ref: f2438e1da975672c22e8794030e3c4450f7a3525
dir: /src/otlayout/otlgsub.c/
/***************************************************************************/
/* */
/* otlgsub.c */
/* */
/* OpenType layout support, GSUB table (body). */
/* */
/* Copyright 2002, 2004 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 "otlgsub.h"
#include "otlcommn.h"
#include "otlparse.h"
/* forward declaration */
static OTL_ValidateFunc otl_gsub_validate_funcs[];
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** GSUB LOOKUP TYPE 1 *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/*
* 1: Single Substitution - Table format(s)
*
* This table is used to substitute individual glyph indices
* with another one. There are only two sub-formats:
*
* Name Offset Size Description
* --------------------------------------------------------------
* format 0 2 sub-table format (1)
* offset 2 2 offset to coverage table
* delta 4 2 16-bit delta to apply on all
* covered glyph indices
*
* Name Offset Size Description
* --------------------------------------------------------------
* format 0 2 sub-table format (2)
* offset 2 2 offset to coverage table
* count 4 2 coverage table count
* substs[] 6 2*count substituted glyph indices,
*
*/
static void
otl_gsub_lookup1_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt format;
OTL_UNUSED( lookup_count );
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
switch ( format )
{
case 1:
{
OTL_Bytes coverage;
OTL_Int delta;
OTL_Long idx;
OTL_CHECK( 4 );
coverage = table + OTL_NEXT_USHORT( p );
delta = OTL_NEXT_SHORT( p );
otl_coverage_validate( coverage, valid );
idx = otl_coverage_get_first( coverage ) + delta;
if ( idx < 0 )
OTL_INVALID_DATA;
idx = otl_coverage_get_last( coverage ) + delta;
if ( (OTL_UInt)idx >= glyph_count )
OTL_INVALID_DATA;
}
break;
case 2:
{
OTL_UInt coverage, num_glyphs;
OTL_CHECK( 4 );
coverage = OTL_NEXT_USHORT( p );
num_glyphs = OTL_NEXT_USHORT( p );
otl_coverage_validate( table + coverage, valid );
OTL_CHECK( num_glyphs * 2 );
for ( ; num_glyphs > 0; num_glyphs-- )
if ( OTL_NEXT_USHORT( p ) >= glyph_count )
OTL_INVALID_DATA;
}
break;
default:
OTL_INVALID_DATA;
}
}
#if 0
static OTL_Bool
otl_gsub_lookup1_apply( OTL_Bytes table,
OTL_Parser parser )
{
OTL_Bytes p = table;
OTL_Bytes coverage;
OTL_UInt format, gindex, property;
OTL_Long index;
OTL_Bool subst = 0;
if ( parser->context_len != 0xFFFFU && parser->context_len < 1 )
goto Exit;
gindex = otl_parser_get_gindex( parser );
otl_parser_check_property( parser, gindex, &property );
if ( parser->error )
goto Exit;
format = OTL_NEXT_USHORT(p);
coverage = table + OTL_NEXT_USHORT(p);
index = otl_coverage_get_index( coverage, gindex );
if ( index >= 0 )
{
switch ( format )
{
case 1:
{
OTL_Int delta = OTL_NEXT_SHORT( p );
gindex = ( gindex + delta ) & 0xFFFFU;
otl_parser_replace_1( parser, gindex );
subst = 1;
}
break;
case 2:
{
OTL_UInt count = OTL_NEXT_USHORT( p );
if ( (OTL_UInt)index < count )
{
p += index * 2;
otl_parser_replace_1( parser, OTL_PEEK_USHORT( p ) );
subst = 1;
}
}
break;
default:
;
}
}
Exit:
return subst;
}
#endif
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** GSUB LOOKUP TYPE 2 *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/*
* 2: Multiple Substitution - Table format(s)
*
* Replaces a single glyph with one or more glyphs.
*
* Name Offset Size Description
* --------------------------------------------------------------
* format 0 2 sub-table format (1)
* offset 2 2 offset to coverage table
* count 4 2 coverage table count
* sequencess[] 6 2*count offsets to sequence items
*
* each sequence item has the following format:
*
* Name Offset Size Description
* --------------------------------------------------------------
* count 0 2 number of replacement glyphs
* gindices[] 2 2*count string of glyph indices
*
*/
static void
otl_sequence_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt num_glyphs;
OTL_CHECK( 2 );
num_glyphs = OTL_NEXT_USHORT( p );
/* according to the specification, `num_glyphs' should be > 0; */
/* we can deal with these cases pretty well, however */
OTL_CHECK( num_glyphs * 2 );
for ( ; num_glyphs > 0; num_glyphs-- )
if ( OTL_NEXT_USHORT( p ) >= glyph_count )
OTL_INVALID_DATA;
}
static void
otl_gsub_lookup2_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt format;
OTL_UNUSED( lookup_count );
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
switch ( format )
{
case 1:
{
OTL_UInt coverage, num_sequences;
OTL_CHECK( 4 );
coverage = OTL_NEXT_USHORT( p );
num_sequences = OTL_NEXT_USHORT( p );
otl_coverage_validate( table + coverage, valid );
OTL_CHECK( num_sequences * 2 );
/* scan sequence records */
for ( ; num_sequences > 0; num_sequences-- )
otl_sequence_validate( table + OTL_NEXT_USHORT( p ), glyph_count,
valid );
}
break;
default:
OTL_INVALID_DATA;
}
}
#if 0
static OTL_Bool
otl_gsub_lookup2_apply( OTL_Bytes table,
OTL_Parser parser )
{
OTL_Bytes p = table;
OTL_Bytes coverage, sequence;
OTL_UInt format, gindex, property, context_len, seq_count, count;
OTL_Long index;
OTL_Bool subst = 0;
if ( parser->context_len != 0xFFFFU && parser->context_len < 1 )
goto Exit;
gindex = otl_parser_get_gindex( parser );
otl_parser_check_property( parser, gindex, &property );
if ( parser->error )
goto Exit;
p += 2; /* skip format */
coverage = table + OTL_NEXT_USHORT( p );
seq_count = OTL_NEXT_USHORT( p );
index = otl_coverage_get_index( coverage, gindex );
if ( (OTL_UInt)index >= seq_count || index < 0 )
goto Exit;
p += index * 2;
sequence = table + OTL_PEEK_USHORT( p );
p = sequence;
count = OTL_NEXT_USHORT( p );
otl_parser_replace_n( parser, count, p );
subst = 1;
Exit:
return subst;
}
#endif
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** GSUB LOOKUP TYPE 3 *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/*
* 3: Alternate Substitution - Table format(s)
*
* Replaces a single glyph by another one taken liberally
* in a list of alternatives.
*
* Name Offset Size Description
* ---------------------------------------------------------------
* format 0 2 sub-table format (1)
* offset 2 2 offset to coverage table
* count 4 2 coverage table count
* alternates[] 6 2*count offsets to alternate items
*
* each alternate item has the following format:
*
* Name Offset Size Description
* ---------------------------------------------------------------
* count 0 2 number of replacement glyphs
* gindices[] 2 2*count string of glyph indices, each
* one is a valid alternative
*
*/
static void
otl_alternate_set_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt num_glyphs;
OTL_CHECK( 2 );
num_glyphs = OTL_NEXT_USHORT( p );
OTL_CHECK( num_glyphs * 2 );
for ( ; num_glyphs > 0; num_glyphs-- )
if ( OTL_NEXT_USHORT( p ) >= glyph_count )
OTL_INVALID_DATA;
}
static void
otl_gsub_lookup3_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt format;
OTL_UNUSED( lookup_count );
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
switch ( format )
{
case 1:
{
OTL_UInt coverage, num_alternate_sets;
OTL_CHECK( 4 );
coverage = OTL_NEXT_USHORT( p );
num_alternate_sets = OTL_NEXT_USHORT( p );
otl_coverage_validate( table + coverage, valid );
OTL_CHECK( num_alternate_sets * 2 );
/* scan alternate set records */
for ( ; num_alternate_sets > 0; num_alternate_sets-- )
otl_alternate_set_validate( table + OTL_NEXT_USHORT( p ),
glyph_count, valid );
}
break;
default:
OTL_INVALID_DATA;
}
}
#if 0
static OTL_Bool
otl_gsub_lookup3_apply( OTL_Bytes table,
OTL_Parser parser )
{
OTL_Bytes p = table;
OTL_Bytes coverage, alternates;
OTL_UInt format, gindex, property, seq_count, count;
OTL_Long index;
OTL_Bool subst = 0;
OTL_GSUB_Alternate alternate = parser->alternate;
if ( parser->context_len != 0xFFFFU && parser->context_len < 1 )
goto Exit;
if ( alternate == 0 )
goto Exit;
gindex = otl_parser_get_gindex( parser );
otl_parser_check_property( parser, gindex, &property );
if ( parser->error )
goto Exit;
p += 2; /* skip format */
coverage = table + OTL_NEXT_USHORT( p );
seq_count = OTL_NEXT_USHORT( p );
index = otl_coverage_get_index( coverage, gindex );
if ( (OTL_UInt)index >= seq_count || index < 0 )
goto Exit;
p += index * 2;
alternates = table + OTL_PEEK_USHORT( p );
p = alternates;
count = OTL_NEXT_USHORT( p );
gindex = alternate->handler_func(
gindex, count, p, alternate->handler_data );
otl_parser_replace_1( parser, gindex );
subst = 1;
Exit:
return subst;
}
#endif
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** GSUB LOOKUP TYPE 4 *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
static void
otl_ligature_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt glyph_id, num_components;
OTL_CHECK( 4 );
glyph_id = OTL_NEXT_USHORT( p );
if ( glyph_id >= glyph_count )
OTL_INVALID_DATA;
num_components = OTL_NEXT_USHORT( p );
if ( num_components == 0 )
OTL_INVALID_DATA;
num_components--;
OTL_CHECK( num_components * 2 );
}
static void
otl_ligature_set_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt num_ligatures;
OTL_CHECK( 2 );
num_ligatures = OTL_NEXT_USHORT( p );
OTL_CHECK( num_ligatures * 2 );
/* scan ligature records */
for ( ; num_ligatures > 0; num_ligatures-- )
otl_ligature_validate( table + OTL_NEXT_USHORT( p ), glyph_count,
valid );
}
static void
otl_gsub_lookup4_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt format;
OTL_UNUSED( lookup_count);
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
switch ( format )
{
case 1:
{
OTL_UInt coverage, num_ligsets;
OTL_CHECK( 4 );
coverage = OTL_NEXT_USHORT( p );
num_ligsets = OTL_NEXT_USHORT( p );
otl_coverage_validate( table + coverage, valid );
OTL_CHECK( num_ligsets * 2 );
/* scan ligature set records */
for ( ; num_ligsets > 0; num_ligsets-- )
otl_ligature_set_validate( table + OTL_NEXT_USHORT( p ),
glyph_count, valid );
}
break;
default:
OTL_INVALID_DATA;
}
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** GSUB LOOKUP TYPE 5 *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/* used for both format 1 and 2 */
static void
otl_sub_rule_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt num_glyphs, num_subst;
OTL_CHECK( 4 );
num_glyphs = OTL_NEXT_USHORT( p );
num_subst = OTL_NEXT_USHORT( p );
if ( num_glyphs == 0 )
OTL_INVALID_DATA;
OTL_CHECK( ( num_glyphs - 1 ) * 2 + num_subst * 4 );
for ( ; num_subst > 0; num_subst-- )
{
if ( OTL_NEXT_USHORT( p ) >= num_glyphs )
OTL_INVALID_DATA;
if ( OTL_NEXT_USHORT( p ) >= lookup_count )
OTL_INVALID_DATA;
}
/* no need to check glyph indices/classes used as input for this */
/* context rule since even invalid glyph indices/classes return a */
/* meaningful result */
}
/* used for both format 1 and 2 */
static void
otl_sub_rule_set_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt num_subrules;
OTL_CHECK( 2 );
num_subrules = OTL_NEXT_USHORT( p );
OTL_CHECK( num_subrules * 2 );
/* scan subrule records */
for ( ; num_subrules > 0; num_subrules-- )
otl_sub_rule_validate( table + OTL_NEXT_USHORT( p ), lookup_count,
valid );
}
static void
otl_gsub_lookup5_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt format;
OTL_UNUSED( glyph_count );
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
switch ( format )
{
case 1:
{
OTL_UInt coverage, num_subrulesets;
OTL_CHECK( 4 );
coverage = OTL_NEXT_USHORT( p );
num_subrulesets = OTL_NEXT_USHORT( p );
otl_coverage_validate( table + coverage, valid );
OTL_CHECK( num_subrulesets * 2 );
/* scan subrule set records */
for ( ; num_subrulesets > 0; num_subrulesets-- )
otl_sub_rule_set_validate( table + OTL_NEXT_USHORT( p ),
lookup_count, valid );
}
break;
case 2:
{
OTL_UInt coverage, class_def, num_subclass_sets;
OTL_CHECK( 6 );
coverage = OTL_NEXT_USHORT( p );
class_def = OTL_NEXT_USHORT( p );
num_subclass_sets = OTL_NEXT_USHORT( p );
otl_coverage_validate( table + coverage, valid );
otl_class_definition_validate( table + class_def, valid );
OTL_CHECK( num_subclass_sets * 2 );
/* scan subclass set records */
for ( ; num_subclass_sets > 0; num_subclass_sets-- )
{
OTL_UInt offset = OTL_NEXT_USHORT( p );
if ( offset )
otl_sub_rule_set_validate( table + offset, lookup_count, valid );
}
}
break;
case 3:
{
OTL_UInt num_glyphs, num_subst, count;
OTL_CHECK( 4 );
num_glyphs = OTL_NEXT_USHORT( p );
num_subst = OTL_NEXT_USHORT( p );
OTL_CHECK( num_glyphs * 2 + num_subst * 4 );
for ( count = num_glyphs; count > 0; count-- )
otl_coverage_validate( table + OTL_NEXT_USHORT( p ), valid );
for ( ; num_subst > 0; num_subst-- )
{
if ( OTL_NEXT_USHORT( p ) >= num_glyphs )
OTL_INVALID_DATA;
if ( OTL_NEXT_USHORT( p ) >= lookup_count )
OTL_INVALID_DATA;
}
}
break;
default:
OTL_INVALID_DATA;
}
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** GSUB LOOKUP TYPE 6 *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/* used for both format 1 and 2 */
static void
otl_chain_sub_rule_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt num_backtrack_glyphs, num_input_glyphs, num_lookahead_glyphs;
OTL_UInt num_subst;
OTL_CHECK( 2 );
num_backtrack_glyphs = OTL_NEXT_USHORT( p );
OTL_CHECK( num_backtrack_glyphs * 2 + 2 );
p += num_backtrack_glyphs * 2;
num_input_glyphs = OTL_NEXT_USHORT( p );
if ( num_input_glyphs == 0 )
OTL_INVALID_DATA;
OTL_CHECK( num_input_glyphs * 2 );
p += ( num_input_glyphs - 1 ) * 2;
num_lookahead_glyphs = OTL_NEXT_USHORT( p );
OTL_CHECK( num_lookahead_glyphs * 2 + 2 );
p += num_lookahead_glyphs * 2;
num_subst = OTL_NEXT_USHORT( p );
OTL_CHECK( num_subst * 4 );
for ( ; num_subst > 0; num_subst-- )
{
if ( OTL_NEXT_USHORT( p ) >= num_input_glyphs )
OTL_INVALID_DATA;
if ( OTL_NEXT_USHORT( p ) >= lookup_count )
OTL_INVALID_DATA;
}
/* no need to check glyph indices/classes used as input for this */
/* context rule since even invalid glyph indices/classes return a */
/* meaningful result */
}
/* used for both format 1 and 2 */
static void
otl_chain_sub_rule_set_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt num_chain_subrules;
OTL_CHECK( 2 );
num_chain_subrules = OTL_NEXT_USHORT( p );
OTL_CHECK( num_chain_subrules * 2 );
/* scan chain subst rule records */
for ( ; num_chain_subrules > 0; num_chain_subrules-- )
otl_chain_sub_rule_validate( table + OTL_NEXT_USHORT( p ),
lookup_count, valid );
}
static void
otl_gsub_lookup6_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt format;
OTL_UNUSED( glyph_count );
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
switch ( format )
{
case 1:
{
OTL_UInt coverage, num_chain_subrulesets;
OTL_CHECK( 4 );
coverage = OTL_NEXT_USHORT( p );
num_chain_subrulesets = OTL_NEXT_USHORT( p );
otl_coverage_validate( table + coverage, valid );
OTL_CHECK( num_chain_subrulesets * 2 );
/* scan chain subrule set records */
for ( ; num_chain_subrulesets > 0; num_chain_subrulesets-- )
otl_chain_sub_rule_set_validate( table + OTL_NEXT_USHORT( p ),
lookup_count, valid );
}
break;
case 2:
{
OTL_UInt coverage, back_class, input_class, ahead_class;
OTL_UInt num_chain_subclass_sets;
OTL_CHECK( 10 );
coverage = OTL_NEXT_USHORT( p );
back_class = OTL_NEXT_USHORT( p );
input_class = OTL_NEXT_USHORT( p );
ahead_class = OTL_NEXT_USHORT( p );
num_chain_subclass_sets = OTL_NEXT_USHORT( p );
otl_coverage_validate( table + coverage, valid );
otl_class_definition_validate( table + back_class, valid );
otl_class_definition_validate( table + input_class, valid );
otl_class_definition_validate( table + ahead_class, valid );
OTL_CHECK( num_chain_subclass_sets * 2 );
/* scan chain subclass set records */
for ( ; num_chain_subclass_sets > 0; num_chain_subclass_sets-- )
{
OTL_UInt offset = OTL_NEXT_USHORT( p );
if ( offset )
otl_chain_sub_rule_set_validate( table + offset, lookup_count,
valid );
}
}
break;
case 3:
{
OTL_UInt num_backtrack_glyphs, num_input_glyphs;
OTL_UInt num_lookahead_glyphs, num_subst, count;
OTL_CHECK( 2 );
num_backtrack_glyphs = OTL_NEXT_USHORT( p );
OTL_CHECK( num_backtrack_glyphs * 2 + 2 );
for ( ; num_backtrack_glyphs > 0; num_backtrack_glyphs-- )
otl_coverage_validate( table + OTL_NEXT_USHORT( p ), valid );
num_input_glyphs = OTL_NEXT_USHORT( p );
OTL_CHECK( num_input_glyphs * 2 + 2 );
for ( count = num_input_glyphs; count > 0; count-- )
otl_coverage_validate( table + OTL_NEXT_USHORT( p ), valid );
num_lookahead_glyphs = OTL_NEXT_USHORT( p );
OTL_CHECK( num_lookahead_glyphs * 2 + 2 );
for ( ; num_lookahead_glyphs > 0; num_lookahead_glyphs-- )
otl_coverage_validate( table + OTL_NEXT_USHORT( p ), valid );
num_subst = OTL_NEXT_USHORT( p );
OTL_CHECK( num_subst * 4 );
for ( ; num_subst > 0; num_subst-- )
{
if ( OTL_NEXT_USHORT( p ) >= num_input_glyphs )
OTL_INVALID_DATA;
if ( OTL_NEXT_USHORT( p ) >= lookup_count )
OTL_INVALID_DATA;
}
}
break;
default:
OTL_INVALID_DATA;
}
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** GSUB LOOKUP TYPE 7 *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
static void
otl_gsub_lookup7_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt format;
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
switch ( format )
{
case 1:
{
OTL_UInt lookup_type, lookup_offset;
OTL_ValidateFunc validate;
OTL_CHECK( 6 );
lookup_type = OTL_NEXT_USHORT( p );
lookup_offset = OTL_NEXT_ULONG( p );
if ( lookup_type == 0 || lookup_type == 7 || lookup_type > 8 )
OTL_INVALID_DATA;
validate = otl_gsub_validate_funcs[lookup_type - 1];
validate( table + lookup_offset, lookup_count, glyph_count, valid );
}
break;
default:
OTL_INVALID_DATA;
}
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** GSUB LOOKUP TYPE 8 *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
static void
otl_gsub_lookup8_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table, coverage;
OTL_UInt format;
OTL_UInt num_backtrack_glyphs, num_lookahead_glyphs, num_glyphs;
OTL_UNUSED( lookup_count );
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
switch ( format )
{
case 1:
OTL_CHECK( 4 );
coverage = table + OTL_NEXT_USHORT( p );
num_backtrack_glyphs = OTL_NEXT_USHORT( p );
otl_coverage_validate( coverage, valid );
OTL_CHECK( num_backtrack_glyphs * 2 + 2 );
for ( ; num_backtrack_glyphs > 0; num_backtrack_glyphs-- )
otl_coverage_validate( table + OTL_NEXT_USHORT( p ), valid );
num_lookahead_glyphs = OTL_NEXT_USHORT( p );
OTL_CHECK( num_lookahead_glyphs * 2 + 2 );
for ( ; num_lookahead_glyphs > 0; num_lookahead_glyphs-- )
otl_coverage_validate( table + OTL_NEXT_USHORT( p ), valid );
num_glyphs = OTL_NEXT_USHORT( p );
if ( num_glyphs != otl_coverage_get_count( coverage ) )
OTL_INVALID_DATA;
OTL_CHECK( num_glyphs * 2 );
for ( ; num_glyphs > 0; num_glyphs-- )
if ( OTL_NEXT_USHORT( p ) >= glyph_count )
OTL_INVALID_DATA;
break;
default:
OTL_INVALID_DATA;
}
}
static OTL_ValidateFunc otl_gsub_validate_funcs[8] =
{
otl_gsub_lookup1_validate,
otl_gsub_lookup2_validate,
otl_gsub_lookup3_validate,
otl_gsub_lookup4_validate,
otl_gsub_lookup5_validate,
otl_gsub_lookup6_validate,
otl_gsub_lookup7_validate,
otl_gsub_lookup8_validate
};
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** GSUB TABLE *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
OTL_LOCALDEF( void )
otl_gsub_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt scripts, features, lookups;
OTL_CHECK( 10 );
if ( OTL_NEXT_USHORT( p ) != 0x10000UL )
OTL_INVALID_DATA;
scripts = OTL_NEXT_USHORT( p );
features = OTL_NEXT_USHORT( p );
lookups = OTL_NEXT_USHORT( p );
otl_lookup_list_validate( table + lookups, 8, otl_gsub_validate_funcs,
glyph_count, valid );
otl_feature_list_validate( table + features, table + lookups, valid );
otl_script_list_validate( table + scripts, table + features, valid );
}
/* END */