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1 /***************************************************************************/
2 /*                                                                         */
3 /*  ttload.c                                                               */
4 /*                                                                         */
5 /*    Load the basic TrueType tables, i.e., tables that can be either in   */
6 /*    TTF or OTF fonts (body).                                             */
7 /*                                                                         */
8 /*  Copyright 1996-2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,   */
9 /*            2010 by                                                      */
10 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
11 /*                                                                         */
12 /*  This file is part of the FreeType project, and may only be used,       */
13 /*  modified, and distributed under the terms of the FreeType project      */
14 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
15 /*  this file you indicate that you have read the license and              */
16 /*  understand and accept it fully.                                        */
17 /*                                                                         */
18 /***************************************************************************/
19 
20 
21 #include <ft2build.h>
22 #include FT_INTERNAL_DEBUG_H
23 #include FT_INTERNAL_STREAM_H
24 #include FT_TRUETYPE_TAGS_H
25 #include "ttload.h"
26 
27 #include "sferrors.h"
28 
29 
30   /*************************************************************************/
31   /*                                                                       */
32   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
33   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
34   /* messages during execution.                                            */
35   /*                                                                       */
36 #undef  FT_COMPONENT
37 #define FT_COMPONENT  trace_ttload
38 
39 
40   /*************************************************************************/
41   /*                                                                       */
42   /* <Function>                                                            */
43   /*    tt_face_lookup_table                                               */
44   /*                                                                       */
45   /* <Description>                                                         */
46   /*    Looks for a TrueType table by name.                                */
47   /*                                                                       */
48   /* <Input>                                                               */
49   /*    face :: A face object handle.                                      */
50   /*                                                                       */
51   /*    tag  :: The searched tag.                                          */
52   /*                                                                       */
53   /* <Return>                                                              */
54   /*    A pointer to the table directory entry.  0 if not found.           */
55   /*                                                                       */
56   FT_LOCAL_DEF( TT_Table  )
tt_face_lookup_table(TT_Face face,FT_ULong tag)57   tt_face_lookup_table( TT_Face   face,
58                         FT_ULong  tag  )
59   {
60     TT_Table  entry;
61     TT_Table  limit;
62 #ifdef FT_DEBUG_LEVEL_TRACE
63     FT_Bool   zero_length = FALSE;
64 #endif
65 
66 
67     FT_TRACE4(( "tt_face_lookup_table: %08p, `%c%c%c%c' -- ",
68                 face,
69                 (FT_Char)( tag >> 24 ),
70                 (FT_Char)( tag >> 16 ),
71                 (FT_Char)( tag >> 8  ),
72                 (FT_Char)( tag       ) ));
73 
74     entry = face->dir_tables;
75     limit = entry + face->num_tables;
76 
77     for ( ; entry < limit; entry++ )
78     {
79       /* For compatibility with Windows, we consider    */
80       /* zero-length tables the same as missing tables. */
81       if ( entry->Tag == tag )
82       {
83         if ( entry->Length != 0 )
84         {
85           FT_TRACE4(( "found table.\n" ));
86           return entry;
87         }
88 #ifdef FT_DEBUG_LEVEL_TRACE
89         zero_length = TRUE;
90 #endif
91       }
92     }
93 
94 #ifdef FT_DEBUG_LEVEL_TRACE
95     if ( zero_length )
96       FT_TRACE4(( "ignoring empty table\n" ));
97     else
98       FT_TRACE4(( "could not find table\n" ));
99 #endif
100 
101     return NULL;
102   }
103 
104 
105   /*************************************************************************/
106   /*                                                                       */
107   /* <Function>                                                            */
108   /*    tt_face_goto_table                                                 */
109   /*                                                                       */
110   /* <Description>                                                         */
111   /*    Looks for a TrueType table by name, then seek a stream to it.      */
112   /*                                                                       */
113   /* <Input>                                                               */
114   /*    face   :: A face object handle.                                    */
115   /*                                                                       */
116   /*    tag    :: The searched tag.                                        */
117   /*                                                                       */
118   /*    stream :: The stream to seek when the table is found.              */
119   /*                                                                       */
120   /* <Output>                                                              */
121   /*    length :: The length of the table if found, undefined otherwise.   */
122   /*                                                                       */
123   /* <Return>                                                              */
124   /*    FreeType error code.  0 means success.                             */
125   /*                                                                       */
126   FT_LOCAL_DEF( FT_Error )
tt_face_goto_table(TT_Face face,FT_ULong tag,FT_Stream stream,FT_ULong * length)127   tt_face_goto_table( TT_Face    face,
128                       FT_ULong   tag,
129                       FT_Stream  stream,
130                       FT_ULong*  length )
131   {
132     TT_Table  table;
133     FT_Error  error;
134 
135 
136     table = tt_face_lookup_table( face, tag );
137     if ( table )
138     {
139       if ( length )
140         *length = table->Length;
141 
142       if ( FT_STREAM_SEEK( table->Offset ) )
143         goto Exit;
144     }
145     else
146       error = SFNT_Err_Table_Missing;
147 
148   Exit:
149     return error;
150   }
151 
152 
153   /* Here, we                                                         */
154   /*                                                                  */
155   /* - check that `num_tables' is valid (and adjust it if necessary)  */
156   /*                                                                  */
157   /* - look for a `head' table, check its size, and parse it to check */
158   /*   whether its `magic' field is correctly set                     */
159   /*                                                                  */
160   /* - errors (except errors returned by stream handling)             */
161   /*                                                                  */
162   /*     SFNT_Err_Unknown_File_Format:                                */
163   /*       no table is defined in directory, it is not sfnt-wrapped   */
164   /*       data                                                       */
165   /*     SFNT_Err_Table_Missing:                                      */
166   /*       table directory is valid, but essential tables             */
167   /*       (head/bhed/SING) are missing                               */
168   /*                                                                  */
169   static FT_Error
check_table_dir(SFNT_Header sfnt,FT_Stream stream)170   check_table_dir( SFNT_Header  sfnt,
171                    FT_Stream    stream )
172   {
173     FT_Error   error;
174     FT_UShort  nn, valid_entries = 0;
175     FT_UInt    has_head = 0, has_sing = 0, has_meta = 0;
176     FT_ULong   offset = sfnt->offset + 12;
177 
178     static const FT_Frame_Field  table_dir_entry_fields[] =
179     {
180 #undef  FT_STRUCTURE
181 #define FT_STRUCTURE  TT_TableRec
182 
183       FT_FRAME_START( 16 ),
184         FT_FRAME_ULONG( Tag ),
185         FT_FRAME_ULONG( CheckSum ),
186         FT_FRAME_ULONG( Offset ),
187         FT_FRAME_ULONG( Length ),
188       FT_FRAME_END
189     };
190 
191 
192     if ( FT_STREAM_SEEK( offset ) )
193       goto Exit;
194 
195     for ( nn = 0; nn < sfnt->num_tables; nn++ )
196     {
197       TT_TableRec  table;
198 
199 
200       if ( FT_STREAM_READ_FIELDS( table_dir_entry_fields, &table ) )
201       {
202         nn--;
203         FT_TRACE2(( "check_table_dir:"
204                     " can read only %d table%s in font (instead of %d)\n",
205                     nn, nn == 1 ? "" : "s", sfnt->num_tables ));
206         sfnt->num_tables = nn;
207         break;
208       }
209 
210       /* we ignore invalid tables */
211       if ( table.Offset + table.Length > stream->size )
212       {
213         FT_TRACE2(( "check_table_dir: table entry %d invalid\n", nn ));
214         continue;
215       }
216       else
217         valid_entries++;
218 
219       if ( table.Tag == TTAG_head || table.Tag == TTAG_bhed )
220       {
221         FT_UInt32  magic;
222 
223 
224 #ifndef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
225         if ( table.Tag == TTAG_head )
226 #endif
227           has_head = 1;
228 
229         /*
230          * The table length should be 0x36, but certain font tools make it
231          * 0x38, so we will just check that it is greater.
232          *
233          * Note that according to the specification, the table must be
234          * padded to 32-bit lengths, but this doesn't apply to the value of
235          * its `Length' field!
236          *
237          */
238         if ( table.Length < 0x36 )
239         {
240           FT_TRACE2(( "check_table_dir: `head' table too small\n" ));
241           error = SFNT_Err_Table_Missing;
242           goto Exit;
243         }
244 
245         if ( FT_STREAM_SEEK( table.Offset + 12 ) ||
246              FT_READ_ULONG( magic )              )
247           goto Exit;
248 
249         if ( magic != 0x5F0F3CF5UL )
250         {
251           FT_TRACE2(( "check_table_dir:"
252                       " no magic number found in `head' table\n"));
253           error = SFNT_Err_Table_Missing;
254           goto Exit;
255         }
256 
257         if ( FT_STREAM_SEEK( offset + ( nn + 1 ) * 16 ) )
258           goto Exit;
259       }
260       else if ( table.Tag == TTAG_SING )
261         has_sing = 1;
262       else if ( table.Tag == TTAG_META )
263         has_meta = 1;
264     }
265 
266     sfnt->num_tables = valid_entries;
267 
268     if ( sfnt->num_tables == 0 )
269     {
270       FT_TRACE2(( "check_table_dir: no tables found\n" ));
271       error = SFNT_Err_Unknown_File_Format;
272       goto Exit;
273     }
274 
275     /* if `sing' and `meta' tables are present, there is no `head' table */
276     if ( has_head || ( has_sing && has_meta ) )
277     {
278       error = SFNT_Err_Ok;
279       goto Exit;
280     }
281     else
282     {
283       FT_TRACE2(( "check_table_dir:" ));
284 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
285       FT_TRACE2(( " neither `head', `bhed', nor `sing' table found\n" ));
286 #else
287       FT_TRACE2(( " neither `head' nor `sing' table found\n" ));
288 #endif
289       error = SFNT_Err_Table_Missing;
290     }
291 
292   Exit:
293     return error;
294   }
295 
296 
297   /*************************************************************************/
298   /*                                                                       */
299   /* <Function>                                                            */
300   /*    tt_face_load_font_dir                                              */
301   /*                                                                       */
302   /* <Description>                                                         */
303   /*    Loads the header of a SFNT font file.                              */
304   /*                                                                       */
305   /* <Input>                                                               */
306   /*    face       :: A handle to the target face object.                  */
307   /*                                                                       */
308   /*    stream     :: The input stream.                                    */
309   /*                                                                       */
310   /* <Output>                                                              */
311   /*    sfnt       :: The SFNT header.                                     */
312   /*                                                                       */
313   /* <Return>                                                              */
314   /*    FreeType error code.  0 means success.                             */
315   /*                                                                       */
316   /* <Note>                                                                */
317   /*    The stream cursor must be at the beginning of the font directory.  */
318   /*                                                                       */
319   FT_LOCAL_DEF( FT_Error )
tt_face_load_font_dir(TT_Face face,FT_Stream stream)320   tt_face_load_font_dir( TT_Face    face,
321                          FT_Stream  stream )
322   {
323     SFNT_HeaderRec  sfnt;
324     FT_Error        error;
325     FT_Memory       memory = stream->memory;
326     TT_TableRec*    entry;
327     FT_Int          nn;
328 
329     static const FT_Frame_Field  offset_table_fields[] =
330     {
331 #undef  FT_STRUCTURE
332 #define FT_STRUCTURE  SFNT_HeaderRec
333 
334       FT_FRAME_START( 8 ),
335         FT_FRAME_USHORT( num_tables ),
336         FT_FRAME_USHORT( search_range ),
337         FT_FRAME_USHORT( entry_selector ),
338         FT_FRAME_USHORT( range_shift ),
339       FT_FRAME_END
340     };
341 
342 
343     FT_TRACE2(( "tt_face_load_font_dir: %08p\n", face ));
344 
345     /* read the offset table */
346 
347     sfnt.offset = FT_STREAM_POS();
348 
349     if ( FT_READ_ULONG( sfnt.format_tag )                    ||
350          FT_STREAM_READ_FIELDS( offset_table_fields, &sfnt ) )
351       goto Exit;
352 
353     /* many fonts don't have these fields set correctly */
354 #if 0
355     if ( sfnt.search_range != 1 << ( sfnt.entry_selector + 4 )        ||
356          sfnt.search_range + sfnt.range_shift != sfnt.num_tables << 4 )
357       return SFNT_Err_Unknown_File_Format;
358 #endif
359 
360     /* load the table directory */
361 
362     FT_TRACE2(( "-- Number of tables: %10u\n",    sfnt.num_tables ));
363     FT_TRACE2(( "-- Format version:   0x%08lx\n", sfnt.format_tag ));
364 
365     /* check first */
366     error = check_table_dir( &sfnt, stream );
367     if ( error )
368     {
369       FT_TRACE2(( "tt_face_load_font_dir:"
370                   " invalid table directory for TrueType\n" ));
371 
372       goto Exit;
373     }
374 
375     face->num_tables = sfnt.num_tables;
376     face->format_tag = sfnt.format_tag;
377 
378     if ( FT_QNEW_ARRAY( face->dir_tables, face->num_tables ) )
379       goto Exit;
380 
381     if ( FT_STREAM_SEEK( sfnt.offset + 12 )       ||
382          FT_FRAME_ENTER( face->num_tables * 16L ) )
383       goto Exit;
384 
385     entry = face->dir_tables;
386 
387     for ( nn = 0; nn < sfnt.num_tables; nn++ )
388     {
389       entry->Tag      = FT_GET_TAG4();
390       entry->CheckSum = FT_GET_ULONG();
391       entry->Offset   = FT_GET_LONG();
392       entry->Length   = FT_GET_LONG();
393 
394       /* ignore invalid tables */
395       if ( entry->Offset + entry->Length > stream->size )
396         continue;
397       else
398       {
399         FT_TRACE2(( "  %c%c%c%c  -  %08lx  -  %08lx\n",
400                     (FT_Char)( entry->Tag >> 24 ),
401                     (FT_Char)( entry->Tag >> 16 ),
402                     (FT_Char)( entry->Tag >> 8  ),
403                     (FT_Char)( entry->Tag       ),
404                     entry->Offset,
405                     entry->Length ));
406         entry++;
407       }
408     }
409 
410     FT_FRAME_EXIT();
411 
412     FT_TRACE2(( "table directory loaded\n\n" ));
413 
414   Exit:
415     return error;
416   }
417 
418 
419   /*************************************************************************/
420   /*                                                                       */
421   /* <Function>                                                            */
422   /*    tt_face_load_any                                                   */
423   /*                                                                       */
424   /* <Description>                                                         */
425   /*    Loads any font table into client memory.                           */
426   /*                                                                       */
427   /* <Input>                                                               */
428   /*    face   :: The face object to look for.                             */
429   /*                                                                       */
430   /*    tag    :: The tag of table to load.  Use the value 0 if you want   */
431   /*              to access the whole font file, else set this parameter   */
432   /*              to a valid TrueType table tag that you can forge with    */
433   /*              the MAKE_TT_TAG macro.                                   */
434   /*                                                                       */
435   /*    offset :: The starting offset in the table (or the file if         */
436   /*              tag == 0).                                               */
437   /*                                                                       */
438   /*    length :: The address of the decision variable:                    */
439   /*                                                                       */
440   /*                If length == NULL:                                     */
441   /*                  Loads the whole table.  Returns an error if          */
442   /*                  `offset' == 0!                                       */
443   /*                                                                       */
444   /*                If *length == 0:                                       */
445   /*                  Exits immediately; returning the length of the given */
446   /*                  table or of the font file, depending on the value of */
447   /*                  `tag'.                                               */
448   /*                                                                       */
449   /*                If *length != 0:                                       */
450   /*                  Loads the next `length' bytes of table or font,      */
451   /*                  starting at offset `offset' (in table or font too).  */
452   /*                                                                       */
453   /* <Output>                                                              */
454   /*    buffer :: The address of target buffer.                            */
455   /*                                                                       */
456   /* <Return>                                                              */
457   /*    FreeType error code.  0 means success.                             */
458   /*                                                                       */
459   FT_LOCAL_DEF( FT_Error )
tt_face_load_any(TT_Face face,FT_ULong tag,FT_Long offset,FT_Byte * buffer,FT_ULong * length)460   tt_face_load_any( TT_Face    face,
461                     FT_ULong   tag,
462                     FT_Long    offset,
463                     FT_Byte*   buffer,
464                     FT_ULong*  length )
465   {
466     FT_Error   error;
467     FT_Stream  stream;
468     TT_Table   table;
469     FT_ULong   size;
470 
471 
472     if ( tag != 0 )
473     {
474       /* look for tag in font directory */
475       table = tt_face_lookup_table( face, tag );
476       if ( !table )
477       {
478         error = SFNT_Err_Table_Missing;
479         goto Exit;
480       }
481 
482       offset += table->Offset;
483       size    = table->Length;
484     }
485     else
486       /* tag == 0 -- the user wants to access the font file directly */
487       size = face->root.stream->size;
488 
489     if ( length && *length == 0 )
490     {
491       *length = size;
492 
493       return SFNT_Err_Ok;
494     }
495 
496     if ( length )
497       size = *length;
498 
499     stream = face->root.stream;
500     /* the `if' is syntactic sugar for picky compilers */
501     if ( FT_STREAM_READ_AT( offset, buffer, size ) )
502       goto Exit;
503 
504   Exit:
505     return error;
506   }
507 
508 
509   /*************************************************************************/
510   /*                                                                       */
511   /* <Function>                                                            */
512   /*    tt_face_load_generic_header                                        */
513   /*                                                                       */
514   /* <Description>                                                         */
515   /*    Loads the TrueType table `head' or `bhed'.                         */
516   /*                                                                       */
517   /* <Input>                                                               */
518   /*    face   :: A handle to the target face object.                      */
519   /*                                                                       */
520   /*    stream :: The input stream.                                        */
521   /*                                                                       */
522   /* <Return>                                                              */
523   /*    FreeType error code.  0 means success.                             */
524   /*                                                                       */
525   static FT_Error
tt_face_load_generic_header(TT_Face face,FT_Stream stream,FT_ULong tag)526   tt_face_load_generic_header( TT_Face    face,
527                                FT_Stream  stream,
528                                FT_ULong   tag )
529   {
530     FT_Error    error;
531     TT_Header*  header;
532 
533     static const FT_Frame_Field  header_fields[] =
534     {
535 #undef  FT_STRUCTURE
536 #define FT_STRUCTURE  TT_Header
537 
538       FT_FRAME_START( 54 ),
539         FT_FRAME_ULONG ( Table_Version ),
540         FT_FRAME_ULONG ( Font_Revision ),
541         FT_FRAME_LONG  ( CheckSum_Adjust ),
542         FT_FRAME_LONG  ( Magic_Number ),
543         FT_FRAME_USHORT( Flags ),
544         FT_FRAME_USHORT( Units_Per_EM ),
545         FT_FRAME_LONG  ( Created[0] ),
546         FT_FRAME_LONG  ( Created[1] ),
547         FT_FRAME_LONG  ( Modified[0] ),
548         FT_FRAME_LONG  ( Modified[1] ),
549         FT_FRAME_SHORT ( xMin ),
550         FT_FRAME_SHORT ( yMin ),
551         FT_FRAME_SHORT ( xMax ),
552         FT_FRAME_SHORT ( yMax ),
553         FT_FRAME_USHORT( Mac_Style ),
554         FT_FRAME_USHORT( Lowest_Rec_PPEM ),
555         FT_FRAME_SHORT ( Font_Direction ),
556         FT_FRAME_SHORT ( Index_To_Loc_Format ),
557         FT_FRAME_SHORT ( Glyph_Data_Format ),
558       FT_FRAME_END
559     };
560 
561 
562     error = face->goto_table( face, tag, stream, 0 );
563     if ( error )
564       goto Exit;
565 
566     header = &face->header;
567 
568     if ( FT_STREAM_READ_FIELDS( header_fields, header ) )
569       goto Exit;
570 
571     FT_TRACE3(( "Units per EM: %4u\n", header->Units_Per_EM ));
572     FT_TRACE3(( "IndexToLoc:   %4d\n", header->Index_To_Loc_Format ));
573 
574   Exit:
575     return error;
576   }
577 
578 
579   FT_LOCAL_DEF( FT_Error )
tt_face_load_head(TT_Face face,FT_Stream stream)580   tt_face_load_head( TT_Face    face,
581                      FT_Stream  stream )
582   {
583     return tt_face_load_generic_header( face, stream, TTAG_head );
584   }
585 
586 
587 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
588 
589   FT_LOCAL_DEF( FT_Error )
tt_face_load_bhed(TT_Face face,FT_Stream stream)590   tt_face_load_bhed( TT_Face    face,
591                      FT_Stream  stream )
592   {
593     return tt_face_load_generic_header( face, stream, TTAG_bhed );
594   }
595 
596 #endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */
597 
598 
599   /*************************************************************************/
600   /*                                                                       */
601   /* <Function>                                                            */
602   /*    tt_face_load_max_profile                                           */
603   /*                                                                       */
604   /* <Description>                                                         */
605   /*    Loads the maximum profile into a face object.                      */
606   /*                                                                       */
607   /* <Input>                                                               */
608   /*    face   :: A handle to the target face object.                      */
609   /*                                                                       */
610   /*    stream :: The input stream.                                        */
611   /*                                                                       */
612   /* <Return>                                                              */
613   /*    FreeType error code.  0 means success.                             */
614   /*                                                                       */
615   FT_LOCAL_DEF( FT_Error )
tt_face_load_maxp(TT_Face face,FT_Stream stream)616   tt_face_load_maxp( TT_Face    face,
617                      FT_Stream  stream )
618   {
619     FT_Error        error;
620     TT_MaxProfile*  maxProfile = &face->max_profile;
621 
622     const FT_Frame_Field  maxp_fields[] =
623     {
624 #undef  FT_STRUCTURE
625 #define FT_STRUCTURE  TT_MaxProfile
626 
627       FT_FRAME_START( 6 ),
628         FT_FRAME_LONG  ( version ),
629         FT_FRAME_USHORT( numGlyphs ),
630       FT_FRAME_END
631     };
632 
633     const FT_Frame_Field  maxp_fields_extra[] =
634     {
635       FT_FRAME_START( 26 ),
636         FT_FRAME_USHORT( maxPoints ),
637         FT_FRAME_USHORT( maxContours ),
638         FT_FRAME_USHORT( maxCompositePoints ),
639         FT_FRAME_USHORT( maxCompositeContours ),
640         FT_FRAME_USHORT( maxZones ),
641         FT_FRAME_USHORT( maxTwilightPoints ),
642         FT_FRAME_USHORT( maxStorage ),
643         FT_FRAME_USHORT( maxFunctionDefs ),
644         FT_FRAME_USHORT( maxInstructionDefs ),
645         FT_FRAME_USHORT( maxStackElements ),
646         FT_FRAME_USHORT( maxSizeOfInstructions ),
647         FT_FRAME_USHORT( maxComponentElements ),
648         FT_FRAME_USHORT( maxComponentDepth ),
649       FT_FRAME_END
650     };
651 
652 
653     error = face->goto_table( face, TTAG_maxp, stream, 0 );
654     if ( error )
655       goto Exit;
656 
657     if ( FT_STREAM_READ_FIELDS( maxp_fields, maxProfile ) )
658       goto Exit;
659 
660     maxProfile->maxPoints             = 0;
661     maxProfile->maxContours           = 0;
662     maxProfile->maxCompositePoints    = 0;
663     maxProfile->maxCompositeContours  = 0;
664     maxProfile->maxZones              = 0;
665     maxProfile->maxTwilightPoints     = 0;
666     maxProfile->maxStorage            = 0;
667     maxProfile->maxFunctionDefs       = 0;
668     maxProfile->maxInstructionDefs    = 0;
669     maxProfile->maxStackElements      = 0;
670     maxProfile->maxSizeOfInstructions = 0;
671     maxProfile->maxComponentElements  = 0;
672     maxProfile->maxComponentDepth     = 0;
673 
674     if ( maxProfile->version >= 0x10000L )
675     {
676       if ( FT_STREAM_READ_FIELDS( maxp_fields_extra, maxProfile ) )
677         goto Exit;
678 
679       /* XXX: an adjustment that is necessary to load certain */
680       /*      broken fonts like `Keystrokes MT' :-(           */
681       /*                                                      */
682       /*   We allocate 64 function entries by default when    */
683       /*   the maxFunctionDefs field is null.                 */
684 
685       if ( maxProfile->maxFunctionDefs == 0 )
686         maxProfile->maxFunctionDefs = 64;
687 
688       /* we add 4 phantom points later */
689       if ( maxProfile->maxTwilightPoints > ( 0xFFFFU - 4 ) )
690       {
691         FT_TRACE0(( "tt_face_load_maxp:"
692                     " too much twilight points in `maxp' table;\n"
693                     "                  "
694                     " some glyphs might be rendered incorrectly\n" ));
695 
696         maxProfile->maxTwilightPoints = 0xFFFFU - 4;
697       }
698 
699       /* we arbitrarily limit recursion to avoid stack exhaustion */
700       if ( maxProfile->maxComponentDepth > 100 )
701       {
702         FT_TRACE0(( "tt_face_load_maxp:"
703                     " abnormally large component depth (%d) set to 100\n",
704                     maxProfile->maxComponentDepth ));
705         maxProfile->maxComponentDepth = 100;
706       }
707     }
708 
709     FT_TRACE3(( "numGlyphs: %u\n", maxProfile->numGlyphs ));
710 
711   Exit:
712     return error;
713   }
714 
715 
716   /*************************************************************************/
717   /*                                                                       */
718   /* <Function>                                                            */
719   /*    tt_face_load_names                                                 */
720   /*                                                                       */
721   /* <Description>                                                         */
722   /*    Loads the name records.                                            */
723   /*                                                                       */
724   /* <Input>                                                               */
725   /*    face   :: A handle to the target face object.                      */
726   /*                                                                       */
727   /*    stream :: The input stream.                                        */
728   /*                                                                       */
729   /* <Return>                                                              */
730   /*    FreeType error code.  0 means success.                             */
731   /*                                                                       */
732   FT_LOCAL_DEF( FT_Error )
tt_face_load_name(TT_Face face,FT_Stream stream)733   tt_face_load_name( TT_Face    face,
734                      FT_Stream  stream )
735   {
736     FT_Error      error;
737     FT_Memory     memory = stream->memory;
738     FT_ULong      table_pos, table_len;
739     FT_ULong      storage_start, storage_limit;
740     FT_UInt       count;
741     TT_NameTable  table;
742 
743     static const FT_Frame_Field  name_table_fields[] =
744     {
745 #undef  FT_STRUCTURE
746 #define FT_STRUCTURE  TT_NameTableRec
747 
748       FT_FRAME_START( 6 ),
749         FT_FRAME_USHORT( format ),
750         FT_FRAME_USHORT( numNameRecords ),
751         FT_FRAME_USHORT( storageOffset ),
752       FT_FRAME_END
753     };
754 
755     static const FT_Frame_Field  name_record_fields[] =
756     {
757 #undef  FT_STRUCTURE
758 #define FT_STRUCTURE  TT_NameEntryRec
759 
760       /* no FT_FRAME_START */
761         FT_FRAME_USHORT( platformID ),
762         FT_FRAME_USHORT( encodingID ),
763         FT_FRAME_USHORT( languageID ),
764         FT_FRAME_USHORT( nameID ),
765         FT_FRAME_USHORT( stringLength ),
766         FT_FRAME_USHORT( stringOffset ),
767       FT_FRAME_END
768     };
769 
770 
771     table         = &face->name_table;
772     table->stream = stream;
773 
774     error = face->goto_table( face, TTAG_name, stream, &table_len );
775     if ( error )
776       goto Exit;
777 
778     table_pos = FT_STREAM_POS();
779 
780 
781     if ( FT_STREAM_READ_FIELDS( name_table_fields, table ) )
782       goto Exit;
783 
784     /* Some popular Asian fonts have an invalid `storageOffset' value   */
785     /* (it should be at least "6 + 12*num_names").  However, the string */
786     /* offsets, computed as "storageOffset + entry->stringOffset", are  */
787     /* valid pointers within the name table...                          */
788     /*                                                                  */
789     /* We thus can't check `storageOffset' right now.                   */
790     /*                                                                  */
791     storage_start = table_pos + 6 + 12*table->numNameRecords;
792     storage_limit = table_pos + table_len;
793 
794     if ( storage_start > storage_limit )
795     {
796       FT_ERROR(( "tt_face_load_name: invalid `name' table\n" ));
797       error = SFNT_Err_Name_Table_Missing;
798       goto Exit;
799     }
800 
801     /* Allocate the array of name records. */
802     count                 = table->numNameRecords;
803     table->numNameRecords = 0;
804 
805     if ( FT_NEW_ARRAY( table->names, count ) ||
806          FT_FRAME_ENTER( count * 12 )        )
807       goto Exit;
808 
809     /* Load the name records and determine how much storage is needed */
810     /* to hold the strings themselves.                                */
811     {
812       TT_NameEntryRec*  entry = table->names;
813 
814 
815       for ( ; count > 0; count-- )
816       {
817         if ( FT_STREAM_READ_FIELDS( name_record_fields, entry ) )
818           continue;
819 
820         /* check that the name is not empty */
821         if ( entry->stringLength == 0 )
822           continue;
823 
824         /* check that the name string is within the table */
825         entry->stringOffset += table_pos + table->storageOffset;
826         if ( entry->stringOffset                       < storage_start ||
827              entry->stringOffset + entry->stringLength > storage_limit )
828         {
829           /* invalid entry - ignore it */
830           entry->stringOffset = 0;
831           entry->stringLength = 0;
832           continue;
833         }
834 
835         entry++;
836       }
837 
838       table->numNameRecords = (FT_UInt)( entry - table->names );
839     }
840 
841     FT_FRAME_EXIT();
842 
843     /* everything went well, update face->num_names */
844     face->num_names = (FT_UShort) table->numNameRecords;
845 
846   Exit:
847     return error;
848   }
849 
850 
851   /*************************************************************************/
852   /*                                                                       */
853   /* <Function>                                                            */
854   /*    tt_face_free_names                                                 */
855   /*                                                                       */
856   /* <Description>                                                         */
857   /*    Frees the name records.                                            */
858   /*                                                                       */
859   /* <Input>                                                               */
860   /*    face :: A handle to the target face object.                        */
861   /*                                                                       */
862   FT_LOCAL_DEF( void )
tt_face_free_name(TT_Face face)863   tt_face_free_name( TT_Face  face )
864   {
865     FT_Memory     memory = face->root.driver->root.memory;
866     TT_NameTable  table  = &face->name_table;
867     TT_NameEntry  entry  = table->names;
868     FT_UInt       count  = table->numNameRecords;
869 
870 
871     if ( table->names )
872     {
873       for ( ; count > 0; count--, entry++ )
874       {
875         FT_FREE( entry->string );
876         entry->stringLength = 0;
877       }
878 
879       /* free strings table */
880       FT_FREE( table->names );
881     }
882 
883     table->numNameRecords = 0;
884     table->format         = 0;
885     table->storageOffset  = 0;
886   }
887 
888 
889   /*************************************************************************/
890   /*                                                                       */
891   /* <Function>                                                            */
892   /*    tt_face_load_cmap                                                  */
893   /*                                                                       */
894   /* <Description>                                                         */
895   /*    Loads the cmap directory in a face object.  The cmaps themselves   */
896   /*    are loaded on demand in the `ttcmap.c' module.                     */
897   /*                                                                       */
898   /* <Input>                                                               */
899   /*    face   :: A handle to the target face object.                      */
900   /*                                                                       */
901   /*    stream :: A handle to the input stream.                            */
902   /*                                                                       */
903   /* <Return>                                                              */
904   /*    FreeType error code.  0 means success.                             */
905   /*                                                                       */
906 
907   FT_LOCAL_DEF( FT_Error )
tt_face_load_cmap(TT_Face face,FT_Stream stream)908   tt_face_load_cmap( TT_Face    face,
909                      FT_Stream  stream )
910   {
911     FT_Error  error;
912 
913 
914     error = face->goto_table( face, TTAG_cmap, stream, &face->cmap_size );
915     if ( error )
916       goto Exit;
917 
918     if ( FT_FRAME_EXTRACT( face->cmap_size, face->cmap_table ) )
919       face->cmap_size = 0;
920 
921   Exit:
922     return error;
923   }
924 
925 
926 
927   /*************************************************************************/
928   /*                                                                       */
929   /* <Function>                                                            */
930   /*    tt_face_load_os2                                                   */
931   /*                                                                       */
932   /* <Description>                                                         */
933   /*    Loads the OS2 table.                                               */
934   /*                                                                       */
935   /* <Input>                                                               */
936   /*    face   :: A handle to the target face object.                      */
937   /*                                                                       */
938   /*    stream :: A handle to the input stream.                            */
939   /*                                                                       */
940   /* <Return>                                                              */
941   /*    FreeType error code.  0 means success.                             */
942   /*                                                                       */
943   FT_LOCAL_DEF( FT_Error )
tt_face_load_os2(TT_Face face,FT_Stream stream)944   tt_face_load_os2( TT_Face    face,
945                     FT_Stream  stream )
946   {
947     FT_Error  error;
948     TT_OS2*   os2;
949 
950     const FT_Frame_Field  os2_fields[] =
951     {
952 #undef  FT_STRUCTURE
953 #define FT_STRUCTURE  TT_OS2
954 
955       FT_FRAME_START( 78 ),
956         FT_FRAME_USHORT( version ),
957         FT_FRAME_SHORT ( xAvgCharWidth ),
958         FT_FRAME_USHORT( usWeightClass ),
959         FT_FRAME_USHORT( usWidthClass ),
960         FT_FRAME_SHORT ( fsType ),
961         FT_FRAME_SHORT ( ySubscriptXSize ),
962         FT_FRAME_SHORT ( ySubscriptYSize ),
963         FT_FRAME_SHORT ( ySubscriptXOffset ),
964         FT_FRAME_SHORT ( ySubscriptYOffset ),
965         FT_FRAME_SHORT ( ySuperscriptXSize ),
966         FT_FRAME_SHORT ( ySuperscriptYSize ),
967         FT_FRAME_SHORT ( ySuperscriptXOffset ),
968         FT_FRAME_SHORT ( ySuperscriptYOffset ),
969         FT_FRAME_SHORT ( yStrikeoutSize ),
970         FT_FRAME_SHORT ( yStrikeoutPosition ),
971         FT_FRAME_SHORT ( sFamilyClass ),
972         FT_FRAME_BYTE  ( panose[0] ),
973         FT_FRAME_BYTE  ( panose[1] ),
974         FT_FRAME_BYTE  ( panose[2] ),
975         FT_FRAME_BYTE  ( panose[3] ),
976         FT_FRAME_BYTE  ( panose[4] ),
977         FT_FRAME_BYTE  ( panose[5] ),
978         FT_FRAME_BYTE  ( panose[6] ),
979         FT_FRAME_BYTE  ( panose[7] ),
980         FT_FRAME_BYTE  ( panose[8] ),
981         FT_FRAME_BYTE  ( panose[9] ),
982         FT_FRAME_ULONG ( ulUnicodeRange1 ),
983         FT_FRAME_ULONG ( ulUnicodeRange2 ),
984         FT_FRAME_ULONG ( ulUnicodeRange3 ),
985         FT_FRAME_ULONG ( ulUnicodeRange4 ),
986         FT_FRAME_BYTE  ( achVendID[0] ),
987         FT_FRAME_BYTE  ( achVendID[1] ),
988         FT_FRAME_BYTE  ( achVendID[2] ),
989         FT_FRAME_BYTE  ( achVendID[3] ),
990 
991         FT_FRAME_USHORT( fsSelection ),
992         FT_FRAME_USHORT( usFirstCharIndex ),
993         FT_FRAME_USHORT( usLastCharIndex ),
994         FT_FRAME_SHORT ( sTypoAscender ),
995         FT_FRAME_SHORT ( sTypoDescender ),
996         FT_FRAME_SHORT ( sTypoLineGap ),
997         FT_FRAME_USHORT( usWinAscent ),
998         FT_FRAME_USHORT( usWinDescent ),
999       FT_FRAME_END
1000     };
1001 
1002     const FT_Frame_Field  os2_fields_extra[] =
1003     {
1004       FT_FRAME_START( 8 ),
1005         FT_FRAME_ULONG( ulCodePageRange1 ),
1006         FT_FRAME_ULONG( ulCodePageRange2 ),
1007       FT_FRAME_END
1008     };
1009 
1010     const FT_Frame_Field  os2_fields_extra2[] =
1011     {
1012       FT_FRAME_START( 10 ),
1013         FT_FRAME_SHORT ( sxHeight ),
1014         FT_FRAME_SHORT ( sCapHeight ),
1015         FT_FRAME_USHORT( usDefaultChar ),
1016         FT_FRAME_USHORT( usBreakChar ),
1017         FT_FRAME_USHORT( usMaxContext ),
1018       FT_FRAME_END
1019     };
1020 
1021 
1022     /* We now support old Mac fonts where the OS/2 table doesn't  */
1023     /* exist.  Simply put, we set the `version' field to 0xFFFF   */
1024     /* and test this value each time we need to access the table. */
1025     error = face->goto_table( face, TTAG_OS2, stream, 0 );
1026     if ( error )
1027       goto Exit;
1028 
1029     os2 = &face->os2;
1030 
1031     if ( FT_STREAM_READ_FIELDS( os2_fields, os2 ) )
1032       goto Exit;
1033 
1034     os2->ulCodePageRange1 = 0;
1035     os2->ulCodePageRange2 = 0;
1036     os2->sxHeight         = 0;
1037     os2->sCapHeight       = 0;
1038     os2->usDefaultChar    = 0;
1039     os2->usBreakChar      = 0;
1040     os2->usMaxContext     = 0;
1041 
1042     if ( os2->version >= 0x0001 )
1043     {
1044       /* only version 1 tables */
1045       if ( FT_STREAM_READ_FIELDS( os2_fields_extra, os2 ) )
1046         goto Exit;
1047 
1048       if ( os2->version >= 0x0002 )
1049       {
1050         /* only version 2 tables */
1051         if ( FT_STREAM_READ_FIELDS( os2_fields_extra2, os2 ) )
1052           goto Exit;
1053       }
1054     }
1055 
1056     FT_TRACE3(( "sTypoAscender:  %4d\n",   os2->sTypoAscender ));
1057     FT_TRACE3(( "sTypoDescender: %4d\n",   os2->sTypoDescender ));
1058     FT_TRACE3(( "usWinAscent:    %4u\n",   os2->usWinAscent ));
1059     FT_TRACE3(( "usWinDescent:   %4u\n",   os2->usWinDescent ));
1060     FT_TRACE3(( "fsSelection:    0x%2x\n", os2->fsSelection ));
1061 
1062   Exit:
1063     return error;
1064   }
1065 
1066 
1067   /*************************************************************************/
1068   /*                                                                       */
1069   /* <Function>                                                            */
1070   /*    tt_face_load_postscript                                            */
1071   /*                                                                       */
1072   /* <Description>                                                         */
1073   /*    Loads the Postscript table.                                        */
1074   /*                                                                       */
1075   /* <Input>                                                               */
1076   /*    face   :: A handle to the target face object.                      */
1077   /*                                                                       */
1078   /*    stream :: A handle to the input stream.                            */
1079   /*                                                                       */
1080   /* <Return>                                                              */
1081   /*    FreeType error code.  0 means success.                             */
1082   /*                                                                       */
1083   FT_LOCAL_DEF( FT_Error )
tt_face_load_post(TT_Face face,FT_Stream stream)1084   tt_face_load_post( TT_Face    face,
1085                      FT_Stream  stream )
1086   {
1087     FT_Error        error;
1088     TT_Postscript*  post = &face->postscript;
1089 
1090     static const FT_Frame_Field  post_fields[] =
1091     {
1092 #undef  FT_STRUCTURE
1093 #define FT_STRUCTURE  TT_Postscript
1094 
1095       FT_FRAME_START( 32 ),
1096         FT_FRAME_ULONG( FormatType ),
1097         FT_FRAME_ULONG( italicAngle ),
1098         FT_FRAME_SHORT( underlinePosition ),
1099         FT_FRAME_SHORT( underlineThickness ),
1100         FT_FRAME_ULONG( isFixedPitch ),
1101         FT_FRAME_ULONG( minMemType42 ),
1102         FT_FRAME_ULONG( maxMemType42 ),
1103         FT_FRAME_ULONG( minMemType1 ),
1104         FT_FRAME_ULONG( maxMemType1 ),
1105       FT_FRAME_END
1106     };
1107 
1108 
1109     error = face->goto_table( face, TTAG_post, stream, 0 );
1110     if ( error )
1111       return error;
1112 
1113     if ( FT_STREAM_READ_FIELDS( post_fields, post ) )
1114       return error;
1115 
1116     /* we don't load the glyph names, we do that in another */
1117     /* module (ttpost).                                     */
1118 
1119     FT_TRACE3(( "FormatType:   0x%x\n", post->FormatType ));
1120     FT_TRACE3(( "isFixedPitch:   %s\n", post->isFixedPitch
1121                                         ? "  yes" : "   no" ));
1122 
1123     return SFNT_Err_Ok;
1124   }
1125 
1126 
1127   /*************************************************************************/
1128   /*                                                                       */
1129   /* <Function>                                                            */
1130   /*    tt_face_load_pclt                                                  */
1131   /*                                                                       */
1132   /* <Description>                                                         */
1133   /*    Loads the PCL 5 Table.                                             */
1134   /*                                                                       */
1135   /* <Input>                                                               */
1136   /*    face   :: A handle to the target face object.                      */
1137   /*                                                                       */
1138   /*    stream :: A handle to the input stream.                            */
1139   /*                                                                       */
1140   /* <Return>                                                              */
1141   /*    FreeType error code.  0 means success.                             */
1142   /*                                                                       */
1143   FT_LOCAL_DEF( FT_Error )
tt_face_load_pclt(TT_Face face,FT_Stream stream)1144   tt_face_load_pclt( TT_Face    face,
1145                      FT_Stream  stream )
1146   {
1147     static const FT_Frame_Field  pclt_fields[] =
1148     {
1149 #undef  FT_STRUCTURE
1150 #define FT_STRUCTURE  TT_PCLT
1151 
1152       FT_FRAME_START( 54 ),
1153         FT_FRAME_ULONG ( Version ),
1154         FT_FRAME_ULONG ( FontNumber ),
1155         FT_FRAME_USHORT( Pitch ),
1156         FT_FRAME_USHORT( xHeight ),
1157         FT_FRAME_USHORT( Style ),
1158         FT_FRAME_USHORT( TypeFamily ),
1159         FT_FRAME_USHORT( CapHeight ),
1160         FT_FRAME_BYTES ( TypeFace, 16 ),
1161         FT_FRAME_BYTES ( CharacterComplement, 8 ),
1162         FT_FRAME_BYTES ( FileName, 6 ),
1163         FT_FRAME_CHAR  ( StrokeWeight ),
1164         FT_FRAME_CHAR  ( WidthType ),
1165         FT_FRAME_BYTE  ( SerifStyle ),
1166         FT_FRAME_BYTE  ( Reserved ),
1167       FT_FRAME_END
1168     };
1169 
1170     FT_Error  error;
1171     TT_PCLT*  pclt = &face->pclt;
1172 
1173 
1174     /* optional table */
1175     error = face->goto_table( face, TTAG_PCLT, stream, 0 );
1176     if ( error )
1177       goto Exit;
1178 
1179     if ( FT_STREAM_READ_FIELDS( pclt_fields, pclt ) )
1180       goto Exit;
1181 
1182   Exit:
1183     return error;
1184   }
1185 
1186 
1187   /*************************************************************************/
1188   /*                                                                       */
1189   /* <Function>                                                            */
1190   /*    tt_face_load_gasp                                                  */
1191   /*                                                                       */
1192   /* <Description>                                                         */
1193   /*    Loads the `gasp' table into a face object.                         */
1194   /*                                                                       */
1195   /* <Input>                                                               */
1196   /*    face   :: A handle to the target face object.                      */
1197   /*                                                                       */
1198   /*    stream :: The input stream.                                        */
1199   /*                                                                       */
1200   /* <Return>                                                              */
1201   /*    FreeType error code.  0 means success.                             */
1202   /*                                                                       */
1203   FT_LOCAL_DEF( FT_Error )
tt_face_load_gasp(TT_Face face,FT_Stream stream)1204   tt_face_load_gasp( TT_Face    face,
1205                      FT_Stream  stream )
1206   {
1207     FT_Error   error;
1208     FT_Memory  memory = stream->memory;
1209 
1210     FT_UInt        j,num_ranges;
1211     TT_GaspRange   gaspranges;
1212 
1213 
1214     /* the gasp table is optional */
1215     error = face->goto_table( face, TTAG_gasp, stream, 0 );
1216     if ( error )
1217       goto Exit;
1218 
1219     if ( FT_FRAME_ENTER( 4L ) )
1220       goto Exit;
1221 
1222     face->gasp.version   = FT_GET_USHORT();
1223     face->gasp.numRanges = FT_GET_USHORT();
1224 
1225     FT_FRAME_EXIT();
1226 
1227     /* only support versions 0 and 1 of the table */
1228     if ( face->gasp.version >= 2 )
1229     {
1230       face->gasp.numRanges = 0;
1231       error = SFNT_Err_Invalid_Table;
1232       goto Exit;
1233     }
1234 
1235     num_ranges = face->gasp.numRanges;
1236     FT_TRACE3(( "numRanges: %u\n", num_ranges ));
1237 
1238     if ( FT_QNEW_ARRAY( gaspranges, num_ranges ) ||
1239          FT_FRAME_ENTER( num_ranges * 4L )      )
1240       goto Exit;
1241 
1242     face->gasp.gaspRanges = gaspranges;
1243 
1244     for ( j = 0; j < num_ranges; j++ )
1245     {
1246       gaspranges[j].maxPPEM  = FT_GET_USHORT();
1247       gaspranges[j].gaspFlag = FT_GET_USHORT();
1248 
1249       FT_TRACE3(( "gaspRange %d: rangeMaxPPEM %5d, rangeGaspBehavior 0x%x\n",
1250                   j,
1251                   gaspranges[j].maxPPEM,
1252                   gaspranges[j].gaspFlag ));
1253     }
1254 
1255     FT_FRAME_EXIT();
1256 
1257   Exit:
1258     return error;
1259   }
1260 
1261 
1262 /* END */
1263