/***************************************************************************/
/* */
/* t1decode.c */
/* */
/* PostScript Type 1 decoding routines (body). */
/* */
/* Copyright 2000-2018 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */
/* modified, and distributed under the terms of the FreeType project */
/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
/* this file you indicate that you have read the license and */
/* understand and accept it fully. */
/* */
/***************************************************************************/
#include "ft2build.h"
#include FT_INTERNAL_CALC_H
#include FT_INTERNAL_DEBUG_H
#include FT_INTERNAL_POSTSCRIPT_HINTS_H
#include FT_INTERNAL_HASH_H
#include FT_OUTLINE_H
#include "t1decode.h"
#include "psobjs.h"
#include "psauxerr.h"
/* ensure proper sign extension */
#define Fix2Int( f ) ( (FT_Int)(FT_Short)( (f) >> 16 ) )
/*************************************************************************/
/* */
/* The macro FT_COMPONENT is used in trace mode. It is an implicit */
/* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
/* messages during execution. */
/* */
#undef FT_COMPONENT
#define FT_COMPONENT trace_t1decode
typedef enum T1_Operator_
{
op_none = 0,
op_endchar,
op_hsbw,
op_seac,
op_sbw,
op_closepath,
op_hlineto,
op_hmoveto,
op_hvcurveto,
op_rlineto,
op_rmoveto,
op_rrcurveto,
op_vhcurveto,
op_vlineto,
op_vmoveto,
op_dotsection,
op_hstem,
op_hstem3,
op_vstem,
op_vstem3,
op_div,
op_callothersubr,
op_callsubr,
op_pop,
op_return,
op_setcurrentpoint,
op_unknown15,
op_max /* never remove this one */
} T1_Operator;
static
const FT_Int t1_args_count[op_max] =
{
0, /* none */
0, /* endchar */
2, /* hsbw */
5, /* seac */
4, /* sbw */
0, /* closepath */
1, /* hlineto */
1, /* hmoveto */
4, /* hvcurveto */
2, /* rlineto */
2, /* rmoveto */
6, /* rrcurveto */
4, /* vhcurveto */
1, /* vlineto */
1, /* vmoveto */
0, /* dotsection */
2, /* hstem */
6, /* hstem3 */
2, /* vstem */
6, /* vstem3 */
2, /* div */
-1, /* callothersubr */
1, /* callsubr */
0, /* pop */
0, /* return */
2, /* setcurrentpoint */
2 /* opcode 15 (undocumented and obsolete) */
};
/*************************************************************************/
/* */
/* <Function> */
/* t1_lookup_glyph_by_stdcharcode_ps */
/* */
/* <Description> */
/* Looks up a given glyph by its StandardEncoding charcode. Used to */
/* implement the SEAC Type 1 operator in the Adobe engine */
/* */
/* <Input> */
/* face :: The current face object. */
/* */
/* charcode :: The character code to look for. */
/* */
/* <Return> */
/* A glyph index in the font face. Returns -1 if the corresponding */
/* glyph wasn't found. */
/* */
FT_LOCAL_DEF( FT_Int )
t1_lookup_glyph_by_stdcharcode_ps( PS_Decoder* decoder,
FT_Int charcode )
{
FT_UInt n;
const FT_String* glyph_name;
FT_Service_PsCMaps psnames = decoder->psnames;
/* check range of standard char code */
if ( charcode < 0 || charcode > 255 )
return -1;
glyph_name = psnames->adobe_std_strings(
psnames->adobe_std_encoding[charcode]);
for ( n = 0; n < decoder->num_glyphs; n++ )
{
FT_String* name = (FT_String*)decoder->glyph_names[n];
if ( name &&
name[0] == glyph_name[0] &&
ft_strcmp( name, glyph_name ) == 0 )
return (FT_Int)n;
}
return -1;
}
/*************************************************************************/
/* */
/* <Function> */
/* t1_decoder_parse_metrics */
/* */
/* <Description> */
/* Parses a given Type 1 charstrings program to extract width */
/* */
/* <Input> */
/* decoder :: The current Type 1 decoder. */
/* */
/* charstring_base :: The base address of the charstring stream. */
/* */
/* charstring_len :: The length in bytes of the charstring stream. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
FT_LOCAL_DEF( FT_Error )
t1_decoder_parse_metrics( T1_Decoder decoder,
FT_Byte* charstring_base,
FT_UInt charstring_len )
{
T1_Decoder_Zone zone;
FT_Byte* ip;
FT_Byte* limit;
T1_Builder builder = &decoder->builder;
/* First of all, initialize the decoder */
decoder->top = decoder->stack;
decoder->zone = decoder->zones;
zone = decoder->zones;
builder->parse_state = T1_Parse_Start;
FT_TRACE4(( "\n"
"Start charstring: get width\n" ));
zone->base = charstring_base;
limit = zone->limit = charstring_base + charstring_len;
ip = zone->cursor = zone->base;
/* now, execute loop */
while ( ip < limit )
{
FT_Long* top = decoder->top;
T1_Operator op = op_none;
FT_Int32 value = 0;
/*********************************************************************/
/* */
/* Decode operator or operand */
/* */
/* */
/* first of all, decompress operator or value */
switch ( *ip++ )
{
case 1:
case 3:
case 4:
case 5:
case 6:
case 7:
case 8:
case 9:
case 10:
case 11:
case 14:
case 15:
case 21:
case 22:
case 30:
case 31:
goto No_Width;
case 13:
op = op_hsbw;
break;
case 12:
if ( ip >= limit )
{
FT_ERROR(( "t1_decoder_parse_metrics:"
" invalid escape (12+EOF)\n" ));
goto Syntax_Error;
}
switch ( *ip++ )
{
case 7:
op = op_sbw;
break;
default:
goto No_Width;
}
break;
case 255: /* four bytes integer */
if ( ip + 4 > limit )
{
FT_ERROR(( "t1_decoder_parse_metrics:"
" unexpected EOF in integer\n" ));
goto Syntax_Error;
}
value = (FT_Int32)( ( (FT_UInt32)ip[0] << 24 ) |
( (FT_UInt32)ip[1] << 16 ) |
( (FT_UInt32)ip[2] << 8 ) |
(FT_UInt32)ip[3] );
ip += 4;
/* According to the specification, values > 32000 or < -32000 must */
/* be followed by a `div' operator to make the result be in the */
/* range [-32000;32000]. We expect that the second argument of */
/* `div' is not a large number. Additionally, we don't handle */
/* stuff like `<large1> <large2> <num> div <num> div' or */
/* <large1> <large2> <num> div div'. This is probably not allowed */
/* anyway. */
if ( value > 32000 || value < -32000 )
{
FT_ERROR(( "t1_decoder_parse_metrics:"
" large integer found for width\n" ));
goto Syntax_Error;
}
else
{
value = (FT_Int32)( (FT_UInt32)value << 16 );
}
break;
default:
if ( ip[-1] >= 32 )
{
if ( ip[-1] < 247 )
value = (FT_Int32)ip[-1] - 139;
else
{
if ( ++ip > limit )
{
FT_ERROR(( "t1_decoder_parse_metrics:"
" unexpected EOF in integer\n" ));
goto Syntax_Error;
}
if ( ip[-2] < 251 )
value = ( ( ip[-2] - 247 ) * 256 ) + ip[-1] + 108;
else
value = -( ( ( ip[-2] - 251 ) * 256 ) + ip[-1] + 108 );
}
value = (FT_Int32)( (FT_UInt32)value << 16 );
}
else
{
FT_ERROR(( "t1_decoder_parse_metrics:"
" invalid byte (%d)\n", ip[-1] ));
goto Syntax_Error;
}
}
/*********************************************************************/
/* */
/* Push value on stack, or process operator */
/* */
/* */
if ( op == op_none )
{
if ( top - decoder->stack >= T1_MAX_CHARSTRINGS_OPERANDS )
{
FT_ERROR(( "t1_decoder_parse_metrics: stack overflow\n" ));
goto Syntax_Error;
}
*top++ = value;
decoder->top = top;
}
else /* general operator */
{
FT_Int num_args = t1_args_count[op];
FT_ASSERT( num_args >= 0 );
if ( top - decoder->stack < num_args )
goto Stack_Underflow;
top -= num_args;
switch ( op )
{
case op_hsbw:
FT_TRACE4(( " hsbw" ));
builder->parse_state = T1_Parse_Have_Width;
builder->left_bearing.x = ADD_LONG( builder->left_bearing.x,
top[0] );
builder->advance.x = top[1];
builder->advance.y = 0;
/* we only want to compute the glyph's metrics */
/* (lsb + advance width), not load the rest of */
/* it; so exit immediately */
return FT_Err_Ok;
case op_sbw:
FT_TRACE4(( " sbw" ));
builder->parse_state = T1_Parse_Have_Width;
builder->left_bearing.x = ADD_LONG( builder->left_bearing.x,
top[0] );
builder->left_bearing.y = ADD_LONG( builder->left_bearing.y,
top[1] );
builder->advance.x = top[2];
builder->advance.y = top[3];
/* we only want to compute the glyph's metrics */
/* (lsb + advance width), not load the rest of */
/* it; so exit immediately */
return FT_Err_Ok;
default:
FT_ERROR(( "t1_decoder_parse_metrics:"
" unhandled opcode %d\n", op ));
goto Syntax_Error;
}
} /* general operator processing */
} /* while ip < limit */
FT_TRACE4(( "..end..\n\n" ));
No_Width:
FT_ERROR(( "t1_decoder_parse_metrics:"
" no width, found op %d instead\n",
ip[-1] ));
Syntax_Error:
return FT_THROW( Syntax_Error );
Stack_Underflow:
return FT_THROW( Stack_Underflow );
}
/* initialize T1 decoder */
FT_LOCAL_DEF( FT_Error )
t1_decoder_init( T1_Decoder decoder,
FT_Face face,
FT_Size size,
FT_GlyphSlot slot,
FT_Byte** glyph_names,
PS_Blend blend,
FT_Bool hinting,
FT_Render_Mode hint_mode,
T1_Decoder_Callback parse_callback )
{
FT_ZERO( decoder );
/* retrieve PSNames interface from list of current modules */
{
FT_Service_PsCMaps psnames;
FT_FACE_FIND_GLOBAL_SERVICE( face, psnames, POSTSCRIPT_CMAPS );
if ( !psnames )
{
FT_ERROR(( "t1_decoder_init:"
" the `psnames' module is not available\n" ));
return FT_THROW( Unimplemented_Feature );
}
decoder->psnames = psnames;
}
t1_builder_init( &decoder->builder, face, size, slot, hinting );
/* decoder->buildchar and decoder->len_buildchar have to be */
/* initialized by the caller since we cannot know the length */
/* of the BuildCharArray */
decoder->num_glyphs = (FT_UInt)face->num_glyphs;
decoder->glyph_names = glyph_names;
decoder->hint_mode = hint_mode;
decoder->blend = blend;
decoder->parse_callback = parse_callback;
decoder->funcs = t1_decoder_funcs;
return FT_Err_Ok;
}
/* finalize T1 decoder */
FT_LOCAL_DEF( void )
t1_decoder_done( T1_Decoder decoder )
{
FT_Memory memory = decoder->builder.memory;
t1_builder_done( &decoder->builder );
if ( decoder->cf2_instance.finalizer )
{
decoder->cf2_instance.finalizer( decoder->cf2_instance.data );
FT_FREE( decoder->cf2_instance.data );
}
}
/* END */