/***************************************************************************/
/* */
/* gxvmort2.c */
/* */
/* TrueTypeGX/AAT mort table validation */
/* body for type2 (Ligature Substitution) subtable. */
/* */
/* 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"
/*************************************************************************/
/* */
/* 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
typedef struct GXV_mort_subtable_type2_StateOptRec_
{
FT_UShort ligActionTable;
FT_UShort componentTable;
FT_UShort ligatureTable;
FT_UShort ligActionTable_length;
FT_UShort componentTable_length;
FT_UShort ligatureTable_length;
} GXV_mort_subtable_type2_StateOptRec,
*GXV_mort_subtable_type2_StateOptRecData;
#define GXV_MORT_SUBTABLE_TYPE2_HEADER_SIZE \
( GXV_STATETABLE_HEADER_SIZE + 2 + 2 + 2 )
static void
gxv_mort_subtable_type2_opttable_load( FT_Bytes table,
FT_Bytes limit,
GXV_Validator valid )
{
FT_Bytes p = table;
GXV_mort_subtable_type2_StateOptRecData optdata =
(GXV_mort_subtable_type2_StateOptRecData)valid->statetable.optdata;
GXV_LIMIT_CHECK( 2 + 2 + 2 );
optdata->ligActionTable = FT_NEXT_USHORT( p );
optdata->componentTable = FT_NEXT_USHORT( p );
optdata->ligatureTable = FT_NEXT_USHORT( p );
GXV_TRACE(( "offset to ligActionTable=0x%04x\n",
optdata->ligActionTable ));
GXV_TRACE(( "offset to componentTable=0x%04x\n",
optdata->componentTable ));
GXV_TRACE(( "offset to ligatureTable=0x%04x\n",
optdata->ligatureTable ));
}
static void
gxv_mort_subtable_type2_subtable_setup( FT_UShort table_size,
FT_UShort classTable,
FT_UShort stateArray,
FT_UShort entryTable,
FT_UShort *classTable_length_p,
FT_UShort *stateArray_length_p,
FT_UShort *entryTable_length_p,
GXV_Validator valid )
{
FT_UShort o[6];
FT_UShort *l[6];
FT_UShort buff[7];
GXV_mort_subtable_type2_StateOptRecData optdata =
(GXV_mort_subtable_type2_StateOptRecData)valid->statetable.optdata;
GXV_NAME_ENTER( "subtable boundaries setup" );
o[0] = classTable;
o[1] = stateArray;
o[2] = entryTable;
o[3] = optdata->ligActionTable;
o[4] = optdata->componentTable;
o[5] = optdata->ligatureTable;
l[0] = classTable_length_p;
l[1] = stateArray_length_p;
l[2] = entryTable_length_p;
l[3] = &(optdata->ligActionTable_length);
l[4] = &(optdata->componentTable_length);
l[5] = &(optdata->ligatureTable_length);
gxv_set_length_by_ushort_offset( o, l, buff, 6, table_size, valid );
GXV_TRACE(( "classTable: offset=0x%04x length=0x%04x\n",
classTable, *classTable_length_p ));
GXV_TRACE(( "stateArray: offset=0x%04x length=0x%04x\n",
stateArray, *stateArray_length_p ));
GXV_TRACE(( "entryTable: offset=0x%04x length=0x%04x\n",
entryTable, *entryTable_length_p ));
GXV_TRACE(( "ligActionTable: offset=0x%04x length=0x%04x\n",
optdata->ligActionTable,
optdata->ligActionTable_length ));
GXV_TRACE(( "componentTable: offset=0x%04x length=0x%04x\n",
optdata->componentTable,
optdata->componentTable_length ));
GXV_TRACE(( "ligatureTable: offset=0x%04x length=0x%04x\n",
optdata->ligatureTable,
optdata->ligatureTable_length ));
GXV_EXIT;
}
static void
gxv_mort_subtable_type2_ligActionOffset_validate(
FT_Bytes table,
FT_UShort ligActionOffset,
GXV_Validator valid )
{
/* access ligActionTable */
GXV_mort_subtable_type2_StateOptRecData optdata =
(GXV_mort_subtable_type2_StateOptRecData)valid->statetable.optdata;
FT_Bytes lat_base = table + optdata->ligActionTable;
FT_Bytes p = table + ligActionOffset;
FT_Bytes lat_limit = lat_base + optdata->ligActionTable;
GXV_32BIT_ALIGNMENT_VALIDATE( ligActionOffset );
if ( p < lat_base )
{
GXV_TRACE(( "too short offset 0x%04x: p < lat_base (%d byte rewind)\n",
ligActionOffset, lat_base - p ));
/* FontValidator, ftxvalidator, ftxdumperfuser warn but continue */
GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
}
else if ( lat_limit < p )
{
GXV_TRACE(( "too large offset 0x%04x: lat_limit < p (%d byte overrun)\n",
ligActionOffset, p - lat_limit ));
/* FontValidator, ftxvalidator, ftxdumperfuser warn but continue */
GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
}
else
{
/* validate entry in ligActionTable */
FT_ULong lig_action;
#ifdef GXV_LOAD_UNUSED_VARS
FT_UShort last;
FT_UShort store;
#endif
FT_ULong offset;
lig_action = FT_NEXT_ULONG( p );
#ifdef GXV_LOAD_UNUSED_VARS
last = (FT_UShort)( ( lig_action >> 31 ) & 1 );
store = (FT_UShort)( ( lig_action >> 30 ) & 1 );
#endif
/* Apple spec defines this offset as a word offset */
offset = lig_action & 0x3FFFFFFFUL;
if ( offset * 2 < optdata->ligatureTable )
{
GXV_TRACE(( "too short offset 0x%08x:"
" 2 x offset < ligatureTable (%d byte rewind)\n",
offset, optdata->ligatureTable - offset * 2 ));
GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
} else if ( offset * 2 >
optdata->ligatureTable + optdata->ligatureTable_length )
{
GXV_TRACE(( "too long offset 0x%08x:"
" 2 x offset > ligatureTable + ligatureTable_length"
" (%d byte overrun)\n",
offset,
optdata->ligatureTable + optdata->ligatureTable_length
- offset * 2 ));
GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
}
}
}
static void
gxv_mort_subtable_type2_entry_validate(
FT_Byte state,
FT_UShort flags,
GXV_StateTable_GlyphOffsetCPtr glyphOffset_p,
FT_Bytes table,
FT_Bytes limit,
GXV_Validator valid )
{
#ifdef GXV_LOAD_UNUSED_VARS
FT_UShort setComponent;
FT_UShort dontAdvance;
#endif
FT_UShort offset;
FT_UNUSED( state );
FT_UNUSED( glyphOffset_p );
FT_UNUSED( limit );
#ifdef GXV_LOAD_UNUSED_VARS
setComponent = (FT_UShort)( ( flags >> 15 ) & 1 );
dontAdvance = (FT_UShort)( ( flags >> 14 ) & 1 );
#endif
offset = (FT_UShort)( flags & 0x3FFFU );
if ( 0 < offset )
gxv_mort_subtable_type2_ligActionOffset_validate( table, offset,
valid );
}
static void
gxv_mort_subtable_type2_ligatureTable_validate( FT_Bytes table,
GXV_Validator valid )
{
GXV_mort_subtable_type2_StateOptRecData optdata =
(GXV_mort_subtable_type2_StateOptRecData)valid->statetable.optdata;
FT_Bytes p = table + optdata->ligatureTable;
FT_Bytes limit = table + optdata->ligatureTable
+ optdata->ligatureTable_length;
GXV_NAME_ENTER( "mort chain subtable type2 - substitutionTable" );
if ( 0 != optdata->ligatureTable )
{
/* Apple does not give specification of ligatureTable format */
while ( p < limit )
{
FT_UShort lig_gid;
GXV_LIMIT_CHECK( 2 );
lig_gid = FT_NEXT_USHORT( p );
if ( valid->face->num_glyphs < lig_gid )
GXV_SET_ERR_IF_PARANOID( FT_INVALID_GLYPH_ID );
}
}
GXV_EXIT;
}
FT_LOCAL_DEF( void )
gxv_mort_subtable_type2_validate( FT_Bytes table,
FT_Bytes limit,
GXV_Validator valid )
{
FT_Bytes p = table;
GXV_mort_subtable_type2_StateOptRec lig_rec;
GXV_NAME_ENTER( "mort chain subtable type2 (Ligature Substitution)" );
GXV_LIMIT_CHECK( GXV_MORT_SUBTABLE_TYPE2_HEADER_SIZE );
valid->statetable.optdata =
&lig_rec;
valid->statetable.optdata_load_func =
gxv_mort_subtable_type2_opttable_load;
valid->statetable.subtable_setup_func =
gxv_mort_subtable_type2_subtable_setup;
valid->statetable.entry_glyphoffset_fmt =
GXV_GLYPHOFFSET_NONE;
valid->statetable.entry_validate_func =
gxv_mort_subtable_type2_entry_validate;
gxv_StateTable_validate( p, limit, valid );
p += valid->subtable_length;
gxv_mort_subtable_type2_ligatureTable_validate( table, valid );
valid->subtable_length = p - table;
GXV_EXIT;
}
/* END */