On Thu, Nov 07, 2024 at 07:43:26PM +0100, Stefano Brivio wrote:cppcheck 2.16.0 reports: dhcpv6.c:334:14: style: The comparison 'ia_type == 3' is always true. [knownConditionTrueFalse] if (ia_type == OPT_IA_NA) { ^ dhcpv6.c:306:12: note: 'ia_type' is assigned value '3' here. ia_type = OPT_IA_NA; ^ dhcpv6.c:334:14: note: The comparison 'ia_type == 3' is always true. if (ia_type == OPT_IA_NA) { ^ this is not really the case as we set ia_type to OPT_IA_TA and then jump back. Anyway, there's no particular reason to use a goto here: add a trivial foreach() macro to go through elements of an array and use it instead. Signed-off-by: Stefano Brivio <sbrivio(a)redhat.com>Reviewed-by: David Gibson <david(a)gibson.dropbear.id.au>--- dhcpv6.c | 47 +++++++++++++++++++++-------------------------- util.h | 3 +++ 2 files changed, 24 insertions(+), 26 deletions(-) diff --git a/dhcpv6.c b/dhcpv6.c index 14a5c7e..f2e7307 100644 --- a/dhcpv6.c +++ b/dhcpv6.c @@ -296,47 +296,42 @@ static struct opt_hdr *dhcpv6_opt(const struct pool *p, size_t *offset, static struct opt_hdr *dhcpv6_ia_notonlink(const struct pool *p, struct in6_addr *la) { + int ia_types[2] = { OPT_IA_NA, OPT_IA_TA }, *ia_type; + const struct opt_ia_addr *opt_addr; char buf[INET6_ADDRSTRLEN]; struct in6_addr req_addr; const struct opt_hdr *h; struct opt_hdr *ia; size_t offset; - int ia_type; - ia_type = OPT_IA_NA; -ia_ta: - offset = 0; - while ((ia = dhcpv6_opt(p, &offset, ia_type))) { - if (ntohs(ia->l) < OPT_VSIZE(ia_na)) - return NULL; + foreach(ia_type, ia_types) { + offset = 0; + while ((ia = dhcpv6_opt(p, &offset, *ia_type))) { + if (ntohs(ia->l) < OPT_VSIZE(ia_na)) + return NULL; - offset += sizeof(struct opt_ia_na); + offset += sizeof(struct opt_ia_na); - while ((h = dhcpv6_opt(p, &offset, OPT_IAAADR))) { - const struct opt_ia_addr *opt_addr; + while ((h = dhcpv6_opt(p, &offset, OPT_IAAADR))) { + if (ntohs(h->l) != OPT_VSIZE(ia_addr)) + return NULL; - if (ntohs(h->l) != OPT_VSIZE(ia_addr)) - return NULL; + opt_addr = (const struct opt_ia_addr *)h; + req_addr = opt_addr->addr; + if (!IN6_ARE_ADDR_EQUAL(la, &req_addr)) + goto err; - opt_addr = (const struct opt_ia_addr *)h; - req_addr = opt_addr->addr; - if (!IN6_ARE_ADDR_EQUAL(la, &req_addr)) { - info("DHCPv6: requested address %s not on link", - inet_ntop(AF_INET6, &req_addr, - buf, sizeof(buf))); - return ia; + offset += sizeof(struct opt_ia_addr); } - - offset += sizeof(struct opt_ia_addr); } } - if (ia_type == OPT_IA_NA) { - ia_type = OPT_IA_TA; - goto ia_ta; - } - return NULL; + +err: + info("DHCPv6: requested address %s not on link", + inet_ntop(AF_INET6, &req_addr, buf, sizeof(buf))); + return ia; } /** diff --git a/util.h b/util.h index 0bf396a..582ef57 100644 --- a/util.h +++ b/util.h @@ -102,6 +102,9 @@ #define ARRAY_SIZE(a) ((int)(sizeof(a) / sizeof((a)[0]))) +#define foreach(item, array) \ + for ((item) = (array); (item) - (array) < ARRAY_SIZE(array); (item)++) + #define IN_INTERVAL(a, b, x) ((x) >= (a) && (x) <= (b)) #define FD_PROTO(x, proto) \ (IN_INTERVAL(c->proto.fd_min, c->proto.fd_max, (x)))-- David Gibson (he or they) | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you, not the other way | around. http://www.ozlabs.org/~dgibson