/***************************************************************************/
/* */
/* gxvmort.c */
/* */
/* TrueTypeGX/AAT mort table validation (body). */
/* */
/* Copyright 2005 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 "gxvmort.h"
#include "gxvfeat.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_gxvmort
static void
gxv_mort_feature_validate( GXV_mort_feature f,
GXV_Validator valid )
{
if ( f->featureType >= gxv_feat_registry_length )
{
GXV_TRACE(( "featureType %d is out of registered range, "
"setting %d is unchecked\n",
f->featureType, f->featureSetting ));
if ( valid->root->level >= FT_VALIDATE_PARANOID )
FT_INVALID_DATA;
}
else if ( !gxv_feat_registry[f->featureType].existence )
{
GXV_TRACE(( "featureType %d is within registered area "
"but undefined, setting %d is unchecked\n",
f->featureType, f->featureSetting ));
if ( valid->root->level >= FT_VALIDATE_PARANOID )
FT_INVALID_DATA;
}
else
{
FT_Byte nSettings_max;
/* nSettings in gxvfeat.c is halved for exclusive on/off settings */
nSettings_max = gxv_feat_registry[f->featureType].nSettings;
if ( gxv_feat_registry[f->featureType].exclusive )
nSettings_max = (FT_Byte)( 2 * nSettings_max );
GXV_TRACE(( "featureType %d is registered", f->featureType ));
GXV_TRACE(( "setting %d", f->featureSetting ));
if ( f->featureSetting > nSettings_max )
{
GXV_TRACE(( "out of defined range %d", nSettings_max ));
if ( valid->root->level >= FT_VALIDATE_PARANOID )
FT_INVALID_DATA;
}
GXV_TRACE(( "\n" ));
}
/* TODO: enableFlags must be unique value in specified chain? */
}
/*
* nFeatureFlags is typed to FT_ULong to accept that in
* mort (typed FT_UShort) and morx (typed FT_ULong).
*/
FT_LOCAL_DEF( void )
gxv_mort_featurearray_validate( FT_Bytes table,
FT_Bytes limit,
FT_ULong nFeatureFlags,
GXV_Validator valid )
{
FT_Bytes p = table;
FT_ULong i;
GXV_mort_featureRec f = GXV_MORT_FEATURE_OFF;
GXV_NAME_ENTER( "mort feature list" );
for ( i = 0; i < nFeatureFlags; i++ )
{
GXV_LIMIT_CHECK( 2 + 2 + 4 + 4 );
f.featureType = FT_NEXT_USHORT( p );
f.featureSetting = FT_NEXT_USHORT( p );
f.enableFlags = FT_NEXT_ULONG( p );
f.disableFlags = FT_NEXT_ULONG( p );
gxv_mort_feature_validate( &f, valid );
}
if ( !IS_GXV_MORT_FEATURE_OFF( f ) )
FT_INVALID_DATA;
valid->subtable_length = p - table;
GXV_EXIT;
}
FT_LOCAL_DEF( void )
gxv_mort_coverage_validate( FT_UShort coverage,
GXV_Validator valid )
{
FT_UNUSED( valid );
if ( coverage & 0x8000U )
GXV_TRACE(( " this subtable is for vertical text only\n" ));
else
GXV_TRACE(( " this subtable is for horizontal text only\n" ));
if ( coverage & 0x4000 )
GXV_TRACE(( " this subtable is applied to glyph array "
"in descending order\n" ));
else
GXV_TRACE(( " this subtable is applied to glyph array "
"in ascending order\n" ));
if ( coverage & 0x2000 )
GXV_TRACE(( " this subtable is forcibly applied to "
"vertical/horizontal text\n" ));
if ( coverage & 0x1FF8 )
GXV_TRACE(( " coverage has non-zero bits in reserved area\n" ));
}
static void
gxv_mort_subtables_validate( FT_Bytes table,
FT_Bytes limit,
FT_UShort nSubtables,
GXV_Validator valid )
{
FT_Bytes p = table;
GXV_Validate_Func fmt_funcs_table[] =
{
gxv_mort_subtable_type0_validate, /* 0 */
gxv_mort_subtable_type1_validate, /* 1 */
gxv_mort_subtable_type2_validate, /* 2 */
NULL, /* 3 */
gxv_mort_subtable_type4_validate, /* 4 */
gxv_mort_subtable_type5_validate, /* 5 */
};
GXV_Validate_Func func;
FT_UShort i;
GXV_NAME_ENTER( "subtables in a chain" );
for ( i = 0; i < nSubtables; i++ )
{
FT_UShort length;
FT_UShort coverage;
FT_ULong subFeatureFlags;
FT_UInt type;
FT_UInt rest;
GXV_LIMIT_CHECK( 2 + 2 + 4 );
length = FT_NEXT_USHORT( p );
coverage = FT_NEXT_USHORT( p );
subFeatureFlags = FT_NEXT_ULONG( p );
GXV_TRACE(( "validating chain subtable %d/%d (%d bytes)\n",
i + 1, nSubtables, length ));
type = coverage & 0x0007;
rest = length - ( 2 + 2 + 4 );
GXV_LIMIT_CHECK( rest );
gxv_mort_coverage_validate( coverage, valid );
if ( type > 5 )
FT_INVALID_FORMAT;
func = fmt_funcs_table[type];
if ( func == NULL )
GXV_TRACE(( "morx type %d is reserved\n", type ));
func( p, p + rest, valid );
p += rest;
}
valid->subtable_length = p - table;
GXV_EXIT;
}
static void
gxv_mort_chain_validate( FT_Bytes table,
FT_Bytes limit,
GXV_Validator valid )
{
FT_Bytes p = table;
FT_ULong defaultFlags;
FT_ULong chainLength;
FT_UShort nFeatureFlags;
FT_UShort nSubtables;
GXV_NAME_ENTER( "mort chain header" );
GXV_LIMIT_CHECK( 4 + 4 + 2 + 2 );
defaultFlags = FT_NEXT_ULONG( p );
chainLength = FT_NEXT_ULONG( p );
nFeatureFlags = FT_NEXT_USHORT( p );
nSubtables = FT_NEXT_USHORT( p );
gxv_mort_featurearray_validate( p, table + chainLength,
nFeatureFlags, valid );
p += valid->subtable_length;
gxv_mort_subtables_validate( p, table + chainLength, nSubtables, valid );
valid->subtable_length = chainLength;
GXV_EXIT;
}
FT_LOCAL_DEF( void )
gxv_mort_validate( FT_Bytes table,
FT_Face face,
FT_Validator ftvalid )
{
GXV_ValidatorRec validrec;
GXV_Validator valid = &validrec;
FT_Bytes p = table;
FT_Bytes limit = 0;
FT_ULong version;
FT_ULong nChains;
FT_ULong i;
valid->root = ftvalid;
valid->face = face;
limit = valid->root->limit;
FT_TRACE3(( "validating `mort' table\n" ));
GXV_INIT;
GXV_LIMIT_CHECK( 4 + 4 );
version = FT_NEXT_ULONG( p );
nChains = FT_NEXT_ULONG( p );
if (version != 0x00010000UL)
FT_INVALID_FORMAT;
for ( i = 0; i < nChains; i++ )
{
GXV_TRACE(( "validating chain %d/%d\n", i + 1, nChains ));
GXV_32BIT_ALIGNMENT_VALIDATE( p - table );
gxv_mort_chain_validate( p, limit, valid );
p += valid->subtable_length;
}
FT_TRACE4(( "\n" ));
}
/* END */
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