/***************************************************************************/ | |
/* */ | |
/* gxvprop.c */ | |
/* */ | |
/* TrueTypeGX/AAT prop table validation (body). */ | |
/* */ | |
/* Copyright 2004-2015 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 "gxvalid.h" | |
#include "gxvcommn.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_gxvprop | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/***** *****/ | |
/***** Data and Types *****/ | |
/***** *****/ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
#define GXV_PROP_HEADER_SIZE ( 4 + 2 + 2 ) | |
#define GXV_PROP_SIZE_MIN GXV_PROP_HEADER_SIZE | |
typedef struct GXV_prop_DataRec_ | |
{ | |
FT_Fixed version; | |
} GXV_prop_DataRec, *GXV_prop_Data; | |
#define GXV_PROP_DATA( field ) GXV_TABLE_DATA( prop, field ) | |
#define GXV_PROP_FLOATER 0x8000U | |
#define GXV_PROP_USE_COMPLEMENTARY_BRACKET 0x1000U | |
#define GXV_PROP_COMPLEMENTARY_BRACKET_OFFSET 0x0F00U | |
#define GXV_PROP_ATTACHING_TO_RIGHT 0x0080U | |
#define GXV_PROP_RESERVED 0x0060U | |
#define GXV_PROP_DIRECTIONALITY_CLASS 0x001FU | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/***** *****/ | |
/***** UTILITY FUNCTIONS *****/ | |
/***** *****/ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
static void | |
gxv_prop_zero_advance_validate( FT_UShort gid, | |
GXV_Validator gxvalid ) | |
{ | |
FT_Face face; | |
FT_Error error; | |
FT_GlyphSlot glyph; | |
GXV_NAME_ENTER( "zero advance" ); | |
face = gxvalid->face; | |
error = FT_Load_Glyph( face, | |
gid, | |
FT_LOAD_IGNORE_TRANSFORM ); | |
if ( error ) | |
FT_INVALID_GLYPH_ID; | |
glyph = face->glyph; | |
if ( glyph->advance.x != (FT_Pos)0 || | |
glyph->advance.y != (FT_Pos)0 ) | |
{ | |
GXV_TRACE(( " found non-zero advance in zero-advance glyph\n" )); | |
FT_INVALID_DATA; | |
} | |
GXV_EXIT; | |
} | |
/* Pass 0 as GLYPH to check the default property */ | |
static void | |
gxv_prop_property_validate( FT_UShort property, | |
FT_UShort glyph, | |
GXV_Validator gxvalid ) | |
{ | |
if ( glyph != 0 && ( property & GXV_PROP_FLOATER ) ) | |
gxv_prop_zero_advance_validate( glyph, gxvalid ); | |
if ( property & GXV_PROP_USE_COMPLEMENTARY_BRACKET ) | |
{ | |
FT_UShort offset; | |
char complement; | |
offset = (FT_UShort)( property & GXV_PROP_COMPLEMENTARY_BRACKET_OFFSET ); | |
if ( offset == 0 ) | |
{ | |
GXV_TRACE(( " found zero offset to property\n" )); | |
FT_INVALID_OFFSET; | |
} | |
complement = (char)( offset >> 8 ); | |
if ( complement & 0x08 ) | |
{ | |
/* Top bit is set: negative */ | |
/* Calculate the absolute offset */ | |
complement = (char)( ( complement & 0x07 ) + 1 ); | |
/* The gid for complement must be greater than 0 */ | |
if ( glyph <= complement ) | |
{ | |
GXV_TRACE(( " found non-positive glyph complement\n" )); | |
FT_INVALID_DATA; | |
} | |
} | |
else | |
{ | |
/* The gid for complement must be the face. */ | |
gxv_glyphid_validate( (FT_UShort)( glyph + complement ), gxvalid ); | |
} | |
} | |
else | |
{ | |
if ( property & GXV_PROP_COMPLEMENTARY_BRACKET_OFFSET ) | |
GXV_TRACE(( "glyph %d cannot have complementary bracketing\n", | |
glyph )); | |
} | |
/* this is introduced in version 2.0 */ | |
if ( property & GXV_PROP_ATTACHING_TO_RIGHT ) | |
{ | |
if ( GXV_PROP_DATA( version ) == 0x00010000UL ) | |
{ | |
GXV_TRACE(( " found older version (1.0) in new version table\n" )); | |
FT_INVALID_DATA; | |
} | |
} | |
if ( property & GXV_PROP_RESERVED ) | |
{ | |
GXV_TRACE(( " found non-zero bits in reserved bits\n" )); | |
FT_INVALID_DATA; | |
} | |
if ( ( property & GXV_PROP_DIRECTIONALITY_CLASS ) > 11 ) | |
{ | |
/* TODO: Too restricted. Use the validation level. */ | |
if ( GXV_PROP_DATA( version ) == 0x00010000UL || | |
GXV_PROP_DATA( version ) == 0x00020000UL ) | |
{ | |
GXV_TRACE(( " found too old version in directionality class\n" )); | |
FT_INVALID_DATA; | |
} | |
} | |
} | |
static void | |
gxv_prop_LookupValue_validate( FT_UShort glyph, | |
GXV_LookupValueCPtr value_p, | |
GXV_Validator gxvalid ) | |
{ | |
gxv_prop_property_validate( value_p->u, glyph, gxvalid ); | |
} | |
/* | |
+===============+ --------+ | |
| lookup header | | | |
+===============+ | | |
| BinSrchHeader | | | |
+===============+ | | |
| lastGlyph[0] | | | |
+---------------+ | | |
| firstGlyph[0] | | head of lookup table | |
+---------------+ | + | |
| offset[0] | -> | offset [byte] | |
+===============+ | + | |
| lastGlyph[1] | | (glyphID - firstGlyph) * 2 [byte] | |
+---------------+ | | |
| firstGlyph[1] | | | |
+---------------+ | | |
| offset[1] | | | |
+===============+ | | |
| | |
... | | |
| | |
16bit value array | | |
+===============+ | | |
| value | <-------+ | |
... | |
*/ | |
static GXV_LookupValueDesc | |
gxv_prop_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; | |
} | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/***** *****/ | |
/***** prop TABLE *****/ | |
/***** *****/ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
FT_LOCAL_DEF( void ) | |
gxv_prop_validate( FT_Bytes table, | |
FT_Face face, | |
FT_Validator ftvalid ) | |
{ | |
FT_Bytes p = table; | |
FT_Bytes limit = 0; | |
GXV_ValidatorRec gxvalidrec; | |
GXV_Validator gxvalid = &gxvalidrec; | |
GXV_prop_DataRec proprec; | |
GXV_prop_Data prop = &proprec; | |
FT_Fixed version; | |
FT_UShort format; | |
FT_UShort defaultProp; | |
gxvalid->root = ftvalid; | |
gxvalid->table_data = prop; | |
gxvalid->face = face; | |
FT_TRACE3(( "validating `prop' table\n" )); | |
GXV_INIT; | |
GXV_LIMIT_CHECK( 4 + 2 + 2 ); | |
version = FT_NEXT_LONG( p ); | |
format = FT_NEXT_USHORT( p ); | |
defaultProp = FT_NEXT_USHORT( p ); | |
GXV_TRACE(( " version 0x%08x\n", version )); | |
GXV_TRACE(( " format 0x%04x\n", format )); | |
GXV_TRACE(( " defaultProp 0x%04x\n", defaultProp )); | |
/* only versions 1.0, 2.0, 3.0 are defined (1996) */ | |
if ( version != 0x00010000UL && | |
version != 0x00020000UL && | |
version != 0x00030000UL ) | |
{ | |
GXV_TRACE(( " found unknown version\n" )); | |
FT_INVALID_FORMAT; | |
} | |
/* only formats 0x0000, 0x0001 are defined (1996) */ | |
if ( format > 1 ) | |
{ | |
GXV_TRACE(( " found unknown format\n" )); | |
FT_INVALID_FORMAT; | |
} | |
gxv_prop_property_validate( defaultProp, 0, gxvalid ); | |
if ( format == 0 ) | |
{ | |
FT_TRACE3(( "(format 0, no per-glyph properties, " | |
"remaining %d bytes are skipped)", limit - p )); | |
goto Exit; | |
} | |
/* format == 1 */ | |
GXV_PROP_DATA( version ) = version; | |
gxvalid->lookupval_sign = GXV_LOOKUPVALUE_UNSIGNED; | |
gxvalid->lookupval_func = gxv_prop_LookupValue_validate; | |
gxvalid->lookupfmt4_trans = gxv_prop_LookupFmt4_transit; | |
gxv_LookupTable_validate( p, limit, gxvalid ); | |
Exit: | |
FT_TRACE4(( "\n" )); | |
} | |
/* END */ |