📄 ttload.c
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FT_TRACE3(( "tt_face_load_sfnt_header: file is a collection\n" ));
/* It is a TrueType collection, i.e. a file containing several */
/* font files. Read the font directory now */
if ( FT_STREAM_READ_FIELDS( ttc_header_fields, &face->ttc_header ) )
goto Exit;
/* now read the offsets of each font in the file */
if ( FT_NEW_ARRAY( face->ttc_header.offsets, face->ttc_header.count ) ||
FT_FRAME_ENTER( face->ttc_header.count * 4L ) )
goto Exit;
for ( n = 0; n < face->ttc_header.count; n++ )
face->ttc_header.offsets[n] = FT_GET_ULONG();
FT_FRAME_EXIT();
/* check face index */
if ( face_index >= face->ttc_header.count )
{
error = SFNT_Err_Bad_Argument;
goto Exit;
}
/* seek to the appropriate TrueType file, then read tag */
offset = face->ttc_header.offsets[face_index];
if ( FT_STREAM_SEEK( offset ) ||
FT_READ_LONG( format_tag ) )
goto Exit;
}
/* the format tag was read, now check the rest of the header */
sfnt->format_tag = format_tag;
sfnt->offset = offset;
if ( FT_STREAM_READ_FIELDS( sfnt_header_fields, sfnt ) )
goto Exit;
/* now check the sfnt directory */
error = sfnt_dir_check( stream, offset, sfnt->num_tables );
if ( error )
{
FT_TRACE2(( "tt_face_load_sfnt_header: file is not SFNT!\n" ));
error = SFNT_Err_Unknown_File_Format;
goto Exit;
}
/* disallow face index values > 0 for non-TTC files */
if ( font_format_tag != TTAG_ttcf && face_index > 0 )
error = SFNT_Err_Bad_Argument;
Exit:
return error;
}
/*************************************************************************/
/* */
/* <Function> */
/* tt_face_load_directory */
/* */
/* <Description> */
/* Loads the table directory into a face object. */
/* */
/* <InOut> */
/* face :: A handle to the target face object. */
/* */
/* <Input> */
/* stream :: The input stream. */
/* */
/* sfnt :: The SFNT directory header. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
/* <Note> */
/* The stream cursor must be at the font file's origin. */
/* */
FT_LOCAL_DEF( FT_Error )
tt_face_load_directory( TT_Face face,
FT_Stream stream,
SFNT_Header sfnt )
{
FT_Error error;
FT_Memory memory = stream->memory;
TT_TableRec *entry, *limit;
FT_TRACE2(( "tt_face_load_directory: %08p\n", face ));
FT_TRACE2(( "-- Tables count: %12u\n", sfnt->num_tables ));
FT_TRACE2(( "-- Format version: %08lx\n", sfnt->format_tag ));
face->num_tables = sfnt->num_tables;
if ( FT_QNEW_ARRAY( face->dir_tables, face->num_tables ) )
goto Exit;
if ( FT_STREAM_SEEK( sfnt->offset + 12 ) ||
FT_FRAME_ENTER( face->num_tables * 16L ) )
goto Exit;
entry = face->dir_tables;
limit = entry + face->num_tables;
for ( ; entry < limit; entry++ )
{ /* loop through the tables and get all entries */
entry->Tag = FT_GET_TAG4();
entry->CheckSum = FT_GET_ULONG();
entry->Offset = FT_GET_LONG();
entry->Length = FT_GET_LONG();
FT_TRACE2(( " %c%c%c%c - %08lx - %08lx\n",
(FT_Char)( entry->Tag >> 24 ),
(FT_Char)( entry->Tag >> 16 ),
(FT_Char)( entry->Tag >> 8 ),
(FT_Char)( entry->Tag ),
entry->Offset,
entry->Length ));
}
FT_FRAME_EXIT();
FT_TRACE2(( "Directory loaded\n\n" ));
Exit:
return error;
}
/*************************************************************************/
/* */
/* <Function> */
/* tt_face_load_any */
/* */
/* <Description> */
/* Loads any font table into client memory. */
/* */
/* <Input> */
/* face :: The face object to look for. */
/* */
/* tag :: The tag of table to load. Use the value 0 if you want */
/* to access the whole font file, else set this parameter */
/* to a valid TrueType table tag that you can forge with */
/* the MAKE_TT_TAG macro. */
/* */
/* offset :: The starting offset in the table (or the file if */
/* tag == 0). */
/* */
/* length :: The address of the decision variable: */
/* */
/* If length == NULL: */
/* Loads the whole table. Returns an error if */
/* `offset' == 0! */
/* */
/* If *length == 0: */
/* Exits immediately; returning the length of the given */
/* table or of the font file, depending on the value of */
/* `tag'. */
/* */
/* If *length != 0: */
/* Loads the next `length' bytes of table or font, */
/* starting at offset `offset' (in table or font too). */
/* */
/* <Output> */
/* buffer :: The address of target buffer. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
FT_LOCAL_DEF( FT_Error )
tt_face_load_any( TT_Face face,
FT_ULong tag,
FT_Long offset,
FT_Byte* buffer,
FT_ULong* length )
{
FT_Error error;
FT_Stream stream;
TT_Table table;
FT_ULong size;
if ( tag != 0 )
{
/* look for tag in font directory */
table = tt_face_lookup_table( face, tag );
if ( !table )
{
error = SFNT_Err_Table_Missing;
goto Exit;
}
offset += table->Offset;
size = table->Length;
}
else
/* tag == 0 -- the user wants to access the font file directly */
size = face->root.stream->size;
if ( length && *length == 0 )
{
*length = size;
return SFNT_Err_Ok;
}
if ( length )
size = *length;
stream = face->root.stream;
/* the `if' is syntactic sugar for picky compilers */
if ( FT_STREAM_READ_AT( offset, buffer, size ) )
goto Exit;
Exit:
return error;
}
/*************************************************************************/
/* */
/* <Function> */
/* tt_face_load_generic_header */
/* */
/* <Description> */
/* Loads the TrueType table `head' or `bhed'. */
/* */
/* <Input> */
/* face :: A handle to the target face object. */
/* */
/* stream :: The input stream. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
static FT_Error
tt_face_load_generic_header( TT_Face face,
FT_Stream stream,
FT_ULong tag )
{
FT_Error error;
TT_Header* header;
static const FT_Frame_Field header_fields[] =
{
#undef FT_STRUCTURE
#define FT_STRUCTURE TT_Header
FT_FRAME_START( 54 ),
FT_FRAME_ULONG ( Table_Version ),
FT_FRAME_ULONG ( Font_Revision ),
FT_FRAME_LONG ( CheckSum_Adjust ),
FT_FRAME_LONG ( Magic_Number ),
FT_FRAME_USHORT( Flags ),
FT_FRAME_USHORT( Units_Per_EM ),
FT_FRAME_LONG ( Created[0] ),
FT_FRAME_LONG ( Created[1] ),
FT_FRAME_LONG ( Modified[0] ),
FT_FRAME_LONG ( Modified[1] ),
FT_FRAME_SHORT ( xMin ),
FT_FRAME_SHORT ( yMin ),
FT_FRAME_SHORT ( xMax ),
FT_FRAME_SHORT ( yMax ),
FT_FRAME_USHORT( Mac_Style ),
FT_FRAME_USHORT( Lowest_Rec_PPEM ),
FT_FRAME_SHORT ( Font_Direction ),
FT_FRAME_SHORT ( Index_To_Loc_Format ),
FT_FRAME_SHORT ( Glyph_Data_Format ),
FT_FRAME_END
};
FT_TRACE2(( "tt_face_load_generic_header: "
"%08p, looking up font table `%c%c%c%c'.\n",
face,
(FT_Char)( tag >> 24 ),
(FT_Char)( tag >> 16 ),
(FT_Char)( tag >> 8 ),
(FT_Char)( tag ) ));
error = face->goto_table( face, tag, stream, 0 );
if ( error )
{
FT_TRACE2(( "tt_face_load_generic_header: Font table is missing!\n" ));
goto Exit;
}
header = &face->header;
if ( FT_STREAM_READ_FIELDS( header_fields, header ) )
goto Exit;
FT_TRACE2(( " Units per EM: %8u\n", header->Units_Per_EM ));
FT_TRACE2(( " IndexToLoc: %8d\n", header->Index_To_Loc_Format ));
FT_TRACE2(( "tt_face_load_generic_header: Font table loaded.\n" ));
Exit:
return error;
}
FT_LOCAL_DEF( FT_Error )
tt_face_load_header( TT_Face face,
FT_Stream stream )
{
return tt_face_load_generic_header( face, stream, TTAG_head );
}
#ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
FT_LOCAL_DEF( FT_Error )
tt_face_load_bitmap_header( TT_Face face,
FT_Stream stream )
{
return tt_face_load_generic_header( face, stream, TTAG_bhed );
}
#endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */
/*************************************************************************/
/* */
/* <Function> */
/* tt_face_load_max_profile */
/* */
/* <Description> */
/* Loads the maximum profile into a face object. */
/* */
/* <Input> */
/* face :: A handle to the target face object. */
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