--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/harfbuzz/src/hb-subset-cff1.cc	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,926 @@
+/*
+ * Copyright © 2018 Adobe 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.
+ *
+ * Adobe Author(s): Michiharu Ariza
+ */
+
+#include "hb.hh"
+
+#ifndef HB_NO_SUBSET_CFF
+
+#include "hb-open-type.hh"
+#include "hb-ot-cff1-table.hh"
+#include "hb-set.h"
+#include "hb-bimap.hh"
+#include "hb-subset-cff1.hh"
+#include "hb-subset-plan.hh"
+#include "hb-subset-cff-common.hh"
+#include "hb-cff1-interp-cs.hh"
+
+using namespace CFF;
+
+struct remap_sid_t : hb_inc_bimap_t
+{
+  unsigned int add (unsigned int sid)
+  {
+    if ((sid != CFF_UNDEF_SID) && !is_std_std (sid))
+      return offset_sid (hb_inc_bimap_t::add (unoffset_sid (sid)));
+    else
+      return sid;
+  }
+
+  unsigned int operator[] (unsigned int sid) const
+  {
+    if (is_std_std (sid) || (sid == CFF_UNDEF_SID))
+      return sid;
+    else
+      return offset_sid (get (unoffset_sid (sid)));
+  }
+
+  static const unsigned int num_std_strings = 391;
+
+  static bool is_std_std (unsigned int sid) { return sid < num_std_strings; }
+  static unsigned int offset_sid (unsigned int sid) { return sid + num_std_strings; }
+  static unsigned int unoffset_sid (unsigned int sid) { return sid - num_std_strings; }
+};
+
+struct cff1_sub_table_info_t : cff_sub_table_info_t
+{
+  cff1_sub_table_info_t ()
+    : cff_sub_table_info_t (),
+      encoding_link (0),
+      charset_link (0)
+   {
+    privateDictInfo.init ();
+  }
+
+  objidx_t	encoding_link;
+  objidx_t	charset_link;
+  table_info_t	privateDictInfo;
+};
+
+/* a copy of a parsed out cff1_top_dict_values_t augmented with additional operators */
+struct cff1_top_dict_values_mod_t : cff1_top_dict_values_t
+{
+  void init (const cff1_top_dict_values_t *base_= &Null (cff1_top_dict_values_t))
+  {
+    SUPER::init ();
+    base = base_;
+  }
+
+  void fini () { SUPER::fini (); }
+
+  unsigned get_count () const { return base->get_count () + SUPER::get_count (); }
+  const cff1_top_dict_val_t &get_value (unsigned int i) const
+  {
+    if (i < base->get_count ())
+      return (*base)[i];
+    else
+      return SUPER::values[i - base->get_count ()];
+  }
+  const cff1_top_dict_val_t &operator [] (unsigned int i) const { return get_value (i); }
+
+  void reassignSIDs (const remap_sid_t& sidmap)
+  {
+    for (unsigned int i = 0; i < name_dict_values_t::ValCount; i++)
+      nameSIDs[i] = sidmap[base->nameSIDs[i]];
+  }
+
+  protected:
+  typedef cff1_top_dict_values_t SUPER;
+  const cff1_top_dict_values_t *base;
+};
+
+struct top_dict_modifiers_t
+{
+  top_dict_modifiers_t (const cff1_sub_table_info_t &info_,
+			const unsigned int (&nameSIDs_)[name_dict_values_t::ValCount])
+    : info (info_),
+      nameSIDs (nameSIDs_)
+  {}
+
+  const cff1_sub_table_info_t &info;
+  const unsigned int	(&nameSIDs)[name_dict_values_t::ValCount];
+};
+
+struct cff1_top_dict_op_serializer_t : cff_top_dict_op_serializer_t<cff1_top_dict_val_t>
+{
+  bool serialize (hb_serialize_context_t *c,
+		  const cff1_top_dict_val_t &opstr,
+		  const top_dict_modifiers_t &mod) const
+  {
+    TRACE_SERIALIZE (this);
+
+    op_code_t op = opstr.op;
+    switch (op)
+    {
+      case OpCode_charset:
+	if (mod.info.charset_link)
+	  return_trace (FontDict::serialize_link4_op(c, op, mod.info.charset_link, whence_t::Absolute));
+	else
+	  goto fall_back;
+
+      case OpCode_Encoding:
+	if (mod.info.encoding_link)
+	  return_trace (FontDict::serialize_link4_op(c, op, mod.info.encoding_link, whence_t::Absolute));
+	else
+	  goto fall_back;
+
+      case OpCode_Private:
+	return_trace (UnsizedByteStr::serialize_int2 (c, mod.info.privateDictInfo.size) &&
+		      Dict::serialize_link4_op (c, op, mod.info.privateDictInfo.link, whence_t::Absolute));
+
+      case OpCode_version:
+      case OpCode_Notice:
+      case OpCode_Copyright:
+      case OpCode_FullName:
+      case OpCode_FamilyName:
+      case OpCode_Weight:
+      case OpCode_PostScript:
+      case OpCode_BaseFontName:
+      case OpCode_FontName:
+	return_trace (FontDict::serialize_int2_op (c, op, mod.nameSIDs[name_dict_values_t::name_op_to_index (op)]));
+
+      case OpCode_ROS:
+	{
+	  /* for registry & ordering, reassigned SIDs are serialized
+	   * for supplement, the original byte string is copied along with the op code */
+	  op_str_t supp_op;
+	  supp_op.op = op;
+	  if ( unlikely (!(opstr.length >= opstr.last_arg_offset + 3)))
+	    return_trace (false);
+	  supp_op.ptr = opstr.ptr + opstr.last_arg_offset;
+	  supp_op.length = opstr.length - opstr.last_arg_offset;
+	  return_trace (UnsizedByteStr::serialize_int2 (c, mod.nameSIDs[name_dict_values_t::registry]) &&
+			UnsizedByteStr::serialize_int2 (c, mod.nameSIDs[name_dict_values_t::ordering]) &&
+			copy_opstr (c, supp_op));
+	}
+      fall_back:
+      default:
+	return_trace (cff_top_dict_op_serializer_t<cff1_top_dict_val_t>::serialize (c, opstr, mod.info));
+    }
+    return_trace (true);
+  }
+
+};
+
+struct cff1_font_dict_op_serializer_t : cff_font_dict_op_serializer_t
+{
+  bool serialize (hb_serialize_context_t *c,
+		  const op_str_t &opstr,
+		  const cff1_font_dict_values_mod_t &mod) const
+  {
+    TRACE_SERIALIZE (this);
+
+    if (opstr.op == OpCode_FontName)
+      return_trace (FontDict::serialize_int2_op (c, opstr.op, mod.fontName));
+    else
+      return_trace (SUPER::serialize (c, opstr, mod.privateDictInfo));
+  }
+
+  private:
+  typedef cff_font_dict_op_serializer_t SUPER;
+};
+
+struct cff1_cs_opset_flatten_t : cff1_cs_opset_t<cff1_cs_opset_flatten_t, flatten_param_t>
+{
+  static void flush_args_and_op (op_code_t op, cff1_cs_interp_env_t &env, flatten_param_t& param)
+  {
+    if (env.arg_start > 0)
+      flush_width (env, param);
+
+    switch (op)
+    {
+      case OpCode_hstem:
+      case OpCode_hstemhm:
+      case OpCode_vstem:
+      case OpCode_vstemhm:
+      case OpCode_hintmask:
+      case OpCode_cntrmask:
+      case OpCode_dotsection:
+	if (param.drop_hints)
+	{
+	  env.clear_args ();
+	  return;
+	}
+	HB_FALLTHROUGH;
+
+      default:
+	SUPER::flush_args_and_op (op, env, param);
+	break;
+    }
+  }
+  static void flush_args (cff1_cs_interp_env_t &env, flatten_param_t& param)
+  {
+    str_encoder_t  encoder (param.flatStr);
+    for (unsigned int i = env.arg_start; i < env.argStack.get_count (); i++)
+      encoder.encode_num (env.eval_arg (i));
+    SUPER::flush_args (env, param);
+  }
+
+  static void flush_op (op_code_t op, cff1_cs_interp_env_t &env, flatten_param_t& param)
+  {
+    str_encoder_t  encoder (param.flatStr);
+    encoder.encode_op (op);
+  }
+
+  static void flush_width (cff1_cs_interp_env_t &env, flatten_param_t& param)
+  {
+    assert (env.has_width);
+    str_encoder_t  encoder (param.flatStr);
+    encoder.encode_num (env.width);
+  }
+
+  static void flush_hintmask (op_code_t op, cff1_cs_interp_env_t &env, flatten_param_t& param)
+  {
+    SUPER::flush_hintmask (op, env, param);
+    if (!param.drop_hints)
+    {
+      str_encoder_t  encoder (param.flatStr);
+      for (unsigned int i = 0; i < env.hintmask_size; i++)
+	encoder.encode_byte (env.str_ref[i]);
+    }
+  }
+
+  private:
+  typedef cff1_cs_opset_t<cff1_cs_opset_flatten_t, flatten_param_t> SUPER;
+};
+
+struct range_list_t : hb_vector_t<code_pair_t>
+{
+  /* replace the first glyph ID in the "glyph" field each range with a nLeft value */
+  bool complete (unsigned int last_glyph)
+  {
+    bool two_byte = false;
+    unsigned count = this->length;
+    for (unsigned int i = count; i; i--)
+    {
+      code_pair_t &pair = arrayZ[i - 1];
+      unsigned int nLeft = last_glyph - pair.glyph - 1;
+      two_byte |= nLeft >= 0x100;
+      last_glyph = pair.glyph;
+      pair.glyph = nLeft;
+    }
+    return two_byte;
+  }
+};
+
+struct cff1_cs_opset_subr_subset_t : cff1_cs_opset_t<cff1_cs_opset_subr_subset_t, subr_subset_param_t>
+{
+  static void process_op (op_code_t op, cff1_cs_interp_env_t &env, subr_subset_param_t& param)
+  {
+    switch (op) {
+
+      case OpCode_return:
+	param.current_parsed_str->add_op (op, env.str_ref);
+	param.current_parsed_str->set_parsed ();
+	env.return_from_subr ();
+	param.set_current_str (env, false);
+	break;
+
+      case OpCode_endchar:
+	param.current_parsed_str->add_op (op, env.str_ref);
+	param.current_parsed_str->set_parsed ();
+	SUPER::process_op (op, env, param);
+	break;
+
+      case OpCode_callsubr:
+	process_call_subr (op, CSType_LocalSubr, env, param, env.localSubrs, param.local_closure);
+	break;
+
+      case OpCode_callgsubr:
+	process_call_subr (op, CSType_GlobalSubr, env, param, env.globalSubrs, param.global_closure);
+	break;
+
+      default:
+	SUPER::process_op (op, env, param);
+	param.current_parsed_str->add_op (op, env.str_ref);
+	break;
+    }
+  }
+
+  protected:
+  static void process_call_subr (op_code_t op, cs_type_t type,
+				 cff1_cs_interp_env_t &env, subr_subset_param_t& param,
+				 cff1_biased_subrs_t& subrs, hb_set_t *closure)
+  {
+    byte_str_ref_t    str_ref = env.str_ref;
+    env.call_subr (subrs, type);
+    param.current_parsed_str->add_call_op (op, str_ref, env.context.subr_num);
+    closure->add (env.context.subr_num);
+    param.set_current_str (env, true);
+  }
+
+  private:
+  typedef cff1_cs_opset_t<cff1_cs_opset_subr_subset_t, subr_subset_param_t> SUPER;
+};
+
+struct cff1_subr_subsetter_t : subr_subsetter_t<cff1_subr_subsetter_t, CFF1Subrs, const OT::cff1::accelerator_subset_t, cff1_cs_interp_env_t, cff1_cs_opset_subr_subset_t, OpCode_endchar>
+{
+  cff1_subr_subsetter_t (const OT::cff1::accelerator_subset_t &acc_, const hb_subset_plan_t *plan_)
+    : subr_subsetter_t (acc_, plan_) {}
+
+  static void complete_parsed_str (cff1_cs_interp_env_t &env, subr_subset_param_t& param, parsed_cs_str_t &charstring)
+  {
+    /* insert width at the beginning of the charstring as necessary */
+    if (env.has_width)
+      charstring.set_prefix (env.width);
+
+    /* subroutines/charstring left on the call stack are legally left unmarked
+     * unmarked when a subroutine terminates with endchar. mark them.
+     */
+    param.current_parsed_str->set_parsed ();
+    for (unsigned int i = 0; i < env.callStack.get_count (); i++)
+    {
+      parsed_cs_str_t *parsed_str = param.get_parsed_str_for_context (env.callStack[i]);
+      if (likely (parsed_str))
+	parsed_str->set_parsed ();
+      else
+	env.set_error ();
+    }
+  }
+};
+
+struct cff_subset_plan {
+  cff_subset_plan ()
+  {
+    for (unsigned int i = 0; i < name_dict_values_t::ValCount; i++)
+      topDictModSIDs[i] = CFF_UNDEF_SID;
+  }
+
+  void plan_subset_encoding (const OT::cff1::accelerator_subset_t &acc, hb_subset_plan_t *plan)
+  {
+    const Encoding *encoding = acc.encoding;
+    unsigned int  size0, size1;
+    hb_codepoint_t  code, last_code = CFF_UNDEF_CODE;
+    hb_vector_t<hb_codepoint_t> supp_codes;
+
+    if (unlikely (!subset_enc_code_ranges.resize (0)))
+    {
+      plan->check_success (false);
+      return;
+    }
+
+    supp_codes.init ();
+
+    subset_enc_num_codes = plan->num_output_glyphs () - 1;
+    unsigned int glyph;
+    for (glyph = 1; glyph < plan->num_output_glyphs (); glyph++)
+    {
+      hb_codepoint_t  old_glyph;
+      if (!plan->old_gid_for_new_gid (glyph, &old_glyph))
+      {
+	/* Retain the code for the old missing glyph ID */
+	old_glyph = glyph;
+      }
+      code = acc.glyph_to_code (old_glyph);
+      if (code == CFF_UNDEF_CODE)
+      {
+	subset_enc_num_codes = glyph - 1;
+	break;
+      }
+
+      if ((last_code == CFF_UNDEF_CODE) || (code != last_code + 1))
+      {
+	code_pair_t pair = { code, glyph };
+	subset_enc_code_ranges.push (pair);
+      }
+      last_code = code;
+
+      if (encoding != &Null (Encoding))
+      {
+	hb_codepoint_t  sid = acc.glyph_to_sid (old_glyph);
+	encoding->get_supplement_codes (sid, supp_codes);
+	for (unsigned int i = 0; i < supp_codes.length; i++)
+	{
+	  code_pair_t pair = { supp_codes[i], sid };
+	  subset_enc_supp_codes.push (pair);
+	}
+      }
+    }
+    supp_codes.fini ();
+
+    subset_enc_code_ranges.complete (glyph);
+
+    assert (subset_enc_num_codes <= 0xFF);
+    size0 = Encoding0::min_size + HBUINT8::static_size * subset_enc_num_codes;
+    size1 = Encoding1::min_size + Encoding1_Range::static_size * subset_enc_code_ranges.length;
+
+    if (size0 < size1)
+      subset_enc_format = 0;
+    else
+      subset_enc_format = 1;
+  }
+
+  void plan_subset_charset (const OT::cff1::accelerator_subset_t &acc, hb_subset_plan_t *plan)
+  {
+    unsigned int  size0, size_ranges;
+    hb_codepoint_t  sid, last_sid = CFF_UNDEF_CODE;
+
+    if (unlikely (!subset_charset_ranges.resize (0)))
+    {
+      plan->check_success (false);
+      return;
+    }
+
+    hb_map_t *glyph_to_sid_map = (plan->accelerator && plan->accelerator->cff_accelerator) ?
+				  plan->accelerator->cff_accelerator->glyph_to_sid_map :
+				  nullptr;
+    bool created_map = false;
+    if (!glyph_to_sid_map &&
+	((plan->accelerator && plan->accelerator->cff_accelerator) ||
+	 plan->num_output_glyphs () > plan->source->get_num_glyphs () / 8.))
+    {
+      created_map = true;
+      glyph_to_sid_map = acc.create_glyph_to_sid_map ();
+    }
+
+    unsigned int glyph;
+    for (glyph = 1; glyph < plan->num_output_glyphs (); glyph++)
+    {
+      hb_codepoint_t  old_glyph;
+      if (!plan->old_gid_for_new_gid (glyph, &old_glyph))
+      {
+	/* Retain the SID for the old missing glyph ID */
+	old_glyph = glyph;
+      }
+      sid = glyph_to_sid_map ? glyph_to_sid_map->get (old_glyph) : acc.glyph_to_sid (old_glyph);
+
+      if (!acc.is_CID ())
+	sid = sidmap.add (sid);
+
+      if ((last_sid == CFF_UNDEF_CODE) || (sid != last_sid + 1))
+      {
+	code_pair_t pair = { sid, glyph };
+	subset_charset_ranges.push (pair);
+      }
+      last_sid = sid;
+    }
+
+    if (created_map)
+    {
+      if (!(plan->accelerator && plan->accelerator->cff_accelerator) ||
+	  !plan->accelerator->cff_accelerator->glyph_to_sid_map.cmpexch (nullptr, glyph_to_sid_map))
+	hb_map_destroy (glyph_to_sid_map);
+    }
+
+    bool two_byte = subset_charset_ranges.complete (glyph);
+
+    size0 = Charset0::min_size + HBUINT16::static_size * (plan->num_output_glyphs () - 1);
+    if (!two_byte)
+      size_ranges = Charset1::min_size + Charset1_Range::static_size * subset_charset_ranges.length;
+    else
+      size_ranges = Charset2::min_size + Charset2_Range::static_size * subset_charset_ranges.length;
+
+    if (size0 < size_ranges)
+      subset_charset_format = 0;
+    else if (!two_byte)
+      subset_charset_format = 1;
+    else
+      subset_charset_format = 2;
+  }
+
+  bool collect_sids_in_dicts (const OT::cff1::accelerator_subset_t &acc)
+  {
+    sidmap.reset ();
+
+    for (unsigned int i = 0; i < name_dict_values_t::ValCount; i++)
+    {
+      unsigned int sid = acc.topDict.nameSIDs[i];
+      if (sid != CFF_UNDEF_SID)
+      {
+	(void)sidmap.add (sid);
+	topDictModSIDs[i] = sidmap[sid];
+      }
+    }
+
+    if (acc.fdArray != &Null (CFF1FDArray))
+      for (unsigned int i = 0; i < orig_fdcount; i++)
+	if (fdmap.has (i))
+	  (void)sidmap.add (acc.fontDicts[i].fontName);
+
+    return true;
+  }
+
+  bool create (const OT::cff1::accelerator_subset_t &acc,
+	       hb_subset_plan_t *plan)
+  {
+    /* make sure notdef is first */
+    hb_codepoint_t old_glyph;
+    if (!plan->old_gid_for_new_gid (0, &old_glyph) || (old_glyph != 0)) return false;
+
+    num_glyphs = plan->num_output_glyphs ();
+    orig_fdcount = acc.fdCount;
+    drop_hints = plan->flags & HB_SUBSET_FLAGS_NO_HINTING;
+    desubroutinize = plan->flags & HB_SUBSET_FLAGS_DESUBROUTINIZE;
+
+    /* check whether the subset renumbers any glyph IDs */
+    gid_renum = false;
+    for (hb_codepoint_t new_glyph = 0; new_glyph < plan->num_output_glyphs (); new_glyph++)
+    {
+      if (!plan->old_gid_for_new_gid(new_glyph, &old_glyph))
+	continue;
+      if (new_glyph != old_glyph) {
+	gid_renum = true;
+	break;
+      }
+    }
+
+    subset_charset = gid_renum || !acc.is_predef_charset ();
+    subset_encoding = !acc.is_CID() && !acc.is_predef_encoding ();
+
+    /* top dict INDEX */
+    {
+      /* Add encoding/charset to a (copy of) top dict as necessary */
+      topdict_mod.init (&acc.topDict);
+      bool need_to_add_enc = (subset_encoding && !acc.topDict.has_op (OpCode_Encoding));
+      bool need_to_add_set = (subset_charset && !acc.topDict.has_op (OpCode_charset));
+      if (need_to_add_enc || need_to_add_set)
+      {
+	if (need_to_add_enc)
+	  topdict_mod.add_op (OpCode_Encoding);
+	if (need_to_add_set)
+	  topdict_mod.add_op (OpCode_charset);
+      }
+    }
+
+    /* Determine re-mapping of font index as fdmap among other info */
+    if (acc.fdSelect != &Null (CFF1FDSelect))
+    {
+	if (unlikely (!hb_plan_subset_cff_fdselect (plan,
+				  orig_fdcount,
+				  *acc.fdSelect,
+				  subset_fdcount,
+				  info.fd_select.size,
+				  subset_fdselect_format,
+				  subset_fdselect_ranges,
+				  fdmap)))
+	return false;
+    }
+    else
+      fdmap.identity (1);
+
+    /* remove unused SIDs & reassign SIDs */
+    {
+      /* SIDs for name strings in dicts are added before glyph names so they fit in 16-bit int range */
+      if (unlikely (!collect_sids_in_dicts (acc)))
+	return false;
+      if (unlikely (sidmap.get_population () > 0x8000))	/* assumption: a dict won't reference that many strings */
+	return false;
+
+      if (subset_charset) plan_subset_charset (acc, plan);
+
+      topdict_mod.reassignSIDs (sidmap);
+    }
+
+    if (desubroutinize)
+    {
+      /* Flatten global & local subrs */
+      subr_flattener_t<const OT::cff1::accelerator_subset_t, cff1_cs_interp_env_t, cff1_cs_opset_flatten_t, OpCode_endchar>
+		    flattener(acc, plan);
+      if (!flattener.flatten (subset_charstrings))
+	return false;
+    }
+    else
+    {
+      cff1_subr_subsetter_t       subr_subsetter (acc, plan);
+
+      /* Subset subrs: collect used subroutines, leaving all unused ones behind */
+      if (!subr_subsetter.subset ())
+	return false;
+
+      /* encode charstrings, global subrs, local subrs with new subroutine numbers */
+      if (!subr_subsetter.encode_charstrings (subset_charstrings))
+	return false;
+
+      if (!subr_subsetter.encode_globalsubrs (subset_globalsubrs))
+	return false;
+
+      /* local subrs */
+      if (!subset_localsubrs.resize (orig_fdcount))
+	return false;
+      for (unsigned int fd = 0; fd < orig_fdcount; fd++)
+      {
+	subset_localsubrs[fd].init ();
+	if (fdmap.has (fd))
+	{
+	  if (!subr_subsetter.encode_localsubrs (fd, subset_localsubrs[fd]))
+	    return false;
+	}
+      }
+    }
+
+    /* Encoding */
+    if (subset_encoding)
+      plan_subset_encoding (acc, plan);
+
+    /* private dicts & local subrs */
+    if (!acc.is_CID ())
+      fontdicts_mod.push (cff1_font_dict_values_mod_t ());
+    else
+    {
+      + hb_iter (acc.fontDicts)
+      | hb_filter ([&] (const cff1_font_dict_values_t &_)
+	{ return fdmap.has (&_ - &acc.fontDicts[0]); } )
+      | hb_map ([&] (const cff1_font_dict_values_t &_)
+	{
+	  cff1_font_dict_values_mod_t mod;
+	  mod.init (&_, sidmap[_.fontName]);
+	  return mod;
+	})
+      | hb_sink (fontdicts_mod)
+      ;
+    }
+
+    return ((subset_charstrings.length == plan->num_output_glyphs ())
+	   && (fontdicts_mod.length == subset_fdcount));
+  }
+
+  cff1_top_dict_values_mod_t	topdict_mod;
+  cff1_sub_table_info_t		info;
+
+  unsigned int    num_glyphs;
+  unsigned int    orig_fdcount = 0;
+  unsigned int    subset_fdcount = 1;
+  unsigned int    subset_fdselect_format = 0;
+  hb_vector_t<code_pair_t>   subset_fdselect_ranges;
+
+  /* font dict index remap table from fullset FDArray to subset FDArray.
+   * set to CFF_UNDEF_CODE if excluded from subset */
+  hb_inc_bimap_t   fdmap;
+
+  str_buff_vec_t		subset_charstrings;
+  str_buff_vec_t		subset_globalsubrs;
+  hb_vector_t<str_buff_vec_t>	subset_localsubrs;
+  hb_vector_t<cff1_font_dict_values_mod_t>  fontdicts_mod;
+
+  bool		drop_hints = false;
+
+  bool		gid_renum;
+  bool		subset_encoding;
+  uint8_t	subset_enc_format;
+  unsigned int	subset_enc_num_codes;
+  range_list_t	subset_enc_code_ranges;
+  hb_vector_t<code_pair_t>  subset_enc_supp_codes;
+
+  uint8_t	subset_charset_format;
+  range_list_t	subset_charset_ranges;
+  bool		subset_charset;
+
+  remap_sid_t	sidmap;
+  unsigned int	topDictModSIDs[name_dict_values_t::ValCount];
+
+  bool		desubroutinize = false;
+};
+
+static bool _serialize_cff1 (hb_serialize_context_t *c,
+			     cff_subset_plan &plan,
+			     const OT::cff1::accelerator_subset_t  &acc,
+			     unsigned int num_glyphs)
+{
+  /* private dicts & local subrs */
+  for (int i = (int)acc.privateDicts.length; --i >= 0 ;)
+  {
+    if (plan.fdmap.has (i))
+    {
+      objidx_t	subrs_link = 0;
+      if (plan.subset_localsubrs[i].length > 0)
+      {
+	CFF1Subrs *dest = c->start_embed <CFF1Subrs> ();
+	if (unlikely (!dest)) return false;
+	c->push ();
+	if (likely (dest && dest->serialize (c, plan.subset_localsubrs[i])))
+	  subrs_link = c->pop_pack ();
+	else
+	{
+	  c->pop_discard ();
+	  return false;
+	}
+      }
+
+      PrivateDict *pd = c->start_embed<PrivateDict> ();
+      if (unlikely (!pd)) return false;
+      c->push ();
+      cff_private_dict_op_serializer_t privSzr (plan.desubroutinize, plan.drop_hints);
+      /* N.B. local subrs immediately follows its corresponding private dict. i.e., subr offset == private dict size */
+      if (likely (pd->serialize (c, acc.privateDicts[i], privSzr, subrs_link)))
+      {
+	unsigned fd = plan.fdmap[i];
+	plan.fontdicts_mod[fd].privateDictInfo.size = c->length ();
+	plan.fontdicts_mod[fd].privateDictInfo.link = c->pop_pack ();
+      }
+      else
+      {
+	c->pop_discard ();
+	return false;
+      }
+    }
+  }
+
+  if (!acc.is_CID ())
+    plan.info.privateDictInfo = plan.fontdicts_mod[0].privateDictInfo;
+
+  /* CharStrings */
+  {
+    c->push<CFF1CharStrings> ();
+
+    unsigned total_size = CFF1CharStrings::total_size (plan.subset_charstrings);
+    if (unlikely (!c->start_zerocopy (total_size)))
+       return false;
+
+    CFF1CharStrings  *cs = c->start_embed<CFF1CharStrings> ();
+    if (unlikely (!cs)) return false;
+
+    if (likely (cs->serialize (c, plan.subset_charstrings)))
+      plan.info.char_strings_link = c->pop_pack (false);
+    else
+    {
+      c->pop_discard ();
+      return false;
+    }
+  }
+
+  /* FDArray (FD Index) */
+  if (acc.fdArray != &Null (CFF1FDArray))
+  {
+    CFF1FDArray *fda = c->start_embed<CFF1FDArray> ();
+    if (unlikely (!fda)) return false;
+    c->push ();
+    cff1_font_dict_op_serializer_t  fontSzr;
+    auto it = + hb_zip (+ hb_iter (plan.fontdicts_mod), + hb_iter (plan.fontdicts_mod));
+    if (likely (fda->serialize (c, it, fontSzr)))
+      plan.info.fd_array_link = c->pop_pack (false);
+    else
+    {
+      c->pop_discard ();
+      return false;
+    }
+  }
+
+  /* FDSelect */
+  if (acc.fdSelect != &Null (CFF1FDSelect))
+  {
+    c->push ();
+    if (likely (hb_serialize_cff_fdselect (c, num_glyphs, *acc.fdSelect, acc.fdCount,
+					   plan.subset_fdselect_format, plan.info.fd_select.size,
+					   plan.subset_fdselect_ranges)))
+      plan.info.fd_select.link = c->pop_pack ();
+    else
+    {
+      c->pop_discard ();
+      return false;
+    }
+  }
+
+  /* Charset */
+  if (plan.subset_charset)
+  {
+    Charset *dest = c->start_embed<Charset> ();
+    if (unlikely (!dest)) return false;
+    c->push ();
+    if (likely (dest->serialize (c,
+				 plan.subset_charset_format,
+				 plan.num_glyphs,
+				 plan.subset_charset_ranges)))
+      plan.info.charset_link = c->pop_pack ();
+    else
+    {
+      c->pop_discard ();
+      return false;
+    }
+  }
+
+  /* Encoding */
+  if (plan.subset_encoding)
+  {
+    Encoding *dest = c->start_embed<Encoding> ();
+    if (unlikely (!dest)) return false;
+    c->push ();
+    if (likely (dest->serialize (c,
+				 plan.subset_enc_format,
+				 plan.subset_enc_num_codes,
+				 plan.subset_enc_code_ranges,
+				 plan.subset_enc_supp_codes)))
+      plan.info.encoding_link = c->pop_pack ();
+    else
+    {
+      c->pop_discard ();
+      return false;
+    }
+  }
+
+  /* global subrs */
+  {
+    c->push ();
+    CFF1Subrs *dest = c->start_embed <CFF1Subrs> ();
+    if (unlikely (!dest)) return false;
+    if (likely (dest->serialize (c, plan.subset_globalsubrs)))
+      c->pop_pack (false);
+    else
+    {
+      c->pop_discard ();
+      return false;
+    }
+  }
+
+  /* String INDEX */
+  {
+    CFF1StringIndex *dest = c->start_embed<CFF1StringIndex> ();
+    if (unlikely (!dest)) return false;
+    c->push ();
+    if (likely (dest->serialize (c, *acc.stringIndex, plan.sidmap)))
+      c->pop_pack ();
+    else
+    {
+      c->pop_discard ();
+      return false;
+    }
+  }
+
+  OT::cff1 *cff = c->allocate_min<OT::cff1> ();
+  if (unlikely (!cff))
+    return false;
+
+  /* header */
+  cff->version.major = 0x01;
+  cff->version.minor = 0x00;
+  cff->nameIndex = cff->min_size;
+  cff->offSize = 4; /* unused? */
+
+  /* name INDEX */
+  if (unlikely (!(*acc.nameIndex).copy (c))) return false;
+
+  /* top dict INDEX */
+  {
+    /* serialize singleton TopDict */
+    TopDict *top = c->start_embed<TopDict> ();
+    if (!top) return false;
+    c->push ();
+    cff1_top_dict_op_serializer_t topSzr;
+    unsigned top_size = 0;
+    top_dict_modifiers_t  modifier (plan.info, plan.topDictModSIDs);
+    if (likely (top->serialize (c, plan.topdict_mod, topSzr, modifier)))
+    {
+      top_size = c->length ();
+      c->pop_pack (false);
+    }
+    else
+    {
+      c->pop_discard ();
+      return false;
+    }
+    /* serialize INDEX header for above */
+    CFF1Index *dest = c->start_embed<CFF1Index> ();
+    if (!dest) return false;
+    return dest->serialize_header (c, hb_iter (hb_array_t<unsigned> (&top_size, 1)));
+  }
+}
+
+static bool
+_hb_subset_cff1 (const OT::cff1::accelerator_subset_t  &acc,
+		hb_subset_context_t	*c)
+{
+  cff_subset_plan cff_plan;
+
+  if (unlikely (!cff_plan.create (acc, c->plan)))
+  {
+    DEBUG_MSG(SUBSET, nullptr, "Failed to generate a cff subsetting plan.");
+    return false;
+  }
+
+  return _serialize_cff1 (c->serializer, cff_plan, acc, c->plan->num_output_glyphs ());
+}
+
+bool
+hb_subset_cff1 (hb_subset_context_t *c)
+{
+  OT::cff1::accelerator_subset_t acc;
+  acc.init (c->plan->source);
+  bool result = likely (acc.is_valid ()) && _hb_subset_cff1 (acc, c);
+  acc.fini ();
+
+  return result;
+}
+
+
+#endif