/***************************************************************************/ | |
/* */ | |
/* ftpatent.c */ | |
/* */ | |
/* FreeType API for checking patented TrueType bytecode instructions */ | |
/* (body). */ | |
/* */ | |
/* Copyright 2007-2015 by */ | |
/* David Turner. */ | |
/* */ | |
/* 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 <ft2build.h> | |
#include FT_FREETYPE_H | |
#include FT_TRUETYPE_TAGS_H | |
#include FT_INTERNAL_OBJECTS_H | |
#include FT_INTERNAL_STREAM_H | |
#include FT_SERVICE_SFNT_H | |
#include FT_SERVICE_TRUETYPE_GLYF_H | |
static FT_Bool | |
_tt_check_patents_in_range( FT_Stream stream, | |
FT_ULong size ) | |
{ | |
FT_Bool result = FALSE; | |
FT_Error error; | |
FT_Bytes p, end; | |
if ( FT_FRAME_ENTER( size ) ) | |
return 0; | |
p = stream->cursor; | |
end = p + size; | |
while ( p < end ) | |
{ | |
switch (p[0]) | |
{ | |
case 0x06: /* SPvTL // */ | |
case 0x07: /* SPvTL + */ | |
case 0x08: /* SFvTL // */ | |
case 0x09: /* SFvTL + */ | |
case 0x0A: /* SPvFS */ | |
case 0x0B: /* SFvFS */ | |
result = TRUE; | |
goto Exit; | |
case 0x40: | |
if ( p + 1 >= end ) | |
goto Exit; | |
p += p[1] + 2; | |
break; | |
case 0x41: | |
if ( p + 1 >= end ) | |
goto Exit; | |
p += p[1] * 2 + 2; | |
break; | |
case 0x71: /* DELTAP2 */ | |
case 0x72: /* DELTAP3 */ | |
case 0x73: /* DELTAC0 */ | |
case 0x74: /* DELTAC1 */ | |
case 0x75: /* DELTAC2 */ | |
result = TRUE; | |
goto Exit; | |
case 0xB0: | |
case 0xB1: | |
case 0xB2: | |
case 0xB3: | |
case 0xB4: | |
case 0xB5: | |
case 0xB6: | |
case 0xB7: | |
p += ( p[0] - 0xB0 ) + 2; | |
break; | |
case 0xB8: | |
case 0xB9: | |
case 0xBA: | |
case 0xBB: | |
case 0xBC: | |
case 0xBD: | |
case 0xBE: | |
case 0xBF: | |
p += ( p[0] - 0xB8 ) * 2 + 3; | |
break; | |
default: | |
p += 1; | |
break; | |
} | |
} | |
Exit: | |
FT_UNUSED( error ); | |
FT_FRAME_EXIT(); | |
return result; | |
} | |
static FT_Bool | |
_tt_check_patents_in_table( FT_Face face, | |
FT_ULong tag ) | |
{ | |
FT_Stream stream = face->stream; | |
FT_Error error = FT_Err_Ok; | |
FT_Service_SFNT_Table service; | |
FT_Bool result = FALSE; | |
FT_FACE_FIND_SERVICE( face, service, SFNT_TABLE ); | |
if ( service ) | |
{ | |
FT_UInt i = 0; | |
FT_ULong tag_i = 0, offset_i = 0, length_i = 0; | |
for ( i = 0; !error && tag_i != tag ; i++ ) | |
error = service->table_info( face, i, | |
&tag_i, &offset_i, &length_i ); | |
if ( error || | |
FT_STREAM_SEEK( offset_i ) ) | |
goto Exit; | |
result = _tt_check_patents_in_range( stream, length_i ); | |
} | |
Exit: | |
return result; | |
} | |
static FT_Bool | |
_tt_face_check_patents( FT_Face face ) | |
{ | |
FT_Stream stream = face->stream; | |
FT_UInt gindex; | |
FT_Error error; | |
FT_Bool result; | |
FT_Service_TTGlyf service; | |
result = _tt_check_patents_in_table( face, TTAG_fpgm ); | |
if ( result ) | |
goto Exit; | |
result = _tt_check_patents_in_table( face, TTAG_prep ); | |
if ( result ) | |
goto Exit; | |
FT_FACE_FIND_SERVICE( face, service, TT_GLYF ); | |
if ( service == NULL ) | |
goto Exit; | |
for ( gindex = 0; gindex < (FT_UInt)face->num_glyphs; gindex++ ) | |
{ | |
FT_ULong offset, num_ins, size; | |
FT_Int num_contours; | |
offset = service->get_location( face, gindex, &size ); | |
if ( size == 0 ) | |
continue; | |
if ( FT_STREAM_SEEK( offset ) || | |
FT_READ_SHORT( num_contours ) ) | |
continue; | |
if ( num_contours >= 0 ) /* simple glyph */ | |
{ | |
if ( FT_STREAM_SKIP( 8 + num_contours * 2 ) ) | |
continue; | |
} | |
else /* compound glyph */ | |
{ | |
FT_Bool has_instr = 0; | |
if ( FT_STREAM_SKIP( 8 ) ) | |
continue; | |
/* now read each component */ | |
for (;;) | |
{ | |
FT_UInt flags, toskip; | |
if( FT_READ_USHORT( flags ) ) | |
break; | |
toskip = 2 + 1 + 1; | |
if ( ( flags & ( 1 << 0 ) ) != 0 ) /* ARGS_ARE_WORDS */ | |
toskip += 2; | |
if ( ( flags & ( 1 << 3 ) ) != 0 ) /* WE_HAVE_A_SCALE */ | |
toskip += 2; | |
else if ( ( flags & ( 1 << 6 ) ) != 0 ) /* WE_HAVE_X_Y_SCALE */ | |
toskip += 4; | |
else if ( ( flags & ( 1 << 7 ) ) != 0 ) /* WE_HAVE_A_2x2 */ | |
toskip += 8; | |
if ( ( flags & ( 1 << 8 ) ) != 0 ) /* WE_HAVE_INSTRUCTIONS */ | |
has_instr = 1; | |
if ( FT_STREAM_SKIP( toskip ) ) | |
goto NextGlyph; | |
if ( ( flags & ( 1 << 5 ) ) == 0 ) /* MORE_COMPONENTS */ | |
break; | |
} | |
if ( !has_instr ) | |
goto NextGlyph; | |
} | |
if ( FT_READ_USHORT( num_ins ) ) | |
continue; | |
result = _tt_check_patents_in_range( stream, num_ins ); | |
if ( result ) | |
goto Exit; | |
NextGlyph: | |
; | |
} | |
Exit: | |
return result; | |
} | |
/* documentation is in freetype.h */ | |
FT_EXPORT_DEF( FT_Bool ) | |
FT_Face_CheckTrueTypePatents( FT_Face face ) | |
{ | |
FT_Bool result = FALSE; | |
if ( face && FT_IS_SFNT( face ) ) | |
result = _tt_face_check_patents( face ); | |
return result; | |
} | |
/* documentation is in freetype.h */ | |
FT_EXPORT_DEF( FT_Bool ) | |
FT_Face_SetUnpatentedHinting( FT_Face face, | |
FT_Bool value ) | |
{ | |
FT_Bool result = FALSE; | |
#if defined( TT_CONFIG_OPTION_UNPATENTED_HINTING ) && \ | |
!defined( TT_CONFIG_OPTION_BYTECODE_INTERPRETER ) | |
if ( face && FT_IS_SFNT( face ) ) | |
{ | |
result = !face->internal->ignore_unpatented_hinter; | |
face->internal->ignore_unpatented_hinter = !value; | |
} | |
#else | |
FT_UNUSED( face ); | |
FT_UNUSED( value ); | |
#endif | |
return result; | |
} | |
/* END */ |