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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 1996-2010, 2012, 2013 by                                     */
9 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
10 /*                                                                         */
11 /*  This file is part of the FreeType project, and may only be used,       */
12 /*  modified, and distributed under the terms of the FreeType project      */
13 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
14 /*  this file you indicate that you have read the license and              */
15 /*  understand and accept it fully.                                        */
16 /*                                                                         */
17 /***************************************************************************/
18 
19 
20 #include <ft2build.h>
21 #include FT_INTERNAL_DEBUG_H
22 #include FT_INTERNAL_STREAM_H
23 #include FT_TRUETYPE_TAGS_H
24 #include "ttload.h"
25 
26 #include "sferrors.h"
27 
28 
29   /*************************************************************************/
30   /*                                                                       */
31   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
32   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
33   /* messages during execution.                                            */
34   /*                                                                       */
35 #undef  FT_COMPONENT
36 #define FT_COMPONENT  trace_ttload
37 
38 
39   /*************************************************************************/
40   /*                                                                       */
41   /* <Function>                                                            */
42   /*    tt_face_lookup_table                                               */
43   /*                                                                       */
44   /* <Description>                                                         */
45   /*    Looks for a TrueType table by name.                                */
46   /*                                                                       */
47   /* <Input>                                                               */
48   /*    face :: A face object handle.                                      */
49   /*                                                                       */
50   /*    tag  :: The searched tag.                                          */
51   /*                                                                       */
52   /* <Return>                                                              */
53   /*    A pointer to the table directory entry.  0 if not found.           */
54   /*                                                                       */
55   FT_LOCAL_DEF( TT_Table  )
tt_face_lookup_table(TT_Face face,FT_ULong tag)56   tt_face_lookup_table( TT_Face   face,
57                         FT_ULong  tag  )
58   {
59     TT_Table  entry;
60     TT_Table  limit;
61 #ifdef FT_DEBUG_LEVEL_TRACE
62     FT_Bool   zero_length = FALSE;
63 #endif
64 
65 
66     FT_TRACE4(( "tt_face_lookup_table: %08p, `%c%c%c%c' -- ",
67                 face,
68                 (FT_Char)( tag >> 24 ),
69                 (FT_Char)( tag >> 16 ),
70                 (FT_Char)( tag >> 8  ),
71                 (FT_Char)( tag       ) ));
72 
73     entry = face->dir_tables;
74     limit = entry + face->num_tables;
75 
76     for ( ; entry < limit; entry++ )
77     {
78       /* For compatibility with Windows, we consider    */
79       /* zero-length tables the same as missing tables. */
80       if ( entry->Tag == tag )
81       {
82         if ( entry->Length != 0 )
83         {
84           FT_TRACE4(( "found table.\n" ));
85           return entry;
86         }
87 #ifdef FT_DEBUG_LEVEL_TRACE
88         zero_length = TRUE;
89 #endif
90       }
91     }
92 
93 #ifdef FT_DEBUG_LEVEL_TRACE
94     if ( zero_length )
95       FT_TRACE4(( "ignoring empty table\n" ));
96     else
97       FT_TRACE4(( "could not find table\n" ));
98 #endif
99 
100     return NULL;
101   }
102 
103 
104   /*************************************************************************/
105   /*                                                                       */
106   /* <Function>                                                            */
107   /*    tt_face_goto_table                                                 */
108   /*                                                                       */
109   /* <Description>                                                         */
110   /*    Looks for a TrueType table by name, then seek a stream to it.      */
111   /*                                                                       */
112   /* <Input>                                                               */
113   /*    face   :: A face object handle.                                    */
114   /*                                                                       */
115   /*    tag    :: The searched tag.                                        */
116   /*                                                                       */
117   /*    stream :: The stream to seek when the table is found.              */
118   /*                                                                       */
119   /* <Output>                                                              */
120   /*    length :: The length of the table if found, undefined otherwise.   */
121   /*                                                                       */
122   /* <Return>                                                              */
123   /*    FreeType error code.  0 means success.                             */
124   /*                                                                       */
125   FT_LOCAL_DEF( FT_Error )
tt_face_goto_table(TT_Face face,FT_ULong tag,FT_Stream stream,FT_ULong * length)126   tt_face_goto_table( TT_Face    face,
127                       FT_ULong   tag,
128                       FT_Stream  stream,
129                       FT_ULong*  length )
130   {
131     TT_Table  table;
132     FT_Error  error;
133 
134 
135     table = tt_face_lookup_table( face, tag );
136     if ( table )
137     {
138       if ( length )
139         *length = table->Length;
140 
141       if ( FT_STREAM_SEEK( table->Offset ) )
142         goto Exit;
143     }
144     else
145       error = FT_THROW( Table_Missing );
146 
147   Exit:
148     return error;
149   }
150 
151 
152   /* Here, we                                                         */
153   /*                                                                  */
154   /* - check that `num_tables' is valid (and adjust it if necessary)  */
155   /*                                                                  */
156   /* - look for a `head' table, check its size, and parse it to check */
157   /*   whether its `magic' field is correctly set                     */
158   /*                                                                  */
159   /* - errors (except errors returned by stream handling)             */
160   /*                                                                  */
161   /*     SFNT_Err_Unknown_File_Format:                                */
162   /*       no table is defined in directory, it is not sfnt-wrapped   */
163   /*       data                                                       */
164   /*     SFNT_Err_Table_Missing:                                      */
165   /*       table directory is valid, but essential tables             */
166   /*       (head/bhed/SING) are missing                               */
167   /*                                                                  */
168   static FT_Error
check_table_dir(SFNT_Header sfnt,FT_Stream stream)169   check_table_dir( SFNT_Header  sfnt,
170                    FT_Stream    stream )
171   {
172     FT_Error   error;
173     FT_UShort  nn, valid_entries = 0;
174     FT_UInt    has_head = 0, has_sing = 0, has_meta = 0;
175     FT_ULong   offset = sfnt->offset + 12;
176 
177     static const FT_Frame_Field  table_dir_entry_fields[] =
178     {
179 #undef  FT_STRUCTURE
180 #define FT_STRUCTURE  TT_TableRec
181 
182       FT_FRAME_START( 16 ),
183         FT_FRAME_ULONG( Tag ),
184         FT_FRAME_ULONG( CheckSum ),
185         FT_FRAME_ULONG( Offset ),
186         FT_FRAME_ULONG( Length ),
187       FT_FRAME_END
188     };
189 
190 
191     if ( FT_STREAM_SEEK( offset ) )
192       goto Exit;
193 
194     for ( nn = 0; nn < sfnt->num_tables; nn++ )
195     {
196       TT_TableRec  table;
197 
198 
199       if ( FT_STREAM_READ_FIELDS( table_dir_entry_fields, &table ) )
200       {
201         nn--;
202         FT_TRACE2(( "check_table_dir:"
203                     " can read only %d table%s in font (instead of %d)\n",
204                     nn, nn == 1 ? "" : "s", sfnt->num_tables ));
205         sfnt->num_tables = nn;
206         break;
207       }
208 
209       /* we ignore invalid tables */
210       if ( table.Offset + table.Length > stream->size )
211       {
212         FT_TRACE2(( "check_table_dir: table entry %d invalid\n", nn ));
213         continue;
214       }
215       else
216         valid_entries++;
217 
218       if ( table.Tag == TTAG_head || table.Tag == TTAG_bhed )
219       {
220         FT_UInt32  magic;
221 
222 
223 #ifndef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
224         if ( table.Tag == TTAG_head )
225 #endif
226           has_head = 1;
227 
228         /*
229          * The table length should be 0x36, but certain font tools make it
230          * 0x38, so we will just check that it is greater.
231          *
232          * Note that according to the specification, the table must be
233          * padded to 32-bit lengths, but this doesn't apply to the value of
234          * its `Length' field!
235          *
236          */
237         if ( table.Length < 0x36 )
238         {
239           FT_TRACE2(( "check_table_dir:"
240                       " `head' or `bhed' table too small\n" ));
241           error = FT_THROW( 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           FT_TRACE2(( "check_table_dir:"
251                       " invalid magic number in `head' or `bhed' table\n"));
252 
253         if ( FT_STREAM_SEEK( offset + ( nn + 1 ) * 16 ) )
254           goto Exit;
255       }
256       else if ( table.Tag == TTAG_SING )
257         has_sing = 1;
258       else if ( table.Tag == TTAG_META )
259         has_meta = 1;
260     }
261 
262     sfnt->num_tables = valid_entries;
263 
264     if ( sfnt->num_tables == 0 )
265     {
266       FT_TRACE2(( "check_table_dir: no tables found\n" ));
267       error = FT_THROW( Unknown_File_Format );
268       goto Exit;
269     }
270 
271     /* if `sing' and `meta' tables are present, there is no `head' table */
272     if ( has_head || ( has_sing && has_meta ) )
273     {
274       error = FT_Err_Ok;
275       goto Exit;
276     }
277     else
278     {
279       FT_TRACE2(( "check_table_dir:" ));
280 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
281       FT_TRACE2(( " neither `head', `bhed', nor `sing' table found\n" ));
282 #else
283       FT_TRACE2(( " neither `head' nor `sing' table found\n" ));
284 #endif
285       error = FT_THROW( Table_Missing );
286     }
287 
288   Exit:
289     return error;
290   }
291 
292 
293   /*************************************************************************/
294   /*                                                                       */
295   /* <Function>                                                            */
296   /*    tt_face_load_font_dir                                              */
297   /*                                                                       */
298   /* <Description>                                                         */
299   /*    Loads the header of a SFNT font file.                              */
300   /*                                                                       */
301   /* <Input>                                                               */
302   /*    face       :: A handle to the target face object.                  */
303   /*                                                                       */
304   /*    stream     :: The input stream.                                    */
305   /*                                                                       */
306   /* <Output>                                                              */
307   /*    sfnt       :: The SFNT header.                                     */
308   /*                                                                       */
309   /* <Return>                                                              */
310   /*    FreeType error code.  0 means success.                             */
311   /*                                                                       */
312   /* <Note>                                                                */
313   /*    The stream cursor must be at the beginning of the font directory.  */
314   /*                                                                       */
315   FT_LOCAL_DEF( FT_Error )
tt_face_load_font_dir(TT_Face face,FT_Stream stream)316   tt_face_load_font_dir( TT_Face    face,
317                          FT_Stream  stream )
318   {
319     SFNT_HeaderRec  sfnt;
320     FT_Error        error;
321     FT_Memory       memory = stream->memory;
322     TT_TableRec*    entry;
323     FT_Int          nn;
324 
325     static const FT_Frame_Field  offset_table_fields[] =
326     {
327 #undef  FT_STRUCTURE
328 #define FT_STRUCTURE  SFNT_HeaderRec
329 
330       FT_FRAME_START( 8 ),
331         FT_FRAME_USHORT( num_tables ),
332         FT_FRAME_USHORT( search_range ),
333         FT_FRAME_USHORT( entry_selector ),
334         FT_FRAME_USHORT( range_shift ),
335       FT_FRAME_END
336     };
337 
338 
339     FT_TRACE2(( "tt_face_load_font_dir: %08p\n", face ));
340 
341     /* read the offset table */
342 
343     sfnt.offset = FT_STREAM_POS();
344 
345     if ( FT_READ_ULONG( sfnt.format_tag )                    ||
346          FT_STREAM_READ_FIELDS( offset_table_fields, &sfnt ) )
347       goto Exit;
348 
349     /* many fonts don't have these fields set correctly */
350 #if 0
351     if ( sfnt.search_range != 1 << ( sfnt.entry_selector + 4 )        ||
352          sfnt.search_range + sfnt.range_shift != sfnt.num_tables << 4 )
353       return FT_THROW( Unknown_File_Format );
354 #endif
355 
356     /* load the table directory */
357 
358     FT_TRACE2(( "-- Number of tables: %10u\n",    sfnt.num_tables ));
359     FT_TRACE2(( "-- Format version:   0x%08lx\n", sfnt.format_tag ));
360 
361     if ( sfnt.format_tag != TTAG_OTTO )
362     {
363       /* check first */
364       error = check_table_dir( &sfnt, stream );
365       if ( error )
366       {
367         FT_TRACE2(( "tt_face_load_font_dir:"
368                     " invalid table directory for TrueType\n" ));
369 
370         goto Exit;
371       }
372     }
373 
374     face->num_tables = sfnt.num_tables;
375     face->format_tag = sfnt.format_tag;
376 
377     if ( FT_QNEW_ARRAY( face->dir_tables, face->num_tables ) )
378       goto Exit;
379 
380     if ( FT_STREAM_SEEK( sfnt.offset + 12 )       ||
381          FT_FRAME_ENTER( face->num_tables * 16L ) )
382       goto Exit;
383 
384     entry = face->dir_tables;
385 
386     FT_TRACE2(( "\n"
387                 "  tag    offset    length   checksum\n"
388                 "  ----------------------------------\n" ));
389 
390     for ( nn = 0; nn < sfnt.num_tables; nn++ )
391     {
392       entry->Tag      = FT_GET_TAG4();
393       entry->CheckSum = FT_GET_ULONG();
394       entry->Offset   = FT_GET_ULONG();
395       entry->Length   = FT_GET_ULONG();
396 
397       /* ignore invalid tables */
398       if ( entry->Offset + entry->Length > stream->size )
399         continue;
400       else
401       {
402         FT_TRACE2(( "  %c%c%c%c  %08lx  %08lx  %08lx\n",
403                     (FT_Char)( entry->Tag >> 24 ),
404                     (FT_Char)( entry->Tag >> 16 ),
405                     (FT_Char)( entry->Tag >> 8  ),
406                     (FT_Char)( entry->Tag       ),
407                     entry->Offset,
408                     entry->Length,
409                     entry->CheckSum ));
410         entry++;
411       }
412     }
413 
414     FT_FRAME_EXIT();
415 
416     FT_TRACE2(( "table directory loaded\n\n" ));
417 
418   Exit:
419     return error;
420   }
421 
422 
423   /*************************************************************************/
424   /*                                                                       */
425   /* <Function>                                                            */
426   /*    tt_face_load_any                                                   */
427   /*                                                                       */
428   /* <Description>                                                         */
429   /*    Loads any font table into client memory.                           */
430   /*                                                                       */
431   /* <Input>                                                               */
432   /*    face   :: The face object to look for.                             */
433   /*                                                                       */
434   /*    tag    :: The tag of table to load.  Use the value 0 if you want   */
435   /*              to access the whole font file, else set this parameter   */
436   /*              to a valid TrueType table tag that you can forge with    */
437   /*              the MAKE_TT_TAG macro.                                   */
438   /*                                                                       */
439   /*    offset :: The starting offset in the table (or the file if         */
440   /*              tag == 0).                                               */
441   /*                                                                       */
442   /*    length :: The address of the decision variable:                    */
443   /*                                                                       */
444   /*                If length == NULL:                                     */
445   /*                  Loads the whole table.  Returns an error if          */
446   /*                  `offset' == 0!                                       */
447   /*                                                                       */
448   /*                If *length == 0:                                       */
449   /*                  Exits immediately; returning the length of the given */
450   /*                  table or of the font file, depending on the value of */
451   /*                  `tag'.                                               */
452   /*                                                                       */
453   /*                If *length != 0:                                       */
454   /*                  Loads the next `length' bytes of table or font,      */
455   /*                  starting at offset `offset' (in table or font too).  */
456   /*                                                                       */
457   /* <Output>                                                              */
458   /*    buffer :: The address of target buffer.                            */
459   /*                                                                       */
460   /* <Return>                                                              */
461   /*    FreeType error code.  0 means success.                             */
462   /*                                                                       */
463   FT_LOCAL_DEF( FT_Error )
tt_face_load_any(TT_Face face,FT_ULong tag,FT_Long offset,FT_Byte * buffer,FT_ULong * length)464   tt_face_load_any( TT_Face    face,
465                     FT_ULong   tag,
466                     FT_Long    offset,
467                     FT_Byte*   buffer,
468                     FT_ULong*  length )
469   {
470     FT_Error   error;
471     FT_Stream  stream;
472     TT_Table   table;
473     FT_ULong   size;
474 
475 
476     if ( tag != 0 )
477     {
478       /* look for tag in font directory */
479       table = tt_face_lookup_table( face, tag );
480       if ( !table )
481       {
482         error = FT_THROW( Table_Missing );
483         goto Exit;
484       }
485 
486       offset += table->Offset;
487       size    = table->Length;
488     }
489     else
490       /* tag == 0 -- the user wants to access the font file directly */
491       size = face->root.stream->size;
492 
493     if ( length && *length == 0 )
494     {
495       *length = size;
496 
497       return FT_Err_Ok;
498     }
499 
500     if ( length )
501       size = *length;
502 
503     stream = face->root.stream;
504     /* the `if' is syntactic sugar for picky compilers */
505     if ( FT_STREAM_READ_AT( offset, buffer, size ) )
506       goto Exit;
507 
508   Exit:
509     return error;
510   }
511 
512 
513   /*************************************************************************/
514   /*                                                                       */
515   /* <Function>                                                            */
516   /*    tt_face_load_generic_header                                        */
517   /*                                                                       */
518   /* <Description>                                                         */
519   /*    Loads the TrueType table `head' or `bhed'.                         */
520   /*                                                                       */
521   /* <Input>                                                               */
522   /*    face   :: A handle to the target face object.                      */
523   /*                                                                       */
524   /*    stream :: The input stream.                                        */
525   /*                                                                       */
526   /* <Return>                                                              */
527   /*    FreeType error code.  0 means success.                             */
528   /*                                                                       */
529   static FT_Error
tt_face_load_generic_header(TT_Face face,FT_Stream stream,FT_ULong tag)530   tt_face_load_generic_header( TT_Face    face,
531                                FT_Stream  stream,
532                                FT_ULong   tag )
533   {
534     FT_Error    error;
535     TT_Header*  header;
536 
537     static const FT_Frame_Field  header_fields[] =
538     {
539 #undef  FT_STRUCTURE
540 #define FT_STRUCTURE  TT_Header
541 
542       FT_FRAME_START( 54 ),
543         FT_FRAME_ULONG ( Table_Version ),
544         FT_FRAME_ULONG ( Font_Revision ),
545         FT_FRAME_LONG  ( CheckSum_Adjust ),
546         FT_FRAME_LONG  ( Magic_Number ),
547         FT_FRAME_USHORT( Flags ),
548         FT_FRAME_USHORT( Units_Per_EM ),
549         FT_FRAME_LONG  ( Created[0] ),
550         FT_FRAME_LONG  ( Created[1] ),
551         FT_FRAME_LONG  ( Modified[0] ),
552         FT_FRAME_LONG  ( Modified[1] ),
553         FT_FRAME_SHORT ( xMin ),
554         FT_FRAME_SHORT ( yMin ),
555         FT_FRAME_SHORT ( xMax ),
556         FT_FRAME_SHORT ( yMax ),
557         FT_FRAME_USHORT( Mac_Style ),
558         FT_FRAME_USHORT( Lowest_Rec_PPEM ),
559         FT_FRAME_SHORT ( Font_Direction ),
560         FT_FRAME_SHORT ( Index_To_Loc_Format ),
561         FT_FRAME_SHORT ( Glyph_Data_Format ),
562       FT_FRAME_END
563     };
564 
565 
566     error = face->goto_table( face, tag, stream, 0 );
567     if ( error )
568       goto Exit;
569 
570     header = &face->header;
571 
572     if ( FT_STREAM_READ_FIELDS( header_fields, header ) )
573       goto Exit;
574 
575     FT_TRACE3(( "Units per EM: %4u\n", header->Units_Per_EM ));
576     FT_TRACE3(( "IndexToLoc:   %4d\n", header->Index_To_Loc_Format ));
577 
578   Exit:
579     return error;
580   }
581 
582 
583   FT_LOCAL_DEF( FT_Error )
tt_face_load_head(TT_Face face,FT_Stream stream)584   tt_face_load_head( TT_Face    face,
585                      FT_Stream  stream )
586   {
587     return tt_face_load_generic_header( face, stream, TTAG_head );
588   }
589 
590 
591 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
592 
593   FT_LOCAL_DEF( FT_Error )
tt_face_load_bhed(TT_Face face,FT_Stream stream)594   tt_face_load_bhed( TT_Face    face,
595                      FT_Stream  stream )
596   {
597     return tt_face_load_generic_header( face, stream, TTAG_bhed );
598   }
599 
600 #endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */
601 
602 
603   /*************************************************************************/
604   /*                                                                       */
605   /* <Function>                                                            */
606   /*    tt_face_load_max_profile                                           */
607   /*                                                                       */
608   /* <Description>                                                         */
609   /*    Loads the maximum profile into a face object.                      */
610   /*                                                                       */
611   /* <Input>                                                               */
612   /*    face   :: A handle to the target face object.                      */
613   /*                                                                       */
614   /*    stream :: The input stream.                                        */
615   /*                                                                       */
616   /* <Return>                                                              */
617   /*    FreeType error code.  0 means success.                             */
618   /*                                                                       */
619   FT_LOCAL_DEF( FT_Error )
tt_face_load_maxp(TT_Face face,FT_Stream stream)620   tt_face_load_maxp( TT_Face    face,
621                      FT_Stream  stream )
622   {
623     FT_Error        error;
624     TT_MaxProfile*  maxProfile = &face->max_profile;
625 
626     static const FT_Frame_Field  maxp_fields[] =
627     {
628 #undef  FT_STRUCTURE
629 #define FT_STRUCTURE  TT_MaxProfile
630 
631       FT_FRAME_START( 6 ),
632         FT_FRAME_LONG  ( version ),
633         FT_FRAME_USHORT( numGlyphs ),
634       FT_FRAME_END
635     };
636 
637     static const FT_Frame_Field  maxp_fields_extra[] =
638     {
639       FT_FRAME_START( 26 ),
640         FT_FRAME_USHORT( maxPoints ),
641         FT_FRAME_USHORT( maxContours ),
642         FT_FRAME_USHORT( maxCompositePoints ),
643         FT_FRAME_USHORT( maxCompositeContours ),
644         FT_FRAME_USHORT( maxZones ),
645         FT_FRAME_USHORT( maxTwilightPoints ),
646         FT_FRAME_USHORT( maxStorage ),
647         FT_FRAME_USHORT( maxFunctionDefs ),
648         FT_FRAME_USHORT( maxInstructionDefs ),
649         FT_FRAME_USHORT( maxStackElements ),
650         FT_FRAME_USHORT( maxSizeOfInstructions ),
651         FT_FRAME_USHORT( maxComponentElements ),
652         FT_FRAME_USHORT( maxComponentDepth ),
653       FT_FRAME_END
654     };
655 
656 
657     error = face->goto_table( face, TTAG_maxp, stream, 0 );
658     if ( error )
659       goto Exit;
660 
661     if ( FT_STREAM_READ_FIELDS( maxp_fields, maxProfile ) )
662       goto Exit;
663 
664     maxProfile->maxPoints             = 0;
665     maxProfile->maxContours           = 0;
666     maxProfile->maxCompositePoints    = 0;
667     maxProfile->maxCompositeContours  = 0;
668     maxProfile->maxZones              = 0;
669     maxProfile->maxTwilightPoints     = 0;
670     maxProfile->maxStorage            = 0;
671     maxProfile->maxFunctionDefs       = 0;
672     maxProfile->maxInstructionDefs    = 0;
673     maxProfile->maxStackElements      = 0;
674     maxProfile->maxSizeOfInstructions = 0;
675     maxProfile->maxComponentElements  = 0;
676     maxProfile->maxComponentDepth     = 0;
677 
678     if ( maxProfile->version >= 0x10000L )
679     {
680       if ( FT_STREAM_READ_FIELDS( maxp_fields_extra, maxProfile ) )
681         goto Exit;
682 
683       /* XXX: an adjustment that is necessary to load certain */
684       /*      broken fonts like `Keystrokes MT' :-(           */
685       /*                                                      */
686       /*   We allocate 64 function entries by default when    */
687       /*   the maxFunctionDefs value is smaller.              */
688 
689       if ( maxProfile->maxFunctionDefs < 64 )
690         maxProfile->maxFunctionDefs = 64;
691 
692       /* we add 4 phantom points later */
693       if ( maxProfile->maxTwilightPoints > ( 0xFFFFU - 4 ) )
694       {
695         FT_TRACE0(( "tt_face_load_maxp:"
696                     " too much twilight points in `maxp' table;\n"
697                     "                  "
698                     " some glyphs might be rendered incorrectly\n" ));
699 
700         maxProfile->maxTwilightPoints = 0xFFFFU - 4;
701       }
702 
703       /* we arbitrarily limit recursion to avoid stack exhaustion */
704       if ( maxProfile->maxComponentDepth > 100 )
705       {
706         FT_TRACE0(( "tt_face_load_maxp:"
707                     " abnormally large component depth (%d) set to 100\n",
708                     maxProfile->maxComponentDepth ));
709         maxProfile->maxComponentDepth = 100;
710       }
711     }
712 
713     FT_TRACE3(( "numGlyphs: %u\n", maxProfile->numGlyphs ));
714 
715   Exit:
716     return error;
717   }
718 
719 
720   /*************************************************************************/
721   /*                                                                       */
722   /* <Function>                                                            */
723   /*    tt_face_load_name                                                  */
724   /*                                                                       */
725   /* <Description>                                                         */
726   /*    Loads the name records.                                            */
727   /*                                                                       */
728   /* <Input>                                                               */
729   /*    face   :: A handle to the target face object.                      */
730   /*                                                                       */
731   /*    stream :: The input stream.                                        */
732   /*                                                                       */
733   /* <Return>                                                              */
734   /*    FreeType error code.  0 means success.                             */
735   /*                                                                       */
736   FT_LOCAL_DEF( FT_Error )
tt_face_load_name(TT_Face face,FT_Stream stream)737   tt_face_load_name( TT_Face    face,
738                      FT_Stream  stream )
739   {
740     FT_Error      error;
741     FT_Memory     memory = stream->memory;
742     FT_ULong      table_pos, table_len;
743     FT_ULong      storage_start, storage_limit;
744     FT_UInt       count;
745     TT_NameTable  table;
746 
747     static const FT_Frame_Field  name_table_fields[] =
748     {
749 #undef  FT_STRUCTURE
750 #define FT_STRUCTURE  TT_NameTableRec
751 
752       FT_FRAME_START( 6 ),
753         FT_FRAME_USHORT( format ),
754         FT_FRAME_USHORT( numNameRecords ),
755         FT_FRAME_USHORT( storageOffset ),
756       FT_FRAME_END
757     };
758 
759     static const FT_Frame_Field  name_record_fields[] =
760     {
761 #undef  FT_STRUCTURE
762 #define FT_STRUCTURE  TT_NameEntryRec
763 
764       /* no FT_FRAME_START */
765         FT_FRAME_USHORT( platformID ),
766         FT_FRAME_USHORT( encodingID ),
767         FT_FRAME_USHORT( languageID ),
768         FT_FRAME_USHORT( nameID ),
769         FT_FRAME_USHORT( stringLength ),
770         FT_FRAME_USHORT( stringOffset ),
771       FT_FRAME_END
772     };
773 
774 
775     table         = &face->name_table;
776     table->stream = stream;
777 
778     error = face->goto_table( face, TTAG_name, stream, &table_len );
779     if ( error )
780       goto Exit;
781 
782     table_pos = FT_STREAM_POS();
783 
784 
785     if ( FT_STREAM_READ_FIELDS( name_table_fields, table ) )
786       goto Exit;
787 
788     /* Some popular Asian fonts have an invalid `storageOffset' value   */
789     /* (it should be at least "6 + 12*num_names").  However, the string */
790     /* offsets, computed as "storageOffset + entry->stringOffset", are  */
791     /* valid pointers within the name table...                          */
792     /*                                                                  */
793     /* We thus can't check `storageOffset' right now.                   */
794     /*                                                                  */
795     storage_start = table_pos + 6 + 12*table->numNameRecords;
796     storage_limit = table_pos + table_len;
797 
798     if ( storage_start > storage_limit )
799     {
800       FT_ERROR(( "tt_face_load_name: invalid `name' table\n" ));
801       error = FT_THROW( Name_Table_Missing );
802       goto Exit;
803     }
804 
805     /* Allocate the array of name records. */
806     count                 = table->numNameRecords;
807     table->numNameRecords = 0;
808 
809     if ( FT_NEW_ARRAY( table->names, count ) ||
810          FT_FRAME_ENTER( count * 12 )        )
811       goto Exit;
812 
813     /* Load the name records and determine how much storage is needed */
814     /* to hold the strings themselves.                                */
815     {
816       TT_NameEntryRec*  entry = table->names;
817 
818 
819       for ( ; count > 0; count-- )
820       {
821         if ( FT_STREAM_READ_FIELDS( name_record_fields, entry ) )
822           continue;
823 
824         /* check that the name is not empty */
825         if ( entry->stringLength == 0 )
826           continue;
827 
828         /* check that the name string is within the table */
829         entry->stringOffset += table_pos + table->storageOffset;
830         if ( entry->stringOffset                       < storage_start ||
831              entry->stringOffset + entry->stringLength > storage_limit )
832         {
833           /* invalid entry - ignore it */
834           entry->stringOffset = 0;
835           entry->stringLength = 0;
836           continue;
837         }
838 
839         entry++;
840       }
841 
842       table->numNameRecords = (FT_UInt)( entry - table->names );
843     }
844 
845     FT_FRAME_EXIT();
846 
847     /* everything went well, update face->num_names */
848     face->num_names = (FT_UShort) table->numNameRecords;
849 
850   Exit:
851     return error;
852   }
853 
854 
855   /*************************************************************************/
856   /*                                                                       */
857   /* <Function>                                                            */
858   /*    tt_face_free_names                                                 */
859   /*                                                                       */
860   /* <Description>                                                         */
861   /*    Frees the name records.                                            */
862   /*                                                                       */
863   /* <Input>                                                               */
864   /*    face :: A handle to the target face object.                        */
865   /*                                                                       */
866   FT_LOCAL_DEF( void )
tt_face_free_name(TT_Face face)867   tt_face_free_name( TT_Face  face )
868   {
869     FT_Memory     memory = face->root.driver->root.memory;
870     TT_NameTable  table  = &face->name_table;
871     TT_NameEntry  entry  = table->names;
872     FT_UInt       count  = table->numNameRecords;
873 
874 
875     if ( table->names )
876     {
877       for ( ; count > 0; count--, entry++ )
878       {
879         FT_FREE( entry->string );
880         entry->stringLength = 0;
881       }
882 
883       /* free strings table */
884       FT_FREE( table->names );
885     }
886 
887     table->numNameRecords = 0;
888     table->format         = 0;
889     table->storageOffset  = 0;
890   }
891 
892 
893   /*************************************************************************/
894   /*                                                                       */
895   /* <Function>                                                            */
896   /*    tt_face_load_cmap                                                  */
897   /*                                                                       */
898   /* <Description>                                                         */
899   /*    Loads the cmap directory in a face object.  The cmaps themselves   */
900   /*    are loaded on demand in the `ttcmap.c' module.                     */
901   /*                                                                       */
902   /* <Input>                                                               */
903   /*    face   :: A handle to the target face object.                      */
904   /*                                                                       */
905   /*    stream :: A handle to the input stream.                            */
906   /*                                                                       */
907   /* <Return>                                                              */
908   /*    FreeType error code.  0 means success.                             */
909   /*                                                                       */
910 
911   FT_LOCAL_DEF( FT_Error )
tt_face_load_cmap(TT_Face face,FT_Stream stream)912   tt_face_load_cmap( TT_Face    face,
913                      FT_Stream  stream )
914   {
915     FT_Error  error;
916 
917 
918     error = face->goto_table( face, TTAG_cmap, stream, &face->cmap_size );
919     if ( error )
920       goto Exit;
921 
922     if ( FT_FRAME_EXTRACT( face->cmap_size, face->cmap_table ) )
923       face->cmap_size = 0;
924 
925   Exit:
926     return error;
927   }
928 
929 
930 
931   /*************************************************************************/
932   /*                                                                       */
933   /* <Function>                                                            */
934   /*    tt_face_load_os2                                                   */
935   /*                                                                       */
936   /* <Description>                                                         */
937   /*    Loads the OS2 table.                                               */
938   /*                                                                       */
939   /* <Input>                                                               */
940   /*    face   :: A handle to the target face object.                      */
941   /*                                                                       */
942   /*    stream :: A handle to the input stream.                            */
943   /*                                                                       */
944   /* <Return>                                                              */
945   /*    FreeType error code.  0 means success.                             */
946   /*                                                                       */
947   FT_LOCAL_DEF( FT_Error )
tt_face_load_os2(TT_Face face,FT_Stream stream)948   tt_face_load_os2( TT_Face    face,
949                     FT_Stream  stream )
950   {
951     FT_Error  error;
952     TT_OS2*   os2;
953 
954     static const FT_Frame_Field  os2_fields[] =
955     {
956 #undef  FT_STRUCTURE
957 #define FT_STRUCTURE  TT_OS2
958 
959       FT_FRAME_START( 78 ),
960         FT_FRAME_USHORT( version ),
961         FT_FRAME_SHORT ( xAvgCharWidth ),
962         FT_FRAME_USHORT( usWeightClass ),
963         FT_FRAME_USHORT( usWidthClass ),
964         FT_FRAME_SHORT ( fsType ),
965         FT_FRAME_SHORT ( ySubscriptXSize ),
966         FT_FRAME_SHORT ( ySubscriptYSize ),
967         FT_FRAME_SHORT ( ySubscriptXOffset ),
968         FT_FRAME_SHORT ( ySubscriptYOffset ),
969         FT_FRAME_SHORT ( ySuperscriptXSize ),
970         FT_FRAME_SHORT ( ySuperscriptYSize ),
971         FT_FRAME_SHORT ( ySuperscriptXOffset ),
972         FT_FRAME_SHORT ( ySuperscriptYOffset ),
973         FT_FRAME_SHORT ( yStrikeoutSize ),
974         FT_FRAME_SHORT ( yStrikeoutPosition ),
975         FT_FRAME_SHORT ( sFamilyClass ),
976         FT_FRAME_BYTE  ( panose[0] ),
977         FT_FRAME_BYTE  ( panose[1] ),
978         FT_FRAME_BYTE  ( panose[2] ),
979         FT_FRAME_BYTE  ( panose[3] ),
980         FT_FRAME_BYTE  ( panose[4] ),
981         FT_FRAME_BYTE  ( panose[5] ),
982         FT_FRAME_BYTE  ( panose[6] ),
983         FT_FRAME_BYTE  ( panose[7] ),
984         FT_FRAME_BYTE  ( panose[8] ),
985         FT_FRAME_BYTE  ( panose[9] ),
986         FT_FRAME_ULONG ( ulUnicodeRange1 ),
987         FT_FRAME_ULONG ( ulUnicodeRange2 ),
988         FT_FRAME_ULONG ( ulUnicodeRange3 ),
989         FT_FRAME_ULONG ( ulUnicodeRange4 ),
990         FT_FRAME_BYTE  ( achVendID[0] ),
991         FT_FRAME_BYTE  ( achVendID[1] ),
992         FT_FRAME_BYTE  ( achVendID[2] ),
993         FT_FRAME_BYTE  ( achVendID[3] ),
994 
995         FT_FRAME_USHORT( fsSelection ),
996         FT_FRAME_USHORT( usFirstCharIndex ),
997         FT_FRAME_USHORT( usLastCharIndex ),
998         FT_FRAME_SHORT ( sTypoAscender ),
999         FT_FRAME_SHORT ( sTypoDescender ),
1000         FT_FRAME_SHORT ( sTypoLineGap ),
1001         FT_FRAME_USHORT( usWinAscent ),
1002         FT_FRAME_USHORT( usWinDescent ),
1003       FT_FRAME_END
1004     };
1005 
1006     /* `OS/2' version 1 and newer */
1007     static const FT_Frame_Field  os2_fields_extra1[] =
1008     {
1009       FT_FRAME_START( 8 ),
1010         FT_FRAME_ULONG( ulCodePageRange1 ),
1011         FT_FRAME_ULONG( ulCodePageRange2 ),
1012       FT_FRAME_END
1013     };
1014 
1015     /* `OS/2' version 2 and newer */
1016     static const FT_Frame_Field  os2_fields_extra2[] =
1017     {
1018       FT_FRAME_START( 10 ),
1019         FT_FRAME_SHORT ( sxHeight ),
1020         FT_FRAME_SHORT ( sCapHeight ),
1021         FT_FRAME_USHORT( usDefaultChar ),
1022         FT_FRAME_USHORT( usBreakChar ),
1023         FT_FRAME_USHORT( usMaxContext ),
1024       FT_FRAME_END
1025     };
1026 
1027     /* `OS/2' version 5 and newer */
1028     static const FT_Frame_Field  os2_fields_extra5[] =
1029     {
1030       FT_FRAME_START( 4 ),
1031         FT_FRAME_USHORT( usLowerOpticalPointSize ),
1032         FT_FRAME_USHORT( usUpperOpticalPointSize ),
1033       FT_FRAME_END
1034     };
1035 
1036 
1037     /* We now support old Mac fonts where the OS/2 table doesn't  */
1038     /* exist.  Simply put, we set the `version' field to 0xFFFF   */
1039     /* and test this value each time we need to access the table. */
1040     error = face->goto_table( face, TTAG_OS2, stream, 0 );
1041     if ( error )
1042       goto Exit;
1043 
1044     os2 = &face->os2;
1045 
1046     if ( FT_STREAM_READ_FIELDS( os2_fields, os2 ) )
1047       goto Exit;
1048 
1049     os2->ulCodePageRange1        = 0;
1050     os2->ulCodePageRange2        = 0;
1051     os2->sxHeight                = 0;
1052     os2->sCapHeight              = 0;
1053     os2->usDefaultChar           = 0;
1054     os2->usBreakChar             = 0;
1055     os2->usMaxContext            = 0;
1056     os2->usLowerOpticalPointSize = 0;
1057     os2->usUpperOpticalPointSize = 0xFFFF;
1058 
1059     if ( os2->version >= 0x0001 )
1060     {
1061       /* only version 1 tables */
1062       if ( FT_STREAM_READ_FIELDS( os2_fields_extra1, os2 ) )
1063         goto Exit;
1064 
1065       if ( os2->version >= 0x0002 )
1066       {
1067         /* only version 2 tables */
1068         if ( FT_STREAM_READ_FIELDS( os2_fields_extra2, os2 ) )
1069           goto Exit;
1070 
1071         if ( os2->version >= 0x0005 )
1072         {
1073           /* only version 5 tables */
1074           if ( FT_STREAM_READ_FIELDS( os2_fields_extra5, os2 ) )
1075             goto Exit;
1076         }
1077       }
1078     }
1079 
1080     FT_TRACE3(( "sTypoAscender:  %4d\n",   os2->sTypoAscender ));
1081     FT_TRACE3(( "sTypoDescender: %4d\n",   os2->sTypoDescender ));
1082     FT_TRACE3(( "usWinAscent:    %4u\n",   os2->usWinAscent ));
1083     FT_TRACE3(( "usWinDescent:   %4u\n",   os2->usWinDescent ));
1084     FT_TRACE3(( "fsSelection:    0x%2x\n", os2->fsSelection ));
1085 
1086   Exit:
1087     return error;
1088   }
1089 
1090 
1091   /*************************************************************************/
1092   /*                                                                       */
1093   /* <Function>                                                            */
1094   /*    tt_face_load_postscript                                            */
1095   /*                                                                       */
1096   /* <Description>                                                         */
1097   /*    Loads the Postscript table.                                        */
1098   /*                                                                       */
1099   /* <Input>                                                               */
1100   /*    face   :: A handle to the target face object.                      */
1101   /*                                                                       */
1102   /*    stream :: A handle to the input stream.                            */
1103   /*                                                                       */
1104   /* <Return>                                                              */
1105   /*    FreeType error code.  0 means success.                             */
1106   /*                                                                       */
1107   FT_LOCAL_DEF( FT_Error )
tt_face_load_post(TT_Face face,FT_Stream stream)1108   tt_face_load_post( TT_Face    face,
1109                      FT_Stream  stream )
1110   {
1111     FT_Error        error;
1112     TT_Postscript*  post = &face->postscript;
1113 
1114     static const FT_Frame_Field  post_fields[] =
1115     {
1116 #undef  FT_STRUCTURE
1117 #define FT_STRUCTURE  TT_Postscript
1118 
1119       FT_FRAME_START( 32 ),
1120         FT_FRAME_ULONG( FormatType ),
1121         FT_FRAME_ULONG( italicAngle ),
1122         FT_FRAME_SHORT( underlinePosition ),
1123         FT_FRAME_SHORT( underlineThickness ),
1124         FT_FRAME_ULONG( isFixedPitch ),
1125         FT_FRAME_ULONG( minMemType42 ),
1126         FT_FRAME_ULONG( maxMemType42 ),
1127         FT_FRAME_ULONG( minMemType1 ),
1128         FT_FRAME_ULONG( maxMemType1 ),
1129       FT_FRAME_END
1130     };
1131 
1132 
1133     error = face->goto_table( face, TTAG_post, stream, 0 );
1134     if ( error )
1135       return error;
1136 
1137     if ( FT_STREAM_READ_FIELDS( post_fields, post ) )
1138       return error;
1139 
1140     /* we don't load the glyph names, we do that in another */
1141     /* module (ttpost).                                     */
1142 
1143     FT_TRACE3(( "FormatType:   0x%x\n", post->FormatType ));
1144     FT_TRACE3(( "isFixedPitch:   %s\n", post->isFixedPitch
1145                                         ? "  yes" : "   no" ));
1146 
1147     return FT_Err_Ok;
1148   }
1149 
1150 
1151   /*************************************************************************/
1152   /*                                                                       */
1153   /* <Function>                                                            */
1154   /*    tt_face_load_pclt                                                  */
1155   /*                                                                       */
1156   /* <Description>                                                         */
1157   /*    Loads the PCL 5 Table.                                             */
1158   /*                                                                       */
1159   /* <Input>                                                               */
1160   /*    face   :: A handle to the target face object.                      */
1161   /*                                                                       */
1162   /*    stream :: A handle to the input stream.                            */
1163   /*                                                                       */
1164   /* <Return>                                                              */
1165   /*    FreeType error code.  0 means success.                             */
1166   /*                                                                       */
1167   FT_LOCAL_DEF( FT_Error )
tt_face_load_pclt(TT_Face face,FT_Stream stream)1168   tt_face_load_pclt( TT_Face    face,
1169                      FT_Stream  stream )
1170   {
1171     static const FT_Frame_Field  pclt_fields[] =
1172     {
1173 #undef  FT_STRUCTURE
1174 #define FT_STRUCTURE  TT_PCLT
1175 
1176       FT_FRAME_START( 54 ),
1177         FT_FRAME_ULONG ( Version ),
1178         FT_FRAME_ULONG ( FontNumber ),
1179         FT_FRAME_USHORT( Pitch ),
1180         FT_FRAME_USHORT( xHeight ),
1181         FT_FRAME_USHORT( Style ),
1182         FT_FRAME_USHORT( TypeFamily ),
1183         FT_FRAME_USHORT( CapHeight ),
1184         FT_FRAME_USHORT( SymbolSet ),
1185         FT_FRAME_BYTES ( TypeFace, 16 ),
1186         FT_FRAME_BYTES ( CharacterComplement, 8 ),
1187         FT_FRAME_BYTES ( FileName, 6 ),
1188         FT_FRAME_CHAR  ( StrokeWeight ),
1189         FT_FRAME_CHAR  ( WidthType ),
1190         FT_FRAME_BYTE  ( SerifStyle ),
1191         FT_FRAME_BYTE  ( Reserved ),
1192       FT_FRAME_END
1193     };
1194 
1195     FT_Error  error;
1196     TT_PCLT*  pclt = &face->pclt;
1197 
1198 
1199     /* optional table */
1200     error = face->goto_table( face, TTAG_PCLT, stream, 0 );
1201     if ( error )
1202       goto Exit;
1203 
1204     if ( FT_STREAM_READ_FIELDS( pclt_fields, pclt ) )
1205       goto Exit;
1206 
1207   Exit:
1208     return error;
1209   }
1210 
1211 
1212   /*************************************************************************/
1213   /*                                                                       */
1214   /* <Function>                                                            */
1215   /*    tt_face_load_gasp                                                  */
1216   /*                                                                       */
1217   /* <Description>                                                         */
1218   /*    Loads the `gasp' table into a face object.                         */
1219   /*                                                                       */
1220   /* <Input>                                                               */
1221   /*    face   :: A handle to the target face object.                      */
1222   /*                                                                       */
1223   /*    stream :: The input stream.                                        */
1224   /*                                                                       */
1225   /* <Return>                                                              */
1226   /*    FreeType error code.  0 means success.                             */
1227   /*                                                                       */
1228   FT_LOCAL_DEF( FT_Error )
tt_face_load_gasp(TT_Face face,FT_Stream stream)1229   tt_face_load_gasp( TT_Face    face,
1230                      FT_Stream  stream )
1231   {
1232     FT_Error   error;
1233     FT_Memory  memory = stream->memory;
1234 
1235     FT_UInt        j,num_ranges;
1236     TT_GaspRange   gaspranges = NULL;
1237 
1238 
1239     /* the gasp table is optional */
1240     error = face->goto_table( face, TTAG_gasp, stream, 0 );
1241     if ( error )
1242       goto Exit;
1243 
1244     if ( FT_FRAME_ENTER( 4L ) )
1245       goto Exit;
1246 
1247     face->gasp.version   = FT_GET_USHORT();
1248     face->gasp.numRanges = FT_GET_USHORT();
1249 
1250     FT_FRAME_EXIT();
1251 
1252     /* only support versions 0 and 1 of the table */
1253     if ( face->gasp.version >= 2 )
1254     {
1255       face->gasp.numRanges = 0;
1256       error = FT_THROW( Invalid_Table );
1257       goto Exit;
1258     }
1259 
1260     num_ranges = face->gasp.numRanges;
1261     FT_TRACE3(( "numRanges: %u\n", num_ranges ));
1262 
1263     if ( FT_QNEW_ARRAY( face->gasp.gaspRanges, num_ranges ) ||
1264          FT_FRAME_ENTER( num_ranges * 4L )                  )
1265       goto Exit;
1266 
1267     gaspranges = face->gasp.gaspRanges;
1268 
1269     for ( j = 0; j < num_ranges; j++ )
1270     {
1271       gaspranges[j].maxPPEM  = FT_GET_USHORT();
1272       gaspranges[j].gaspFlag = FT_GET_USHORT();
1273 
1274       FT_TRACE3(( "gaspRange %d: rangeMaxPPEM %5d, rangeGaspBehavior 0x%x\n",
1275                   j,
1276                   gaspranges[j].maxPPEM,
1277                   gaspranges[j].gaspFlag ));
1278     }
1279 
1280     FT_FRAME_EXIT();
1281 
1282   Exit:
1283     return error;
1284   }
1285 
1286 
1287 /* END */
1288