src/java.desktop/share/native/libfontmanager/harfbuzz/hb-cff-interp-cs-common.hh
changeset 54232 7c11a7cc7c1d
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.desktop/share/native/libfontmanager/harfbuzz/hb-cff-interp-cs-common.hh	Fri Mar 01 16:59:19 2019 -0800
@@ -0,0 +1,905 @@
+/*
+ * 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
+ */
+#ifndef HB_CFF_INTERP_CS_COMMON_HH
+#define HB_CFF_INTERP_CS_COMMON_HH
+
+#include "hb.hh"
+#include "hb-cff-interp-common.hh"
+
+namespace CFF {
+
+using namespace OT;
+
+enum cs_type_t {
+  CSType_CharString,
+  CSType_GlobalSubr,
+  CSType_LocalSubr
+};
+
+struct call_context_t
+{
+  void init (const byte_str_ref_t substr_=byte_str_ref_t (), cs_type_t type_=CSType_CharString, unsigned int subr_num_=0)
+  {
+    str_ref = substr_;
+    type = type_;
+    subr_num = subr_num_;
+  }
+
+  void fini () {}
+
+  byte_str_ref_t  str_ref;
+  cs_type_t       type;
+  unsigned int    subr_num;
+};
+
+/* call stack */
+const unsigned int kMaxCallLimit = 10;
+struct call_stack_t : stack_t<call_context_t, kMaxCallLimit> {};
+
+template <typename SUBRS>
+struct biased_subrs_t
+{
+  void init (const SUBRS &subrs_)
+  {
+    subrs = &subrs_;
+    unsigned int  nSubrs = get_count ();
+    if (nSubrs < 1240)
+      bias = 107;
+    else if (nSubrs < 33900)
+      bias = 1131;
+    else
+      bias = 32768;
+  }
+
+  void fini () {}
+
+  unsigned int get_count () const { return (subrs == nullptr)? 0: subrs->count; }
+  unsigned int get_bias () const { return bias; }
+
+  byte_str_t operator [] (unsigned int index) const
+  {
+    if (unlikely ((subrs == nullptr) || index >= subrs->count))
+      return Null(byte_str_t);
+    else
+      return (*subrs)[index];
+  }
+
+  protected:
+  unsigned int  bias;
+  const SUBRS   *subrs;
+};
+
+struct point_t
+{
+  void init ()
+  {
+    x.init ();
+    y.init ();
+  }
+
+  void set_int (int _x, int _y)
+  {
+    x.set_int (_x);
+    y.set_int (_y);
+  }
+
+  void move_x (const number_t &dx) { x += dx; }
+  void move_y (const number_t &dy) { y += dy; }
+  void move (const number_t &dx, const number_t &dy) { move_x (dx); move_y (dy); }
+  void move (const point_t &d) { move_x (d.x); move_y (d.y); }
+
+  number_t  x;
+  number_t  y;
+};
+
+template <typename ARG, typename SUBRS>
+struct cs_interp_env_t : interp_env_t<ARG>
+{
+  void init (const byte_str_t &str, const SUBRS &globalSubrs_, const SUBRS &localSubrs_)
+  {
+    interp_env_t<ARG>::init (str);
+
+    context.init (str, CSType_CharString);
+    seen_moveto = true;
+    seen_hintmask = false;
+    hstem_count = 0;
+    vstem_count = 0;
+    hintmask_size = 0;
+    pt.init ();
+    callStack.init ();
+    globalSubrs.init (globalSubrs_);
+    localSubrs.init (localSubrs_);
+  }
+  void fini ()
+  {
+    interp_env_t<ARG>::fini ();
+
+    callStack.fini ();
+    globalSubrs.fini ();
+    localSubrs.fini ();
+  }
+
+  bool in_error () const
+  {
+    return callStack.in_error () || SUPER::in_error ();
+  }
+
+  bool popSubrNum (const biased_subrs_t<SUBRS>& biasedSubrs, unsigned int &subr_num)
+  {
+    int n = SUPER::argStack.pop_int ();
+    n += biasedSubrs.get_bias ();
+    if (unlikely ((n < 0) || ((unsigned int)n >= biasedSubrs.get_count ())))
+      return false;
+
+    subr_num = (unsigned int)n;
+    return true;
+  }
+
+  void callSubr (const biased_subrs_t<SUBRS>& biasedSubrs, cs_type_t type)
+  {
+    unsigned int subr_num;
+
+    if (unlikely (!popSubrNum (biasedSubrs, subr_num)
+                 || callStack.get_count () >= kMaxCallLimit))
+    {
+      SUPER::set_error ();
+      return;
+    }
+    context.str_ref = SUPER::str_ref;
+    callStack.push (context);
+
+    context.init ( biasedSubrs[subr_num], type, subr_num);
+    SUPER::str_ref = context.str_ref;
+  }
+
+  void returnFromSubr ()
+  {
+    if (unlikely (SUPER::str_ref.in_error ()))
+      SUPER::set_error ();
+    context = callStack.pop ();
+    SUPER::str_ref = context.str_ref;
+  }
+
+  void determine_hintmask_size ()
+  {
+    if (!seen_hintmask)
+    {
+      vstem_count += SUPER::argStack.get_count() / 2;
+      hintmask_size = (hstem_count + vstem_count + 7) >> 3;
+      seen_hintmask = true;
+    }
+  }
+
+  void set_endchar (bool endchar_flag_) { endchar_flag = endchar_flag_; }
+  bool is_endchar () const { return endchar_flag; }
+
+  const number_t &get_x () const { return pt.x; }
+  const number_t &get_y () const { return pt.y; }
+  const point_t &get_pt () const { return pt; }
+
+  void moveto (const point_t &pt_ ) { pt = pt_; }
+
+  public:
+  call_context_t   context;
+  bool    endchar_flag;
+  bool    seen_moveto;
+  bool    seen_hintmask;
+
+  unsigned int  hstem_count;
+  unsigned int  vstem_count;
+  unsigned int  hintmask_size;
+  call_stack_t  callStack;
+  biased_subrs_t<SUBRS>   globalSubrs;
+  biased_subrs_t<SUBRS>   localSubrs;
+
+  private:
+  point_t        pt;
+
+  typedef interp_env_t<ARG> SUPER;
+};
+
+template <typename ENV, typename PARAM>
+struct path_procs_null_t
+{
+  static void rmoveto (ENV &env, PARAM& param) {}
+  static void hmoveto (ENV &env, PARAM& param) {}
+  static void vmoveto (ENV &env, PARAM& param) {}
+  static void rlineto (ENV &env, PARAM& param) {}
+  static void hlineto (ENV &env, PARAM& param) {}
+  static void vlineto (ENV &env, PARAM& param) {}
+  static void rrcurveto (ENV &env, PARAM& param) {}
+  static void rcurveline (ENV &env, PARAM& param) {}
+  static void rlinecurve (ENV &env, PARAM& param) {}
+  static void vvcurveto (ENV &env, PARAM& param) {}
+  static void hhcurveto (ENV &env, PARAM& param) {}
+  static void vhcurveto (ENV &env, PARAM& param) {}
+  static void hvcurveto (ENV &env, PARAM& param) {}
+  static void moveto (ENV &env, PARAM& param, const point_t &pt) {}
+  static void line (ENV &env, PARAM& param, const point_t &pt1) {}
+  static void curve (ENV &env, PARAM& param, const point_t &pt1, const point_t &pt2, const point_t &pt3) {}
+  static void hflex (ENV &env, PARAM& param) {}
+  static void flex (ENV &env, PARAM& param) {}
+  static void hflex1 (ENV &env, PARAM& param) {}
+  static void flex1 (ENV &env, PARAM& param) {}
+};
+
+template <typename ARG, typename OPSET, typename ENV, typename PARAM, typename PATH=path_procs_null_t<ENV, PARAM> >
+struct cs_opset_t : opset_t<ARG>
+{
+  static void process_op (op_code_t op, ENV &env, PARAM& param)
+  {
+    switch (op) {
+
+      case OpCode_return:
+        env.returnFromSubr ();
+        break;
+      case OpCode_endchar:
+        OPSET::check_width (op, env, param);
+        env.set_endchar (true);
+        OPSET::flush_args_and_op (op, env, param);
+        break;
+
+      case OpCode_fixedcs:
+        env.argStack.push_fixed_from_substr (env.str_ref);
+        break;
+
+      case OpCode_callsubr:
+        env.callSubr (env.localSubrs, CSType_LocalSubr);
+        break;
+
+      case OpCode_callgsubr:
+        env.callSubr (env.globalSubrs, CSType_GlobalSubr);
+        break;
+
+      case OpCode_hstem:
+      case OpCode_hstemhm:
+        OPSET::check_width (op, env, param);
+        OPSET::process_hstem (op, env, param);
+        break;
+      case OpCode_vstem:
+      case OpCode_vstemhm:
+        OPSET::check_width (op, env, param);
+        OPSET::process_vstem (op, env, param);
+        break;
+      case OpCode_hintmask:
+      case OpCode_cntrmask:
+        OPSET::check_width (op, env, param);
+        OPSET::process_hintmask (op, env, param);
+        break;
+      case OpCode_rmoveto:
+        OPSET::check_width (op, env, param);
+        PATH::rmoveto (env, param);
+        OPSET::process_post_move (op, env, param);
+        break;
+      case OpCode_hmoveto:
+        OPSET::check_width (op, env, param);
+        PATH::hmoveto (env, param);
+        OPSET::process_post_move (op, env, param);
+        break;
+      case OpCode_vmoveto:
+        OPSET::check_width (op, env, param);
+        PATH::vmoveto (env, param);
+        OPSET::process_post_move (op, env, param);
+        break;
+      case OpCode_rlineto:
+        PATH::rlineto (env, param);
+        process_post_path (op, env, param);
+        break;
+      case OpCode_hlineto:
+        PATH::hlineto (env, param);
+        process_post_path (op, env, param);
+        break;
+      case OpCode_vlineto:
+        PATH::vlineto (env, param);
+        process_post_path (op, env, param);
+        break;
+      case OpCode_rrcurveto:
+        PATH::rrcurveto (env, param);
+        process_post_path (op, env, param);
+        break;
+      case OpCode_rcurveline:
+        PATH::rcurveline (env, param);
+        process_post_path (op, env, param);
+        break;
+      case OpCode_rlinecurve:
+        PATH::rlinecurve (env, param);
+        process_post_path (op, env, param);
+        break;
+      case OpCode_vvcurveto:
+        PATH::vvcurveto (env, param);
+        process_post_path (op, env, param);
+        break;
+      case OpCode_hhcurveto:
+        PATH::hhcurveto (env, param);
+        process_post_path (op, env, param);
+        break;
+      case OpCode_vhcurveto:
+        PATH::vhcurveto (env, param);
+        process_post_path (op, env, param);
+        break;
+      case OpCode_hvcurveto:
+        PATH::hvcurveto (env, param);
+        process_post_path (op, env, param);
+        break;
+
+      case OpCode_hflex:
+        PATH::hflex (env, param);
+        OPSET::process_post_flex (op, env, param);
+        break;
+
+      case OpCode_flex:
+        PATH::flex (env, param);
+        OPSET::process_post_flex (op, env, param);
+        break;
+
+      case OpCode_hflex1:
+        PATH::hflex1 (env, param);
+        OPSET::process_post_flex (op, env, param);
+        break;
+
+      case OpCode_flex1:
+        PATH::flex1 (env, param);
+        OPSET::process_post_flex (op, env, param);
+        break;
+
+      default:
+        SUPER::process_op (op, env);
+        break;
+    }
+  }
+
+  static void process_hstem (op_code_t op, ENV &env, PARAM& param)
+  {
+    env.hstem_count += env.argStack.get_count () / 2;
+    OPSET::flush_args_and_op (op, env, param);
+  }
+
+  static void process_vstem (op_code_t op, ENV &env, PARAM& param)
+  {
+    env.vstem_count += env.argStack.get_count () / 2;
+    OPSET::flush_args_and_op (op, env, param);
+  }
+
+  static void process_hintmask (op_code_t op, ENV &env, PARAM& param)
+  {
+    env.determine_hintmask_size ();
+    if (likely (env.str_ref.avail (env.hintmask_size)))
+    {
+      OPSET::flush_hintmask (op, env, param);
+      env.str_ref.inc (env.hintmask_size);
+    }
+  }
+
+  static void process_post_flex (op_code_t op, ENV &env, PARAM& param)
+  {
+    OPSET::flush_args_and_op (op, env, param);
+  }
+
+  static void check_width (op_code_t op, ENV &env, PARAM& param)
+  {}
+
+  static void process_post_move (op_code_t op, ENV &env, PARAM& param)
+  {
+    if (!env.seen_moveto)
+    {
+      env.determine_hintmask_size ();
+      env.seen_moveto = true;
+    }
+    OPSET::flush_args_and_op (op, env, param);
+  }
+
+  static void process_post_path (op_code_t op, ENV &env, PARAM& param)
+  {
+    OPSET::flush_args_and_op (op, env, param);
+  }
+
+  static void flush_args_and_op (op_code_t op, ENV &env, PARAM& param)
+  {
+    OPSET::flush_args (env, param);
+    OPSET::flush_op (op, env, param);
+  }
+
+  static void flush_args (ENV &env, PARAM& param)
+  {
+    env.pop_n_args (env.argStack.get_count ());
+  }
+
+  static void flush_op (op_code_t op, ENV &env, PARAM& param)
+  {
+  }
+
+  static void flush_hintmask (op_code_t op, ENV &env, PARAM& param)
+  {
+    OPSET::flush_args_and_op (op, env, param);
+  }
+
+  static bool is_number_op (op_code_t op)
+  {
+    switch (op)
+    {
+      case OpCode_shortint:
+      case OpCode_fixedcs:
+      case OpCode_TwoBytePosInt0: case OpCode_TwoBytePosInt1:
+      case OpCode_TwoBytePosInt2: case OpCode_TwoBytePosInt3:
+      case OpCode_TwoByteNegInt0: case OpCode_TwoByteNegInt1:
+      case OpCode_TwoByteNegInt2: case OpCode_TwoByteNegInt3:
+        return true;
+
+      default:
+        /* 1-byte integer */
+        return (OpCode_OneByteIntFirst <= op) && (op <= OpCode_OneByteIntLast);
+    }
+  }
+
+  protected:
+  typedef opset_t<ARG>  SUPER;
+};
+
+template <typename PATH, typename ENV, typename PARAM>
+struct path_procs_t
+{
+  static void rmoveto (ENV &env, PARAM& param)
+  {
+    point_t pt1 = env.get_pt ();
+    const number_t &dy = env.pop_arg ();
+    const number_t &dx = env.pop_arg ();
+    pt1.move (dx, dy);
+    PATH::moveto (env, param, pt1);
+  }
+
+  static void hmoveto (ENV &env, PARAM& param)
+  {
+    point_t pt1 = env.get_pt ();
+    pt1.move_x (env.pop_arg ());
+    PATH::moveto (env, param, pt1);
+  }
+
+  static void vmoveto (ENV &env, PARAM& param)
+  {
+    point_t pt1 = env.get_pt ();
+    pt1.move_y (env.pop_arg ());
+    PATH::moveto (env, param, pt1);
+  }
+
+  static void rlineto (ENV &env, PARAM& param)
+  {
+    for (unsigned int i = 0; i + 2 <= env.argStack.get_count (); i += 2)
+    {
+      point_t pt1 = env.get_pt ();
+      pt1.move (env.eval_arg (i), env.eval_arg (i+1));
+      PATH::line (env, param, pt1);
+    }
+  }
+
+  static void hlineto (ENV &env, PARAM& param)
+  {
+    point_t pt1;
+    unsigned int i = 0;
+    for (; i + 2 <= env.argStack.get_count (); i += 2)
+    {
+      pt1 = env.get_pt ();
+      pt1.move_x (env.eval_arg (i));
+      PATH::line (env, param, pt1);
+      pt1.move_y (env.eval_arg (i+1));
+      PATH::line (env, param, pt1);
+    }
+    if (i < env.argStack.get_count ())
+    {
+      pt1 = env.get_pt ();
+      pt1.move_x (env.eval_arg (i));
+      PATH::line (env, param, pt1);
+    }
+  }
+
+  static void vlineto (ENV &env, PARAM& param)
+  {
+    point_t pt1;
+    unsigned int i = 0;
+    for (; i + 2 <= env.argStack.get_count (); i += 2)
+    {
+      pt1 = env.get_pt ();
+      pt1.move_y (env.eval_arg (i));
+      PATH::line (env, param, pt1);
+      pt1.move_x (env.eval_arg (i+1));
+      PATH::line (env, param, pt1);
+    }
+    if (i < env.argStack.get_count ())
+    {
+      pt1 = env.get_pt ();
+      pt1.move_y (env.eval_arg (i));
+      PATH::line (env, param, pt1);
+    }
+  }
+
+  static void rrcurveto (ENV &env, PARAM& param)
+  {
+    for (unsigned int i = 0; i + 6 <= env.argStack.get_count (); i += 6)
+    {
+      point_t pt1 = env.get_pt ();
+      pt1.move (env.eval_arg (i), env.eval_arg (i+1));
+      point_t pt2 = pt1;
+      pt2.move (env.eval_arg (i+2), env.eval_arg (i+3));
+      point_t pt3 = pt2;
+      pt3.move (env.eval_arg (i+4), env.eval_arg (i+5));
+      PATH::curve (env, param, pt1, pt2, pt3);
+    }
+  }
+
+  static void rcurveline (ENV &env, PARAM& param)
+  {
+    unsigned int i = 0;
+    for (; i + 6 <= env.argStack.get_count (); i += 6)
+    {
+      point_t pt1 = env.get_pt ();
+      pt1.move (env.eval_arg (i), env.eval_arg (i+1));
+      point_t pt2 = pt1;
+      pt2.move (env.eval_arg (i+2), env.eval_arg (i+3));
+      point_t pt3 = pt2;
+      pt3.move (env.eval_arg (i+4), env.eval_arg (i+5));
+      PATH::curve (env, param, pt1, pt2, pt3);
+    }
+    for (; i + 2 <= env.argStack.get_count (); i += 2)
+    {
+      point_t pt1 = env.get_pt ();
+      pt1.move (env.eval_arg (i), env.eval_arg (i+1));
+      PATH::line (env, param, pt1);
+    }
+  }
+
+  static void rlinecurve (ENV &env, PARAM& param)
+  {
+    unsigned int i = 0;
+    unsigned int line_limit = (env.argStack.get_count () % 6);
+    for (; i + 2 <= line_limit; i += 2)
+    {
+      point_t pt1 = env.get_pt ();
+      pt1.move (env.eval_arg (i), env.eval_arg (i+1));
+      PATH::line (env, param, pt1);
+    }
+    for (; i + 6 <= env.argStack.get_count (); i += 6)
+    {
+      point_t pt1 = env.get_pt ();
+      pt1.move (env.eval_arg (i), env.eval_arg (i+1));
+      point_t pt2 = pt1;
+      pt2.move (env.eval_arg (i+2), env.eval_arg (i+3));
+      point_t pt3 = pt2;
+      pt3.move (env.eval_arg (i+4), env.eval_arg (i+5));
+      PATH::curve (env, param, pt1, pt2, pt3);
+    }
+  }
+
+  static void vvcurveto (ENV &env, PARAM& param)
+  {
+    unsigned int i = 0;
+    point_t pt1 = env.get_pt ();
+    if ((env.argStack.get_count () & 1) != 0)
+      pt1.move_x (env.eval_arg (i++));
+    for (; i + 4 <= env.argStack.get_count (); i += 4)
+    {
+      pt1.move_y (env.eval_arg (i));
+      point_t pt2 = pt1;
+      pt2.move (env.eval_arg (i+1), env.eval_arg (i+2));
+      point_t pt3 = pt2;
+      pt3.move_y (env.eval_arg (i+3));
+      PATH::curve (env, param, pt1, pt2, pt3);
+      pt1 = env.get_pt ();
+    }
+  }
+
+  static void hhcurveto (ENV &env, PARAM& param)
+  {
+    unsigned int i = 0;
+    point_t pt1 = env.get_pt ();
+    if ((env.argStack.get_count () & 1) != 0)
+      pt1.move_y (env.eval_arg (i++));
+    for (; i + 4 <= env.argStack.get_count (); i += 4)
+    {
+      pt1.move_x (env.eval_arg (i));
+      point_t pt2 = pt1;
+      pt2.move (env.eval_arg (i+1), env.eval_arg (i+2));
+      point_t pt3 = pt2;
+      pt3.move_x (env.eval_arg (i+3));
+      PATH::curve (env, param, pt1, pt2, pt3);
+      pt1 = env.get_pt ();
+    }
+  }
+
+  static void vhcurveto (ENV &env, PARAM& param)
+  {
+    point_t pt1, pt2, pt3;
+    unsigned int i = 0;
+    if ((env.argStack.get_count () % 8) >= 4)
+    {
+      point_t pt1 = env.get_pt ();
+      pt1.move_y (env.eval_arg (i));
+      point_t pt2 = pt1;
+      pt2.move (env.eval_arg (i+1), env.eval_arg (i+2));
+      point_t pt3 = pt2;
+      pt3.move_x (env.eval_arg (i+3));
+      i += 4;
+
+      for (; i + 8 <= env.argStack.get_count (); i += 8)
+      {
+        PATH::curve (env, param, pt1, pt2, pt3);
+        pt1 = env.get_pt ();
+        pt1.move_x (env.eval_arg (i));
+        pt2 = pt1;
+        pt2.move (env.eval_arg (i+1), env.eval_arg (i+2));
+        pt3 = pt2;
+        pt3.move_y (env.eval_arg (i+3));
+        PATH::curve (env, param, pt1, pt2, pt3);
+
+        pt1 = pt3;
+        pt1.move_y (env.eval_arg (i+4));
+        pt2 = pt1;
+        pt2.move (env.eval_arg (i+5), env.eval_arg (i+6));
+        pt3 = pt2;
+        pt3.move_x (env.eval_arg (i+7));
+      }
+      if (i < env.argStack.get_count ())
+        pt3.move_y (env.eval_arg (i));
+      PATH::curve (env, param, pt1, pt2, pt3);
+    }
+    else
+    {
+      for (; i + 8 <= env.argStack.get_count (); i += 8)
+      {
+        pt1 = env.get_pt ();
+        pt1.move_y (env.eval_arg (i));
+        pt2 = pt1;
+        pt2.move (env.eval_arg (i+1), env.eval_arg (i+2));
+        pt3 = pt2;
+        pt3.move_x (env.eval_arg (i+3));
+        PATH::curve (env, param, pt1, pt2, pt3);
+
+        pt1 = pt3;
+        pt1.move_x (env.eval_arg (i+4));
+        pt2 = pt1;
+        pt2.move (env.eval_arg (i+5), env.eval_arg (i+6));
+        pt3 = pt2;
+        pt3.move_y (env.eval_arg (i+7));
+        if ((env.argStack.get_count () - i < 16) && ((env.argStack.get_count () & 1) != 0))
+          pt3.move_x (env.eval_arg (i+8));
+        PATH::curve (env, param, pt1, pt2, pt3);
+      }
+    }
+  }
+
+  static void hvcurveto (ENV &env, PARAM& param)
+  {
+    point_t pt1, pt2, pt3;
+    unsigned int i = 0;
+    if ((env.argStack.get_count () % 8) >= 4)
+    {
+      point_t pt1 = env.get_pt ();
+      pt1.move_x (env.eval_arg (i));
+      point_t pt2 = pt1;
+      pt2.move (env.eval_arg (i+1), env.eval_arg (i+2));
+      point_t pt3 = pt2;
+      pt3.move_y (env.eval_arg (i+3));
+      i += 4;
+
+      for (; i + 8 <= env.argStack.get_count (); i += 8)
+      {
+        PATH::curve (env, param, pt1, pt2, pt3);
+        pt1 = env.get_pt ();
+        pt1.move_y (env.eval_arg (i));
+        pt2 = pt1;
+        pt2.move (env.eval_arg (i+1), env.eval_arg (i+2));
+        pt3 = pt2;
+        pt3.move_x (env.eval_arg (i+3));
+        PATH::curve (env, param, pt1, pt2, pt3);
+
+        pt1 = pt3;
+        pt1.move_x (env.eval_arg (i+4));
+        pt2 = pt1;
+        pt2.move (env.eval_arg (i+5), env.eval_arg (i+6));
+        pt3 = pt2;
+        pt3.move_y (env.eval_arg (i+7));
+      }
+      if (i < env.argStack.get_count ())
+        pt3.move_x (env.eval_arg (i));
+      PATH::curve (env, param, pt1, pt2, pt3);
+    }
+    else
+    {
+      for (; i + 8 <= env.argStack.get_count (); i += 8)
+      {
+        pt1 = env.get_pt ();
+        pt1.move_x (env.eval_arg (i));
+        pt2 = pt1;
+        pt2.move (env.eval_arg (i+1), env.eval_arg (i+2));
+        pt3 = pt2;
+        pt3.move_y (env.eval_arg (i+3));
+        PATH::curve (env, param, pt1, pt2, pt3);
+
+        pt1 = pt3;
+        pt1.move_y (env.eval_arg (i+4));
+        pt2 = pt1;
+        pt2.move (env.eval_arg (i+5), env.eval_arg (i+6));
+        pt3 = pt2;
+        pt3.move_x (env.eval_arg (i+7));
+        if ((env.argStack.get_count () - i < 16) && ((env.argStack.get_count () & 1) != 0))
+          pt3.move_y (env.eval_arg (i+8));
+        PATH::curve (env, param, pt1, pt2, pt3);
+      }
+    }
+  }
+
+  /* default actions to be overridden */
+  static void moveto (ENV &env, PARAM& param, const point_t &pt)
+  { env.moveto (pt); }
+
+  static void line (ENV &env, PARAM& param, const point_t &pt1)
+  { PATH::moveto (env, param, pt1); }
+
+  static void curve (ENV &env, PARAM& param, const point_t &pt1, const point_t &pt2, const point_t &pt3)
+  { PATH::moveto (env, param, pt3); }
+
+  static void hflex (ENV &env, PARAM& param)
+  {
+    if (likely (env.argStack.get_count () == 7))
+    {
+      point_t pt1 = env.get_pt ();
+      pt1.move_x (env.eval_arg (0));
+      point_t pt2 = pt1;
+      pt2.move (env.eval_arg (1), env.eval_arg (2));
+      point_t pt3 = pt2;
+      pt3.move_x (env.eval_arg (3));
+      point_t pt4 = pt3;
+      pt4.move_x (env.eval_arg (4));
+      point_t pt5 = pt4;
+      pt5.move_x (env.eval_arg (5));
+      pt5.y = pt1.y;
+      point_t pt6 = pt5;
+      pt6.move_x (env.eval_arg (6));
+
+      curve2 (env, param, pt1, pt2, pt3, pt4, pt5, pt6);
+    }
+    else
+      env.set_error ();
+  }
+
+  static void flex (ENV &env, PARAM& param)
+  {
+    if (likely (env.argStack.get_count () == 13))
+    {
+      point_t pt1 = env.get_pt ();
+      pt1.move (env.eval_arg (0), env.eval_arg (1));
+      point_t pt2 = pt1;
+      pt2.move (env.eval_arg (2), env.eval_arg (3));
+      point_t pt3 = pt2;
+      pt3.move (env.eval_arg (4), env.eval_arg (5));
+      point_t pt4 = pt3;
+      pt4.move (env.eval_arg (6), env.eval_arg (7));
+      point_t pt5 = pt4;
+      pt5.move (env.eval_arg (8), env.eval_arg (9));
+      point_t pt6 = pt5;
+      pt6.move (env.eval_arg (10), env.eval_arg (11));
+
+      curve2 (env, param, pt1, pt2, pt3, pt4, pt5, pt6);
+    }
+    else
+      env.set_error ();
+  }
+
+  static void hflex1 (ENV &env, PARAM& param)
+  {
+    if (likely (env.argStack.get_count () == 9))
+    {
+      point_t pt1 = env.get_pt ();
+      pt1.move (env.eval_arg (0), env.eval_arg (1));
+      point_t pt2 = pt1;
+      pt2.move (env.eval_arg (2), env.eval_arg (3));
+      point_t pt3 = pt2;
+      pt3.move_x (env.eval_arg (4));
+      point_t pt4 = pt3;
+      pt4.move_x (env.eval_arg (5));
+      point_t pt5 = pt4;
+      pt5.move (env.eval_arg (6), env.eval_arg (7));
+      point_t pt6 = pt5;
+      pt6.move_x (env.eval_arg (8));
+      pt6.y = env.get_pt ().y;
+
+      curve2 (env, param, pt1, pt2, pt3, pt4, pt5, pt6);
+    }
+    else
+      env.set_error ();
+  }
+
+  static void flex1 (ENV &env, PARAM& param)
+  {
+    if (likely (env.argStack.get_count () == 11))
+    {
+      point_t d;
+      d.init ();
+      for (unsigned int i = 0; i < 10; i += 2)
+        d.move (env.eval_arg (i), env.eval_arg (i+1));
+
+      point_t pt1 = env.get_pt ();
+      pt1.move (env.eval_arg (0), env.eval_arg (1));
+      point_t pt2 = pt1;
+      pt2.move (env.eval_arg (2), env.eval_arg (3));
+      point_t pt3 = pt2;
+      pt3.move (env.eval_arg (4), env.eval_arg (5));
+      point_t pt4 = pt3;
+      pt4.move (env.eval_arg (6), env.eval_arg (7));
+      point_t pt5 = pt4;
+      pt5.move (env.eval_arg (8), env.eval_arg (9));
+      point_t pt6 = pt5;
+
+      if (fabs (d.x.to_real ()) > fabs (d.y.to_real ()))
+      {
+        pt6.move_x (env.eval_arg (10));
+        pt6.y = env.get_pt ().y;
+      }
+      else
+      {
+        pt6.x = env.get_pt ().x;
+        pt6.move_y (env.eval_arg (10));
+      }
+
+      curve2 (env, param, pt1, pt2, pt3, pt4, pt5, pt6);
+    }
+    else
+      env.set_error ();
+  }
+
+  protected:
+  static void curve2 (ENV &env, PARAM& param,
+                      const point_t &pt1, const point_t &pt2, const point_t &pt3,
+                      const point_t &pt4, const point_t &pt5, const point_t &pt6)
+  {
+    PATH::curve (env, param, pt1, pt2, pt3);
+    PATH::curve (env, param, pt4, pt5, pt6);
+  }
+};
+
+template <typename ENV, typename OPSET, typename PARAM>
+struct cs_interpreter_t : interpreter_t<ENV>
+{
+  bool interpret (PARAM& param)
+  {
+    SUPER::env.set_endchar (false);
+
+    for (;;) {
+      OPSET::process_op (SUPER::env.fetch_op (), SUPER::env, param);
+      if (unlikely (SUPER::env.in_error ()))
+        return false;
+      if (SUPER::env.is_endchar ())
+        break;
+    }
+
+    return true;
+  }
+
+  private:
+  typedef interpreter_t<ENV> SUPER;
+};
+
+} /* namespace CFF */
+
+#endif /* HB_CFF_INTERP_CS_COMMON_HH */