Improved DNS_LOCAL_HOSTLIST interface (bug #50325)

CHANGELOG

@@ -6,6 +6,9 @@ HISTORY
 
   ++ New features:
 
+  2017-02-17: Simon Goldschmidt
+  * Improved DNS_LOCAL_HOSTLIST interface
+
   2017-02-10: David van Moolenbroek
   * Implement UDP and RAW multicast support for IPv6 (core API, not netconn/sockets)
 

src/core/dns.c

@@ -280,6 +280,7 @@ DNS_LOCAL_HOSTLIST_STORAGE_PRE struct local_hostlist_entry local_hostlist_static
 #endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
 
 static void dns_init_local(void);
+static err_t dns_lookup_local(const char *hostname, ip_addr_t *addr LWIP_DNS_ADDRTYPE_ARG(u8_t dns_addrtype));
 #endif /* DNS_LOCAL_HOSTLIST */
 
 
@@ -430,6 +431,38 @@ dns_init_local(void)
 #endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC && defined(DNS_LOCAL_HOSTLIST_INIT) */
 }
 
+/**
+ * @ingroup dns
+ * Iterate the local host-list for a hostname.
+ *
+ * @param iterator_fn a function that is called for every entry in the local host-list
+ * @param iterator_arg 3rd argument passed to iterator_fn
+ * @return the number of entries in the local host-list
+ */
+size_t
+dns_local_iterate(dns_found_callback iterator_fn, void *iterator_arg)
+{
+  size_t i;
+#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC
+  struct local_hostlist_entry *entry = local_hostlist_dynamic;
+  i = 0;
+  while (entry != NULL) {
+    if (iterator_fn != NULL) {
+      iterator_fn(entry->name, &entry->addr, iterator_arg);
+    }
+    i++;
+    entry = entry->next;
+  }
+#else /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+  for (i = 0; i < LWIP_ARRAYSIZE(local_hostlist_static); i++) {
+    if (iterator_fn != NULL) {
+      iterator_fn(local_hostlist_static[i].name, &local_hostlist_static[i].addr, iterator_arg);
+    }
+  }
+#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+  return i;
+}
+
 /**
  * @ingroup dns
  * Scans the local host-list for a hostname.
@@ -437,8 +470,20 @@ dns_init_local(void)
  * @param hostname Hostname to look for in the local host-list
  * @param addr the first IP address for the hostname in the local host-list or
  *         IPADDR_NONE if not found.
+ * @param dns_addrtype - LWIP_DNS_ADDRTYPE_IPV4_IPV6: try to resolve IPv4 (ATTENTION: no fallback here!)
+ *                     - LWIP_DNS_ADDRTYPE_IPV6_IPV4: try to resolve IPv6 (ATTENTION: no fallback here!)
+ *                     - LWIP_DNS_ADDRTYPE_IPV4: try to resolve IPv4 only
+ *                     - LWIP_DNS_ADDRTYPE_IPV6: try to resolve IPv6 only
  * @return ERR_OK if found, ERR_ARG if not found
  */
+err_t
+dns_local_lookup(const char *hostname, ip_addr_t *addr, u8_t dns_addrtype)
+{
+  LWIP_UNUSED_ARG(dns_addrtype);
+  return dns_lookup_local(hostname, addr LWIP_DNS_ADDRTYPE_ARG(dns_addrtype));
+}
+
+/* Internal implementation for dns_local_lookup and dns_lookup */
 static err_t
 dns_lookup_local(const char *hostname, ip_addr_t *addr LWIP_DNS_ADDRTYPE_ARG(u8_t dns_addrtype))
 {
@@ -1434,9 +1479,9 @@ dns_gethostbyname(const char *hostname, ip_addr_t *addr, dns_found_callback foun
  *              ERR_INPROGRESS is returned!)
  * @param callback_arg argument to pass to the callback function
  * @param dns_addrtype - LWIP_DNS_ADDRTYPE_IPV4_IPV6: try to resolve IPv4 first, try IPv6 if IPv4 fails only
- *                      - LWIP_DNS_ADDRTYPE_IPV6_IPV4: try to resolve IPv6 first, try IPv4 if IPv6 fails only
- *                      - LWIP_DNS_ADDRTYPE_IPV4: try to resolve IPv4 only
- *                      - LWIP_DNS_ADDRTYPE_IPV6: try to resolve IPv6 only
+ *                     - LWIP_DNS_ADDRTYPE_IPV6_IPV4: try to resolve IPv6 first, try IPv4 if IPv6 fails only
+ *                     - LWIP_DNS_ADDRTYPE_IPV4: try to resolve IPv4 only
+ *                     - LWIP_DNS_ADDRTYPE_IPV6: try to resolve IPv6 only
  */
 err_t
 dns_gethostbyname_addrtype(const char *hostname, ip_addr_t *addr, dns_found_callback found,

src/include/lwip/dns.h

@@ -112,10 +112,14 @@ err_t            dns_gethostbyname_addrtype(const char *hostname, ip_addr_t *add
                                    u8_t dns_addrtype);
 
 
-#if DNS_LOCAL_HOSTLIST && DNS_LOCAL_HOSTLIST_IS_DYNAMIC
+#if DNS_LOCAL_HOSTLIST
+size_t         dns_local_iterate(dns_found_callback iterator_fn, void *iterator_arg);
+err_t          dns_local_lookup(const char *hostname, ip_addr_t *addr, u8_t dns_addrtype);
+#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC
 int            dns_local_removehost(const char *hostname, const ip_addr_t *addr);
 err_t          dns_local_addhost(const char *hostname, const ip_addr_t *addr);
-#endif /* DNS_LOCAL_HOSTLIST && DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+#endif /* DNS_LOCAL_HOSTLIST */
 
 #ifdef __cplusplus
 }