Move handling of address/netmask pairs from ifquery into library.

Signed-off-by: Maximilian Wilhelm <max@sdn.clinic>

cmd/ifquery.c

@@ -92,31 +92,6 @@ print_interface_dot(struct lif_dict *collection, struct lif_interface *iface, st
 	}
 }
 
-static inline size_t
-count_set_bits(const char *netmask)
-{
-	/* netmask set to CIDR length */
-	if (strchr(netmask, '.') == NULL)
-		return strtol(netmask, NULL, 10);
-
-	size_t r = 0;
-	struct in_addr in;
-
-	if (inet_pton(AF_INET, netmask, &in) == 0)
-		return r;
-
-	/* take the IP, put it in host endian order, and
-	 * flip it so that all the set bits are set to the right.
-	 * then we can simply count down from 32 and right-shift
-	 * until the bit field is all zero.
-	 */
-	unsigned int bits = htonl(in.s_addr);
-	for (bits = ~bits, r = 32; bits; bits >>= 1, r--)
-		;
-
-	return r;
-}
-
 void
 print_interface_property(struct lif_interface *iface, const char *property)
 {
@@ -132,26 +107,10 @@ print_interface_property(struct lif_interface *iface, const char *property)
 
 		if (printing_address)
 		{
-			struct lif_address *addr = entry->data;
-			size_t orig_netmask = addr->netmask;
-
-			if (!addr->netmask)
-			{
-				/* if fallback netmask is not set, default to 255.255.255.0 */
-				addr->netmask = 24;
-
-				struct lif_dict_entry *entry = lif_dict_find(&iface->vars, "netmask");
-				if (entry != NULL)
-					addr->netmask = count_set_bits(entry->data);
-			}
-
 			char addr_buf[512];
-
+			if (!lif_address_format_cidr(iface, entry, addr_buf, sizeof(addr_buf)))
-			if (!lif_address_unparse(addr, addr_buf, sizeof addr_buf, true))
 				continue;
 
-			addr->netmask = orig_netmask;
-
 			printf("%s\n", addr_buf);
 		}
 		else

libifupdown/interface.c

@@ -58,6 +58,57 @@ lif_address_unparse(const struct lif_address *address, char *buf, size_t buflen,
 	return true;
 }
 
+static inline size_t
+count_set_bits(const char *netmask)
+{
+        /* netmask set to CIDR length */
+	if (strchr(netmask, '.') == NULL)
+		return strtol(netmask, NULL, 10);
+
+	size_t r = 0;
+	struct in_addr in;
+
+	if (inet_pton(AF_INET, netmask, &in) == 0)
+		return r;
+
+	/* take the IP, put it in host endian order, and
+	 * flip it so that all the set bits are set to the right.
+	 * then we can simply count down from 32 and right-shift
+	 * until the bit field is all zero.
+	 */
+	unsigned int bits = htonl(in.s_addr);
+	for (bits = ~bits, r = 32; bits; bits >>= 1, r--)
+		;
+
+	return r;
+}
+
+bool
+lif_address_format_cidr(struct lif_interface *iface, struct lif_dict_entry *entry, char *buf, size_t buflen)
+{
+	struct lif_address *addr = entry->data;
+	size_t orig_netmask = addr->netmask;
+
+	if (!addr->netmask)
+	{
+		/* if netmask is not set, default to 255.255.255.0, ifupdown does so too */
+		addr->netmask = 24;
+
+		struct lif_dict_entry *entry = lif_dict_find(&iface->vars, "netmask");
+		if (entry != NULL)
+			addr->netmask = count_set_bits(entry->data);
+	}
+
+	if (!lif_address_unparse(addr, buf, buflen, true))
+	{
+		addr->netmask = orig_netmask;
+		return false;
+	}
+
+	addr->netmask = orig_netmask;
+	return true;
+}
+
 void
 lif_interface_init(struct lif_interface *interface, const char *ifname)
 {

libifupdown/interface.h

@@ -32,9 +32,6 @@ struct lif_address {
 	int domain;
 };
 
-extern bool lif_address_parse(struct lif_address *address, const char *presentation);
-extern bool lif_address_unparse(const struct lif_address *address, char *buf, size_t buflen, bool with_netmask);
-
 /*
  * Interfaces are contained in a dictionary, with the interfaces mapped by
  * interface name to their `struct lif_interface`.
@@ -68,6 +65,10 @@ struct lif_interface {
 #define LIF_INTERFACE_COLLECTION_FOREACH_SAFE(iter, iter_next, collection) \
 	LIF_DICT_FOREACH_SAFE((iter), (iter_next), (collection))
 
+extern bool lif_address_parse(struct lif_address *address, const char *presentation);
+extern bool lif_address_unparse(const struct lif_address *address, char *buf, size_t buflen, bool with_netmask);
+extern bool lif_address_format_cidr(struct lif_interface *iface, struct lif_dict_entry *entry, char *buf, size_t buflen);
+
 extern void lif_interface_init(struct lif_interface *interface, const char *ifname);
 extern bool lif_interface_address_add(struct lif_interface *interface, const char *address);
 extern void lif_interface_address_delete(struct lif_interface *interface, const char *address);