On Tue, Nov 24, 2020 at 04:21:53PM +0100, Toke Høiland-Jørgensen wrote:
> +/* Helper macros to loop over a series of TLVs.
> + * @start pointer to first TLV
> + * @end byte * pointer to TLV stream end
> + * @tlv struct babel_tlv pointer used as iterator
> + */
> +#define WALK_TLVS(start, end, tlv, saddr, ifname) \
> + for (tlv = (void *)start; \
> + (byte *)tlv < end; \
> + tlv = NEXT_TLV(tlv)) \
> + { \
> + byte *loop_pos; \
> + /* Ugly special case */ \
> + if (tlv->type == BABEL_TLV_PAD1) \
> + continue; \
> + \
> + /* The end of the common TLV header */ \
> + loop_pos = (byte *)tlv + sizeof(struct babel_tlv);
> \
> + if ((loop_pos > end) || (loop_pos + tlv->length > end)) \
...
> static inline int
> babel_read_subtlvs(struct babel_tlv *hdr,
> union babel_msg *msg,
> struct babel_parse_state *state)
> {
> + const struct babel_tlv_data *tlv_data;
> + struct babel_proto *p = state->proto;
> struct babel_tlv *tlv;
> - byte *pos, *end = (byte *) hdr + TLV_LENGTH(hdr);
> + byte *end = (byte *) hdr + TLV_LENGTH(hdr);
> int res;
>
> - for (tlv = (void *) hdr + state->current_tlv_endpos;
> - (byte *) tlv < end;
> - tlv = NEXT_TLV(tlv))
> + WALK_TLVS(hdr + state->current_tlv_endpos, end, tlv,
> + state->saddr, state->ifa->ifname)
> {
Huh? This macro usage depends on typecast of a part if its first argument.
That is completely confusing. One see 'hdr + state->current_tlv_endpos',
but it is a different operation.
Also jumping from such macro to a fixed label is a bit confusing ...
--
Elen sila lumenn' omentielvo
Ondrej 'Santiago' Zajicek (email: [email protected])
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"To err is human -- to blame it on a computer is even more so."
