dns-domain: simplify dns_name_is_root() and dns_name_is_single_label()

Let's change the return value to bool. If we encounter an error while
parsing, return "false" instead of the actual parsing error, after all
the specified hostname does not qualify for what the function is
supposed to test.

Dealing with the additional error codes was always cumbersome, and
easily misused, like for example in the DHCP code.

Let's also rename the functions from dns_name_root() to
dns_name_is_root(), to indicate that this function checks something and
returns a bool. Similar for dns_name_is_signal_label().

1 files changed, 15 insertions, 15 deletions

diff --git a/src/test/test-dns-domain.c b/src/test/test-dns-domain.c
index b76a31a549..cefe8698c8 100644
--- a/src/test/test-dns-domain.c
+++ b/src/test/test-dns-domain.c
@@ -246,21 +246,21 @@ static void test_dns_name_endswith(void) {
         test_dns_name_endswith_one("x.y\001.z", "waldo", -EINVAL);
 }
 
-static void test_dns_name_root(void) {
-        assert_se(dns_name_root("") == true);
-        assert_se(dns_name_root(".") == true);
-        assert_se(dns_name_root("xxx") == false);
-        assert_se(dns_name_root("xxx.") == false);
-        assert_se(dns_name_root("..") == -EINVAL);
+static void test_dns_name_is_root(void) {
+        assert_se(dns_name_is_root(""));
+        assert_se(dns_name_is_root("."));
+        assert_se(!dns_name_is_root("xxx"));
+        assert_se(!dns_name_is_root("xxx."));
+        assert_se(!dns_name_is_root(".."));
 }
 
-static void test_dns_name_single_label(void) {
-        assert_se(dns_name_single_label("") == false);
-        assert_se(dns_name_single_label(".") == false);
-        assert_se(dns_name_single_label("..") == -EINVAL);
-        assert_se(dns_name_single_label("x") == true);
-        assert_se(dns_name_single_label("x.") == true);
-        assert_se(dns_name_single_label("xx.yy") == false);
+static void test_dns_name_is_single_label(void) {
+        assert_se(!dns_name_is_single_label(""));
+        assert_se(!dns_name_is_single_label("."));
+        assert_se(!dns_name_is_single_label(".."));
+        assert_se(dns_name_is_single_label("x"));
+        assert_se(dns_name_is_single_label("x."));
+        assert_se(!dns_name_is_single_label("xx.yy"));
 }
 
 static void test_dns_name_reverse_one(const char *address, const char *name) {
@@ -436,8 +436,8 @@ int main(int argc, char *argv[]) {
         test_dns_name_equal();
         test_dns_name_endswith();
         test_dns_name_between();
-        test_dns_name_root();
-        test_dns_name_single_label();
+        test_dns_name_is_root();
+        test_dns_name_is_single_label();
         test_dns_name_reverse();
         test_dns_name_concat();
         test_dns_name_is_valid();