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/****************************************************************************
*
* otvmod.c
*
* FreeType's OpenType validation module implementation (body).
*
* Copyright (C) 2004-2024 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 <freetype/tttables.h>
#include <freetype/tttags.h>
#include <freetype/ftotval.h>
#include <freetype/internal/ftobjs.h>
#include <freetype/internal/services/svotval.h>
#include "otvmod.h"
#include "otvalid.h"
#include "otvcommn.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 otvmodule
static FT_Error
otv_load_table( FT_Face face,
FT_Tag tag,
FT_Byte* volatile* table,
FT_ULong* table_len )
{
FT_Error error;
FT_Memory memory = FT_FACE_MEMORY( face );
error = FT_Load_Sfnt_Table( face, tag, 0, NULL, table_len );
if ( FT_ERR_EQ( error, Table_Missing ) )
return FT_Err_Ok;
if ( error )
goto Exit;
if ( FT_QALLOC( *table, *table_len ) )
goto Exit;
error = FT_Load_Sfnt_Table( face, tag, 0, *table, table_len );
Exit:
return error;
}
static FT_Error
otv_validate( FT_Face volatile face,
FT_UInt ot_flags,
FT_Bytes *ot_base,
FT_Bytes *ot_gdef,
FT_Bytes *ot_gpos,
FT_Bytes *ot_gsub,
FT_Bytes *ot_jstf )
{
FT_Error error = FT_Err_Ok;
FT_Byte* volatile base;
FT_Byte* volatile gdef;
FT_Byte* volatile gpos;
FT_Byte* volatile gsub;
FT_Byte* volatile jstf;
FT_Byte* volatile math;
FT_ULong len_base, len_gdef, len_gpos, len_gsub, len_jstf;
FT_ULong len_math;
FT_UInt num_glyphs = (FT_UInt)face->num_glyphs;
FT_ValidatorRec volatile valid;
base = gdef = gpos = gsub = jstf = math = NULL;
len_base = len_gdef = len_gpos = len_gsub = len_jstf = len_math = 0;
/*
* XXX: OpenType tables cannot handle 32-bit glyph index,
* although broken TrueType can have 32-bit glyph index.
*/
if ( face->num_glyphs > 0xFFFFL )
{
FT_TRACE1(( "otv_validate: Invalid glyphs index (0x0000FFFF - 0x%08lx) ",
face->num_glyphs ));
FT_TRACE1(( "are not handled by OpenType tables\n" ));
num_glyphs = 0xFFFF;
}
/* load tables */
if ( ot_flags & FT_VALIDATE_BASE )
{
error = otv_load_table( face, TTAG_BASE, &base, &len_base );
if ( error )
goto Exit;
}
if ( ot_flags & FT_VALIDATE_GDEF )
{
error = otv_load_table( face, TTAG_GDEF, &gdef, &len_gdef );
if ( error )
goto Exit;
}
if ( ot_flags & FT_VALIDATE_GPOS )
{
error = otv_load_table( face, TTAG_GPOS, &gpos, &len_gpos );
if ( error )
goto Exit;
}
if ( ot_flags & FT_VALIDATE_GSUB )
{
error = otv_load_table( face, TTAG_GSUB, &gsub, &len_gsub );
if ( error )
goto Exit;
}
if ( ot_flags & FT_VALIDATE_JSTF )
{
error = otv_load_table( face, TTAG_JSTF, &jstf, &len_jstf );
if ( error )
goto Exit;
}
if ( ot_flags & FT_VALIDATE_MATH )
{
error = otv_load_table( face, TTAG_MATH, &math, &len_math );
if ( error )
goto Exit;
}
/* validate tables */
if ( base )
{
ft_validator_init( &valid, base, base + len_base, FT_VALIDATE_DEFAULT );
if ( ft_setjmp( valid.jump_buffer ) == 0 )
otv_BASE_validate( base, &valid );
error = valid.error;
if ( error )
goto Exit;
}
if ( gpos )
{
ft_validator_init( &valid, gpos, gpos + len_gpos, FT_VALIDATE_DEFAULT );
if ( ft_setjmp( valid.jump_buffer ) == 0 )
otv_GPOS_validate( gpos, num_glyphs, &valid );
error = valid.error;
if ( error )
goto Exit;
}
if ( gsub )
{
ft_validator_init( &valid, gsub, gsub + len_gsub, FT_VALIDATE_DEFAULT );
if ( ft_setjmp( valid.jump_buffer ) == 0 )
otv_GSUB_validate( gsub, num_glyphs, &valid );
error = valid.error;
if ( error )
goto Exit;
}
if ( gdef )
{
ft_validator_init( &valid, gdef, gdef + len_gdef, FT_VALIDATE_DEFAULT );
if ( ft_setjmp( valid.jump_buffer ) == 0 )
otv_GDEF_validate( gdef, gsub, gpos, num_glyphs, &valid );
error = valid.error;
if ( error )
goto Exit;
}
if ( jstf )
{
ft_validator_init( &valid, jstf, jstf + len_jstf, FT_VALIDATE_DEFAULT );
if ( ft_setjmp( valid.jump_buffer ) == 0 )
otv_JSTF_validate( jstf, gsub, gpos, num_glyphs, &valid );
error = valid.error;
if ( error )
goto Exit;
}
if ( math )
{
ft_validator_init( &valid, math, math + len_math, FT_VALIDATE_DEFAULT );
if ( ft_setjmp( valid.jump_buffer ) == 0 )
otv_MATH_validate( math, num_glyphs, &valid );
error = valid.error;
if ( error )
goto Exit;
}
*ot_base = (FT_Bytes)base;
*ot_gdef = (FT_Bytes)gdef;
*ot_gpos = (FT_Bytes)gpos;
*ot_gsub = (FT_Bytes)gsub;
*ot_jstf = (FT_Bytes)jstf;
Exit:
if ( error )
{
FT_Memory memory = FT_FACE_MEMORY( face );
FT_FREE( base );
FT_FREE( gdef );
FT_FREE( gpos );
FT_FREE( gsub );
FT_FREE( jstf );
}
{
FT_Memory memory = FT_FACE_MEMORY( face );
FT_FREE( math ); /* Can't return this as API is frozen */
}
return error;
}
static
const FT_Service_OTvalidateRec otvalid_interface =
{
otv_validate /* validate */
};
static
const FT_ServiceDescRec otvalid_services[] =
{
{ FT_SERVICE_ID_OPENTYPE_VALIDATE, &otvalid_interface },
{ NULL, NULL }
};
static FT_Pointer
otvalid_get_service( FT_Module module,
const char* service_id )
{
FT_UNUSED( module );
return ft_service_list_lookup( otvalid_services, service_id );
}
FT_CALLBACK_TABLE_DEF
const FT_Module_Class otv_module_class =
{
0,
sizeof ( FT_ModuleRec ),
"otvalid",
0x10000L,
0x20000L,
NULL, /* module-specific interface */
(FT_Module_Constructor)NULL, /* module_init */
(FT_Module_Destructor) NULL, /* module_done */
(FT_Module_Requester) otvalid_get_service /* get_interface */
};
/* END */