add a test

test/core/surface/server_chttp2_test.c

@@ -32,7 +32,14 @@
  */
 
 #include <grpc/grpc.h>
+#include <grpc/grpc_security.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/host_port.h>
 #include <grpc/support/log.h>
+#include <grpc/support/time.h>
+#include "src/core/security/credentials.h"
+#include "src/core/tsi/fake_transport_security.h"
+#include "test/core/util/port.h"
 #include "test/core/util/test_config.h"
 
 void test_unparsable_target(void) {
@@ -40,10 +47,31 @@ void test_unparsable_target(void) {
   GPR_ASSERT(port == 0);
 }
 
+void test_add_same_port_twice() {
+  int port = grpc_pick_unused_port_or_die();
+  char *addr = NULL;
+  grpc_completion_queue *cq = grpc_completion_queue_create(NULL);
+  grpc_server *server = grpc_server_create(NULL, NULL);
+  grpc_server_credentials *fake_creds =
+      grpc_fake_transport_security_server_credentials_create();
+  gpr_join_host_port(&addr, "localhost", port);
+  GPR_ASSERT(grpc_server_add_secure_http2_port(server, addr, fake_creds));
+  GPR_ASSERT(grpc_server_add_secure_http2_port(server, addr, fake_creds) == 0);
+
+  grpc_server_credentials_release(fake_creds);
+  gpr_free(addr);
+  grpc_server_shutdown_and_notify(server, cq, NULL);
+  grpc_completion_queue_pluck(cq, NULL, gpr_inf_future(GPR_CLOCK_REALTIME),
+                              NULL);
+  grpc_server_destroy(server);
+  grpc_completion_queue_destroy(cq);
+}
+
 int main(int argc, char **argv) {
   grpc_test_init(argc, argv);
   grpc_init();
   test_unparsable_target();
+  test_add_same_port_twice();
   grpc_shutdown();
   return 0;
 }