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.

diff --git a/src/dhcpcd.c b/src/dhcpcd.c
index fa5d5d597292e117b3db77047c2a294db5dcdd25..ecff2e57cccb738e7b07c173ad4449e5f5513589 100644 (file)
--- a/src/dhcpcd.c
+++ b/src/dhcpcd.c
@@ -652,25 +652,6 @@ 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)
 {
@@ -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);
 }
 

diff --git a/src/if-bsd.c b/src/if-bsd.c
index e608c8e6829e478267df8d97fdef40b85da6da3c..cb7cce596a23a1909b8e24cb6be140e698d75052 100644 (file)
--- a/src/if-bsd.c
+++ b/src/if-bsd.c
@@ -203,28 +203,19 @@ if_closesockets_os(struct dhcpcd_ctx *ctx)
                close(priv->pf_inet6_fd);
 }
 
-static int
-if_carrier_flags(struct interface *ifp, unsigned int flags)
+int
+if_carrier(struct interface *ifp)
 {
        struct ifmediareq ifmr = { .ifm_status = 0 };
 
        strlcpy(ifmr.ifm_name, ifp->name, sizeof(ifmr.ifm_name));
        if (ioctl(ifp->ctx->pf_inet_fd, SIOCGIFMEDIA, &ifmr) == -1 ||
            !(ifmr.ifm_status & IFM_AVALID))
-               return flags & IFF_RUNNING ? LINK_UP : LINK_UNKNOWN;
+               return LINK_UNKNOWN;
 
        return (ifmr.ifm_status & IFM_ACTIVE) ? LINK_UP : LINK_DOWN;
 }
 
-int
-if_carrier(struct interface *ifp)
-{
-
-       if (if_getflags(ifp) == -1)
-               return LINK_UNKNOWN;
-       return if_carrier_flags(ifp, ifp->flags);
-}
-
 static void
 if_linkaddr(struct sockaddr_dl *sdl, const struct interface *ifp)
 {
@@ -1009,33 +1000,24 @@ if_ifinfo(struct dhcpcd_ctx *ctx, const struct if_msghdr *ifm)
 {
        struct interface *ifp;
        int link_state;
-       unsigned int flags;
 
        if ((ifp = if_findindex(ctx->ifaces, ifm->ifm_index)) == NULL)
                return;
 
-       flags = (unsigned int)ifm->ifm_flags;
        switch (ifm->ifm_data.ifi_link_state) {
        case LINK_STATE_UNKNOWN:
-               /* In theory this is only set when an interface is first
-                * initiaised.
-                * However whilst some drivers report an active link
-                * via SIOCGIFMEDIA, they don't bother to announce it
-                * via a routing message. */
-               if (ifp->wireless) /* Wireless needs to work correctly. */
-                       link_state = LINK_DOWN;
-               else
-                       link_state = if_carrier_flags(ifp, flags);
+               link_state = LINK_UNKNOWN;
                break;
        case LINK_STATE_UP:
-               link_state = ifm->ifm_flags & IFF_UP ? LINK_UP : LINK_DOWN;
+               link_state = LINK_UP;
                break;
        default:
                link_state = LINK_DOWN;
                break;
        }
 
-       dhcpcd_handlecarrier(ctx, link_state, flags, ifp->name);
+       dhcpcd_handlecarrier(ctx, link_state,
+           (unsigned int)ifm->ifm_flags, ifp->name);
 }
 
 static void