HarfBuzz: Update to version 5.1.0, use new FLAG_SAFE_TO_INSERT_TATWEEL flag to improve justification.

1 files changed, 299 insertions, 0 deletions

diff --git a/thirdparty/harfbuzz/src/graph/pairpos-graph.hh b/thirdparty/harfbuzz/src/graph/pairpos-graph.hh
new file mode 100644
index 0000000000..3ca4fc701c
--- /dev/null
+++ b/thirdparty/harfbuzz/src/graph/pairpos-graph.hh
@@ -0,0 +1,299 @@
+/*
+ * Copyright © 2022  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
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Garret Rieger
+ */
+
+#ifndef GRAPH_PAIRPOS_GRAPH_HH
+#define GRAPH_PAIRPOS_GRAPH_HH
+
+#include "coverage-graph.hh"
+#include "../OT/Layout/GPOS/PairPos.hh"
+#include "../OT/Layout/GPOS/PosLookupSubTable.hh"
+
+namespace graph {
+
+struct PairPosFormat1 : public OT::Layout::GPOS_impl::PairPosFormat1_3<SmallTypes>
+{
+  bool sanitize (graph_t::vertex_t& vertex) const
+  {
+    int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
+    unsigned min_size = OT::Layout::GPOS_impl::PairPosFormat1_3<SmallTypes>::min_size;
+    if (vertex_len < min_size) return false;
+
+    return vertex_len >=
+        min_size + pairSet.get_size () - pairSet.len.get_size();
+  }
+
+  hb_vector_t<unsigned> split_subtables (gsubgpos_graph_context_t& c, unsigned this_index)
+  {
+    hb_set_t visited;
+
+    const unsigned coverage_id = c.graph.index_for_offset (this_index, &coverage);
+    const unsigned coverage_size = c.graph.vertices_[coverage_id].table_size ();
+    const unsigned base_size = OT::Layout::GPOS_impl::PairPosFormat1_3<SmallTypes>::min_size
+                               + coverage_size;
+
+    unsigned accumulated = base_size;
+    hb_vector_t<unsigned> split_points;
+    for (unsigned i = 0; i < pairSet.len; i++)
+    {
+      unsigned pair_set_index = pair_set_graph_index (c, this_index, i);
+      accumulated += c.graph.find_subgraph_size (pair_set_index, visited);
+      accumulated += SmallTypes::size; // for PairSet offset.
+
+      // TODO(garretrieger): don't count the size of the largest pairset against the limit, since
+      //                     it will be packed last in the order and does not contribute to
+      //                     the 64kb limit.
+
+      if (accumulated > (1 << 16))
+      {
+        split_points.push (i);
+        accumulated = base_size;
+        visited.clear (); // Pretend node sharing isn't allowed between splits.
+      }
+    }
+
+    return do_split (c, this_index, split_points);
+  }
+
+ private:
+
+  // Split this PairPos into two or more PairPos's. split_points defines
+  // the indices (first index to include in the new table) to split at.
+  // Returns the object id's of the newly created PairPos subtables.
+  hb_vector_t<unsigned> do_split (gsubgpos_graph_context_t& c,
+                                  unsigned this_index,
+                                  const hb_vector_t<unsigned> split_points)
+  {
+    hb_vector_t<unsigned> new_objects;
+    if (!split_points)
+      return new_objects;
+
+    for (unsigned i = 0; i < split_points.length; i++)
+    {
+      unsigned start = split_points[i];
+      unsigned end = (i < split_points.length - 1) ? split_points[i + 1] : pairSet.len;
+      unsigned id = clone_range (c, this_index, start, end);
+
+      if (id == (unsigned) -1)
+      {
+        new_objects.reset ();
+        new_objects.allocated = -1; // mark error
+        return new_objects;
+      }
+      new_objects.push (id);
+    }
+
+    if (!shrink (c, this_index, split_points[0]))
+    {
+      new_objects.reset ();
+      new_objects.allocated = -1; // mark error
+    }
+
+    return new_objects;
+  }
+
+  bool shrink (gsubgpos_graph_context_t& c,
+               unsigned this_index,
+               unsigned count)
+  {
+    DEBUG_MSG (SUBSET_REPACK, nullptr,
+               "  Shrinking PairPosFormat1 (%u) to [0, %u).",
+               this_index,
+               count);
+    unsigned old_count = pairSet.len;
+    if (count >= old_count)
+      return true;
+
+    pairSet.len = count;
+    c.graph.vertices_[this_index].obj.tail -= (old_count - count) * SmallTypes::size;
+
+    unsigned coverage_id = c.graph.index_for_offset (this_index, &coverage);
+    unsigned coverage_size = c.graph.vertices_[coverage_id].table_size ();
+    auto& coverage_v = c.graph.vertices_[coverage_id];
+    Coverage* coverage_table = (Coverage*) coverage_v.obj.head;
+    if (!coverage_table->sanitize (coverage_v))
+      return false;
+
+    auto new_coverage =
+        + hb_zip (coverage_table->iter (), hb_range ())
+        | hb_filter ([&] (hb_pair_t<unsigned, unsigned> p) {
+          return p.second < count;
+        })
+        | hb_map_retains_sorting (hb_first)
+        ;
+
+    return make_coverage (c, new_coverage, coverage_id, coverage_size);
+  }
+
+  // Create a new PairPos including PairSet's from start (inclusive) to end (exclusive).
+  // Returns object id of the new object.
+  unsigned clone_range (gsubgpos_graph_context_t& c,
+                        unsigned this_index,
+                        unsigned start, unsigned end) const
+  {
+    DEBUG_MSG (SUBSET_REPACK, nullptr,
+               "  Cloning PairPosFormat1 (%u) range [%u, %u).", this_index, start, end);
+
+    unsigned num_pair_sets = end - start;
+    unsigned prime_size = OT::Layout::GPOS_impl::PairPosFormat1_3<SmallTypes>::min_size
+                          + num_pair_sets * SmallTypes::size;
+
+    unsigned pair_pos_prime_id = c.create_node (prime_size);
+    if (pair_pos_prime_id == (unsigned) -1) return -1;
+
+    PairPosFormat1* pair_pos_prime = (PairPosFormat1*) c.graph.object (pair_pos_prime_id).head;
+    pair_pos_prime->format = this->format;
+    pair_pos_prime->valueFormat[0] = this->valueFormat[0];
+    pair_pos_prime->valueFormat[1] = this->valueFormat[1];
+    pair_pos_prime->pairSet.len = num_pair_sets;
+
+    for (unsigned i = start; i < end; i++)
+    {
+      c.graph.move_child<> (this_index,
+                            &pairSet[i],
+                            pair_pos_prime_id,
+                            &pair_pos_prime->pairSet[i - start]);
+    }
+
+    unsigned coverage_id = c.graph.index_for_offset (this_index, &coverage);
+    unsigned coverage_size = c.graph.vertices_[coverage_id].table_size ();
+    auto& coverage_v = c.graph.vertices_[coverage_id];
+    Coverage* coverage_table = (Coverage*) coverage_v.obj.head;
+    if (!coverage_table->sanitize (coverage_v))
+      return false;
+
+    auto new_coverage =
+        + hb_zip (coverage_table->iter (), hb_range ())
+        | hb_filter ([&] (hb_pair_t<unsigned, unsigned> p) {
+          return p.second >= start && p.second < end;
+        })
+        | hb_map_retains_sorting (hb_first)
+        ;
+
+    unsigned coverage_prime_id = c.graph.new_node (nullptr, nullptr);
+    auto& coverage_prime_vertex = c.graph.vertices_[coverage_prime_id];
+    if (!make_coverage (c, new_coverage, coverage_prime_id, coverage_size))
+      return -1;
+
+    auto* coverage_link = c.graph.vertices_[pair_pos_prime_id].obj.real_links.push ();
+    coverage_link->width = SmallTypes::size;
+    coverage_link->objidx = coverage_prime_id;
+    coverage_link->position = 2;
+    coverage_prime_vertex.parents.push (pair_pos_prime_id);
+
+    return pair_pos_prime_id;
+  }
+
+  template<typename It>
+  bool make_coverage (gsubgpos_graph_context_t& c,
+                      It glyphs,
+                      unsigned dest_obj,
+                      unsigned max_size) const
+  {
+    char* buffer = (char*) hb_calloc (1, max_size);
+    hb_serialize_context_t serializer (buffer, max_size);
+    Coverage_serialize (&serializer, glyphs);
+    serializer.end_serialize ();
+    if (serializer.in_error ())
+    {
+      hb_free (buffer);
+      return false;
+    }
+
+    hb_bytes_t coverage_copy = serializer.copy_bytes ();
+    c.add_buffer ((char *) coverage_copy.arrayZ); // Give ownership to the context, it will cleanup the buffer.
+
+    auto& obj = c.graph.vertices_[dest_obj].obj;
+    obj.head = (char *) coverage_copy.arrayZ;
+    obj.tail = obj.head + coverage_copy.length;
+
+    hb_free (buffer);
+    return true;
+  }
+
+  unsigned pair_set_graph_index (gsubgpos_graph_context_t& c, unsigned this_index, unsigned i) const
+  {
+    return c.graph.index_for_offset (this_index, &pairSet[i]);
+  }
+};
+
+struct PairPosFormat2 : public OT::Layout::GPOS_impl::PairPosFormat2_4<SmallTypes>
+{
+  bool sanitize (graph_t::vertex_t& vertex) const
+  {
+    // TODO(garretrieger): implement me!
+    return true;
+  }
+
+  hb_vector_t<unsigned> split_subtables (gsubgpos_graph_context_t& c, unsigned this_index)
+  {
+    // TODO(garretrieger): implement me!
+    return hb_vector_t<unsigned> ();
+  }
+};
+
+struct PairPos : public OT::Layout::GPOS_impl::PairPos
+{
+  hb_vector_t<unsigned> split_subtables (gsubgpos_graph_context_t& c, unsigned this_index)
+  {
+    switch (u.format) {
+    case 1:
+      return ((PairPosFormat1*)(&u.format1))->split_subtables (c, this_index);
+    case 2:
+      return ((PairPosFormat2*)(&u.format2))->split_subtables (c, this_index);
+#ifndef HB_NO_BORING_EXPANSION
+    case 3: HB_FALLTHROUGH;
+    case 4: HB_FALLTHROUGH;
+      // Don't split 24bit PairPos's.
+#endif
+    default:
+      return hb_vector_t<unsigned> ();
+    }
+  }
+
+  bool sanitize (graph_t::vertex_t& vertex) const
+  {
+    int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
+    if (vertex_len < u.format.get_size ()) return false;
+
+    switch (u.format) {
+    case 1:
+      return ((PairPosFormat1*)(&u.format1))->sanitize (vertex);
+    case 2:
+      return ((PairPosFormat2*)(&u.format2))->sanitize (vertex);
+#ifndef HB_NO_BORING_EXPANSION
+    case 3: HB_FALLTHROUGH;
+    case 4: HB_FALLTHROUGH;
+#endif
+    default:
+      // We don't handle format 3 and 4 here.
+      return false;
+    }
+  }
+};
+
+}
+
+#endif  // GRAPH_PAIRPOS_GRAPH_HH