dns: Verify setting/getting servers in unit test

test/unit/core/test_dns.c

@@ -0,0 +1,52 @@
+#include "test_dns.h"
+
+#include "lwip/dns.h"
+
+/* Setups/teardown functions */
+
+static void
+dns_setup(void)
+{
+}
+
+static void
+dns_teardown(void)
+{
+}
+
+/* Test functions */
+
+START_TEST(test_dns_set_get_server)
+{
+  int i;
+  LWIP_UNUSED_ARG(_i);
+
+  for (i = 0; i < 256; i++) {
+    ip_addr_t server;
+    /* Should return a zeroed address for any index */
+    fail_unless(dns_getserver(i));
+    fail_unless(ip_addr_isany(dns_getserver(i)));
+
+    /* Should accept setting address for any index, and ignore if out of range */
+    IP_ADDR4(&server, 10, 0, 0, i);
+    dns_setserver(i, &server);
+    fail_unless(dns_getserver(i));
+    if (i < DNS_MAX_SERVERS) {
+      /* ip_addr_cmp returns 1 if they match. */
+      fail_unless(ip_addr_cmp(dns_getserver(i), &server) == 1);
+    } else {
+      fail_unless(ip_addr_isany(dns_getserver(i)));
+    }
+  }
+}
+END_TEST
+
+/** Create the suite including all tests for this module */
+Suite *
+dns_suite(void)
+{
+  testfunc tests[] = {
+    TESTFUNC(test_dns_set_get_server)
+  };
+  return create_suite("DNS", tests, sizeof(tests)/sizeof(testfunc), dns_setup, dns_teardown);
+}