Update harfbuzz-ng to 0.9.24

third_party/harfbuzz-ng/src/hb-coretext.cc

 /*
- * Copyright © 2012  Mozilla Foundation.
- * Copyright © 2012  Google, Inc.
+ * Copyright © 2012,2013  Mozilla Foundation.
+ * Copyright © 2012,2013  Google, Inc.
  *
  *  This is part of HarfBuzz, a text shaping library.
  *
  * Permission is hereby granted, without written agreement and without
  * license or royalty fees, to use, copy, modify, and distribute this
  * software and its documentation for any purpose, provided that the
  * above copyright notice and the following two paragraphs appear in
  * all copies of this software.
  *
  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
@@ skipping 149 matching lines @@
   if (unlikely (!hb_coretext_shaper_font_data_ensure (font))) return NULL;
   hb_coretext_shaper_font_data_t *font_data = HB_SHAPER_DATA_GET (font);
   return font_data->ct_font;
 }
 
 
 /*
  * shaper
  */
 
+struct feature_record_t {
+  unsigned int feature;
+  unsigned int setting;
+};
+
+struct active_feature_t {
+  feature_record_t rec;
+  unsigned int order;
+
+  static int cmp (const active_feature_t *a, const active_feature_t *b) {
+    return a->rec.feature < b->rec.feature ? -1 : a->rec.feature > b->rec.feature ? 1 :
+           a->order < b->order ? -1 : a->order > b->order ? 1 :
+           a->rec.setting < b->rec.setting ? -1 : a->rec.setting > b->rec.setting ? 1 :
+           0;
+  }
+  bool operator== (const active_feature_t *f) {
+    return cmp (this, f) == 0;
+  }
+};
+
+struct feature_event_t {
+  unsigned int index;
+  bool start;
+  active_feature_t feature;
+
+  static int cmp (const feature_event_t *a, const feature_event_t *b) {
+    return a->index < b->index ? -1 : a->index > b->index ? 1 :
+           a->start < b->start ? -1 : a->start > b->start ? 1 :
+           active_feature_t::cmp (&a->feature, &b->feature);
+  }
+};
+
+struct range_record_t {
+  CTFontRef font;
+  unsigned int index_first; /* == start */
+  unsigned int index_last;  /* == end - 1 */
+};
+
+
+/* The following enum members are added in OS X 10.8. */
+#define kAltHalfWidthTextSelector               6
+#define kAltProportionalTextSelector            5
+#define kAlternateHorizKanaOffSelector          1
+#define kAlternateHorizKanaOnSelector           0
+#define kAlternateKanaType                      34
+#define kAlternateVertKanaOffSelector           3
+#define kAlternateVertKanaOnSelector            2
+#define kCaseSensitiveLayoutOffSelector         1
+#define kCaseSensitiveLayoutOnSelector          0
+#define kCaseSensitiveLayoutType                33
+#define kCaseSensitiveSpacingOffSelector        3
+#define kCaseSensitiveSpacingOnSelector         2
+#define kContextualAlternatesOffSelector        1
+#define kContextualAlternatesOnSelector         0
+#define kContextualAlternatesType               36
+#define kContextualLigaturesOffSelector         19
+#define kContextualLigaturesOnSelector          18
+#define kContextualSwashAlternatesOffSelector   5
+#define kContextualSwashAlternatesOnSelector    4
+#define kDefaultLowerCaseSelector               0
+#define kDefaultUpperCaseSelector               0
+#define kHistoricalLigaturesOffSelector         21
+#define kHistoricalLigaturesOnSelector          20
+#define kHojoCharactersSelector                 12
+#define kJIS2004CharactersSelector              11
+#define kLowerCasePetiteCapsSelector            2
+#define kLowerCaseSmallCapsSelector             1
+#define kLowerCaseType                          37
+#define kMathematicalGreekOffSelector           11
+#define kMathematicalGreekOnSelector            10
+#define kNLCCharactersSelector                  13
+#define kQuarterWidthTextSelector               4
+#define kScientificInferiorsSelector            4
+#define kStylisticAltEightOffSelector           17
+#define kStylisticAltEightOnSelector            16
+#define kStylisticAltEighteenOffSelector        37
+#define kStylisticAltEighteenOnSelector         36
+#define kStylisticAltElevenOffSelector          23
+#define kStylisticAltElevenOnSelector           22
+#define kStylisticAltFifteenOffSelector         31
+#define kStylisticAltFifteenOnSelector          30
+#define kStylisticAltFiveOffSelector            11
+#define kStylisticAltFiveOnSelector             10
+#define kStylisticAltFourOffSelector            9
+#define kStylisticAltFourOnSelector             8
+#define kStylisticAltFourteenOffSelector        29
+#define kStylisticAltFourteenOnSelector         28
+#define kStylisticAltNineOffSelector            19
+#define kStylisticAltNineOnSelector             18
+#define kStylisticAltNineteenOffSelector        39
+#define kStylisticAltNineteenOnSelector         38
+#define kStylisticAltOneOffSelector             3
+#define kStylisticAltOneOnSelector              2
+#define kStylisticAltSevenOffSelector           15
+#define kStylisticAltSevenOnSelector            14
+#define kStylisticAltSeventeenOffSelector       35
+#define kStylisticAltSeventeenOnSelector        34
+#define kStylisticAltSixOffSelector             13
+#define kStylisticAltSixOnSelector              12
+#define kStylisticAltSixteenOffSelector         33
+#define kStylisticAltSixteenOnSelector          32
+#define kStylisticAltTenOffSelector             21
+#define kStylisticAltTenOnSelector              20
+#define kStylisticAltThirteenOffSelector        27
+#define kStylisticAltThirteenOnSelector         26
+#define kStylisticAltThreeOffSelector           7
+#define kStylisticAltThreeOnSelector            6
+#define kStylisticAltTwelveOffSelector          25
+#define kStylisticAltTwelveOnSelector           24
+#define kStylisticAltTwentyOffSelector          41
+#define kStylisticAltTwentyOnSelector           40
+#define kStylisticAltTwoOffSelector             5
+#define kStylisticAltTwoOnSelector              4
+#define kStylisticAlternativesType              35
+#define kSwashAlternatesOffSelector             3
+#define kSwashAlternatesOnSelector              2
+#define kThirdWidthTextSelector                 3
+#define kTraditionalNamesCharactersSelector     14
+#define kUpperCasePetiteCapsSelector            2
+#define kUpperCaseSmallCapsSelector             1
+#define kUpperCaseType                          38
+
+/* Table data courtesy of Apple. */
+struct feature_mapping_t {
+    FourCharCode otFeatureTag;
+    uint16_t aatFeatureType;
+    uint16_t selectorToEnable;
+    uint16_t selectorToDisable;
+} feature_mappings[] = {
+    { 'c2pc',   kUpperCaseType,             kUpperCasePetiteCapsSelector,           kDefaultUpperCaseSelector },
+    { 'c2sc',   kUpperCaseType,             kUpperCaseSmallCapsSelector,            kDefaultUpperCaseSelector },
+    { 'calt',   kContextualAlternatesType,  kContextualAlternatesOnSelector,        kContextualAlternatesOffSelector },
+    { 'case',   kCaseSensitiveLayoutType,   kCaseSensitiveLayoutOnSelector,         kCaseSensitiveLayoutOffSelector },
+    { 'clig',   kLigaturesType,             kContextualLigaturesOnSelector,         kContextualLigaturesOffSelector },
+    { 'cpsp',   kCaseSensitiveLayoutType,   kCaseSensitiveSpacingOnSelector,        kCaseSensitiveSpacingOffSelector },
+    { 'cswh',   kContextualAlternatesType,  kContextualSwashAlternatesOnSelector,   kContextualSwashAlternatesOffSelector },
+    { 'dlig',   kLigaturesType,             kRareLigaturesOnSelector,               kRareLigaturesOffSelector },
+    { 'expt',   kCharacterShapeType,        kExpertCharactersSelector,              16 },
+    { 'frac',   kFractionsType,             kDiagonalFractionsSelector,             kNoFractionsSelector },
+    { 'fwid',   kTextSpacingType,           kMonospacedTextSelector,                7 },
+    { 'halt',   kTextSpacingType,           kAltHalfWidthTextSelector,              7 },
+    { 'hist',   kLigaturesType,             kHistoricalLigaturesOnSelector,         kHistoricalLigaturesOffSelector },
+    { 'hkna',   kAlternateKanaType,         kAlternateHorizKanaOnSelector,          kAlternateHorizKanaOffSelector, },
+    { 'hlig',   kLigaturesType,             kHistoricalLigaturesOnSelector,         kHistoricalLigaturesOffSelector },
+    { 'hngl',   kTransliterationType,       kHanjaToHangulSelector,                 kNoTransliterationSelector },
+    { 'hojo',   kCharacterShapeType,        kHojoCharactersSelector,                16 },
+    { 'hwid',   kTextSpacingType,           kHalfWidthTextSelector,                 7 },
+    { 'ital',   kItalicCJKRomanType,        kCJKItalicRomanOnSelector,              kCJKItalicRomanOffSelector },
+    { 'jp04',   kCharacterShapeType,        kJIS2004CharactersSelector,             16 },
+    { 'jp78',   kCharacterShapeType,        kJIS1978CharactersSelector,             16 },
+    { 'jp83',   kCharacterShapeType,        kJIS1983CharactersSelector,             16 },
+    { 'jp90',   kCharacterShapeType,        kJIS1990CharactersSelector,             16 },
+    { 'liga',   kLigaturesType,             kCommonLigaturesOnSelector,             kCommonLigaturesOffSelector },
+    { 'lnum',   kNumberCaseType,            kUpperCaseNumbersSelector,              2 },
+    { 'mgrk',   kMathematicalExtrasType,    kMathematicalGreekOnSelector,           kMathematicalGreekOffSelector },
+    { 'nlck',   kCharacterShapeType,        kNLCCharactersSelector,                 16 },
+    { 'onum',   kNumberCaseType,            kLowerCaseNumbersSelector,              2 },
+    { 'ordn',   kVerticalPositionType,      kOrdinalsSelector,                      kNormalPositionSelector },
+    { 'palt',   kTextSpacingType,           kAltProportionalTextSelector,           7 },
+    { 'pcap',   kLowerCaseType,             kLowerCasePetiteCapsSelector,           kDefaultLowerCaseSelector },
+    { 'pkna',   kTextSpacingType,           kProportionalTextSelector,              7 },
+    { 'pnum',   kNumberSpacingType,         kProportionalNumbersSelector,           4 },
+    { 'pwid',   kTextSpacingType,           kProportionalTextSelector,              7 },
+    { 'qwid',   kTextSpacingType,           kQuarterWidthTextSelector,              7 },
+    { 'ruby',   kRubyKanaType,              kRubyKanaOnSelector,                    kRubyKanaOffSelector },
+    { 'sinf',   kVerticalPositionType,      kScientificInferiorsSelector,           kNormalPositionSelector },
+    { 'smcp',   kLowerCaseType,             kLowerCaseSmallCapsSelector,            kDefaultLowerCaseSelector },
+    { 'smpl',   kCharacterShapeType,        kSimplifiedCharactersSelector,          16 },
+    { 'ss01',   kStylisticAlternativesType, kStylisticAltOneOnSelector,             kStylisticAltOneOffSelector },
+    { 'ss02',   kStylisticAlternativesType, kStylisticAltTwoOnSelector,             kStylisticAltTwoOffSelector },
+    { 'ss03',   kStylisticAlternativesType, kStylisticAltThreeOnSelector,           kStylisticAltThreeOffSelector },
+    { 'ss04',   kStylisticAlternativesType, kStylisticAltFourOnSelector,            kStylisticAltFourOffSelector },
+    { 'ss05',   kStylisticAlternativesType, kStylisticAltFiveOnSelector,            kStylisticAltFiveOffSelector },
+    { 'ss06',   kStylisticAlternativesType, kStylisticAltSixOnSelector,             kStylisticAltSixOffSelector },
+    { 'ss07',   kStylisticAlternativesType, kStylisticAltSevenOnSelector,           kStylisticAltSevenOffSelector },
+    { 'ss08',   kStylisticAlternativesType, kStylisticAltEightOnSelector,           kStylisticAltEightOffSelector },
+    { 'ss09',   kStylisticAlternativesType, kStylisticAltNineOnSelector,            kStylisticAltNineOffSelector },
+    { 'ss10',   kStylisticAlternativesType, kStylisticAltTenOnSelector,             kStylisticAltTenOffSelector },
+    { 'ss11',   kStylisticAlternativesType, kStylisticAltElevenOnSelector,          kStylisticAltElevenOffSelector },
+    { 'ss12',   kStylisticAlternativesType, kStylisticAltTwelveOnSelector,          kStylisticAltTwelveOffSelector },
+    { 'ss13',   kStylisticAlternativesType, kStylisticAltThirteenOnSelector,        kStylisticAltThirteenOffSelector },
+    { 'ss14',   kStylisticAlternativesType, kStylisticAltFourteenOnSelector,        kStylisticAltFourteenOffSelector },
+    { 'ss15',   kStylisticAlternativesType, kStylisticAltFifteenOnSelector,         kStylisticAltFifteenOffSelector },
+    { 'ss16',   kStylisticAlternativesType, kStylisticAltSixteenOnSelector,         kStylisticAltSixteenOffSelector },
+    { 'ss17',   kStylisticAlternativesType, kStylisticAltSeventeenOnSelector,       kStylisticAltSeventeenOffSelector },
+    { 'ss18',   kStylisticAlternativesType, kStylisticAltEighteenOnSelector,        kStylisticAltEighteenOffSelector },
+    { 'ss19',   kStylisticAlternativesType, kStylisticAltNineteenOnSelector,        kStylisticAltNineteenOffSelector },
+    { 'ss20',   kStylisticAlternativesType, kStylisticAltTwentyOnSelector,          kStylisticAltTwentyOffSelector },
+    { 'subs',   kVerticalPositionType,      kInferiorsSelector,                     kNormalPositionSelector },
+    { 'sups',   kVerticalPositionType,      kSuperiorsSelector,                     kNormalPositionSelector },
+    { 'swsh',   kContextualAlternatesType,  kSwashAlternatesOnSelector,             kSwashAlternatesOffSelector },
+    { 'titl',   kStyleOptionsType,          kTitlingCapsSelector,                   kNoStyleOptionsSelector },
+    { 'tnam',   kCharacterShapeType,        kTraditionalNamesCharactersSelector,    16 },
+    { 'tnum',   kNumberSpacingType,         kMonospacedNumbersSelector,             4 },
+    { 'trad',   kCharacterShapeType,        kTraditionalCharactersSelector,         16 },
+    { 'twid',   kTextSpacingType,           kThirdWidthTextSelector,                7 },
+    { 'unic',   kLetterCaseType,            14,                                     15 },
+    { 'valt',   kTextSpacingType,           kAltProportionalTextSelector,           7 },
+    { 'vert',   kVerticalSubstitutionType,  kSubstituteVerticalFormsOnSelector,     kSubstituteVerticalFormsOffSelector },
+    { 'vhal',   kTextSpacingType,           kAltHalfWidthTextSelector,              7 },
+    { 'vkna',   kAlternateKanaType,         kAlternateVertKanaOnSelector,           kAlternateVertKanaOffSelector },
+    { 'vpal',   kTextSpacingType,           kAltProportionalTextSelector,           7 },
+    { 'vrt2',   kVerticalSubstitutionType,  kSubstituteVerticalFormsOnSelector,     kSubstituteVerticalFormsOffSelector },
+    { 'zero',   kTypographicExtrasType,     kSlashedZeroOnSelector,                 kSlashedZeroOffSelector },
+};
+
+static int
+_hb_feature_mapping_cmp (const void *key_, const void *entry_)
+{
+  unsigned int key = * (unsigned int *) key_;
+  const feature_mapping_t * entry = (const feature_mapping_t *) entry_;
+  return key < entry->otFeatureTag ? -1 :
+         key > entry->otFeatureTag ? 1 :
+         0;
+}
+
 hb_bool_t
 _hb_coretext_shape (hb_shape_plan_t    *shape_plan,
                     hb_font_t          *font,
                     hb_buffer_t        *buffer,
                     const hb_feature_t *features,
                     unsigned int        num_features)
 {
   hb_face_t *face = font->face;
-  hb_coretext_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
   hb_coretext_shaper_font_data_t *font_data = HB_SHAPER_DATA_GET (font);
 
+  /*
+   * Set up features.
+   * (copied + modified from code from hb-uniscribe.cc)
+   */
+  hb_auto_array_t<feature_record_t> feature_records;
+  hb_auto_array_t<range_record_t> range_records;
+  if (num_features)
+  {
+    /* Sort features by start/end events. */
+    hb_auto_array_t<feature_event_t> feature_events;
+    for (unsigned int i = 0; i < num_features; i++)
+    {
+      const feature_mapping_t * mapping = (const feature_mapping_t *) bsearch (&features[i].tag,
+                                                                               feature_mappings,
+                                                                               ARRAY_LENGTH (feature_mappings),
+                                                                               sizeof (feature_mappings[0]),
+                                                                               _hb_feature_mapping_cmp);
+      if (!mapping)
+        continue;
+
+      active_feature_t feature;
+      feature.rec.feature = mapping->aatFeatureType;
+      feature.rec.setting = features[i].value ? mapping->selectorToEnable : mapping->selectorToDisable;
+      feature.order = i;
+
+      feature_event_t *event;
+
+      event = feature_events.push ();
+      if (unlikely (!event))
+        goto fail_features;
+      event->index = features[i].start;
+      event->start = true;
+      event->feature = feature;
+
+      event = feature_events.push ();
+      if (unlikely (!event))
+        goto fail_features;
+      event->index = features[i].end;
+      event->start = false;
+      event->feature = feature;
+    }
+    feature_events.sort ();
+    /* Add a strategic final event. */
+    {
+      active_feature_t feature;
+      feature.rec.feature = HB_TAG_NONE;
+      feature.rec.setting = 0;
+      feature.order = num_features + 1;
+
+      feature_event_t *event = feature_events.push ();
+      if (unlikely (!event))
+        goto fail_features;
+      event->index = 0; /* This value does magic. */
+      event->start = false;
+      event->feature = feature;
+    }
+
+    /* Scan events and save features for each range. */
+    hb_auto_array_t<active_feature_t> active_features;
+    unsigned int last_index = 0;
+    for (unsigned int i = 0; i < feature_events.len; i++)
+    {
+      feature_event_t *event = &feature_events[i];
+
+      if (event->index != last_index)
+      {
+        /* Save a snapshot of active features and the range. */
+        range_record_t *range = range_records.push ();
+        if (unlikely (!range))
+          goto fail_features;
+
+        unsigned int offset = feature_records.len;
+
+        if (active_features.len)
+        {
+          CFMutableArrayRef features_array = CFArrayCreateMutable(kCFAllocatorDefault, 0, &kCFTypeArrayCallBacks);
+
+          /* TODO sort and resolve conflicting features? */
+          /* active_features.sort (); */
+          for (unsigned int j = 0; j < active_features.len; j++)
+          {
+            CFStringRef keys[2] = {
+              kCTFontFeatureTypeIdentifierKey,
+              kCTFontFeatureSelectorIdentifierKey
+            };
+            CFNumberRef values[2] = {
+              CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &active_features[j].rec.feature),
+              CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &active_features[j].rec.setting)
+            };
+            CFDictionaryRef dict = CFDictionaryCreate (kCFAllocatorDefault,
+                                                       (const void **) keys,
+                                                       (const void **) values,
+                                                       2,
+                                                       &kCFTypeDictionaryKeyCallBacks,
+                                                       &kCFTypeDictionaryValueCallBacks);
+            CFRelease (values[0]);
+            CFRelease (values[1]);
+
+            CFArrayAppendValue (features_array, dict);
+            CFRelease (dict);
+
+          }
+
+          CFDictionaryRef attributes = CFDictionaryCreate (kCFAllocatorDefault,
+                                                           (const void **) &kCTFontFeatureSettingsAttribute,
+                                                           (const void **) &features_array,
+                                                           1,
+                                                           &kCFTypeDictionaryKeyCallBacks,
+                                                           &kCFTypeDictionaryValueCallBacks);
+          CFRelease (features_array);
+
+          CTFontDescriptorRef font_desc = CTFontDescriptorCreateWithAttributes (attributes);
+          CFRelease (attributes);
+
+          range->font = CTFontCreateCopyWithAttributes (font_data->ct_font, 0.0, NULL, font_desc);
+
+          CFRelease (font_desc);
+        }
+        else
+        {
+          range->font = NULL;
+        }
+
+        range->index_first = last_index;
+        range->index_last  = event->index - 1;
+
+        last_index = event->index;
+      }
+
+      if (event->start) {
+        active_feature_t *feature = active_features.push ();
+        if (unlikely (!feature))
+          goto fail_features;
+        *feature = event->feature;
+      } else {
+        active_feature_t *feature = active_features.find (&event->feature);
+        if (feature)
+          active_features.remove (feature - active_features.array);
+      }
+    }
+
+    if (!range_records.len) /* No active feature found. */
+      goto fail_features;
+  }
+  else
+  {
+  fail_features:
+    num_features = 0;
+  }
+
 #define FAIL(...) \
   HB_STMT_START { \
     DEBUG_MSG (CORETEXT, NULL, __VA_ARGS__); \
     return false; \
   } HB_STMT_END;
 
   unsigned int scratch_size;
-  char *scratch = (char *) buffer->get_scratch_buffer (&scratch_size);
+  hb_buffer_t::scratch_buffer_t *scratch = buffer->get_scratch_buffer (&scratch_size);
+
+#define ALLOCATE_ARRAY(Type, name, len) \
+  Type *name = (Type *) scratch; \
+  { \
+    unsigned int _consumed = DIV_CEIL ((len) * sizeof (Type), sizeof (*scratch)); \
+    assert (_consumed <= scratch_size); \
+    scratch += _consumed; \
+    scratch_size -= _consumed; \
+  }
 
 #define utf16_index() var1.u32
 
-  UniChar *pchars = (UniChar *) scratch;
+  ALLOCATE_ARRAY (UniChar, pchars, buffer->len * 2);
+
   unsigned int chars_len = 0;
   for (unsigned int i = 0; i < buffer->len; i++) {
     hb_codepoint_t c = buffer->info[i].codepoint;
     buffer->info[i].utf16_index() = chars_len;
     if (likely (c < 0x10000))
       pchars[chars_len++] = c;
     else if (unlikely (c >= 0x110000))
       pchars[chars_len++] = 0xFFFD;
     else {
       pchars[chars_len++] = 0xD800 + ((c - 0x10000) >> 10);
       pchars[chars_len++] = 0xDC00 + ((c - 0x10000) & ((1 << 10) - 1));
     }
   }
 
 #undef utf16_index
 
-  CFStringRef string_ref = CFStringCreateWithCharactersNoCopy (kCFAllocatorDefault,
+  CFStringRef string_ref = CFStringCreateWithCharactersNoCopy (NULL,
                                                                pchars, chars_len,
                                                                kCFAllocatorNull);
 
-  CFDictionaryRef attrs = CFDictionaryCreate (kCFAllocatorDefault,
-                                              (const void**) &kCTFontAttributeName,
-                                              (const void**) &font_data->ct_font,
-                                              1, /* count of attributes */
-                                              &kCFTypeDictionaryKeyCallBacks,
-                                              &kCFTypeDictionaryValueCallBacks);
+  CFMutableAttributedStringRef attr_string = CFAttributedStringCreateMutable (NULL, chars_len);
+  CFAttributedStringReplaceString (attr_string, CFRangeMake (0, 0), string_ref);
+  CFRelease (string_ref);
+  CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
+                                  kCTFontAttributeName, font_data->ct_font);
 
-  /* TODO: support features */
+  if (num_features)
+  {
+    ALLOCATE_ARRAY (unsigned int, log_clusters, chars_len);
 
-  CFAttributedStringRef attr_string = CFAttributedStringCreate (kCFAllocatorDefault, string_ref, attrs);
-  CFRelease (string_ref);
-  CFRelease (attrs);
+    /* Need log_clusters to assign features. */
+    chars_len = 0;
+    for (unsigned int i = 0; i < buffer->len; i++)
+    {
+      hb_codepoint_t c = buffer->info[i].codepoint;
+      unsigned int cluster = buffer->info[i].cluster;
+      log_clusters[chars_len++] = cluster;
+      if (c >= 0x10000 && c < 0x110000)
+        log_clusters[chars_len++] = cluster; /* Surrogates. */
+    }
+
+    unsigned int start = 0;
+    range_record_t *last_range = &range_records[0];
+    for (unsigned int k = 0; k < chars_len; k++)
+    {
+      range_record_t *range = last_range;
+      while (log_clusters[k] < range->index_first)
+        range--;
+      while (log_clusters[k] > range->index_last)
+        range++;
+      if (range != last_range)
+      {
+        if (last_range->font)
+          CFAttributedStringSetAttribute (attr_string, CFRangeMake (start, k - start),
+                                          kCTFontAttributeName, last_range->font);
+
+        start = k;
+      }
+
+      last_range = range;
+    }
+    if (start != chars_len && last_range->font)
+      CFAttributedStringSetAttribute (attr_string, CFRangeMake (start, chars_len - start - 1),
+                                      kCTFontAttributeName, last_range->font);
+
+    for (unsigned int i = 0; i < range_records.len; i++)
+      if (range_records[i].font)
+        CFRelease (range_records[i].font);
+  }
 
   CTLineRef line = CTLineCreateWithAttributedString (attr_string);
   CFRelease (attr_string);
 
   CFArrayRef glyph_runs = CTLineGetGlyphRuns (line);
   unsigned int num_runs = CFArrayGetCount (glyph_runs);
 
-  bool success = true;
   buffer->len = 0;
 
   const CFRange range_all = CFRangeMake (0, 0);
 
   for (unsigned int i = 0; i < num_runs; i++) {
     CTRunRef run = (CTRunRef) CFArrayGetValueAtIndex (glyph_runs, i);
 
     unsigned int num_glyphs = CTRunGetGlyphCount (run);
     if (num_glyphs == 0)
       continue;
 
     buffer->ensure (buffer->len + num_glyphs);
 
-    /* Testing indicates that CTRunGetGlyphsPtr (almost?) always succeeds,
-     * and so copying data to our own buffer with CTRunGetGlyphs will be
-     * extremely rare. */
+    scratch = buffer->get_scratch_buffer (&scratch_size);
 
-    unsigned int scratch_size;
-    char *scratch = (char *) buffer->get_scratch_buffer (&scratch_size);
-
-#define ALLOCATE_ARRAY(Type, name, len) \
-  Type *name = (Type *) scratch; \
-  scratch += (len) * sizeof ((name)[0]); \
-  scratch_size -= (len) * sizeof ((name)[0]);
+    /* Testing indicates that CTRunGetGlyphsPtr, etc (almost?) always
+     * succeed, and so copying data to our own buffer will be rare. */
 
     const CGGlyph* glyphs = CTRunGetGlyphsPtr (run);
     if (!glyphs) {
       ALLOCATE_ARRAY (CGGlyph, glyph_buf, num_glyphs);
       CTRunGetGlyphs (run, range_all, glyph_buf);
       glyphs = glyph_buf;
     }
 
     const CGPoint* positions = CTRunGetPositionsPtr (run);
     if (!positions) {
@@ skipping 10 matching lines @@
     }
 
 #undef ALLOCATE_ARRAY
 
     double run_width = CTRunGetTypographicBounds (run, range_all, NULL, NULL, NULL);
 
     for (unsigned int j = 0; j < num_glyphs; j++) {
       double advance = (j + 1 < num_glyphs ? positions[j + 1].x : positions[0].x + run_width) - positions[j].x;
 
       hb_glyph_info_t *info = &buffer->info[buffer->len];
-      hb_glyph_position_t *pos = &buffer->pos[buffer->len];
 
       info->codepoint = glyphs[j];
       info->cluster = string_indices[j];
 
       /* Currently, we do all x-positioning by setting the advance, we never use x-offset. */
       info->mask = advance;
       info->var1.u32 = 0;
       info->var2.u32 = positions[j].y;
 
       buffer->len++;
@@ skipping 43 matching lines @@
           if (buffer->info[j - 1].cluster < curr_cluster)
             buffer->info[j - 1].cluster = curr_cluster;
           else
             break;
         }
       }
       prev_cluster = curr_cluster;
     }
   }
 
+  CFRelease (line);
+
   return true;
 }