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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  )
     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 )
    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
    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: `head' table too small\n" ));
    240           error = FT_THROW( Table_Missing );
    241           goto Exit;
    242         }
    243 
    244         if ( FT_STREAM_SEEK( table.Offset + 12 ) ||
    245              FT_READ_ULONG( magic )              )
    246           goto Exit;
    247 
    248         if ( magic != 0x5F0F3CF5UL )
    249         {
    250           FT_TRACE2(( "check_table_dir:"
    251                       " no magic number found in `head' table\n"));
    252           error = FT_THROW( Table_Missing );
    253           goto Exit;
    254         }
    255 
    256         if ( FT_STREAM_SEEK( offset + ( nn + 1 ) * 16 ) )
    257           goto Exit;
    258       }
    259       else if ( table.Tag == TTAG_SING )
    260         has_sing = 1;
    261       else if ( table.Tag == TTAG_META )
    262         has_meta = 1;
    263     }
    264 
    265     sfnt->num_tables = valid_entries;
    266 
    267     if ( sfnt->num_tables == 0 )
    268     {
    269       FT_TRACE2(( "check_table_dir: no tables found\n" ));
    270       error = FT_THROW( Unknown_File_Format );
    271       goto Exit;
    272     }
    273 
    274     /* if `sing' and `meta' tables are present, there is no `head' table */
    275     if ( has_head || ( has_sing && has_meta ) )
    276     {
    277       error = FT_Err_Ok;
    278       goto Exit;
    279     }
    280     else
    281     {
    282       FT_TRACE2(( "check_table_dir:" ));
    283 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
    284       FT_TRACE2(( " neither `head', `bhed', nor `sing' table found\n" ));
    285 #else
    286       FT_TRACE2(( " neither `head' nor `sing' table found\n" ));
    287 #endif
    288       error = FT_THROW( Table_Missing );
    289     }
    290 
    291   Exit:
    292     return error;
    293   }
    294 
    295 
    296   /*************************************************************************/
    297   /*                                                                       */
    298   /* <Function>                                                            */
    299   /*    tt_face_load_font_dir                                              */
    300   /*                                                                       */
    301   /* <Description>                                                         */
    302   /*    Loads the header of a SFNT font file.                              */
    303   /*                                                                       */
    304   /* <Input>                                                               */
    305   /*    face       :: A handle to the target face object.                  */
    306   /*                                                                       */
    307   /*    stream     :: The input stream.                                    */
    308   /*                                                                       */
    309   /* <Output>                                                              */
    310   /*    sfnt       :: The SFNT header.                                     */
    311   /*                                                                       */
    312   /* <Return>                                                              */
    313   /*    FreeType error code.  0 means success.                             */
    314   /*                                                                       */
    315   /* <Note>                                                                */
    316   /*    The stream cursor must be at the beginning of the font directory.  */
    317   /*                                                                       */
    318   FT_LOCAL_DEF( FT_Error )
    319   tt_face_load_font_dir( TT_Face    face,
    320                          FT_Stream  stream )
    321   {
    322     SFNT_HeaderRec  sfnt;
    323     FT_Error        error;
    324     FT_Memory       memory = stream->memory;
    325     TT_TableRec*    entry;
    326     FT_Int          nn;
    327 
    328     static const FT_Frame_Field  offset_table_fields[] =
    329     {
    330 #undef  FT_STRUCTURE
    331 #define FT_STRUCTURE  SFNT_HeaderRec
    332 
    333       FT_FRAME_START( 8 ),
    334         FT_FRAME_USHORT( num_tables ),
    335         FT_FRAME_USHORT( search_range ),
    336         FT_FRAME_USHORT( entry_selector ),
    337         FT_FRAME_USHORT( range_shift ),
    338       FT_FRAME_END
    339     };
    340 
    341 
    342     FT_TRACE2(( "tt_face_load_font_dir: %08p\n", face ));
    343 
    344     /* read the offset table */
    345 
    346     sfnt.offset = FT_STREAM_POS();
    347 
    348     if ( FT_READ_ULONG( sfnt.format_tag )                    ||
    349          FT_STREAM_READ_FIELDS( offset_table_fields, &sfnt ) )
    350       goto Exit;
    351 
    352     /* many fonts don't have these fields set correctly */
    353 #if 0
    354     if ( sfnt.search_range != 1 << ( sfnt.entry_selector + 4 )        ||
    355          sfnt.search_range + sfnt.range_shift != sfnt.num_tables << 4 )
    356       return FT_THROW( Unknown_File_Format );
    357 #endif
    358 
    359     /* load the table directory */
    360 
    361     FT_TRACE2(( "-- Number of tables: %10u\n",    sfnt.num_tables ));
    362     FT_TRACE2(( "-- Format version:   0x%08lx\n", sfnt.format_tag ));
    363 
    364     if ( sfnt.format_tag != TTAG_OTTO )
    365     {
    366       /* check first */
    367       error = check_table_dir( &sfnt, stream );
    368       if ( error )
    369       {
    370         FT_TRACE2(( "tt_face_load_font_dir:"
    371                     " invalid table directory for TrueType\n" ));
    372 
    373         goto Exit;
    374       }
    375     }
    376 
    377     face->num_tables = sfnt.num_tables;
    378     face->format_tag = sfnt.format_tag;
    379 
    380     if ( FT_QNEW_ARRAY( face->dir_tables, face->num_tables ) )
    381       goto Exit;
    382 
    383     if ( FT_STREAM_SEEK( sfnt.offset + 12 )       ||
    384          FT_FRAME_ENTER( face->num_tables * 16L ) )
    385       goto Exit;
    386 
    387     entry = face->dir_tables;
    388 
    389     FT_TRACE2(( "\n"
    390                 "  tag    offset    length   checksum\n"
    391                 "  ----------------------------------\n" ));
    392 
    393     for ( nn = 0; nn < sfnt.num_tables; nn++ )
    394     {
    395       entry->Tag      = FT_GET_TAG4();
    396       entry->CheckSum = FT_GET_ULONG();
    397       entry->Offset   = FT_GET_LONG();
    398       entry->Length   = FT_GET_LONG();
    399 
    400       /* ignore invalid tables */
    401       if ( entry->Offset + entry->Length > stream->size )
    402         continue;
    403       else
    404       {
    405         FT_TRACE2(( "  %c%c%c%c  %08lx  %08lx  %08lx\n",
    406                     (FT_Char)( entry->Tag >> 24 ),
    407                     (FT_Char)( entry->Tag >> 16 ),
    408                     (FT_Char)( entry->Tag >> 8  ),
    409                     (FT_Char)( entry->Tag       ),
    410                     entry->Offset,
    411                     entry->Length,
    412                     entry->CheckSum ));
    413         entry++;
    414       }
    415     }
    416 
    417     FT_FRAME_EXIT();
    418 
    419     FT_TRACE2(( "table directory loaded\n\n" ));
    420 
    421   Exit:
    422     return error;
    423   }
    424 
    425 
    426   /*************************************************************************/
    427   /*                                                                       */
    428   /* <Function>                                                            */
    429   /*    tt_face_load_any                                                   */
    430   /*                                                                       */
    431   /* <Description>                                                         */
    432   /*    Loads any font table into client memory.                           */
    433   /*                                                                       */
    434   /* <Input>                                                               */
    435   /*    face   :: The face object to look for.                             */
    436   /*                                                                       */
    437   /*    tag    :: The tag of table to load.  Use the value 0 if you want   */
    438   /*              to access the whole font file, else set this parameter   */
    439   /*              to a valid TrueType table tag that you can forge with    */
    440   /*              the MAKE_TT_TAG macro.                                   */
    441   /*                                                                       */
    442   /*    offset :: The starting offset in the table (or the file if         */
    443   /*              tag == 0).                                               */
    444   /*                                                                       */
    445   /*    length :: The address of the decision variable:                    */
    446   /*                                                                       */
    447   /*                If length == NULL:                                     */
    448   /*                  Loads the whole table.  Returns an error if          */
    449   /*                  `offset' == 0!                                       */
    450   /*                                                                       */
    451   /*                If *length == 0:                                       */
    452   /*                  Exits immediately; returning the length of the given */
    453   /*                  table or of the font file, depending on the value of */
    454   /*                  `tag'.                                               */
    455   /*                                                                       */
    456   /*                If *length != 0:                                       */
    457   /*                  Loads the next `length' bytes of table or font,      */
    458   /*                  starting at offset `offset' (in table or font too).  */
    459   /*                                                                       */
    460   /* <Output>                                                              */
    461   /*    buffer :: The address of target buffer.                            */
    462   /*                                                                       */
    463   /* <Return>                                                              */
    464   /*    FreeType error code.  0 means success.                             */
    465   /*                                                                       */
    466   FT_LOCAL_DEF( FT_Error )
    467   tt_face_load_any( TT_Face    face,
    468                     FT_ULong   tag,
    469                     FT_Long    offset,
    470                     FT_Byte*   buffer,
    471                     FT_ULong*  length )
    472   {
    473     FT_Error   error;
    474     FT_Stream  stream;
    475     TT_Table   table;
    476     FT_ULong   size;
    477 
    478 
    479     if ( tag != 0 )
    480     {
    481       /* look for tag in font directory */
    482       table = tt_face_lookup_table( face, tag );
    483       if ( !table )
    484       {
    485         error = FT_THROW( Table_Missing );
    486         goto Exit;
    487       }
    488 
    489       offset += table->Offset;
    490       size    = table->Length;
    491     }
    492     else
    493       /* tag == 0 -- the user wants to access the font file directly */
    494       size = face->root.stream->size;
    495 
    496     if ( length && *length == 0 )
    497     {
    498       *length = size;
    499 
    500       return FT_Err_Ok;
    501     }
    502 
    503     if ( length )
    504       size = *length;
    505 
    506     stream = face->root.stream;
    507     /* the `if' is syntactic sugar for picky compilers */
    508     if ( FT_STREAM_READ_AT( offset, buffer, size ) )
    509       goto Exit;
    510 
    511   Exit:
    512     return error;
    513   }
    514 
    515 
    516   /*************************************************************************/
    517   /*                                                                       */
    518   /* <Function>                                                            */
    519   /*    tt_face_load_generic_header                                        */
    520   /*                                                                       */
    521   /* <Description>                                                         */
    522   /*    Loads the TrueType table `head' or `bhed'.                         */
    523   /*                                                                       */
    524   /* <Input>                                                               */
    525   /*    face   :: A handle to the target face object.                      */
    526   /*                                                                       */
    527   /*    stream :: The input stream.                                        */
    528   /*                                                                       */
    529   /* <Return>                                                              */
    530   /*    FreeType error code.  0 means success.                             */
    531   /*                                                                       */
    532   static FT_Error
    533   tt_face_load_generic_header( TT_Face    face,
    534                                FT_Stream  stream,
    535                                FT_ULong   tag )
    536   {
    537     FT_Error    error;
    538     TT_Header*  header;
    539 
    540     static const FT_Frame_Field  header_fields[] =
    541     {
    542 #undef  FT_STRUCTURE
    543 #define FT_STRUCTURE  TT_Header
    544 
    545       FT_FRAME_START( 54 ),
    546         FT_FRAME_ULONG ( Table_Version ),
    547         FT_FRAME_ULONG ( Font_Revision ),
    548         FT_FRAME_LONG  ( CheckSum_Adjust ),
    549         FT_FRAME_LONG  ( Magic_Number ),
    550         FT_FRAME_USHORT( Flags ),
    551         FT_FRAME_USHORT( Units_Per_EM ),
    552         FT_FRAME_LONG  ( Created[0] ),
    553         FT_FRAME_LONG  ( Created[1] ),
    554         FT_FRAME_LONG  ( Modified[0] ),
    555         FT_FRAME_LONG  ( Modified[1] ),
    556         FT_FRAME_SHORT ( xMin ),
    557         FT_FRAME_SHORT ( yMin ),
    558         FT_FRAME_SHORT ( xMax ),
    559         FT_FRAME_SHORT ( yMax ),
    560         FT_FRAME_USHORT( Mac_Style ),
    561         FT_FRAME_USHORT( Lowest_Rec_PPEM ),
    562         FT_FRAME_SHORT ( Font_Direction ),
    563         FT_FRAME_SHORT ( Index_To_Loc_Format ),
    564         FT_FRAME_SHORT ( Glyph_Data_Format ),
    565       FT_FRAME_END
    566     };
    567 
    568 
    569     error = face->goto_table( face, tag, stream, 0 );
    570     if ( error )
    571       goto Exit;
    572 
    573     header = &face->header;
    574 
    575     if ( FT_STREAM_READ_FIELDS( header_fields, header ) )
    576       goto Exit;
    577 
    578     FT_TRACE3(( "Units per EM: %4u\n", header->Units_Per_EM ));
    579     FT_TRACE3(( "IndexToLoc:   %4d\n", header->Index_To_Loc_Format ));
    580 
    581   Exit:
    582     return error;
    583   }
    584 
    585 
    586   FT_LOCAL_DEF( FT_Error )
    587   tt_face_load_head( TT_Face    face,
    588                      FT_Stream  stream )
    589   {
    590     return tt_face_load_generic_header( face, stream, TTAG_head );
    591   }
    592 
    593 
    594 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
    595 
    596   FT_LOCAL_DEF( FT_Error )
    597   tt_face_load_bhed( TT_Face    face,
    598                      FT_Stream  stream )
    599   {
    600     return tt_face_load_generic_header( face, stream, TTAG_bhed );
    601   }
    602 
    603 #endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */
    604 
    605 
    606   /*************************************************************************/
    607   /*                                                                       */
    608   /* <Function>                                                            */
    609   /*    tt_face_load_max_profile                                           */
    610   /*                                                                       */
    611   /* <Description>                                                         */
    612   /*    Loads the maximum profile into a face object.                      */
    613   /*                                                                       */
    614   /* <Input>                                                               */
    615   /*    face   :: A handle to the target face object.                      */
    616   /*                                                                       */
    617   /*    stream :: The input stream.                                        */
    618   /*                                                                       */
    619   /* <Return>                                                              */
    620   /*    FreeType error code.  0 means success.                             */
    621   /*                                                                       */
    622   FT_LOCAL_DEF( FT_Error )
    623   tt_face_load_maxp( TT_Face    face,
    624                      FT_Stream  stream )
    625   {
    626     FT_Error        error;
    627     TT_MaxProfile*  maxProfile = &face->max_profile;
    628 
    629     static const FT_Frame_Field  maxp_fields[] =
    630     {
    631 #undef  FT_STRUCTURE
    632 #define FT_STRUCTURE  TT_MaxProfile
    633 
    634       FT_FRAME_START( 6 ),
    635         FT_FRAME_LONG  ( version ),
    636         FT_FRAME_USHORT( numGlyphs ),
    637       FT_FRAME_END
    638     };
    639 
    640     static const FT_Frame_Field  maxp_fields_extra[] =
    641     {
    642       FT_FRAME_START( 26 ),
    643         FT_FRAME_USHORT( maxPoints ),
    644         FT_FRAME_USHORT( maxContours ),
    645         FT_FRAME_USHORT( maxCompositePoints ),
    646         FT_FRAME_USHORT( maxCompositeContours ),
    647         FT_FRAME_USHORT( maxZones ),
    648         FT_FRAME_USHORT( maxTwilightPoints ),
    649         FT_FRAME_USHORT( maxStorage ),
    650         FT_FRAME_USHORT( maxFunctionDefs ),
    651         FT_FRAME_USHORT( maxInstructionDefs ),
    652         FT_FRAME_USHORT( maxStackElements ),
    653         FT_FRAME_USHORT( maxSizeOfInstructions ),
    654         FT_FRAME_USHORT( maxComponentElements ),
    655         FT_FRAME_USHORT( maxComponentDepth ),
    656       FT_FRAME_END
    657     };
    658 
    659 
    660     error = face->goto_table( face, TTAG_maxp, stream, 0 );
    661     if ( error )
    662       goto Exit;
    663 
    664     if ( FT_STREAM_READ_FIELDS( maxp_fields, maxProfile ) )
    665       goto Exit;
    666 
    667     maxProfile->maxPoints             = 0;
    668     maxProfile->maxContours           = 0;
    669     maxProfile->maxCompositePoints    = 0;
    670     maxProfile->maxCompositeContours  = 0;
    671     maxProfile->maxZones              = 0;
    672     maxProfile->maxTwilightPoints     = 0;
    673     maxProfile->maxStorage            = 0;
    674     maxProfile->maxFunctionDefs       = 0;
    675     maxProfile->maxInstructionDefs    = 0;
    676     maxProfile->maxStackElements      = 0;
    677     maxProfile->maxSizeOfInstructions = 0;
    678     maxProfile->maxComponentElements  = 0;
    679     maxProfile->maxComponentDepth     = 0;
    680 
    681     if ( maxProfile->version >= 0x10000L )
    682     {
    683       if ( FT_STREAM_READ_FIELDS( maxp_fields_extra, maxProfile ) )
    684         goto Exit;
    685 
    686       /* XXX: an adjustment that is necessary to load certain */
    687       /*      broken fonts like `Keystrokes MT' :-(           */
    688       /*                                                      */
    689       /*   We allocate 64 function entries by default when    */
    690       /*   the maxFunctionDefs value is smaller.              */
    691 
    692       if ( maxProfile->maxFunctionDefs < 64 )
    693         maxProfile->maxFunctionDefs = 64;
    694 
    695       /* we add 4 phantom points later */
    696       if ( maxProfile->maxTwilightPoints > ( 0xFFFFU - 4 ) )
    697       {
    698         FT_TRACE0(( "tt_face_load_maxp:"
    699                     " too much twilight points in `maxp' table;\n"
    700                     "                  "
    701                     " some glyphs might be rendered incorrectly\n" ));
    702 
    703         maxProfile->maxTwilightPoints = 0xFFFFU - 4;
    704       }
    705 
    706       /* we arbitrarily limit recursion to avoid stack exhaustion */
    707       if ( maxProfile->maxComponentDepth > 100 )
    708       {
    709         FT_TRACE0(( "tt_face_load_maxp:"
    710                     " abnormally large component depth (%d) set to 100\n",
    711                     maxProfile->maxComponentDepth ));
    712         maxProfile->maxComponentDepth = 100;
    713       }
    714     }
    715 
    716     FT_TRACE3(( "numGlyphs: %u\n", maxProfile->numGlyphs ));
    717 
    718   Exit:
    719     return error;
    720   }
    721 
    722 
    723   /*************************************************************************/
    724   /*                                                                       */
    725   /* <Function>                                                            */
    726   /*    tt_face_load_name                                                  */
    727   /*                                                                       */
    728   /* <Description>                                                         */
    729   /*    Loads the name records.                                            */
    730   /*                                                                       */
    731   /* <Input>                                                               */
    732   /*    face   :: A handle to the target face object.                      */
    733   /*                                                                       */
    734   /*    stream :: The input stream.                                        */
    735   /*                                                                       */
    736   /* <Return>                                                              */
    737   /*    FreeType error code.  0 means success.                             */
    738   /*                                                                       */
    739   FT_LOCAL_DEF( FT_Error )
    740   tt_face_load_name( TT_Face    face,
    741                      FT_Stream  stream )
    742   {
    743     FT_Error      error;
    744     FT_Memory     memory = stream->memory;
    745     FT_ULong      table_pos, table_len;
    746     FT_ULong      storage_start, storage_limit;
    747     FT_UInt       count;
    748     TT_NameTable  table;
    749 
    750     static const FT_Frame_Field  name_table_fields[] =
    751     {
    752 #undef  FT_STRUCTURE
    753 #define FT_STRUCTURE  TT_NameTableRec
    754 
    755       FT_FRAME_START( 6 ),
    756         FT_FRAME_USHORT( format ),
    757         FT_FRAME_USHORT( numNameRecords ),
    758         FT_FRAME_USHORT( storageOffset ),
    759       FT_FRAME_END
    760     };
    761 
    762     static const FT_Frame_Field  name_record_fields[] =
    763     {
    764 #undef  FT_STRUCTURE
    765 #define FT_STRUCTURE  TT_NameEntryRec
    766 
    767       /* no FT_FRAME_START */
    768         FT_FRAME_USHORT( platformID ),
    769         FT_FRAME_USHORT( encodingID ),
    770         FT_FRAME_USHORT( languageID ),
    771         FT_FRAME_USHORT( nameID ),
    772         FT_FRAME_USHORT( stringLength ),
    773         FT_FRAME_USHORT( stringOffset ),
    774       FT_FRAME_END
    775     };
    776 
    777 
    778     table         = &face->name_table;
    779     table->stream = stream;
    780 
    781     error = face->goto_table( face, TTAG_name, stream, &table_len );
    782     if ( error )
    783       goto Exit;
    784 
    785     table_pos = FT_STREAM_POS();
    786 
    787 
    788     if ( FT_STREAM_READ_FIELDS( name_table_fields, table ) )
    789       goto Exit;
    790 
    791     /* Some popular Asian fonts have an invalid `storageOffset' value   */
    792     /* (it should be at least "6 + 12*num_names").  However, the string */
    793     /* offsets, computed as "storageOffset + entry->stringOffset", are  */
    794     /* valid pointers within the name table...                          */
    795     /*                                                                  */
    796     /* We thus can't check `storageOffset' right now.                   */
    797     /*                                                                  */
    798     storage_start = table_pos + 6 + 12*table->numNameRecords;
    799     storage_limit = table_pos + table_len;
    800 
    801     if ( storage_start > storage_limit )
    802     {
    803       FT_ERROR(( "tt_face_load_name: invalid `name' table\n" ));
    804       error = FT_THROW( Name_Table_Missing );
    805       goto Exit;
    806     }
    807 
    808     /* Allocate the array of name records. */
    809     count                 = table->numNameRecords;
    810     table->numNameRecords = 0;
    811 
    812     if ( FT_NEW_ARRAY( table->names, count ) ||
    813          FT_FRAME_ENTER( count * 12 )        )
    814       goto Exit;
    815 
    816     /* Load the name records and determine how much storage is needed */
    817     /* to hold the strings themselves.                                */
    818     {
    819       TT_NameEntryRec*  entry = table->names;
    820 
    821 
    822       for ( ; count > 0; count-- )
    823       {
    824         if ( FT_STREAM_READ_FIELDS( name_record_fields, entry ) )
    825           continue;
    826 
    827         /* check that the name is not empty */
    828         if ( entry->stringLength == 0 )
    829           continue;
    830 
    831         /* check that the name string is within the table */
    832         entry->stringOffset += table_pos + table->storageOffset;
    833         if ( entry->stringOffset                       < storage_start ||
    834              entry->stringOffset + entry->stringLength > storage_limit )
    835         {
    836           /* invalid entry - ignore it */
    837           entry->stringOffset = 0;
    838           entry->stringLength = 0;
    839           continue;
    840         }
    841 
    842         entry++;
    843       }
    844 
    845       table->numNameRecords = (FT_UInt)( entry - table->names );
    846     }
    847 
    848     FT_FRAME_EXIT();
    849 
    850     /* everything went well, update face->num_names */
    851     face->num_names = (FT_UShort) table->numNameRecords;
    852 
    853   Exit:
    854     return error;
    855   }
    856 
    857 
    858   /*************************************************************************/
    859   /*                                                                       */
    860   /* <Function>                                                            */
    861   /*    tt_face_free_names                                                 */
    862   /*                                                                       */
    863   /* <Description>                                                         */
    864   /*    Frees the name records.                                            */
    865   /*                                                                       */
    866   /* <Input>                                                               */
    867   /*    face :: A handle to the target face object.                        */
    868   /*                                                                       */
    869   FT_LOCAL_DEF( void )
    870   tt_face_free_name( TT_Face  face )
    871   {
    872     FT_Memory     memory = face->root.driver->root.memory;
    873     TT_NameTable  table  = &face->name_table;
    874     TT_NameEntry  entry  = table->names;
    875     FT_UInt       count  = table->numNameRecords;
    876 
    877 
    878     if ( table->names )
    879     {
    880       for ( ; count > 0; count--, entry++ )
    881       {
    882         FT_FREE( entry->string );
    883         entry->stringLength = 0;
    884       }
    885 
    886       /* free strings table */
    887       FT_FREE( table->names );
    888     }
    889 
    890     table->numNameRecords = 0;
    891     table->format         = 0;
    892     table->storageOffset  = 0;
    893   }
    894 
    895 
    896   /*************************************************************************/
    897   /*                                                                       */
    898   /* <Function>                                                            */
    899   /*    tt_face_load_cmap                                                  */
    900   /*                                                                       */
    901   /* <Description>                                                         */
    902   /*    Loads the cmap directory in a face object.  The cmaps themselves   */
    903   /*    are loaded on demand in the `ttcmap.c' module.                     */
    904   /*                                                                       */
    905   /* <Input>                                                               */
    906   /*    face   :: A handle to the target face object.                      */
    907   /*                                                                       */
    908   /*    stream :: A handle to the input stream.                            */
    909   /*                                                                       */
    910   /* <Return>                                                              */
    911   /*    FreeType error code.  0 means success.                             */
    912   /*                                                                       */
    913 
    914   FT_LOCAL_DEF( FT_Error )
    915   tt_face_load_cmap( TT_Face    face,
    916                      FT_Stream  stream )
    917   {
    918     FT_Error  error;
    919 
    920 
    921     error = face->goto_table( face, TTAG_cmap, stream, &face->cmap_size );
    922     if ( error )
    923       goto Exit;
    924 
    925     if ( FT_FRAME_EXTRACT( face->cmap_size, face->cmap_table ) )
    926       face->cmap_size = 0;
    927 
    928   Exit:
    929     return error;
    930   }
    931 
    932 
    933 
    934   /*************************************************************************/
    935   /*                                                                       */
    936   /* <Function>                                                            */
    937   /*    tt_face_load_os2                                                   */
    938   /*                                                                       */
    939   /* <Description>                                                         */
    940   /*    Loads the OS2 table.                                               */
    941   /*                                                                       */
    942   /* <Input>                                                               */
    943   /*    face   :: A handle to the target face object.                      */
    944   /*                                                                       */
    945   /*    stream :: A handle to the input stream.                            */
    946   /*                                                                       */
    947   /* <Return>                                                              */
    948   /*    FreeType error code.  0 means success.                             */
    949   /*                                                                       */
    950   FT_LOCAL_DEF( FT_Error )
    951   tt_face_load_os2( TT_Face    face,
    952                     FT_Stream  stream )
    953   {
    954     FT_Error  error;
    955     TT_OS2*   os2;
    956 
    957     static const FT_Frame_Field  os2_fields[] =
    958     {
    959 #undef  FT_STRUCTURE
    960 #define FT_STRUCTURE  TT_OS2
    961 
    962       FT_FRAME_START( 78 ),
    963         FT_FRAME_USHORT( version ),
    964         FT_FRAME_SHORT ( xAvgCharWidth ),
    965         FT_FRAME_USHORT( usWeightClass ),
    966         FT_FRAME_USHORT( usWidthClass ),
    967         FT_FRAME_SHORT ( fsType ),
    968         FT_FRAME_SHORT ( ySubscriptXSize ),
    969         FT_FRAME_SHORT ( ySubscriptYSize ),
    970         FT_FRAME_SHORT ( ySubscriptXOffset ),
    971         FT_FRAME_SHORT ( ySubscriptYOffset ),
    972         FT_FRAME_SHORT ( ySuperscriptXSize ),
    973         FT_FRAME_SHORT ( ySuperscriptYSize ),
    974         FT_FRAME_SHORT ( ySuperscriptXOffset ),
    975         FT_FRAME_SHORT ( ySuperscriptYOffset ),
    976         FT_FRAME_SHORT ( yStrikeoutSize ),
    977         FT_FRAME_SHORT ( yStrikeoutPosition ),
    978         FT_FRAME_SHORT ( sFamilyClass ),
    979         FT_FRAME_BYTE  ( panose[0] ),
    980         FT_FRAME_BYTE  ( panose[1] ),
    981         FT_FRAME_BYTE  ( panose[2] ),
    982         FT_FRAME_BYTE  ( panose[3] ),
    983         FT_FRAME_BYTE  ( panose[4] ),
    984         FT_FRAME_BYTE  ( panose[5] ),
    985         FT_FRAME_BYTE  ( panose[6] ),
    986         FT_FRAME_BYTE  ( panose[7] ),
    987         FT_FRAME_BYTE  ( panose[8] ),
    988         FT_FRAME_BYTE  ( panose[9] ),
    989         FT_FRAME_ULONG ( ulUnicodeRange1 ),
    990         FT_FRAME_ULONG ( ulUnicodeRange2 ),
    991         FT_FRAME_ULONG ( ulUnicodeRange3 ),
    992         FT_FRAME_ULONG ( ulUnicodeRange4 ),
    993         FT_FRAME_BYTE  ( achVendID[0] ),
    994         FT_FRAME_BYTE  ( achVendID[1] ),
    995         FT_FRAME_BYTE  ( achVendID[2] ),
    996         FT_FRAME_BYTE  ( achVendID[3] ),
    997 
    998         FT_FRAME_USHORT( fsSelection ),
    999         FT_FRAME_USHORT( usFirstCharIndex ),
   1000         FT_FRAME_USHORT( usLastCharIndex ),
   1001         FT_FRAME_SHORT ( sTypoAscender ),
   1002         FT_FRAME_SHORT ( sTypoDescender ),
   1003         FT_FRAME_SHORT ( sTypoLineGap ),
   1004         FT_FRAME_USHORT( usWinAscent ),
   1005         FT_FRAME_USHORT( usWinDescent ),
   1006       FT_FRAME_END
   1007     };
   1008 
   1009     static const FT_Frame_Field  os2_fields_extra[] =
   1010     {
   1011       FT_FRAME_START( 8 ),
   1012         FT_FRAME_ULONG( ulCodePageRange1 ),
   1013         FT_FRAME_ULONG( ulCodePageRange2 ),
   1014       FT_FRAME_END
   1015     };
   1016 
   1017     static const FT_Frame_Field  os2_fields_extra2[] =
   1018     {
   1019       FT_FRAME_START( 10 ),
   1020         FT_FRAME_SHORT ( sxHeight ),
   1021         FT_FRAME_SHORT ( sCapHeight ),
   1022         FT_FRAME_USHORT( usDefaultChar ),
   1023         FT_FRAME_USHORT( usBreakChar ),
   1024         FT_FRAME_USHORT( usMaxContext ),
   1025       FT_FRAME_END
   1026     };
   1027 
   1028 
   1029     /* We now support old Mac fonts where the OS/2 table doesn't  */
   1030     /* exist.  Simply put, we set the `version' field to 0xFFFF   */
   1031     /* and test this value each time we need to access the table. */
   1032     error = face->goto_table( face, TTAG_OS2, stream, 0 );
   1033     if ( error )
   1034       goto Exit;
   1035 
   1036     os2 = &face->os2;
   1037 
   1038     if ( FT_STREAM_READ_FIELDS( os2_fields, os2 ) )
   1039       goto Exit;
   1040 
   1041     os2->ulCodePageRange1 = 0;
   1042     os2->ulCodePageRange2 = 0;
   1043     os2->sxHeight         = 0;
   1044     os2->sCapHeight       = 0;
   1045     os2->usDefaultChar    = 0;
   1046     os2->usBreakChar      = 0;
   1047     os2->usMaxContext     = 0;
   1048 
   1049     if ( os2->version >= 0x0001 )
   1050     {
   1051       /* only version 1 tables */
   1052       if ( FT_STREAM_READ_FIELDS( os2_fields_extra, os2 ) )
   1053         goto Exit;
   1054 
   1055       if ( os2->version >= 0x0002 )
   1056       {
   1057         /* only version 2 tables */
   1058         if ( FT_STREAM_READ_FIELDS( os2_fields_extra2, os2 ) )
   1059           goto Exit;
   1060       }
   1061     }
   1062 
   1063     FT_TRACE3(( "sTypoAscender:  %4d\n",   os2->sTypoAscender ));
   1064     FT_TRACE3(( "sTypoDescender: %4d\n",   os2->sTypoDescender ));
   1065     FT_TRACE3(( "usWinAscent:    %4u\n",   os2->usWinAscent ));
   1066     FT_TRACE3(( "usWinDescent:   %4u\n",   os2->usWinDescent ));
   1067     FT_TRACE3(( "fsSelection:    0x%2x\n", os2->fsSelection ));
   1068 
   1069   Exit:
   1070     return error;
   1071   }
   1072 
   1073 
   1074   /*************************************************************************/
   1075   /*                                                                       */
   1076   /* <Function>                                                            */
   1077   /*    tt_face_load_postscript                                            */
   1078   /*                                                                       */
   1079   /* <Description>                                                         */
   1080   /*    Loads the Postscript table.                                        */
   1081   /*                                                                       */
   1082   /* <Input>                                                               */
   1083   /*    face   :: A handle to the target face object.                      */
   1084   /*                                                                       */
   1085   /*    stream :: A handle to the input stream.                            */
   1086   /*                                                                       */
   1087   /* <Return>                                                              */
   1088   /*    FreeType error code.  0 means success.                             */
   1089   /*                                                                       */
   1090   FT_LOCAL_DEF( FT_Error )
   1091   tt_face_load_post( TT_Face    face,
   1092                      FT_Stream  stream )
   1093   {
   1094     FT_Error        error;
   1095     TT_Postscript*  post = &face->postscript;
   1096 
   1097     static const FT_Frame_Field  post_fields[] =
   1098     {
   1099 #undef  FT_STRUCTURE
   1100 #define FT_STRUCTURE  TT_Postscript
   1101 
   1102       FT_FRAME_START( 32 ),
   1103         FT_FRAME_ULONG( FormatType ),
   1104         FT_FRAME_ULONG( italicAngle ),
   1105         FT_FRAME_SHORT( underlinePosition ),
   1106         FT_FRAME_SHORT( underlineThickness ),
   1107         FT_FRAME_ULONG( isFixedPitch ),
   1108         FT_FRAME_ULONG( minMemType42 ),
   1109         FT_FRAME_ULONG( maxMemType42 ),
   1110         FT_FRAME_ULONG( minMemType1 ),
   1111         FT_FRAME_ULONG( maxMemType1 ),
   1112       FT_FRAME_END
   1113     };
   1114 
   1115 
   1116     error = face->goto_table( face, TTAG_post, stream, 0 );
   1117     if ( error )
   1118       return error;
   1119 
   1120     if ( FT_STREAM_READ_FIELDS( post_fields, post ) )
   1121       return error;
   1122 
   1123     /* we don't load the glyph names, we do that in another */
   1124     /* module (ttpost).                                     */
   1125 
   1126     FT_TRACE3(( "FormatType:   0x%x\n", post->FormatType ));
   1127     FT_TRACE3(( "isFixedPitch:   %s\n", post->isFixedPitch
   1128                                         ? "  yes" : "   no" ));
   1129 
   1130     return FT_Err_Ok;
   1131   }
   1132 
   1133 
   1134   /*************************************************************************/
   1135   /*                                                                       */
   1136   /* <Function>                                                            */
   1137   /*    tt_face_load_pclt                                                  */
   1138   /*                                                                       */
   1139   /* <Description>                                                         */
   1140   /*    Loads the PCL 5 Table.                                             */
   1141   /*                                                                       */
   1142   /* <Input>                                                               */
   1143   /*    face   :: A handle to the target face object.                      */
   1144   /*                                                                       */
   1145   /*    stream :: A handle to the input stream.                            */
   1146   /*                                                                       */
   1147   /* <Return>                                                              */
   1148   /*    FreeType error code.  0 means success.                             */
   1149   /*                                                                       */
   1150   FT_LOCAL_DEF( FT_Error )
   1151   tt_face_load_pclt( TT_Face    face,
   1152                      FT_Stream  stream )
   1153   {
   1154     static const FT_Frame_Field  pclt_fields[] =
   1155     {
   1156 #undef  FT_STRUCTURE
   1157 #define FT_STRUCTURE  TT_PCLT
   1158 
   1159       FT_FRAME_START( 54 ),
   1160         FT_FRAME_ULONG ( Version ),
   1161         FT_FRAME_ULONG ( FontNumber ),
   1162         FT_FRAME_USHORT( Pitch ),
   1163         FT_FRAME_USHORT( xHeight ),
   1164         FT_FRAME_USHORT( Style ),
   1165         FT_FRAME_USHORT( TypeFamily ),
   1166         FT_FRAME_USHORT( CapHeight ),
   1167         FT_FRAME_BYTES ( TypeFace, 16 ),
   1168         FT_FRAME_BYTES ( CharacterComplement, 8 ),
   1169         FT_FRAME_BYTES ( FileName, 6 ),
   1170         FT_FRAME_CHAR  ( StrokeWeight ),
   1171         FT_FRAME_CHAR  ( WidthType ),
   1172         FT_FRAME_BYTE  ( SerifStyle ),
   1173         FT_FRAME_BYTE  ( Reserved ),
   1174       FT_FRAME_END
   1175     };
   1176 
   1177     FT_Error  error;
   1178     TT_PCLT*  pclt = &face->pclt;
   1179 
   1180 
   1181     /* optional table */
   1182     error = face->goto_table( face, TTAG_PCLT, stream, 0 );
   1183     if ( error )
   1184       goto Exit;
   1185 
   1186     if ( FT_STREAM_READ_FIELDS( pclt_fields, pclt ) )
   1187       goto Exit;
   1188 
   1189   Exit:
   1190     return error;
   1191   }
   1192 
   1193 
   1194   /*************************************************************************/
   1195   /*                                                                       */
   1196   /* <Function>                                                            */
   1197   /*    tt_face_load_gasp                                                  */
   1198   /*                                                                       */
   1199   /* <Description>                                                         */
   1200   /*    Loads the `gasp' table into a face object.                         */
   1201   /*                                                                       */
   1202   /* <Input>                                                               */
   1203   /*    face   :: A handle to the target face object.                      */
   1204   /*                                                                       */
   1205   /*    stream :: The input stream.                                        */
   1206   /*                                                                       */
   1207   /* <Return>                                                              */
   1208   /*    FreeType error code.  0 means success.                             */
   1209   /*                                                                       */
   1210   FT_LOCAL_DEF( FT_Error )
   1211   tt_face_load_gasp( TT_Face    face,
   1212                      FT_Stream  stream )
   1213   {
   1214     FT_Error   error;
   1215     FT_Memory  memory = stream->memory;
   1216 
   1217     FT_UInt        j,num_ranges;
   1218     TT_GaspRange   gaspranges = NULL;
   1219 
   1220 
   1221     /* the gasp table is optional */
   1222     error = face->goto_table( face, TTAG_gasp, stream, 0 );
   1223     if ( error )
   1224       goto Exit;
   1225 
   1226     if ( FT_FRAME_ENTER( 4L ) )
   1227       goto Exit;
   1228 
   1229     face->gasp.version   = FT_GET_USHORT();
   1230     face->gasp.numRanges = FT_GET_USHORT();
   1231 
   1232     FT_FRAME_EXIT();
   1233 
   1234     /* only support versions 0 and 1 of the table */
   1235     if ( face->gasp.version >= 2 )
   1236     {
   1237       face->gasp.numRanges = 0;
   1238       error = FT_THROW( Invalid_Table );
   1239       goto Exit;
   1240     }
   1241 
   1242     num_ranges = face->gasp.numRanges;
   1243     FT_TRACE3(( "numRanges: %u\n", num_ranges ));
   1244 
   1245     if ( FT_QNEW_ARRAY( face->gasp.gaspRanges, num_ranges ) ||
   1246          FT_FRAME_ENTER( num_ranges * 4L )                  )
   1247       goto Exit;
   1248 
   1249     gaspranges = face->gasp.gaspRanges;
   1250 
   1251     for ( j = 0; j < num_ranges; j++ )
   1252     {
   1253       gaspranges[j].maxPPEM  = FT_GET_USHORT();
   1254       gaspranges[j].gaspFlag = FT_GET_USHORT();
   1255 
   1256       FT_TRACE3(( "gaspRange %d: rangeMaxPPEM %5d, rangeGaspBehavior 0x%x\n",
   1257                   j,
   1258                   gaspranges[j].maxPPEM,
   1259                   gaspranges[j].gaspFlag ));
   1260     }
   1261 
   1262     FT_FRAME_EXIT();
   1263 
   1264   Exit:
   1265     return error;
   1266   }
   1267 
   1268 
   1269 /* END */
   1270