Add sigisemptyset.c to libc (#20755)

Fixes: #20753

Author: sbc100

test/test_signals.c renamed to test/core/test_signals.c

@@ -144,11 +144,21 @@ void test_sigaction() {
   assert(action2.sa_handler == handler1);
 }
 
+void test_sigemptyset() {
+  sigset_t s = { 0 };
+  assert(sigisemptyset(&s));
+  sigaddset(&s, SIGUSR1);
+  assert(!sigisemptyset(&s));
+  sigemptyset(&s);
+  assert(sigisemptyset(&s));
+}
+
 int main() {
   test_sigaction();
   test_bad_signal();
   test_raise_sigusr1();
   test_sigpenging();
   test_sigwaitinfo();
+  test_sigemptyset();
   return 0;
 }

test/test_signals.out renamed to test/core/test_signals.out

@@ -6199,7 +6199,7 @@ def test_sigalrm(self):
     self.do_runf('test_sigalrm.c', 'Received alarm!')
 
   def test_signals(self):
-    self.do_core_test(test_file('test_signals.c'))
+    self.do_core_test('test_signals.c')
 
   @parameterized({
     'sigint': (EM_SIGINT, 128 + EM_SIGINT, True),

test/test_core.py

@@ -1220,6 +1220,7 @@ def get_files(self):
           'sigaddset.c',
           'sigdelset.c',
           'sigemptyset.c',
+          'sigisemptyset.c',
           'sigfillset.c',
           'sigismember.c',
           'siginterrupt.c',