FT_Stream_GetUOffset( FT_Stream stream )
{
FT_Byte* p;
FT_Long result;
FT_ASSERT( stream && stream->cursor );
result = 0;
p = stream->cursor;
if ( p + 2 < stream->limit )
result = FT_NEXT_UOFF3( p );
stream->cursor = p;
return result;
}
FT_Stream_ReadUOffset( FT_Stream stream,
FT_Error* error )
{
FT_Byte reads[3];
FT_Byte* p = 0;
FT_Long result = 0;
FT_ASSERT( stream );
*error = FT_Err_Ok;
if ( stream->pos + 2 < stream->size )
{
if ( stream->read )
{
if (stream->read( stream, stream->pos, reads, 3L ) != 3L )
goto Fail;
p = reads;
}
else
{
p = stream->base + stream->pos;
}
if ( p )
result = FT_NEXT_UOFF3( p );
}
else
goto Fail;
stream->pos += 3;
return result;
Fail:
*error = FT_Err_Invalid_Stream_Operation;
FT_ERROR(( "FT_Stream_ReadUOffset:"
" invalid i/o; pos = 0x%lx, size = 0x%lx\n",
stream->pos, stream->size ));
return 0;
}
FT_Stream_ReadFields( FT_Stream stream,
const FT_Frame_Field* fields,
void* structure )
{
FT_Error error;
FT_Bool frame_accessed = 0;
FT_Byte* cursor = stream->cursor;
if ( !fields || !stream )
return FT_Err_Invalid_Argument;
error = FT_Err_Ok;
do
{
FT_ULong value;
FT_Int sign_shift;
FT_Byte* p;
switch ( fields->value )
{
case ft_frame_start: /* access a new frame */
error = FT_Stream_EnterFrame( stream, fields->offset );
if ( error )
goto Exit;
frame_accessed = 1;
cursor = stream->cursor;
fields++;
continue; /* loop! */
case ft_frame_bytes: /* read a byte sequence */
case ft_frame_skip: /* skip some bytes */
{
FT_UInt len = fields->size;
if ( cursor + len > stream->limit )
{
error = FT_Err_Invalid_Stream_Operation;
goto Exit;
}
if ( fields->value == ft_frame_bytes )
{
p = (FT_Byte*)structure + fields->offset;
FT_MEM_COPY( p, cursor, len );
}
cursor += len;
fields++;
continue;
}
case ft_frame_byte:
case ft_frame_schar: /* read a single byte */
value = FT_NEXT_BYTE(cursor);
sign_shift = 24;
break;
case ft_frame_short_be:
case ft_frame_ushort_be: /* read a 2-byte big-endian short */
value = FT_NEXT_USHORT(cursor);
sign_shift = 16;
break;
case ft_frame_short_le:
case ft_frame_ushort_le: /* read a 2-byte little-endian short */
value = FT_NEXT_USHORT_LE(cursor);
sign_shift = 16;
break;
case ft_frame_long_be:
case ft_frame_ulong_be: /* read a 4-byte big-endian long */
value = FT_NEXT_ULONG(cursor);
sign_shift = 0;
break;
case ft_frame_long_le:
case ft_frame_ulong_le: /* read a 4-byte little-endian long */
value = FT_NEXT_ULONG_LE(cursor);
sign_shift = 0;
break;
case ft_frame_off3_be:
case ft_frame_uoff3_be: /* read a 3-byte big-endian long */
value = FT_NEXT_UOFF3(cursor);
sign_shift = 8;
break;
case ft_frame_off3_le:
case ft_frame_uoff3_le: /* read a 3-byte little-endian long */
value = FT_NEXT_UOFF3_LE(cursor);
sign_shift = 8;
break;
default:
/* otherwise, exit the loop */
stream->cursor = cursor;
goto Exit;
}
/* now, compute the signed value is necessary */
if ( fields->value & FT_FRAME_OP_SIGNED )
value = (FT_ULong)( (FT_Int32)( value << sign_shift ) >> sign_shift );
/* finally, store the value in the object */
p = (FT_Byte*)structure + fields->offset;
switch ( fields->size )
{
case (8 / FT_CHAR_BIT):
*(FT_Byte*)p = (FT_Byte)value;
break;
case (16 / FT_CHAR_BIT):
*(FT_UShort*)p = (FT_UShort)value;
break;
case (32 / FT_CHAR_BIT):
*(FT_UInt32*)p = (FT_UInt32)value;
break;
default: /* for 64-bit systems */
*(FT_ULong*)p = (FT_ULong)value;
}
/* go to next field */
fields++;
}
while ( 1 );
Exit:
/* close the frame if it was opened by this read */
if ( frame_accessed )
FT_Stream_ExitFrame( stream );
return error;
}
