Roll HarfBuzz to 0.9.35

third_party/harfbuzz-ng/src/hb-ot-shape-complex-indic.cc

 /*
  * Copyright © 2011,2012  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.
@@ skipping 903 matching lines @@
           break;
         }
       break;
     }
 
   /* Handle beginning Ra */
   if (has_reph)
     info[start].indic_position() = POS_RA_TO_BECOME_REPH;
 
   /* For old-style Indic script tags, move the first post-base Halant after
-   * last consonant.  Only do this if there is *not* a Halant after last
-   * consonant.  Otherwise it becomes messy. */
-  if (indic_plan->is_old_spec) {
+   * last consonant.
+   *
+   * Reports suggest that in some scripts Uniscribe does this only if there
+   * is *not* a Halant after last consonant already (eg. Kannada), while it
+   * does it unconditionally in other scripts (eg. Malayalam).  We don't
+   * currently know about other scripts, so we single out Malayalam for now.
+   *
+   * Kannada test case:
+   * U+0C9A,U+0CCD,U+0C9A,U+0CCD
+   * With some versions of Lohit Kannada.
+   * https://bugs.freedesktop.org/show_bug.cgi?id=59118
+   *
+   * Malayalam test case:
+   * U+0D38,U+0D4D,U+0D31,U+0D4D,U+0D31,U+0D4D
+   * With lohit-ttf-20121122/Lohit-Malayalam.ttf
+   */
+  if (indic_plan->is_old_spec)
+  {
+    bool disallow_double_halants = buffer->props.script != HB_SCRIPT_MALAYALAM;
     for (unsigned int i = base + 1; i < end; i++)
-      if (info[i].indic_category() == OT_H) {
+      if (info[i].indic_category() == OT_H)
+      {
         unsigned int j;
         for (j = end - 1; j > i; j--)
-          if (is_consonant (info[j]) || info[j].indic_category() == OT_H)
+          if (is_consonant (info[j]) ||
+              (disallow_double_halants && info[j].indic_category() == OT_H))
             break;
         if (info[j].indic_category() != OT_H && j > i) {
           /* Move Halant to after last consonant. */
           hb_glyph_info_t t = info[i];
           memmove (&info[i], &info[i + 1], (j - i) * sizeof (info[0]));
           info[j] = t;
         }
         break;
       }
   }
@@ skipping 318 matching lines @@
     unsigned int syllable = buffer->cur().syllable();
     syllable_type_t syllable_type = (syllable_type_t) (syllable & 0x0F);
     if (unlikely (last_syllable != syllable && syllable_type == broken_cluster))
     {
       last_syllable = syllable;
 
       hb_glyph_info_t info = dottedcircle;
       info.cluster = buffer->cur().cluster;
       info.mask = buffer->cur().mask;
       info.syllable() = buffer->cur().syllable();
+      /* TODO Set glyph_props? */
 
       /* Insert dottedcircle after possible Repha. */
       while (buffer->idx < buffer->len &&
              last_syllable == buffer->cur().syllable() &&
              buffer->cur().indic_category() == OT_Repha)
         buffer->next_glyph ();
 
       buffer->output_info (info);
     }
     else
@@ skipping 576 matching lines @@
   data_create_indic,
   data_destroy_indic,
   NULL, /* preprocess_text */
   HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT,
   decompose_indic,
   compose_indic,
   setup_masks_indic,
   HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE,
   false, /* fallback_position */
 };