+ case _IONBF:
+ /* When unbuffered I/O is requested, we keep the buffer anyway, as
+ we don't want to e.g. flush the stream for every character of a
+ stream being printed.
+ */
+ break;
+ case _IOFBF:
+ case _IOLBF:
+ if ( size > INT_MAX || size == NULL )
+ {
+ /* PDCLib only supports buffers up to INT_MAX in size. A size
+ of zero doesn't make sense.
+ */
+ return -1;
+ }
+ if ( buf == NULL )
+ {
+ /* User requested buffer size, but leaves it to library to
+ allocate the buffer.
+ */
+ if ( ( stream->bufsize < size ) || ( stream->bufsize > ( size << 1 ) ) )
+ {
+ /* If current buffer is big enough for requested size, but
+ not over twice as big (and wasting memory space), we use
+ the current buffer (i.e., do nothing), to save the
+ malloc() / free() overhead.
+ */
+ /* Free the buffer allocated by fopen(), and allocate a new
+ one.
+ */
+ if ( ( buf = (char *) malloc( size ) ) == NULL )
+ {
+ /* Out of memory error. */
+ return -1;
+ }
+ }
+ }
+ else
+ {
+ /* User provided buffer -> set flag to not free() the buffer
+ on fclose().
+ */
+ stream->status &= ~ _PDCLIB_LIBBUFFER;
+ }
+ free( stream->buffer );
+ stream->buffer = buf;
+ stream->bufsize = size;
+ break;
+ default:
+ /* If mode is something else than _IOFBF, _IOLBF or _IONBF -> exit */
+ return -1;