harfbuzz/src/harfbuzz-gpos.c

/*******************************************************************
 *
 *  Copyright 1996-2000 by
 *  David Turner, Robert Wilhelm, and Werner Lemberg.
 *
 *  Copyright 2006  Behdad Esfahbod
 *  Copyright 2007  Red Hat Software
 *
 *  This is part of HarfBuzz, an OpenType Layout engine library.
 *
 *  See the file name COPYING for licensing information.
 *
 ******************************************************************/
#include "harfbuzz-impl.h"
#include "harfbuzz-gpos-private.h"
#include "harfbuzz-open-private.h"
#include "harfbuzz-gdef-private.h"

struct  GPOS_Instance_
{
  HB_GPOSHeader*  gpos;
  FT_Face          face;
  FT_Bool          dvi;
  FT_UShort        load_flags;  /* how the glyph should be loaded */
  FT_Bool          r2l;

  FT_UShort        last;        /* the last valid glyph -- used
				   with cursive positioning     */
  FT_Pos           anchor_x;    /* the coordinates of the anchor point */
  FT_Pos           anchor_y;    /* of the last valid glyph             */
};

typedef struct GPOS_Instance_  GPOS_Instance;


static HB_Error  GPOS_Do_Glyph_Lookup( GPOS_Instance*    gpi,
				       FT_UShort         lookup_index,
				       HB_Buffer        buffer,
				       FT_UShort         context_length,
				       int               nesting_level );



/* the client application must replace this with something more
   meaningful if multiple master fonts are to be supported.     */

static HB_Error  default_mmfunc( FT_Face      face,
				 FT_UShort    metric_id,
				 FT_Pos*      metric_value,
				 void*        data )
{
  FT_UNUSED(face);
  FT_UNUSED(metric_id);
  FT_UNUSED(metric_value);
  FT_UNUSED(data);
  return _hb_err(HB_Err_No_MM_Interpreter);
}



HB_Error  HB_Load_GPOS_Table( FT_Face          face,
			      HB_GPOSHeader** retptr,
			      HB_GDEFHeader*  gdef )
{
  FT_ULong         cur_offset, new_offset, base_offset;

  FT_UShort        i, num_lookups;
  HB_GPOSHeader*  gpos;
  HB_Lookup*      lo;

  FT_Stream  stream = face->stream;
  HB_Error   error;
  FT_Memory  memory = face->memory;


  if ( !retptr )
    return HB_Err_Invalid_Argument;

  if (( error = _hb_ftglue_face_goto_table( face, TTAG_GPOS, stream ) ))
    return error;

  base_offset = FILE_Pos();

  if ( ALLOC ( gpos, sizeof( *gpos ) ) )
    return error;

  gpos->memory = memory;
  gpos->gfunc = FT_Load_Glyph;
  gpos->mmfunc = default_mmfunc;

  /* skip version */

  if ( FILE_Seek( base_offset + 4L ) ||
       ACCESS_Frame( 2L ) )
    goto Fail4;

  new_offset = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_ScriptList( &gpos->ScriptList,
				  stream ) ) != HB_Err_Ok )
    goto Fail4;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 2L ) )
    goto Fail3;

  new_offset = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_FeatureList( &gpos->FeatureList,
				   stream ) ) != HB_Err_Ok )
    goto Fail3;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 2L ) )
    goto Fail2;

  new_offset = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_LookupList( &gpos->LookupList,
				  stream, HB_Type_GPOS ) ) != HB_Err_Ok )
    goto Fail2;

  gpos->gdef = gdef;      /* can be NULL */

  /* We now check the LookupFlags for values larger than 0xFF to find
     out whether we need to load the `MarkAttachClassDef' field of the
     GDEF table -- this hack is necessary for OpenType 1.2 tables since
     the version field of the GDEF table hasn't been incremented.

     For constructed GDEF tables, we only load it if
     `MarkAttachClassDef_offset' is not zero (nevertheless, a build of
     a constructed mark attach table is not supported currently).       */

  if ( gdef &&
       gdef->MarkAttachClassDef_offset && !gdef->MarkAttachClassDef.loaded )
  {
    lo          = gpos->LookupList.Lookup;
    num_lookups = gpos->LookupList.LookupCount;

    for ( i = 0; i < num_lookups; i++ )
    {
      if ( lo[i].LookupFlag & HB_LOOKUP_FLAG_IGNORE_SPECIAL_MARKS )
      {
	if ( FILE_Seek( gdef->MarkAttachClassDef_offset ) ||
	     ( error = _HB_OPEN_Load_ClassDefinition( &gdef->MarkAttachClassDef,
					     256, stream ) ) != HB_Err_Ok )
	  goto Fail1;

	break;
      }
    }
  }

  *retptr = gpos;

  return HB_Err_Ok;

Fail1:
  _HB_OPEN_Free_LookupList( &gpos->LookupList, HB_Type_GPOS, memory );

Fail2:
  _HB_OPEN_Free_FeatureList( &gpos->FeatureList, memory );

Fail3:
  _HB_OPEN_Free_ScriptList( &gpos->ScriptList, memory );

Fail4:
  FREE( gpos );

  return error;
}


HB_Error  HB_Done_GPOS_Table( HB_GPOSHeader* gpos )
{
  FT_Memory memory = gpos->memory;

  _HB_OPEN_Free_LookupList( &gpos->LookupList, HB_Type_GPOS, memory );
  _HB_OPEN_Free_FeatureList( &gpos->FeatureList, memory );
  _HB_OPEN_Free_ScriptList( &gpos->ScriptList, memory );

  FREE( gpos );

  return HB_Err_Ok;
}


/*****************************
 * SubTable related functions
 *****************************/

/* shared tables */

/* ValueRecord */

/* There is a subtle difference in the specs between a `table' and a
   `record' -- offsets for device tables in ValueRecords are taken from
   the parent table and not the parent record.                          */

static HB_Error  Load_ValueRecord( HB_ValueRecord*  vr,
				   FT_UShort         format,
				   FT_ULong          base_offset,
				   FT_Stream         stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_ULong cur_offset, new_offset;


  if ( format & HB_GPOS_FORMAT_HAVE_X_PLACEMENT )
  {
    if ( ACCESS_Frame( 2L ) )
      return error;

    vr->XPlacement = GET_Short();

    FORGET_Frame();
  }
  else
    vr->XPlacement = 0;

  if ( format & HB_GPOS_FORMAT_HAVE_Y_PLACEMENT )
  {
    if ( ACCESS_Frame( 2L ) )
      return error;

    vr->YPlacement = GET_Short();

    FORGET_Frame();
  }
  else
    vr->YPlacement = 0;

  if ( format & HB_GPOS_FORMAT_HAVE_X_ADVANCE )
  {
    if ( ACCESS_Frame( 2L ) )
      return error;

    vr->XAdvance = GET_Short();

    FORGET_Frame();
  }
  else
    vr->XAdvance = 0;

  if ( format & HB_GPOS_FORMAT_HAVE_Y_ADVANCE )
  {
    if ( ACCESS_Frame( 2L ) )
      return error;

    vr->YAdvance = GET_Short();

    FORGET_Frame();
  }
  else
    vr->YAdvance = 0;

  if ( format & HB_GPOS_FORMAT_HAVE_X_PLACEMENT_DEVICE )
  {
    if ( ACCESS_Frame( 2L ) )
      return error;

    new_offset = GET_UShort();

    FORGET_Frame();

    if ( new_offset )
    {
      new_offset += base_offset;

      cur_offset = FILE_Pos();
      if ( FILE_Seek( new_offset ) ||
	   ( error = _HB_OPEN_Load_Device( &vr->XPlacementDevice,
				  stream ) ) != HB_Err_Ok )
	return error;
      (void)FILE_Seek( cur_offset );
    }
    else
      goto empty1;
  }
  else
  {
  empty1:
    vr->XPlacementDevice.StartSize  = 0;
    vr->XPlacementDevice.EndSize    = 0;
    vr->XPlacementDevice.DeltaValue = NULL;
  }

  if ( format & HB_GPOS_FORMAT_HAVE_Y_PLACEMENT_DEVICE )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail3;

    new_offset = GET_UShort();

    FORGET_Frame();

    if ( new_offset )
    {
      new_offset += base_offset;

      cur_offset = FILE_Pos();
      if ( FILE_Seek( new_offset ) ||
	   ( error = _HB_OPEN_Load_Device( &vr->YPlacementDevice,
				  stream ) ) != HB_Err_Ok )
	goto Fail3;
      (void)FILE_Seek( cur_offset );
    }
    else
      goto empty2;
  }
  else
  {
  empty2:
    vr->YPlacementDevice.StartSize  = 0;
    vr->YPlacementDevice.EndSize    = 0;
    vr->YPlacementDevice.DeltaValue = NULL;
  }

  if ( format & HB_GPOS_FORMAT_HAVE_X_ADVANCE_DEVICE )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail2;

    new_offset = GET_UShort();

    FORGET_Frame();

    if ( new_offset )
    {
      new_offset += base_offset;

      cur_offset = FILE_Pos();
      if ( FILE_Seek( new_offset ) ||
	   ( error = _HB_OPEN_Load_Device( &vr->XAdvanceDevice,
				  stream ) ) != HB_Err_Ok )
	goto Fail2;
      (void)FILE_Seek( cur_offset );
    }
    else
      goto empty3;
  }
  else
  {
  empty3:
    vr->XAdvanceDevice.StartSize  = 0;
    vr->XAdvanceDevice.EndSize    = 0;
    vr->XAdvanceDevice.DeltaValue = NULL;
  }

  if ( format & HB_GPOS_FORMAT_HAVE_Y_ADVANCE_DEVICE )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail1;

    new_offset = GET_UShort();

    FORGET_Frame();

    if ( new_offset )
    {
      new_offset += base_offset;

      cur_offset = FILE_Pos();
      if ( FILE_Seek( new_offset ) ||
	   ( error = _HB_OPEN_Load_Device( &vr->YAdvanceDevice,
				  stream ) ) != HB_Err_Ok )
	goto Fail1;
      (void)FILE_Seek( cur_offset );
    }
    else
      goto empty4;
  }
  else
  {
  empty4:
    vr->YAdvanceDevice.StartSize  = 0;
    vr->YAdvanceDevice.EndSize    = 0;
    vr->YAdvanceDevice.DeltaValue = NULL;
  }

  if ( format & HB_GPOS_FORMAT_HAVE_X_ID_PLACEMENT )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail1;

    vr->XIdPlacement = GET_UShort();

    FORGET_Frame();
  }
  else
    vr->XIdPlacement = 0;

  if ( format & HB_GPOS_FORMAT_HAVE_Y_ID_PLACEMENT )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail1;

    vr->YIdPlacement = GET_UShort();

    FORGET_Frame();
  }
  else
    vr->YIdPlacement = 0;

  if ( format & HB_GPOS_FORMAT_HAVE_X_ID_ADVANCE )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail1;

    vr->XIdAdvance = GET_UShort();

    FORGET_Frame();
  }
  else
    vr->XIdAdvance = 0;

  if ( format & HB_GPOS_FORMAT_HAVE_Y_ID_ADVANCE )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail1;

    vr->YIdAdvance = GET_UShort();

    FORGET_Frame();
  }
  else
    vr->YIdAdvance = 0;

  return HB_Err_Ok;

Fail1:
  _HB_OPEN_Free_Device( &vr->YAdvanceDevice, memory );

Fail2:
  _HB_OPEN_Free_Device( &vr->XAdvanceDevice, memory );

Fail3:
  _HB_OPEN_Free_Device( &vr->YPlacementDevice, memory );
  return error;
}


static void  Free_ValueRecord( HB_ValueRecord*  vr,
			       FT_UShort         format,
			       FT_Memory         memory )
{
  if ( format & HB_GPOS_FORMAT_HAVE_Y_ADVANCE_DEVICE )
    _HB_OPEN_Free_Device( &vr->YAdvanceDevice, memory );
  if ( format & HB_GPOS_FORMAT_HAVE_X_ADVANCE_DEVICE )
    _HB_OPEN_Free_Device( &vr->XAdvanceDevice, memory );
  if ( format & HB_GPOS_FORMAT_HAVE_Y_PLACEMENT_DEVICE )
    _HB_OPEN_Free_Device( &vr->YPlacementDevice, memory );
  if ( format & HB_GPOS_FORMAT_HAVE_X_PLACEMENT_DEVICE )
    _HB_OPEN_Free_Device( &vr->XPlacementDevice, memory );
}


static HB_Error  Get_ValueRecord( GPOS_Instance*    gpi,
				  HB_ValueRecord*  vr,
				  FT_UShort         format,
				  HB_Position      gd )
{
  FT_Pos           value;
  FT_Short         pixel_value;
  HB_Error         error = HB_Err_Ok;
  HB_GPOSHeader*  gpos = gpi->gpos;

  FT_UShort  x_ppem, y_ppem;
  FT_Fixed   x_scale, y_scale;


  if ( !format )
    return HB_Err_Ok;

  x_ppem  = gpi->face->size->metrics.x_ppem;
  y_ppem  = gpi->face->size->metrics.y_ppem;
  x_scale = gpi->face->size->metrics.x_scale;
  y_scale = gpi->face->size->metrics.y_scale;

  /* design units -> fractional pixel */

  if ( format & HB_GPOS_FORMAT_HAVE_X_PLACEMENT )
    gd->x_pos += x_scale * vr->XPlacement / 0x10000;
  if ( format & HB_GPOS_FORMAT_HAVE_Y_PLACEMENT )
    gd->y_pos += y_scale * vr->YPlacement / 0x10000;
  if ( format & HB_GPOS_FORMAT_HAVE_X_ADVANCE )
    gd->x_advance += x_scale * vr->XAdvance / 0x10000;
  if ( format & HB_GPOS_FORMAT_HAVE_Y_ADVANCE )
    gd->y_advance += y_scale * vr->YAdvance / 0x10000;

  if ( !gpi->dvi )
  {
    /* pixel -> fractional pixel */

    if ( format & HB_GPOS_FORMAT_HAVE_X_PLACEMENT_DEVICE )
    {
      _HB_OPEN_Get_Device( &vr->XPlacementDevice, x_ppem, &pixel_value );
      gd->x_pos += pixel_value << 6;
    }
    if ( format & HB_GPOS_FORMAT_HAVE_Y_PLACEMENT_DEVICE )
    {
      _HB_OPEN_Get_Device( &vr->YPlacementDevice, y_ppem, &pixel_value );
      gd->y_pos += pixel_value << 6;
    }
    if ( format & HB_GPOS_FORMAT_HAVE_X_ADVANCE_DEVICE )
    {
      _HB_OPEN_Get_Device( &vr->XAdvanceDevice, x_ppem, &pixel_value );
      gd->x_advance += pixel_value << 6;
    }
    if ( format & HB_GPOS_FORMAT_HAVE_Y_ADVANCE_DEVICE )
    {
      _HB_OPEN_Get_Device( &vr->YAdvanceDevice, y_ppem, &pixel_value );
      gd->y_advance += pixel_value << 6;
    }
  }

  /* values returned from mmfunc() are already in fractional pixels */

  if ( format & HB_GPOS_FORMAT_HAVE_X_ID_PLACEMENT )
  {
    error = (gpos->mmfunc)( gpi->face, vr->XIdPlacement,
			    &value, gpos->data );
    if ( error )
      return error;
    gd->x_pos += value;
  }
  if ( format & HB_GPOS_FORMAT_HAVE_Y_ID_PLACEMENT )
  {
    error = (gpos->mmfunc)( gpi->face, vr->YIdPlacement,
			    &value, gpos->data );
    if ( error )
      return error;
    gd->y_pos += value;
  }
  if ( format & HB_GPOS_FORMAT_HAVE_X_ID_ADVANCE )
  {
    error = (gpos->mmfunc)( gpi->face, vr->XIdAdvance,
			    &value, gpos->data );
    if ( error )
      return error;
    gd->x_advance += value;
  }
  if ( format & HB_GPOS_FORMAT_HAVE_Y_ID_ADVANCE )
  {
    error = (gpos->mmfunc)( gpi->face, vr->YIdAdvance,
			    &value, gpos->data );
    if ( error )
      return error;
    gd->y_advance += value;
  }

  return error;
}


/* AnchorFormat1 */
/* AnchorFormat2 */
/* AnchorFormat3 */
/* AnchorFormat4 */

static HB_Error  Load_Anchor( HB_Anchor*  an,
			      FT_Stream    stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_ULong cur_offset, new_offset, base_offset;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 2L ) )
    return error;

  an->PosFormat = GET_UShort();

  FORGET_Frame();

  switch ( an->PosFormat )
  {
  case 1:
    if ( ACCESS_Frame( 4L ) )
      return error;

    an->af.af1.XCoordinate = GET_Short();
    an->af.af1.YCoordinate = GET_Short();

    FORGET_Frame();
    break;

  case 2:
    if ( ACCESS_Frame( 6L ) )
      return error;

    an->af.af2.XCoordinate = GET_Short();
    an->af.af2.YCoordinate = GET_Short();
    an->af.af2.AnchorPoint = GET_UShort();

    FORGET_Frame();
    break;

  case 3:
    if ( ACCESS_Frame( 6L ) )
      return error;

    an->af.af3.XCoordinate = GET_Short();
    an->af.af3.YCoordinate = GET_Short();

    new_offset = GET_UShort();

    FORGET_Frame();

    if ( new_offset )
    {
      new_offset += base_offset;

      cur_offset = FILE_Pos();
      if ( FILE_Seek( new_offset ) ||
	   ( error = _HB_OPEN_Load_Device( &an->af.af3.XDeviceTable,
				  stream ) ) != HB_Err_Ok )
	return error;
      (void)FILE_Seek( cur_offset );
    }
    else
    {
      an->af.af3.XDeviceTable.StartSize  = 0;
      an->af.af3.XDeviceTable.EndSize    = 0;
      an->af.af3.XDeviceTable.DeltaValue = NULL;
    }

    if ( ACCESS_Frame( 2L ) )
      goto Fail;

    new_offset = GET_UShort();

    FORGET_Frame();

    if ( new_offset )
    {
      new_offset += base_offset;

      cur_offset = FILE_Pos();
      if ( FILE_Seek( new_offset ) ||
	   ( error = _HB_OPEN_Load_Device( &an->af.af3.YDeviceTable,
				  stream ) ) != HB_Err_Ok )
	goto Fail;
      (void)FILE_Seek( cur_offset );
    }
    else
    {
      an->af.af3.YDeviceTable.StartSize  = 0;
      an->af.af3.YDeviceTable.EndSize    = 0;
      an->af.af3.YDeviceTable.DeltaValue = NULL;
    }
    break;

  case 4:
    if ( ACCESS_Frame( 4L ) )
      return error;

    an->af.af4.XIdAnchor = GET_UShort();
    an->af.af4.YIdAnchor = GET_UShort();

    FORGET_Frame();
    break;

  default:
    return _hb_err(HB_Err_Invalid_GPOS_SubTable_Format);
  }

  return HB_Err_Ok;

Fail:
  _HB_OPEN_Free_Device( &an->af.af3.XDeviceTable, memory );
  return error;
}


static void  Free_Anchor( HB_Anchor*  an,
			  FT_Memory    memory)
{
  if ( an->PosFormat == 3 )
  {
    _HB_OPEN_Free_Device( &an->af.af3.YDeviceTable, memory );
    _HB_OPEN_Free_Device( &an->af.af3.XDeviceTable, memory );
  }
}


static HB_Error  Get_Anchor( GPOS_Instance*   gpi,
			     HB_Anchor*      an,
			     FT_UShort        glyph_index,
			     FT_Pos*          x_value,
			     FT_Pos*          y_value )
{
  HB_Error  error = HB_Err_Ok;

  FT_Outline       outline;
  HB_GPOSHeader*  gpos = gpi->gpos;
  FT_UShort        ap;

  FT_Short         pixel_value;
  FT_UShort        load_flags;

  FT_UShort        x_ppem, y_ppem;
  FT_Fixed         x_scale, y_scale;


  x_ppem  = gpi->face->size->metrics.x_ppem;
  y_ppem  = gpi->face->size->metrics.y_ppem;
  x_scale = gpi->face->size->metrics.x_scale;
  y_scale = gpi->face->size->metrics.y_scale;

  switch ( an->PosFormat )
  {
  case 0:
    /* The special case of an empty AnchorTable */
  default:

    return HB_Err_Not_Covered;

  case 1:
    *x_value = x_scale * an->af.af1.XCoordinate / 0x10000;
    *y_value = y_scale * an->af.af1.YCoordinate / 0x10000;
    break;

  case 2:
    /* glyphs must be scaled */

    load_flags = gpi->load_flags & ~FT_LOAD_NO_SCALE;

    if ( !gpi->dvi )
    {
      error = (gpos->gfunc)( gpi->face, glyph_index, load_flags );
      if ( error )
	return error;

      if ( gpi->face->glyph->format != ft_glyph_format_outline )
	return _hb_err(HB_Err_Invalid_GPOS_SubTable);

      ap = an->af.af2.AnchorPoint;

      outline = gpi->face->glyph->outline;

      /* if outline.n_points is set to zero by gfunc(), we use the
	 design coordinate value pair.  This can happen e.g. for
	 sbit glyphs                                               */

      if ( !outline.n_points )
	goto no_contour_point;

      if ( ap >= outline.n_points )
	return _hb_err(HB_Err_Invalid_GPOS_SubTable);

      *x_value = outline.points[ap].x;
      *y_value = outline.points[ap].y;
    }
    else
    {
    no_contour_point:
      *x_value = x_scale * an->af.af3.XCoordinate / 0x10000;
      *y_value = y_scale * an->af.af3.YCoordinate / 0x10000;
    }
    break;

  case 3:
    if ( !gpi->dvi )
    {
      _HB_OPEN_Get_Device( &an->af.af3.XDeviceTable, x_ppem, &pixel_value );
      *x_value = pixel_value << 6;
      _HB_OPEN_Get_Device( &an->af.af3.YDeviceTable, y_ppem, &pixel_value );
      *y_value = pixel_value << 6;
    }
    else
      *x_value = *y_value = 0;

    *x_value += x_scale * an->af.af3.XCoordinate / 0x10000;
    *y_value += y_scale * an->af.af3.YCoordinate / 0x10000;
    break;

  case 4:
    error = (gpos->mmfunc)( gpi->face, an->af.af4.XIdAnchor,
			    x_value, gpos->data );
    if ( error )
      return error;

    error = (gpos->mmfunc)( gpi->face, an->af.af4.YIdAnchor,
			    y_value, gpos->data );
    if ( error )
      return error;
    break;
  }

  return error;
}


/* MarkArray */

static HB_Error  Load_MarkArray ( HB_MarkArray*  ma,
				  FT_Stream       stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort        n, m, count;
  FT_ULong         cur_offset, new_offset, base_offset;

  HB_MarkRecord*  mr;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 2L ) )
    return error;

  count = ma->MarkCount = GET_UShort();

  FORGET_Frame();

  ma->MarkRecord = NULL;

  if ( ALLOC_ARRAY( ma->MarkRecord, count, HB_MarkRecord ) )
    return error;

  mr = ma->MarkRecord;

  for ( n = 0; n < count; n++ )
  {
    if ( ACCESS_Frame( 4L ) )
      goto Fail;

    mr[n].Class = GET_UShort();
    new_offset  = GET_UShort() + base_offset;

    FORGET_Frame();

    cur_offset = FILE_Pos();
    if ( FILE_Seek( new_offset ) ||
	 ( error = Load_Anchor( &mr[n].MarkAnchor, stream ) ) != HB_Err_Ok )
      goto Fail;
    (void)FILE_Seek( cur_offset );
  }

  return HB_Err_Ok;

Fail:
  for ( m = 0; m < n; m++ )
    Free_Anchor( &mr[m].MarkAnchor, memory );

  FREE( mr );
  return error;
}


static void  Free_MarkArray( HB_MarkArray*  ma,
			     FT_Memory       memory )
{
  FT_UShort        n, count;

  HB_MarkRecord*  mr;


  if ( ma->MarkRecord )
  {
    count = ma->MarkCount;
    mr    = ma->MarkRecord;

    for ( n = 0; n < count; n++ )
      Free_Anchor( &mr[n].MarkAnchor, memory );

    FREE( mr );
  }
}


/* LookupType 1 */

/* SinglePosFormat1 */
/* SinglePosFormat2 */

static HB_Error  Load_SinglePos( HB_GPOS_SubTable* st,
				 FT_Stream       stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;
  HB_SinglePos*   sp = &st->single;

  FT_UShort         n, m, count, format;
  FT_ULong          cur_offset, new_offset, base_offset;

  HB_ValueRecord*  vr;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 6L ) )
    return error;

  sp->PosFormat = GET_UShort();
  new_offset    = GET_UShort() + base_offset;

  format = sp->ValueFormat = GET_UShort();

  FORGET_Frame();

  if ( !format )
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_Coverage( &sp->Coverage, stream ) ) != HB_Err_Ok )
    return error;
  (void)FILE_Seek( cur_offset );

  switch ( sp->PosFormat )
  {
  case 1:
    error = Load_ValueRecord( &sp->spf.spf1.Value, format,
			      base_offset, stream );
    if ( error )
      goto Fail2;
    break;

  case 2:
    if ( ACCESS_Frame( 2L ) )
      goto Fail2;

    count = sp->spf.spf2.ValueCount = GET_UShort();

    FORGET_Frame();

    sp->spf.spf2.Value = NULL;

    if ( ALLOC_ARRAY( sp->spf.spf2.Value, count, HB_ValueRecord ) )
      goto Fail2;

    vr = sp->spf.spf2.Value;

    for ( n = 0; n < count; n++ )
    {
      error = Load_ValueRecord( &vr[n], format, base_offset, stream );
      if ( error )
	goto Fail1;
    }
    break;

  default:
    return _hb_err(HB_Err_Invalid_GPOS_SubTable_Format);
  }

  return HB_Err_Ok;

Fail1:
  for ( m = 0; m < n; m++ )
    Free_ValueRecord( &vr[m], format, memory );

  FREE( vr );

Fail2:
  _HB_OPEN_Free_Coverage( &sp->Coverage, memory );
  return error;
}


static void  Free_SinglePos( HB_GPOS_SubTable* st,
			     FT_Memory       memory )
{
  FT_UShort         n, count, format;
  HB_SinglePos*   sp = &st->single;

  HB_ValueRecord*  v;


  format = sp->ValueFormat;

  switch ( sp->PosFormat )
  {
  case 1:
    Free_ValueRecord( &sp->spf.spf1.Value, format, memory );
    break;

  case 2:
    if ( sp->spf.spf2.Value )
    {
      count = sp->spf.spf2.ValueCount;
      v     = sp->spf.spf2.Value;

      for ( n = 0; n < count; n++ )
	Free_ValueRecord( &v[n], format, memory );

      FREE( v );
    }
    break;
  default:
    break;
  }

  _HB_OPEN_Free_Coverage( &sp->Coverage, memory );
}

static HB_Error  Lookup_SinglePos( GPOS_Instance*    gpi,
				   HB_GPOS_SubTable* st,
				   HB_Buffer        buffer,
				   FT_UShort         flags,
				   FT_UShort         context_length,
				   int               nesting_level )
{
  FT_UShort        index, property;
  HB_Error         error;
  HB_GPOSHeader*  gpos = gpi->gpos;
  HB_SinglePos*   sp = &st->single;

  FT_UNUSED(nesting_level);

  if ( context_length != 0xFFFF && context_length < 1 )
    return HB_Err_Not_Covered;

  if ( CHECK_Property( gpos->gdef, IN_CURITEM(), flags, &property ) )
    return error;

  error = _HB_OPEN_Coverage_Index( &sp->Coverage, IN_CURGLYPH(), &index );
  if ( error )
    return error;

  switch ( sp->PosFormat )
  {
  case 1:
    error = Get_ValueRecord( gpi, &sp->spf.spf1.Value,
			     sp->ValueFormat, POSITION( buffer->in_pos ) );
    if ( error )
      return error;
    break;

  case 2:
    if ( index >= sp->spf.spf2.ValueCount )
      return _hb_err(HB_Err_Invalid_GPOS_SubTable);
    error = Get_ValueRecord( gpi, &sp->spf.spf2.Value[index],
			     sp->ValueFormat, POSITION( buffer->in_pos ) );
    if ( error )
      return error;
    break;

  default:
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);
  }

  (buffer->in_pos)++;

  return HB_Err_Ok;
}


/* LookupType 2 */

/* PairSet */

static HB_Error  Load_PairSet ( HB_PairSet*  ps,
				FT_UShort     format1,
				FT_UShort     format2,
				FT_Stream     stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort             n, m, count;
  FT_ULong              base_offset;

  HB_PairValueRecord*  pvr;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 2L ) )
    return error;

  count = ps->PairValueCount = GET_UShort();

  FORGET_Frame();

  ps->PairValueRecord = NULL;

  if ( ALLOC_ARRAY( ps->PairValueRecord, count, HB_PairValueRecord ) )
    return error;

  pvr = ps->PairValueRecord;

  for ( n = 0; n < count; n++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail;

    pvr[n].SecondGlyph = GET_UShort();

    FORGET_Frame();

    if ( format1 )
    {
      error = Load_ValueRecord( &pvr[n].Value1, format1,
				base_offset, stream );
      if ( error )
	goto Fail;
    }
    if ( format2 )
    {
      error = Load_ValueRecord( &pvr[n].Value2, format2,
				base_offset, stream );
      if ( error )
      {
	if ( format1 )
	  Free_ValueRecord( &pvr[n].Value1, format1, memory );
	goto Fail;
      }
    }
  }

  return HB_Err_Ok;

Fail:
  for ( m = 0; m < n; m++ )
  {
    if ( format1 )
      Free_ValueRecord( &pvr[m].Value1, format1, memory );
    if ( format2 )
      Free_ValueRecord( &pvr[m].Value2, format2, memory );
  }

  FREE( pvr );
  return error;
}


static void  Free_PairSet( HB_PairSet*  ps,
			   FT_UShort     format1,
			   FT_UShort     format2,
			   FT_Memory     memory )
{
  FT_UShort             n, count;

  HB_PairValueRecord*  pvr;


  if ( ps->PairValueRecord )
  {
    count = ps->PairValueCount;
    pvr   = ps->PairValueRecord;

    for ( n = 0; n < count; n++ )
    {
      if ( format1 )
	Free_ValueRecord( &pvr[n].Value1, format1, memory );
      if ( format2 )
	Free_ValueRecord( &pvr[n].Value2, format2, memory );
    }

    FREE( pvr );
  }
}


/* PairPosFormat1 */

static HB_Error  Load_PairPos1( HB_PairPosFormat1*  ppf1,
				FT_UShort            format1,
				FT_UShort            format2,
				FT_Stream            stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort     n, m, count;
  FT_ULong      cur_offset, new_offset, base_offset;

  HB_PairSet*  ps;


  base_offset = FILE_Pos() - 8L;

  if ( ACCESS_Frame( 2L ) )
    return error;

  count = ppf1->PairSetCount = GET_UShort();

  FORGET_Frame();

  ppf1->PairSet = NULL;

  if ( ALLOC_ARRAY( ppf1->PairSet, count, HB_PairSet ) )
    return error;

  ps = ppf1->PairSet;

  for ( n = 0; n < count; n++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    cur_offset = FILE_Pos();
    if ( FILE_Seek( new_offset ) ||
	 ( error = Load_PairSet( &ps[n], format1,
				 format2, stream ) ) != HB_Err_Ok )
      goto Fail;
    (void)FILE_Seek( cur_offset );
  }

  return HB_Err_Ok;

Fail:
  for ( m = 0; m < n; m++ )
    Free_PairSet( &ps[m], format1, format2, memory );

  FREE( ps );
  return error;
}


static void  Free_PairPos1( HB_PairPosFormat1*  ppf1,
			    FT_UShort            format1,
			    FT_UShort            format2,
			    FT_Memory            memory )
{
  FT_UShort     n, count;

  HB_PairSet*  ps;


  if ( ppf1->PairSet )
  {
    count = ppf1->PairSetCount;
    ps    = ppf1->PairSet;

    for ( n = 0; n < count; n++ )
      Free_PairSet( &ps[n], format1, format2, memory );

    FREE( ps );
  }
}


/* PairPosFormat2 */

static HB_Error  Load_PairPos2( HB_PairPosFormat2*  ppf2,
				FT_UShort            format1,
				FT_UShort            format2,
				FT_Stream            stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort          m, n, k, count1, count2;
  FT_ULong           cur_offset, new_offset1, new_offset2, base_offset;

  HB_Class1Record*  c1r;
  HB_Class2Record*  c2r;


  base_offset = FILE_Pos() - 8L;

  if ( ACCESS_Frame( 8L ) )
    return error;

  new_offset1 = GET_UShort() + base_offset;
  new_offset2 = GET_UShort() + base_offset;

  /* `Class1Count' and `Class2Count' are the upper limits for class
     values, thus we read it now to make additional safety checks.  */

  count1 = ppf2->Class1Count = GET_UShort();
  count2 = ppf2->Class2Count = GET_UShort();

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset1 ) ||
       ( error = _HB_OPEN_Load_ClassDefinition( &ppf2->ClassDef1, count1,
				       stream ) ) != HB_Err_Ok )
    return error;
  if ( FILE_Seek( new_offset2 ) ||
       ( error = _HB_OPEN_Load_ClassDefinition( &ppf2->ClassDef2, count2,
				       stream ) ) != HB_Err_Ok )
    goto Fail3;
  (void)FILE_Seek( cur_offset );

  ppf2->Class1Record = NULL;

  if ( ALLOC_ARRAY( ppf2->Class1Record, count1, HB_Class1Record ) )
    goto Fail2;

  c1r = ppf2->Class1Record;

  for ( m = 0; m < count1; m++ )
  {
    c1r[m].Class2Record = NULL;

    if ( ALLOC_ARRAY( c1r[m].Class2Record, count2, HB_Class2Record ) )
      goto Fail1;

    c2r = c1r[m].Class2Record;

    for ( n = 0; n < count2; n++ )
    {
      if ( format1 )
      {
	error = Load_ValueRecord( &c2r[n].Value1, format1,
				  base_offset, stream );
	if ( error )
	  goto Fail0;
      }
      if ( format2 )
      {
	error = Load_ValueRecord( &c2r[n].Value2, format2,
				  base_offset, stream );
	if ( error )
	{
	  if ( format1 )
	    Free_ValueRecord( &c2r[n].Value1, format1, memory );
	  goto Fail0;
	}
      }
    }

    continue;

  Fail0:
    for ( k = 0; k < n; k++ )
    {
      if ( format1 )
	Free_ValueRecord( &c2r[k].Value1, format1, memory );
      if ( format2 )
	Free_ValueRecord( &c2r[k].Value2, format2, memory );
    }
    goto Fail1;
  }

  return HB_Err_Ok;

Fail1:
  for ( k = 0; k < m; k++ )
  {
    c2r = c1r[k].Class2Record;

    for ( n = 0; n < count2; n++ )
    {
      if ( format1 )
	Free_ValueRecord( &c2r[n].Value1, format1, memory );
      if ( format2 )
	Free_ValueRecord( &c2r[n].Value2, format2, memory );
    }

    FREE( c2r );
  }

  FREE( c1r );
Fail2:

  _HB_OPEN_Free_ClassDefinition( &ppf2->ClassDef2, memory );

Fail3:
  _HB_OPEN_Free_ClassDefinition( &ppf2->ClassDef1, memory );
  return error;
}


static void  Free_PairPos2( HB_PairPosFormat2*  ppf2,
			    FT_UShort            format1,
			    FT_UShort            format2,
			    FT_Memory            memory )
{
  FT_UShort          m, n, count1, count2;

  HB_Class1Record*  c1r;
  HB_Class2Record*  c2r;


  if ( ppf2->Class1Record )
  {
    c1r    = ppf2->Class1Record;
    count1 = ppf2->Class1Count;
    count2 = ppf2->Class2Count;

    for ( m = 0; m < count1; m++ )
    {
      c2r = c1r[m].Class2Record;

      for ( n = 0; n < count2; n++ )
      {
	if ( format1 )
	  Free_ValueRecord( &c2r[n].Value1, format1, memory );
	if ( format2 )
	  Free_ValueRecord( &c2r[n].Value2, format2, memory );
      }

      FREE( c2r );
    }

    FREE( c1r );

    _HB_OPEN_Free_ClassDefinition( &ppf2->ClassDef2, memory );
    _HB_OPEN_Free_ClassDefinition( &ppf2->ClassDef1, memory );
  }
}


static HB_Error  Load_PairPos( HB_GPOS_SubTable* st,
			       FT_Stream     stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;
  HB_PairPos*     pp = &st->pair;

  FT_UShort         format1, format2;
  FT_ULong          cur_offset, new_offset, base_offset;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 8L ) )
    return error;

  pp->PosFormat = GET_UShort();
  new_offset    = GET_UShort() + base_offset;

  format1 = pp->ValueFormat1 = GET_UShort();
  format2 = pp->ValueFormat2 = GET_UShort();

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_Coverage( &pp->Coverage, stream ) ) != HB_Err_Ok )
    return error;
  (void)FILE_Seek( cur_offset );

  switch ( pp->PosFormat )
  {
  case 1:
    error = Load_PairPos1( &pp->ppf.ppf1, format1, format2, stream );
    if ( error )
      goto Fail;
    break;

  case 2:
    error = Load_PairPos2( &pp->ppf.ppf2, format1, format2, stream );
    if ( error )
      goto Fail;
    break;

  default:
    return _hb_err(HB_Err_Invalid_GPOS_SubTable_Format);
  }

  return HB_Err_Ok;

Fail:
  _HB_OPEN_Free_Coverage( &pp->Coverage, memory );
  return error;
}


static void  Free_PairPos( HB_GPOS_SubTable* st,
			   FT_Memory     memory )
{
  FT_UShort  format1, format2;
  HB_PairPos*     pp = &st->pair;


  format1 = pp->ValueFormat1;
  format2 = pp->ValueFormat2;

  switch ( pp->PosFormat )
  {
  case 1:
    Free_PairPos1( &pp->ppf.ppf1, format1, format2, memory );
    break;

  case 2:
    Free_PairPos2( &pp->ppf.ppf2, format1, format2, memory );
    break;

  default:
    break;
  }

  _HB_OPEN_Free_Coverage( &pp->Coverage, memory );
}


static HB_Error  Lookup_PairPos1( GPOS_Instance*       gpi,
				  HB_PairPosFormat1*  ppf1,
				  HB_Buffer           buffer,
				  FT_ULong             first_pos,
				  FT_UShort            index,
				  FT_UShort            format1,
				  FT_UShort            format2 )
{
  HB_Error              error;
  FT_UShort             numpvr, glyph2;

  HB_PairValueRecord*  pvr;


  if ( index >= ppf1->PairSetCount )
     return _hb_err(HB_Err_Invalid_GPOS_SubTable);

  pvr = ppf1->PairSet[index].PairValueRecord;
  if ( !pvr )
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);

  glyph2 = IN_CURGLYPH();

  for ( numpvr = ppf1->PairSet[index].PairValueCount;
	numpvr;
	numpvr--, pvr++ )
  {
    if ( glyph2 == pvr->SecondGlyph )
    {
      error = Get_ValueRecord( gpi, &pvr->Value1, format1,
			       POSITION( first_pos ) );
      if ( error )
	return error;
      return Get_ValueRecord( gpi, &pvr->Value2, format2,
			      POSITION( buffer->in_pos ) );
    }
  }

  return HB_Err_Not_Covered;
}


static HB_Error  Lookup_PairPos2( GPOS_Instance*       gpi,
				  HB_PairPosFormat2*  ppf2,
				  HB_Buffer           buffer,
				  FT_ULong             first_pos,
				  FT_UShort            format1,
				  FT_UShort            format2 )
{
  HB_Error           error;
  FT_UShort          cl1, cl2;

  HB_Class1Record*  c1r;
  HB_Class2Record*  c2r;


  error = _HB_OPEN_Get_Class( &ppf2->ClassDef1, IN_GLYPH( first_pos ),
		     &cl1, NULL );
  if ( error && error != HB_Err_Not_Covered )
    return error;
  error = _HB_OPEN_Get_Class( &ppf2->ClassDef2, IN_CURGLYPH(),
		     &cl2, NULL );
  if ( error && error != HB_Err_Not_Covered )
    return error;

  c1r = &ppf2->Class1Record[cl1];
  if ( !c1r )
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);
  c2r = &c1r->Class2Record[cl2];

  error = Get_ValueRecord( gpi, &c2r->Value1, format1, POSITION( first_pos ) );
  if ( error )
    return error;
  return Get_ValueRecord( gpi, &c2r->Value2, format2, POSITION( buffer->in_pos ) );
}


static HB_Error  Lookup_PairPos( GPOS_Instance*    gpi,
				 HB_GPOS_SubTable* st,
				 HB_Buffer        buffer,
				 FT_UShort         flags,
				 FT_UShort         context_length,
				 int               nesting_level )
{
  HB_Error         error;
  FT_UShort        index, property;
  FT_ULong         first_pos;
  HB_GPOSHeader*  gpos = gpi->gpos;
  HB_PairPos*     pp = &st->pair;

  FT_UNUSED(nesting_level);

  if ( buffer->in_pos >= buffer->in_length - 1 )
    return HB_Err_Not_Covered;           /* Not enough glyphs in stream */

  if ( context_length != 0xFFFF && context_length < 2 )
    return HB_Err_Not_Covered;

  if ( CHECK_Property( gpos->gdef, IN_CURITEM(), flags, &property ) )
    return error;

  error = _HB_OPEN_Coverage_Index( &pp->Coverage, IN_CURGLYPH(), &index );
  if ( error )
    return error;

  /* second glyph */

  first_pos = buffer->in_pos;
  (buffer->in_pos)++;

  while ( CHECK_Property( gpos->gdef, IN_CURITEM(),
			  flags, &property ) )
  {
    if ( error && error != HB_Err_Not_Covered )
      return error;

    if ( buffer->in_pos == buffer->in_length )
      {
	buffer->in_pos = first_pos;
        return HB_Err_Not_Covered;
      }
    (buffer->in_pos)++;

  }

  switch ( pp->PosFormat )
  {
  case 1:
    error = Lookup_PairPos1( gpi, &pp->ppf.ppf1, buffer,
			     first_pos, index,
			     pp->ValueFormat1, pp->ValueFormat2 );
    break;

  case 2:
    error = Lookup_PairPos2( gpi, &pp->ppf.ppf2, buffer, first_pos,
			     pp->ValueFormat1, pp->ValueFormat2 );
    break;

  default:
    return _hb_err(HB_Err_Invalid_GPOS_SubTable_Format);
  }

  /* if we don't have coverage for the second glyph don't skip it for
     further lookups but reset in_pos back to the first_glyph and let
     the caller in Do_String_Lookup increment in_pos */
  if ( error == HB_Err_Not_Covered )
      buffer->in_pos = first_pos;

  /* adjusting the `next' glyph */

  if ( pp->ValueFormat2 )
    (buffer->in_pos)++;

  return error;
}


/* LookupType 3 */

/* CursivePosFormat1 */

static HB_Error  Load_CursivePos( HB_GPOS_SubTable* st,
				  FT_Stream        stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;
  HB_CursivePos*  cp = &st->cursive;

  FT_UShort             n, m, count;
  FT_ULong              cur_offset, new_offset, base_offset;

  HB_EntryExitRecord*  eer;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 4L ) )
    return error;

  cp->PosFormat = GET_UShort();
  new_offset    = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_Coverage( &cp->Coverage, stream ) ) != HB_Err_Ok )
    return error;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 2L ) )
    goto Fail2;

  count = cp->EntryExitCount = GET_UShort();

  FORGET_Frame();

  cp->EntryExitRecord = NULL;

  if ( ALLOC_ARRAY( cp->EntryExitRecord, count, HB_EntryExitRecord ) )
    goto Fail2;

  eer = cp->EntryExitRecord;

  for ( n = 0; n < count; n++ )
  {
    FT_ULong entry_offset;

    if ( ACCESS_Frame( 2L ) )
      return error;

    entry_offset = new_offset = GET_UShort();

    FORGET_Frame();

    if ( new_offset )
    {
      new_offset += base_offset;

      cur_offset = FILE_Pos();
      if ( FILE_Seek( new_offset ) ||
	   ( error = Load_Anchor( &eer[n].EntryAnchor,
				  stream ) ) != HB_Err_Ok )
	goto Fail1;
      (void)FILE_Seek( cur_offset );
    }
    else
      eer[n].EntryAnchor.PosFormat   = 0;

    if ( ACCESS_Frame( 2L ) )
      return error;

    new_offset = GET_UShort();

    FORGET_Frame();

    if ( new_offset )
    {
      new_offset += base_offset;

      cur_offset = FILE_Pos();
      if ( FILE_Seek( new_offset ) ||
	   ( error = Load_Anchor( &eer[n].ExitAnchor,
				  stream ) ) != HB_Err_Ok )
      {
	if ( entry_offset )
	  Free_Anchor( &eer[n].EntryAnchor, memory );
	goto Fail1;
      }
      (void)FILE_Seek( cur_offset );
    }
    else
      eer[n].ExitAnchor.PosFormat   = 0;
  }

  return HB_Err_Ok;

Fail1:
  for ( m = 0; m < n; m++ )
  {
    Free_Anchor( &eer[m].EntryAnchor, memory );
    Free_Anchor( &eer[m].ExitAnchor, memory );
  }

  FREE( eer );

Fail2:
  _HB_OPEN_Free_Coverage( &cp->Coverage, memory );
  return error;
}


static void  Free_CursivePos( HB_GPOS_SubTable* st,
			      FT_Memory        memory )
{
  FT_UShort             n, count;
  HB_CursivePos*  cp = &st->cursive;

  HB_EntryExitRecord*  eer;


  if ( cp->EntryExitRecord )
  {
    count = cp->EntryExitCount;
    eer   = cp->EntryExitRecord;

    for ( n = 0; n < count; n++ )
    {
      Free_Anchor( &eer[n].EntryAnchor, memory );
      Free_Anchor( &eer[n].ExitAnchor, memory );
    }

    FREE( eer );
  }

  _HB_OPEN_Free_Coverage( &cp->Coverage, memory );
}


static HB_Error  Lookup_CursivePos( GPOS_Instance*    gpi,
				    HB_GPOS_SubTable* st,
				    HB_Buffer        buffer,
				    FT_UShort         flags,
				    FT_UShort         context_length,
				    int               nesting_level )
{
  FT_UShort        index, property;
  HB_Error         error;
  HB_GPOSHeader*  gpos = gpi->gpos;
  HB_CursivePos*  cp = &st->cursive;

  HB_EntryExitRecord*  eer;
  FT_Pos                entry_x, entry_y;
  FT_Pos                exit_x, exit_y;

  FT_UNUSED(nesting_level);

  if ( context_length != 0xFFFF && context_length < 1 )
  {
    gpi->last = 0xFFFF;
    return HB_Err_Not_Covered;
  }

  /* Glyphs not having the right GDEF properties will be ignored, i.e.,
     gpi->last won't be reset (contrary to user defined properties). */

  if ( CHECK_Property( gpos->gdef, IN_CURITEM(), flags, &property ) )
    return error;

  /* We don't handle mark glyphs here.  According to Andrei, this isn't
     possible, but who knows...                                         */

  if ( property == HB_GDEF_MARK )
  {
    gpi->last = 0xFFFF;
    return HB_Err_Not_Covered;
  }

  error = _HB_OPEN_Coverage_Index( &cp->Coverage, IN_CURGLYPH(), &index );
  if ( error )
  {
    gpi->last = 0xFFFF;
    return error;
  }

  if ( index >= cp->EntryExitCount )
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);

  eer = &cp->EntryExitRecord[index];

  /* Now comes the messiest part of the whole OpenType
     specification.  At first glance, cursive connections seem easy
     to understand, but there are pitfalls!  The reason is that
     the specs don't mention how to compute the advance values
     resp. glyph offsets.  I was told it would be an omission, to
     be fixed in the next OpenType version...  Again many thanks to
     Andrei Burago <andreib@microsoft.com> for clarifications.

     Consider the following example:

		      |  xadv1    |
		       +---------+
		       |         |
		 +-----+--+ 1    |
		 |     | .|      |
		 |    0+--+------+
		 |   2    |
		 |        |
		0+--------+
		|  xadv2   |

       glyph1: advance width = 12
	       anchor point = (3,1)

       glyph2: advance width = 11
	       anchor point = (9,4)

       LSB is 1 for both glyphs (so the boxes drawn above are glyph
       bboxes).  Writing direction is R2L; `0' denotes the glyph's
       coordinate origin.

     Now the surprising part: The advance width of the *left* glyph
     (resp. of the *bottom* glyph) will be modified, no matter
     whether the writing direction is L2R or R2L (resp. T2B or
     B2T)!  This assymetry is caused by the fact that the glyph's
     coordinate origin is always the lower left corner for all
     writing directions.

     Continuing the above example, we can compute the new
     (horizontal) advance width of glyph2 as

       9 - 3 = 6  ,

     and the new vertical offset of glyph2 as

       1 - 4 = -3  .


     Vertical writing direction is far more complicated:

     a) Assuming that we recompute the advance height of the lower glyph:

				  --
		       +---------+
	      --       |         |
		 +-----+--+ 1    | yadv1
		 |     | .|      |
	   yadv2 |    0+--+------+        -- BSB1  --
		 |   2    |       --      --        y_offset
		 |        |
   BSB2 --      0+--------+                        --
	--    --

       glyph1: advance height = 6
	       anchor point = (3,1)

       glyph2: advance height = 7
	       anchor point = (9,4)

       TSB is 1 for both glyphs; writing direction is T2B.


	 BSB1     = yadv1 - (TSB1 + ymax1)
	 BSB2     = yadv2 - (TSB2 + ymax2)
	 y_offset = y2 - y1

       vertical advance width of glyph2
	 = y_offset + BSB2 - BSB1
	 = (y2 - y1) + (yadv2 - (TSB2 + ymax2)) - (yadv1 - (TSB1 + ymax1))
	 = y2 - y1 + yadv2 - TSB2 - ymax2 - (yadv1 - TSB1 - ymax1)
	 = y2 - y1 + yadv2 - TSB2 - ymax2 - yadv1 + TSB1 + ymax1


     b) Assuming that we recompute the advance height of the upper glyph:

				  --      --
		       +---------+        -- TSB1
	--    --       |         |
   TSB2 --       +-----+--+ 1    | yadv1   ymax1
		 |     | .|      |
	   yadv2 |    0+--+------+        --       --
    ymax2        |   2    |       --                y_offset
		 |        |
	--      0+--------+                        --
	      --

       glyph1: advance height = 6
	       anchor point = (3,1)

       glyph2: advance height = 7
	       anchor point = (9,4)

       TSB is 1 for both glyphs; writing direction is T2B.

       y_offset = y2 - y1

       vertical advance width of glyph2
	 = TSB1 + ymax1 + y_offset - (TSB2 + ymax2)
	 = TSB1 + ymax1 + y2 - y1 - TSB2 - ymax2


     Comparing a) with b) shows that b) is easier to compute.  I'll wait
     for a reply from Andrei to see what should really be implemented...

     Since horizontal advance widths or vertical advance heights
     can be used alone but not together, no ambiguity occurs.        */

  if ( gpi->last == 0xFFFF )
    goto end;

  /* Get_Anchor() returns HB_Err_Not_Covered if there is no anchor
     table.                                                         */

  error = Get_Anchor( gpi, &eer->EntryAnchor, IN_CURGLYPH(),
		      &entry_x, &entry_y );
  if ( error == HB_Err_Not_Covered )
    goto end;
  if ( error )
    return error;

  if ( gpi->r2l )
  {
    POSITION( buffer->in_pos )->x_advance   = entry_x - gpi->anchor_x;
    POSITION( buffer->in_pos )->new_advance = TRUE;
  }
  else
  {
    POSITION( gpi->last )->x_advance   = gpi->anchor_x - entry_x;
    POSITION( gpi->last )->new_advance = TRUE;
  }

  if ( flags & HB_LOOKUP_FLAG_RIGHT_TO_LEFT )
  {
    POSITION( gpi->last )->cursive_chain = gpi->last - buffer->in_pos;
    POSITION( gpi->last )->y_pos = entry_y - gpi->anchor_y;
  }
  else
  {
    POSITION( buffer->in_pos )->cursive_chain = buffer->in_pos - gpi->last;
    POSITION( buffer->in_pos )->y_pos = gpi->anchor_y - entry_y;
  }

end:
  error = Get_Anchor( gpi, &eer->ExitAnchor, IN_CURGLYPH(),
		      &exit_x, &exit_y );
  if ( error == HB_Err_Not_Covered )
    gpi->last = 0xFFFF;
  else
  {
    gpi->last     = buffer->in_pos;
    gpi->anchor_x = exit_x;
    gpi->anchor_y = exit_y;
  }
  if ( error )
    return error;

  (buffer->in_pos)++;

  return HB_Err_Ok;
}


/* LookupType 4 */

/* BaseArray */

static HB_Error  Load_BaseArray( HB_BaseArray*  ba,
				 FT_UShort       num_classes,
				 FT_Stream       stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort        m, n, k, count;
  FT_ULong         cur_offset, new_offset, base_offset;

  HB_BaseRecord*  br;
  HB_Anchor*      ban;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 2L ) )
    return error;

  count = ba->BaseCount = GET_UShort();

  FORGET_Frame();

  ba->BaseRecord = NULL;

  if ( ALLOC_ARRAY( ba->BaseRecord, count, HB_BaseRecord ) )
    return error;

  br = ba->BaseRecord;

  for ( m = 0; m < count; m++ )
  {
    br[m].BaseAnchor = NULL;

    if ( ALLOC_ARRAY( br[m].BaseAnchor, num_classes, HB_Anchor ) )
      goto Fail;

    ban = br[m].BaseAnchor;

    for ( n = 0; n < num_classes; n++ )
    {
      if ( ACCESS_Frame( 2L ) )
	goto Fail0;

      new_offset = GET_UShort() + base_offset;

      FORGET_Frame();

      if (new_offset == base_offset) {
	/* XXX
	 * Doulos SIL Regular is buggy and has zero offsets here.
	 * Skip it
	 */
	ban[n].PosFormat = 0;
	continue;
      }

      cur_offset = FILE_Pos();
      if ( FILE_Seek( new_offset ) ||
	   ( error = Load_Anchor( &ban[n], stream ) ) != HB_Err_Ok )
	goto Fail0;
      (void)FILE_Seek( cur_offset );
    }

    continue;
  Fail0:
    for ( k = 0; k < n; k++ )
      Free_Anchor( &ban[k], memory );
    goto Fail;
  }

  return HB_Err_Ok;

Fail:
  for ( k = 0; k < m; k++ )
  {
    ban = br[k].BaseAnchor;

    for ( n = 0; n < num_classes; n++ )
      Free_Anchor( &ban[n], memory );

    FREE( ban );
  }

  FREE( br );
  return error;
}


static void  Free_BaseArray( HB_BaseArray*  ba,
			     FT_UShort       num_classes,
			     FT_Memory       memory )
{
  FT_UShort        m, n, count;

  HB_BaseRecord*  br;
  HB_Anchor*      ban;


  if ( ba->BaseRecord )
  {
    count = ba->BaseCount;
    br    = ba->BaseRecord;

    for ( m = 0; m < count; m++ )
    {
      ban = br[m].BaseAnchor;

      for ( n = 0; n < num_classes; n++ )
	Free_Anchor( &ban[n], memory );

      FREE( ban );
    }

    FREE( br );
  }
}


/* MarkBasePosFormat1 */

static HB_Error  Load_MarkBasePos( HB_GPOS_SubTable* st,
				   FT_Stream         stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;
  HB_MarkBasePos* mbp = &st->markbase;

  FT_ULong  cur_offset, new_offset, base_offset;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 4L ) )
    return error;

  mbp->PosFormat = GET_UShort();
  new_offset     = GET_UShort() + base_offset;

  FORGET_Frame();

  if (mbp->PosFormat != 1)
    return _hb_err(HB_Err_Invalid_SubTable_Format);

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_Coverage( &mbp->MarkCoverage, stream ) ) != HB_Err_Ok )
    return error;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 2L ) )
    goto Fail3;

  new_offset = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_Coverage( &mbp->BaseCoverage, stream ) ) != HB_Err_Ok )
    goto Fail3;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 4L ) )
    goto Fail2;

  mbp->ClassCount = GET_UShort();
  new_offset      = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = Load_MarkArray( &mbp->MarkArray, stream ) ) != HB_Err_Ok )
    goto Fail2;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 2L ) )
    goto Fail1;

  new_offset = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = Load_BaseArray( &mbp->BaseArray, mbp->ClassCount,
				 stream ) ) != HB_Err_Ok )
    goto Fail1;

  return HB_Err_Ok;

Fail1:
  Free_MarkArray( &mbp->MarkArray, memory );

Fail2:
  _HB_OPEN_Free_Coverage( &mbp->BaseCoverage, memory );

Fail3:
  _HB_OPEN_Free_Coverage( &mbp->MarkCoverage, memory );
  return error;
}


static void  Free_MarkBasePos( HB_GPOS_SubTable* st,
			       FT_Memory         memory )
{
  HB_MarkBasePos* mbp = &st->markbase;

  Free_BaseArray( &mbp->BaseArray, mbp->ClassCount, memory );
  Free_MarkArray( &mbp->MarkArray, memory );
  _HB_OPEN_Free_Coverage( &mbp->BaseCoverage, memory );
  _HB_OPEN_Free_Coverage( &mbp->MarkCoverage, memory );
}


static HB_Error  Lookup_MarkBasePos( GPOS_Instance*    gpi,
				     HB_GPOS_SubTable* st,
				     HB_Buffer        buffer,
				     FT_UShort         flags,
				     FT_UShort         context_length,
				     int               nesting_level )
{
  FT_UShort        i, j, mark_index, base_index, property, class;
  FT_Pos           x_mark_value, y_mark_value, x_base_value, y_base_value;
  HB_Error         error;
  HB_GPOSHeader*  gpos = gpi->gpos;
  HB_MarkBasePos* mbp = &st->markbase;

  HB_MarkArray*   ma;
  HB_BaseArray*   ba;
  HB_BaseRecord*  br;
  HB_Anchor*      mark_anchor;
  HB_Anchor*      base_anchor;

  HB_Position     o;

  FT_UNUSED(nesting_level);

  if ( context_length != 0xFFFF && context_length < 1 )
    return HB_Err_Not_Covered;

  if ( flags & HB_LOOKUP_FLAG_IGNORE_BASE_GLYPHS )
    return HB_Err_Not_Covered;

  if ( CHECK_Property( gpos->gdef, IN_CURITEM(),
		       flags, &property ) )
    return error;

  error = _HB_OPEN_Coverage_Index( &mbp->MarkCoverage, IN_CURGLYPH(),
			  &mark_index );
  if ( error )
    return error;

  /* now we search backwards for a non-mark glyph */

  i = 1;
  j = buffer->in_pos - 1;

  while ( i <= buffer->in_pos )
  {
    error = HB_GDEF_Get_Glyph_Property( gpos->gdef, IN_GLYPH( j ),
					&property );
    if ( error )
      return error;

    if ( !( property == HB_GDEF_MARK || property & HB_LOOKUP_FLAG_IGNORE_SPECIAL_MARKS ) )
      break;

    i++;
    j--;
  }

  /* The following assertion is too strong -- at least for mangal.ttf. */
#if 0
  if ( property != HB_GDEF_BASE_GLYPH )
    return HB_Err_Not_Covered;
#endif

  if ( i > buffer->in_pos )
    return HB_Err_Not_Covered;

  error = _HB_OPEN_Coverage_Index( &mbp->BaseCoverage, IN_GLYPH( j ),
			  &base_index );
  if ( error )
    return error;

  ma = &mbp->MarkArray;

  if ( mark_index >= ma->MarkCount )
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);

  class       = ma->MarkRecord[mark_index].Class;
  mark_anchor = &ma->MarkRecord[mark_index].MarkAnchor;

  if ( class >= mbp->ClassCount )
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);

  ba = &mbp->BaseArray;

  if ( base_index >= ba->BaseCount )
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);

  br          = &ba->BaseRecord[base_index];
  base_anchor = &br->BaseAnchor[class];

  error = Get_Anchor( gpi, mark_anchor, IN_CURGLYPH(),
		      &x_mark_value, &y_mark_value );
  if ( error )
    return error;

  error = Get_Anchor( gpi, base_anchor, IN_GLYPH( j ),
		      &x_base_value, &y_base_value );
  if ( error )
    return error;

  /* anchor points are not cumulative */

  o = POSITION( buffer->in_pos );

  o->x_pos     = x_base_value - x_mark_value;
  o->y_pos     = y_base_value - y_mark_value;
  o->x_advance = 0;
  o->y_advance = 0;
  o->back      = i;

  (buffer->in_pos)++;

  return HB_Err_Ok;
}


/* LookupType 5 */

/* LigatureAttach */

static HB_Error  Load_LigatureAttach( HB_LigatureAttach*  lat,
				      FT_UShort            num_classes,
				      FT_Stream            stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort             m, n, k, count;
  FT_ULong              cur_offset, new_offset, base_offset;

  HB_ComponentRecord*  cr;
  HB_Anchor*           lan;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 2L ) )
    return error;

  count = lat->ComponentCount = GET_UShort();

  FORGET_Frame();

  lat->ComponentRecord = NULL;

  if ( ALLOC_ARRAY( lat->ComponentRecord, count, HB_ComponentRecord ) )
    return error;

  cr = lat->ComponentRecord;

  for ( m = 0; m < count; m++ )
  {
    cr[m].LigatureAnchor = NULL;

    if ( ALLOC_ARRAY( cr[m].LigatureAnchor, num_classes, HB_Anchor ) )
      goto Fail;

    lan = cr[m].LigatureAnchor;

    for ( n = 0; n < num_classes; n++ )
    {
      if ( ACCESS_Frame( 2L ) )
	goto Fail0;

      new_offset = GET_UShort();

      FORGET_Frame();

      if ( new_offset )
      {
	new_offset += base_offset;

	cur_offset = FILE_Pos();
	if ( FILE_Seek( new_offset ) ||
	     ( error = Load_Anchor( &lan[n], stream ) ) != HB_Err_Ok )
	  goto Fail0;
	(void)FILE_Seek( cur_offset );
      }
      else
	lan[n].PosFormat = 0;
    }

    continue;
  Fail0:
    for ( k = 0; k < n; k++ )
      Free_Anchor( &lan[k], memory );
    goto Fail;
  }

  return HB_Err_Ok;

Fail:
  for ( k = 0; k < m; k++ )
  {
    lan = cr[k].LigatureAnchor;

    for ( n = 0; n < num_classes; n++ )
      Free_Anchor( &lan[n], memory );

    FREE( lan );
  }

  FREE( cr );
  return error;
}


static void  Free_LigatureAttach( HB_LigatureAttach*  lat,
				  FT_UShort            num_classes,
				  FT_Memory            memory )
{
  FT_UShort        m, n, count;

  HB_ComponentRecord*  cr;
  HB_Anchor*           lan;


  if ( lat->ComponentRecord )
  {
    count = lat->ComponentCount;
    cr    = lat->ComponentRecord;

    for ( m = 0; m < count; m++ )
    {
      lan = cr[m].LigatureAnchor;

      for ( n = 0; n < num_classes; n++ )
	Free_Anchor( &lan[n], memory );

      FREE( lan );
    }

    FREE( cr );
  }
}


/* LigatureArray */

static HB_Error  Load_LigatureArray( HB_LigatureArray*  la,
				     FT_UShort           num_classes,
				     FT_Stream           stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort            n, m, count;
  FT_ULong             cur_offset, new_offset, base_offset;

  HB_LigatureAttach*  lat;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 2L ) )
    return error;

  count = la->LigatureCount = GET_UShort();

  FORGET_Frame();

  la->LigatureAttach = NULL;

  if ( ALLOC_ARRAY( la->LigatureAttach, count, HB_LigatureAttach ) )
    return error;

  lat = la->LigatureAttach;

  for ( n = 0; n < count; n++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    cur_offset = FILE_Pos();
    if ( FILE_Seek( new_offset ) ||
	 ( error = Load_LigatureAttach( &lat[n], num_classes,
					stream ) ) != HB_Err_Ok )
      goto Fail;
    (void)FILE_Seek( cur_offset );
  }

  return HB_Err_Ok;

Fail:
  for ( m = 0; m < n; m++ )
    Free_LigatureAttach( &lat[m], num_classes, memory );

  FREE( lat );
  return error;
}


static void  Free_LigatureArray( HB_LigatureArray*  la,
				 FT_UShort           num_classes,
				 FT_Memory           memory )
{
  FT_UShort            n, count;

  HB_LigatureAttach*  lat;


  if ( la->LigatureAttach )
  {
    count = la->LigatureCount;
    lat   = la->LigatureAttach;

    for ( n = 0; n < count; n++ )
      Free_LigatureAttach( &lat[n], num_classes, memory );

    FREE( lat );
  }
}


/* MarkLigPosFormat1 */

static HB_Error  Load_MarkLigPos( HB_GPOS_SubTable* st,
				  FT_Stream        stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;
  HB_MarkLigPos*  mlp = &st->marklig;

  FT_ULong  cur_offset, new_offset, base_offset;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 4L ) )
    return error;

  mlp->PosFormat = GET_UShort();
  new_offset     = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_Coverage( &mlp->MarkCoverage, stream ) ) != HB_Err_Ok )
    return error;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 2L ) )
    goto Fail3;

  new_offset = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_Coverage( &mlp->LigatureCoverage,
				stream ) ) != HB_Err_Ok )
    goto Fail3;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 4L ) )
    goto Fail2;

  mlp->ClassCount = GET_UShort();
  new_offset      = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = Load_MarkArray( &mlp->MarkArray, stream ) ) != HB_Err_Ok )
    goto Fail2;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 2L ) )
    goto Fail1;

  new_offset = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = Load_LigatureArray( &mlp->LigatureArray, mlp->ClassCount,
				     stream ) ) != HB_Err_Ok )
    goto Fail1;

  return HB_Err_Ok;

Fail1:
  Free_MarkArray( &mlp->MarkArray, memory );

Fail2:
  _HB_OPEN_Free_Coverage( &mlp->LigatureCoverage, memory );

Fail3:
  _HB_OPEN_Free_Coverage( &mlp->MarkCoverage, memory );
  return error;
}


static void  Free_MarkLigPos( HB_GPOS_SubTable* st,
			      FT_Memory        memory)
{
  HB_MarkLigPos*  mlp = &st->marklig;

  Free_LigatureArray( &mlp->LigatureArray, mlp->ClassCount, memory );
  Free_MarkArray( &mlp->MarkArray, memory );
  _HB_OPEN_Free_Coverage( &mlp->LigatureCoverage, memory );
  _HB_OPEN_Free_Coverage( &mlp->MarkCoverage, memory );
}


static HB_Error  Lookup_MarkLigPos( GPOS_Instance*    gpi,
				    HB_GPOS_SubTable* st,
				    HB_Buffer        buffer,
				    FT_UShort         flags,
				    FT_UShort         context_length,
				    int               nesting_level )
{
  FT_UShort        i, j, mark_index, lig_index, property, class;
  FT_UShort        mark_glyph;
  FT_Pos           x_mark_value, y_mark_value, x_lig_value, y_lig_value;
  HB_Error         error;
  HB_GPOSHeader*  gpos = gpi->gpos;
  HB_MarkLigPos*  mlp = &st->marklig;

  HB_MarkArray*        ma;
  HB_LigatureArray*    la;
  HB_LigatureAttach*   lat;
  HB_ComponentRecord*  cr;
  FT_UShort             comp_index;
  HB_Anchor*           mark_anchor;
  HB_Anchor*           lig_anchor;

  HB_Position    o;

  FT_UNUSED(nesting_level);

  if ( context_length != 0xFFFF && context_length < 1 )
    return HB_Err_Not_Covered;

  if ( flags & HB_LOOKUP_FLAG_IGNORE_LIGATURES )
    return HB_Err_Not_Covered;

  mark_glyph = IN_CURGLYPH();

  if ( CHECK_Property( gpos->gdef, IN_CURITEM(), flags, &property ) )
    return error;

  error = _HB_OPEN_Coverage_Index( &mlp->MarkCoverage, mark_glyph, &mark_index );
  if ( error )
    return error;

  /* now we search backwards for a non-mark glyph */

  i = 1;
  j = buffer->in_pos - 1;

  while ( i <= buffer->in_pos )
  {
    error = HB_GDEF_Get_Glyph_Property( gpos->gdef, IN_GLYPH( j ),
					&property );
    if ( error )
      return error;

    if ( !( property == HB_GDEF_MARK || property & HB_LOOKUP_FLAG_IGNORE_SPECIAL_MARKS ) )
      break;

    i++;
    j--;
  }

  /* Similar to Lookup_MarkBasePos(), I suspect that this assertion is
     too strong, thus it is commented out.                             */
#if 0
  if ( property != HB_GDEF_LIGATURE )
    return HB_Err_Not_Covered;
#endif

  if ( i > buffer->in_pos )
    return HB_Err_Not_Covered;

  error = _HB_OPEN_Coverage_Index( &mlp->LigatureCoverage, IN_GLYPH( j ),
			  &lig_index );
  if ( error )
    return error;

  ma = &mlp->MarkArray;

  if ( mark_index >= ma->MarkCount )
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);

  class       = ma->MarkRecord[mark_index].Class;
  mark_anchor = &ma->MarkRecord[mark_index].MarkAnchor;

  if ( class >= mlp->ClassCount )
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);

  la = &mlp->LigatureArray;

  if ( lig_index >= la->LigatureCount )
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);

  lat = &la->LigatureAttach[lig_index];

  /* We must now check whether the ligature ID of the current mark glyph
     is identical to the ligature ID of the found ligature.  If yes, we
     can directly use the component index.  If not, we attach the mark
     glyph to the last component of the ligature.                        */

  if ( IN_LIGID( j ) == IN_LIGID( buffer->in_pos) )
  {
    comp_index = IN_COMPONENT( buffer->in_pos );
    if ( comp_index >= lat->ComponentCount )
      return HB_Err_Not_Covered;
  }
  else
    comp_index = lat->ComponentCount - 1;

  cr         = &lat->ComponentRecord[comp_index];
  lig_anchor = &cr->LigatureAnchor[class];

  error = Get_Anchor( gpi, mark_anchor, IN_CURGLYPH(),
		      &x_mark_value, &y_mark_value );
  if ( error )
    return error;
  error = Get_Anchor( gpi, lig_anchor, IN_GLYPH( j ),
		      &x_lig_value, &y_lig_value );
  if ( error )
    return error;

  /* anchor points are not cumulative */

  o = POSITION( buffer->in_pos );

  o->x_pos     = x_lig_value - x_mark_value;
  o->y_pos     = y_lig_value - y_mark_value;
  o->x_advance = 0;
  o->y_advance = 0;
  o->back      = i;

  (buffer->in_pos)++;

  return HB_Err_Ok;
}


/* LookupType 6 */

/* Mark2Array */

static HB_Error  Load_Mark2Array( HB_Mark2Array*  m2a,
				  FT_UShort        num_classes,
				  FT_Stream        stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort         k, m, n, count;
  FT_ULong          cur_offset, new_offset, base_offset;

  HB_Mark2Record*  m2r;
  HB_Anchor*       m2an;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 2L ) )
    return error;

  count = m2a->Mark2Count = GET_UShort();

  FORGET_Frame();

  m2a->Mark2Record = NULL;

  if ( ALLOC_ARRAY( m2a->Mark2Record, count, HB_Mark2Record ) )
    return error;

  m2r = m2a->Mark2Record;

  for ( m = 0; m < count; m++ )
  {
    m2r[m].Mark2Anchor = NULL;

    if ( ALLOC_ARRAY( m2r[m].Mark2Anchor, num_classes, HB_Anchor ) )
      goto Fail;

    m2an = m2r[m].Mark2Anchor;

    for ( n = 0; n < num_classes; n++ )
    {
      if ( ACCESS_Frame( 2L ) )
	goto Fail0;

      new_offset = GET_UShort() + base_offset;

      FORGET_Frame();

      cur_offset = FILE_Pos();
      if ( FILE_Seek( new_offset ) ||
	   ( error = Load_Anchor( &m2an[n], stream ) ) != HB_Err_Ok )
	goto Fail0;
      (void)FILE_Seek( cur_offset );
    }

    continue;
  Fail0:
    for ( k = 0; k < n; k++ )
      Free_Anchor( &m2an[k], memory );
    goto Fail;
  }

  return HB_Err_Ok;

Fail:
  for ( k = 0; k < m; k++ )
  {
    m2an = m2r[k].Mark2Anchor;

    for ( n = 0; n < num_classes; n++ )
      Free_Anchor( &m2an[n], memory );

    FREE( m2an );
  }

  FREE( m2r );
  return error;
}


static void  Free_Mark2Array( HB_Mark2Array*  m2a,
			      FT_UShort        num_classes,
			      FT_Memory        memory )
{
  FT_UShort         m, n, count;

  HB_Mark2Record*  m2r;
  HB_Anchor*       m2an;


  if ( m2a->Mark2Record )
  {
    count = m2a->Mark2Count;
    m2r   = m2a->Mark2Record;

    for ( m = 0; m < count; m++ )
    {
      m2an = m2r[m].Mark2Anchor;

      for ( n = 0; n < num_classes; n++ )
	Free_Anchor( &m2an[n], memory );

      FREE( m2an );
    }

    FREE( m2r );
  }
}


/* MarkMarkPosFormat1 */

static HB_Error  Load_MarkMarkPos( HB_GPOS_SubTable* st,
				   FT_Stream         stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;
  HB_MarkMarkPos* mmp = &st->markmark;

  FT_ULong  cur_offset, new_offset, base_offset;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 4L ) )
    return error;

  mmp->PosFormat = GET_UShort();
  new_offset     = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_Coverage( &mmp->Mark1Coverage,
				stream ) ) != HB_Err_Ok )
    return error;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 2L ) )
    goto Fail3;

  new_offset = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_Coverage( &mmp->Mark2Coverage,
				stream ) ) != HB_Err_Ok )
    goto Fail3;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 4L ) )
    goto Fail2;

  mmp->ClassCount = GET_UShort();
  new_offset      = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = Load_MarkArray( &mmp->Mark1Array, stream ) ) != HB_Err_Ok )
    goto Fail2;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 2L ) )
    goto Fail1;

  new_offset = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = Load_Mark2Array( &mmp->Mark2Array, mmp->ClassCount,
				  stream ) ) != HB_Err_Ok )
    goto Fail1;

  return HB_Err_Ok;

Fail1:
  Free_MarkArray( &mmp->Mark1Array, memory );

Fail2:
  _HB_OPEN_Free_Coverage( &mmp->Mark2Coverage, memory );

Fail3:
  _HB_OPEN_Free_Coverage( &mmp->Mark1Coverage, memory );
  return error;
}


static void  Free_MarkMarkPos( HB_GPOS_SubTable* st,
			       FT_Memory         memory)
{
  HB_MarkMarkPos* mmp = &st->markmark;

  Free_Mark2Array( &mmp->Mark2Array, mmp->ClassCount, memory );
  Free_MarkArray( &mmp->Mark1Array, memory );
  _HB_OPEN_Free_Coverage( &mmp->Mark2Coverage, memory );
  _HB_OPEN_Free_Coverage( &mmp->Mark1Coverage, memory );
}


static HB_Error  Lookup_MarkMarkPos( GPOS_Instance*    gpi,
				     HB_GPOS_SubTable* st,
				     HB_Buffer        buffer,
				     FT_UShort         flags,
				     FT_UShort         context_length,
				     int               nesting_level )
{
  FT_UShort        i, j, mark1_index, mark2_index, property, class;
  FT_Pos           x_mark1_value, y_mark1_value,
		   x_mark2_value, y_mark2_value;
  HB_Error         error;
  HB_GPOSHeader*  gpos = gpi->gpos;
  HB_MarkMarkPos* mmp = &st->markmark;

  HB_MarkArray*    ma1;
  HB_Mark2Array*   ma2;
  HB_Mark2Record*  m2r;
  HB_Anchor*       mark1_anchor;
  HB_Anchor*       mark2_anchor;

  HB_Position    o;

  FT_UNUSED(nesting_level);

  if ( context_length != 0xFFFF && context_length < 1 )
    return HB_Err_Not_Covered;

  if ( flags & HB_LOOKUP_FLAG_IGNORE_MARKS )
    return HB_Err_Not_Covered;

  if ( CHECK_Property( gpos->gdef, IN_CURITEM(),
		       flags, &property ) )
    return error;

  error = _HB_OPEN_Coverage_Index( &mmp->Mark1Coverage, IN_CURGLYPH(),
			  &mark1_index );
  if ( error )
    return error;

  /* now we search backwards for a suitable mark glyph until a non-mark
     glyph                                                */

  if ( buffer->in_pos == 0 )
    return HB_Err_Not_Covered;

  i = 1;
  j = buffer->in_pos - 1;
  while ( i <= buffer->in_pos )
  {
    error = HB_GDEF_Get_Glyph_Property( gpos->gdef, IN_GLYPH( j ),
					&property );
    if ( error )
      return error;

    if ( !( property == HB_GDEF_MARK || property & HB_LOOKUP_FLAG_IGNORE_SPECIAL_MARKS ) )
      return HB_Err_Not_Covered;

    if ( flags & HB_LOOKUP_FLAG_IGNORE_SPECIAL_MARKS )
    {
      if ( property == (flags & 0xFF00) )
        break;
    }
    else
      break;

    i++;
    j--;
  }

  error = _HB_OPEN_Coverage_Index( &mmp->Mark2Coverage, IN_GLYPH( j ),
			  &mark2_index );
  if ( error )
    return error;

  ma1 = &mmp->Mark1Array;

  if ( mark1_index >= ma1->MarkCount )
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);

  class        = ma1->MarkRecord[mark1_index].Class;
  mark1_anchor = &ma1->MarkRecord[mark1_index].MarkAnchor;

  if ( class >= mmp->ClassCount )
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);

  ma2 = &mmp->Mark2Array;

  if ( mark2_index >= ma2->Mark2Count )
    return _hb_err(HB_Err_Invalid_GPOS_SubTable);

  m2r          = &ma2->Mark2Record[mark2_index];
  mark2_anchor = &m2r->Mark2Anchor[class];

  error = Get_Anchor( gpi, mark1_anchor, IN_CURGLYPH(),
		      &x_mark1_value, &y_mark1_value );
  if ( error )
    return error;
  error = Get_Anchor( gpi, mark2_anchor, IN_GLYPH( j ),
		      &x_mark2_value, &y_mark2_value );
  if ( error )
    return error;

  /* anchor points are not cumulative */

  o = POSITION( buffer->in_pos );

  o->x_pos     = x_mark2_value - x_mark1_value;
  o->y_pos     = y_mark2_value - y_mark1_value;
  o->x_advance = 0;
  o->y_advance = 0;
  o->back      = 1;

  (buffer->in_pos)++;

  return HB_Err_Ok;
}


/* Do the actual positioning for a context positioning (either format
   7 or 8).  This is only called after we've determined that the stream
   matches the subrule.                                                 */

static HB_Error  Do_ContextPos( GPOS_Instance*        gpi,
				FT_UShort             GlyphCount,
				FT_UShort             PosCount,
				HB_PosLookupRecord*  pos,
				HB_Buffer            buffer,
				int                   nesting_level )
{
  HB_Error  error;
  FT_ULong i, old_pos;


  i = 0;

  while ( i < GlyphCount )
  {
    if ( PosCount && i == pos->SequenceIndex )
    {
      old_pos = buffer->in_pos;

      /* Do a positioning */

      error = GPOS_Do_Glyph_Lookup( gpi, pos->LookupListIndex, buffer,
				    GlyphCount, nesting_level );

      if ( error )
	return error;

      pos++;
      PosCount--;
      i += buffer->in_pos - old_pos;
    }
    else
    {
      i++;
      (buffer->in_pos)++;
    }
  }

  return HB_Err_Ok;
}


/* LookupType 7 */

/* PosRule */

static HB_Error  Load_PosRule( HB_PosRule*  pr,
			       FT_Stream     stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort             n, count;
  FT_UShort*            i;

  HB_PosLookupRecord*  plr;


  if ( ACCESS_Frame( 4L ) )
    return error;

  pr->GlyphCount = GET_UShort();
  pr->PosCount   = GET_UShort();

  FORGET_Frame();

  pr->Input = NULL;

  count = pr->GlyphCount - 1;         /* only GlyphCount - 1 elements */

  if ( ALLOC_ARRAY( pr->Input, count, FT_UShort ) )
    return error;

  i = pr->Input;

  if ( ACCESS_Frame( count * 2L ) )
    goto Fail2;

  for ( n = 0; n < count; n++ )
    i[n] = GET_UShort();

  FORGET_Frame();

  pr->PosLookupRecord = NULL;

  count = pr->PosCount;

  if ( ALLOC_ARRAY( pr->PosLookupRecord, count, HB_PosLookupRecord ) )
    goto Fail2;

  plr = pr->PosLookupRecord;

  if ( ACCESS_Frame( count * 4L ) )
    goto Fail1;

  for ( n = 0; n < count; n++ )
  {
    plr[n].SequenceIndex   = GET_UShort();
    plr[n].LookupListIndex = GET_UShort();
  }

  FORGET_Frame();

  return HB_Err_Ok;

Fail1:
  FREE( plr );

Fail2:
  FREE( i );
  return error;
}


static void  Free_PosRule( HB_PosRule*  pr,
			   FT_Memory     memory )
{
  FREE( pr->PosLookupRecord );
  FREE( pr->Input );
}


/* PosRuleSet */

static HB_Error  Load_PosRuleSet( HB_PosRuleSet*  prs,
				  FT_Stream        stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort     n, m, count;
  FT_ULong      cur_offset, new_offset, base_offset;

  HB_PosRule*  pr;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 2L ) )
    return error;

  count = prs->PosRuleCount = GET_UShort();

  FORGET_Frame();

  prs->PosRule = NULL;

  if ( ALLOC_ARRAY( prs->PosRule, count, HB_PosRule ) )
    return error;

  pr = prs->PosRule;

  for ( n = 0; n < count; n++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    cur_offset = FILE_Pos();
    if ( FILE_Seek( new_offset ) ||
	 ( error = Load_PosRule( &pr[n], stream ) ) != HB_Err_Ok )
      goto Fail;
    (void)FILE_Seek( cur_offset );
  }

  return HB_Err_Ok;

Fail:
  for ( m = 0; m < n; m++ )
    Free_PosRule( &pr[m], memory );

  FREE( pr );
  return error;
}


static void  Free_PosRuleSet( HB_PosRuleSet*  prs,
			      FT_Memory        memory )
{
  FT_UShort     n, count;

  HB_PosRule*  pr;


  if ( prs->PosRule )
  {
    count = prs->PosRuleCount;
    pr    = prs->PosRule;

    for ( n = 0; n < count; n++ )
      Free_PosRule( &pr[n], memory );

    FREE( pr );
  }
}


/* ContextPosFormat1 */

static HB_Error  Load_ContextPos1( HB_ContextPosFormat1*  cpf1,
				   FT_Stream               stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort        n, m, count;
  FT_ULong         cur_offset, new_offset, base_offset;

  HB_PosRuleSet*  prs;


  base_offset = FILE_Pos() - 2L;

  if ( ACCESS_Frame( 2L ) )
    return error;

  new_offset = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_Coverage( &cpf1->Coverage, stream ) ) != HB_Err_Ok )
    return error;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 2L ) )
    goto Fail2;

  count = cpf1->PosRuleSetCount = GET_UShort();

  FORGET_Frame();

  cpf1->PosRuleSet = NULL;

  if ( ALLOC_ARRAY( cpf1->PosRuleSet, count, HB_PosRuleSet ) )
    goto Fail2;

  prs = cpf1->PosRuleSet;

  for ( n = 0; n < count; n++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail1;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    cur_offset = FILE_Pos();
    if ( FILE_Seek( new_offset ) ||
	 ( error = Load_PosRuleSet( &prs[n], stream ) ) != HB_Err_Ok )
      goto Fail1;
    (void)FILE_Seek( cur_offset );
  }

  return HB_Err_Ok;

Fail1:
  for ( m = 0; m < n; m++ )
    Free_PosRuleSet( &prs[m], memory );

  FREE( prs );

Fail2:
  _HB_OPEN_Free_Coverage( &cpf1->Coverage, memory );
  return error;
}


static void  Free_ContextPos1( HB_ContextPosFormat1*  cpf1,
			    FT_Memory               memory )
{
  FT_UShort        n, count;

  HB_PosRuleSet*  prs;


  if ( cpf1->PosRuleSet )
  {
    count = cpf1->PosRuleSetCount;
    prs   = cpf1->PosRuleSet;

    for ( n = 0; n < count; n++ )
      Free_PosRuleSet( &prs[n], memory );

    FREE( prs );
  }

  _HB_OPEN_Free_Coverage( &cpf1->Coverage, memory );
}


/* PosClassRule */

static HB_Error  Load_PosClassRule( HB_ContextPosFormat2*  cpf2,
				    HB_PosClassRule*       pcr,
				    FT_Stream               stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort             n, count;

  FT_UShort*            c;
  HB_PosLookupRecord*  plr;
  FT_Bool*              d;


  if ( ACCESS_Frame( 4L ) )
    return error;

  pcr->GlyphCount = GET_UShort();
  pcr->PosCount   = GET_UShort();

  FORGET_Frame();

  if ( pcr->GlyphCount > cpf2->MaxContextLength )
    cpf2->MaxContextLength = pcr->GlyphCount;

  pcr->Class = NULL;

  count = pcr->GlyphCount - 1;        /* only GlyphCount - 1 elements */

  if ( ALLOC_ARRAY( pcr->Class, count, FT_UShort ) )
    return error;

  c = pcr->Class;
  d = cpf2->ClassDef.Defined;

  if ( ACCESS_Frame( count * 2L ) )
    goto Fail2;

  for ( n = 0; n < count; n++ )
  {
    c[n] = GET_UShort();

    /* We check whether the specific class is used at all.  If not,
       class 0 is used instead.                                     */

    if ( !d[c[n]] )
      c[n] = 0;
  }

  FORGET_Frame();

  pcr->PosLookupRecord = NULL;

  count = pcr->PosCount;

  if ( ALLOC_ARRAY( pcr->PosLookupRecord, count, HB_PosLookupRecord ) )
    goto Fail2;

  plr = pcr->PosLookupRecord;

  if ( ACCESS_Frame( count * 4L ) )
    goto Fail1;

  for ( n = 0; n < count; n++ )
  {
    plr[n].SequenceIndex   = GET_UShort();
    plr[n].LookupListIndex = GET_UShort();
  }

  FORGET_Frame();

  return HB_Err_Ok;

Fail1:
  FREE( plr );

Fail2:
  FREE( c );
  return error;
}


static void  Free_PosClassRule( HB_PosClassRule*  pcr,
				FT_Memory          memory )
{
  FREE( pcr->PosLookupRecord );
  FREE( pcr->Class );
}


/* PosClassSet */

static HB_Error  Load_PosClassSet( HB_ContextPosFormat2*  cpf2,
				   HB_PosClassSet*        pcs,
				   FT_Stream               stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort          n, m, count;
  FT_ULong           cur_offset, new_offset, base_offset;

  HB_PosClassRule*  pcr;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 2L ) )
    return error;

  count = pcs->PosClassRuleCount = GET_UShort();

  FORGET_Frame();

  pcs->PosClassRule = NULL;

  if ( ALLOC_ARRAY( pcs->PosClassRule, count, HB_PosClassRule ) )
    return error;

  pcr = pcs->PosClassRule;

  for ( n = 0; n < count; n++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    cur_offset = FILE_Pos();
    if ( FILE_Seek( new_offset ) ||
	 ( error = Load_PosClassRule( cpf2, &pcr[n],
				      stream ) ) != HB_Err_Ok )
      goto Fail;
    (void)FILE_Seek( cur_offset );
  }

  return HB_Err_Ok;

Fail:
  for ( m = 0; m < n; m++ )
    Free_PosClassRule( &pcr[m], memory );

  FREE( pcr );
  return error;
}


static void  Free_PosClassSet( HB_PosClassSet*  pcs,
			       FT_Memory         memory )
{
  FT_UShort          n, count;

  HB_PosClassRule*  pcr;


  if ( pcs->PosClassRule )
  {
    count = pcs->PosClassRuleCount;
    pcr   = pcs->PosClassRule;

    for ( n = 0; n < count; n++ )
      Free_PosClassRule( &pcr[n], memory );

    FREE( pcr );
  }
}


/* ContextPosFormat2 */

static HB_Error  Load_ContextPos2( HB_ContextPosFormat2*  cpf2,
				   FT_Stream               stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort         n, m, count;
  FT_ULong          cur_offset, new_offset, base_offset;

  HB_PosClassSet*  pcs;


  base_offset = FILE_Pos() - 2;

  if ( ACCESS_Frame( 2L ) )
    return error;

  new_offset = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_Coverage( &cpf2->Coverage, stream ) ) != HB_Err_Ok )
    return error;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 4L ) )
    goto Fail3;

  new_offset = GET_UShort() + base_offset;

  /* `PosClassSetCount' is the upper limit for class values, thus we
     read it now to make an additional safety check.                 */

  count = cpf2->PosClassSetCount = GET_UShort();

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_ClassDefinition( &cpf2->ClassDef, count,
				       stream ) ) != HB_Err_Ok )
    goto Fail3;
  (void)FILE_Seek( cur_offset );

  cpf2->PosClassSet      = NULL;
  cpf2->MaxContextLength = 0;

  if ( ALLOC_ARRAY( cpf2->PosClassSet, count, HB_PosClassSet ) )
    goto Fail2;

  pcs = cpf2->PosClassSet;

  for ( n = 0; n < count; n++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail1;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    if ( new_offset != base_offset )      /* not a NULL offset */
    {
      cur_offset = FILE_Pos();
      if ( FILE_Seek( new_offset ) ||
	   ( error = Load_PosClassSet( cpf2, &pcs[n],
				       stream ) ) != HB_Err_Ok )
	goto Fail1;
      (void)FILE_Seek( cur_offset );
    }
    else
    {
      /* we create a PosClassSet table with no entries */

      cpf2->PosClassSet[n].PosClassRuleCount = 0;
      cpf2->PosClassSet[n].PosClassRule      = NULL;
    }
  }

  return HB_Err_Ok;

Fail1:
  for ( m = 0; m < n; n++ )
    Free_PosClassSet( &pcs[m], memory );

  FREE( pcs );

Fail2:
  _HB_OPEN_Free_ClassDefinition( &cpf2->ClassDef, memory );

Fail3:
  _HB_OPEN_Free_Coverage( &cpf2->Coverage, memory );
  return error;
}


static void  Free_ContextPos2( HB_ContextPosFormat2*  cpf2,
			    FT_Memory               memory )
{
  FT_UShort         n, count;

  HB_PosClassSet*  pcs;


  if ( cpf2->PosClassSet )
  {
    count = cpf2->PosClassSetCount;
    pcs   = cpf2->PosClassSet;

    for ( n = 0; n < count; n++ )
      Free_PosClassSet( &pcs[n], memory );

    FREE( pcs );
  }

  _HB_OPEN_Free_ClassDefinition( &cpf2->ClassDef, memory );
  _HB_OPEN_Free_Coverage( &cpf2->Coverage, memory );
}


/* ContextPosFormat3 */

static HB_Error  Load_ContextPos3( HB_ContextPosFormat3*  cpf3,
				   FT_Stream               stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort             n, count;
  FT_ULong              cur_offset, new_offset, base_offset;

  HB_Coverage*         c;
  HB_PosLookupRecord*  plr;


  base_offset = FILE_Pos() - 2L;

  if ( ACCESS_Frame( 4L ) )
    return error;

  cpf3->GlyphCount = GET_UShort();
  cpf3->PosCount   = GET_UShort();

  FORGET_Frame();

  cpf3->Coverage = NULL;

  count = cpf3->GlyphCount;

  if ( ALLOC_ARRAY( cpf3->Coverage, count, HB_Coverage ) )
    return error;

  c = cpf3->Coverage;

  for ( n = 0; n < count; n++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail2;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    cur_offset = FILE_Pos();
    if ( FILE_Seek( new_offset ) ||
	 ( error = _HB_OPEN_Load_Coverage( &c[n], stream ) ) != HB_Err_Ok )
      goto Fail2;
    (void)FILE_Seek( cur_offset );
  }

  cpf3->PosLookupRecord = NULL;

  count = cpf3->PosCount;

  if ( ALLOC_ARRAY( cpf3->PosLookupRecord, count, HB_PosLookupRecord ) )
    goto Fail2;

  plr = cpf3->PosLookupRecord;

  if ( ACCESS_Frame( count * 4L ) )
    goto Fail1;

  for ( n = 0; n < count; n++ )
  {
    plr[n].SequenceIndex   = GET_UShort();
    plr[n].LookupListIndex = GET_UShort();
  }

  FORGET_Frame();

  return HB_Err_Ok;

Fail1:
  FREE( plr );

Fail2:
  for ( n = 0; n < count; n++ )
    _HB_OPEN_Free_Coverage( &c[n], memory );

  FREE( c );
  return error;
}


static void  Free_ContextPos3( HB_ContextPosFormat3*  cpf3,
			    FT_Memory               memory )
{
  FT_UShort      n, count;

  HB_Coverage*  c;


  FREE( cpf3->PosLookupRecord );

  if ( cpf3->Coverage )
  {
    count = cpf3->GlyphCount;
    c     = cpf3->Coverage;

    for ( n = 0; n < count; n++ )
      _HB_OPEN_Free_Coverage( &c[n], memory );

    FREE( c );
  }
}


/* ContextPos */

static HB_Error  Load_ContextPos( HB_GPOS_SubTable* st,
				  FT_Stream        stream )
{
  HB_Error  error;
  HB_ContextPos*   cp = &st->context;


  if ( ACCESS_Frame( 2L ) )
    return error;

  cp->PosFormat = GET_UShort();

  FORGET_Frame();

  switch ( cp->PosFormat )
  {
  case 1:
    return Load_ContextPos1( &cp->cpf.cpf1, stream );

  case 2:
    return Load_ContextPos2( &cp->cpf.cpf2, stream );

  case 3:
    return Load_ContextPos3( &cp->cpf.cpf3, stream );

  default:
    return _hb_err(HB_Err_Invalid_GPOS_SubTable_Format);
  }

  return HB_Err_Ok;               /* never reached */
}


static void  Free_ContextPos( HB_GPOS_SubTable* st,
			      FT_Memory        memory )
{
  HB_ContextPos*   cp = &st->context;

  switch ( cp->PosFormat )
  {
  case 1:  Free_ContextPos1( &cp->cpf.cpf1, memory ); break;
  case 2:  Free_ContextPos2( &cp->cpf.cpf2, memory ); break;
  case 3:  Free_ContextPos3( &cp->cpf.cpf3, memory ); break;
  default:					      break;
  }
}


static HB_Error  Lookup_ContextPos1( GPOS_Instance*          gpi,
				     HB_ContextPosFormat1*  cpf1,
				     HB_Buffer              buffer,
				     FT_UShort               flags,
				     FT_UShort               context_length,
				     int                     nesting_level )
{
  FT_UShort        index, property;
  FT_UShort        i, j, k, numpr;
  HB_Error         error;
  HB_GPOSHeader*  gpos = gpi->gpos;

  HB_PosRule*     pr;
  HB_GDEFHeader*  gdef;


  gdef = gpos->gdef;

  if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) )
    return error;

  error = _HB_OPEN_Coverage_Index( &cpf1->Coverage, IN_CURGLYPH(), &index );
  if ( error )
    return error;

  pr    = cpf1->PosRuleSet[index].PosRule;
  numpr = cpf1->PosRuleSet[index].PosRuleCount;

  for ( k = 0; k < numpr; k++ )
  {
    if ( context_length != 0xFFFF && context_length < pr[k].GlyphCount )
      goto next_posrule;

    if ( buffer->in_pos + pr[k].GlyphCount > buffer->in_length )
      goto next_posrule;                       /* context is too long */

    for ( i = 1, j = buffer->in_pos + 1; i < pr[k].GlyphCount; i++, j++ )
    {
      while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) )
      {
	if ( error && error != HB_Err_Not_Covered )
	  return error;

	if ( j + pr[k].GlyphCount - i == (FT_Long)buffer->in_length )
	  goto next_posrule;
	j++;
      }

      if ( IN_GLYPH( j ) != pr[k].Input[i - 1] )
	goto next_posrule;
    }

    return Do_ContextPos( gpi, pr[k].GlyphCount,
			  pr[k].PosCount, pr[k].PosLookupRecord,
			  buffer,
			  nesting_level );

    next_posrule:
      ;
  }

  return HB_Err_Not_Covered;
}


static HB_Error  Lookup_ContextPos2( GPOS_Instance*          gpi,
				     HB_ContextPosFormat2*  cpf2,
				     HB_Buffer              buffer,
				     FT_UShort               flags,
				     FT_UShort               context_length,
				     int                     nesting_level )
{
  FT_UShort          index, property;
  HB_Error           error;
  FT_Memory          memory = gpi->face->memory;
  FT_UShort          i, j, k, known_classes;

  FT_UShort*         classes;
  FT_UShort*         cl;
  HB_GPOSHeader*    gpos = gpi->gpos;

  HB_PosClassSet*   pcs;
  HB_PosClassRule*  pr;
  HB_GDEFHeader*    gdef;


  gdef = gpos->gdef;

  if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) )
    return error;

  /* Note: The coverage table in format 2 doesn't give an index into
	   anything.  It just lets us know whether or not we need to
	   do any lookup at all.                                     */

  error = _HB_OPEN_Coverage_Index( &cpf2->Coverage, IN_CURGLYPH(), &index );
  if ( error )
    return error;

  if ( ALLOC_ARRAY( classes, cpf2->MaxContextLength, FT_UShort ) )
    return error;

  error = _HB_OPEN_Get_Class( &cpf2->ClassDef, IN_CURGLYPH(),
		     &classes[0], NULL );
  if ( error && error != HB_Err_Not_Covered )
    goto End;
  known_classes = 0;

  pcs = &cpf2->PosClassSet[classes[0]];
  if ( !pcs )
  {
    error = _hb_err(HB_Err_Invalid_GPOS_SubTable);
    goto End;
  }

  for ( k = 0; k < pcs->PosClassRuleCount; k++ )
  {
    pr = &pcs->PosClassRule[k];

    if ( context_length != 0xFFFF && context_length < pr->GlyphCount )
      goto next_posclassrule;

    if ( buffer->in_pos + pr->GlyphCount > buffer->in_length )
      goto next_posclassrule;                /* context is too long */

    cl   = pr->Class;

    /* Start at 1 because [0] is implied */

    for ( i = 1, j = buffer->in_pos + 1; i < pr->GlyphCount; i++, j++ )
    {
      while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) )
      {
	if ( error && error != HB_Err_Not_Covered )
	  goto End;

	if ( j + pr->GlyphCount - i == (FT_Long)buffer->in_length )
	  goto next_posclassrule;
	j++;
      }

      if ( i > known_classes )
      {
	/* Keeps us from having to do this for each rule */

	error = _HB_OPEN_Get_Class( &cpf2->ClassDef, IN_GLYPH( j ), &classes[i], NULL );
	if ( error && error != HB_Err_Not_Covered )
	  goto End;
	known_classes = i;
      }

      if ( cl[i - 1] != classes[i] )
	goto next_posclassrule;
    }

    error = Do_ContextPos( gpi, pr->GlyphCount,
			   pr->PosCount, pr->PosLookupRecord,
			   buffer,
			   nesting_level );
    goto End;

  next_posclassrule:
    ;
  }

  error = HB_Err_Not_Covered;

End:
  FREE( classes );
  return error;
}


static HB_Error  Lookup_ContextPos3( GPOS_Instance*          gpi,
				     HB_ContextPosFormat3*  cpf3,
				     HB_Buffer              buffer,
				     FT_UShort               flags,
				     FT_UShort               context_length,
				     int                     nesting_level )
{
  HB_Error         error;
  FT_UShort        index, i, j, property;
  HB_GPOSHeader*  gpos = gpi->gpos;

  HB_Coverage*    c;
  HB_GDEFHeader*  gdef;


  gdef = gpos->gdef;

  if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) )
    return error;

  if ( context_length != 0xFFFF && context_length < cpf3->GlyphCount )
    return HB_Err_Not_Covered;

  if ( buffer->in_pos + cpf3->GlyphCount > buffer->in_length )
    return HB_Err_Not_Covered;         /* context is too long */

  c    = cpf3->Coverage;

  for ( i = 1, j = 1; i < cpf3->GlyphCount; i++, j++ )
  {
    while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) )
    {
      if ( error && error != HB_Err_Not_Covered )
	return error;

      if ( j + cpf3->GlyphCount - i == (FT_Long)buffer->in_length )
	return HB_Err_Not_Covered;
      j++;
    }

    error = _HB_OPEN_Coverage_Index( &c[i], IN_GLYPH( j ), &index );
    if ( error )
      return error;
  }

  return Do_ContextPos( gpi, cpf3->GlyphCount,
			cpf3->PosCount, cpf3->PosLookupRecord,
			buffer,
			nesting_level );
}


static HB_Error  Lookup_ContextPos( GPOS_Instance*    gpi,
				    HB_GPOS_SubTable* st,
				    HB_Buffer        buffer,
				    FT_UShort         flags,
				    FT_UShort         context_length,
				    int               nesting_level )
{
  HB_ContextPos*   cp = &st->context;

  switch ( cp->PosFormat )
  {
  case 1:
    return Lookup_ContextPos1( gpi, &cp->cpf.cpf1, buffer,
			       flags, context_length, nesting_level );

  case 2:
    return Lookup_ContextPos2( gpi, &cp->cpf.cpf2, buffer,
			       flags, context_length, nesting_level );

  case 3:
    return Lookup_ContextPos3( gpi, &cp->cpf.cpf3, buffer,
			       flags, context_length, nesting_level );

  default:
    return _hb_err(HB_Err_Invalid_GPOS_SubTable_Format);
  }

  return HB_Err_Ok;               /* never reached */
}


/* LookupType 8 */

/* ChainPosRule */

static HB_Error  Load_ChainPosRule( HB_ChainPosRule*  cpr,
				    FT_Stream          stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort             n, count;
  FT_UShort*            b;
  FT_UShort*            i;
  FT_UShort*            l;

  HB_PosLookupRecord*  plr;


  if ( ACCESS_Frame( 2L ) )
    return error;

  cpr->BacktrackGlyphCount = GET_UShort();

  FORGET_Frame();

  cpr->Backtrack = NULL;

  count = cpr->BacktrackGlyphCount;

  if ( ALLOC_ARRAY( cpr->Backtrack, count, FT_UShort ) )
    return error;

  b = cpr->Backtrack;

  if ( ACCESS_Frame( count * 2L ) )
    goto Fail4;

  for ( n = 0; n < count; n++ )
    b[n] = GET_UShort();

  FORGET_Frame();

  if ( ACCESS_Frame( 2L ) )
    goto Fail4;

  cpr->InputGlyphCount = GET_UShort();

  FORGET_Frame();

  cpr->Input = NULL;

  count = cpr->InputGlyphCount - 1;  /* only InputGlyphCount - 1 elements */

  if ( ALLOC_ARRAY( cpr->Input, count, FT_UShort ) )
    goto Fail4;

  i = cpr->Input;

  if ( ACCESS_Frame( count * 2L ) )
    goto Fail3;

  for ( n = 0; n < count; n++ )
    i[n] = GET_UShort();

  FORGET_Frame();

  if ( ACCESS_Frame( 2L ) )
    goto Fail3;

  cpr->LookaheadGlyphCount = GET_UShort();

  FORGET_Frame();

  cpr->Lookahead = NULL;

  count = cpr->LookaheadGlyphCount;

  if ( ALLOC_ARRAY( cpr->Lookahead, count, FT_UShort ) )
    goto Fail3;

  l = cpr->Lookahead;

  if ( ACCESS_Frame( count * 2L ) )
    goto Fail2;

  for ( n = 0; n < count; n++ )
    l[n] = GET_UShort();

  FORGET_Frame();

  if ( ACCESS_Frame( 2L ) )
    goto Fail2;

  cpr->PosCount = GET_UShort();

  FORGET_Frame();

  cpr->PosLookupRecord = NULL;

  count = cpr->PosCount;

  if ( ALLOC_ARRAY( cpr->PosLookupRecord, count, HB_PosLookupRecord ) )
    goto Fail2;

  plr = cpr->PosLookupRecord;

  if ( ACCESS_Frame( count * 4L ) )
    goto Fail1;

  for ( n = 0; n < count; n++ )
  {
    plr[n].SequenceIndex   = GET_UShort();
    plr[n].LookupListIndex = GET_UShort();
  }

  FORGET_Frame();

  return HB_Err_Ok;

Fail1:
  FREE( plr );

Fail2:
  FREE( l );

Fail3:
  FREE( i );

Fail4:
  FREE( b );
  return error;
}


static void  Free_ChainPosRule( HB_ChainPosRule*  cpr,
				FT_Memory          memory )
{
  FREE( cpr->PosLookupRecord );
  FREE( cpr->Lookahead );
  FREE( cpr->Input );
  FREE( cpr->Backtrack );
}


/* ChainPosRuleSet */

static HB_Error  Load_ChainPosRuleSet( HB_ChainPosRuleSet*  cprs,
				       FT_Stream             stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort          n, m, count;
  FT_ULong           cur_offset, new_offset, base_offset;

  HB_ChainPosRule*  cpr;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 2L ) )
    return error;

  count = cprs->ChainPosRuleCount = GET_UShort();

  FORGET_Frame();

  cprs->ChainPosRule = NULL;

  if ( ALLOC_ARRAY( cprs->ChainPosRule, count, HB_ChainPosRule ) )
    return error;

  cpr = cprs->ChainPosRule;

  for ( n = 0; n < count; n++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    cur_offset = FILE_Pos();
    if ( FILE_Seek( new_offset ) ||
	 ( error = Load_ChainPosRule( &cpr[n], stream ) ) != HB_Err_Ok )
      goto Fail;
    (void)FILE_Seek( cur_offset );
  }

  return HB_Err_Ok;

Fail:
  for ( m = 0; m < n; m++ )
    Free_ChainPosRule( &cpr[m], memory );

  FREE( cpr );
  return error;
}


static void  Free_ChainPosRuleSet( HB_ChainPosRuleSet*  cprs,
				   FT_Memory             memory )
{
  FT_UShort          n, count;

  HB_ChainPosRule*  cpr;


  if ( cprs->ChainPosRule )
  {
    count = cprs->ChainPosRuleCount;
    cpr   = cprs->ChainPosRule;

    for ( n = 0; n < count; n++ )
      Free_ChainPosRule( &cpr[n], memory );

    FREE( cpr );
  }
}


/* ChainContextPosFormat1 */

static HB_Error  Load_ChainContextPos1( HB_ChainContextPosFormat1*  ccpf1,
					FT_Stream                    stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort             n, m, count;
  FT_ULong              cur_offset, new_offset, base_offset;

  HB_ChainPosRuleSet*  cprs;


  base_offset = FILE_Pos() - 2L;

  if ( ACCESS_Frame( 2L ) )
    return error;

  new_offset = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_Coverage( &ccpf1->Coverage, stream ) ) != HB_Err_Ok )
    return error;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 2L ) )
    goto Fail2;

  count = ccpf1->ChainPosRuleSetCount = GET_UShort();

  FORGET_Frame();

  ccpf1->ChainPosRuleSet = NULL;

  if ( ALLOC_ARRAY( ccpf1->ChainPosRuleSet, count, HB_ChainPosRuleSet ) )
    goto Fail2;

  cprs = ccpf1->ChainPosRuleSet;

  for ( n = 0; n < count; n++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail1;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    cur_offset = FILE_Pos();
    if ( FILE_Seek( new_offset ) ||
	 ( error = Load_ChainPosRuleSet( &cprs[n], stream ) ) != HB_Err_Ok )
      goto Fail1;
    (void)FILE_Seek( cur_offset );
  }

  return HB_Err_Ok;

Fail1:
  for ( m = 0; m < n; m++ )
    Free_ChainPosRuleSet( &cprs[m], memory );

  FREE( cprs );

Fail2:
  _HB_OPEN_Free_Coverage( &ccpf1->Coverage, memory );
  return error;
}


static void  Free_ChainContextPos1( HB_ChainContextPosFormat1*  ccpf1,
				 FT_Memory                    memory )
{
  FT_UShort             n, count;

  HB_ChainPosRuleSet*  cprs;


  if ( ccpf1->ChainPosRuleSet )
  {
    count = ccpf1->ChainPosRuleSetCount;
    cprs  = ccpf1->ChainPosRuleSet;

    for ( n = 0; n < count; n++ )
      Free_ChainPosRuleSet( &cprs[n], memory );

    FREE( cprs );
  }

  _HB_OPEN_Free_Coverage( &ccpf1->Coverage, memory );
}


/* ChainPosClassRule */

static HB_Error  Load_ChainPosClassRule(
		   HB_ChainContextPosFormat2*  ccpf2,
		   HB_ChainPosClassRule*       cpcr,
		   FT_Stream                    stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort             n, count;

  FT_UShort*            b;
  FT_UShort*            i;
  FT_UShort*            l;
  HB_PosLookupRecord*  plr;
  FT_Bool*              d;


  if ( ACCESS_Frame( 2L ) )
    return error;

  cpcr->BacktrackGlyphCount = GET_UShort();

  FORGET_Frame();

  if ( cpcr->BacktrackGlyphCount > ccpf2->MaxBacktrackLength )
    ccpf2->MaxBacktrackLength = cpcr->BacktrackGlyphCount;

  cpcr->Backtrack = NULL;

  count = cpcr->BacktrackGlyphCount;

  if ( ALLOC_ARRAY( cpcr->Backtrack, count, FT_UShort ) )
    return error;

  b = cpcr->Backtrack;
  d = ccpf2->BacktrackClassDef.Defined;

  if ( ACCESS_Frame( count * 2L ) )
    goto Fail4;

  for ( n = 0; n < count; n++ )
  {
    b[n] = GET_UShort();

    /* We check whether the specific class is used at all.  If not,
       class 0 is used instead.                                     */

    if ( !d[b[n]] )
      b[n] = 0;
  }

  FORGET_Frame();

  if ( ACCESS_Frame( 2L ) )
    goto Fail4;

  cpcr->InputGlyphCount = GET_UShort();

  if ( cpcr->InputGlyphCount > ccpf2->MaxInputLength )
    ccpf2->MaxInputLength = cpcr->InputGlyphCount;

  FORGET_Frame();

  cpcr->Input = NULL;

  count = cpcr->InputGlyphCount - 1; /* only InputGlyphCount - 1 elements */

  if ( ALLOC_ARRAY( cpcr->Input, count, FT_UShort ) )
    goto Fail4;

  i = cpcr->Input;
  d = ccpf2->InputClassDef.Defined;

  if ( ACCESS_Frame( count * 2L ) )
    goto Fail3;

  for ( n = 0; n < count; n++ )
  {
    i[n] = GET_UShort();

    if ( !d[i[n]] )
      i[n] = 0;
  }

  FORGET_Frame();

  if ( ACCESS_Frame( 2L ) )
    goto Fail3;

  cpcr->LookaheadGlyphCount = GET_UShort();

  FORGET_Frame();

  if ( cpcr->LookaheadGlyphCount > ccpf2->MaxLookaheadLength )
    ccpf2->MaxLookaheadLength = cpcr->LookaheadGlyphCount;

  cpcr->Lookahead = NULL;

  count = cpcr->LookaheadGlyphCount;

  if ( ALLOC_ARRAY( cpcr->Lookahead, count, FT_UShort ) )
    goto Fail3;

  l = cpcr->Lookahead;
  d = ccpf2->LookaheadClassDef.Defined;

  if ( ACCESS_Frame( count * 2L ) )
    goto Fail2;

  for ( n = 0; n < count; n++ )
  {
    l[n] = GET_UShort();

    if ( !d[l[n]] )
      l[n] = 0;
  }

  FORGET_Frame();

  if ( ACCESS_Frame( 2L ) )
    goto Fail2;

  cpcr->PosCount = GET_UShort();

  FORGET_Frame();

  cpcr->PosLookupRecord = NULL;

  count = cpcr->PosCount;

  if ( ALLOC_ARRAY( cpcr->PosLookupRecord, count, HB_PosLookupRecord ) )
    goto Fail2;

  plr = cpcr->PosLookupRecord;

  if ( ACCESS_Frame( count * 4L ) )
    goto Fail1;

  for ( n = 0; n < count; n++ )
  {
    plr[n].SequenceIndex   = GET_UShort();
    plr[n].LookupListIndex = GET_UShort();
  }

  FORGET_Frame();

  return HB_Err_Ok;

Fail1:
  FREE( plr );

Fail2:
  FREE( l );

Fail3:
  FREE( i );

Fail4:
  FREE( b );
  return error;
}


static void  Free_ChainPosClassRule( HB_ChainPosClassRule*  cpcr,
				     FT_Memory               memory )
{
  FREE( cpcr->PosLookupRecord );
  FREE( cpcr->Lookahead );
  FREE( cpcr->Input );
  FREE( cpcr->Backtrack );
}


/* PosClassSet */

static HB_Error  Load_ChainPosClassSet(
		   HB_ChainContextPosFormat2*  ccpf2,
		   HB_ChainPosClassSet*        cpcs,
		   FT_Stream                    stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort               n, m, count;
  FT_ULong                cur_offset, new_offset, base_offset;

  HB_ChainPosClassRule*  cpcr;


  base_offset = FILE_Pos();

  if ( ACCESS_Frame( 2L ) )
    return error;

  count = cpcs->ChainPosClassRuleCount = GET_UShort();

  FORGET_Frame();

  cpcs->ChainPosClassRule = NULL;

  if ( ALLOC_ARRAY( cpcs->ChainPosClassRule, count,
		    HB_ChainPosClassRule ) )
    return error;

  cpcr = cpcs->ChainPosClassRule;

  for ( n = 0; n < count; n++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    cur_offset = FILE_Pos();
    if ( FILE_Seek( new_offset ) ||
	 ( error = Load_ChainPosClassRule( ccpf2, &cpcr[n],
					   stream ) ) != HB_Err_Ok )
      goto Fail;
    (void)FILE_Seek( cur_offset );
  }

  return HB_Err_Ok;

Fail:
  for ( m = 0; m < n; m++ )
    Free_ChainPosClassRule( &cpcr[m], memory );

  FREE( cpcr );
  return error;
}


static void  Free_ChainPosClassSet( HB_ChainPosClassSet*  cpcs,
				    FT_Memory              memory )
{
  FT_UShort               n, count;

  HB_ChainPosClassRule*  cpcr;


  if ( cpcs->ChainPosClassRule )
  {
    count = cpcs->ChainPosClassRuleCount;
    cpcr  = cpcs->ChainPosClassRule;

    for ( n = 0; n < count; n++ )
      Free_ChainPosClassRule( &cpcr[n], memory );

    FREE( cpcr );
  }
}


static HB_Error GPOS_Load_EmptyOrClassDefinition( HB_ClassDefinition*  cd,
					     FT_UShort             limit,
					     FT_ULong              class_offset,
					     FT_ULong              base_offset,
					     FT_Stream             stream )
{
  HB_Error error;
  FT_ULong               cur_offset;

  cur_offset = FILE_Pos();

  if ( class_offset )
    {
      if ( !FILE_Seek( class_offset + base_offset ) )
	error = _HB_OPEN_Load_ClassDefinition( cd, limit, stream );
    }
  else
     error = _HB_OPEN_Load_EmptyClassDefinition ( cd, stream );

  if (error == HB_Err_Ok)
    (void)FILE_Seek( cur_offset ); /* Changes error as a side-effect */

  return error;
}

/* ChainContextPosFormat2 */

static HB_Error  Load_ChainContextPos2( HB_ChainContextPosFormat2*  ccpf2,
					FT_Stream                    stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort              n, m, count;
  FT_ULong               cur_offset, new_offset, base_offset;
  FT_ULong               backtrack_offset, input_offset, lookahead_offset;

  HB_ChainPosClassSet*  cpcs;


  base_offset = FILE_Pos() - 2;

  if ( ACCESS_Frame( 2L ) )
    return error;

  new_offset = GET_UShort() + base_offset;

  FORGET_Frame();

  cur_offset = FILE_Pos();
  if ( FILE_Seek( new_offset ) ||
       ( error = _HB_OPEN_Load_Coverage( &ccpf2->Coverage, stream ) ) != HB_Err_Ok )
    return error;
  (void)FILE_Seek( cur_offset );

  if ( ACCESS_Frame( 8L ) )
    goto Fail5;

  backtrack_offset = GET_UShort();
  input_offset     = GET_UShort();
  lookahead_offset = GET_UShort();

  /* `ChainPosClassSetCount' is the upper limit for input class values,
     thus we read it now to make an additional safety check. No limit
     is known or needed for the other two class definitions          */

  count = ccpf2->ChainPosClassSetCount = GET_UShort();

  FORGET_Frame();

  if ( ( error = GPOS_Load_EmptyOrClassDefinition( &ccpf2->BacktrackClassDef, 65535,
					      backtrack_offset, base_offset,
					      stream ) ) != HB_Err_Ok )
    goto Fail5;
  if ( ( error = GPOS_Load_EmptyOrClassDefinition( &ccpf2->InputClassDef, count,
					      input_offset, base_offset,
					      stream ) ) != HB_Err_Ok )
    goto Fail4;
  if ( ( error = GPOS_Load_EmptyOrClassDefinition( &ccpf2->LookaheadClassDef, 65535,
					      lookahead_offset, base_offset,
					      stream ) ) != HB_Err_Ok )
    goto Fail3;

  ccpf2->ChainPosClassSet   = NULL;
  ccpf2->MaxBacktrackLength = 0;
  ccpf2->MaxInputLength     = 0;
  ccpf2->MaxLookaheadLength = 0;

  if ( ALLOC_ARRAY( ccpf2->ChainPosClassSet, count, HB_ChainPosClassSet ) )
    goto Fail2;

  cpcs = ccpf2->ChainPosClassSet;

  for ( n = 0; n < count; n++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail1;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    if ( new_offset != base_offset )      /* not a NULL offset */
    {
      cur_offset = FILE_Pos();
      if ( FILE_Seek( new_offset ) ||
	   ( error = Load_ChainPosClassSet( ccpf2, &cpcs[n],
					    stream ) ) != HB_Err_Ok )
	goto Fail1;
      (void)FILE_Seek( cur_offset );
    }
    else
    {
      /* we create a ChainPosClassSet table with no entries */

      ccpf2->ChainPosClassSet[n].ChainPosClassRuleCount = 0;
      ccpf2->ChainPosClassSet[n].ChainPosClassRule      = NULL;
    }
  }

  return HB_Err_Ok;

Fail1:
  for ( m = 0; m < n; m++ )
    Free_ChainPosClassSet( &cpcs[m], memory );

  FREE( cpcs );

Fail2:
  _HB_OPEN_Free_ClassDefinition( &ccpf2->LookaheadClassDef, memory );

Fail3:
  _HB_OPEN_Free_ClassDefinition( &ccpf2->InputClassDef, memory );

Fail4:
  _HB_OPEN_Free_ClassDefinition( &ccpf2->BacktrackClassDef, memory );

Fail5:
  _HB_OPEN_Free_Coverage( &ccpf2->Coverage, memory );
  return error;
}


static void  Free_ChainContextPos2( HB_ChainContextPosFormat2*  ccpf2,
				 FT_Memory                    memory )
{
  FT_UShort              n, count;

  HB_ChainPosClassSet*  cpcs;


  if ( ccpf2->ChainPosClassSet )
  {
    count = ccpf2->ChainPosClassSetCount;
    cpcs  = ccpf2->ChainPosClassSet;

    for ( n = 0; n < count; n++ )
      Free_ChainPosClassSet( &cpcs[n], memory );

    FREE( cpcs );
  }

  _HB_OPEN_Free_ClassDefinition( &ccpf2->LookaheadClassDef, memory );
  _HB_OPEN_Free_ClassDefinition( &ccpf2->InputClassDef, memory );
  _HB_OPEN_Free_ClassDefinition( &ccpf2->BacktrackClassDef, memory );

  _HB_OPEN_Free_Coverage( &ccpf2->Coverage, memory );
}


/* ChainContextPosFormat3 */

static HB_Error  Load_ChainContextPos3( HB_ChainContextPosFormat3*  ccpf3,
					FT_Stream                    stream )
{
  HB_Error  error;
  FT_Memory memory = stream->memory;

  FT_UShort             n, nb, ni, nl, m, count;
  FT_UShort             backtrack_count, input_count, lookahead_count;
  FT_ULong              cur_offset, new_offset, base_offset;

  HB_Coverage*         b;
  HB_Coverage*         i;
  HB_Coverage*         l;
  HB_PosLookupRecord*  plr;


  base_offset = FILE_Pos() - 2L;

  if ( ACCESS_Frame( 2L ) )
    return error;

  ccpf3->BacktrackGlyphCount = GET_UShort();

  FORGET_Frame();

  ccpf3->BacktrackCoverage = NULL;

  backtrack_count = ccpf3->BacktrackGlyphCount;

  if ( ALLOC_ARRAY( ccpf3->BacktrackCoverage, backtrack_count,
		    HB_Coverage ) )
    return error;

  b = ccpf3->BacktrackCoverage;

  for ( nb = 0; nb < backtrack_count; nb++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail4;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    cur_offset = FILE_Pos();
    if ( FILE_Seek( new_offset ) ||
	 ( error = _HB_OPEN_Load_Coverage( &b[nb], stream ) ) != HB_Err_Ok )
      goto Fail4;
    (void)FILE_Seek( cur_offset );
  }

  if ( ACCESS_Frame( 2L ) )
    goto Fail4;

  ccpf3->InputGlyphCount = GET_UShort();

  FORGET_Frame();

  ccpf3->InputCoverage = NULL;

  input_count = ccpf3->InputGlyphCount;

  if ( ALLOC_ARRAY( ccpf3->InputCoverage, input_count, HB_Coverage ) )
    goto Fail4;

  i = ccpf3->InputCoverage;

  for ( ni = 0; ni < input_count; ni++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail3;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    cur_offset = FILE_Pos();
    if ( FILE_Seek( new_offset ) ||
	 ( error = _HB_OPEN_Load_Coverage( &i[ni], stream ) ) != HB_Err_Ok )
      goto Fail3;
    (void)FILE_Seek( cur_offset );
  }

  if ( ACCESS_Frame( 2L ) )
    goto Fail3;

  ccpf3->LookaheadGlyphCount = GET_UShort();

  FORGET_Frame();

  ccpf3->LookaheadCoverage = NULL;

  lookahead_count = ccpf3->LookaheadGlyphCount;

  if ( ALLOC_ARRAY( ccpf3->LookaheadCoverage, lookahead_count,
		    HB_Coverage ) )
    goto Fail3;

  l = ccpf3->LookaheadCoverage;

  for ( nl = 0; nl < lookahead_count; nl++ )
  {
    if ( ACCESS_Frame( 2L ) )
      goto Fail2;

    new_offset = GET_UShort() + base_offset;

    FORGET_Frame();

    cur_offset = FILE_Pos();
    if ( FILE_Seek( new_offset ) ||
	 ( error = _HB_OPEN_Load_Coverage( &l[nl], stream ) ) != HB_Err_Ok )
      goto Fail2;
    (void)FILE_Seek( cur_offset );
  }

  if ( ACCESS_Frame( 2L ) )
    goto Fail2;

  ccpf3->PosCount = GET_UShort();

  FORGET_Frame();

  ccpf3->PosLookupRecord = NULL;

  count = ccpf3->PosCount;

  if ( ALLOC_ARRAY( ccpf3->PosLookupRecord, count, HB_PosLookupRecord ) )
    goto Fail2;

  plr = ccpf3->PosLookupRecord;

  if ( ACCESS_Frame( count * 4L ) )
    goto Fail1;

  for ( n = 0; n < count; n++ )
  {
    plr[n].SequenceIndex   = GET_UShort();
    plr[n].LookupListIndex = GET_UShort();
  }

  FORGET_Frame();

  return HB_Err_Ok;

Fail1:
  FREE( plr );

Fail2:
  for ( m = 0; m < nl; m++ )
    _HB_OPEN_Free_Coverage( &l[m], memory );

  FREE( l );

Fail3:
  for ( m = 0; m < ni; m++ )
    _HB_OPEN_Free_Coverage( &i[m], memory );

  FREE( i );

Fail4:
  for ( m = 0; m < nb; m++ )
    _HB_OPEN_Free_Coverage( &b[m], memory );

  FREE( b );
  return error;
}


static void  Free_ChainContextPos3( HB_ChainContextPosFormat3*  ccpf3,
				 FT_Memory                    memory )
{
  FT_UShort      n, count;

  HB_Coverage*  c;


  FREE( ccpf3->PosLookupRecord );

  if ( ccpf3->LookaheadCoverage )
  {
    count = ccpf3->LookaheadGlyphCount;
    c     = ccpf3->LookaheadCoverage;

    for ( n = 0; n < count; n++ )
      _HB_OPEN_Free_Coverage( &c[n], memory );

    FREE( c );
  }

  if ( ccpf3->InputCoverage )
  {
    count = ccpf3->InputGlyphCount;
    c     = ccpf3->InputCoverage;

    for ( n = 0; n < count; n++ )
      _HB_OPEN_Free_Coverage( &c[n], memory );

    FREE( c );
  }

  if ( ccpf3->BacktrackCoverage )
  {
    count = ccpf3->BacktrackGlyphCount;
    c     = ccpf3->BacktrackCoverage;

    for ( n = 0; n < count; n++ )
      _HB_OPEN_Free_Coverage( &c[n], memory );

    FREE( c );
  }
}


/* ChainContextPos */

static HB_Error  Load_ChainContextPos( HB_GPOS_SubTable* st,
				       FT_Stream             stream )
{
  HB_Error  error;
  HB_ChainContextPos*  ccp = &st->chain;


  if ( ACCESS_Frame( 2L ) )
    return error;

  ccp->PosFormat = GET_UShort();

  FORGET_Frame();

  switch ( ccp->PosFormat )
  {
  case 1:
    return Load_ChainContextPos1( &ccp->ccpf.ccpf1, stream );

  case 2:
    return Load_ChainContextPos2( &ccp->ccpf.ccpf2, stream );

  case 3:
    return Load_ChainContextPos3( &ccp->ccpf.ccpf3, stream );

  default:
    return _hb_err(HB_Err_Invalid_GPOS_SubTable_Format);
  }

  return HB_Err_Ok;               /* never reached */
}


static void  Free_ChainContextPos( HB_GPOS_SubTable* st,
				   FT_Memory             memory )
{
  HB_ChainContextPos*  ccp = &st->chain;

  switch ( ccp->PosFormat )
  {
  case 1:  Free_ChainContextPos1( &ccp->ccpf.ccpf1, memory ); break;
  case 2:  Free_ChainContextPos2( &ccp->ccpf.ccpf2, memory ); break;
  case 3:  Free_ChainContextPos3( &ccp->ccpf.ccpf3, memory ); break;
  default:						      break;
  }
}


static HB_Error  Lookup_ChainContextPos1(
		   GPOS_Instance*               gpi,
		   HB_ChainContextPosFormat1*  ccpf1,
		   HB_Buffer                   buffer,
		   FT_UShort                    flags,
		   FT_UShort                    context_length,
		   int                          nesting_level )
{
  FT_UShort          index, property;
  FT_UShort          i, j, k, num_cpr;
  FT_UShort          bgc, igc, lgc;
  HB_Error           error;
  HB_GPOSHeader*    gpos = gpi->gpos;

  HB_ChainPosRule*  cpr;
  HB_ChainPosRule   curr_cpr;
  HB_GDEFHeader*    gdef;


  gdef = gpos->gdef;

  if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) )
    return error;

  error = _HB_OPEN_Coverage_Index( &ccpf1->Coverage, IN_CURGLYPH(), &index );
  if ( error )
    return error;

  cpr     = ccpf1->ChainPosRuleSet[index].ChainPosRule;
  num_cpr = ccpf1->ChainPosRuleSet[index].ChainPosRuleCount;

  for ( k = 0; k < num_cpr; k++ )
  {
    curr_cpr = cpr[k];
    bgc      = curr_cpr.BacktrackGlyphCount;
    igc      = curr_cpr.InputGlyphCount;
    lgc      = curr_cpr.LookaheadGlyphCount;

    if ( context_length != 0xFFFF && context_length < igc )
      goto next_chainposrule;

    /* check whether context is too long; it is a first guess only */

    if ( bgc > buffer->in_pos || buffer->in_pos + igc + lgc > buffer->in_length )
      goto next_chainposrule;

    if ( bgc )
    {
      /* Since we don't know in advance the number of glyphs to inspect,
	 we search backwards for matches in the backtrack glyph array    */

      for ( i = 0, j = buffer->in_pos - 1; i < bgc; i++, j-- )
      {
	while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) )
	{
	  if ( error && error != HB_Err_Not_Covered )
	    return error;

	  if ( j + 1 == bgc - i )
	    goto next_chainposrule;
	  j--;
	}

	/* In OpenType 1.3, it is undefined whether the offsets of
	   backtrack glyphs is in logical order or not.  Version 1.4
	   will clarify this:

	     Logical order -      a  b  c  d  e  f  g  h  i  j
					      i
	     Input offsets -                  0  1
	     Backtrack offsets -  3  2  1  0
	     Lookahead offsets -                    0  1  2  3           */

	if ( IN_GLYPH( j ) != curr_cpr.Backtrack[i] )
	  goto next_chainposrule;
      }
    }

    /* Start at 1 because [0] is implied */

    for ( i = 1, j = buffer->in_pos + 1; i < igc; i++, j++ )
    {
      while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) )
      {
	if ( error && error != HB_Err_Not_Covered )
	  return error;

	if ( j + igc - i + lgc == (FT_Long)buffer->in_length )
	  goto next_chainposrule;
	j++;
      }

      if ( IN_GLYPH( j ) != curr_cpr.Input[i - 1] )
	goto next_chainposrule;
    }

    /* we are starting to check for lookahead glyphs right after the
       last context glyph                                            */

    for ( i = 0; i < lgc; i++, j++ )
    {
      while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) )
      {
	if ( error && error != HB_Err_Not_Covered )
	  return error;

	if ( j + lgc - i == (FT_Long)buffer->in_length )
	  goto next_chainposrule;
	j++;
      }

      if ( IN_GLYPH( j ) != curr_cpr.Lookahead[i] )
	goto next_chainposrule;
    }

    return Do_ContextPos( gpi, igc,
			  curr_cpr.PosCount,
			  curr_cpr.PosLookupRecord,
			  buffer,
			  nesting_level );

  next_chainposrule:
    ;
  }

  return HB_Err_Not_Covered;
}


static HB_Error  Lookup_ChainContextPos2(
		   GPOS_Instance*               gpi,
		   HB_ChainContextPosFormat2*  ccpf2,
		   HB_Buffer                   buffer,
		   FT_UShort                    flags,
		   FT_UShort                    context_length,
		   int                          nesting_level )
{
  FT_UShort              index, property;
  FT_Memory              memory = gpi->face->memory;
  HB_Error               error;
  FT_UShort              i, j, k;
  FT_UShort              bgc, igc, lgc;
  FT_UShort              known_backtrack_classes,
			 known_input_classes,
			 known_lookahead_classes;

  FT_UShort*             backtrack_classes;
  FT_UShort*             input_classes;
  FT_UShort*             lookahead_classes;

  FT_UShort*             bc;
  FT_UShort*             ic;
  FT_UShort*             lc;
  HB_GPOSHeader*        gpos = gpi->gpos;

  HB_ChainPosClassSet*  cpcs;
  HB_ChainPosClassRule  cpcr;
  HB_GDEFHeader*        gdef;


  gdef = gpos->gdef;

  if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) )
    return error;

  /* Note: The coverage table in format 2 doesn't give an index into
	   anything.  It just lets us know whether or not we need to
	   do any lookup at all.                                     */

  error = _HB_OPEN_Coverage_Index( &ccpf2->Coverage, IN_CURGLYPH(), &index );
  if ( error )
    return error;

  if ( ALLOC_ARRAY( backtrack_classes, ccpf2->MaxBacktrackLength, FT_UShort ) )
    return error;
  known_backtrack_classes = 0;

  if ( ALLOC_ARRAY( input_classes, ccpf2->MaxInputLength, FT_UShort ) )
    goto End3;
  known_input_classes = 1;

  if ( ALLOC_ARRAY( lookahead_classes, ccpf2->MaxLookaheadLength, FT_UShort ) )
    goto End2;
  known_lookahead_classes = 0;

  error = _HB_OPEN_Get_Class( &ccpf2->InputClassDef, IN_CURGLYPH(),
		     &input_classes[0], NULL );
  if ( error && error != HB_Err_Not_Covered )
    goto End1;

  cpcs = &ccpf2->ChainPosClassSet[input_classes[0]];
  if ( !cpcs )
  {
    error = _hb_err(HB_Err_Invalid_GPOS_SubTable);
    goto End1;
  }

  for ( k = 0; k < cpcs->ChainPosClassRuleCount; k++ )
  {
    cpcr = cpcs->ChainPosClassRule[k];
    bgc  = cpcr.BacktrackGlyphCount;
    igc  = cpcr.InputGlyphCount;
    lgc  = cpcr.LookaheadGlyphCount;

    if ( context_length != 0xFFFF && context_length < igc )
      goto next_chainposclassrule;

    /* check whether context is too long; it is a first guess only */

    if ( bgc > buffer->in_pos || buffer->in_pos + igc + lgc > buffer->in_length )
      goto next_chainposclassrule;

    if ( bgc )
    {
      /* Since we don't know in advance the number of glyphs to inspect,
	 we search backwards for matches in the backtrack glyph array.
	 Note that `known_backtrack_classes' starts at index 0.         */

      bc       = cpcr.Backtrack;

      for ( i = 0, j = buffer->in_pos - 1; i < bgc; i++, j-- )
      {
	while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) )
	{
	  if ( error && error != HB_Err_Not_Covered )
	    goto End1;

	  if ( j + 1 == bgc - i )
	    goto next_chainposclassrule;
	  j++;
	}

	if ( i >= known_backtrack_classes )
	{
	  /* Keeps us from having to do this for each rule */

	  error = _HB_OPEN_Get_Class( &ccpf2->BacktrackClassDef, IN_GLYPH( j ),
			     &backtrack_classes[i], NULL );
	  if ( error && error != HB_Err_Not_Covered )
	    goto End1;
	  known_backtrack_classes = i;
	}

	if ( bc[i] != backtrack_classes[i] )
	  goto next_chainposclassrule;
      }
    }

    ic       = cpcr.Input;

    /* Start at 1 because [0] is implied */

    for ( i = 1, j = buffer->in_pos + 1; i < igc; i++, j++ )
    {
      while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) )
      {
	if ( error && error != HB_Err_Not_Covered )
	  goto End1;

	if ( j + igc - i + lgc == (FT_Long)buffer->in_length )
	  goto next_chainposclassrule;
	j++;
      }

      if ( i >= known_input_classes )
      {
	error = _HB_OPEN_Get_Class( &ccpf2->InputClassDef, IN_GLYPH( j ),
			   &input_classes[i], NULL );
	if ( error && error != HB_Err_Not_Covered )
	  goto End1;
	known_input_classes = i;
      }

      if ( ic[i - 1] != input_classes[i] )
	goto next_chainposclassrule;
    }

    /* we are starting to check for lookahead glyphs right after the
       last context glyph                                            */

    lc       = cpcr.Lookahead;

    for ( i = 0; i < lgc; i++, j++ )
    {
      while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) )
      {
	if ( error && error != HB_Err_Not_Covered )
	  goto End1;

	if ( j + lgc - i == (FT_Long)buffer->in_length )
	  goto next_chainposclassrule;
	j++;
      }

      if ( i >= known_lookahead_classes )
      {
	error = _HB_OPEN_Get_Class( &ccpf2->LookaheadClassDef, IN_GLYPH( j ),
			   &lookahead_classes[i], NULL );
	if ( error && error != HB_Err_Not_Covered )
	  goto End1;
	known_lookahead_classes = i;
      }

      if ( lc[i] != lookahead_classes[i] )
	goto next_chainposclassrule;
    }

    error = Do_ContextPos( gpi, igc,
			   cpcr.PosCount,
			   cpcr.PosLookupRecord,
			   buffer,
			   nesting_level );
    goto End1;

  next_chainposclassrule:
    ;
  }

  error = HB_Err_Not_Covered;

End1:
  FREE( lookahead_classes );

End2:
  FREE( input_classes );

End3:
  FREE( backtrack_classes );
  return error;
}


static HB_Error  Lookup_ChainContextPos3(
		   GPOS_Instance*               gpi,
		   HB_ChainContextPosFormat3*  ccpf3,
		   HB_Buffer                   buffer,
		   FT_UShort                    flags,
		   FT_UShort                    context_length,
		   int                          nesting_level )
{
  FT_UShort        index, i, j, property;
  FT_UShort        bgc, igc, lgc;
  HB_Error         error;
  HB_GPOSHeader*  gpos = gpi->gpos;

  HB_Coverage*    bc;
  HB_Coverage*    ic;
  HB_Coverage*    lc;
  HB_GDEFHeader*  gdef;


  gdef = gpos->gdef;

  if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) )
    return error;

  bgc = ccpf3->BacktrackGlyphCount;
  igc = ccpf3->InputGlyphCount;
  lgc = ccpf3->LookaheadGlyphCount;

  if ( context_length != 0xFFFF && context_length < igc )
    return HB_Err_Not_Covered;

  /* check whether context is too long; it is a first guess only */

  if ( bgc > buffer->in_pos || buffer->in_pos + igc + lgc > buffer->in_length )
    return HB_Err_Not_Covered;

  if ( bgc )
  {
    /* Since we don't know in advance the number of glyphs to inspect,
       we search backwards for matches in the backtrack glyph array    */

    bc       = ccpf3->BacktrackCoverage;

    for ( i = 0, j = buffer->in_pos - 1; i < bgc; i++, j-- )
    {
      while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) )
      {
	if ( error && error != HB_Err_Not_Covered )
	  return error;

	if ( j + 1 == bgc - i )
	  return HB_Err_Not_Covered;
	j--;
      }

      error = _HB_OPEN_Coverage_Index( &bc[i], IN_GLYPH( j ), &index );
      if ( error )
	return error;
    }
  }

  ic       = ccpf3->InputCoverage;

  for ( i = 0, j = buffer->in_pos; i < igc; i++, j++ )
  {
    /* We already called CHECK_Property for IN_GLYPH ( buffer->in_pos ) */
    while ( j > buffer->in_pos && CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) )
    {
      if ( error && error != HB_Err_Not_Covered )
	return error;

      if ( j + igc - i + lgc == (FT_Long)buffer->in_length )
	return HB_Err_Not_Covered;
      j++;
    }

    error = _HB_OPEN_Coverage_Index( &ic[i], IN_GLYPH( j ), &index );
    if ( error )
      return error;
  }

  /* we are starting to check for lookahead glyphs right after the
     last context glyph                                            */

  lc       = ccpf3->LookaheadCoverage;

  for ( i = 0; i < lgc; i++, j++ )
  {
    while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) )
    {
      if ( error && error != HB_Err_Not_Covered )
	return error;

      if ( j + lgc - i == (FT_Long)buffer->in_length )
	return HB_Err_Not_Covered;
      j++;
    }

    error = _HB_OPEN_Coverage_Index( &lc[i], IN_GLYPH( j ), &index );
    if ( error )
      return error;
  }

  return Do_ContextPos( gpi, igc,
			ccpf3->PosCount,
			ccpf3->PosLookupRecord,
			buffer,
			nesting_level );
}


static HB_Error  Lookup_ChainContextPos(
		   GPOS_Instance*        gpi,
		   HB_GPOS_SubTable* st,
		   HB_Buffer            buffer,
		   FT_UShort             flags,
		   FT_UShort             context_length,
		   int                   nesting_level )
{
  HB_ChainContextPos*  ccp = &st->chain;

  switch ( ccp->PosFormat )
  {
  case 1:
    return Lookup_ChainContextPos1( gpi, &ccp->ccpf.ccpf1, buffer,
				    flags, context_length,
				    nesting_level );

  case 2:
    return Lookup_ChainContextPos2( gpi, &ccp->ccpf.ccpf2, buffer,
				    flags, context_length,
				    nesting_level );

  case 3:
    return Lookup_ChainContextPos3( gpi, &ccp->ccpf.ccpf3, buffer,
				    flags, context_length,
				    nesting_level );

  default:
    return _hb_err(HB_Err_Invalid_GPOS_SubTable_Format);
  }

  return HB_Err_Ok;               /* never reached */
}



/***********
 * GPOS API
 ***********/



HB_Error  HB_GPOS_Select_Script( HB_GPOSHeader*  gpos,
				 FT_ULong         script_tag,
				 FT_UShort*       script_index )
{
  FT_UShort          n;

  HB_ScriptList*    sl;
  HB_ScriptRecord*  sr;


  if ( !gpos || !script_index )
    return HB_Err_Invalid_Argument;

  sl = &gpos->ScriptList;
  sr = sl->ScriptRecord;

  for ( n = 0; n < sl->ScriptCount; n++ )
    if ( script_tag == sr[n].ScriptTag )
    {
      *script_index = n;

      return HB_Err_Ok;
    }

  return HB_Err_Not_Covered;
}



HB_Error  HB_GPOS_Select_Language( HB_GPOSHeader*  gpos,
				   FT_ULong         language_tag,
				   FT_UShort        script_index,
				   FT_UShort*       language_index,
				   FT_UShort*       req_feature_index )
{
  FT_UShort           n;

  HB_ScriptList*     sl;
  HB_ScriptRecord*   sr;
  HB_Script*         s;
  HB_LangSysRecord*  lsr;


  if ( !gpos || !language_index || !req_feature_index )
    return HB_Err_Invalid_Argument;

  sl = &gpos->ScriptList;
  sr = sl->ScriptRecord;

  if ( script_index >= sl->ScriptCount )
    return HB_Err_Invalid_Argument;

  s   = &sr[script_index].Script;
  lsr = s->LangSysRecord;

  for ( n = 0; n < s->LangSysCount; n++ )
    if ( language_tag == lsr[n].LangSysTag )
    {
      *language_index = n;
      *req_feature_index = lsr[n].LangSys.ReqFeatureIndex;

      return HB_Err_Ok;
    }

  return HB_Err_Not_Covered;
}


/* selecting 0xFFFF for language_index asks for the values of the
   default language (DefaultLangSys)                              */


HB_Error  HB_GPOS_Select_Feature( HB_GPOSHeader*  gpos,
				  FT_ULong         feature_tag,
				  FT_UShort        script_index,
				  FT_UShort        language_index,
				  FT_UShort*       feature_index )
{
  FT_UShort           n;

  HB_ScriptList*     sl;
  HB_ScriptRecord*   sr;
  HB_Script*         s;
  HB_LangSysRecord*  lsr;
  HB_LangSys*        ls;
  FT_UShort*          fi;

  HB_FeatureList*    fl;
  HB_FeatureRecord*  fr;


  if ( !gpos || !feature_index )
    return HB_Err_Invalid_Argument;

  sl = &gpos->ScriptList;
  sr = sl->ScriptRecord;

  fl = &gpos->FeatureList;
  fr = fl->FeatureRecord;

  if ( script_index >= sl->ScriptCount )
    return HB_Err_Invalid_Argument;

  s   = &sr[script_index].Script;
  lsr = s->LangSysRecord;

  if ( language_index == 0xFFFF )
    ls = &s->DefaultLangSys;
  else
  {
    if ( language_index >= s->LangSysCount )
      return HB_Err_Invalid_Argument;

    ls = &lsr[language_index].LangSys;
  }

  fi = ls->FeatureIndex;

  for ( n = 0; n < ls->FeatureCount; n++ )
  {
    if ( fi[n] >= fl->FeatureCount )
      return _hb_err(HB_Err_Invalid_GPOS_SubTable_Format);

    if ( feature_tag == fr[fi[n]].FeatureTag )
    {
      *feature_index = fi[n];

      return HB_Err_Ok;
    }
  }

  return HB_Err_Not_Covered;
}


/* The next three functions return a null-terminated list */


HB_Error  HB_GPOS_Query_Scripts( HB_GPOSHeader*  gpos,
				 FT_ULong**       script_tag_list )
{
  HB_Error           error;
  FT_Memory          memory;
  FT_UShort          n;
  FT_ULong*          stl;

  HB_ScriptList*    sl;
  HB_ScriptRecord*  sr;


  if ( !gpos || !script_tag_list )
    return HB_Err_Invalid_Argument;

  memory = gpos->memory;
  sl = &gpos->ScriptList;
  sr = sl->ScriptRecord;

  if ( ALLOC_ARRAY( stl, sl->ScriptCount + 1, FT_ULong ) )
    return error;

  for ( n = 0; n < sl->ScriptCount; n++ )
    stl[n] = sr[n].ScriptTag;
  stl[n] = 0;

  *script_tag_list = stl;

  return HB_Err_Ok;
}



HB_Error  HB_GPOS_Query_Languages( HB_GPOSHeader*  gpos,
				   FT_UShort        script_index,
				   FT_ULong**       language_tag_list )
{
  HB_Error            error;
  FT_Memory           memory;
  FT_UShort           n;
  FT_ULong*           ltl;

  HB_ScriptList*     sl;
  HB_ScriptRecord*   sr;
  HB_Script*         s;
  HB_LangSysRecord*  lsr;


  if ( !gpos || !language_tag_list )
    return HB_Err_Invalid_Argument;

  memory = gpos->memory;
  sl = &gpos->ScriptList;
  sr = sl->ScriptRecord;

  if ( script_index >= sl->ScriptCount )
    return HB_Err_Invalid_Argument;

  s   = &sr[script_index].Script;
  lsr = s->LangSysRecord;

  if ( ALLOC_ARRAY( ltl, s->LangSysCount + 1, FT_ULong ) )
    return error;

  for ( n = 0; n < s->LangSysCount; n++ )
    ltl[n] = lsr[n].LangSysTag;
  ltl[n] = 0;

  *language_tag_list = ltl;

  return HB_Err_Ok;
}


/* selecting 0xFFFF for language_index asks for the values of the
   default language (DefaultLangSys)                              */


HB_Error  HB_GPOS_Query_Features( HB_GPOSHeader*  gpos,
				  FT_UShort        script_index,
				  FT_UShort        language_index,
				  FT_ULong**       feature_tag_list )
{
  FT_UShort           n;
  HB_Error            error;
  FT_Memory           memory;
  FT_ULong*           ftl;

  HB_ScriptList*     sl;
  HB_ScriptRecord*   sr;
  HB_Script*         s;
  HB_LangSysRecord*  lsr;
  HB_LangSys*        ls;
  FT_UShort*          fi;

  HB_FeatureList*    fl;
  HB_FeatureRecord*  fr;


  if ( !gpos || !feature_tag_list )
    return HB_Err_Invalid_Argument;

  memory = gpos->memory;
  sl = &gpos->ScriptList;
  sr = sl->ScriptRecord;

  fl = &gpos->FeatureList;
  fr = fl->FeatureRecord;

  if ( script_index >= sl->ScriptCount )
    return HB_Err_Invalid_Argument;

  s   = &sr[script_index].Script;
  lsr = s->LangSysRecord;

  if ( language_index == 0xFFFF )
    ls = &s->DefaultLangSys;
  else
  {
    if ( language_index >= s->LangSysCount )
      return HB_Err_Invalid_Argument;

    ls = &lsr[language_index].LangSys;
  }

  fi = ls->FeatureIndex;

  if ( ALLOC_ARRAY( ftl, ls->FeatureCount + 1, FT_ULong ) )
    return error;

  for ( n = 0; n < ls->FeatureCount; n++ )
  {
    if ( fi[n] >= fl->FeatureCount )
    {
      FREE( ftl );
      return _hb_err(HB_Err_Invalid_GPOS_SubTable_Format);
    }
    ftl[n] = fr[fi[n]].FeatureTag;
  }
  ftl[n] = 0;

  *feature_tag_list = ftl;

  return HB_Err_Ok;
}


/* Do an individual subtable lookup.  Returns HB_Err_Ok if positioning
   has been done, or HB_Err_Not_Covered if not.                        */
static HB_Error  GPOS_Do_Glyph_Lookup( GPOS_Instance*    gpi,
				       FT_UShort         lookup_index,
				       HB_Buffer        buffer,
				       FT_UShort         context_length,
				       int               nesting_level )
{
  HB_Error             error = HB_Err_Not_Covered;
  FT_UShort            i, flags, lookup_count;
  HB_GPOSHeader*       gpos = gpi->gpos;
  HB_Lookup*           lo;
  int		       lookup_type;


  nesting_level++;

  if ( nesting_level > HB_MAX_NESTING_LEVEL )
    return _hb_err(HB_Err_Too_Many_Nested_Contexts);

  lookup_count = gpos->LookupList.LookupCount;
  if (lookup_index >= lookup_count)
    return error;

  lo    = &gpos->LookupList.Lookup[lookup_index];
  flags = lo->LookupFlag;
  lookup_type = lo->LookupType;

  for ( i = 0; i < lo->SubTableCount; i++ )
  {
    HB_GPOS_SubTable *st = &lo->SubTable[i].st.gpos;

    switch (lookup_type) {
      case HB_GPOS_LOOKUP_SINGLE:
        error = Lookup_SinglePos	( gpi, st, buffer, flags, context_length, nesting_level ); break;
      case HB_GPOS_LOOKUP_PAIR:
	error = Lookup_PairPos		( gpi, st, buffer, flags, context_length, nesting_level ); break;
      case HB_GPOS_LOOKUP_CURSIVE:
	error = Lookup_CursivePos	( gpi, st, buffer, flags, context_length, nesting_level ); break;
      case HB_GPOS_LOOKUP_MARKBASE:
	error = Lookup_MarkBasePos	( gpi, st, buffer, flags, context_length, nesting_level ); break;
      case HB_GPOS_LOOKUP_MARKLIG:
	error = Lookup_MarkLigPos	( gpi, st, buffer, flags, context_length, nesting_level ); break;
      case HB_GPOS_LOOKUP_MARKMARK:
	error = Lookup_MarkMarkPos	( gpi, st, buffer, flags, context_length, nesting_level ); break;
      case HB_GPOS_LOOKUP_CONTEXT:
	error = Lookup_ContextPos	( gpi, st, buffer, flags, context_length, nesting_level ); break;
      case HB_GPOS_LOOKUP_CHAIN:
	error = Lookup_ChainContextPos	( gpi, st, buffer, flags, context_length, nesting_level ); break;
    /*case HB_GPOS_LOOKUP_EXTENSION:
	error = Lookup_ExtensionPos	( gpi, st, buffer, flags, context_length, nesting_level ); break;*/
      default:
	error = HB_Err_Not_Covered;
    }

    /* Check whether we have a successful positioning or an error other
       than HB_Err_Not_Covered                                         */
    if ( error != HB_Err_Not_Covered )
      return error;
  }

  return HB_Err_Not_Covered;
}


HB_Error  _HB_GPOS_Load_SubTable( HB_GPOS_SubTable*  st,
				  FT_Stream     stream,
				  FT_UShort     lookup_type )
{
  switch ( lookup_type ) {
    case HB_GPOS_LOOKUP_SINGLE:		return Load_SinglePos		( st, stream );
    case HB_GPOS_LOOKUP_PAIR:		return Load_PairPos		( st, stream );
    case HB_GPOS_LOOKUP_CURSIVE:	return Load_CursivePos		( st, stream );
    case HB_GPOS_LOOKUP_MARKBASE:	return Load_MarkBasePos		( st, stream );
    case HB_GPOS_LOOKUP_MARKLIG:	return Load_MarkLigPos		( st, stream );
    case HB_GPOS_LOOKUP_MARKMARK:	return Load_MarkMarkPos		( st, stream );
    case HB_GPOS_LOOKUP_CONTEXT:	return Load_ContextPos		( st, stream );
    case HB_GPOS_LOOKUP_CHAIN:		return Load_ChainContextPos	( st, stream );
  /*case HB_GPOS_LOOKUP_EXTENSION:	return Load_ExtensionPos	( st, stream );*/
    default:				return _hb_err(HB_Err_Invalid_GPOS_SubTable_Format);
  }
}


void  _HB_GPOS_Free_SubTable( HB_GPOS_SubTable*  st,
			      FT_Memory     memory,
			      FT_UShort     lookup_type )
{
  switch ( lookup_type ) {
    case HB_GPOS_LOOKUP_SINGLE:		Free_SinglePos		( st, memory ); return;
    case HB_GPOS_LOOKUP_PAIR:		Free_PairPos		( st, memory ); return;
    case HB_GPOS_LOOKUP_CURSIVE:	Free_CursivePos		( st, memory ); return;
    case HB_GPOS_LOOKUP_MARKBASE:	Free_MarkBasePos	( st, memory ); return;
    case HB_GPOS_LOOKUP_MARKLIG:	Free_MarkLigPos		( st, memory ); return;
    case HB_GPOS_LOOKUP_MARKMARK:	Free_MarkMarkPos	( st, memory ); return;
    case HB_GPOS_LOOKUP_CONTEXT:	Free_ContextPos		( st, memory ); return;
    case HB_GPOS_LOOKUP_CHAIN:		Free_ChainContextPos	( st, memory ); return;
  /*case HB_GPOS_LOOKUP_EXTENSION:	Free_ExtensionPos	( st, memory ); return;*/
    default:									return;
  }
}


/* apply one lookup to the input string object */

static HB_Error  GPOS_Do_String_Lookup( GPOS_Instance*    gpi,
				   FT_UShort         lookup_index,
				   HB_Buffer        buffer )
{
  HB_Error         error, retError = HB_Err_Not_Covered;
  HB_GPOSHeader*  gpos = gpi->gpos;

  FT_UInt*  properties = gpos->LookupList.Properties;

  const int       nesting_level = 0;
  /* 0xFFFF indicates that we don't have a context length yet */
  const FT_UShort context_length = 0xFFFF;


  gpi->last  = 0xFFFF;     /* no last valid glyph for cursive pos. */

  buffer->in_pos = 0;
  while ( buffer->in_pos < buffer->in_length )
  {
    if ( ~IN_PROPERTIES( buffer->in_pos ) & properties[lookup_index] )
    {
      /* Note that the connection between mark and base glyphs hold
	 exactly one (string) lookup.  For example, it would be possible
	 that in the first lookup, mark glyph X is attached to base
	 glyph A, and in the next lookup it is attached to base glyph B.
	 It is up to the font designer to provide meaningful lookups and
	 lookup order.                                                   */

      error = GPOS_Do_Glyph_Lookup( gpi, lookup_index, buffer, context_length, nesting_level );
      if ( error && error != HB_Err_Not_Covered )
	return error;
    }
    else
    {
      /* Contrary to properties defined in GDEF, user-defined properties
	 will always stop a possible cursive positioning.                */
      gpi->last = 0xFFFF;

      error = HB_Err_Not_Covered;
    }

    if ( error == HB_Err_Not_Covered )
      (buffer->in_pos)++;
    else
      retError = error;
  }

  return retError;
}


static HB_Error  Position_CursiveChain ( HB_Buffer     buffer )
{
  FT_ULong   i, j;
  HB_Position positions = buffer->positions;

  /* First handle all left-to-right connections */
  for (j = 0; j < buffer->in_length; j--)
  {
    if (positions[j].cursive_chain > 0)
      positions[j].y_pos += positions[j - positions[j].cursive_chain].y_pos;
  }

  /* Then handle all right-to-left connections */
  for (i = buffer->in_length; i > 0; i--)
  {
    j = i - 1;

    if (positions[j].cursive_chain < 0)
      positions[j].y_pos += positions[j - positions[j].cursive_chain].y_pos;
  }

  return HB_Err_Ok;
}


HB_Error  HB_GPOS_Add_Feature( HB_GPOSHeader*  gpos,
			       FT_UShort        feature_index,
			       FT_UInt          property )
{
  FT_UShort    i;

  HB_Feature  feature;
  FT_UInt*     properties;
  FT_UShort*   index;
  FT_UShort    lookup_count;

  /* Each feature can only be added once */

  if ( !gpos ||
       feature_index >= gpos->FeatureList.FeatureCount ||
       gpos->FeatureList.ApplyCount == gpos->FeatureList.FeatureCount )
    return HB_Err_Invalid_Argument;

  gpos->FeatureList.ApplyOrder[gpos->FeatureList.ApplyCount++] = feature_index;

  properties = gpos->LookupList.Properties;

  feature = gpos->FeatureList.FeatureRecord[feature_index].Feature;
  index   = feature.LookupListIndex;
  lookup_count = gpos->LookupList.LookupCount;

  for ( i = 0; i < feature.LookupListCount; i++ )
  {
    FT_UShort lookup_index = index[i];
    if (lookup_index < lookup_count)
      properties[lookup_index] |= property;
  }

  return HB_Err_Ok;
}



HB_Error  HB_GPOS_Clear_Features( HB_GPOSHeader*  gpos )
{
  FT_UShort i;

  FT_UInt*  properties;


  if ( !gpos )
    return HB_Err_Invalid_Argument;

  gpos->FeatureList.ApplyCount = 0;

  properties = gpos->LookupList.Properties;

  for ( i = 0; i < gpos->LookupList.LookupCount; i++ )
    properties[i] = 0;

  return HB_Err_Ok;
}



HB_Error  HB_GPOS_Register_Glyph_Function( HB_GPOSHeader*    gpos,
					   HB_GlyphFunction  gfunc )
{
  if ( !gpos )
    return HB_Err_Invalid_Argument;

  gpos->gfunc = gfunc;

  return HB_Err_Ok;
}



HB_Error  HB_GPOS_Register_MM_Function( HB_GPOSHeader*  gpos,
					HB_MMFunction   mmfunc,
					void*            data )
{
  if ( !gpos )
    return HB_Err_Invalid_Argument;

  gpos->mmfunc = mmfunc;
  gpos->data   = data;

  return HB_Err_Ok;
}

/* If `dvi' is TRUE, glyph contour points for anchor points and device
   tables are ignored -- you will get device independent values.         */


HB_Error  HB_GPOS_Apply_String( FT_Face           face,
				HB_GPOSHeader*    gpos,
				FT_UShort         load_flags,
				HB_Buffer         buffer,
				FT_Bool           dvi,
				FT_Bool           r2l )
{
  HB_Error       error, retError = HB_Err_Not_Covered;
  GPOS_Instance  gpi;
  FT_UShort      i, j, lookup_count;

  if ( !face || !gpos || !buffer )
    return HB_Err_Invalid_Argument;

  if ( buffer->in_length == 0 )
    return HB_Err_Not_Covered;

  gpi.face       = face;
  gpi.gpos       = gpos;
  gpi.load_flags = load_flags;
  gpi.r2l        = r2l;
  gpi.dvi        = dvi;

  lookup_count = gpos->LookupList.LookupCount;

  for ( i = 0; i < gpos->FeatureList.ApplyCount; i++ )
  {
    FT_UShort  feature_index = gpos->FeatureList.ApplyOrder[i];
    HB_Feature feature = gpos->FeatureList.FeatureRecord[feature_index].Feature;

    for ( j = 0; j < feature.LookupListCount; j++ )
    {
      FT_UShort lookup_index = feature.LookupListIndex[j];

      /* Skip nonexistant lookups */
      if (lookup_index >= lookup_count)
       continue;

      error = GPOS_Do_String_Lookup( &gpi, lookup_index, buffer );
      if ( error )
      {
	if ( error != HB_Err_Not_Covered )
	  return error;
      }
      else
	retError = error;
    }
  }

  error = Position_CursiveChain ( buffer );
  if ( error )
    return error;

  return retError;
}

/* END */