--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/third_party/libuv/test/test-embed.c	Wed Jan 14 19:39:52 2026 -0800
@@ -0,0 +1,79 @@
+/* Copyright libuv project contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "uv.h"
+#include "task.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+
+#if !defined(_WIN32) && !defined(_AIX)
+#include <poll.h>
+#endif
+
+static uv_async_t async;
+static uv_barrier_t barrier;
+
+
+static void thread_main(void* arg) {
+  ASSERT_LE(0, uv_barrier_wait(&barrier));
+  uv_sleep(250);
+  ASSERT_OK(uv_async_send(&async));
+}
+
+
+static void async_cb(uv_async_t* handle) {
+  uv_close((uv_handle_t*) handle, NULL);
+}
+
+
+TEST_IMPL(embed) {
+  uv_thread_t thread;
+  uv_loop_t* loop;
+
+  loop = uv_default_loop();
+  ASSERT_OK(uv_async_init(loop, &async, async_cb));
+  ASSERT_OK(uv_barrier_init(&barrier, 2));
+  ASSERT_OK(uv_thread_create(&thread, thread_main, NULL));
+  ASSERT_LE(0, uv_barrier_wait(&barrier));
+
+  while (uv_loop_alive(loop)) {
+#if defined(_WIN32) || defined(_AIX)
+    ASSERT_LE(0, uv_run(loop, UV_RUN_ONCE));
+#else
+    int rc;
+    do {
+      struct pollfd p;
+      p.fd = uv_backend_fd(loop);
+      p.events = POLLIN;
+      p.revents = 0;
+      rc = poll(&p, 1, uv_backend_timeout(loop));
+    } while (rc == -1 && errno == EINTR);
+    ASSERT_LE(0, uv_run(loop, UV_RUN_NOWAIT));
+#endif
+  }
+
+  ASSERT_OK(uv_thread_join(&thread));
+  uv_barrier_destroy(&barrier);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}