gnrc_netif: introduce gnrc_netif_6lo pseudo-module for 6LoWPAN members

This aims to reduce circular dependencies in GNRC.

Makefile.dep

@@ -274,6 +274,9 @@ ifneq (,$(filter gnrc_sixlowpan,$(USEMODULE)))
   DEFAULT_MODULE += auto_init_gnrc_sixlowpan
   USEMODULE += gnrc_nettype_sixlowpan
   USEMODULE += sixlowpan
+  ifneq (,$(filter gnrc_netif,$(USEMODULE)))
+    USEMODULE += gnrc_netif_6lo
+  endif
 endif
 
 ifneq (,$(filter gnrc_sixlowpan_ctx,$(USEMODULE)))

makefiles/pseudomodules.inc.mk

@@ -33,6 +33,7 @@ PSEUDOMODULES += gnrc_netapi_callbacks
 PSEUDOMODULES += gnrc_netapi_mbox
 PSEUDOMODULES += gnrc_netif_events
 PSEUDOMODULES += gnrc_pktbuf_cmd
+PSEUDOMODULES += gnrc_netif_6lo
 PSEUDOMODULES += gnrc_netif_cmd_%
 PSEUDOMODULES += gnrc_netif_dedup
 PSEUDOMODULES += gnrc_nettype_%

pkg/nimble/netif/nimble_netif.c

@@ -94,11 +94,11 @@ static void _netif_init(gnrc_netif_t *netif)
     /* save the threads context pointer, so we can set its flags */
     _netif_thread = (thread_t *)thread_get(thread_getpid());
 
-#ifdef MODULE_GNRC_SIXLOWPAN
+#if IS_USED(MODULE_GNRC_NETIF_6LO)
     /* we disable fragmentation for this device, as the L2CAP layer takes care
      * of this */
     _nimble_netif->sixlo.max_frag_size = 0;
-#endif
+#endif  /* IS_USED(MODULE_GNRC_NETIF_6LO) */
 }
 
 static int _send_pkt(nimble_netif_conn_t *conn, gnrc_pktsnip_t *pkt)

sys/include/net/gnrc/netif.h

@@ -38,7 +38,7 @@
 #if IS_USED(MODULE_GNRC_NETIF_LORAWAN)
 #include "net/gnrc/netif/lorawan.h"
 #endif
-#ifdef MODULE_GNRC_SIXLOWPAN
+#if IS_USED(MODULE_GNRC_NETIF_6LO)
 #include "net/gnrc/netif/6lo.h"
 #endif
 #if defined(MODULE_GNRC_NETIF_DEDUP) && (GNRC_NETIF_L2ADDR_MAXLEN > 0)
@@ -129,7 +129,7 @@ typedef struct {
     gnrc_netif_dedup_t last_pkt;
 #endif
 #endif
-#if defined(MODULE_GNRC_SIXLOWPAN) || DOXYGEN
+#if IS_USED(MODULE_GNRC_NETIF_6LO) || defined(DOXYGEN)
     gnrc_netif_6lo_t sixlo;                 /**< 6Lo component */
 #endif
     uint8_t cur_hl;                         /**< Current hop-limit for out-going packets */

sys/net/gnrc/netif/gnrc_netif.c

@@ -1296,14 +1296,14 @@ static void _test_options(gnrc_netif_t *netif)
             assert((IEEE802154_SHORT_ADDRESS_LEN == netif->l2addr_len) ||
                    (IEEE802154_LONG_ADDRESS_LEN == netif->l2addr_len));
 #ifdef MODULE_GNRC_IPV6
-#ifdef MODULE_GNRC_SIXLOWPAN
+#if IS_USED(MODULE_GNRC_NETIF_6LO)
             assert(netif->ipv6.mtu == IPV6_MIN_MTU);
             assert(netif->sixlo.max_frag_size > 0);
             assert(-ENOTSUP != netif->dev->driver->get(netif->dev, NETOPT_PROTO,
                                                        &tmp, sizeof(tmp)));
-#else   /* MODULE_GNRC_SIXLOWPAN */
+#else   /* IS_USED(MODULE_GNRC_NETIF_6LO) */
             assert(netif->ipv6.mtu < UINT16_MAX);
-#endif  /* MODULE_GNRC_SIXLOWPAN */
+#endif  /* IS_USED(MODULE_GNRC_NETIF_6LO) */
 #endif  /* MODULE_GNRC_IPV6 */
 #ifdef MODULE_GNRC_SIXLOWPAN_ND
             assert((netif->device_type != NETDEV_TYPE_IEEE802154) ||

sys/net/gnrc/netif/gnrc_netif_device_type.c

@@ -144,12 +144,12 @@ void gnrc_netif_ipv6_init_mtu(gnrc_netif_t *netif)
             res = dev->driver->get(dev, NETOPT_MAX_PDU_SIZE,
                                    &tmp, sizeof(tmp));
             assert(res == sizeof(tmp));
-#ifdef MODULE_GNRC_SIXLOWPAN
+#if IS_USED(MODULE_GNRC_NETIF_6LO)
             netif->ipv6.mtu = MAX(IPV6_MIN_MTU, tmp);
             netif->sixlo.max_frag_size = tmp;
-#else
+#else   /* IS_USED(MODULE_GNRC_NETIF_6LO) */
             netif->ipv6.mtu = tmp;
-#endif
+#endif  /* IS_USED(MODULE_GNRC_NETIF_6LO) */
             break;
 #endif  /* defined(MODULE_NETDEV_IEEE802154) || defined(MODULE_NRFMIN) || \
          * defined(MODULE_XBEE) || defined(MODULE_ESP_NOW) */