src/hb-cff-interp-common-private.hh - third_party/harfbuzz - Git at Google

 /*
  * Copyright © 2018 Adobe Systems Incorporated.
  *
  *  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_PRIVATE_HH
 #define HB_CFF_INTERP_COMMON_PRIVATE_HH

 namespace CFF {

 using namespace OT;

 enum OpCode {
     /* === Dict operators === */

     /* One byte operators (0-31) */
     OpCode_version,                /* 0   CFF Top */
     OpCode_Notice,                 /* 1   CFF Top */
     OpCode_FullName,               /* 2   CFF Top */
     OpCode_FamilyName,             /* 3   CFF Top */
     OpCode_Weight,                 /* 4   CFF Top */
     OpCode_FontBBox,               /* 5   CFF Top */
     OpCode_BlueValues,             /* 6   CFF Private, CFF2 Private */
     OpCode_OtherBlues,             /* 7   CFF Private, CFF2 Private */
     OpCode_FamilyBlues,            /* 8   CFF Private, CFF2 Private */
     OpCode_FamilyOtherBlues,       /* 9   CFF Private, CFF2 Private */
     OpCode_StdHW,                  /* 10  CFF Private, CFF2 Private */
     OpCode_StdVW,                  /* 11  CFF Private, CFF2 Private */
     OpCode_escape,                 /* 12  All. Shared with CS */
     OpCode_UniqueID,               /* 13  CFF Top */
     OpCode_XUID,                   /* 14  CFF Top */
     OpCode_charset,                /* 15  CFF Top (0) */
     OpCode_Encoding,               /* 16  CFF Top (0) */
     OpCode_CharStrings,            /* 17  CFF Top, CFF2 Top */
     OpCode_Private,                /* 18  CFF Top, CFF2 FD */
     OpCode_Subrs,                  /* 19  CFF Private, CFF2 Private */
     OpCode_defaultWidthX,          /* 20  CFF Private (0) */
     OpCode_nominalWidthX,          /* 21  CFF Private (0) */
     OpCode_vsindexdict,            /* 22  CFF2 Private/CS */
     OpCode_blenddict,              /* 23  CFF2 Private/CS  */
     OpCode_vstore,                 /* 24  CFF2 Top */
     OpCode_reserved25,             /* 25 */
     OpCode_reserved26,             /* 26 */
     OpCode_reserved27,             /* 27 */

     /* Numbers */
     OpCode_shortint,               /* 28  16-bit integer, All */
     OpCode_longintdict,            /* 29  32-bit integer, All */
     OpCode_BCD,                    /* 30  real number, CFF2 Top/FD */
     OpCode_reserved31,             /* 31 */

     /* 1-byte integers */
     OpCode_OneByteIntFirst = 32,   /* All. beginning of the range of first byte ints */
     OpCode_OneByteIntLast = 246,   /* All. ending of the range of first byte int */

     /* 2-byte integers */
     OpCode_TwoBytePosInt0,         /* 247  All. first byte of two byte positive int (+108 to +1131) */
     OpCode_TwoBytePosInt1,
     OpCode_TwoBytePosInt2,
     OpCode_TwoBytePosInt3,

     OpCode_TwoByteNegInt0,         /* 251  All. first byte of two byte negative int (-1131 to -108) */
     OpCode_TwoByteNegInt1,
     OpCode_TwoByteNegInt2,
     OpCode_TwoByteNegInt3,

     /* Two byte escape operators 12, (0-41) */
     OpCode_ESC_Base = 256,
     OpCode_Copyright = OpCode_ESC_Base, /* Make_OpCode_ESC (0) CFF Top */
     OpCode_isFixedPitch,           /* Make_OpCode_ESC (1)  CFF Top (false) */
     OpCode_ItalicAngle,            /* Make_OpCode_ESC (2)  CFF Top (0) */
     OpCode_UnderlinePosition,      /* Make_OpCode_ESC (3)  CFF Top (-100) */
     OpCode_UnderlineThickness,     /* Make_OpCode_ESC (4)  CFF Top (50) */
     OpCode_PaintType,              /* Make_OpCode_ESC (5)  CFF Top (0) */
     OpCode_CharstringType,         /* Make_OpCode_ESC (6)  CFF Top (2) */
     OpCode_FontMatrix,             /* Make_OpCode_ESC (7)  CFF Top, CFF2 Top (.001 0 0 .001 0 0)*/
     OpCode_StrokeWidth,            /* Make_OpCode_ESC (8)  CFF Top (0) */
     OpCode_BlueScale,              /* Make_OpCode_ESC (9)  CFF Private, CFF2 Private (0.039625) */
     OpCode_BlueShift,              /* Make_OpCode_ESC (10) CFF Private, CFF2 Private (7) */
     OpCode_BlueFuzz,               /* Make_OpCode_ESC (11) CFF Private, CFF2 Private (1) */
     OpCode_StemSnapH,              /* Make_OpCode_ESC (12) CFF Private, CFF2 Private */
     OpCode_StemSnapV,              /* Make_OpCode_ESC (13) CFF Private, CFF2 Private */
     OpCode_ForceBold,              /* Make_OpCode_ESC (14) CFF Private (false) */
     OpCode_reservedESC15,          /* Make_OpCode_ESC (15) */
     OpCode_reservedESC16,          /* Make_OpCode_ESC (16) */
     OpCode_LanguageGroup,          /* Make_OpCode_ESC (17) CFF Private, CFF2 Private (0) */
     OpCode_ExpansionFactor,        /* Make_OpCode_ESC (18) CFF Private, CFF2 Private (0.06) */
     OpCode_initialRandomSeed,      /* Make_OpCode_ESC (19) CFF Private (0) */
     OpCode_SyntheticBase,          /* Make_OpCode_ESC (20) CFF Top */
     OpCode_PostScript,             /* Make_OpCode_ESC (21) CFF Top */
     OpCode_BaseFontName,           /* Make_OpCode_ESC (22) CFF Top */
     OpCode_BaseFontBlend,          /* Make_OpCode_ESC (23) CFF Top */
     OpCode_reservedESC24,          /* Make_OpCode_ESC (24) */
     OpCode_reservedESC25,          /* Make_OpCode_ESC (25) */
     OpCode_reservedESC26,          /* Make_OpCode_ESC (26) */
     OpCode_reservedESC27,          /* Make_OpCode_ESC (27) */
     OpCode_reservedESC28,          /* Make_OpCode_ESC (28) */
     OpCode_reservedESC29,          /* Make_OpCode_ESC (29) */
     OpCode_ROS,                    /* Make_OpCode_ESC (30) CFF Top_CID */
     OpCode_CIDFontVersion,         /* Make_OpCode_ESC (31) CFF Top_CID (0) */
     OpCode_CIDFontRevision,        /* Make_OpCode_ESC (32) CFF Top_CID (0) */
     OpCode_CIDFontType,            /* Make_OpCode_ESC (33) CFF Top_CID (0) */
     OpCode_CIDCount,               /* Make_OpCode_ESC (34) CFF Top_CID (8720) */
     OpCode_UIDBase,                /* Make_OpCode_ESC (35) CFF Top_CID */
     OpCode_FDArray,                /* Make_OpCode_ESC (36) CFF Top_CID, CFF2 Top */
     OpCode_FDSelect,               /* Make_OpCode_ESC (37) CFF Top_CID, CFF2 Top */
     OpCode_FontName,               /* Make_OpCode_ESC (38) CFF Top_CID */

     /* === CharString operators === */

     OpCode_hstem = 1,              /* 1 CFF, CFF2 */
     OpCode_Reserved2,
     OpCode_vstem,                  /* 3 CFF, CFF2 */
     OpCode_vmoveto,                /* 4 CFF, CFF2 */
     OpCode_rlineto,                /* 5 CFF, CFF2 */
     OpCode_hlineto,                /* 6 CFF, CFF2 */
     OpCode_vlineto,                /* 7 CFF, CFF2 */
     OpCode_rrcurveto,              /* 8 CFF, CFF2 */
     OpCode_Reserved9,
     OpCode_callsubr,               /* 10 CFF, CFF2 */
     OpCode_return,                 /* 11 CFF */
  // OpCode_escape,                 /* 12 CFF, CFF2 */
     OpCode_Reserved13 = 13,
     OpCode_endchar,                /* 14 CFF */
     OpCode_vsindexcs,              /* 15 CFF2 */
     OpCode_blendcs,                /* 16 CFF2 */
     OpCode_Reserved17,
     OpCode_hstemhm,                /* 18 CFF, CFF2 */
     OpCode_hintmask,               /* 19 CFF, CFF2 */
     OpCode_cntrmask,               /* 20 CFF, CFF2 */
     OpCode_rmoveto,                /* 21 CFF, CFF2 */
     OpCode_hmoveto,                /* 22 CFF, CFF2 */
     OpCode_vstemhm,                /* 23 CFF, CFF2 */
     OpCode_rcurveline,             /* 24 CFF, CFF2 */
     OpCode_rlinecurve,             /* 25 CFF, CFF2 */
     OpCode_vvcurveto,              /* 26 CFF, CFF2 */
     OpCode_hhcurveto,              /* 27 CFF, CFF2 */
  // OpCode_shortint,               /* 28 CFF, CFF2 */
     OpCode_callgsubr = 29,         /* 29 CFF, CFF2 */
     OpCode_vhcurveto,              /* 30 CFF, CFF2 */
     OpCode_hvcurveto,              /* 31 CFF, CFF2 */

     OpCode_longintcs = 255,        /* 32-bit integer */

     /* Two byte escape operators 12, (0-41) */
     OpCode_ReservedESC0 = OpCode_ESC_Base, /* Make_OpCode_ESC (0) */
     OpCode_ReservedESC1,           /* Make_OpCode_ESC (1) */
     OpCode_ReservedESC2,           /* Make_OpCode_ESC (2) */
     OpCode_and,                    /* Make_OpCode_ESC (3) CFF */
     OpCode_or,                     /* Make_OpCode_ESC (4) CFF */
     OpCode_not,                    /* Make_OpCode_ESC (5) CFF */
     OpCode_ReservedESC6,           /* Make_OpCode_ESC (6) */
     OpCode_ReservedESC7,           /* Make_OpCode_ESC (7) */
     OpCode_ReservedESC8,           /* Make_OpCode_ESC (8) */
     OpCode_abs,                    /* Make_OpCode_ESC (9) CFF */
     OpCode_add,                    /* Make_OpCode_ESC (10) CFF */
     OpCode_sub,                    /* Make_OpCode_ESC (11) CFF */
     OpCode_div,                    /* Make_OpCode_ESC (12) CFF */
     OpCode_ReservedESC13,          /* Make_OpCode_ESC (13) */
     OpCode_neg,                    /* Make_OpCode_ESC (14) CFF */
     OpCode_eq,                     /* Make_OpCode_ESC (15) CFF */
     OpCode_ReservedESC16,          /* Make_OpCode_ESC (16) */
     OpCode_ReservedESC17,          /* Make_OpCode_ESC (17) */
     OpCode_drop,                   /* Make_OpCode_ESC (18) CFF */
     OpCode_ReservedESC19,          /* Make_OpCode_ESC (19) */
     OpCode_put,                    /* Make_OpCode_ESC (20) CFF */
     OpCode_get,                    /* Make_OpCode_ESC (21) CFF */
     OpCode_ifelse,                 /* Make_OpCode_ESC (22) CFF */
     OpCode_random,                 /* Make_OpCode_ESC (23) CFF */
     OpCode_mul,                    /* Make_OpCode_ESC (24) CFF */
  // OpCode_reservedESC25,          /* Make_OpCode_ESC (25) */
     OpCode_sqrt = OpCode_mul+2,    /* Make_OpCode_ESC (26) CFF */
     OpCode_dup,                    /* Make_OpCode_ESC (27) CFF */
     OpCode_exch,                   /* Make_OpCode_ESC (28) CFF */
     OpCode_index,                  /* Make_OpCode_ESC (29) CFF */
     OpCode_roll,                   /* Make_OpCode_ESC (30) CFF */
     OpCode_reservedESC31,          /* Make_OpCode_ESC (31) */
     OpCode_reservedESC32,          /* Make_OpCode_ESC (32) */
     OpCode_reservedESC33,          /* Make_OpCode_ESC (33) */
     OpCode_hflex,                  /* Make_OpCode_ESC (34) CFF, CFF2 */
     OpCode_flex,                   /* Make_OpCode_ESC (35) CFF, CFF2 */
     OpCode_hflex1,                 /* Make_OpCode_ESC (36) CFF, CFF2 */
     OpCode_flex1                   /* Make_OpCode_ESC (37) CFF, CFF2 */
 };

 inline OpCode Make_OpCode_ESC (unsigned char byte2)  { return (OpCode)(OpCode_ESC_Base + byte2); }
 inline unsigned int OpCode_Size (OpCode op) { return (op >= OpCode_ESC_Base)? 2: 1; }

 struct Number
 {
   inline Number (void) { set_int (0); }

   inline void set_int (int v)       { is_real = false; u.int_val = v; };
   inline int to_int (void) const    { return is_real? (int)u.real_val: u.int_val; }
   inline void set_real (float v)    { is_real = true; u.real_val = v; };
   inline float to_real (void) const { return is_real? u.real_val: (float)u.int_val; }

 protected:
   bool is_real;
   union {
     int     int_val;
     float   real_val;
   } u;
 };

 /* byte string */
 struct UnsizedByteStr : UnsizedArrayOf <HBUINT8>
 {
   // encode 2-byte int (Dict/CharString) or 4-byte int (Dict)
   template <typename INTTYPE, int minVal, int maxVal>
   inline static bool serialize_int (hb_serialize_context_t *c, OpCode intOp, int value)
   {
     TRACE_SERIALIZE (this);

     if (unlikely ((value < minVal || value > maxVal)))
       return_trace (false);

     HBUINT8 *p = c->allocate_size<HBUINT8> (1);
     if (unlikely (p == nullptr)) return_trace (false);
     p->set (intOp);

     INTTYPE *ip = c->allocate_size<INTTYPE> (INTTYPE::static_size);
     if (unlikely (ip == nullptr)) return_trace (false);
     ip->set ((unsigned int)value);

     return_trace (true);
   }

   inline static bool serialize_int4 (hb_serialize_context_t *c, int value)
   { return serialize_int<HBUINT32, 0, 0x7FFFFFFF> (c, OpCode_longintdict, value); }

   inline static bool serialize_int2 (hb_serialize_context_t *c, int value)
   { return serialize_int<HBUINT16, 0, 0x7FFF> (c, OpCode_shortint, value); }
 };

 struct ByteStr
 {
   inline ByteStr (void)
     : str (&Null(UnsizedByteStr)), len (0) {}
   inline ByteStr (const UnsizedByteStr& s, unsigned int l)
     : str (&s), len (l) {}
   inline ByteStr (const char *s, unsigned int l=0)
     : str ((const UnsizedByteStr *)s), len (l) {}
   /* sub-string */
   inline ByteStr (const ByteStr &bs, unsigned int offset, unsigned int len_)
   {
     str = (const UnsizedByteStr *)&bs.str[offset];
     len = len_;
   }

   inline bool sanitize (hb_sanitize_context_t *c) const { return str->sanitize (c, len); }

   inline const HBUINT8& operator [] (unsigned int i) const {
     assert (str && (i < len));
     return (*str)[i];
   }

   inline bool serialize (hb_serialize_context_t *c, const ByteStr &src)
   {
     TRACE_SERIALIZE (this);
     HBUINT8 *dest = c->allocate_size<HBUINT8> (src.len);
     if (unlikely (dest == nullptr))
       return_trace (false);
     memcpy (dest, src.str, src.len);
     return_trace (true);
   }

   inline unsigned int get_size (void) const { return len; }

   inline bool check_limit (unsigned int offset, unsigned int count) const
   { return (offset + count <= len); }

   const UnsizedByteStr *str;
   unsigned int len;
 };

 struct SubByteStr
 {
   inline SubByteStr (void)
     : str (), offset (0) {}

   inline SubByteStr (const ByteStr &str_, unsigned int offset_ = 0)
     : str (str_), offset (offset_) {}

   inline void reset (const ByteStr &str_, unsigned int offset_ = 0)
   {
     str = str_;
     offset = offset_;
   }

   inline const HBUINT8& operator [] (unsigned int i) const {
     return str[offset + i];
   }

   inline operator ByteStr (void) const { return ByteStr (str, offset, str.len - offset); }

   inline bool avail (unsigned int count=1) const { return str.check_limit (offset, count); }
   inline void inc (unsigned int count=1) { offset += count; assert (count <= str.len); }

   ByteStr       str;
   unsigned int  offset; /* beginning of the sub-string within str */
 };

 inline float parse_bcd (SubByteStr& substr, float& v)
 {
   // XXX: TODO
   v = 0;
   for (;;) {
     if (!substr.avail ())
       return false;
     unsigned char byte = substr[0];
     substr.inc ();
     if (((byte & 0xF0) == 0xF0) || ((byte & 0x0F) == 0x0F))
       break;
   }
   return true;
 }

 /* stack */
 template <typename ELEM, int LIMIT>
 struct Stack
 {
   inline void init (void) { size = 0; }
   inline void fini (void) { }

   inline void push (const ELEM &v)
   {
     if (likely (size < kSizeLimit))
       elements[size++] = v;
   }

   inline const ELEM& pop (void)
   {
     if (likely (size > 0))
       return elements[--size];
     else
       return Null(ELEM);
   }

   inline void unpop (void)
   {
     if (likely (size < kSizeLimit))
       size++;
   }

   inline void clear (void) { size = 0; }

   inline bool check_overflow (unsigned int count=1) const { return (count <= kSizeLimit) && (count + size <= kSizeLimit); }
   inline bool check_underflow (unsigned int count=1) const { return (count <= size); }

   inline unsigned int get_size (void) const { return size; }
   inline bool is_empty (void) const { return size == 0; }

   static const unsigned int kSizeLimit = LIMIT;

   unsigned int size;
   ELEM elements[kSizeLimit];
 };

 /* argument stack */
 struct ArgStack : Stack<Number, 513>
 {
   inline void push_int (int v)
   {
     Number n;
     n.set_int (v);
     push (n);
   }

   inline void push_real (float v)
   {
     Number n;
     n.set_real (v);
     push (n);
   }

   inline bool check_pop_num (Number& n)
   {
     if (unlikely (!this->check_underflow ()))
       return false;
     n = this->pop ();
     return true;
   }

   inline bool check_pop_num2 (Number& n1, Number& n2)
   {
     if (unlikely (!this->check_underflow (2)))
       return false;
     n2 = this->pop ();
     n1 = this->pop ();
     return true;
   }

   inline bool check_pop_int (int& v)
   {
     if (unlikely (!this->check_underflow ()))
       return false;
     v = this->pop ().to_int ();
     return true;
   }

   inline bool check_pop_uint (unsigned int& v)
   {
     int  i;
     if (unlikely (!check_pop_int (i) || i < 0))
       return false;
     v = (unsigned int)i;
     return true;
   }

   inline bool check_pop_delta (hb_vector_t<Number>& vec, bool even=false)
   {
     if (even && unlikely ((this->size & 1) != 0))
       return false;

     float val = 0.0f;
     for (unsigned int i = 0; i < size; i++) {
       val += elements[i].to_real ();
       Number *n = vec.push ();
       n->set_real (val);
     }
     return true;
   }

   inline bool push_longint_from_substr (SubByteStr& substr)
   {
     if (unlikely (!substr.avail (4) || !check_overflow (1)))
       return false;
     push_int ((int32_t)*(const HBUINT32*)&substr[0]);
     substr.inc (4);
     return true;
   }

   inline void reverse_range (int i, int j)
   {
     assert (i >= 0 && i < j);
     Number  tmp;
     while (i < j)
     {
       tmp = elements[i];
       elements[i++] = elements[j];
       elements[j++] = tmp;
     }
   }
 };

 /* an operator prefixed by its operands in a byte string */
 struct OpStr
 {
   inline void init (void) {}

   OpCode  op;
   ByteStr str;
 };

 /* base of OP_SERIALIZER */
 struct OpSerializer
 {
   protected:
   inline bool copy_opstr (hb_serialize_context_t *c, const OpStr& opstr) const
   {
     TRACE_SERIALIZE (this);

     HBUINT8 *d = c->allocate_size<HBUINT8> (opstr.str.len);
     if (unlikely (d == nullptr)) return_trace (false);
     memcpy (d, &opstr.str.str[0], opstr.str.len);
     return_trace (true);
   }
 };

 struct InterpEnv
 {
   inline void init (const ByteStr &str_)
   {
     substr.reset (str_);
     argStack.init ();
   }

   inline void fini (void)
   {
     argStack.fini ();
   }

   inline bool fetch_op (OpCode &op)
   {
     if (unlikely (!substr.avail ()))
       return false;
     op = (OpCode)(unsigned char)substr[0];
     if (op == OpCode_escape) {
       if (unlikely (!substr.avail ()))
         return false;
       op = Make_OpCode_ESC (substr[1]);
       substr.inc ();
     }
     substr.inc ();
     return true;
   }

   SubByteStr    substr;
   ArgStack      argStack;
 };

 struct OpSet
 {
   static inline bool process_op (OpCode op, InterpEnv& env)
   {
     switch (op) {
       case OpCode_shortint:
         if (unlikely (!env.substr.avail (2) || !env.argStack.check_overflow (1)))
           return false;
         env.argStack.push_int ((int16_t)*(const HBUINT16*)&env.substr[0]);
         env.substr.inc (2);
         break;

       case OpCode_TwoBytePosInt0: case OpCode_TwoBytePosInt1:
       case OpCode_TwoBytePosInt2: case OpCode_TwoBytePosInt3:
         if (unlikely (!env.substr.avail () || !env.argStack.check_overflow (1)))
           return false;
         env.argStack.push_int ((int16_t)((op - OpCode_TwoBytePosInt0) * 256 + env.substr[0] + 108));
         env.substr.inc ();
         break;

       case OpCode_TwoByteNegInt0: case OpCode_TwoByteNegInt1:
       case OpCode_TwoByteNegInt2: case OpCode_TwoByteNegInt3:
         if (unlikely (!env.substr.avail () || !env.argStack.check_overflow (1)))
           return false;
         env.argStack.push_int ((int16_t)(-(op - OpCode_TwoByteNegInt0) * 256 - env.substr[0] - 108));
         env.substr.inc ();
         break;

       default:
         /* 1-byte integer */
         if (likely ((OpCode_OneByteIntFirst <= op) && (op <= OpCode_OneByteIntLast)) &&
             likely (env.argStack.check_overflow (1)))
         {
           env.argStack.push_int ((int)op - 139);
         } else {
           /* invalid unknown operator */
           env.argStack.clear ();
           return false;
         }
         break;
     }

     return true;
   }
 };

 template <typename ENV>
 struct Interpreter {

   inline ~Interpreter(void) { fini (); }

   inline void fini (void) { env.fini (); }

   ENV env;
 };

 } /* namespace CFF */

 #endif /* HB_CFF_INTERP_COMMON_PRIVATE_HH */
	/*
	* Copyright © 2018 Adobe Systems Incorporated.
	*
	* 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_PRIVATE_HH
	#define HB_CFF_INTERP_COMMON_PRIVATE_HH

	namespace CFF {

	using namespace OT;

	enum OpCode {
	/* === Dict operators === */

	/* One byte operators (0-31) */
	OpCode_version, /* 0 CFF Top */
	OpCode_Notice, /* 1 CFF Top */
	OpCode_FullName, /* 2 CFF Top */
	OpCode_FamilyName, /* 3 CFF Top */
	OpCode_Weight, /* 4 CFF Top */
	OpCode_FontBBox, /* 5 CFF Top */
	OpCode_BlueValues, /* 6 CFF Private, CFF2 Private */
	OpCode_OtherBlues, /* 7 CFF Private, CFF2 Private */
	OpCode_FamilyBlues, /* 8 CFF Private, CFF2 Private */
	OpCode_FamilyOtherBlues, /* 9 CFF Private, CFF2 Private */
	OpCode_StdHW, /* 10 CFF Private, CFF2 Private */
	OpCode_StdVW, /* 11 CFF Private, CFF2 Private */
	OpCode_escape, /* 12 All. Shared with CS */
	OpCode_UniqueID, /* 13 CFF Top */
	OpCode_XUID, /* 14 CFF Top */
	OpCode_charset, /* 15 CFF Top (0) */
	OpCode_Encoding, /* 16 CFF Top (0) */
	OpCode_CharStrings, /* 17 CFF Top, CFF2 Top */
	OpCode_Private, /* 18 CFF Top, CFF2 FD */
	OpCode_Subrs, /* 19 CFF Private, CFF2 Private */
	OpCode_defaultWidthX, /* 20 CFF Private (0) */
	OpCode_nominalWidthX, /* 21 CFF Private (0) */
	OpCode_vsindexdict, /* 22 CFF2 Private/CS */
	OpCode_blenddict, /* 23 CFF2 Private/CS */
	OpCode_vstore, /* 24 CFF2 Top */
	OpCode_reserved25, /* 25 */
	OpCode_reserved26, /* 26 */
	OpCode_reserved27, /* 27 */

	/* Numbers */
	OpCode_shortint, /* 28 16-bit integer, All */
	OpCode_longintdict, /* 29 32-bit integer, All */
	OpCode_BCD, /* 30 real number, CFF2 Top/FD */
	OpCode_reserved31, /* 31 */

	/* 1-byte integers */
	OpCode_OneByteIntFirst = 32, /* All. beginning of the range of first byte ints */
	OpCode_OneByteIntLast = 246, /* All. ending of the range of first byte int */

	/* 2-byte integers */
	OpCode_TwoBytePosInt0, /* 247 All. first byte of two byte positive int (+108 to +1131) */
	OpCode_TwoBytePosInt1,
	OpCode_TwoBytePosInt2,
	OpCode_TwoBytePosInt3,

	OpCode_TwoByteNegInt0, /* 251 All. first byte of two byte negative int (-1131 to -108) */
	OpCode_TwoByteNegInt1,
	OpCode_TwoByteNegInt2,
	OpCode_TwoByteNegInt3,

	/* Two byte escape operators 12, (0-41) */
	OpCode_ESC_Base = 256,
	OpCode_Copyright = OpCode_ESC_Base, /* Make_OpCode_ESC (0) CFF Top */
	OpCode_isFixedPitch, /* Make_OpCode_ESC (1) CFF Top (false) */
	OpCode_ItalicAngle, /* Make_OpCode_ESC (2) CFF Top (0) */
	OpCode_UnderlinePosition, /* Make_OpCode_ESC (3) CFF Top (-100) */
	OpCode_UnderlineThickness, /* Make_OpCode_ESC (4) CFF Top (50) */
	OpCode_PaintType, /* Make_OpCode_ESC (5) CFF Top (0) */
	OpCode_CharstringType, /* Make_OpCode_ESC (6) CFF Top (2) */
	OpCode_FontMatrix, /* Make_OpCode_ESC (7) CFF Top, CFF2 Top (.001 0 0 .001 0 0)*/
	OpCode_StrokeWidth, /* Make_OpCode_ESC (8) CFF Top (0) */
	OpCode_BlueScale, /* Make_OpCode_ESC (9) CFF Private, CFF2 Private (0.039625) */
	OpCode_BlueShift, /* Make_OpCode_ESC (10) CFF Private, CFF2 Private (7) */
	OpCode_BlueFuzz, /* Make_OpCode_ESC (11) CFF Private, CFF2 Private (1) */
	OpCode_StemSnapH, /* Make_OpCode_ESC (12) CFF Private, CFF2 Private */
	OpCode_StemSnapV, /* Make_OpCode_ESC (13) CFF Private, CFF2 Private */
	OpCode_ForceBold, /* Make_OpCode_ESC (14) CFF Private (false) */
	OpCode_reservedESC15, /* Make_OpCode_ESC (15) */
	OpCode_reservedESC16, /* Make_OpCode_ESC (16) */
	OpCode_LanguageGroup, /* Make_OpCode_ESC (17) CFF Private, CFF2 Private (0) */
	OpCode_ExpansionFactor, /* Make_OpCode_ESC (18) CFF Private, CFF2 Private (0.06) */
	OpCode_initialRandomSeed, /* Make_OpCode_ESC (19) CFF Private (0) */
	OpCode_SyntheticBase, /* Make_OpCode_ESC (20) CFF Top */
	OpCode_PostScript, /* Make_OpCode_ESC (21) CFF Top */
	OpCode_BaseFontName, /* Make_OpCode_ESC (22) CFF Top */
	OpCode_BaseFontBlend, /* Make_OpCode_ESC (23) CFF Top */
	OpCode_reservedESC24, /* Make_OpCode_ESC (24) */
	OpCode_reservedESC25, /* Make_OpCode_ESC (25) */
	OpCode_reservedESC26, /* Make_OpCode_ESC (26) */
	OpCode_reservedESC27, /* Make_OpCode_ESC (27) */
	OpCode_reservedESC28, /* Make_OpCode_ESC (28) */
	OpCode_reservedESC29, /* Make_OpCode_ESC (29) */
	OpCode_ROS, /* Make_OpCode_ESC (30) CFF Top_CID */
	OpCode_CIDFontVersion, /* Make_OpCode_ESC (31) CFF Top_CID (0) */
	OpCode_CIDFontRevision, /* Make_OpCode_ESC (32) CFF Top_CID (0) */
	OpCode_CIDFontType, /* Make_OpCode_ESC (33) CFF Top_CID (0) */
	OpCode_CIDCount, /* Make_OpCode_ESC (34) CFF Top_CID (8720) */
	OpCode_UIDBase, /* Make_OpCode_ESC (35) CFF Top_CID */
	OpCode_FDArray, /* Make_OpCode_ESC (36) CFF Top_CID, CFF2 Top */
	OpCode_FDSelect, /* Make_OpCode_ESC (37) CFF Top_CID, CFF2 Top */
	OpCode_FontName, /* Make_OpCode_ESC (38) CFF Top_CID */

	/* === CharString operators === */

	OpCode_hstem = 1, /* 1 CFF, CFF2 */
	OpCode_Reserved2,
	OpCode_vstem, /* 3 CFF, CFF2 */
	OpCode_vmoveto, /* 4 CFF, CFF2 */
	OpCode_rlineto, /* 5 CFF, CFF2 */
	OpCode_hlineto, /* 6 CFF, CFF2 */
	OpCode_vlineto, /* 7 CFF, CFF2 */
	OpCode_rrcurveto, /* 8 CFF, CFF2 */
	OpCode_Reserved9,
	OpCode_callsubr, /* 10 CFF, CFF2 */
	OpCode_return, /* 11 CFF */
	// OpCode_escape, /* 12 CFF, CFF2 */
	OpCode_Reserved13 = 13,
	OpCode_endchar, /* 14 CFF */
	OpCode_vsindexcs, /* 15 CFF2 */
	OpCode_blendcs, /* 16 CFF2 */
	OpCode_Reserved17,
	OpCode_hstemhm, /* 18 CFF, CFF2 */
	OpCode_hintmask, /* 19 CFF, CFF2 */
	OpCode_cntrmask, /* 20 CFF, CFF2 */
	OpCode_rmoveto, /* 21 CFF, CFF2 */
	OpCode_hmoveto, /* 22 CFF, CFF2 */
	OpCode_vstemhm, /* 23 CFF, CFF2 */
	OpCode_rcurveline, /* 24 CFF, CFF2 */
	OpCode_rlinecurve, /* 25 CFF, CFF2 */
	OpCode_vvcurveto, /* 26 CFF, CFF2 */
	OpCode_hhcurveto, /* 27 CFF, CFF2 */
	// OpCode_shortint, /* 28 CFF, CFF2 */
	OpCode_callgsubr = 29, /* 29 CFF, CFF2 */
	OpCode_vhcurveto, /* 30 CFF, CFF2 */
	OpCode_hvcurveto, /* 31 CFF, CFF2 */

	OpCode_longintcs = 255, /* 32-bit integer */

	/* Two byte escape operators 12, (0-41) */
	OpCode_ReservedESC0 = OpCode_ESC_Base, /* Make_OpCode_ESC (0) */
	OpCode_ReservedESC1, /* Make_OpCode_ESC (1) */
	OpCode_ReservedESC2, /* Make_OpCode_ESC (2) */
	OpCode_and, /* Make_OpCode_ESC (3) CFF */
	OpCode_or, /* Make_OpCode_ESC (4) CFF */
	OpCode_not, /* Make_OpCode_ESC (5) CFF */
	OpCode_ReservedESC6, /* Make_OpCode_ESC (6) */
	OpCode_ReservedESC7, /* Make_OpCode_ESC (7) */
	OpCode_ReservedESC8, /* Make_OpCode_ESC (8) */
	OpCode_abs, /* Make_OpCode_ESC (9) CFF */
	OpCode_add, /* Make_OpCode_ESC (10) CFF */
	OpCode_sub, /* Make_OpCode_ESC (11) CFF */
	OpCode_div, /* Make_OpCode_ESC (12) CFF */
	OpCode_ReservedESC13, /* Make_OpCode_ESC (13) */
	OpCode_neg, /* Make_OpCode_ESC (14) CFF */
	OpCode_eq, /* Make_OpCode_ESC (15) CFF */
	OpCode_ReservedESC16, /* Make_OpCode_ESC (16) */
	OpCode_ReservedESC17, /* Make_OpCode_ESC (17) */
	OpCode_drop, /* Make_OpCode_ESC (18) CFF */
	OpCode_ReservedESC19, /* Make_OpCode_ESC (19) */
	OpCode_put, /* Make_OpCode_ESC (20) CFF */
	OpCode_get, /* Make_OpCode_ESC (21) CFF */
	OpCode_ifelse, /* Make_OpCode_ESC (22) CFF */
	OpCode_random, /* Make_OpCode_ESC (23) CFF */
	OpCode_mul, /* Make_OpCode_ESC (24) CFF */
	// OpCode_reservedESC25, /* Make_OpCode_ESC (25) */
	OpCode_sqrt = OpCode_mul+2, /* Make_OpCode_ESC (26) CFF */
	OpCode_dup, /* Make_OpCode_ESC (27) CFF */
	OpCode_exch, /* Make_OpCode_ESC (28) CFF */
	OpCode_index, /* Make_OpCode_ESC (29) CFF */
	OpCode_roll, /* Make_OpCode_ESC (30) CFF */
	OpCode_reservedESC31, /* Make_OpCode_ESC (31) */
	OpCode_reservedESC32, /* Make_OpCode_ESC (32) */
	OpCode_reservedESC33, /* Make_OpCode_ESC (33) */
	OpCode_hflex, /* Make_OpCode_ESC (34) CFF, CFF2 */
	OpCode_flex, /* Make_OpCode_ESC (35) CFF, CFF2 */
	OpCode_hflex1, /* Make_OpCode_ESC (36) CFF, CFF2 */
	OpCode_flex1 /* Make_OpCode_ESC (37) CFF, CFF2 */
	};

	inline OpCode Make_OpCode_ESC (unsigned char byte2) { return (OpCode)(OpCode_ESC_Base + byte2); }
	inline unsigned int OpCode_Size (OpCode op) { return (op >= OpCode_ESC_Base)? 2: 1; }

	struct Number
	{
	inline Number (void) { set_int (0); }

	inline void set_int (int v) { is_real = false; u.int_val = v; };
	inline int to_int (void) const { return is_real? (int)u.real_val: u.int_val; }
	inline void set_real (float v) { is_real = true; u.real_val = v; };
	inline float to_real (void) const { return is_real? u.real_val: (float)u.int_val; }

	protected:
	bool is_real;
	union {
	int int_val;
	float real_val;
	} u;
	};

	/* byte string */
	struct UnsizedByteStr : UnsizedArrayOf <HBUINT8>
	{
	// encode 2-byte int (Dict/CharString) or 4-byte int (Dict)
	template <typename INTTYPE, int minVal, int maxVal>
	inline static bool serialize_int (hb_serialize_context_t *c, OpCode intOp, int value)
	{
	TRACE_SERIALIZE (this);

	if (unlikely ((value < minVal \|\| value > maxVal)))
	return_trace (false);

	HBUINT8 *p = c->allocate_size<HBUINT8> (1);
	if (unlikely (p == nullptr)) return_trace (false);
	p->set (intOp);

	INTTYPE *ip = c->allocate_size<INTTYPE> (INTTYPE::static_size);
	if (unlikely (ip == nullptr)) return_trace (false);
	ip->set ((unsigned int)value);

	return_trace (true);
	}

	inline static bool serialize_int4 (hb_serialize_context_t *c, int value)
	{ return serialize_int<HBUINT32, 0, 0x7FFFFFFF> (c, OpCode_longintdict, value); }

	inline static bool serialize_int2 (hb_serialize_context_t *c, int value)
	{ return serialize_int<HBUINT16, 0, 0x7FFF> (c, OpCode_shortint, value); }
	};

	struct ByteStr
	{
	inline ByteStr (void)
	: str (&Null(UnsizedByteStr)), len (0) {}
	inline ByteStr (const UnsizedByteStr& s, unsigned int l)
	: str (&s), len (l) {}
	inline ByteStr (const char *s, unsigned int l=0)
	: str ((const UnsizedByteStr *)s), len (l) {}
	/* sub-string */
	inline ByteStr (const ByteStr &bs, unsigned int offset, unsigned int len_)
	{
	str = (const UnsizedByteStr *)&bs.str[offset];
	len = len_;
	}

	inline bool sanitize (hb_sanitize_context_t *c) const { return str->sanitize (c, len); }

	inline const HBUINT8& operator [] (unsigned int i) const {
	assert (str && (i < len));
	return (*str)[i];
	}

	inline bool serialize (hb_serialize_context_t *c, const ByteStr &src)
	{
	TRACE_SERIALIZE (this);
	HBUINT8 *dest = c->allocate_size<HBUINT8> (src.len);
	if (unlikely (dest == nullptr))
	return_trace (false);
	memcpy (dest, src.str, src.len);
	return_trace (true);
	}

	inline unsigned int get_size (void) const { return len; }

	inline bool check_limit (unsigned int offset, unsigned int count) const
	{ return (offset + count <= len); }

	const UnsizedByteStr *str;
	unsigned int len;
	};

	struct SubByteStr
	{
	inline SubByteStr (void)
	: str (), offset (0) {}

	inline SubByteStr (const ByteStr &str_, unsigned int offset_ = 0)
	: str (str_), offset (offset_) {}

	inline void reset (const ByteStr &str_, unsigned int offset_ = 0)
	{
	str = str_;
	offset = offset_;
	}

	inline const HBUINT8& operator [] (unsigned int i) const {
	return str[offset + i];
	}

	inline operator ByteStr (void) const { return ByteStr (str, offset, str.len - offset); }

	inline bool avail (unsigned int count=1) const { return str.check_limit (offset, count); }
	inline void inc (unsigned int count=1) { offset += count; assert (count <= str.len); }

	ByteStr str;
	unsigned int offset; /* beginning of the sub-string within str */
	};

	inline float parse_bcd (SubByteStr& substr, float& v)
	{
	// XXX: TODO
	v = 0;
	for (;;) {
	if (!substr.avail ())
	return false;
	unsigned char byte = substr[0];
	substr.inc ();
	if (((byte & 0xF0) == 0xF0) \|\| ((byte & 0x0F) == 0x0F))
	break;
	}
	return true;
	}

	/* stack */
	template <typename ELEM, int LIMIT>
	struct Stack
	{
	inline void init (void) { size = 0; }
	inline void fini (void) { }

	inline void push (const ELEM &v)
	{
	if (likely (size < kSizeLimit))
	elements[size++] = v;
	}

	inline const ELEM& pop (void)
	{
	if (likely (size > 0))
	return elements[--size];
	else
	return Null(ELEM);
	}

	inline void unpop (void)
	{
	if (likely (size < kSizeLimit))
	size++;
	}

	inline void clear (void) { size = 0; }

	inline bool check_overflow (unsigned int count=1) const { return (count <= kSizeLimit) && (count + size <= kSizeLimit); }
	inline bool check_underflow (unsigned int count=1) const { return (count <= size); }

	inline unsigned int get_size (void) const { return size; }
	inline bool is_empty (void) const { return size == 0; }

	static const unsigned int kSizeLimit = LIMIT;

	unsigned int size;
	ELEM elements[kSizeLimit];
	};

	/* argument stack */
	struct ArgStack : Stack<Number, 513>
	{
	inline void push_int (int v)
	{
	Number n;
	n.set_int (v);
	push (n);
	}

	inline void push_real (float v)
	{
	Number n;
	n.set_real (v);
	push (n);
	}

	inline bool check_pop_num (Number& n)
	{
	if (unlikely (!this->check_underflow ()))
	return false;
	n = this->pop ();
	return true;
	}

	inline bool check_pop_num2 (Number& n1, Number& n2)
	{
	if (unlikely (!this->check_underflow (2)))
	return false;
	n2 = this->pop ();
	n1 = this->pop ();
	return true;
	}

	inline bool check_pop_int (int& v)
	{
	if (unlikely (!this->check_underflow ()))
	return false;
	v = this->pop ().to_int ();
	return true;
	}

	inline bool check_pop_uint (unsigned int& v)
	{
	int i;
	if (unlikely (!check_pop_int (i) \|\| i < 0))
	return false;
	v = (unsigned int)i;
	return true;
	}

	inline bool check_pop_delta (hb_vector_t<Number>& vec, bool even=false)
	{
	if (even && unlikely ((this->size & 1) != 0))
	return false;

	float val = 0.0f;
	for (unsigned int i = 0; i < size; i++) {
	val += elements[i].to_real ();
	Number *n = vec.push ();
	n->set_real (val);
	}
	return true;
	}

	inline bool push_longint_from_substr (SubByteStr& substr)
	{
	if (unlikely (!substr.avail (4) \|\| !check_overflow (1)))
	return false;
	push_int ((int32_t)(const HBUINT32)&substr[0]);
	substr.inc (4);
	return true;
	}

	inline void reverse_range (int i, int j)
	{
	assert (i >= 0 && i < j);
	Number tmp;
	while (i < j)
	{
	tmp = elements[i];
	elements[i++] = elements[j];
	elements[j++] = tmp;
	}
	}
	};

	/* an operator prefixed by its operands in a byte string */
	struct OpStr
	{
	inline void init (void) {}

	OpCode op;
	ByteStr str;
	};

	/* base of OP_SERIALIZER */
	struct OpSerializer
	{
	protected:
	inline bool copy_opstr (hb_serialize_context_t *c, const OpStr& opstr) const
	{
	TRACE_SERIALIZE (this);

	HBUINT8 *d = c->allocate_size<HBUINT8> (opstr.str.len);
	if (unlikely (d == nullptr)) return_trace (false);
	memcpy (d, &opstr.str.str[0], opstr.str.len);
	return_trace (true);
	}
	};

	struct InterpEnv
	{
	inline void init (const ByteStr &str_)
	{
	substr.reset (str_);
	argStack.init ();
	}

	inline void fini (void)
	{
	argStack.fini ();
	}

	inline bool fetch_op (OpCode &op)
	{
	if (unlikely (!substr.avail ()))
	return false;
	op = (OpCode)(unsigned char)substr[0];
	if (op == OpCode_escape) {
	if (unlikely (!substr.avail ()))
	return false;
	op = Make_OpCode_ESC (substr[1]);
	substr.inc ();
	}
	substr.inc ();
	return true;
	}

	SubByteStr substr;
	ArgStack argStack;
	};

	struct OpSet
	{
	static inline bool process_op (OpCode op, InterpEnv& env)
	{
	switch (op) {
	case OpCode_shortint:
	if (unlikely (!env.substr.avail (2) \|\| !env.argStack.check_overflow (1)))
	return false;
	env.argStack.push_int ((int16_t)(const HBUINT16)&env.substr[0]);
	env.substr.inc (2);
	break;

	case OpCode_TwoBytePosInt0: case OpCode_TwoBytePosInt1:
	case OpCode_TwoBytePosInt2: case OpCode_TwoBytePosInt3:
	if (unlikely (!env.substr.avail () \|\| !env.argStack.check_overflow (1)))
	return false;
	env.argStack.push_int ((int16_t)((op - OpCode_TwoBytePosInt0) * 256 + env.substr[0] + 108));
	env.substr.inc ();
	break;

	case OpCode_TwoByteNegInt0: case OpCode_TwoByteNegInt1:
	case OpCode_TwoByteNegInt2: case OpCode_TwoByteNegInt3:
	if (unlikely (!env.substr.avail () \|\| !env.argStack.check_overflow (1)))
	return false;
	env.argStack.push_int ((int16_t)(-(op - OpCode_TwoByteNegInt0) * 256 - env.substr[0] - 108));
	env.substr.inc ();
	break;

	default:
	/* 1-byte integer */
	if (likely ((OpCode_OneByteIntFirst <= op) && (op <= OpCode_OneByteIntLast)) &&
	likely (env.argStack.check_overflow (1)))
	{
	env.argStack.push_int ((int)op - 139);
	} else {
	/* invalid unknown operator */
	env.argStack.clear ();
	return false;
	}
	break;
	}

	return true;
	}
	};

	template <typename ENV>
	struct Interpreter {

	inline ~Interpreter(void) { fini (); }

	inline void fini (void) { env.fini (); }

	ENV env;
	};

	} /* namespace CFF */

	#endif /* HB_CFF_INTERP_COMMON_PRIVATE_HH */