1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
|
/***************************************************************************/
/* */
/* ftpatent.c */
/* */
/* FreeType API for checking patented TrueType bytecode instructions */
/* (body). */
/* */
/* Copyright 2007, 2008 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, length_i;
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_INTEPRETER )
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 */
|