hb-cff-interp-common.hh

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/*
 * 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_COMMON_HH
#define HB_CFF_INTERP_COMMON_HH
 
namespace CFF {
 
using namespace OT;
 
typedef unsigned int op_code_t;
 
 
/* === Dict operators === */
 
/* One byte operators (0-31) */
#define OpCode_version        0 /* CFF Top */
#define OpCode_Notice         1 /* CFF Top */
#define OpCode_FullName       2 /* CFF Top */
#define OpCode_FamilyName     3 /* CFF Top */
#define OpCode_Weight         4 /* CFF Top */
#define OpCode_FontBBox       5 /* CFF Top */
#define OpCode_BlueValues     6 /* CFF Private, CFF2 Private */
#define OpCode_OtherBlues     7 /* CFF Private, CFF2 Private */
#define OpCode_FamilyBlues    8 /* CFF Private, CFF2 Private */
#define OpCode_FamilyOtherBlues   9 /* CFF Private, CFF2 Private */
#define OpCode_StdHW         10 /* CFF Private, CFF2 Private */
#define OpCode_StdVW         11 /* CFF Private, CFF2 Private */
#define OpCode_escape        12 /* All. Shared with CS */
#define OpCode_UniqueID      13 /* CFF Top */
#define OpCode_XUID      14 /* CFF Top */
#define OpCode_charset       15 /* CFF Top (0) */
#define OpCode_Encoding      16 /* CFF Top (0) */
#define OpCode_CharStrings   17 /* CFF Top, CFF2 Top */
#define OpCode_Private       18 /* CFF Top, CFF2 FD */
#define OpCode_Subrs         19 /* CFF Private, CFF2 Private */
#define OpCode_defaultWidthX     20 /* CFF Private (0) */
#define OpCode_nominalWidthX     21 /* CFF Private (0) */
#define OpCode_vsindexdict   22 /* CFF2 Private/CS */
#define OpCode_blenddict     23 /* CFF2 Private/CS */
#define OpCode_vstore        24 /* CFF2 Top */
#define OpCode_reserved25    25
#define OpCode_reserved26    26
#define OpCode_reserved27    27
 
/* Numbers */
#define OpCode_shortint      28 /* 16-bit integer, All */
#define OpCode_longintdict   29 /* 32-bit integer, All */
#define OpCode_BCD       30 /* Real number, CFF2 Top/FD */
#define OpCode_reserved31    31
 
/* 1-byte integers */
#define OpCode_OneByteIntFirst   32 /* All. beginning of the range of first byte ints */
#define OpCode_OneByteIntLast   246 /* All. ending of the range of first byte int */
 
/* 2-byte integers */
#define OpCode_TwoBytePosInt0   247 /* All. first byte of two byte positive int (+108 to +1131) */
#define OpCode_TwoBytePosInt1   248
#define OpCode_TwoBytePosInt2   249
#define OpCode_TwoBytePosInt3   250
 
#define OpCode_TwoByteNegInt0   251 /* All. first byte of two byte negative int (-1131 to -108) */
#define OpCode_TwoByteNegInt1   252
#define OpCode_TwoByteNegInt2   253
#define OpCode_TwoByteNegInt3   254
 
/* Two byte escape operators 12, (0-41) */
#define OpCode_ESC_Base     256
#define Make_OpCode_ESC(byte2)  ((op_code_t)(OpCode_ESC_Base + (byte2)))
 
inline op_code_t Unmake_OpCode_ESC (op_code_t op)  { return (op_code_t)(op - OpCode_ESC_Base); }
inline bool Is_OpCode_ESC (op_code_t op) { return op >= OpCode_ESC_Base; }
inline unsigned int OpCode_Size (op_code_t op) { return Is_OpCode_ESC (op) ? 2: 1; }
 
#define OpCode_Copyright    Make_OpCode_ESC(0) /* CFF Top */
#define OpCode_isFixedPitch Make_OpCode_ESC(1) /* CFF Top (false) */
#define OpCode_ItalicAngle  Make_OpCode_ESC(2) /* CFF Top (0) */
#define OpCode_UnderlinePosition Make_OpCode_ESC(3) /* CFF Top (-100) */
#define OpCode_UnderlineThickness Make_OpCode_ESC(4) /* CFF Top (50) */
#define OpCode_PaintType    Make_OpCode_ESC(5) /* CFF Top (0) */
#define OpCode_CharstringType   Make_OpCode_ESC(6) /* CFF Top (2) */
#define OpCode_FontMatrix   Make_OpCode_ESC(7) /* CFF Top, CFF2 Top (.001 0 0 .001 0 0)*/
#define OpCode_StrokeWidth  Make_OpCode_ESC(8) /* CFF Top (0) */
#define OpCode_BlueScale    Make_OpCode_ESC(9) /* CFF Private, CFF2 Private (0.039625) */
#define OpCode_BlueShift    Make_OpCode_ESC(10) /* CFF Private, CFF2 Private (7) */
#define OpCode_BlueFuzz     Make_OpCode_ESC(11) /* CFF Private, CFF2 Private (1) */
#define OpCode_StemSnapH    Make_OpCode_ESC(12) /* CFF Private, CFF2 Private */
#define OpCode_StemSnapV    Make_OpCode_ESC(13) /* CFF Private, CFF2 Private */
#define OpCode_ForceBold    Make_OpCode_ESC(14) /* CFF Private (false) */
#define OpCode_reservedESC15    Make_OpCode_ESC(15)
#define OpCode_reservedESC16    Make_OpCode_ESC(16)
#define OpCode_LanguageGroup    Make_OpCode_ESC(17) /* CFF Private, CFF2 Private (0) */
#define OpCode_ExpansionFactor  Make_OpCode_ESC(18) /* CFF Private, CFF2 Private (0.06) */
#define OpCode_initialRandomSeed Make_OpCode_ESC(19) /* CFF Private (0) */
#define OpCode_SyntheticBase    Make_OpCode_ESC(20) /* CFF Top */
#define OpCode_PostScript   Make_OpCode_ESC(21) /* CFF Top */
#define OpCode_BaseFontName Make_OpCode_ESC(22) /* CFF Top */
#define OpCode_BaseFontBlend    Make_OpCode_ESC(23) /* CFF Top */
#define OpCode_reservedESC24    Make_OpCode_ESC(24)
#define OpCode_reservedESC25    Make_OpCode_ESC(25)
#define OpCode_reservedESC26    Make_OpCode_ESC(26)
#define OpCode_reservedESC27    Make_OpCode_ESC(27)
#define OpCode_reservedESC28    Make_OpCode_ESC(28)
#define OpCode_reservedESC29    Make_OpCode_ESC(29)
#define OpCode_ROS      Make_OpCode_ESC(30) /* CFF Top_CID */
#define OpCode_CIDFontVersion   Make_OpCode_ESC(31) /* CFF Top_CID (0) */
#define OpCode_CIDFontRevision  Make_OpCode_ESC(32) /* CFF Top_CID (0) */
#define OpCode_CIDFontType  Make_OpCode_ESC(33) /* CFF Top_CID (0) */
#define OpCode_CIDCount     Make_OpCode_ESC(34) /* CFF Top_CID (8720) */
#define OpCode_UIDBase      Make_OpCode_ESC(35) /* CFF Top_CID */
#define OpCode_FDArray      Make_OpCode_ESC(36) /* CFF Top_CID, CFF2 Top */
#define OpCode_FDSelect     Make_OpCode_ESC(37) /* CFF Top_CID, CFF2 Top */
#define OpCode_FontName     Make_OpCode_ESC(38) /* CFF Top_CID */
 
 
/* === CharString operators === */
 
#define OpCode_hstem          1 /* CFF, CFF2 */
#define OpCode_Reserved2      2
#define OpCode_vstem          3 /* CFF, CFF2 */
#define OpCode_vmoveto        4 /* CFF, CFF2 */
#define OpCode_rlineto        5 /* CFF, CFF2 */
#define OpCode_hlineto        6 /* CFF, CFF2 */
#define OpCode_vlineto        7 /* CFF, CFF2 */
#define OpCode_rrcurveto      8 /* CFF, CFF2 */
#define OpCode_Reserved9      9
#define OpCode_callsubr      10 /* CFF, CFF2 */
#define OpCode_return        11 /* CFF */
//#define OpCode_escape      12 /* CFF, CFF2 */
#define OpCode_Reserved13    13
#define OpCode_endchar       14 /* CFF */
#define OpCode_vsindexcs     15 /* CFF2 */
#define OpCode_blendcs       16 /* CFF2 */
#define OpCode_Reserved17    17
#define OpCode_hstemhm       18 /* CFF, CFF2 */
#define OpCode_hintmask      19 /* CFF, CFF2 */
#define OpCode_cntrmask      20 /* CFF, CFF2 */
#define OpCode_rmoveto       21 /* CFF, CFF2 */
#define OpCode_hmoveto       22 /* CFF, CFF2 */
#define OpCode_vstemhm       23 /* CFF, CFF2 */
#define OpCode_rcurveline    24 /* CFF, CFF2 */
#define OpCode_rlinecurve    25 /* CFF, CFF2 */
#define OpCode_vvcurveto     26 /* CFF, CFF2 */
#define OpCode_hhcurveto     27 /* CFF, CFF2 */
//#define OpCode_shortint    28 /* CFF, CFF2 */
#define OpCode_callgsubr     29 /* CFF, CFF2 */
#define OpCode_vhcurveto     30 /* CFF, CFF2 */
#define OpCode_hvcurveto     31 /* CFF, CFF2 */
 
#define OpCode_fixedcs      255 /* 32-bit fixed */
 
/* Two byte escape operators 12, (0-41) */
#define OpCode_dotsection   Make_OpCode_ESC(0) /* CFF (obsoleted) */
#define OpCode_ReservedESC1 Make_OpCode_ESC(1)
#define OpCode_ReservedESC2 Make_OpCode_ESC(2)
#define OpCode_and      Make_OpCode_ESC(3) /* CFF */
#define OpCode_or       Make_OpCode_ESC(4) /* CFF */
#define OpCode_not      Make_OpCode_ESC(5) /* CFF */
#define OpCode_ReservedESC6 Make_OpCode_ESC(6)
#define OpCode_ReservedESC7 Make_OpCode_ESC(7)
#define OpCode_ReservedESC8 Make_OpCode_ESC(8)
#define OpCode_abs      Make_OpCode_ESC(9) /* CFF */
#define OpCode_add      Make_OpCode_ESC(10) /* CFF */
#define OpCode_sub      Make_OpCode_ESC(11) /* CFF */
#define OpCode_div      Make_OpCode_ESC(12) /* CFF */
#define OpCode_ReservedESC13    Make_OpCode_ESC(13)
#define OpCode_neg      Make_OpCode_ESC(14) /* CFF */
#define OpCode_eq       Make_OpCode_ESC(15) /* CFF */
#define OpCode_ReservedESC16    Make_OpCode_ESC(16)
#define OpCode_ReservedESC17    Make_OpCode_ESC(17)
#define OpCode_drop     Make_OpCode_ESC(18) /* CFF */
#define OpCode_ReservedESC19    Make_OpCode_ESC(19)
#define OpCode_put      Make_OpCode_ESC(20) /* CFF */
#define OpCode_get      Make_OpCode_ESC(21) /* CFF */
#define OpCode_ifelse       Make_OpCode_ESC(22) /* CFF */
#define OpCode_random       Make_OpCode_ESC(23) /* CFF */
#define OpCode_mul      Make_OpCode_ESC(24) /* CFF */
//#define OpCode_reservedESC25  Make_OpCode_ESC(25)
#define OpCode_sqrt     Make_OpCode_ESC(26) /* CFF */
#define OpCode_dup      Make_OpCode_ESC(27) /* CFF */
#define OpCode_exch     Make_OpCode_ESC(28) /* CFF */
#define OpCode_index        Make_OpCode_ESC(29) /* CFF */
#define OpCode_roll     Make_OpCode_ESC(30) /* CFF */
#define OpCode_reservedESC31    Make_OpCode_ESC(31)
#define OpCode_reservedESC32    Make_OpCode_ESC(32)
#define OpCode_reservedESC33    Make_OpCode_ESC(33)
#define OpCode_hflex        Make_OpCode_ESC(34) /* CFF, CFF2 */
#define OpCode_flex     Make_OpCode_ESC(35) /* CFF, CFF2 */
#define OpCode_hflex1       Make_OpCode_ESC(36) /* CFF, CFF2 */
#define OpCode_flex1        Make_OpCode_ESC(37) /* CFF, CFF2 */
 
 
#define OpCode_Invalid      0xFFFFu
 
 
struct number_t
{
  void set_int (int v)       { value = v; }
  int to_int () const        { return value; }
 
  void set_fixed (int32_t v) { value = v / 65536.0; }
  int32_t to_fixed () const  { return value * 65536.0; }
 
  void set_real (double v)   { value = v; }
  double to_real () const    { return value; }
 
  bool in_int_range () const
  { return ((double) (int16_t) to_int () == value); }
 
  bool operator >  (const number_t &n) const { return value > n.to_real (); }
  bool operator <  (const number_t &n) const { return n > *this; }
  bool operator >= (const number_t &n) const { return !(*this < n); }
  bool operator <= (const number_t &n) const { return !(*this > n); }
 
  const number_t &operator += (const number_t &n)
  {
    set_real (to_real () + n.to_real ());
 
    return *this;
  }
 
  protected:
  double value = 0.;
};
 
/* byte string */
struct UnsizedByteStr : UnsizedArrayOf <HBUINT8>
{
  // encode 2-byte int (Dict/CharString) or 4-byte int (Dict)
  template <typename T, typename V>
  static bool serialize_int (hb_serialize_context_t *c, op_code_t intOp, V value)
  {
    TRACE_SERIALIZE (this);
 
    HBUINT8 *p = c->allocate_size<HBUINT8> (1);
    if (unlikely (!p)) return_trace (false);
    *p = intOp;
 
    T *ip = c->allocate_size<T> (T::static_size);
    if (unlikely (!ip)) return_trace (false);
    return_trace (c->check_assign (*ip, value, HB_SERIALIZE_ERROR_INT_OVERFLOW));
  }
 
  template <typename V>
  static bool serialize_int4 (hb_serialize_context_t *c, V value)
  { return serialize_int<HBINT32> (c, OpCode_longintdict, value); }
 
  template <typename V>
  static bool serialize_int2 (hb_serialize_context_t *c, V value)
  { return serialize_int<HBINT16> (c, OpCode_shortint, value); }
 
  /* Defining null_size allows a Null object may be created. Should be safe because:
   * A descendent struct Dict uses a Null pointer to indicate a missing table,
   * checked before access.
   * byte_str_t, a wrapper struct pairing a byte pointer along with its length, always
   * checks the length before access. A Null pointer is used as the initial pointer
   * along with zero length by the default ctor.
   */
  DEFINE_SIZE_MIN(0);
};
 
/* Holder of a section of byte string within a CFFIndex entry */
struct byte_str_t : hb_ubytes_t
{
  byte_str_t ()
    : hb_ubytes_t () {}
  byte_str_t (const UnsizedByteStr& s, unsigned int l)
    : hb_ubytes_t ((const unsigned char*)&s, l) {}
  byte_str_t (const unsigned char *s, unsigned int l)
    : hb_ubytes_t (s, l) {}
  byte_str_t (const hb_ubytes_t &ub)    /* conversion from hb_ubytes_t */
    : hb_ubytes_t (ub) {}
 
  /* sub-string */
  byte_str_t sub_str (unsigned int offset, unsigned int len_) const
  { return byte_str_t (hb_ubytes_t::sub_array (offset, len_)); }
 
  bool check_limit (unsigned int offset, unsigned int count) const
  { return (offset + count <= length); }
};
 
/* A byte string associated with the current offset and an error condition */
struct byte_str_ref_t
{
  byte_str_ref_t () { init (); }
 
  void init ()
  {
    str = byte_str_t ();
    offset = 0;
    error = false;
  }
 
  void fini () {}
 
  byte_str_ref_t (const byte_str_t &str_, unsigned int offset_ = 0)
    : str (str_), offset (offset_), error (false) {}
 
  void reset (const byte_str_t &str_, unsigned int offset_ = 0)
  {
    str = str_;
    offset = offset_;
    error = false;
  }
 
  const unsigned char& operator [] (int i) {
    if (unlikely ((unsigned int) (offset + i) >= str.length))
    {
      set_error ();
      return Null (unsigned char);
    }
    return str[offset + i];
  }
 
  /* Conversion to byte_str_t */
  operator byte_str_t () const { return str.sub_str (offset, str.length - offset); }
 
  byte_str_t sub_str (unsigned int offset_, unsigned int len_) const
  { return str.sub_str (offset_, len_); }
 
  bool avail (unsigned int count=1) const
  { return (!in_error () && str.check_limit (offset, count)); }
  void inc (unsigned int count=1)
  {
    if (likely (!in_error () && (offset <= str.length) && (offset + count <= str.length)))
    {
      offset += count;
    }
    else
    {
      offset = str.length;
      set_error ();
    }
  }
 
  void set_error ()      { error = true; }
  bool in_error () const { return error; }
 
  byte_str_t       str;
  unsigned int  offset; /* beginning of the sub-string within str */
 
  protected:
  bool    error;
};
 
typedef hb_vector_t<byte_str_t> byte_str_array_t;
 
/* stack */
template <typename ELEM, int LIMIT>
struct cff_stack_t
{
  void init ()
  {
    error = false;
    count = 0;
    elements.init ();
    elements.resize (kSizeLimit);
  }
  void fini () { elements.fini (); }
 
  ELEM& operator [] (unsigned int i)
  {
    if (unlikely (i >= count)) set_error ();
    return elements[i];
  }
 
  void push (const ELEM &v)
  {
    if (likely (count < elements.length))
      elements[count++] = v;
    else
      set_error ();
  }
  ELEM &push ()
  {
    if (likely (count < elements.length))
      return elements[count++];
    else
    {
      set_error ();
      return Crap (ELEM);
    }
  }
 
  ELEM& pop ()
  {
    if (likely (count > 0))
      return elements[--count];
    else
    {
      set_error ();
      return Crap (ELEM);
    }
  }
  void pop (unsigned int n)
  {
    if (likely (count >= n))
      count -= n;
    else
      set_error ();
  }
 
  const ELEM& peek ()
  {
    if (unlikely (count < 0))
    {
      set_error ();
      return Null (ELEM);
    }
    return elements[count - 1];
  }
 
  void unpop ()
  {
    if (likely (count < elements.length))
      count++;
    else
      set_error ();
  }
 
  void clear () { count = 0; }
 
  bool in_error () const { return (error || elements.in_error ()); }
  void set_error ()      { error = true; }
 
  unsigned int get_count () const { return count; }
  bool is_empty () const          { return !count; }
 
  static constexpr unsigned kSizeLimit = LIMIT;
 
  protected:
  bool error;
  unsigned int count;
  hb_vector_t<ELEM> elements;
};
 
/* argument stack */
template <typename ARG=number_t>
struct arg_stack_t : cff_stack_t<ARG, 513>
{
  void push_int (int v)
  {
    ARG &n = S::push ();
    n.set_int (v);
  }
 
  void push_fixed (int32_t v)
  {
    ARG &n = S::push ();
    n.set_fixed (v);
  }
 
  void push_real (double v)
  {
    ARG &n = S::push ();
    n.set_real (v);
  }
 
  ARG& pop_num () { return this->pop (); }
 
  int pop_int ()  { return this->pop ().to_int (); }
 
  unsigned int pop_uint ()
  {
    int i = pop_int ();
    if (unlikely (i < 0))
    {
      i = 0;
      S::set_error ();
    }
    return (unsigned) i;
  }
 
  void push_longint_from_substr (byte_str_ref_t& str_ref)
  {
    push_int ((str_ref[0] << 24) | (str_ref[1] << 16) | (str_ref[2] << 8) | (str_ref[3]));
    str_ref.inc (4);
  }
 
  bool push_fixed_from_substr (byte_str_ref_t& str_ref)
  {
    if (unlikely (!str_ref.avail (4)))
      return false;
    push_fixed ((int32_t)*(const HBUINT32*)&str_ref[0]);
    str_ref.inc (4);
    return true;
  }
 
  hb_array_t<const ARG> get_subarray (unsigned int start) const
  { return S::elements.sub_array (start); }
 
  private:
  typedef cff_stack_t<ARG, 513> S;
};
 
/* an operator prefixed by its operands in a byte string */
struct op_str_t
{
  op_code_t  op;
  byte_str_t str;
};
 
/* base of OP_SERIALIZER */
struct op_serializer_t
{
  protected:
  bool copy_opstr (hb_serialize_context_t *c, const op_str_t& opstr) const
  {
    TRACE_SERIALIZE (this);
 
    HBUINT8 *d = c->allocate_size<HBUINT8> (opstr.str.length);
    if (unlikely (!d)) return_trace (false);
    memcpy (d, &opstr.str[0], opstr.str.length);
    return_trace (true);
  }
};
 
template <typename VAL>
struct parsed_values_t
{
  void init ()
  {
    opStart = 0;
    values.init ();
  }
  void fini () { values.fini (); }
 
  void add_op (op_code_t op, const byte_str_ref_t& str_ref = byte_str_ref_t ())
  {
    VAL *val = values.push ();
    val->op = op;
    val->str = str_ref.str.sub_str (opStart, str_ref.offset - opStart);
    opStart = str_ref.offset;
  }
 
  void add_op (op_code_t op, const byte_str_ref_t& str_ref, const VAL &v)
  {
    VAL *val = values.push (v);
    val->op = op;
    val->str = str_ref.sub_str ( opStart, str_ref.offset - opStart);
    opStart = str_ref.offset;
  }
 
  bool has_op (op_code_t op) const
  {
    for (unsigned int i = 0; i < get_count (); i++)
      if (get_value (i).op == op) return true;
    return false;
  }
 
  unsigned get_count () const { return values.length; }
  const VAL &get_value (unsigned int i)   const { return values[i]; }
  const VAL &operator [] (unsigned int i) const { return get_value (i); }
 
  unsigned int       opStart;
  hb_vector_t<VAL>   values;
};
 
template <typename ARG=number_t>
struct interp_env_t
{
  void init (const byte_str_t &str_)
  {
    str_ref.reset (str_);
    argStack.init ();
    error = false;
  }
  void fini () { argStack.fini (); }
 
  bool in_error () const
  { return error || str_ref.in_error () || argStack.in_error (); }
 
  void set_error () { error = true; }
 
  op_code_t fetch_op ()
  {
    op_code_t  op = OpCode_Invalid;
    if (unlikely (!str_ref.avail ()))
      return OpCode_Invalid;
    op = (op_code_t)(unsigned char)str_ref[0];
    if (op == OpCode_escape) {
      if (unlikely (!str_ref.avail ()))
    return OpCode_Invalid;
      op = Make_OpCode_ESC(str_ref[1]);
      str_ref.inc ();
    }
    str_ref.inc ();
    return op;
  }
 
  const ARG& eval_arg (unsigned int i) { return argStack[i]; }
 
  ARG& pop_arg () { return argStack.pop (); }
  void pop_n_args (unsigned int n) { argStack.pop (n); }
 
  void clear_args () { pop_n_args (argStack.get_count ()); }
 
  byte_str_ref_t
        str_ref;
  arg_stack_t<ARG>
        argStack;
  protected:
  bool      error;
};
 
typedef interp_env_t<> num_interp_env_t;
 
template <typename ARG=number_t>
struct opset_t
{
  static void process_op (op_code_t op, interp_env_t<ARG>& env)
  {
    switch (op) {
      case OpCode_shortint:
    env.argStack.push_int ((int16_t)((env.str_ref[0] << 8) | env.str_ref[1]));
    env.str_ref.inc (2);
    break;
 
      case OpCode_TwoBytePosInt0: case OpCode_TwoBytePosInt1:
      case OpCode_TwoBytePosInt2: case OpCode_TwoBytePosInt3:
    env.argStack.push_int ((int16_t)((op - OpCode_TwoBytePosInt0) * 256 + env.str_ref[0] + 108));
    env.str_ref.inc ();
    break;
 
      case OpCode_TwoByteNegInt0: case OpCode_TwoByteNegInt1:
      case OpCode_TwoByteNegInt2: case OpCode_TwoByteNegInt3:
    env.argStack.push_int ((-(int16_t)(op - OpCode_TwoByteNegInt0) * 256 - env.str_ref[0] - 108));
    env.str_ref.inc ();
    break;
 
      default:
    /* 1-byte integer */
    if (likely ((OpCode_OneByteIntFirst <= op) && (op <= OpCode_OneByteIntLast)))
    {
      env.argStack.push_int ((int)op - 139);
    } else {
      /* invalid unknown operator */
      env.clear_args ();
      env.set_error ();
    }
    break;
    }
  }
};
 
template <typename ENV>
struct interpreter_t
{
  ~interpreter_t() { fini (); }
 
  void fini () { env.fini (); }
 
  ENV env;
};
 
} /* namespace CFF */
 
#endif /* HB_CFF_INTERP_COMMON_HH */