xref: /aosp_15_r20/external/freetype/src/pfr/pfrload.c (revision 63949dbd25bcc50c4e1178497ff9e9574d44fc5a)
1 /****************************************************************************
2  *
3  * pfrload.c
4  *
5  *   FreeType PFR loader (body).
6  *
7  * Copyright (C) 2002-2023 by
8  * David Turner, Robert Wilhelm, and Werner Lemberg.
9  *
10  * This file is part of the FreeType project, and may only be used,
11  * modified, and distributed under the terms of the FreeType project
12  * license, LICENSE.TXT.  By continuing to use, modify, or distribute
13  * this file you indicate that you have read the license and
14  * understand and accept it fully.
15  *
16  */
17 
18 
19 #include "pfrload.h"
20 #include <freetype/internal/ftdebug.h>
21 #include <freetype/internal/ftstream.h>
22 
23 #include "pfrerror.h"
24 
25 #undef  FT_COMPONENT
26 #define FT_COMPONENT  pfr
27 
28 
29   /*
30    * The overall structure of a PFR file is as follows.
31    *
32    *   PFR header
33    *     58 bytes (contains nPhysFonts)
34    *
35    *   Logical font directory (size at most 2^16 bytes)
36    *     2 bytes (nLogFonts)
37    *     + nLogFonts * 5 bytes
38    *
39    *        ==>  nLogFonts <= 13106
40    *
41    *   Logical font section (size at most 2^24 bytes)
42    *     nLogFonts * logFontRecord
43    *
44    *     logFontRecord (size at most 2^16 bytes)
45    *       12 bytes (fontMatrix)
46    *       + 1 byte (flags)
47    *       + 0-5 bytes (depending on `flags')
48    *       + 0-(1+255*(2+255)) = 0-65536 (depending on `flags')
49    *       + 5 bytes (physical font info)
50    *       + 0-1 bytes (depending on PFR header)
51    *
52    *        ==>  minimum size 18 bytes
53    *
54    *   Physical font section (size at most 2^24 bytes)
55    *     nPhysFonts * (physFontRecord
56    *                   + nBitmapSizes * nBmapChars * bmapCharRecord)
57    *
58    *     physFontRecord (size at most 2^24 bytes)
59    *       14 bytes (font info)
60    *       + 1 byte (flags)
61    *       + 0-2 (depending on `flags')
62    *       + 0-? (structure too complicated to be shown here; depending on
63    *              `flags'; contains `nBitmapSizes' and `nBmapChars')
64    *       + 3 bytes (nAuxBytes)
65    *       + nAuxBytes
66    *       + 1 byte (nBlueValues)
67    *       + 2 * nBlueValues
68    *       + 6 bytes (hinting data)
69    *       + 2 bytes (nCharacters)
70    *       + nCharacters * (4-10 bytes) (depending on `flags')
71    *
72    *        ==>  minimum size 27 bytes
73    *
74    *     bmapCharRecord
75    *       4-7 bytes
76    *
77    *   Glyph program strings (three possible types: simpleGps, compoundGps,
78    *                          and bitmapGps; size at most 2^24 bytes)
79    *     simpleGps (size at most 2^16 bytes)
80    *       1 byte (flags)
81    *       1-2 bytes (n[XY]orus, depending on `flags')
82    *       0-(64+512*2) = 0-1088 bytes (depending on `n[XY]orus')
83    *       0-? (structure too complicated to be shown here; depending on
84    *            `flags')
85    *       1-? glyph data (faintly resembling PS Type 1 charstrings)
86    *
87    *        ==>  minimum size 3 bytes
88    *
89    *     compoundGps (size at most 2^16 bytes)
90    *       1 byte (nElements <= 63, flags)
91    *       + 0-(1+255*(2+255)) = 0-65536 (depending on `flags')
92    *       + nElements * (6-14 bytes)
93    *
94    *     bitmapGps (size at most 2^16 bytes)
95    *       1 byte (flags)
96    *       3-13 bytes (position info, depending on `flags')
97    *       0-? bitmap data
98    *
99    *        ==>  minimum size 4 bytes
100    *
101    *   PFR trailer
102    *       8 bytes
103    *
104    *
105    * ==>  minimum size of a valid PFR:
106    *        58 (header)
107    *        + 2 (nLogFonts)
108    *        + 27 (1 physFontRecord)
109    *        + 8 (trailer)
110    *       -----
111    *        95 bytes
112    *
113    */
114 
115 
116   /*************************************************************************/
117   /*************************************************************************/
118   /*****                                                               *****/
119   /*****                          EXTRA ITEMS                          *****/
120   /*****                                                               *****/
121   /*************************************************************************/
122   /*************************************************************************/
123 
124 
125   FT_LOCAL_DEF( FT_Error )
pfr_extra_items_skip(FT_Byte ** pp,FT_Byte * limit)126   pfr_extra_items_skip( FT_Byte*  *pp,
127                         FT_Byte*   limit )
128   {
129     return pfr_extra_items_parse( pp, limit, NULL, NULL );
130   }
131 
132 
133   FT_LOCAL_DEF( FT_Error )
pfr_extra_items_parse(FT_Byte ** pp,FT_Byte * limit,PFR_ExtraItem item_list,FT_Pointer item_data)134   pfr_extra_items_parse( FT_Byte*       *pp,
135                          FT_Byte*        limit,
136                          PFR_ExtraItem   item_list,
137                          FT_Pointer      item_data )
138   {
139     FT_Error  error = FT_Err_Ok;
140     FT_Byte*  p     = *pp;
141     FT_UInt   num_items, item_type, item_size;
142 
143 
144     PFR_CHECK( 1 );
145     num_items = PFR_NEXT_BYTE( p );
146 
147     for ( ; num_items > 0; num_items-- )
148     {
149       PFR_CHECK( 2 );
150       item_size = PFR_NEXT_BYTE( p );
151       item_type = PFR_NEXT_BYTE( p );
152 
153       PFR_CHECK( item_size );
154 
155       if ( item_list )
156       {
157         PFR_ExtraItem  extra = item_list;
158 
159 
160         for ( extra = item_list; extra->parser != NULL; extra++ )
161         {
162           if ( extra->type == item_type )
163           {
164             error = extra->parser( p, p + item_size, item_data );
165             if ( error )
166               goto Exit;
167 
168             break;
169           }
170         }
171       }
172 
173       p += item_size;
174     }
175 
176   Exit:
177     *pp = p;
178     return error;
179 
180   Too_Short:
181     FT_ERROR(( "pfr_extra_items_parse: invalid extra items table\n" ));
182     error = FT_THROW( Invalid_Table );
183     goto Exit;
184   }
185 
186 
187   /*************************************************************************/
188   /*************************************************************************/
189   /*****                                                               *****/
190   /*****                          PFR HEADER                           *****/
191   /*****                                                               *****/
192   /*************************************************************************/
193   /*************************************************************************/
194 
195    static const FT_Frame_Field  pfr_header_fields[] =
196    {
197 #undef  FT_STRUCTURE
198 #define FT_STRUCTURE  PFR_HeaderRec
199 
200      FT_FRAME_START( 58 ),
201        FT_FRAME_ULONG ( signature ),
202        FT_FRAME_USHORT( version ),
203        FT_FRAME_USHORT( signature2 ),
204        FT_FRAME_USHORT( header_size ),
205 
206        FT_FRAME_USHORT( log_dir_size ),
207        FT_FRAME_USHORT( log_dir_offset ),
208 
209        FT_FRAME_USHORT( log_font_max_size ),
210        FT_FRAME_UOFF3 ( log_font_section_size ),
211        FT_FRAME_UOFF3 ( log_font_section_offset ),
212 
213        FT_FRAME_USHORT( phy_font_max_size ),
214        FT_FRAME_UOFF3 ( phy_font_section_size ),
215        FT_FRAME_UOFF3 ( phy_font_section_offset ),
216 
217        FT_FRAME_USHORT( gps_max_size ),
218        FT_FRAME_UOFF3 ( gps_section_size ),
219        FT_FRAME_UOFF3 ( gps_section_offset ),
220 
221        FT_FRAME_BYTE  ( max_blue_values ),
222        FT_FRAME_BYTE  ( max_x_orus ),
223        FT_FRAME_BYTE  ( max_y_orus ),
224 
225        FT_FRAME_BYTE  ( phy_font_max_size_high ),
226        FT_FRAME_BYTE  ( color_flags ),
227 
228        FT_FRAME_UOFF3 ( bct_max_size ),
229        FT_FRAME_UOFF3 ( bct_set_max_size ),
230        FT_FRAME_UOFF3 ( phy_bct_set_max_size ),
231 
232        FT_FRAME_USHORT( num_phy_fonts ),
233        FT_FRAME_BYTE  ( max_vert_stem_snap ),
234        FT_FRAME_BYTE  ( max_horz_stem_snap ),
235        FT_FRAME_USHORT( max_chars ),
236      FT_FRAME_END
237    };
238 
239 
240   FT_LOCAL_DEF( FT_Error )
pfr_header_load(PFR_Header header,FT_Stream stream)241   pfr_header_load( PFR_Header  header,
242                    FT_Stream   stream )
243   {
244     FT_Error  error;
245 
246 
247     /* read header directly */
248     if ( !FT_STREAM_SEEK( 0 )                                &&
249          !FT_STREAM_READ_FIELDS( pfr_header_fields, header ) )
250     {
251       /* make a few adjustments to the header */
252       header->phy_font_max_size +=
253         (FT_UInt32)header->phy_font_max_size_high << 16;
254     }
255 
256     return error;
257   }
258 
259 
260   FT_LOCAL_DEF( FT_Bool )
pfr_header_check(PFR_Header header)261   pfr_header_check( PFR_Header  header )
262   {
263     FT_Bool  result = 1;
264 
265 
266     /* check signature and header size */
267     if ( header->signature  != 0x50465230L ||   /* "PFR0" */
268          header->version     > 4           ||
269          header->header_size < 58          ||
270          header->signature2 != 0x0D0A      )    /* CR/LF  */
271       result = 0;
272 
273     return result;
274   }
275 
276 
277   /***********************************************************************/
278   /***********************************************************************/
279   /*****                                                             *****/
280   /*****                    PFR LOGICAL FONTS                        *****/
281   /*****                                                             *****/
282   /***********************************************************************/
283   /***********************************************************************/
284 
285 
286   FT_LOCAL_DEF( FT_Error )
pfr_log_font_count(FT_Stream stream,FT_UInt32 section_offset,FT_Long * acount)287   pfr_log_font_count( FT_Stream  stream,
288                       FT_UInt32  section_offset,
289                       FT_Long   *acount )
290   {
291     FT_Error  error;
292     FT_UInt   count;
293     FT_UInt   result = 0;
294 
295 
296     if ( FT_STREAM_SEEK( section_offset ) ||
297          FT_READ_USHORT( count )          )
298       goto Exit;
299 
300     /* check maximum value and a rough minimum size:     */
301     /* - no more than 13106 log fonts                    */
302     /* - we need 5 bytes for a log header record         */
303     /* - we need at least 18 bytes for a log font record */
304     /* - the overall size is at least 95 bytes plus the  */
305     /*   log header and log font records                 */
306     if ( count > ( ( 1 << 16 ) - 2 ) / 5                ||
307          2 + count * 5 >= stream->size - section_offset ||
308          95 + count * ( 5 + 18 ) >= stream->size        )
309     {
310       FT_ERROR(( "pfr_log_font_count:"
311                  " invalid number of logical fonts\n" ));
312       error = FT_THROW( Invalid_Table );
313       goto Exit;
314     }
315 
316     result = count;
317 
318   Exit:
319     *acount = (FT_Long)result;
320     return error;
321   }
322 
323 
324   FT_LOCAL_DEF( FT_Error )
pfr_log_font_load(PFR_LogFont log_font,FT_Stream stream,FT_UInt idx,FT_UInt32 section_offset,FT_Bool size_increment)325   pfr_log_font_load( PFR_LogFont  log_font,
326                      FT_Stream    stream,
327                      FT_UInt      idx,
328                      FT_UInt32    section_offset,
329                      FT_Bool      size_increment )
330   {
331     FT_UInt    num_log_fonts;
332     FT_UInt    flags;
333     FT_UInt32  offset;
334     FT_UInt32  size;
335     FT_Error   error;
336 
337 
338     if ( FT_STREAM_SEEK( section_offset ) ||
339          FT_READ_USHORT( num_log_fonts )  )
340       goto Exit;
341 
342     if ( idx >= num_log_fonts )
343       return FT_THROW( Invalid_Argument );
344 
345     if ( FT_STREAM_SKIP( idx * 5 ) ||
346          FT_READ_USHORT( size )    ||
347          FT_READ_UOFF3 ( offset )  )
348       goto Exit;
349 
350     /* save logical font size and offset */
351     log_font->size   = size;
352     log_font->offset = offset;
353 
354     /* now, check the rest of the table before loading it */
355     {
356       FT_Byte*  p;
357       FT_Byte*  limit;
358       FT_UInt   local;
359 
360 
361       if ( FT_STREAM_SEEK( offset ) ||
362            FT_FRAME_ENTER( size )   )
363         goto Exit;
364 
365       p     = stream->cursor;
366       limit = p + size;
367 
368       PFR_CHECK( 13 );
369 
370       log_font->matrix[0] = PFR_NEXT_LONG( p );
371       log_font->matrix[1] = PFR_NEXT_LONG( p );
372       log_font->matrix[2] = PFR_NEXT_LONG( p );
373       log_font->matrix[3] = PFR_NEXT_LONG( p );
374 
375       flags = PFR_NEXT_BYTE( p );
376 
377       local = 0;
378       if ( flags & PFR_LOG_STROKE )
379       {
380         local++;
381         if ( flags & PFR_LOG_2BYTE_STROKE )
382           local++;
383 
384         if ( ( flags & PFR_LINE_JOIN_MASK ) == PFR_LINE_JOIN_MITER )
385           local += 3;
386       }
387       if ( flags & PFR_LOG_BOLD )
388       {
389         local++;
390         if ( flags & PFR_LOG_2BYTE_BOLD )
391           local++;
392       }
393 
394       PFR_CHECK( local );
395 
396       if ( flags & PFR_LOG_STROKE )
397       {
398         log_font->stroke_thickness = ( flags & PFR_LOG_2BYTE_STROKE )
399                                      ? PFR_NEXT_SHORT( p )
400                                      : PFR_NEXT_BYTE( p );
401 
402         if ( ( flags & PFR_LINE_JOIN_MASK ) == PFR_LINE_JOIN_MITER )
403           log_font->miter_limit = PFR_NEXT_LONG( p );
404       }
405 
406       if ( flags & PFR_LOG_BOLD )
407         log_font->bold_thickness = ( flags & PFR_LOG_2BYTE_BOLD )
408                                    ? PFR_NEXT_SHORT( p )
409                                    : PFR_NEXT_BYTE( p );
410 
411       if ( flags & PFR_LOG_EXTRA_ITEMS )
412       {
413         error = pfr_extra_items_skip( &p, limit );
414         if ( error )
415           goto Fail;
416       }
417 
418       PFR_CHECK( 5 );
419       log_font->phys_size   = PFR_NEXT_USHORT( p );
420       log_font->phys_offset = PFR_NEXT_ULONG( p );
421       if ( size_increment )
422       {
423         PFR_CHECK( 1 );
424         log_font->phys_size += (FT_UInt32)PFR_NEXT_BYTE( p ) << 16;
425       }
426     }
427 
428   Fail:
429     FT_FRAME_EXIT();
430 
431   Exit:
432     return error;
433 
434   Too_Short:
435     FT_ERROR(( "pfr_log_font_load: invalid logical font table\n" ));
436     error = FT_THROW( Invalid_Table );
437     goto Fail;
438   }
439 
440 
441   /***********************************************************************/
442   /***********************************************************************/
443   /*****                                                             *****/
444   /*****                    PFR PHYSICAL FONTS                       *****/
445   /*****                                                             *****/
446   /***********************************************************************/
447   /***********************************************************************/
448 
449 
450   /* load bitmap strikes lists */
451   FT_CALLBACK_DEF( FT_Error )
pfr_extra_item_load_bitmap_info(FT_Byte * p,FT_Byte * limit,void * phy_font_)452   pfr_extra_item_load_bitmap_info( FT_Byte*  p,
453                                    FT_Byte*  limit,
454                                    void*     phy_font_ )
455   {
456     PFR_PhyFont  phy_font = (PFR_PhyFont)phy_font_;
457     FT_Memory    memory   = phy_font->memory;
458     PFR_Strike   strike;
459     FT_UInt      flags0;
460     FT_UInt      n, count, size1;
461     FT_Error     error    = FT_Err_Ok;
462 
463 
464     PFR_CHECK( 5 );
465 
466     p     += 3;  /* skip bctSize */
467     flags0 = PFR_NEXT_BYTE( p );
468     count  = PFR_NEXT_BYTE( p );
469 
470     /* re-allocate when needed */
471     if ( phy_font->num_strikes + count > phy_font->max_strikes )
472     {
473       FT_UInt  new_max = FT_PAD_CEIL( phy_font->num_strikes + count, 4 );
474 
475 
476       if ( FT_RENEW_ARRAY( phy_font->strikes,
477                            phy_font->num_strikes,
478                            new_max ) )
479         goto Exit;
480 
481       phy_font->max_strikes = new_max;
482     }
483 
484     size1 = 1 + 1 + 1 + 2 + 2 + 1;
485     if ( flags0 & PFR_STRIKE_2BYTE_XPPM )
486       size1++;
487 
488     if ( flags0 & PFR_STRIKE_2BYTE_YPPM )
489       size1++;
490 
491     if ( flags0 & PFR_STRIKE_3BYTE_SIZE )
492       size1++;
493 
494     if ( flags0 & PFR_STRIKE_3BYTE_OFFSET )
495       size1++;
496 
497     if ( flags0 & PFR_STRIKE_2BYTE_COUNT )
498       size1++;
499 
500     strike = phy_font->strikes + phy_font->num_strikes;
501 
502     PFR_CHECK( count * size1 );
503 
504     for ( n = 0; n < count; n++, strike++ )
505     {
506       strike->x_ppm       = ( flags0 & PFR_STRIKE_2BYTE_XPPM )
507                             ? PFR_NEXT_USHORT( p )
508                             : PFR_NEXT_BYTE( p );
509 
510       strike->y_ppm       = ( flags0 & PFR_STRIKE_2BYTE_YPPM )
511                             ? PFR_NEXT_USHORT( p )
512                             : PFR_NEXT_BYTE( p );
513 
514       strike->flags       = PFR_NEXT_BYTE( p );
515 
516       strike->bct_size    = ( flags0 & PFR_STRIKE_3BYTE_SIZE )
517                             ? PFR_NEXT_ULONG( p )
518                             : PFR_NEXT_USHORT( p );
519 
520       strike->bct_offset  = ( flags0 & PFR_STRIKE_3BYTE_OFFSET )
521                             ? PFR_NEXT_ULONG( p )
522                             : PFR_NEXT_USHORT( p );
523 
524       strike->num_bitmaps = ( flags0 & PFR_STRIKE_2BYTE_COUNT )
525                             ? PFR_NEXT_USHORT( p )
526                             : PFR_NEXT_BYTE( p );
527     }
528 
529     phy_font->num_strikes += count;
530 
531   Exit:
532     return error;
533 
534   Too_Short:
535     error = FT_THROW( Invalid_Table );
536     FT_ERROR(( "pfr_extra_item_load_bitmap_info:"
537                " invalid bitmap info table\n" ));
538     goto Exit;
539   }
540 
541 
542   /* Load font ID.  This is a so-called `unique' name that is rather
543    * long and descriptive (like `Tiresias ScreenFont v7.51').
544    *
545    * Note that a PFR font's family name is contained in an *undocumented*
546    * string of the `auxiliary data' portion of a physical font record.  This
547    * may also contain the `real' style name!
548    *
549    * If no family name is present, the font ID is used instead for the
550    * family.
551    */
552   FT_CALLBACK_DEF( FT_Error )
pfr_extra_item_load_font_id(FT_Byte * p,FT_Byte * limit,void * phy_font_)553   pfr_extra_item_load_font_id( FT_Byte*  p,
554                                FT_Byte*  limit,
555                                void*     phy_font_ )
556   {
557     PFR_PhyFont  phy_font = (PFR_PhyFont)phy_font_;
558     FT_Error     error    = FT_Err_Ok;
559     FT_Memory    memory   = phy_font->memory;
560     FT_UInt      len      = (FT_UInt)( limit - p );
561 
562 
563     if ( phy_font->font_id )
564       goto Exit;
565 
566     if ( FT_QALLOC( phy_font->font_id, len + 1 ) )
567       goto Exit;
568 
569     /* copy font ID name, and terminate it for safety */
570     FT_MEM_COPY( phy_font->font_id, p, len );
571     phy_font->font_id[len] = 0;
572 
573   Exit:
574     return error;
575   }
576 
577 
578   /* load stem snap tables */
579   FT_CALLBACK_DEF( FT_Error )
pfr_extra_item_load_stem_snaps(FT_Byte * p,FT_Byte * limit,void * phy_font_)580   pfr_extra_item_load_stem_snaps( FT_Byte*  p,
581                                   FT_Byte*  limit,
582                                   void*     phy_font_ )
583   {
584     PFR_PhyFont  phy_font = (PFR_PhyFont)phy_font_;
585     FT_UInt      count, num_vert, num_horz;
586     FT_Int*      snaps    = NULL;
587     FT_Error     error    = FT_Err_Ok;
588     FT_Memory    memory   = phy_font->memory;
589 
590 
591     if ( phy_font->vertical.stem_snaps )
592       goto Exit;
593 
594     PFR_CHECK( 1 );
595     count = PFR_NEXT_BYTE( p );
596 
597     num_vert = count & 15;
598     num_horz = count >> 4;
599     count    = num_vert + num_horz;
600 
601     PFR_CHECK( count * 2 );
602 
603     if ( FT_QNEW_ARRAY( snaps, count ) )
604       goto Exit;
605 
606     phy_font->vertical.stem_snaps   = snaps;
607     phy_font->horizontal.stem_snaps = snaps + num_vert;
608 
609     for ( ; count > 0; count--, snaps++ )
610       *snaps = FT_NEXT_SHORT( p );
611 
612   Exit:
613     return error;
614 
615   Too_Short:
616     error = FT_THROW( Invalid_Table );
617     FT_ERROR(( "pfr_extra_item_load_stem_snaps:"
618                " invalid stem snaps table\n" ));
619     goto Exit;
620   }
621 
622 
623   /* load kerning pair data */
624   FT_CALLBACK_DEF( FT_Error )
pfr_extra_item_load_kerning_pairs(FT_Byte * p,FT_Byte * limit,void * phy_font_)625   pfr_extra_item_load_kerning_pairs( FT_Byte*  p,
626                                      FT_Byte*  limit,
627                                      void*     phy_font_ )
628   {
629     PFR_PhyFont  phy_font = (PFR_PhyFont)phy_font_;
630     PFR_KernItem  item   = NULL;
631     FT_Error      error  = FT_Err_Ok;
632     FT_Memory     memory = phy_font->memory;
633 
634 
635     if ( FT_NEW( item ) )
636       goto Exit;
637 
638     PFR_CHECK( 4 );
639 
640     item->pair_count = PFR_NEXT_BYTE( p );
641     item->base_adj   = PFR_NEXT_SHORT( p );
642     item->flags      = PFR_NEXT_BYTE( p );
643     item->offset     = phy_font->offset +
644                        (FT_Offset)( p - phy_font->cursor );
645 
646 #ifndef PFR_CONFIG_NO_CHECKS
647     item->pair_size = 3;
648 
649     if ( item->flags & PFR_KERN_2BYTE_CHAR )
650       item->pair_size += 2;
651 
652     if ( item->flags & PFR_KERN_2BYTE_ADJ )
653       item->pair_size += 1;
654 
655     PFR_CHECK( item->pair_count * item->pair_size );
656 #endif
657 
658     /* load first and last pairs into the item to speed up */
659     /* lookup later...                                     */
660     if ( item->pair_count > 0 )
661     {
662       FT_UInt   char1, char2;
663       FT_Byte*  q;
664 
665 
666       if ( item->flags & PFR_KERN_2BYTE_CHAR )
667       {
668         q     = p;
669         char1 = PFR_NEXT_USHORT( q );
670         char2 = PFR_NEXT_USHORT( q );
671 
672         item->pair1 = PFR_KERN_INDEX( char1, char2 );
673 
674         q = p + item->pair_size * ( item->pair_count - 1 );
675         char1 = PFR_NEXT_USHORT( q );
676         char2 = PFR_NEXT_USHORT( q );
677 
678         item->pair2 = PFR_KERN_INDEX( char1, char2 );
679       }
680       else
681       {
682         q     = p;
683         char1 = PFR_NEXT_BYTE( q );
684         char2 = PFR_NEXT_BYTE( q );
685 
686         item->pair1 = PFR_KERN_INDEX( char1, char2 );
687 
688         q = p + item->pair_size * ( item->pair_count - 1 );
689         char1 = PFR_NEXT_BYTE( q );
690         char2 = PFR_NEXT_BYTE( q );
691 
692         item->pair2 = PFR_KERN_INDEX( char1, char2 );
693       }
694 
695       /* add new item to the current list */
696       item->next                 = NULL;
697       *phy_font->kern_items_tail = item;
698       phy_font->kern_items_tail  = &item->next;
699       phy_font->num_kern_pairs  += item->pair_count;
700     }
701     else
702     {
703       /* empty item! */
704       FT_FREE( item );
705     }
706 
707   Exit:
708     return error;
709 
710   Too_Short:
711     FT_FREE( item );
712 
713     error = FT_THROW( Invalid_Table );
714     FT_ERROR(( "pfr_extra_item_load_kerning_pairs:"
715                " invalid kerning pairs table\n" ));
716     goto Exit;
717   }
718 
719 
720   static const PFR_ExtraItemRec  pfr_phy_font_extra_items[] =
721   {
722     { 1, pfr_extra_item_load_bitmap_info },
723     { 2, pfr_extra_item_load_font_id },
724     { 3, pfr_extra_item_load_stem_snaps },
725     { 4, pfr_extra_item_load_kerning_pairs },
726     { 0, NULL }
727   };
728 
729 
730   /*
731    * Load a name from the auxiliary data.  Since this extracts undocumented
732    * strings from the font file, we need to be careful here.
733    */
734   static FT_Error
pfr_aux_name_load(FT_Byte * p,FT_UInt len,FT_Memory memory,FT_String ** astring)735   pfr_aux_name_load( FT_Byte*     p,
736                      FT_UInt      len,
737                      FT_Memory    memory,
738                      FT_String*  *astring )
739   {
740     FT_Error    error  = FT_Err_Ok;
741     FT_String*  result = NULL;
742     FT_UInt     n, ok;
743 
744 
745     if ( *astring )
746       FT_FREE( *astring );
747 
748     if ( len > 0 && p[len - 1] == 0 )
749       len--;
750 
751     /* check that each character is ASCII  */
752     /* for making sure not to load garbage */
753     ok = ( len > 0 );
754     for ( n = 0; n < len; n++ )
755       if ( p[n] < 32 || p[n] > 127 )
756       {
757         ok = 0;
758         break;
759       }
760 
761     if ( ok )
762     {
763       if ( FT_QALLOC( result, len + 1 ) )
764         goto Exit;
765 
766       FT_MEM_COPY( result, p, len );
767       result[len] = 0;
768     }
769 
770   Exit:
771     *astring = result;
772     return error;
773   }
774 
775 
776   FT_LOCAL_DEF( void )
pfr_phy_font_done(PFR_PhyFont phy_font,FT_Memory memory)777   pfr_phy_font_done( PFR_PhyFont  phy_font,
778                      FT_Memory    memory )
779   {
780     FT_FREE( phy_font->font_id );
781     FT_FREE( phy_font->family_name );
782     FT_FREE( phy_font->style_name );
783 
784     FT_FREE( phy_font->vertical.stem_snaps );
785     phy_font->vertical.num_stem_snaps = 0;
786 
787     phy_font->horizontal.stem_snaps     = NULL;
788     phy_font->horizontal.num_stem_snaps = 0;
789 
790     FT_FREE( phy_font->strikes );
791     phy_font->num_strikes = 0;
792     phy_font->max_strikes = 0;
793 
794     FT_FREE( phy_font->chars );
795     phy_font->num_chars    = 0;
796     phy_font->chars_offset = 0;
797 
798     FT_FREE( phy_font->blue_values );
799     phy_font->num_blue_values = 0;
800 
801     {
802       PFR_KernItem  item, next;
803 
804 
805       item = phy_font->kern_items;
806       while ( item )
807       {
808         next = item->next;
809         FT_FREE( item );
810         item = next;
811       }
812       phy_font->kern_items      = NULL;
813       phy_font->kern_items_tail = NULL;
814     }
815 
816     phy_font->num_kern_pairs = 0;
817   }
818 
819 
820   FT_LOCAL_DEF( FT_Error )
pfr_phy_font_load(PFR_PhyFont phy_font,FT_Stream stream,FT_UInt32 offset,FT_UInt32 size)821   pfr_phy_font_load( PFR_PhyFont  phy_font,
822                      FT_Stream    stream,
823                      FT_UInt32    offset,
824                      FT_UInt32    size )
825   {
826     FT_Error   error;
827     FT_Memory  memory = stream->memory;
828     FT_UInt    flags;
829     FT_ULong   num_aux;
830     FT_Byte*   p;
831     FT_Byte*   limit;
832 
833 
834     phy_font->memory = memory;
835     phy_font->offset = offset;
836 
837     phy_font->kern_items      = NULL;
838     phy_font->kern_items_tail = &phy_font->kern_items;
839 
840     if ( FT_STREAM_SEEK( offset ) ||
841          FT_FRAME_ENTER( size )   )
842       goto Exit;
843 
844     phy_font->cursor = stream->cursor;
845 
846     p     = stream->cursor;
847     limit = p + size;
848 
849     PFR_CHECK( 15 );
850     phy_font->font_ref_number    = PFR_NEXT_USHORT( p );
851     phy_font->outline_resolution = PFR_NEXT_USHORT( p );
852     phy_font->metrics_resolution = PFR_NEXT_USHORT( p );
853     phy_font->bbox.xMin          = PFR_NEXT_SHORT( p );
854     phy_font->bbox.yMin          = PFR_NEXT_SHORT( p );
855     phy_font->bbox.xMax          = PFR_NEXT_SHORT( p );
856     phy_font->bbox.yMax          = PFR_NEXT_SHORT( p );
857     phy_font->flags      = flags = PFR_NEXT_BYTE( p );
858 
859     if ( !phy_font->outline_resolution ||
860          !phy_font->metrics_resolution )
861     {
862       error = FT_THROW( Invalid_Table );
863       FT_ERROR(( "pfr_phy_font_load: invalid resolution\n" ));
864       goto Fail;
865     }
866 
867     /* get the standard advance for non-proportional fonts */
868     if ( !( flags & PFR_PHY_PROPORTIONAL ) )
869     {
870       PFR_CHECK( 2 );
871       phy_font->standard_advance = PFR_NEXT_SHORT( p );
872     }
873 
874     /* load the extra items when present */
875     if ( flags & PFR_PHY_EXTRA_ITEMS )
876     {
877       error = pfr_extra_items_parse( &p, limit,
878                                      pfr_phy_font_extra_items, phy_font );
879       if ( error )
880         goto Fail;
881     }
882 
883     /* In certain fonts, the auxiliary bytes contain interesting   */
884     /* information.  These are not in the specification but can be */
885     /* guessed by looking at the content of a few 'PFR0' fonts.    */
886     PFR_CHECK( 3 );
887     num_aux = PFR_NEXT_ULONG( p );
888 
889     if ( num_aux > 0 )
890     {
891       FT_Byte*  q = p;
892       FT_Byte*  q2;
893 
894 
895       PFR_CHECK_SIZE( num_aux );
896       p += num_aux;
897 
898       while ( num_aux > 0 )
899       {
900         FT_UInt  length, type;
901 
902 
903         if ( q + 4 > p )
904           break;
905 
906         length = PFR_NEXT_USHORT( q );
907         if ( length < 4 || length > num_aux )
908           break;
909 
910         q2   = q + length - 2;
911         type = PFR_NEXT_USHORT( q );
912 
913         switch ( type )
914         {
915         case 1:
916           /* this seems to correspond to the font's family name, padded to */
917           /* an even number of bytes with a zero byte appended if needed   */
918           error = pfr_aux_name_load( q, length - 4U, memory,
919                                      &phy_font->family_name );
920           if ( error )
921             goto Exit;
922           break;
923 
924         case 2:
925           if ( q + 32 > q2 )
926             break;
927 
928           q += 10;
929           phy_font->ascent  = PFR_NEXT_SHORT( q );
930           phy_font->descent = PFR_NEXT_SHORT( q );
931           phy_font->leading = PFR_NEXT_SHORT( q );
932           break;
933 
934         case 3:
935           /* this seems to correspond to the font's style name, padded to */
936           /* an even number of bytes with a zero byte appended if needed  */
937           error = pfr_aux_name_load( q, length - 4U, memory,
938                                      &phy_font->style_name );
939           if ( error )
940             goto Exit;
941           break;
942 
943         default:
944           ;
945         }
946 
947         q        = q2;
948         num_aux -= length;
949       }
950     }
951 
952     /* read the blue values */
953     {
954       FT_UInt  n, count;
955 
956 
957       PFR_CHECK( 1 );
958       phy_font->num_blue_values = count = PFR_NEXT_BYTE( p );
959 
960       PFR_CHECK( count * 2 );
961 
962       if ( FT_QNEW_ARRAY( phy_font->blue_values, count ) )
963         goto Fail;
964 
965       for ( n = 0; n < count; n++ )
966         phy_font->blue_values[n] = PFR_NEXT_SHORT( p );
967     }
968 
969     PFR_CHECK( 8 );
970     phy_font->blue_fuzz  = PFR_NEXT_BYTE( p );
971     phy_font->blue_scale = PFR_NEXT_BYTE( p );
972 
973     phy_font->vertical.standard   = PFR_NEXT_USHORT( p );
974     phy_font->horizontal.standard = PFR_NEXT_USHORT( p );
975 
976     /* read the character descriptors */
977     {
978       FT_UInt  n, count, Size;
979 
980 
981       phy_font->num_chars    = count = PFR_NEXT_USHORT( p );
982       phy_font->chars_offset = offset + (FT_Offset)( p - stream->cursor );
983 
984       if ( !phy_font->num_chars )
985       {
986         error = FT_THROW( Invalid_Table );
987         FT_ERROR(( "pfr_phy_font_load: no glyphs\n" ));
988         goto Fail;
989       }
990 
991       Size = 1 + 1 + 2;
992       if ( flags & PFR_PHY_2BYTE_CHARCODE )
993         Size += 1;
994 
995       if ( flags & PFR_PHY_PROPORTIONAL )
996         Size += 2;
997 
998       if ( flags & PFR_PHY_ASCII_CODE )
999         Size += 1;
1000 
1001       if ( flags & PFR_PHY_2BYTE_GPS_SIZE )
1002         Size += 1;
1003 
1004       if ( flags & PFR_PHY_3BYTE_GPS_OFFSET )
1005         Size += 1;
1006 
1007       PFR_CHECK_SIZE( count * Size );
1008 
1009       if ( FT_QNEW_ARRAY( phy_font->chars, count ) )
1010         goto Fail;
1011 
1012       for ( n = 0; n < count; n++ )
1013       {
1014         PFR_Char  cur = &phy_font->chars[n];
1015 
1016 
1017         cur->char_code = ( flags & PFR_PHY_2BYTE_CHARCODE )
1018                          ? PFR_NEXT_USHORT( p )
1019                          : PFR_NEXT_BYTE( p );
1020 
1021         cur->advance   = ( flags & PFR_PHY_PROPORTIONAL )
1022                          ? PFR_NEXT_SHORT( p )
1023                          : phy_font->standard_advance;
1024 
1025 #if 0
1026         cur->ascii     = ( flags & PFR_PHY_ASCII_CODE )
1027                          ? PFR_NEXT_BYTE( p )
1028                          : 0;
1029 #else
1030         if ( flags & PFR_PHY_ASCII_CODE )
1031           p += 1;
1032 #endif
1033         cur->gps_size  = ( flags & PFR_PHY_2BYTE_GPS_SIZE )
1034                          ? PFR_NEXT_USHORT( p )
1035                          : PFR_NEXT_BYTE( p );
1036 
1037         cur->gps_offset = ( flags & PFR_PHY_3BYTE_GPS_OFFSET )
1038                           ? PFR_NEXT_ULONG( p )
1039                           : PFR_NEXT_USHORT( p );
1040       }
1041     }
1042 
1043     /* that's it! */
1044 
1045   Fail:
1046     FT_FRAME_EXIT();
1047 
1048     /* save position of bitmap info */
1049     phy_font->bct_offset = FT_STREAM_POS();
1050     phy_font->cursor     = NULL;
1051 
1052   Exit:
1053     return error;
1054 
1055   Too_Short:
1056     error = FT_THROW( Invalid_Table );
1057     FT_ERROR(( "pfr_phy_font_load: invalid physical font table\n" ));
1058     goto Fail;
1059   }
1060 
1061 
1062 /* END */
1063