Include IPv6RA and DHCPv6 in the sorting of interfaces.

1 files changed, 69 insertions, 0 deletions

diff --git a/if.c b/if.c
index 7526b77a..de3693e7 100644
--- a/if.c
+++ b/if.c
@@ -588,3 +588,72 @@ if_domtu(const char *ifname, short int mtu)
 		return -1;
 	return ifr.ifr_mtu;
 }
+
+/* Interface comparer for working out ordering. */
+static int
+if_cmp(const struct interface *si, const struct interface *ti)
+{
+#ifdef INET
+	int r;
+#endif
+
+	if (D_STATE_RUNNING(si) && !D_STATE_RUNNING(ti))
+		return -1;
+	if (!D_STATE_RUNNING(si) && D_STATE_RUNNING(ti))
+		return 1;
+	if (RS_STATE_RUNNING(si) && !RS_STATE_RUNNING(ti))
+		return -1;
+	if (!RS_STATE_RUNNING(si) && RS_STATE_RUNNING(ti))
+		return 1;
+	if (D6_STATE_RUNNING(si) && !D6_STATE_RUNNING(ti))
+		return -1;
+	if (!D6_STATE_RUNNING(si) && D6_STATE_RUNNING(ti))
+		return 1;
+
+#ifdef INET
+	/* Special attention needed hereto due take states and IPv4LL. */
+	if ((r = ipv4_ifcmp(si, ti)) != 0)
+		return r;
+#endif
+
+	/* Then carrier status. */
+	if (si->carrier > ti->carrier)
+		return -1;
+	if (si->carrier < ti->carrier)
+		return 1;
+	/* Finally, metric */
+	if (si->metric < ti->metric)
+		return -1;
+	if (si->metric > ti->metric)
+		return 1;
+	return 0;
+}
+
+/* Sort the interfaces into a preferred order - best first, worst last. */
+void
+if_sortinterfaces(struct dhcpcd_ctx *ctx)
+{
+	struct if_head sorted;
+	struct interface *ifp, *ift;
+
+	if (ctx->ifaces == NULL ||
+	    (ifp = TAILQ_FIRST(ctx->ifaces)) == NULL ||
+	    TAILQ_NEXT(ifp, next) == NULL)
+		return;
+
+	TAILQ_INIT(&sorted);
+	TAILQ_REMOVE(ctx->ifaces, ifp, next);
+	TAILQ_INSERT_HEAD(&sorted, ifp, next);
+	while ((ifp = TAILQ_FIRST(ctx->ifaces))) {
+		TAILQ_REMOVE(ctx->ifaces, ifp, next);
+		TAILQ_FOREACH(ift, &sorted, next) {
+			if (if_cmp(ifp, ift) == -1) {
+				TAILQ_INSERT_BEFORE(ift, ifp, next);
+				break;
+			}
+		}
+		if (ift == NULL)
+			TAILQ_INSERT_TAIL(&sorted, ifp, next);
+	}
+	TAILQ_CONCAT(ctx->ifaces, &sorted, next);
+}