ftobjs.c.svn-base

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  /*    find_unicode_charmap                                               */
  /*                                                                       */
  /* <Description>                                                         */
  /*    This function finds a Unicode charmap, if there is one.            */
  /*    And if there is more than one, it tries to favour the more         */
  /*    extensive one, i.e., one that supports UCS-4 against those which   */
  /*    are limited to the BMP (said UCS-2 encoding.)                      */
  /*                                                                       */
  /*    This function is called from open_face() (just below), and also    */
  /*    from FT_Select_Charmap( ..., FT_ENCODING_UNICODE ).                */
  /*                                                                       */
  static FT_Error
  find_unicode_charmap( FT_Face  face )
  {
    FT_CharMap*  first;
    FT_CharMap*  cur;


    /* caller should have already checked that `face' is valid */
    FT_ASSERT( face );

    first = face->charmaps;

    if ( !first )
      return FT_Err_Invalid_CharMap_Handle;

    /*
     *  The original TrueType specification(s) only specified charmap
     *  formats that are capable of mapping 8 or 16 bit character codes to
     *  glyph indices.
     *
     *  However, recent updates to the Apple and OpenType specifications
     *  introduced new formats that are capable of mapping 32-bit character
     *  codes as well.  And these are already used on some fonts, mainly to
     *  map non-BMP Asian ideographs as defined in Unicode.
     *
     *  For compatibility purposes, these fonts generally come with
     *  *several* Unicode charmaps:
     *
     *   - One of them in the "old" 16-bit format, that cannot access
     *     all glyphs in the font.
     *
     *   - Another one in the "new" 32-bit format, that can access all
     *     the glyphs.
     *
     *  This function has been written to always favor a 32-bit charmap
     *  when found.  Otherwise, a 16-bit one is returned when found.
     */

    /* Since the `interesting' table, with IDs (3,10), is normally the */
    /* last one, we loop backwards.  This loses with type1 fonts with  */
    /* non-BMP characters (<.0001%), this wins with .ttf with non-BMP  */
    /* chars (.01% ?), and this is the same about 99.99% of the time!  */

    cur = first + face->num_charmaps;  /* points after the last one */

    for ( ; --cur >= first; )
    {
      if ( cur[0]->encoding == FT_ENCODING_UNICODE )
      {
        /* XXX If some new encodings to represent UCS-4 are added, */
        /*     they should be added here.                          */
        if ( ( cur[0]->platform_id == TT_PLATFORM_MICROSOFT &&
               cur[0]->encoding_id == TT_MS_ID_UCS_4        )     ||
             ( cur[0]->platform_id == TT_PLATFORM_APPLE_UNICODE &&
               cur[0]->encoding_id == TT_APPLE_ID_UNICODE_32    ) )
        {
          face->charmap = cur[0];
          return FT_Err_Ok;
        }
      }
    }

    /* We do not have any UCS-4 charmap.                */
    /* Do the loop again and search for UCS-2 charmaps. */
    cur = first + face->num_charmaps;

    for ( ; --cur >= first; )
    {
      if ( cur[0]->encoding == FT_ENCODING_UNICODE )
      {
        face->charmap = cur[0];
        return FT_Err_Ok;
      }
    }

    return FT_Err_Invalid_CharMap_Handle;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    find_variant_selector_charmap                                      */
  /*                                                                       */
  /* <Description>                                                         */
  /*    This function finds the variant selector charmap, if there is one. */
  /*    There can only be one (platform=0, specific=5, format=14).         */
  /*                                                                       */
  static FT_CharMap
  find_variant_selector_charmap( FT_Face  face )
  {
    FT_CharMap*  first;
    FT_CharMap*  end;
    FT_CharMap*  cur;


    /* caller should have already checked that `face' is valid */
    FT_ASSERT( face );

    first = face->charmaps;

    if ( !first )
      return NULL;

    end = first + face->num_charmaps;  /* points after the last one */

    for ( cur = first; cur < end; ++cur )
    {
      if ( cur[0]->platform_id == TT_PLATFORM_APPLE_UNICODE    &&
           cur[0]->encoding_id == TT_APPLE_ID_VARIANT_SELECTOR &&
           FT_Get_CMap_Format( cur[0] ) == 14                  )
        return cur[0];
    }

    return NULL;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    open_face                                                          */
  /*                                                                       */
  /* <Description>                                                         */
  /*    This function does some work for FT_Open_Face().                   */
  /*                                                                       */
  static FT_Error
  open_face( FT_Driver      driver,
             FT_Stream      stream,
             FT_Long        face_index,
             FT_Int         num_params,
             FT_Parameter*  params,
             FT_Face       *aface )
  {
    FT_Memory         memory;
    FT_Driver_Class   clazz;
    FT_Face           face = 0;
    FT_Error          error, error2;
    FT_Face_Internal  internal = NULL;


    clazz  = driver->clazz;
    memory = driver->root.memory;

    /* allocate the face object and perform basic initialization */
    if ( FT_ALLOC( face, clazz->face_object_size ) )
      goto Fail;

    if ( FT_NEW( internal ) )
      goto Fail;

    face->internal = internal;

    face->driver   = driver;
    face->memory   = memory;
    face->stream   = stream;

#ifdef FT_CONFIG_OPTION_INCREMENTAL
    {
      int  i;


      face->internal->incremental_interface = 0;
      for ( i = 0; i < num_params && !face->internal->incremental_interface;
            i++ )
        if ( params[i].tag == FT_PARAM_TAG_INCREMENTAL )
          face->internal->incremental_interface =
            (FT_Incremental_Interface)params[i].data;
    }
#endif

    if ( clazz->init_face )
      error = clazz->init_face( stream,
                                face,
                                (FT_Int)face_index,
                                num_params,
                                params );
    if ( error )
      goto Fail;

    /* select Unicode charmap by default */
    error2 = find_unicode_charmap( face );

    /* if no Unicode charmap can be found, FT_Err_Invalid_CharMap_Handle */
    /* is returned.                                                      */

    /* no error should happen, but we want to play safe */
    if ( error2 && error2 != FT_Err_Invalid_CharMap_Handle )
    {
      error = error2;
      goto Fail;
    }

    *aface = face;

  Fail:
    if ( error )
    {
      destroy_charmaps( face, memory );
      if ( clazz->done_face )
        clazz->done_face( face );
      FT_FREE( internal );
      FT_FREE( face );
      *aface = 0;
    }

    return error;
  }


  /* there's a Mac-specific extended implementation of FT_New_Face() */
  /* in src/base/ftmac.c                                             */

#ifndef FT_MACINTOSH

  /* documentation is in freetype.h */

  FT_EXPORT_DEF( FT_Error )
  FT_New_Face( FT_Library   library,
               const char*  pathname,
               FT_Long      face_index,
               FT_Face     *aface )
  {
    FT_Open_Args  args;


    /* test for valid `library' and `aface' delayed to FT_Open_Face() */
    if ( !pathname )
      return FT_Err_Invalid_Argument;

    args.flags    = FT_OPEN_PATHNAME;
    args.pathname = (char*)pathname;

    return FT_Open_Face( library, &args, face_index, aface );
  }

#endif  /* !FT_MACINTOSH */


  /* documentation is in freetype.h */

  FT_EXPORT_DEF( FT_Error )
  FT_New_Memory_Face( FT_Library      library,
                      const FT_Byte*  file_base,
                      FT_Long         file_size,
                      FT_Long         face_index,
                      FT_Face        *aface )
  {
    FT_Open_Args  args;


    /* test for valid `library' and `face' delayed to FT_Open_Face() */
    if ( !file_base )
      return FT_Err_Invalid_Argument;

    args.flags       = FT_OPEN_MEMORY;
    args.memory_base = file_base;
    args.memory_size = file_size;

    return FT_Open_Face( library, &args, face_index, aface );
  }


#if !defined( FT_MACINTOSH ) && defined( FT_CONFIG_OPTION_MAC_FONTS )

  /* The behavior here is very similar to that in base/ftmac.c, but it     */
  /* is designed to work on non-mac systems, so no mac specific calls.     */
  /*                                                                       */
  /* We look at the file and determine if it is a mac dfont file or a mac  */
  /* resource file, or a macbinary file containing a mac resource file.    */
  /*                                                                       */
  /* Unlike ftmac I'm not going to look at a `FOND'.  I don't really see   */
  /* the point, especially since there may be multiple `FOND' resources.   */
  /* Instead I'll just look for `sfnt' and `POST' resources, ordered as    */
  /* they occur in the file.                                               */
  /*                                                                       */
  /* Note that multiple `POST' resources do not mean multiple postscript   */
  /* fonts; they all get jammed together to make what is essentially a     */
  /* pfb file.                                                             */
  /*                                                                       */
  /* We aren't interested in `NFNT' or `FONT' bitmap resources.            */
  /*                                                                       */
  /* As soon as we get an `sfnt' load it into memory and pass it off to    */
  /* FT_Open_Face.                                                         */
  /*                                                                       */
  /* If we have a (set of) `POST' resources, massage them into a (memory)  */
  /* pfb file and pass that to FT_Open_Face.  (As with ftmac.c I'm not     */
  /* going to try to save the kerning info.  After all that lives in the   */
  /* `FOND' which isn't in the file containing the `POST' resources so     */
  /* we don't really have access to it.                                    */


  /* Finalizer for a memory stream; gets called by FT_Done_Face().
     It frees the memory it uses. */
  /* from ftmac.c */
  static void
  memory_stream_close( FT_Stream  stream )
  {
    FT_Memory  memory = stream->memory;


    FT_FREE( stream->base );

    stream->size  = 0;
    stream->base  = 0;
    stream->close = 0;
  }


  /* Create a new memory stream from a buffer and a size. */
  /* from ftmac.c */
  static FT_Error
  new_memory_stream( FT_Library           library,
                     FT_Byte*             base,
                     FT_ULong             size,
                     FT_Stream_CloseFunc  close,
                     FT_Stream           *astream )
  {
    FT_Error   error;
    FT_Memory  memory;
    FT_Stream  stream;


    if ( !library )
      return FT_Err_Invalid_Library_Handle;

    if ( !base )
      return FT_Err_Invalid_Argument;

    *astream = 0;
    memory = library->memory;
    if ( FT_NEW( stream ) )
      goto Exit;

    FT_Stream_OpenMemory( stream, base, size );

    stream->close = close;

    *astream = stream;

  Exit:
    return error;
  }


  /* Create a new FT_Face given a buffer and a driver name. */
  /* from ftmac.c */
  static FT_Error
  open_face_from_buffer( FT_Library   library,
                         FT_Byte*     base,
                         FT_ULong     size,
                         FT_Long      face_index,
                         const char*  driver_name,
                         FT_Face     *aface )
  {
    FT_Open_Args  args;
    FT_Error      error;
    FT_Stream     stream = NULL;
    FT_Memory     memory = library->memory;


    error = new_memory_stream( library,
                               base,
                               size,
                               memory_stream_close,
                               &stream );
    if ( error )
    {
      FT_FREE( base );
      return error;
    }

    args.flags = FT_OPEN_STREAM;
    args.stream = stream;
    if ( driver_name )
    {
      args.flags = args.flags | FT_OPEN_DRIVER;
      args.driver = FT_Get_Module( library, driver_name );
    }

    error = FT_Open_Face( library, &args, face_index, aface );

    if ( error == FT_Err_Ok )
      (*aface)->face_flags &= ~FT_FACE_FLAG_EXTERNAL_STREAM;
    else
    {
      FT_Stream_Close( stream );
      FT_FREE( stream );
    }

    return error;
  }


  /* The resource header says we've got resource_cnt `POST' (type1) */
  /* resources in this file.  They all need to be coalesced into    */
  /* one lump which gets passed on to the type1 driver.             */
  /* Here can be only one PostScript font in a file so face_index   */
  /* must be 0 (or -1).                                             */
  /*                                                                */
  static FT_Error
  Mac_Read_POST_Resource( FT_Library  library,
                          FT_Stream   stream,
                          FT_Long    *offsets,
                          FT_Long     resource_cnt,
                          FT_Long     face_index,
                          FT_Face    *aface )
  {
    FT_Error   error  = FT_Err_Cannot_Open_Resource;
    FT_Memory  memory = library->memory;
    FT_Byte*   pfb_data;
    int        i, type, flags;
    FT_Long    len;
    FT_Long    pfb_len, pfb_pos, pfb_lenpos;
    FT_Long    rlen, temp;


    if ( face_index == -1 )
      face_index = 0;
    if ( face_index != 0 )
      return error;

    /* Find the length of all the POST resources, concatenated.  Assume */
    /* worst case (each resource in its own section).                   */
    pfb_len = 0;
    for ( i = 0; i < resource_cnt; ++i )
    {
      error = FT_Stream_Seek( stream, offsets[i] );
      if ( error )
        goto Exit;
      if ( FT_READ_LONG( temp ) )
        goto Exit;
      pfb_len += temp + 6;