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Diffstat (limited to 'src/gxvalid/gxvprop.c')
| -rw-r--r-- | src/gxvalid/gxvprop.c | 301 |
1 files changed, 301 insertions, 0 deletions
diff --git a/src/gxvalid/gxvprop.c b/src/gxvalid/gxvprop.c new file mode 100644 index 0000000..010eeda --- /dev/null +++ b/src/gxvalid/gxvprop.c @@ -0,0 +1,301 @@ +/***************************************************************************/ +/* */ +/* gxvprop.c */ +/* */ +/* TrueTypeGX/AAT prop table validation (body). */ +/* */ +/* Copyright 2004, 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 "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 valid ) + { + FT_Face face; + FT_Error error; + FT_GlyphSlot glyph; + + + GXV_NAME_ENTER( "zero advance" ); + + face = valid->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 ) + 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 valid ) + { + if ( glyph != 0 && ( property & GXV_PROP_FLOATER ) ) + gxv_prop_zero_advance_validate( glyph, valid ); + + if ( property & GXV_PROP_USE_COMPLEMENTARY_BRACKET ) + { + FT_UShort offset; + char complement; + + + offset = (FT_UShort)( property & GXV_PROP_COMPLEMENTARY_BRACKET_OFFSET ); + if ( offset == 0 ) + FT_INVALID_DATA; + + 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 ) + FT_INVALID_DATA; + } + else + { + /* The gid for complement must be the face. */ + gxv_glyphid_validate( (FT_UShort)( glyph + complement ), valid ); + } + } + 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 ) + FT_INVALID_DATA; + } + + if ( property & GXV_PROP_RESERVED ) + 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 ) + FT_INVALID_DATA; + } + } + + + static void + gxv_prop_LookupValue_validate( FT_UShort glyph, + GXV_LookupValueDesc value, + GXV_Validator valid ) + { + gxv_prop_property_validate( value.u, glyph, valid ); + } + + + /* + +===============+ --------+ + | 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_LookupValueDesc base_value, + FT_Bytes lookuptbl_limit, + GXV_Validator valid ) + { + FT_Bytes p; + FT_Bytes limit; + FT_UShort offset; + GXV_LookupValueDesc value; + + /* XXX: check range? */ + offset = (FT_UShort)( base_value.u + + relative_gindex * sizeof( FT_UShort ) ); + p = valid->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 validrec; + GXV_Validator valid = &validrec; + + GXV_prop_DataRec proprec; + GXV_prop_Data prop = &proprec; + + FT_Fixed version; + FT_UShort format; + FT_UShort defaultProp; + + + valid->root = ftvalid; + valid->table_data = prop; + valid->face = face; + + FT_TRACE3(( "validating `prop' table\n" )); + GXV_INIT; + + GXV_LIMIT_CHECK( 4 + 2 + 2 ); + version = FT_NEXT_ULONG( p ); + format = FT_NEXT_USHORT( p ); + defaultProp = FT_NEXT_USHORT( p ); + + /* only versions 1.0, 2.0, 3.0 are defined (1996) */ + if ( version != 0x00010000UL && + version != 0x00020000UL && + version != 0x00030000UL ) + FT_INVALID_FORMAT; + + + /* only formats 0x0000, 0x0001 are defined (1996) */ + if ( format > 1 ) + FT_INVALID_FORMAT; + + gxv_prop_property_validate( defaultProp, 0, valid ); + + 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; + + valid->lookupval_sign = GXV_LOOKUPVALUE_UNSIGNED; + valid->lookupval_func = gxv_prop_LookupValue_validate; + valid->lookupfmt4_trans = gxv_prop_LookupFmt4_transit; + + gxv_LookupTable_validate( p, limit, valid ); + + Exit: + FT_TRACE4(( "\n" )); + } + + +/* END */ |