Roll HarfBuzz to 0.9.32

third_party/harfbuzz-ng/src/hb-ot-layout-gsub-table.hh

 /*
  * Copyright © 2007,2008,2009,2010  Red Hat, Inc.
  * Copyright © 2010,2012,2013  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
@@ skipping 26 matching lines @@
 
 struct SingleSubstFormat1
 {
   inline void closure (hb_closure_context_t *c) const
   {
     TRACE_CLOSURE (this);
     Coverage::Iter iter;
     for (iter.init (this+coverage); iter.more (); iter.next ()) {
       hb_codepoint_t glyph_id = iter.get_glyph ();
       if (c->glyphs->has (glyph_id))
-        c->glyphs->add ((glyph_id + deltaGlyphID) & 0xFFFF);
+        c->glyphs->add ((glyph_id + deltaGlyphID) & 0xFFFFu);
     }
   }
 
   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
   {
     TRACE_COLLECT_GLYPHS (this);
     Coverage::Iter iter;
     for (iter.init (this+coverage); iter.more (); iter.next ()) {
       hb_codepoint_t glyph_id = iter.get_glyph ();
       c->input->add (glyph_id);
-      c->output->add ((glyph_id + deltaGlyphID) & 0xFFFF);
+      c->output->add ((glyph_id + deltaGlyphID) & 0xFFFFu);
     }
   }
 
   inline const Coverage &get_coverage (void) const
   {
     return this+coverage;
   }
 
   inline bool would_apply (hb_would_apply_context_t *c) const
   {
     TRACE_WOULD_APPLY (this);
     return TRACE_RETURN (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED);
   }
 
   inline bool apply (hb_apply_context_t *c) const
   {
     TRACE_APPLY (this);
     hb_codepoint_t glyph_id = c->buffer->cur().codepoint;
     unsigned int index = (this+coverage).get_coverage (glyph_id);
     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
 
     /* According to the Adobe Annotated OpenType Suite, result is always
      * limited to 16bit. */
-    glyph_id = (glyph_id + deltaGlyphID) & 0xFFFF;
+    glyph_id = (glyph_id + deltaGlyphID) & 0xFFFFu;
     c->replace_glyph (glyph_id);
 
     return TRACE_RETURN (true);
   }
 
   inline bool serialize (hb_serialize_context_t *c,
                          Supplier<GlyphID> &glyphs,
                          unsigned int num_glyphs,
                          int delta)
   {
@@ skipping 170 matching lines @@
   {
     TRACE_COLLECT_GLYPHS (this);
     unsigned int count = substitute.len;
     for (unsigned int i = 0; i < count; i++)
       c->output->add (substitute[i]);
   }
 
   inline bool apply (hb_apply_context_t *c) const
   {
     TRACE_APPLY (this);
-    if (unlikely (!substitute.len)) return TRACE_RETURN (false);
+    unsigned int count = substitute.len;
+
+    /* TODO:
+     * Testing shows that Uniscribe actually allows zero-len susbstitute,
+     * which essentially deletes a glyph.  We don't allow for now.  It
+     * can be confusing to the client since the cluster from the deleted
+     * glyph won't be merged with any output cluster...  Also, currently
+     * buffer->move_to() makes assumptions about this too.  Perhaps fix
+     * in the future after figuring out what to do with the clusters.
+     */
+    if (unlikely (!count)) return TRACE_RETURN (false);
+
+    /* Special-case to make it in-place and not consider this
+     * as a "multiplied" substitution. */
+    if (unlikely (count == 1))
+    {
+      c->replace_glyph (substitute.array[0]);
+      return TRACE_RETURN (true);
+    }
 
     unsigned int klass = _hb_glyph_info_is_ligature (&c->buffer->cur()) ?
                          HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH : 0;
-    unsigned int count = substitute.len;
-    if (count == 1) /* Special-case to make it in-place. */
-    {
-      c->replace_glyph (substitute.array[0]);
+
+    for (unsigned int i = 0; i < count; i++) {
+      _hb_glyph_info_set_lig_props_for_component (&c->buffer->cur(), i);
+      c->output_glyph_for_component (substitute.array[i], klass);
     }
-    else
-    {
-      for (unsigned int i = 0; i < count; i++) {
-        _hb_glyph_info_set_lig_props_for_component (&c->buffer->cur(), i);
-        c->output_glyph (substitute.array[i], klass);
-      }
-      c->buffer->skip_glyph ();
-    }
+    c->buffer->skip_glyph ();
 
     return TRACE_RETURN (true);
   }
 
   inline bool serialize (hb_serialize_context_t *c,
                          Supplier<GlyphID> &glyphs,
                          unsigned int num_glyphs)
   {
     TRACE_SERIALIZE (this);
     if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
@@ skipping 317 matching lines @@
       if (likely (c->glyphs[i] != component[i]))
         return TRACE_RETURN (false);
 
     return TRACE_RETURN (true);
   }
 
   inline bool apply (hb_apply_context_t *c) const
   {
     TRACE_APPLY (this);
     unsigned int count = component.len;
-    if (unlikely (count < 1)) return TRACE_RETURN (false);
+
+    if (unlikely (!count)) return TRACE_RETURN (false);
+
+    /* Special-case to make it in-place and not consider this
+     * as a "ligated" substitution. */
+    if (unlikely (count == 1))
+    {
+      c->replace_glyph (ligGlyph);
+      return TRACE_RETURN (true);
+    }
 
     bool is_mark_ligature = false;
     unsigned int total_component_count = 0;
 
     unsigned int match_length = 0;
     unsigned int match_positions[MAX_CONTEXT_LENGTH];
 
     if (likely (!match_input (c, count,
                               &component[1],
                               match_glyph,
@@ skipping 693 matching lines @@
 }
 
 void
 GSUB::substitute_finish (hb_font_t *font HB_UNUSED, hb_buffer_t *buffer HB_UNUSED)
 {
 }
 
 
 /* Out-of-class implementation for methods recursing */
 
-inline bool ExtensionSubst::is_reverse (void) const
+/*static*/ inline bool ExtensionSubst::is_reverse (void) const
 {
   unsigned int type = get_type ();
   if (unlikely (type == SubstLookupSubTable::Extension))
     return CastR<ExtensionSubst> (get_subtable<SubstLookupSubTable>()).is_reverse ();
   return SubstLookup::lookup_type_is_reverse (type);
 }
 
 template <typename context_t>
-inline typename context_t::return_t SubstLookup::dispatch_recurse_func (context_t *c, unsigned int lookup_index)
+/*static*/ inline typename context_t::return_t SubstLookup::dispatch_recurse_func (context_t *c, unsigned int lookup_index)
 {
   const GSUB &gsub = *(hb_ot_layout_from_face (c->face)->gsub);
   const SubstLookup &l = gsub.get_lookup (lookup_index);
   return l.dispatch (c);
 }
 
-inline bool SubstLookup::apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index)
+/*static*/ inline bool SubstLookup::apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index)
 {
   const GSUB &gsub = *(hb_ot_layout_from_face (c->face)->gsub);
   const SubstLookup &l = gsub.get_lookup (lookup_index);
   unsigned int saved_lookup_props = c->lookup_props;
   c->set_lookup (l);
   bool ret = l.apply_once (c);
   c->lookup_props = saved_lookup_props;
   return ret;
 }
 
 
 } /* namespace OT */
 
 
 #endif /* HB_OT_LAYOUT_GSUB_TABLE_HH */