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/****************************************************************************
*
* gxvmorx1.c
*
* TrueTypeGX/AAT morx table validation
* body for type1 (Contextual Substitution) subtable.
*
* Copyright (C) 2005-2024 by
* suzuki toshiya, Masatake YAMATO, Red Hat K.K.,
* 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.
*
*/
/****************************************************************************
*
* gxvalid is derived from both gxlayout module and otvalid module.
* Development of gxlayout is supported by the Information-technology
* Promotion Agency(IPA), Japan.
*
*/
#include "gxvmorx.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 gxvmorx
typedef struct GXV_morx_subtable_type1_StateOptRec_
{
FT_ULong substitutionTable;
FT_ULong substitutionTable_length;
FT_UShort substitutionTable_num_lookupTables;
} GXV_morx_subtable_type1_StateOptRec,
*GXV_morx_subtable_type1_StateOptRecData;
#define GXV_MORX_SUBTABLE_TYPE1_HEADER_SIZE \
( GXV_STATETABLE_HEADER_SIZE + 2 )
static void
gxv_morx_subtable_type1_substitutionTable_load( FT_Bytes table,
FT_Bytes limit,
GXV_Validator gxvalid )
{
FT_Bytes p = table;
GXV_morx_subtable_type1_StateOptRecData optdata =
(GXV_morx_subtable_type1_StateOptRecData)gxvalid->xstatetable.optdata;
GXV_LIMIT_CHECK( 2 );
optdata->substitutionTable = FT_NEXT_USHORT( p );
}
static void
gxv_morx_subtable_type1_subtable_setup( FT_ULong table_size,
FT_ULong classTable,
FT_ULong stateArray,
FT_ULong entryTable,
FT_ULong* classTable_length_p,
FT_ULong* stateArray_length_p,
FT_ULong* entryTable_length_p,
GXV_Validator gxvalid )
{
FT_ULong o[4];
FT_ULong *l[4];
FT_ULong buff[5];
GXV_morx_subtable_type1_StateOptRecData optdata =
(GXV_morx_subtable_type1_StateOptRecData)gxvalid->xstatetable.optdata;
o[0] = classTable;
o[1] = stateArray;
o[2] = entryTable;
o[3] = optdata->substitutionTable;
l[0] = classTable_length_p;
l[1] = stateArray_length_p;
l[2] = entryTable_length_p;
l[3] = &(optdata->substitutionTable_length);
gxv_set_length_by_ulong_offset( o, l, buff, 4, table_size, gxvalid );
}
static void
gxv_morx_subtable_type1_entry_validate(
FT_UShort state,
FT_UShort flags,
GXV_StateTable_GlyphOffsetCPtr glyphOffset_p,
FT_Bytes table,
FT_Bytes limit,
GXV_Validator gxvalid )
{
#ifdef GXV_LOAD_TRACE_VARS
FT_UShort setMark;
FT_UShort dontAdvance;
#endif
FT_UShort reserved;
FT_Short markIndex;
FT_Short currentIndex;
GXV_morx_subtable_type1_StateOptRecData optdata =
(GXV_morx_subtable_type1_StateOptRecData)gxvalid->xstatetable.optdata;
FT_UNUSED( state );
FT_UNUSED( table );
FT_UNUSED( limit );
#ifdef GXV_LOAD_TRACE_VARS
setMark = (FT_UShort)( ( flags >> 15 ) & 1 );
dontAdvance = (FT_UShort)( ( flags >> 14 ) & 1 );
#endif
reserved = (FT_UShort)( flags & 0x3FFF );
markIndex = (FT_Short)( glyphOffset_p->ul >> 16 );
currentIndex = (FT_Short)( glyphOffset_p->ul );
GXV_TRACE(( " setMark=%01d dontAdvance=%01d\n",
setMark, dontAdvance ));
if ( 0 < reserved )
{
GXV_TRACE(( " non-zero bits found in reserved range\n" ));
GXV_SET_ERR_IF_PARANOID( FT_INVALID_DATA );
}
GXV_TRACE(( "markIndex = %d, currentIndex = %d\n",
markIndex, currentIndex ));
if ( optdata->substitutionTable_num_lookupTables < markIndex + 1 )
optdata->substitutionTable_num_lookupTables =
(FT_UShort)( markIndex + 1 );
if ( optdata->substitutionTable_num_lookupTables < currentIndex + 1 )
optdata->substitutionTable_num_lookupTables =
(FT_UShort)( currentIndex + 1 );
}
static void
gxv_morx_subtable_type1_LookupValue_validate( FT_UShort glyph,
GXV_LookupValueCPtr value_p,
GXV_Validator gxvalid )
{
FT_UNUSED( glyph ); /* for the non-debugging case */
GXV_TRACE(( "morx subtable type1 subst.: %d -> %d\n", glyph, value_p->u ));
if ( value_p->u > gxvalid->face->num_glyphs )
FT_INVALID_GLYPH_ID;
}
static GXV_LookupValueDesc
gxv_morx_subtable_type1_LookupFmt4_transit(
FT_UShort relative_gindex,
GXV_LookupValueCPtr base_value_p,
FT_Bytes lookuptbl_limit,
GXV_Validator gxvalid )
{
FT_Bytes p;
FT_Bytes limit;
FT_UShort offset;
GXV_LookupValueDesc value;
/* XXX: check range? */
offset = (FT_UShort)( base_value_p->u +
relative_gindex * sizeof ( FT_UShort ) );
p = gxvalid->lookuptbl_head + offset;
limit = lookuptbl_limit;
GXV_LIMIT_CHECK ( 2 );
value.u = FT_NEXT_USHORT( p );
return value;
}
/*
* TODO: length should be limit?
**/
static void
gxv_morx_subtable_type1_substitutionTable_validate( FT_Bytes table,
FT_Bytes limit,
GXV_Validator gxvalid )
{
FT_Bytes p = table;
FT_UShort i;
GXV_morx_subtable_type1_StateOptRecData optdata =
(GXV_morx_subtable_type1_StateOptRecData)gxvalid->xstatetable.optdata;
/* TODO: calculate offset/length for each lookupTables */
gxvalid->lookupval_sign = GXV_LOOKUPVALUE_UNSIGNED;
gxvalid->lookupval_func = gxv_morx_subtable_type1_LookupValue_validate;
gxvalid->lookupfmt4_trans = gxv_morx_subtable_type1_LookupFmt4_transit;
for ( i = 0; i < optdata->substitutionTable_num_lookupTables; i++ )
{
FT_ULong offset;
GXV_LIMIT_CHECK( 4 );
offset = FT_NEXT_ULONG( p );
gxv_LookupTable_validate( table + offset, limit, gxvalid );
}
/* TODO: overlapping of lookupTables in substitutionTable */
}
/*
* subtable for Contextual glyph substitution is a modified StateTable.
* In addition to classTable, stateArray, entryTable, the field
* `substitutionTable' is added.
*/
FT_LOCAL_DEF( void )
gxv_morx_subtable_type1_validate( FT_Bytes table,
FT_Bytes limit,
GXV_Validator gxvalid )
{
FT_Bytes p = table;
GXV_morx_subtable_type1_StateOptRec st_rec;
GXV_NAME_ENTER( "morx chain subtable type1 (Contextual Glyph Subst)" );
GXV_LIMIT_CHECK( GXV_MORX_SUBTABLE_TYPE1_HEADER_SIZE );
st_rec.substitutionTable_num_lookupTables = 0;
gxvalid->xstatetable.optdata =
&st_rec;
gxvalid->xstatetable.optdata_load_func =
gxv_morx_subtable_type1_substitutionTable_load;
gxvalid->xstatetable.subtable_setup_func =
gxv_morx_subtable_type1_subtable_setup;
gxvalid->xstatetable.entry_glyphoffset_fmt =
GXV_GLYPHOFFSET_ULONG;
gxvalid->xstatetable.entry_validate_func =
gxv_morx_subtable_type1_entry_validate;
gxv_XStateTable_validate( p, limit, gxvalid );
gxv_morx_subtable_type1_substitutionTable_validate(
table + st_rec.substitutionTable,
table + st_rec.substitutionTable + st_rec.substitutionTable_length,
gxvalid );
GXV_EXIT;
}
/* END */