ref: 2a98b3c431091de7434f9bde087a4f5c47f463ba
dir: /src/cff/t2parse.c/
/***************************************************************************/
/* */
/* t2parse.c */
/* */
/* OpenType parser (body). */
/* */
/* Copyright 1996-2000 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 <t2parse.h>
#include <freetype/internal/t2errors.h>
/*************************************************************************/
/* */
/* 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_t2parse
#define T2_Err_Stack_Underflow FT_Err_Invalid_Argument
#define T2_Err_Syntax_Error FT_Err_Invalid_Argument
enum
{
t2_kind_none = 0,
t2_kind_num,
t2_kind_fixed,
t2_kind_string,
t2_kind_bool,
t2_kind_delta,
t2_kind_callback,
t2_kind_max /* do not remove */
};
/* now generate handlers for the most simple fields */
typedef FT_Error (*T2_Field_Reader)( T2_Parser* parser );
typedef struct T2_Field_Handler_
{
int kind;
int code;
FT_UInt offset;
FT_Byte size;
T2_Field_Reader reader;
FT_UInt array_max;
FT_UInt count_offset;
} T2_Field_Handler;
LOCAL_FUNC
void T2_Parser_Init( T2_Parser* parser,
FT_UInt code,
void* object )
{
MEM_Set( parser, 0, sizeof ( *parser ) );
parser->top = parser->stack;
parser->object_code = code;
parser->object = object;
}
/* reads an integer */
static
FT_Long parse_t2_integer( FT_Byte* start,
FT_Byte* limit )
{
FT_Byte* p = start;
FT_Int v = *p++;
FT_Long val = 0;
if ( v == 28 )
{
if ( p + 2 > limit )
goto Bad;
val = (FT_Short)( ( (FT_Int)p[0] << 8 ) | p[1] );
p += 2;
}
else if ( v == 29 )
{
if ( p + 4 > limit )
goto Bad;
val = ( (FT_Long)p[0] << 24 ) |
( (FT_Long)p[1] << 16 ) |
( (FT_Long)p[2] << 8 ) | p[3];
p += 4;
}
else if ( v < 247 )
{
val = v - 139;
}
else if ( v < 251 )
{
if ( p + 1 > limit )
goto Bad;
val = ( v - 247 ) * 256 + p[0] + 108;
p++;
}
else
{
if ( p + 1 > limit )
goto Bad;
val = -( v - 251 ) * 256 - p[0] - 108;
p++;
}
Exit:
return val;
Bad:
val = 0;
goto Exit;
}
/* reads a real */
static
FT_Fixed parse_t2_real( FT_Byte* start,
FT_Byte* limit,
FT_Int power_ten )
{
FT_Byte* p = start;
FT_Long num, divider, result, exp;
FT_Int sign = 0, exp_sign = 0;
FT_Byte nib;
FT_Byte phase;
result = 0;
num = 0;
divider = 1;
/* first of all, read the integer part */
phase = 4;
p--;
for (;;)
{
/* read one nibble at a time */
if ( phase && ++p >= limit )
goto Bad;
nib = ( p[0] >> phase ) & 0xF;
phase = 4 - phase;
if ( nib == 0xE )
sign = 1;
else if ( nib > 9 )
break;
else
result = result * 10 + nib;
}
/* read decimal part, if any */
if ( nib == 0xa )
for (;;)
{
/* read one nibble at a time */
if ( !phase && ++p >= limit )
goto Bad;
phase = 4 - phase;
nib = ( p[0] >> phase ) & 0xF;
if ( nib >= 10 )
break;
if (divider < 10000000L)
{
num = num * 10 + nib;
divider *= 10;
}
}
/* read exponent, if any */
if ( nib == 12 )
{
exp_sign = 1;
nib = 11;
}
if ( nib == 11 )
{
exp = 0;
for (;;)
{
/* read one nibble at a time */
if ( !phase && ++p >= limit )
goto Bad;
phase = 4 - phase;
nib = ( p[0] >> phase ) & 0xF;
if ( nib >= 10 )
break;
exp = exp * 10 + nib;
}
if ( exp_sign )
exp = -exp;
power_ten += exp;
}
/* raise to power of ten if needed */
while ( power_ten > 0 )
{
result = result * 10;
num = num * 10;
power_ten--;
}
while ( power_ten < 0 )
{
result = result / 10;
divider = divider * 10;
power_ten++;
}
if ( num )
result += FT_DivFix( num, divider );
if ( sign )
result = -result;
Exit:
return result;
Bad:
result = 0;
goto Exit;
}
/* reads a number, either integer or real */
static
FT_Long t2_parse_num( FT_Byte** d )
{
return ( **d == 30 ? ( parse_t2_real( d[0], d[1], 0 ) >> 16 )
: parse_t2_integer( d[0], d[1] ) );
}
/* reads a floating point number, either integer or real */
static
FT_Fixed t2_parse_fixed( FT_Byte** d )
{
return ( **d == 30 ? parse_t2_real( d[0], d[1], 0 )
: parse_t2_integer( d[0], d[1] ) << 16 );
}
static
FT_Error parse_font_matrix( T2_Parser* parser )
{
CFF_Top_Dict* dict = (CFF_Top_Dict*)parser->object;
FT_Matrix* matrix = &dict->font_matrix;
FT_Byte** data = parser->stack;
FT_Error error;
error = T2_Err_Stack_Underflow;
if ( parser->top >= parser->stack + 4 )
{
matrix->xx = t2_parse_fixed( data++ );
matrix->yx = t2_parse_fixed( data++ );
matrix->xy = t2_parse_fixed( data++ );
matrix->yy = t2_parse_fixed( data );
error = 0;
}
return error;
}
static
FT_Error parse_font_bbox( T2_Parser* parser )
{
CFF_Top_Dict* dict = (CFF_Top_Dict*)parser->object;
FT_BBox* bbox = &dict->font_bbox;
FT_Byte** data = parser->stack;
FT_Error error;
error = T2_Err_Stack_Underflow;
if ( parser->top >= parser->stack + 4 )
{
bbox->xMin = t2_parse_num( data++ );
bbox->yMin = t2_parse_num( data++ );
bbox->xMax = t2_parse_num( data++ );
bbox->yMax = t2_parse_num( data );
error = 0;
}
return error;
}
static
FT_Error parse_private_dict( T2_Parser* parser )
{
CFF_Top_Dict* dict = (CFF_Top_Dict*)parser->object;
FT_Byte** data = parser->stack;
FT_Error error;
error = T2_Err_Stack_Underflow;
if ( parser->top >= parser->stack + 2 )
{
dict->private_size = t2_parse_num( data++ );
dict->private_offset = t2_parse_num( data );
error = 0;
}
return error;
}
static
FT_Error parse_cid_ros( T2_Parser* parser )
{
CFF_Top_Dict* dict = (CFF_Top_Dict*)parser->object;
FT_Byte** data = parser->stack;
FT_Error error;
error = T2_Err_Stack_Underflow;
if ( parser->top >= parser->stack + 3 )
{
dict->cid_registry = (FT_UInt)t2_parse_num( data++ );
dict->cid_ordering = (FT_UInt)t2_parse_num( data++ );
dict->cid_supplement = (FT_ULong)t2_parse_num( data );
error = 0;
}
return error;
}
#define T2_FIELD_NUM( code, name ) \
T2_FIELD( code, name, t2_kind_num )
#define T2_FIELD_FIXED( code, name ) \
T2_FIELD( code, name, t2_kind_fixed )
#define T2_FIELD_STRING( code, name ) \
T2_FIELD( code, name, t2_kind_string )
#define T2_FIELD_BOOL( code, name ) \
T2_FIELD( code, name, t2_kind_bool )
#define T2_FIELD_DELTA( code, name,max ) \
T2_FIELD( code, name, t2_kind_delta )
#define T2_REF( s, f ) ( ((s*)0)->f )
#define T2_FIELD_CALLBACK( code, name ) \
{ \
t2_kind_callback, \
code | T2CODE, \
0, 0, \
parse_ ## name, \
0, 0 },
#undef T2_FIELD
#define T2_FIELD( code, name, kind ) \
{ \
kind, \
code | T2CODE, \
(FT_UInt)(char*)&T2_REF( T2TYPE, name ), \
sizeof( T2_REF( T2TYPE, name ) ), \
0 \
},
#undef T2_FIELD_DELTA
#define T2_FIELD_DELTA( code, name, max ) \
{ \
t2_kind_delta, \
code | T2CODE, \
(FT_UInt)(char*)&T2_REF( T2TYPE, name ), \
sizeof( T2_REF( T2TYPE, name ) ), \
0, \
max, \
(FT_UInt)(char*)&T2_REF( T2TYPE, num_ ## name ) \
},
#define T2CODE_TOPDICT 0x1000
#define T2CODE_PRIVATE 0x2000
static const T2_Field_Handler t2_field_handlers[] =
{
#include <t2tokens.h>
{ 0, 0, 0, 0, 0, 0, 0 }
};
LOCAL_FUNC
FT_Error T2_Parser_Run( T2_Parser* parser,
FT_Byte* start,
FT_Byte* limit )
{
FT_Byte* p = start;
FT_Error error = 0;
parser->top = parser->stack;
parser->start = start;
parser->limit = limit;
parser->cursor = start;
while ( p < limit )
{
FT_Byte v = *p;
if ( v >= 27 && v != 31 )
{
/* it's a number; we will push its position on the stack */
if ( parser->top - parser->stack >= T2_MAX_STACK_DEPTH )
goto Stack_Overflow;
*parser->top ++ = p;
/* now, skip it */
if ( v == 30 )
{
/* skip real number */
for (;;)
{
if ( p >= limit )
goto Syntax_Error;
v = p[0] >> 4;
if ( v == 15 )
break;
v = p[0] & 0xF;
if ( v == 15 )
break;
p++;
}
p++;
}
else if ( v == 28 )
p += 2;
else if ( v == 29 )
p += 4;
else if ( v > 246 )
p += 1;
}
else
{
/* this is not a number, hence it's an operator. Compute its code */
/* and look for it in our current list. */
FT_UInt code;
FT_Int num_args = parser->top - parser->stack;
const T2_Field_Handler* field;
/* first of all, a trivial check */
if ( num_args < 1 )
goto Stack_Underflow;
*parser->top = p;
code = v;
if ( v == 12 )
{
/* two byte operator */
p++;
code = 0x100 | p[0];
}
code = code | parser->object_code;
for ( field = t2_field_handlers; field->kind; field++ )
{
if ( field->code == code )
{
/* we found our field's handler; read it */
FT_Long val;
FT_Byte* q = (FT_Byte*)parser->object + field->offset;
switch ( field->kind )
{
case t2_kind_bool:
case t2_kind_string:
case t2_kind_num:
val = t2_parse_num( parser->stack );
goto Store_Number;
case t2_kind_fixed:
val = t2_parse_fixed( parser->stack );
Store_Number:
switch ( field->size )
{
case 1:
*(FT_Byte*)q = (FT_Byte)val;
break;
case 2:
*(FT_Short*)q = (FT_Short)val;
break;
default:
*(FT_Long*)q = val;
}
break;
case t2_kind_delta:
{
FT_Byte* qcount = (FT_Byte*)parser->object +
field->count_offset;
FT_Long val;
FT_Byte** data = parser->stack;
if ( num_args > field->array_max )
num_args = field->array_max;
/* store count */
*qcount = (FT_Byte)num_args;
val = 0;
while ( num_args > 0 )
{
val += t2_parse_num( data++ );
switch ( field->size )
{
case 1:
*(FT_Byte*)q = (FT_Byte)val;
break;
case 2:
*(FT_Short*)q = (FT_Short)val;
break;
default:
*(FT_Long*)q = val;
}
q += field->size;
num_args--;
}
}
break;
default: /* callback */
error = field->reader( parser );
if ( error )
goto Exit;
}
goto Found;
}
}
/* this is an unknown operator, or it is unsupported; */
/* we will ignore it for now. */
Found:
/* clear stack */
parser->top = parser->stack;
}
p++;
}
Exit:
return error;
Stack_Overflow:
error = T2_Err_Invalid_Argument;
goto Exit;
Stack_Underflow:
error = T2_Err_Invalid_Argument;
goto Exit;
Syntax_Error:
error = T2_Err_Invalid_Argument;
goto Exit;
}
/* END */