--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/harfbuzz/src/hb-face.cc	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,842 @@
+/*
+ * Copyright © 2009  Red Hat, Inc.
+ * Copyright © 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.
+ *
+ * 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.
+ *
+ * Red Hat Author(s): Behdad Esfahbod
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#include "hb.hh"
+
+#include "hb-face.hh"
+#include "hb-blob.hh"
+#include "hb-open-file.hh"
+#include "hb-ot-face.hh"
+#include "hb-ot-cmap-table.hh"
+#include "hb-map.hh"
+
+
+/**
+ * SECTION:hb-face
+ * @title: hb-face
+ * @short_description: Font face objects
+ * @include: hb.h
+ *
+ * A font face is an object that represents a single face from within a
+ * font family.
+ *
+ * More precisely, a font face represents a single face in a binary font file.
+ * Font faces are typically built from a binary blob and a face index.
+ * Font faces are used to create fonts.
+ **/
+
+
+/**
+ * hb_face_count:
+ * @blob: a blob.
+ *
+ * Fetches the number of faces in a blob.
+ *
+ * Return value: Number of faces in @blob
+ *
+ * Since: 1.7.7
+ **/
+unsigned int
+hb_face_count (hb_blob_t *blob)
+{
+  if (unlikely (!blob))
+    return 0;
+
+  /* TODO We shouldn't be sanitizing blob.  Port to run sanitizer and return if not sane. */
+  /* Make API signature const after. */
+  hb_blob_t *sanitized = hb_sanitize_context_t ().sanitize_blob<OT::OpenTypeFontFile> (hb_blob_reference (blob));
+  const OT::OpenTypeFontFile& ot = *sanitized->as<OT::OpenTypeFontFile> ();
+  unsigned int ret = ot.get_face_count ();
+  hb_blob_destroy (sanitized);
+
+  return ret;
+}
+
+/*
+ * hb_face_t
+ */
+
+DEFINE_NULL_INSTANCE (hb_face_t) =
+{
+  HB_OBJECT_HEADER_STATIC,
+
+  nullptr, /* reference_table_func */
+  nullptr, /* user_data */
+  nullptr, /* destroy */
+
+  0,    /* index */
+  1000, /* upem */
+  0,    /* num_glyphs */
+
+  /* Zero for the rest is fine. */
+};
+
+
+/**
+ * hb_face_create_for_tables:
+ * @reference_table_func: (closure user_data) (destroy destroy) (scope notified): Table-referencing function
+ * @user_data: A pointer to the user data
+ * @destroy: (nullable): A callback to call when @data is not needed anymore
+ *
+ * Variant of hb_face_create(), built for those cases where it is more
+ * convenient to provide data for individual tables instead of the whole font
+ * data. With the caveat that hb_face_get_table_tags() does not currently work
+ * with faces created this way.
+ *
+ * Creates a new face object from the specified @user_data and @reference_table_func,
+ * with the @destroy callback.
+ *
+ * Return value: (transfer full): The new face object
+ *
+ * Since: 0.9.2
+ **/
+hb_face_t *
+hb_face_create_for_tables (hb_reference_table_func_t  reference_table_func,
+			   void                      *user_data,
+			   hb_destroy_func_t          destroy)
+{
+  hb_face_t *face;
+
+  if (!reference_table_func || !(face = hb_object_create<hb_face_t> ())) {
+    if (destroy)
+      destroy (user_data);
+    return hb_face_get_empty ();
+  }
+
+  face->reference_table_func = reference_table_func;
+  face->user_data = user_data;
+  face->destroy = destroy;
+
+  face->num_glyphs = -1;
+
+  face->data.init0 (face);
+  face->table.init0 (face);
+
+  return face;
+}
+
+
+typedef struct hb_face_for_data_closure_t {
+  hb_blob_t *blob;
+  uint16_t  index;
+} hb_face_for_data_closure_t;
+
+static hb_face_for_data_closure_t *
+_hb_face_for_data_closure_create (hb_blob_t *blob, unsigned int index)
+{
+  hb_face_for_data_closure_t *closure;
+
+  closure = (hb_face_for_data_closure_t *) hb_calloc (1, sizeof (hb_face_for_data_closure_t));
+  if (unlikely (!closure))
+    return nullptr;
+
+  closure->blob = blob;
+  closure->index = (uint16_t) (index & 0xFFFFu);
+
+  return closure;
+}
+
+static void
+_hb_face_for_data_closure_destroy (void *data)
+{
+  hb_face_for_data_closure_t *closure = (hb_face_for_data_closure_t *) data;
+
+  hb_blob_destroy (closure->blob);
+  hb_free (closure);
+}
+
+static hb_blob_t *
+_hb_face_for_data_reference_table (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data)
+{
+  hb_face_for_data_closure_t *data = (hb_face_for_data_closure_t *) user_data;
+
+  if (tag == HB_TAG_NONE)
+    return hb_blob_reference (data->blob);
+
+  const OT::OpenTypeFontFile &ot_file = *data->blob->as<OT::OpenTypeFontFile> ();
+  unsigned int base_offset;
+  const OT::OpenTypeFontFace &ot_face = ot_file.get_face (data->index, &base_offset);
+
+  const OT::OpenTypeTable &table = ot_face.get_table_by_tag (tag);
+
+  hb_blob_t *blob = hb_blob_create_sub_blob (data->blob, base_offset + table.offset, table.length);
+
+  return blob;
+}
+
+/**
+ * hb_face_create:
+ * @blob: #hb_blob_t to work upon
+ * @index: The index of the face within @blob
+ *
+ * Constructs a new face object from the specified blob and
+ * a face index into that blob.
+ *
+ * The face index is used for blobs of file formats such as TTC and
+ * and DFont that can contain more than one face.  Face indices within
+ * such collections are zero-based.
+ *
+ * <note>Note: If the blob font format is not a collection, @index
+ * is ignored.  Otherwise, only the lower 16-bits of @index are used.
+ * The unmodified @index can be accessed via hb_face_get_index().</note>
+ *
+ * <note>Note: The high 16-bits of @index, if non-zero, are used by
+ * hb_font_create() to load named-instances in variable fonts.  See
+ * hb_font_create() for details.</note>
+ *
+ * Return value: (transfer full): The new face object
+ *
+ * Since: 0.9.2
+ **/
+hb_face_t *
+hb_face_create (hb_blob_t    *blob,
+		unsigned int  index)
+{
+  hb_face_t *face;
+
+  if (unlikely (!blob))
+    blob = hb_blob_get_empty ();
+
+  blob = hb_sanitize_context_t ().sanitize_blob<OT::OpenTypeFontFile> (hb_blob_reference (blob));
+
+  hb_face_for_data_closure_t *closure = _hb_face_for_data_closure_create (blob, index);
+
+  if (unlikely (!closure))
+  {
+    hb_blob_destroy (blob);
+    return hb_face_get_empty ();
+  }
+
+  face = hb_face_create_for_tables (_hb_face_for_data_reference_table,
+				    closure,
+				    _hb_face_for_data_closure_destroy);
+
+  face->index = index;
+
+  return face;
+}
+
+/**
+ * hb_face_get_empty:
+ *
+ * Fetches the singleton empty face object.
+ *
+ * Return value: (transfer full): The empty face object
+ *
+ * Since: 0.9.2
+ **/
+hb_face_t *
+hb_face_get_empty ()
+{
+  return const_cast<hb_face_t *> (&Null (hb_face_t));
+}
+
+
+/**
+ * hb_face_reference: (skip)
+ * @face: A face object
+ *
+ * Increases the reference count on a face object.
+ *
+ * Return value: The @face object
+ *
+ * Since: 0.9.2
+ **/
+hb_face_t *
+hb_face_reference (hb_face_t *face)
+{
+  return hb_object_reference (face);
+}
+
+/**
+ * hb_face_destroy: (skip)
+ * @face: A face object
+ *
+ * Decreases the reference count on a face object. When the
+ * reference count reaches zero, the face is destroyed,
+ * freeing all memory.
+ *
+ * Since: 0.9.2
+ **/
+void
+hb_face_destroy (hb_face_t *face)
+{
+  if (!hb_object_destroy (face)) return;
+
+#ifndef HB_NO_SHAPER
+  for (hb_face_t::plan_node_t *node = face->shape_plans; node; )
+  {
+    hb_face_t::plan_node_t *next = node->next;
+    hb_shape_plan_destroy (node->shape_plan);
+    hb_free (node);
+    node = next;
+  }
+#endif
+
+  face->data.fini ();
+  face->table.fini ();
+
+  if (face->destroy)
+    face->destroy (face->user_data);
+
+  hb_free (face);
+}
+
+/**
+ * hb_face_set_user_data: (skip)
+ * @face: A face object
+ * @key: The user-data key to set
+ * @data: A pointer to the user data
+ * @destroy: (nullable): A callback to call when @data is not needed anymore
+ * @replace: Whether to replace an existing data with the same key
+ *
+ * Attaches a user-data key/data pair to the given face object.
+ *
+ * Return value: `true` if success, `false` otherwise
+ *
+ * Since: 0.9.2
+ **/
+hb_bool_t
+hb_face_set_user_data (hb_face_t          *face,
+		       hb_user_data_key_t *key,
+		       void *              data,
+		       hb_destroy_func_t   destroy,
+		       hb_bool_t           replace)
+{
+  return hb_object_set_user_data (face, key, data, destroy, replace);
+}
+
+/**
+ * hb_face_get_user_data: (skip)
+ * @face: A face object
+ * @key: The user-data key to query
+ *
+ * Fetches the user data associated with the specified key,
+ * attached to the specified face object.
+ *
+ * Return value: (transfer none): A pointer to the user data
+ *
+ * Since: 0.9.2
+ **/
+void *
+hb_face_get_user_data (const hb_face_t    *face,
+		       hb_user_data_key_t *key)
+{
+  return hb_object_get_user_data (face, key);
+}
+
+/**
+ * hb_face_make_immutable:
+ * @face: A face object
+ *
+ * Makes the given face object immutable.
+ *
+ * Since: 0.9.2
+ **/
+void
+hb_face_make_immutable (hb_face_t *face)
+{
+  if (hb_object_is_immutable (face))
+    return;
+
+  hb_object_make_immutable (face);
+}
+
+/**
+ * hb_face_is_immutable:
+ * @face: A face object
+ *
+ * Tests whether the given face object is immutable.
+ *
+ * Return value: `true` is @face is immutable, `false` otherwise
+ *
+ * Since: 0.9.2
+ **/
+hb_bool_t
+hb_face_is_immutable (const hb_face_t *face)
+{
+  return hb_object_is_immutable (face);
+}
+
+
+/**
+ * hb_face_reference_table:
+ * @face: A face object
+ * @tag: The #hb_tag_t of the table to query
+ *
+ * Fetches a reference to the specified table within
+ * the specified face.
+ *
+ * Return value: (transfer full): A pointer to the @tag table within @face
+ *
+ * Since: 0.9.2
+ **/
+hb_blob_t *
+hb_face_reference_table (const hb_face_t *face,
+			 hb_tag_t tag)
+{
+  if (unlikely (tag == HB_TAG_NONE))
+    return hb_blob_get_empty ();
+
+  return face->reference_table (tag);
+}
+
+/**
+ * hb_face_reference_blob:
+ * @face: A face object
+ *
+ * Fetches a pointer to the binary blob that contains the
+ * specified face. Returns an empty blob if referencing face data is not
+ * possible.
+ *
+ * Return value: (transfer full): A pointer to the blob for @face
+ *
+ * Since: 0.9.2
+ **/
+hb_blob_t *
+hb_face_reference_blob (hb_face_t *face)
+{
+  return face->reference_table (HB_TAG_NONE);
+}
+
+/**
+ * hb_face_set_index:
+ * @face: A face object
+ * @index: The index to assign
+ *
+ * Assigns the specified face-index to @face. Fails if the
+ * face is immutable.
+ *
+ * <note>Note: changing the index has no effect on the face itself
+ * This only changes the value returned by hb_face_get_index().</note>
+ *
+ * Since: 0.9.2
+ **/
+void
+hb_face_set_index (hb_face_t    *face,
+		   unsigned int  index)
+{
+  if (hb_object_is_immutable (face))
+    return;
+
+  face->index = index;
+}
+
+/**
+ * hb_face_get_index:
+ * @face: A face object
+ *
+ * Fetches the face-index corresponding to the given face.
+ *
+ * <note>Note: face indices within a collection are zero-based.</note>
+ *
+ * Return value: The index of @face.
+ *
+ * Since: 0.9.2
+ **/
+unsigned int
+hb_face_get_index (const hb_face_t *face)
+{
+  return face->index;
+}
+
+/**
+ * hb_face_set_upem:
+ * @face: A face object
+ * @upem: The units-per-em value to assign
+ *
+ * Sets the units-per-em (upem) for a face object to the specified value.
+ *
+ * Since: 0.9.2
+ **/
+void
+hb_face_set_upem (hb_face_t    *face,
+		  unsigned int  upem)
+{
+  if (hb_object_is_immutable (face))
+    return;
+
+  face->upem = upem;
+}
+
+/**
+ * hb_face_get_upem:
+ * @face: A face object
+ *
+ * Fetches the units-per-em (upem) value of the specified face object.
+ *
+ * Return value: The upem value of @face
+ *
+ * Since: 0.9.2
+ **/
+unsigned int
+hb_face_get_upem (const hb_face_t *face)
+{
+  return face->get_upem ();
+}
+
+/**
+ * hb_face_set_glyph_count:
+ * @face: A face object
+ * @glyph_count: The glyph-count value to assign
+ *
+ * Sets the glyph count for a face object to the specified value.
+ *
+ * Since: 0.9.7
+ **/
+void
+hb_face_set_glyph_count (hb_face_t    *face,
+			 unsigned int  glyph_count)
+{
+  if (hb_object_is_immutable (face))
+    return;
+
+  face->num_glyphs = glyph_count;
+}
+
+/**
+ * hb_face_get_glyph_count:
+ * @face: A face object
+ *
+ * Fetches the glyph-count value of the specified face object.
+ *
+ * Return value: The glyph-count value of @face
+ *
+ * Since: 0.9.7
+ **/
+unsigned int
+hb_face_get_glyph_count (const hb_face_t *face)
+{
+  return face->get_num_glyphs ();
+}
+
+/**
+ * hb_face_get_table_tags:
+ * @face: A face object
+ * @start_offset: The index of first table tag to retrieve
+ * @table_count: (inout): Input = the maximum number of table tags to return;
+ *                Output = the actual number of table tags returned (may be zero)
+ * @table_tags: (out) (array length=table_count): The array of table tags found
+ *
+ * Fetches a list of all table tags for a face, if possible. The list returned will
+ * begin at the offset provided
+ *
+ * Return value: Total number of tables, or zero if it is not possible to list
+ *
+ * Since: 1.6.0
+ **/
+unsigned int
+hb_face_get_table_tags (const hb_face_t *face,
+			unsigned int  start_offset,
+			unsigned int *table_count, /* IN/OUT */
+			hb_tag_t     *table_tags /* OUT */)
+{
+  if (face->destroy != (hb_destroy_func_t) _hb_face_for_data_closure_destroy)
+  {
+    if (table_count)
+      *table_count = 0;
+    return 0;
+  }
+
+  hb_face_for_data_closure_t *data = (hb_face_for_data_closure_t *) face->user_data;
+
+  const OT::OpenTypeFontFile &ot_file = *data->blob->as<OT::OpenTypeFontFile> ();
+  const OT::OpenTypeFontFace &ot_face = ot_file.get_face (data->index);
+
+  return ot_face.get_table_tags (start_offset, table_count, table_tags);
+}
+
+
+/*
+ * Character set.
+ */
+
+
+#ifndef HB_NO_FACE_COLLECT_UNICODES
+/**
+ * hb_face_collect_unicodes:
+ * @face: A face object
+ * @out: The set to add Unicode characters to
+ *
+ * Collects all of the Unicode characters covered by @face and adds
+ * them to the #hb_set_t set @out.
+ *
+ * Since: 1.9.0
+ */
+void
+hb_face_collect_unicodes (hb_face_t *face,
+			  hb_set_t  *out)
+{
+  face->table.cmap->collect_unicodes (out, face->get_num_glyphs ());
+}
+/**
+ * hb_face_collect_variation_selectors:
+ * @face: A face object
+ * @out: The set to add Variation Selector characters to
+ *
+ * Collects all Unicode "Variation Selector" characters covered by @face and adds
+ * them to the #hb_set_t set @out.
+ *
+ * Since: 1.9.0
+ */
+void
+hb_face_collect_variation_selectors (hb_face_t *face,
+				     hb_set_t  *out)
+{
+  face->table.cmap->collect_variation_selectors (out);
+}
+/**
+ * hb_face_collect_variation_unicodes:
+ * @face: A face object
+ * @variation_selector: The Variation Selector to query
+ * @out: The set to add Unicode characters to
+ *
+ * Collects all Unicode characters for @variation_selector covered by @face and adds
+ * them to the #hb_set_t set @out.
+ *
+ * Since: 1.9.0
+ */
+void
+hb_face_collect_variation_unicodes (hb_face_t *face,
+				    hb_codepoint_t variation_selector,
+				    hb_set_t  *out)
+{
+  face->table.cmap->collect_variation_unicodes (variation_selector, out);
+}
+#endif
+
+
+/*
+ * face-builder: A face that has add_table().
+ */
+
+struct face_table_info_t
+{
+  hb_blob_t* data;
+  signed order;
+};
+
+struct hb_face_builder_data_t
+{
+  hb_hashmap_t<hb_tag_t, face_table_info_t> tables;
+};
+
+static int compare_entries (const void* pa, const void* pb)
+{
+  const auto& a = * (const hb_pair_t<hb_tag_t, face_table_info_t> *) pa;
+  const auto& b = * (const hb_pair_t<hb_tag_t, face_table_info_t> *) pb;
+
+  /* Order by blob size first (smallest to largest) and then table tag */
+
+  if (a.second.order != b.second.order)
+    return a.second.order < b.second.order ? -1 : +1;
+
+  if (a.second.data->length != b.second.data->length)
+    return a.second.data->length < b.second.data->length ? -1 : +1;
+
+  return a.first < b.first ? -1 : a.first == b.first ? 0 : +1;
+}
+
+static hb_face_builder_data_t *
+_hb_face_builder_data_create ()
+{
+  hb_face_builder_data_t *data = (hb_face_builder_data_t *) hb_calloc (1, sizeof (hb_face_builder_data_t));
+  if (unlikely (!data))
+    return nullptr;
+
+  data->tables.init ();
+
+  return data;
+}
+
+static void
+_hb_face_builder_data_destroy (void *user_data)
+{
+  hb_face_builder_data_t *data = (hb_face_builder_data_t *) user_data;
+
+  for (auto info : data->tables.values())
+    hb_blob_destroy (info.data);
+
+  data->tables.fini ();
+
+  hb_free (data);
+}
+
+static hb_blob_t *
+_hb_face_builder_data_reference_blob (hb_face_builder_data_t *data)
+{
+
+  unsigned int table_count = data->tables.get_population ();
+  unsigned int face_length = table_count * 16 + 12;
+
+  for (auto info : data->tables.values())
+    face_length += hb_ceil_to_4 (hb_blob_get_length (info.data));
+
+  char *buf = (char *) hb_malloc (face_length);
+  if (unlikely (!buf))
+    return nullptr;
+
+  hb_serialize_context_t c (buf, face_length);
+  c.propagate_error (data->tables);
+  OT::OpenTypeFontFile *f = c.start_serialize<OT::OpenTypeFontFile> ();
+
+  bool is_cff = (data->tables.has (HB_TAG ('C','F','F',' '))
+                 || data->tables.has (HB_TAG ('C','F','F','2')));
+  hb_tag_t sfnt_tag = is_cff ? OT::OpenTypeFontFile::CFFTag : OT::OpenTypeFontFile::TrueTypeTag;
+
+  // Sort the tags so that produced face is deterministic.
+  hb_vector_t<hb_pair_t <hb_tag_t, face_table_info_t>> sorted_entries;
+  data->tables.iter () | hb_sink (sorted_entries);
+  if (unlikely (sorted_entries.in_error ()))
+  {
+    hb_free (buf);
+    return nullptr;
+  }
+
+  sorted_entries.qsort (compare_entries);
+
+  bool ret = f->serialize_single (&c,
+                                  sfnt_tag,
+                                  + sorted_entries.iter()
+                                  | hb_map ([&] (hb_pair_t<hb_tag_t, face_table_info_t> _) {
+                                    return hb_pair_t<hb_tag_t, hb_blob_t*> (_.first, _.second.data);
+                                  }));
+
+  c.end_serialize ();
+
+  if (unlikely (!ret))
+  {
+    hb_free (buf);
+    return nullptr;
+  }
+
+  return hb_blob_create (buf, face_length, HB_MEMORY_MODE_WRITABLE, buf, hb_free);
+}
+
+static hb_blob_t *
+_hb_face_builder_reference_table (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data)
+{
+  hb_face_builder_data_t *data = (hb_face_builder_data_t *) user_data;
+
+  if (!tag)
+    return _hb_face_builder_data_reference_blob (data);
+
+  return hb_blob_reference (data->tables[tag].data);
+}
+
+
+/**
+ * hb_face_builder_create:
+ *
+ * Creates a #hb_face_t that can be used with hb_face_builder_add_table().
+ * After tables are added to the face, it can be compiled to a binary
+ * font file by calling hb_face_reference_blob().
+ *
+ * Return value: (transfer full): New face.
+ *
+ * Since: 1.9.0
+ **/
+hb_face_t *
+hb_face_builder_create ()
+{
+  hb_face_builder_data_t *data = _hb_face_builder_data_create ();
+  if (unlikely (!data)) return hb_face_get_empty ();
+
+  return hb_face_create_for_tables (_hb_face_builder_reference_table,
+				    data,
+				    _hb_face_builder_data_destroy);
+}
+
+/**
+ * hb_face_builder_add_table:
+ * @face: A face object created with hb_face_builder_create()
+ * @tag: The #hb_tag_t of the table to add
+ * @blob: The blob containing the table data to add
+ *
+ * Add table for @tag with data provided by @blob to the face.  @face must
+ * be created using hb_face_builder_create().
+ *
+ * Since: 1.9.0
+ **/
+hb_bool_t
+hb_face_builder_add_table (hb_face_t *face, hb_tag_t tag, hb_blob_t *blob)
+{
+  if (unlikely (face->destroy != (hb_destroy_func_t) _hb_face_builder_data_destroy))
+    return false;
+
+  if (tag == HB_MAP_VALUE_INVALID)
+    return false;
+
+  hb_face_builder_data_t *data = (hb_face_builder_data_t *) face->user_data;
+
+  hb_blob_t* previous = data->tables.get (tag).data;
+  if (!data->tables.set (tag, face_table_info_t {hb_blob_reference (blob), -1}))
+  {
+    hb_blob_destroy (blob);
+    return false;
+  }
+
+  hb_blob_destroy (previous);
+  return true;
+}
+
+/**
+ * hb_face_builder_sort_tables:
+ * @face: A face object created with hb_face_builder_create()
+ * @tags: (array zero-terminated=1): ordered list of table tags terminated by
+ *   %HB_TAG_NONE
+ *
+ * Set the ordering of tables for serialization. Any tables not
+ * specified in the tags list will be ordered after the tables in
+ * tags, ordered by the default sort ordering.
+ *
+ * Since: 5.3.0
+ **/
+void
+hb_face_builder_sort_tables (hb_face_t *face,
+                             const hb_tag_t  *tags)
+{
+  if (unlikely (face->destroy != (hb_destroy_func_t) _hb_face_builder_data_destroy))
+    return;
+
+  hb_face_builder_data_t *data = (hb_face_builder_data_t *) face->user_data;
+
+  // Sort all unspecified tables after any specified tables.
+  for (auto& info : data->tables.values_ref())
+    info.order = (unsigned) -1;
+
+  signed order = 0;
+  for (const hb_tag_t* tag = tags;
+       *tag;
+       tag++)
+  {
+    face_table_info_t* info;
+    if (!data->tables.has (*tag, &info)) continue;
+    info->order = order++;
+  }
+}