Kevin Ryde <[EMAIL PROTECTED]> writes:
> I'm looking at this to allow non-zero tail array only when the layout
> provides for it. I think all the internal uses of structs have no
> tail array (and a zero size) so that should all be ok. Dunno if
> anyone else might have used the tail size to get some sneaky extra
> space. Sounds like the wrong thing to do, but could always be
> loosened up again later.
Looks good, except I'm not keen on the "goto bad_tail_size;". It
would be marginally more friendly to have different error messages for
the two cases anyway. (e.g. as below and "tail array not allowed if
struct has a zero length layout")
Regards,
Neil
>
> --- struct.c.~1.111.2.4.~ 2007-02-22 09:37:43.000000000 +1100
> +++ struct.c 2007-02-26 10:40:36.000000000 +1100
> @@ -430,6 +430,27 @@
> layout = SCM_PACK (SCM_STRUCT_DATA (vtable) [scm_vtable_index_layout]);
> basic_size = scm_i_symbol_length (layout) / 2;
> tail_elts = scm_to_size_t (tail_array_size);
> +
> + /* A tail array is only allowed if the layout fields string ends in "R",
> + "W" or "O". */
> + if (tail_elts != 0)
> + {
> + SCM layout_str, last_char;
> + int last_c;
> +
> + if (basic_size == 0)
> + {
> + bad_tail_size:
> + SCM_MISC_ERROR ("tail array not allowed unless layout ends R, W,
> or O", SCM_EOL);
> + }
> +
> + layout_str = scm_symbol_to_string (layout);
> + last_char = scm_string_ref (layout_str,
> + scm_from_size_t (2 * basic_size - 1));
> + if (! SCM_LAYOUT_TAILP (SCM_CHAR (last_char)))
> + goto bad_tail_size;
> + }
> +
> SCM_CRITICAL_SECTION_START;
> if (SCM_STRUCT_DATA (vtable)[scm_struct_i_flags] & SCM_STRUCTF_ENTITY)
> {
_______________________________________________
Guile-devel mailing list
Guile-devel@gnu.org
http://lists.gnu.org/mailman/listinfo/guile-devel
