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Code Issues 9 Releases Wiki Activity

* src/otlayout/otlgpos.c (otl_gpos_lookup1_validate, 

otl_gpos_lookup2_validate, otl_gpos_lookup3_validate,
otl_gpos_lookup4_validate, otl_gpos_lookup5_validate,
otl_gpos_lookup6_validate, otl_gpos_lookup9_validate,
otl_gpos_validate): Update
function arguments.
(otl_gpos_lookup7_validate, otl_gpos_lookup8_validate): Update
function arguments.
Handle NULL offsets correctly.
Check sequence and lookup indices for format 3.
(otl_pos_rule_validate, otl_chain_pos_rule_validate): Add argument
to pass lookup count.
Check sequence and glyph indices.
(otl_gpos_subtable_validate): Update function arguments.
Update callers.

* src/otlayout/otlgpos.h: Updated.

* src/otlayout/otlgsub.c (otl_gsub_lookup1_validate,
otl_gsub_lookup3_validate, otl_gsub_lookup8_validate): Update
function arguments.
Add glyph index checks.
(otl_sequence_validate, otl_alternate_set_validate,
otl_ligature_validate): Add argument to pass glyph count.
Update callers.
Add glyph index check.
(otl_gsub_lookup2_validate, otl_gsub_lookup4_validate): Update
function arguments.
(otl_ligature_set_validate): Add argument to pass glyph count.
Update caller.
(otl_sub_class_rule_validate,
otl_sub_class_rule_set_validate): Removed.
(otl_sub_rule_validate, otl_chain_sub_rule_validate): Add argument
to pass lookup count.
Update callers.
Add lookup index check.
(otl_sub_rule_set_validate, otl_chain_sub_rule_set_validate): Add
argument to pass lookup count.
Update callers.
(otl_gsub_lookup5_validate): Update function arguments.
Handle NULL offsets correctly.
Don't call otl_sub_class_rule_set_validate but
otl_sub_rule_set_validate.
Check sequence and lookup indices for format 3.
(otl_gsub_lookup6_validate): Update function arguments.
Handle NULL offsets correctly.
Check sequence and lookup indices for format 3.
(otl_gsub_lookup7_validate, otl_gsub_validate): Update function
arguments.

* src/otlayout/otlgsub.h: Updated.

* src/otlayout/otlbase.c (otl_base_validate): Handle NULL offsets
correctly.

* src/otlayout/otlcommn.c (otl_class_definition_validate): Fix
compiler warning.
(otl_coverage_get_first, otl_coverage_get_last): New functions.
(otl_lookup_validate): Add arguments to pass lookup and glyph
counts.
Update callers.
(otl_lookup_list_validate): Add argument to pass glyph count.
Update callers.

* src/otlayout/otlcommn.h: Updated.

* src/otlayout/otljstf.c (otl_jstf_extender_validate,
otl_jstf_max_validate, otl_jstf_script_validate,
otl_jstf_priority_validate, otl_jstf_lang_validate): Add parameter
to validate glyph indices.
Update callers.
(otl_jstf_validate): Add parameter which specifies number of glyphs
in font.

* src/otlayout/otljstf.h: Updated.
This commit is contained in:
Werner Lemberg 2004-08-17 23:02:06 +00:00
parent b5a0a34be7
commit 46b5c4ac31
11 changed files with 486 additions and 155 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

78
ChangeLog
View File

@ -1,3 +1,81 @@
2004-08-16 Werner Lemberg <wl@gnu.org>
* src/otlayout/otlgpos.c (otl_gpos_lookup1_validate,
otl_gpos_lookup2_validate, otl_gpos_lookup3_validate,
otl_gpos_lookup4_validate, otl_gpos_lookup5_validate,
otl_gpos_lookup6_validate, otl_gpos_lookup9_validate,
otl_gpos_validate): Update
function arguments.
(otl_gpos_lookup7_validate, otl_gpos_lookup8_validate): Update
function arguments.
Handle NULL offsets correctly.
Check sequence and lookup indices for format 3.
(otl_pos_rule_validate, otl_chain_pos_rule_validate): Add argument
to pass lookup count.
Check sequence and glyph indices.
(otl_gpos_subtable_validate): Update function arguments.
Update callers.
* src/otlayout/otlgpos.h: Updated.
* src/otlayout/otlgsub.c (otl_gsub_lookup1_validate,
otl_gsub_lookup3_validate, otl_gsub_lookup8_validate): Update
function arguments.
Add glyph index checks.
(otl_sequence_validate, otl_alternate_set_validate,
otl_ligature_validate): Add argument to pass glyph count.
Update callers.
Add glyph index check.
(otl_gsub_lookup2_validate, otl_gsub_lookup4_validate): Update
function arguments.
(otl_ligature_set_validate): Add argument to pass glyph count.
Update caller.
(otl_sub_class_rule_validate,
otl_sub_class_rule_set_validate): Removed.
(otl_sub_rule_validate, otl_chain_sub_rule_validate): Add argument
to pass lookup count.
Update callers.
Add lookup index check.
(otl_sub_rule_set_validate, otl_chain_sub_rule_set_validate): Add
argument to pass lookup count.
Update callers.
(otl_gsub_lookup5_validate): Update function arguments.
Handle NULL offsets correctly.
Don't call otl_sub_class_rule_set_validate but
otl_sub_rule_set_validate.
Check sequence and lookup indices for format 3.
(otl_gsub_lookup6_validate): Update function arguments.
Handle NULL offsets correctly.
Check sequence and lookup indices for format 3.
(otl_gsub_lookup7_validate, otl_gsub_validate): Update function
arguments.
* src/otlayout/otlgsub.h: Updated.
* src/otlayout/otlbase.c (otl_base_validate): Handle NULL offsets
correctly.
* src/otlayout/otlcommn.c (otl_class_definition_validate): Fix
compiler warning.
(otl_coverage_get_first, otl_coverage_get_last): New functions.
(otl_lookup_validate): Add arguments to pass lookup and glyph
counts.
Update callers.
(otl_lookup_list_validate): Add argument to pass glyph count.
Update callers.
* src/otlayout/otlcommn.h: Updated.
* src/otlayout/otljstf.c (otl_jstf_extender_validate,
otl_jstf_max_validate, otl_jstf_script_validate,
otl_jstf_priority_validate, otl_jstf_lang_validate): Add parameter
to validate glyph indices.
Update callers.
(otl_jstf_validate): Add parameter which specifies number of glyphs
in font.
* src/otlayout/otljstf.h: Updated.
2004-08-15 Werner Lemberg <wl@gnu.org>
* src/otlayout/otlgpos.c (otl_liga_mark2_validate): Add parameter

2
src/otlayout/otlayout.h
View File

@ -189,6 +189,8 @@ OTL_BEGIN_HEADER
} OTL_ValidatorRec;
typedef void (*OTL_ValidateFunc)( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid );
OTL_API( void )

12
src/otlayout/otlbase.c
View File

@ -208,6 +208,7 @@
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt val;
OTL_CHECK( 6 );
@ -215,8 +216,15 @@
if ( OTL_NEXT_ULONG( p ) != 0x10000UL )
OTL_INVALID_DATA;
otl_axis_table_validate( table + OTL_NEXT_USHORT( p ), valid );
otl_axis_table_validate( table + OTL_NEXT_USHORT( p ), valid );
/* validate horizontal axis table */
val = OTL_NEXT_USHORT( p );
if ( val )
otl_axis_table_validate( table + val, valid );
/* validate vertical axis table */
val = OTL_NEXT_USHORT( p );
if ( val )
otl_axis_table_validate( table + val, valid );
}

59
src/otlayout/otlcommn.c
View File

@ -86,6 +86,47 @@
}
OTL_LOCALDEF( OTL_UInt )
otl_coverage_get_first( OTL_Bytes table )
{
OTL_Bytes p = table;
p += 4; /* skip format and count */
return OTL_NEXT_USHORT( p );
}
OTL_LOCALDEF( OTL_UInt )
otl_coverage_get_last( OTL_Bytes table )
{
OTL_Bytes p = table;
OTL_UInt format = OTL_NEXT_USHORT( p );
OTL_UInt count = OTL_NEXT_USHORT( p );
OTL_UInt result;
switch ( format )
{
case 1:
p += ( count - 1 ) * 2;
result = OTL_NEXT_USHORT( p );
break;
case 2:
p += ( count - 1 ) * 6 + 2;
result = OTL_NEXT_USHORT( p );
break;
default:
;
}
return result;
}
OTL_LOCALDEF( OTL_UInt )
otl_coverage_get_count( OTL_Bytes table )
{
@ -215,14 +256,15 @@
{
case 1:
{
OTL_UInt num_glyphs, start = OTL_NEXT_USHORT( p );
OTL_UInt num_glyphs;
p += 2; /* skip start_glyph */
OTL_CHECK( 2 );
num_glyphs = OTL_NEXT_USHORT( p );
OTL_CHECK( num_glyphs * 2 );
}
break;
@ -442,6 +484,8 @@
otl_lookup_validate( OTL_Bytes table,
OTL_UInt type_count,
OTL_ValidateFunc* type_funcs,
OTL_UInt lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -463,7 +507,8 @@
/* scan subtables */
for ( ; num_subtables > 0; num_subtables-- )
validate( table + OTL_NEXT_USHORT( p ), valid );
validate( table + OTL_NEXT_USHORT( p ), lookup_count, glyph_count,
valid );
}
@ -511,10 +556,11 @@
otl_lookup_list_validate( OTL_Bytes table,
OTL_UInt type_count,
OTL_ValidateFunc* type_funcs,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt num_lookups;
OTL_UInt num_lookups, count;
OTL_CHECK( 2 );
@ -522,9 +568,10 @@
OTL_CHECK( 2 * num_lookups );
/* scan lookup records */
for ( ; num_lookups > 0; num_lookups-- )
for ( count = num_lookups; count > 0; count-- )
otl_lookup_validate( table + OTL_NEXT_USHORT( p ),
type_count, type_funcs, valid );
type_count, type_funcs,
num_lookups, glyph_count, valid );
}

11
src/otlayout/otlcommn.h
View File

@ -37,6 +37,14 @@ OTL_BEGIN_HEADER
otl_coverage_validate( OTL_Bytes table,
OTL_Validator valid );
/* return first covered glyph */
OTL_LOCAL( OTL_UInt )
otl_coverage_get_first( OTL_Bytes table );
/* return last covered glyph */
OTL_LOCAL( OTL_UInt )
otl_coverage_get_last( OTL_Bytes table );
/* return number of covered glyphs */
OTL_LOCAL( OTL_UInt )
otl_coverage_get_count( OTL_Bytes table );
@ -116,6 +124,8 @@ OTL_BEGIN_HEADER
otl_lookup_validate( OTL_Bytes table,
OTL_UInt type_count,
OTL_ValidateFunc* type_funcs,
OTL_UInt lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid );
/* return number of sub-tables in a lookup */
@ -143,6 +153,7 @@ OTL_BEGIN_HEADER
otl_lookup_list_validate( OTL_Bytes table,
OTL_UInt type_count,
OTL_ValidateFunc* type_funcs,
OTL_UInt glyph_count,
OTL_Validator valid );
#if 0

147
src/otlayout/otlgpos.c
View File

@ -173,11 +173,16 @@
static void
otl_gpos_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_UNUSED( glyph_count );
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
@ -270,11 +275,16 @@
static void
otl_gpos_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_UNUSED( glyph_count );
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
@ -354,11 +364,16 @@
static void
otl_gpos_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_UNUSED( glyph_count );
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
@ -430,11 +445,16 @@
static void
otl_gpos_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_UNUSED( glyph_count );
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
@ -466,6 +486,7 @@
}
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
@ -529,11 +550,16 @@
static void
otl_gpos_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( lookup_count );
OTL_UNUSED( glyph_count );
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
@ -576,11 +602,16 @@
static void
otl_gpos_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( lookup_count );
OTL_UNUSED( glyph_count );
OTL_CHECK( 2 );
format = OTL_NEXT_USHORT( p );
@ -623,6 +654,7 @@
/* used for both format 1 and 2 */
static void
otl_pos_rule_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -638,7 +670,14 @@
OTL_CHECK( ( num_glyphs - 1 ) * 2 + num_pos * 4 );
/* XXX: check pos lookups */
for ( ; num_pos > 0; num_pos-- )
{
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 */
@ -649,6 +688,7 @@
/* used for both format 1 and 2 */
static void
otl_pos_rule_set_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -662,17 +702,22 @@
/* scan posrule records */
for ( ; num_posrules > 0; num_posrules-- )
otl_pos_rule_validate( table + OTL_NEXT_USHORT( p ), valid );
otl_pos_rule_validate( table + OTL_NEXT_USHORT( p ), lookup_count,
valid );
}
static void
otl_gpos_lookup7_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 );
@ -693,7 +738,8 @@
/* scan posrule set records */
for ( ; num_posrule_sets > 0; num_posrule_sets-- )
otl_pos_rule_set_validate( table + OTL_NEXT_USHORT( p ), valid );
otl_pos_rule_set_validate( table + OTL_NEXT_USHORT( p ),
lookup_count, valid );
}
break;
@ -714,13 +760,19 @@
/* scan pos class set rules */
for ( ; num_posclass_sets > 0; num_posclass_sets-- )
otl_pos_rule_set_validate( table + OTL_NEXT_USHORT( p ), valid );
{
OTL_UInt offset = OTL_NEXT_USHORT( p );
if ( offset )
otl_pos_rule_set_validate( table + offset, lookup_count, valid );
}
}
break;
case 3:
{
OTL_UInt num_glyphs, num_pos;
OTL_UInt num_glyphs, num_pos, count;
OTL_CHECK( 4 );
@ -729,10 +781,17 @@
OTL_CHECK( num_glyphs * 2 + num_pos * 4 );
for ( ; num_glyphs > 0; num_glyphs-- )
for ( count = num_glyphs; count > 0; count-- )
otl_coverage_validate( table + OTL_NEXT_USHORT( p ), valid );
/* XXX: check pos lookups */
for ( ; num_pos > 0; num_pos-- )
{
if ( OTL_NEXT_USHORT( p ) >= num_glyphs )
OTL_INVALID_DATA;
if ( OTL_NEXT_USHORT( p ) >= lookup_count )
OTL_INVALID_DATA;
}
}
break;
@ -753,6 +812,7 @@
/* used for both format 1 and 2 */
static void
otl_chain_pos_rule_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -780,37 +840,54 @@
num_pos = OTL_NEXT_USHORT( p );
OTL_CHECK( num_pos * 4 );
/* XXX: check pos lookups */
for ( ; num_pos > 0; num_pos-- )
{
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_pos_rule_set_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt count;
OTL_UInt num_chain_subrules;
OTL_CHECK( 2 );
count = OTL_NEXT_USHORT( p );
num_chain_subrules = OTL_NEXT_USHORT( p );
OTL_CHECK( 2 * count );
OTL_CHECK( num_chain_subrules * 2 );
/* scan chain pos rule records */
for ( ; count > 0; count-- )
otl_chain_pos_rule_validate( table + OTL_NEXT_USHORT( p ), valid );
for ( ; num_chain_subrules > 0; num_chain_subrules-- )
otl_chain_pos_rule_validate( table + OTL_NEXT_USHORT( p ),
lookup_count, valid );
}
static void
otl_gpos_lookup8_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 );
@ -832,7 +909,7 @@
/* scan chain pos ruleset records */
for ( ; num_chain_pos_rulesets > 0; num_chain_pos_rulesets-- )
otl_chain_pos_rule_set_validate( table + OTL_NEXT_USHORT( p ),
valid );
lookup_count, valid );
}
break;
@ -859,33 +936,39 @@
/* scan chainpos class set records */
for ( ; num_chainpos_class_sets > 0; num_chainpos_class_sets-- )
otl_chain_pos_rule_set_validate( table + OTL_NEXT_USHORT( p ),
valid );
{
OTL_UInt offset = OTL_NEXT_USHORT( p );
if ( offset )
otl_chain_pos_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_pos;
OTL_UInt num_lookahead_glyphs, num_pos, count;
OTL_CHECK( 2 );
num_backtrack_glyphs = OTL_NEXT_USHORT( p );
OTL_CHECK( 2 * num_backtrack_glyphs + 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( 2 * num_input_glyphs + 2 );
OTL_CHECK( num_input_glyphs * 2 + 2 );
for ( ; num_input_glyphs > 0; num_input_glyphs-- )
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( 2 * num_lookahead_glyphs + 2 );
OTL_CHECK( num_lookahead_glyphs * 2 + 2 );
for ( ; num_lookahead_glyphs > 0; num_lookahead_glyphs-- )
otl_coverage_validate( table + OTL_NEXT_USHORT( p ), valid );
@ -893,7 +976,14 @@
num_pos = OTL_NEXT_USHORT( p );
OTL_CHECK( num_pos * 4 );
/* XXX: check pos lookups */
for ( ; num_pos > 0; num_pos-- )
{
if ( OTL_NEXT_USHORT( p ) >= num_input_glyphs )
OTL_INVALID_DATA;
if ( OTL_NEXT_USHORT( p ) >= lookup_count )
OTL_INVALID_DATA;
}
}
break;
@ -913,6 +1003,8 @@
static void
otl_gpos_lookup9_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -937,7 +1029,7 @@
OTL_INVALID_DATA;
validate = otl_gpos_validate_funcs[lookup_type - 1];
validate( table + lookup_offset, valid );
validate( table + lookup_offset, lookup_count, glyph_count, valid );
}
break;
@ -963,9 +1055,11 @@
OTL_LOCALDEF( void )
otl_gpos_subtable_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
otl_lookup_list_validate( table, 9, otl_gpos_validate_funcs, valid );
otl_lookup_list_validate( table, 9, otl_gpos_validate_funcs,
glyph_count, valid );
}
@ -979,6 +1073,7 @@
OTL_LOCALDEF( void )
otl_gpos_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -994,7 +1089,7 @@
features = OTL_NEXT_USHORT( p );
lookups = OTL_NEXT_USHORT( p );
otl_gpos_subtable_validate( table + lookups, valid );
otl_gpos_subtable_validate( table + lookups, glyph_count, valid );
otl_feature_list_validate( table + features, table + lookups, valid );
otl_script_list_validate( table + scripts, table + features, valid );
}

2
src/otlayout/otlgpos.h
View File

@ -26,10 +26,12 @@ OTL_BEGIN_HEADER
OTL_LOCAL( void )
otl_gpos_subtable_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid );
OTL_LOCAL( void )
otl_gpos_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid );

292
src/otlayout/otlgsub.c
View File

@ -57,11 +57,15 @@
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 );
@ -69,12 +73,26 @@
switch ( format )
{
case 1:
OTL_CHECK( 4 );
{
OTL_Bytes coverage;
OTL_Int delta;
OTL_Long idx;
otl_coverage_validate( table + OTL_NEXT_USHORT( p ), valid );
/* skip delta glyph ID */
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:
@ -88,11 +106,11 @@
otl_coverage_validate( table + coverage, valid );
OTL_CHECK( 2 * num_glyphs );
OTL_CHECK( num_glyphs * 2 );
/* We don't check that there are at most `num_glyphs' */
/* elements in the coverage table. This is delayed */
/* to the lookup function. */
for ( ; num_glyphs > 0; num_glyphs-- )
if ( OTL_NEXT_USHORT( p ) >= glyph_count )
OTL_INVALID_DATA;
}
break;
@ -198,6 +216,7 @@
static void
otl_sequence_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -207,22 +226,28 @@
OTL_CHECK( 2 );
num_glyphs = OTL_NEXT_USHORT( p );
/* XXX: according to the spec, `num_glyphs' should be > 0; */
/* we can deal with these cases pretty well, however */
/* according to the specification, `num_glyphs' should be > 0; */
/* we can deal with these cases pretty well, however */
OTL_CHECK( 2 * num_glyphs );
OTL_CHECK( num_glyphs * 2 );
/* XXX: check glyph indices */
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 );
@ -243,7 +268,8 @@
/* scan sequence records */
for ( ; num_sequences > 0; num_sequences-- )
otl_sequence_validate( table + OTL_NEXT_USHORT( p ), valid );
otl_sequence_validate( table + OTL_NEXT_USHORT( p ), glyph_count,
valid );
}
break;
@ -329,28 +355,35 @@
static void
otl_alternate_set_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt count;
OTL_UInt num_glyphs;
OTL_CHECK( 2 );
count = OTL_NEXT_USHORT( p );
num_glyphs = OTL_NEXT_USHORT( p );
OTL_CHECK( 2 * count );
OTL_CHECK( num_glyphs * 2 );
/* XXX: check glyph indices */
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 );
@ -367,11 +400,12 @@
otl_coverage_validate( table + coverage, valid );
OTL_CHECK( 2 * num_alternate_sets );
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 ), valid );
otl_alternate_set_validate( table + OTL_NEXT_USHORT( p ),
glyph_count, valid );
}
break;
@ -442,6 +476,7 @@
static void
otl_ligature_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -455,14 +490,19 @@
if ( num_components == 0 )
OTL_INVALID_DATA;
OTL_CHECK( 2 * ( num_components - 1 ) );
num_components--;
/* XXX: check glyph indices */
OTL_CHECK( num_components * 2 );
for ( ; num_components > 0; num_components-- )
if ( OTL_NEXT_USHORT( p ) >= glyph_count )
OTL_INVALID_DATA;
}
static void
otl_ligature_set_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -472,21 +512,26 @@
OTL_CHECK( 2 );
num_ligatures = OTL_NEXT_USHORT( p );
OTL_CHECK( 2 * num_ligatures );
OTL_CHECK( num_ligatures * 2 );
/* scan ligature records */
for ( ; num_ligatures > 0; num_ligatures-- )
otl_ligature_validate( table + OTL_NEXT_USHORT( p ), valid );
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 );
@ -503,11 +548,12 @@
otl_coverage_validate( table + coverage, valid );
OTL_CHECK( 2 * num_ligsets );
OTL_CHECK( num_ligsets * 2 );
/* scan ligature set records */
for ( ; num_ligsets > 0; num_ligsets-- )
otl_ligature_set_validate( table + OTL_NEXT_USHORT( p ), valid );
otl_ligature_set_validate( table + OTL_NEXT_USHORT( p ),
glyph_count, valid );
}
break;
@ -525,8 +571,10 @@
/*************************************************************************/
/*************************************************************************/
/* 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;
@ -542,12 +590,25 @@
OTL_CHECK( ( num_glyphs - 1 ) * 2 + num_subst * 4 );
/* XXX: check glyph indices and subst lookups */
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;
@ -557,64 +618,26 @@
OTL_CHECK( 2 );
num_subrules = OTL_NEXT_USHORT( p );
OTL_CHECK( 2 * num_subrules );
/* scan sub rule records */
for ( ; num_subrules > 0; num_subrules-- )
otl_sub_rule_validate( table + OTL_NEXT_USHORT( p ), valid );
}
static void
otl_sub_class_rule_validate( OTL_Bytes table,
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 );
/* XXX: check subst lookups */
/* no need to check glyph indices used as input for this context */
/* rule since even invalid glyph indices return a meaningful result */
}
static void
otl_sub_class_rule_set_validate( OTL_Bytes table,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt num_subrules;
OTL_CHECK( 2 );
num_subrules = OTL_NEXT_USHORT( p );
OTL_CHECK( 2 * num_subrules );
OTL_CHECK( num_subrules * 2 );
/* scan subrule records */
for ( ; num_subrules > 0; num_subrules-- )
otl_sub_class_rule_validate( table + OTL_NEXT_USHORT( p ), valid );
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 );
@ -631,11 +654,12 @@
otl_coverage_validate( table + coverage, valid );
OTL_CHECK( 2 * num_subrulesets );
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 ), valid );
otl_sub_rule_set_validate( table + OTL_NEXT_USHORT( p ),
lookup_count, valid );
}
break;
@ -652,30 +676,42 @@
otl_coverage_validate( table + coverage, valid );
otl_class_definition_validate( table + class_def, valid );
OTL_CHECK( 2 * num_subclass_sets );
OTL_CHECK( num_subclass_sets * 2 );
/* scan subclass set records */
for ( ; num_subclass_sets > 0; num_subclass_sets-- )
otl_sub_class_rule_set_validate( table + OTL_NEXT_USHORT( p ),
valid );
{
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;
OTL_UInt num_glyphs, num_subst, count;
OTL_CHECK( 4 );
num_glyphs = OTL_NEXT_USHORT( p );
num_subst = OTL_NEXT_USHORT( p );
OTL_CHECK( 2 * num_glyphs + 4 * num_subst );
OTL_CHECK( num_glyphs * 2 + num_subst * 4 );
for ( ; num_glyphs > 0; num_glyphs-- )
for ( count = num_glyphs; count > 0; count-- )
otl_coverage_validate( table + OTL_NEXT_USHORT( p ), valid );
/* XXX: check subst lookups */
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;
@ -696,6 +732,7 @@
/* 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;
@ -706,33 +743,42 @@
OTL_CHECK( 2 );
num_backtrack_glyphs = OTL_NEXT_USHORT( p );
OTL_CHECK( 2 * num_backtrack_glyphs + 2 );
p += 2 * num_backtrack_glyphs;
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( 2 * num_input_glyphs );
p += 2 * ( num_input_glyphs - 1 );
OTL_CHECK( num_input_glyphs * 2 );
p += ( num_input_glyphs - 1 ) * 2;
num_lookahead_glyphs = OTL_NEXT_USHORT( p );
OTL_CHECK( 2 * num_lookahead_glyphs + 2 );
p += 2 * num_lookahead_glyphs;
OTL_CHECK( num_lookahead_glyphs * 2 + 2 );
p += num_lookahead_glyphs * 2;
num_subst = OTL_NEXT_USHORT( p );
OTL_CHECK( 4 * num_subst );
OTL_CHECK( num_subst * 4 );
/* XXX: check subst lookups */
for ( ; num_subst > 0; num_subst-- )
{
if ( OTL_NEXT_USHORT( p ) >= num_input_glyphs )
OTL_INVALID_DATA;
/* no need to check glyph indices used as input for this context */
/* rule since even invalid glyph indices return a meaningful result */
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;
@ -742,21 +788,26 @@
OTL_CHECK( 2 );
num_chain_subrules = OTL_NEXT_USHORT( p );
OTL_CHECK( 2 * num_chain_subrules );
OTL_CHECK( num_chain_subrules * 2 );
/* scan chain subrule records */
/* scan chain subst rule records */
for ( ; num_chain_subrules > 0; num_chain_subrules-- )
otl_chain_sub_rule_validate( table + OTL_NEXT_USHORT( p ), valid );
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 );
@ -773,12 +824,12 @@
otl_coverage_validate( table + coverage, valid );
OTL_CHECK( 2 * num_chain_subrulesets );
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 ),
valid );
lookup_count, valid );
}
break;
@ -801,37 +852,43 @@
otl_class_definition_validate( table + input_class, valid );
otl_class_definition_validate( table + ahead_class, valid );
OTL_CHECK( 2 * num_chain_subclass_sets );
OTL_CHECK( num_chain_subclass_sets * 2 );
/* scan chain subclass set records */
for ( ; num_chain_subclass_sets > 0; num_chain_subclass_sets-- )
otl_chain_sub_rule_set_validate( table + OTL_NEXT_USHORT( p ),
valid );
{
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;
OTL_UInt num_lookahead_glyphs, num_subst, count;
OTL_CHECK( 2 );
num_backtrack_glyphs = OTL_NEXT_USHORT( p );
OTL_CHECK( 2 * num_backtrack_glyphs + 2 );
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( 2 * num_input_glyphs + 2 );
OTL_CHECK( num_input_glyphs * 2 + 2 );
for ( ; num_input_glyphs > 0; num_input_glyphs-- )
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( 2 * num_lookahead_glyphs + 2 );
OTL_CHECK( num_lookahead_glyphs * 2 + 2 );
for ( ; num_lookahead_glyphs > 0; num_lookahead_glyphs-- )
otl_coverage_validate( table + OTL_NEXT_USHORT( p ), valid );
@ -839,7 +896,14 @@
num_subst = OTL_NEXT_USHORT( p );
OTL_CHECK( num_subst * 4 );
/* XXX: check subst lookups */
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;
@ -859,6 +923,8 @@
static void
otl_gsub_lookup7_validate( OTL_Bytes table,
OTL_UInt lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -883,7 +949,7 @@
OTL_INVALID_DATA;
validate = otl_gsub_validate_funcs[lookup_type - 1];
validate( table + lookup_offset, valid );
validate( table + lookup_offset, lookup_count, glyph_count, valid );
}
break;
@ -903,12 +969,16 @@
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 );
@ -922,13 +992,13 @@
otl_coverage_validate( coverage, valid );
OTL_CHECK( 2 * num_backtrack_glyphs + 2 );
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( 2 * num_lookahead_glyphs + 2 );
OTL_CHECK( num_lookahead_glyphs * 2 + 2 );
for ( ; num_lookahead_glyphs > 0; num_lookahead_glyphs-- )
otl_coverage_validate( table + OTL_NEXT_USHORT( p ), valid );
@ -937,9 +1007,12 @@
if ( num_glyphs != otl_coverage_get_count( coverage ) )
OTL_INVALID_DATA;
OTL_CHECK( 2 * num_glyphs );
OTL_CHECK( num_glyphs * 2 );
for ( ; num_glyphs > 0; num_glyphs-- )
if ( OTL_NEXT_USHORT( p ) >= glyph_count )
OTL_INVALID_DATA;
/* XXX: check glyph indices */
break;
default:
@ -971,6 +1044,7 @@
OTL_LOCALDEF( void )
otl_gsub_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -987,7 +1061,7 @@
lookups = OTL_NEXT_USHORT( p );
otl_lookup_list_validate( table + lookups, 8, otl_gsub_validate_funcs,
valid );
glyph_count, valid );
otl_feature_list_validate( table + features, table + lookups, valid );
otl_script_list_validate( table + scripts, table + features, valid );
}

1
src/otlayout/otlgsub.h
View File

@ -40,6 +40,7 @@ OTL_BEGIN_HEADER
OTL_LOCAL( void )
otl_gsub_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid );

30
src/otlayout/otljstf.c
View File

@ -23,6 +23,7 @@
static void
otl_jstf_extender_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -35,7 +36,9 @@
OTL_CHECK( num_glyphs * 2 );
/* XXX: check glyph indices */
for ( ; num_glyphs > 0; num_glyphs-- )
if ( OTL_NEXT_USHORT( p ) >= glyph_count )
OTL_INVALID_DATA;
}
@ -63,6 +66,7 @@
static void
otl_jstf_max_validate( OTL_Bytes table,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -76,7 +80,8 @@
/* scan subtable records */
for ( ; num_lookups > 0; num_lookups-- )
/* XXX: check lookup types? */
otl_gpos_subtable_validate( table + OTL_NEXT_USHORT( p ), valid );
otl_gpos_subtable_validate( table + OTL_NEXT_USHORT( p ), glyph_count,
valid );
}
@ -84,6 +89,7 @@
otl_jstf_priority_validate( OTL_Bytes table,
OTL_UInt gsub_lookup_count,
OTL_UInt gpos_lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -117,7 +123,7 @@
/* shrinkage JSTF max */
val = OTL_NEXT_USHORT( p );
if ( val )
otl_jstf_max_validate( table + val, valid );
otl_jstf_max_validate( table + val, glyph_count, valid );
/* extension GSUB enable/disable */
val = OTL_NEXT_USHORT( p );
@ -144,7 +150,7 @@
/* extension JSTF max */
val = OTL_NEXT_USHORT( p );
if ( val )
otl_jstf_max_validate( table + val, valid );
otl_jstf_max_validate( table + val, glyph_count, valid );
}
@ -152,6 +158,7 @@
otl_jstf_lang_validate( OTL_Bytes table,
OTL_UInt gsub_lookup_count,
OTL_UInt gpos_lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -166,7 +173,7 @@
for ( ; num_priorities > 0; num_priorities-- )
otl_jstf_priority_validate( table + OTL_NEXT_USHORT( p ),
gsub_lookup_count, gpos_lookup_count,
valid );
glyph_count, valid );
}
@ -174,6 +181,7 @@
otl_jstf_script_validate( OTL_Bytes table,
OTL_UInt gsub_lookup_count,
OTL_UInt gpos_lookup_count,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -186,11 +194,12 @@
num_langsys = OTL_NEXT_USHORT( p );
if ( extender )
otl_jstf_extender_validate( table + extender, valid );
otl_jstf_extender_validate( table + extender, glyph_count, valid );
if ( default_lang )
otl_jstf_lang_validate( table + default_lang,
gsub_lookup_count, gpos_lookup_count, valid );
gsub_lookup_count, gpos_lookup_count,
glyph_count, valid );
OTL_CHECK( 6 * num_langsys );
@ -200,7 +209,8 @@
p += 4; /* skip tag */
otl_jstf_lang_validate( table + OTL_NEXT_USHORT( p ),
gsub_lookup_count, gpos_lookup_count, valid );
gsub_lookup_count, gpos_lookup_count,
glyph_count, valid );
}
}
@ -209,6 +219,7 @@
otl_jstf_validate( OTL_Bytes table,
OTL_Bytes gsub,
OTL_Bytes gpos,
OTL_UInt glyph_count,
OTL_Validator valid )
{
OTL_Bytes p = table;
@ -239,7 +250,8 @@
p += 4; /* skip tag */
otl_jstf_script_validate( table + OTL_NEXT_USHORT( p ),
gsub_lookup_count, gpos_lookup_count, valid );
gsub_lookup_count, gpos_lookup_count,
glyph_count, valid );
}
}

7
src/otlayout/otljstf.h
View File

@ -25,13 +25,14 @@
OTL_BEGIN_HEADER
/* validate JSTF table */
/* GSUB and GPOS tables must already be validated; if table is */
/* missing, set value to 0 */
/* validate JSTF table */
/* GSUB and GPOS tables should already be validated; */
/* if missing, set corresponding argument to 0 */
OTL_LOCAL( void )
otl_jstf_validate( OTL_Bytes table,
OTL_Bytes gsub,
OTL_Bytes gpos,
OTL_UInt glyph_count,
OTL_Validator valid );