UBF is also required for synchronous name resolution (ruby#12156)

`rb_thread_call_without_gvl2` is used to wait for the results of name resolution and connection attempts.
When there is only one address family to resolve, the necessary resources were not being passed to the UBF.
With this change, the handling of resources has been revised and organized to work consistently, whether there are two address families to resolve or only one.

Author: shioimm

ext/socket/ipsocket.c

@@ -593,6 +593,31 @@ init_fast_fallback_inetsock_internal(VALUE v)
     arg->connection_attempt_fds = allocate_connection_attempt_fds(additional_capacity);
     arg->connection_attempt_fds_size = 0;
 
+    if (pipe(pipefd) != 0) rb_syserr_fail(errno, "pipe(2)");
+    hostname_resolution_waiter = pipefd[0];
+    int waiter_flags = fcntl(hostname_resolution_waiter, F_GETFL, 0);
+    if (waiter_flags < 0) rb_syserr_fail(errno, "fcntl(2)");
+    if ((fcntl(hostname_resolution_waiter, F_SETFL, waiter_flags | O_NONBLOCK)) < 0) {
+        rb_syserr_fail(errno, "fcntl(2)");
+    }
+
+    hostname_resolution_notifier = pipefd[1];
+    wait_arg.readfds = &readfds;
+
+    arg->getaddrinfo_shared = allocate_fast_fallback_getaddrinfo_shared();
+    if (!arg->getaddrinfo_shared) rb_syserr_fail(errno, "calloc(3)");
+
+    arg->getaddrinfo_shared->lock = calloc(1, sizeof(rb_nativethread_lock_t));
+    if (!arg->getaddrinfo_shared->lock) rb_syserr_fail(errno, "calloc(3)");
+    rb_nativethread_lock_initialize(arg->getaddrinfo_shared->lock);
+
+    arg->getaddrinfo_shared->notify = hostname_resolution_notifier;
+    arg->getaddrinfo_shared->wait = hostname_resolution_waiter;
+    arg->getaddrinfo_shared->connection_attempt_fds = arg->connection_attempt_fds;
+    arg->getaddrinfo_shared->connection_attempt_fds_size = arg->connection_attempt_fds_size;
+    arg->getaddrinfo_shared->cancelled = false;
+    wait_arg.cancelled = false;
+
     struct timeval resolution_delay_storage;
     struct timeval *resolution_delay_expires_at = NULL;
     struct timeval connection_attempt_delay_strage;
@@ -605,6 +630,10 @@ init_fast_fallback_inetsock_internal(VALUE v)
 
     /* start of hostname resolution */
     if (arg->family_size == 1) {
+        arg->getaddrinfo_shared->node = NULL;
+        arg->getaddrinfo_shared->service = NULL;
+        arg->getaddrinfo_shared->refcount = 1;
+
         int family = arg->families[0];
         arg->remote.res = rsock_addrinfo(
             arg->remote.host,
@@ -624,35 +653,10 @@ init_fast_fallback_inetsock_internal(VALUE v)
             resolution_store.v6.finished = true;
         }
         resolution_store.is_all_finised = true;
-        wait_arg.readfds = NULL;
     } else {
-        if (pipe(pipefd) != 0) rb_syserr_fail(errno, "pipe(2)");
-        hostname_resolution_waiter = pipefd[0];
-        int waiter_flags = fcntl(hostname_resolution_waiter, F_GETFL, 0);
-        if (waiter_flags < 0) rb_syserr_fail(errno, "fcntl(2)");
-        if ((fcntl(hostname_resolution_waiter, F_SETFL, waiter_flags | O_NONBLOCK)) < 0) {
-            rb_syserr_fail(errno, "fcntl(2)");
-        }
-
-        hostname_resolution_notifier = pipefd[1];
-        wait_arg.readfds = &readfds;
-
-        arg->getaddrinfo_shared = allocate_fast_fallback_getaddrinfo_shared();
-        if (!arg->getaddrinfo_shared) rb_syserr_fail(errno, "calloc(3)");
-
-        arg->getaddrinfo_shared->lock = calloc(1, sizeof(rb_nativethread_lock_t));
-        if (!arg->getaddrinfo_shared->lock) rb_syserr_fail(errno, "calloc(3)");
-        rb_nativethread_lock_initialize(arg->getaddrinfo_shared->lock);
-
         arg->getaddrinfo_shared->node = arg->hostp ? strdup(arg->hostp) : NULL;
         arg->getaddrinfo_shared->service = strdup(arg->portp);
         arg->getaddrinfo_shared->refcount = arg->family_size + 1;
-        arg->getaddrinfo_shared->notify = hostname_resolution_notifier;
-        arg->getaddrinfo_shared->wait = hostname_resolution_waiter;
-        arg->getaddrinfo_shared->connection_attempt_fds = arg->connection_attempt_fds;
-        arg->getaddrinfo_shared->connection_attempt_fds_size = arg->connection_attempt_fds_size;
-        arg->getaddrinfo_shared->cancelled = false;
-        wait_arg.cancelled = false;
 
         for (int i = 0; i < arg->family_size; i++) {
             arg->getaddrinfo_entries[i] = allocate_fast_fallback_getaddrinfo_entry();