Fix declarations in port.h to not be ambiguous in C due to K&R.

Also actually add the port parameter to grpc_recycle_unused_port.

Also remove the downsizing gpr_realloc in the recycle codepath, which is
unnecessary and can free the pointer.

test/core/util/port.h

@@ -40,16 +40,16 @@ extern "C" {
 
 /* pick a port number that is currently unused by either tcp or udp. return
    0 on failure. */
-int grpc_pick_unused_port();
+int grpc_pick_unused_port(void);
 /* pick a port number that is currently unused by either tcp or udp. abort
    on failure. */
-int grpc_pick_unused_port_or_die();
+int grpc_pick_unused_port_or_die(void);
 
 /* Return a port which was previously returned by grpc_pick_unused_port().
  * Implementations of grpc_pick_unused_port() backed by a portserver may limit
  * the total number of ports available; this lets a binary return its allocated
  * ports back to the server if it is going to allocate a large number. */
-void grpc_recycle_unused_port();
+void grpc_recycle_unused_port(int port);
 
 #ifdef __cplusplus
 }

test/core/util/port_posix.c

@@ -73,7 +73,6 @@ static int free_chosen_port(int port) {
   int found = 0;
   size_t found_at = 0;
   char *env = gpr_getenv("GRPC_TEST_PORT_SERVER");
-  if (env != NULL) {
   /* Find the port and erase it from the list, then tell the server it can be
      freed. */
   for (i = 0; i < num_chosen_ports; i++) {
@@ -85,9 +84,9 @@ static int free_chosen_port(int port) {
   }
   if (found) {
     chosen_ports[found_at] = chosen_ports[num_chosen_ports - 1];
-      grpc_free_port_using_server(env, port);
     num_chosen_ports--;
-      chosen_ports = gpr_realloc(chosen_ports, sizeof(int) * num_chosen_ports);
+    if (env) {
+      grpc_free_port_using_server(env, port);
     }
   }
   return found;

test/core/util/port_windows.c

@@ -90,7 +90,6 @@ static int free_chosen_port(int port) {
       chosen_ports[found_at] = chosen_ports[num_chosen_ports - 1];
       grpc_free_port_using_server(env, port);
       num_chosen_ports--;
-      chosen_ports = gpr_realloc(chosen_ports, sizeof(int) * num_chosen_ports);
     }
   }
   return found;