Update Harfbuzz to version 6.0.0

Note: This requires an update to the tst_qtextlayout test, because
the test assumed that the Arabic string would always yield a run
of two glyphs. This was a side effect of how Harfbuzz handled
Qt's test font, which has zero font tables and cannot be used for
shaping. With the Harfbuzz update, the Arabic text here yields a
single cluster instead, which actually makes more sense, so the
test has been made a bit more robust to support both cases.

Pick-to: 6.2 6.5
Task-number: QTBUG-110338
Change-Id: I93d4cf8e3046dc93224e144d4c81d86bef4918d1
Reviewed-by: Lars Knoll <lars@knoll.priv.no>
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

1 files changed, 14 insertions, 3 deletions

diff --git a/src/3rdparty/harfbuzz-ng/src/OT/Layout/GSUB/AlternateSubst.hh b/src/3rdparty/harfbuzz-ng/src/OT/Layout/GSUB/AlternateSubst.hh
index e5d999261f..9d7cd6fddf 100644
--- a/src/3rdparty/harfbuzz-ng/src/OT/Layout/GSUB/AlternateSubst.hh
+++ b/src/3rdparty/harfbuzz-ng/src/OT/Layout/GSUB/AlternateSubst.hh
@@ -6,14 +6,17 @@
 
 namespace OT {
 namespace Layout {
-namespace GSUB {
+namespace GSUB_impl {
 
 struct AlternateSubst
 {
   protected:
   union {
-  HBUINT16              format;         /* Format identifier */
-  AlternateSubstFormat1 format1;
+  HBUINT16				format;         /* Format identifier */
+  AlternateSubstFormat1_2<SmallTypes>	format1;
+#ifndef HB_NO_BEYOND_64K
+  AlternateSubstFormat1_2<MediumTypes>	format2;
+#endif
   } u;
   public:
 
@@ -24,10 +27,15 @@ struct AlternateSubst
     if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ());
     switch (u.format) {
     case 1: return_trace (c->dispatch (u.format1, std::forward<Ts> (ds)...));
+#ifndef HB_NO_BEYOND_64K
+    case 2: return_trace (c->dispatch (u.format2, std::forward<Ts> (ds)...));
+#endif
     default:return_trace (c->default_return_value ());
     }
   }
 
+  /* TODO This function is unused and not updated to 24bit GIDs. Should be done by using
+   * iterators. While at it perhaps using iterator of arrays of hb_codepoint_t instead. */
   bool serialize (hb_serialize_context_t *c,
                   hb_sorted_array_t<const HBGlyphID16> glyphs,
                   hb_array_t<const unsigned int> alternate_len_list,
@@ -42,6 +50,9 @@ struct AlternateSubst
     default:return_trace (false);
     }
   }
+
+  /* TODO subset() should choose format. */
+
 };
 
 }