029       unsigned int num_glyphs = CTRunGetGlyphCount (run);
1030       if (num_glyphs == 0)
1031         continue;
1032
1033       if (!buffer->ensure_inplace (buffer->len + num_glyphs))
1034         goto resize_and_retry;
1035
1036       hb_glyph_info_t *run_info = buffer->info + buffer->len;
1037
1038       /* Testing used to indicate that CTRunGetGlyphsPtr, etc (almost?) always
1039        * succeed, and so copying data to our own buffer will be rare.  Reports
1040        * have it that this changed in OS X 10.10 Yosemite, and NULL is returned
1041        * frequently.  At any rate, we can test that codepath by setting USE_PTR
1042        * to false. */
1043
1044 #define USE_PTR true
1045
1046 #define SCRATCH_SAVE() \
1047   unsigned int scratch_size_saved = scratch_size; \
1048   hb_buffer_t::scratch_buffer_t *scratch_saved = scratch
1049
1050 #define SCRATCH_RESTORE() \
1051   scratch_size = scratch_size_saved; \
1052   scratch = scratch_saved;
1053
1054       { /* Setup glyphs */
1055         SCRATCH_SAVE();
1056         const CGGlyph* glyphs = USE_PTR ? CTRunGetGlyphsPtr (run) : NULL;
1057         if (!glyphs) {
1058           ALLOCATE_ARRAY (CGGlyph, glyph_buf, num_glyphs, goto resize_and_retry);
1059           CTRunGetGlyphs (run, range_all, glyph_buf);
1060           glyphs = glyph_buf;
1061         }
1062         const CFIndex* string_indices = USE_PTR ? CTRunGetStringIndicesPtr (run) : NULL;
1063         if (!string_indices) {
1064           ALLOCATE_ARRAY (CFIndex, index_buf, num_glyphs, goto resize_and_retry);
1065           CTRunGetStringIndices (run, range_all, index_buf);
1066           string_indices = index_buf;
1067         }
1068         hb_glyph_info_t *info = run_info;
1069         for (unsigned int j = 0; j < num_glyphs; j++)
1070         {
1071           info->codepoint = glyphs[j];
1072           info->cluster = log_clusters[string_indices[j]];
1073           info++;
1074         }
1075         SCRATCH_RESTORE();
1076       }
1077       {
1078         /* Setup positions.
1079          * Note that CoreText does not return advances for glyphs.  As such,
1080          * for all but last glyph, we use the delta position to next glyph as
1081          * advance (in the advance direction only), and for last glyph we set
1082          * whatever is needed to make the whole run's advance add up. */
1083         SCRATCH_SAVE();
1084         const CGPoint* positions = USE_PTR ? CTRunGetPositionsPtr (run) : NULL;
1085         if (!positions) {
1086           ALLOCATE_ARRAY (CGPoint, position_buf, num_glyphs, goto resize_and_retry);
1087           CTRunGetPositions (run, range_all, position_buf);
1088           positions = position_buf;
1089         }
1090         hb_glyph_info_t *info = run_info;
1091         if (HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction))
1092         {
1093           hb_position_t x_offset = (positions[0].x - advances_so_far) * x_mult;
1094           for (unsigned int j = 0; j < num_glyphs; j++)
1095           {
1096             double advance;
1097             if (likely (j + 1 < num_glyphs))
1098               advance = positions[j + 1].x - positions[j].x;
1099             else /* last glyph */
1100               advance = run_advance - (positions[j].x - positions[0].x);
1101             info->mask = advance * x_mult;
1102             info->var1.i32 = x_offset;
1103             info->var2.i32 = positions[j].y * y_mult;
1104             info++;
1105           }
1106         }
1107         else
1108         {
1109           hb_position_t y_offset = (positions[0].y - advances_so_far) * y_mult;
1110           for (unsigned int j = 0; j < num_glyphs; j++)
1111           {
1112             double advance;
1113             if (likely (j + 1 < num_glyphs))
1114               advance = positions[j + 1].y - positions[j].y;
1115             else /* last glyph */
1116               advance = run_advance - (positions[j].y - positions[0].y);
1117             info->mask = advance * y_mult;
1118             info->var1.i32 = positions[j].x * x_mult;
1119             info->var2.i32 = y_offset;
1120             info++;
1121           }
1122         }
1123         SCRATCH_RESTORE();
1124         advances_so_far += run_advance;
1125       }
1126 #undef SCRATCH_RESTORE
1127 #undef SCRATCH_SAVE
1128 #undef USE_PTR
1129 #undef ALLOCATE_ARRAY
1130
1131       buffer->len += num_glyphs;
1132     }
1133
1134     /* Mac OS 10.6 doesn't have kCTTypesetterOptionForcedEmbeddingLevel,
1135      * or if it does, it doesn't resepct it.  So we get runs with wrong
1136      * directions.  As such, disable the assert...  It wouldn't crash, but
1137      * cursoring will be off...
1138      *
1139      * http://crbug.com/419769
1140      */
1141     if (0)
1142     {
1143       /* Make sure all runs had the expected direction. */
1144       bool backward = HB_DIRECTION_IS_BACKWARD (buffer->props.direction);
1145       assert (bool (status_and & kCTRunStatusRightToLeft) == backward);
1146       assert (bool (status_or  & kCTRunStatusRightToLeft) == backward);
1147     }
1148
1149     buffer->clear_positions ();
1150
1151     unsigned int count = buffer->len;
1152     hb_glyph_info_t *info = buffer->info;
1153     hb_glyph_position_t *pos = buffer->pos;
1154     if (HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction))
1155       for (unsigned int i = 0; i < count; i++)
1156       {
1157         pos->x_advance = info->mask;
1158         pos->x_offset = info->var1.i32;
1159         pos->y_offset = info->var2.i32;
1160         info++, pos++;
1161       }
1162     else
1163       for (unsigned int i = 0; i < count; i++)
1164       {
1165         pos->y_advance = info->mask;
1166         pos->x_offset = info->var1.i32;
1167         pos->y_offset = info->var2.i32;
1168         info++, pos++;
1169       }
1170
1171     /* Fix up clusters so that we never return out-of-order indices;
1172      * if core text has reordered glyphs, we'll merge them to the
1173      * beginning of the reordered cluster.  CoreText is nice enough
1174      * to tell us whenever it has produced nonmonotonic results...
1175      * Note that we assume the input clusters were nonmonotonic to
1176      * begin with.
1177      *
1178      * This does *not* mean we'll form the same clusters as Uniscribe
1179      * or the native OT backend, only that the cluster indices will be
1180      * monotonic in the output buffer. */
1181     if (count > 1 && (status_or & kCTRunStatusNonMonotonic))
1182     {
1183       hb_glyph_info_t *info = buffer->info;
1184       if (HB_DIRECTION_IS_FORWARD (buffer->props.direction))
1185       {
1186         unsigned int cluster = info[count - 1].cluster;
1187         for (unsigned int i = count - 1; i > 0; i--)
1188         {
1189           cluster = MIN (cluster, info[i - 1].cluster);
1190           info[i - 1].cluster = cluster;
1191         }
1192       }
1193       else
1194       {
1195         unsigned int cluster = info[0].cluster;
1196         for (unsigned int i = 1; i < count; i++)
1197         {
1198           cluster = MIN (cluster, info[i].cluster);
1199           info[i].cluster = cluster;
1200         }
1201       }
1202     }
1203   }
1204
1205 #undef FAIL
1206
1207 fail:
1208   if (string_ref)
1209     CFRelease (string_ref);
1210   if (line)
1211     CFRelease (line);
1212
1213   for (unsigned int i = 0; i < range_records.len; i++)
1214     if (range_records[i].font)
1215       CFRelease (range_records[i].font);
1216
1217   return ret;
1218 }
1219
1220
1221 /*
1222  * AAT shaper
1223  */
1224
1225 HB_SHAPER_DATA_ENSURE_DEFINE(coretext_aat, face)
1226 HB_SHAPER_DATA_ENSURE_DEFINE(coretext_aat, font)
1227
1228 /*
1229  * shaper face data
1230  */
1231
1232 struct hb_coretext_aat_shaper_face_data_t {};
1233
1234 hb_coretext_aat_shaper_face_data_t *
1235 _hb_coretext_aat_shaper_face_data_create (hb_face_t *face)
1236 {
1237   hb_blob_t *mort_blob = face->reference_table (HB_CORETEXT_TAG_MORT);
1238   /* Umm, we just reference the table to check whether it exists.
1239    * Maybe add better API for this? */
1240   if (!hb_blob_get_length (mort_blob))
1241   {
1242     hb_blob_destroy (mort_blob);
1243     mort_blob = face->reference_table (HB_CORETEXT_TAG_MORX);
1244     if (!hb_blob_get_length (mort_blob))
1245     {
1246       hb_blob_destroy (mort_blob);
1247       return NULL;
1248     }
1249   }
1250   hb_blob_destroy (mort_blob);
1251
1252   return hb_coretext_shaper_face_data_ensure (face) ? (hb_coretext_aat_shaper_face_data_t *) HB_SHAPER_DATA_SUCCEEDED : NULL;
1253 }
1254
1255 void
1256 _hb_coretext_aat_shaper_face_data_destroy (hb_coretext_aat_shaper_face_data_t *data HB_UNUSED)
1257 {
1258 }
1259
1260
1261 /*
1262  * shaper font data
1263  */
1264
1265 struct hb_coretext_aat_shaper_font_data_t {};
1266
1267 hb_coretext_aat_shaper_font_data_t *
1268 _hb_coretext_aat_shaper_font_data_create (hb_font_t *font)
1269 {
1270   return hb_coretext_shaper_font_data_ensure (font) ? (hb_coretext_aat_shaper_font_data_t *) HB_SHAPER_DATA_SUCCEEDED : NULL;
1271 }
1272
1273 void
1274 _hb_coretext_aat_shaper_font_data_destroy (hb_coretext_aat_shaper_font_data_t *data HB_UNUSED)
1275 {
1276 }
1277
1278
1279 /*
1280  * shaper shape_plan data
1281  */
1282
1283 struct hb_coretext_aat_shaper_shape_plan_data_t {};
1284
1285 hb_coretext_aat_shaper_shape_plan_data_t *
1286 _hb_coretext_aat_shaper_shape_plan_data_create (hb_shape_plan_t    *shape_plan HB_UNUSED,
1287                                              const hb_feature_t *user_features HB_UNUSED,
1288                                              unsigned int        num_user_features HB_UNUSED,
1289                                              const int          *coords HB_UNUSED,
1290                                              unsigned int        num_coords HB_UNUSED)
1291 {
1292   return (hb_coretext_aat_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
1293 }
1294
1295 void
1296 _hb_coretext_aat_shaper_shape_plan_data_destroy (hb_coretext_aat_shaper_shape_plan_data_t *data HB_UNUSED)
1297 {
1298 }
1299
1300
1301 /*
1302  * shaper
1303  */
1304
1305 hb_bool_t
1306 _hb_coretext_aat_shape (hb_shape_plan_t    *shape_plan,
1307                         hb_font_t          *font,
1308                         hb_buffer_t        *buffer,
1309                         const hb_feature_t *features,
1310                         unsigned int        num_features)
1311 {
1312   return _hb_coretext_shape (shape_plan, font, buffer, features, num_features);
1313 }