BSD: Simplify carrier detection once more.

RTM_IFINFO messages now send the un-molested link status to
the main carrier handler which no longer polls on LINK_UNKNOWN.
Instead, we check carrier status directly, which if unsupported
we instead interface flags.

This is 2019, all interface drivers should report link status
correctly via RTM_IFINFO messages and trying to constantly work
around this is error prone and time consuming.

1 files changed, 10 insertions, 59 deletions

diff --git a/src/dhcpcd.c b/src/dhcpcd.c
index fa5d5d59..ecff2e57 100644
--- a/src/dhcpcd.c
+++ b/src/dhcpcd.c
@@ -653,25 +653,6 @@ configure_interface(struct interface *ifp, int argc, char **argv,
 }
 
 static void
-dhcpcd_pollup(void *arg)
-{
-	struct interface *ifp = arg;
-	int carrier;
-
-	carrier = if_carrier(ifp); /* will set ifp->flags */
-	if (carrier == LINK_UP && !(ifp->flags & IFF_UP)) {
-		struct timespec tv;
-
-		tv.tv_sec = 0;
-		tv.tv_nsec = IF_POLL_UP * NSEC_PER_MSEC;
-		eloop_timeout_add_tv(ifp->ctx->eloop, &tv, dhcpcd_pollup, ifp);
-		return;
-	}
-
-	dhcpcd_handlecarrier(ifp->ctx, carrier, ifp->flags, ifp->name);
-}
-
-static void
 dhcpcd_initstate2(struct interface *ifp, unsigned long long options)
 {
 	struct if_options *ifo;
@@ -724,35 +705,19 @@ dhcpcd_handlecarrier(struct dhcpcd_ctx *ctx, int carrier, unsigned int flags,
 	    !ifp->active)
 		return;
 
-	switch(carrier) {
-	case LINK_UNKNOWN:
-		carrier = if_carrier(ifp); /* will set ifp->flags */
-		break;
-	case LINK_UP:
-		/* we have a carrier! Still need to check for IFF_UP */
-		if (flags & IFF_UP)
+	if (carrier == LINK_UNKNOWN) {
+		if (ifp->wireless) {
+			carrier = LINK_DOWN;
 			ifp->flags = flags;
-		else {
-			/* So we need to poll for IFF_UP as there is no
-			 * kernel notification when it's set. */
-			dhcpcd_pollup(ifp);
-			return;
-		}
-		break;
-	default:
+		} else
+			carrier = if_carrier(ifp);
+	} else
 		ifp->flags = flags;
-	}
-
-	/* If we here, we don't need to poll for IFF_UP any longer
-	 * if generated by a kernel event. */
-	eloop_timeout_delete(ifp->ctx->eloop, dhcpcd_pollup, ifp);
+	if (carrier == LINK_UNKNOWN)
+		carrier = (ifp->flags & (IFF_UP | IFF_RUNNING)) ==
+		    (IFF_UP & IFF_RUNNING) ? LINK_UP : LINK_DOWN;
 
-	if (carrier == LINK_UNKNOWN) {
-		if (errno != ENOTTY && errno != ENXIO) {
-			/* Don't log an error if interface departed */
-			logerr("%s: %s", ifp->name, __func__);
-		}
-	} else if (carrier == LINK_DOWN || (ifp->flags & IFF_UP) == 0) {
+	if (carrier == LINK_DOWN || (ifp->flags & IFF_UP) == 0) {
 		if (ifp->carrier != LINK_DOWN) {
 			if (ifp->carrier == LINK_UP)
 				loginfox("%s: carrier lost", ifp->name);
@@ -987,20 +952,6 @@ dhcpcd_prestartinterface(void *arg)
 	    )
 		logerr("%s: %s", __func__, ifp->name);
 
-	if (ifp->options->options & DHCPCD_LINK &&
-	    ifp->carrier == LINK_UNKNOWN)
-	{
-		int carrier;
-
-		if ((carrier = if_carrier(ifp)) != LINK_UNKNOWN) {
-			dhcpcd_handlecarrier(ifp->ctx, carrier,
-			    ifp->flags, ifp->name);
-			return;
-		}
-		loginfox("%s: unknown carrier, waiting for interface flags",
-		    ifp->name);
-	}
-
 	dhcpcd_startinterface(ifp);
 }