Update to Harfbuzz 2.6.4

Quite a big change since it has been several years since
the last update. This drops the Harfbuzz source on top
of the existing code in Qt, and does the following
additional changes:

1. Deletes old source files that have been removed upstream
(everything named foo-private.hh is now renamed to just
foo.hh for instance).

2. Added a header guard to config.h because it may be
double-included.

3. Implement a memory barrier needed by hb-atomic.hh.

4. Changed the signature of hb_atomic_int_impl_add()
to take a pointer to match new upstream.

5. Updated .pro file to include new files and removed
old.

6. Updated qt_attribution.json

7. No longer disable deprecated APIs since
hb_ot_tags_from_script() is now deprecated and is used
from Qt code.

8. Updated and applied the patch in patches/ for CoreText.

9. Updated tst_qtextscriptengine::thaiWithZWJ() according to
changes in Harfbuzz and disabled it for system-harfbuzz,
since this may be an older version of harfbuzz depending on
the system.

Fixes: QTBUG-79606
Change-Id: I3f057a43ff44ee416628b75ef12fb1a221f31910
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

1 files changed, 906 insertions, 0 deletions

diff --git a/src/3rdparty/harfbuzz-ng/src/hb-cff-interp-cs-common.hh b/src/3rdparty/harfbuzz-ng/src/hb-cff-interp-cs-common.hh
new file mode 100644
index 0000000000..d9ad4d0d69
--- /dev/null
+++ b/src/3rdparty/harfbuzz-ng/src/hb-cff-interp-cs-common.hh
@@ -0,0 +1,906 @@
+/*
+ * 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 : cff_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 pop_subr_num (const biased_subrs_t<SUBRS>& biasedSubrs, unsigned int &subr_num)
+  {
+    subr_num = 0;
+    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 call_subr (const biased_subrs_t<SUBRS>& biasedSubrs, cs_type_t type)
+  {
+    unsigned int subr_num = 0;
+
+    if (unlikely (!pop_subr_num (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 return_from_subr ()
+  {
+    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.return_from_subr ();
+	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.call_subr (env.localSubrs, CSType_LocalSubr);
+	break;
+
+      case OpCode_callgsubr:
+	env.call_subr (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 */