harfbuzz/src/hb-cff-interp-dict-common.hh
2020-04-18 16:02:55 -07:00

202 lines
4.8 KiB
C++

/*
* 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_DICT_COMMON_HH
#define HB_CFF_INTERP_DICT_COMMON_HH
#include "hb-cff-interp-common.hh"
namespace CFF {
using namespace OT;
/* an opstr and the parsed out dict value(s) */
struct dict_val_t : op_str_t
{
void init () { single_val.set_int (0); }
void fini () {}
number_t single_val;
};
typedef dict_val_t num_dict_val_t;
template <typename VAL> struct dict_values_t : parsed_values_t<VAL> {};
template <typename OPSTR=op_str_t>
struct top_dict_values_t : dict_values_t<OPSTR>
{
void init ()
{
dict_values_t<OPSTR>::init ();
charStringsOffset = 0;
FDArrayOffset = 0;
}
void fini () { dict_values_t<OPSTR>::fini (); }
unsigned int charStringsOffset;
unsigned int FDArrayOffset;
};
struct dict_opset_t : opset_t<number_t>
{
static void process_op (op_code_t op, interp_env_t<number_t>& env)
{
switch (op) {
case OpCode_longintdict: /* 5-byte integer */
env.argStack.push_longint_from_substr (env.str_ref);
break;
case OpCode_BCD: /* real number */
env.argStack.push_real (parse_bcd (env.str_ref));
break;
default:
opset_t<number_t>::process_op (op, env);
break;
}
}
/* Turns CFF's BCD format into strtod understandable string */
static double parse_bcd (byte_str_ref_t& str_ref)
{
if (unlikely (str_ref.in_error ())) return .0;
enum Nibble { DECIMAL=10, EXP_POS, EXP_NEG, RESERVED, NEG, END };
char buf[32];
unsigned char byte = 0;
for (unsigned i = 0, count = 0; count < ARRAY_LENGTH (buf); ++i, ++count)
{
unsigned nibble;
if (!(i & 1))
{
if (unlikely (!str_ref.avail ())) break;
byte = str_ref[0];
str_ref.inc ();
nibble = byte >> 4;
}
else
nibble = byte & 0x0F;
if (unlikely (nibble == RESERVED)) break;
else if (nibble == END)
{
const char *p = buf;
double pv;
if (unlikely (!hb_parse_double (&p, p + count, &pv, true/* whole buffer */)))
break;
return pv;
}
else
{
buf[count] = "0123456789.EE?-?"[nibble];
if (nibble == EXP_NEG)
{
++count;
if (unlikely (count == ARRAY_LENGTH (buf))) break;
buf[count] = '-';
}
}
}
str_ref.set_error ();
return .0;
}
static bool is_hint_op (op_code_t op)
{
switch (op)
{
case OpCode_BlueValues:
case OpCode_OtherBlues:
case OpCode_FamilyBlues:
case OpCode_FamilyOtherBlues:
case OpCode_StemSnapH:
case OpCode_StemSnapV:
case OpCode_StdHW:
case OpCode_StdVW:
case OpCode_BlueScale:
case OpCode_BlueShift:
case OpCode_BlueFuzz:
case OpCode_ForceBold:
case OpCode_LanguageGroup:
case OpCode_ExpansionFactor:
return true;
default:
return false;
}
}
};
template <typename VAL=op_str_t>
struct top_dict_opset_t : dict_opset_t
{
static void process_op (op_code_t op, interp_env_t<number_t>& env, top_dict_values_t<VAL> & dictval)
{
switch (op) {
case OpCode_CharStrings:
dictval.charStringsOffset = env.argStack.pop_uint ();
env.clear_args ();
break;
case OpCode_FDArray:
dictval.FDArrayOffset = env.argStack.pop_uint ();
env.clear_args ();
break;
case OpCode_FontMatrix:
env.clear_args ();
break;
default:
dict_opset_t::process_op (op, env);
break;
}
}
};
template <typename OPSET, typename PARAM, typename ENV=num_interp_env_t>
struct dict_interpreter_t : interpreter_t<ENV>
{
bool interpret (PARAM& param)
{
param.init ();
while (SUPER::env.str_ref.avail ())
{
OPSET::process_op (SUPER::env.fetch_op (), SUPER::env, param);
if (unlikely (SUPER::env.in_error ()))
return false;
}
return true;
}
private:
typedef interpreter_t<ENV> SUPER;
};
} /* namespace CFF */
#endif /* HB_CFF_INTERP_DICT_COMMON_HH */