--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/third_party/libuv/test/benchmark-ping-pongs.c	Wed Jan 14 19:39:52 2026 -0800
@@ -0,0 +1,221 @@
+/* Copyright Joyent, Inc. and other Node 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 <stdlib.h>
+#include <stdio.h>
+
+/* Run the benchmark for this many ms */
+#define TIME 5000
+
+
+typedef struct {
+  int pongs;
+  int state;
+  uv_tcp_t tcp;
+  uv_connect_t connect_req;
+  uv_shutdown_t shutdown_req;
+} pinger_t;
+
+typedef struct buf_s {
+  uv_buf_t uv_buf_t;
+  struct buf_s* next;
+} buf_t;
+
+
+static char PING[] = "PING\n";
+
+static uv_loop_t* loop;
+
+static buf_t* buf_freelist = NULL;
+static int pinger_shutdown_cb_called;
+static int completed_pingers = 0;
+static int64_t start_time;
+
+
+static void buf_alloc(uv_handle_t* tcp, size_t size, uv_buf_t* buf) {
+  buf_t* ab;
+
+  ab = buf_freelist;
+  if (ab != NULL)
+    buf_freelist = ab->next;
+  else {
+    ab = malloc(size + sizeof(*ab));
+    ab->uv_buf_t.len = size;
+    ab->uv_buf_t.base = (char*) (ab + 1);
+  }
+
+  *buf = ab->uv_buf_t;
+}
+
+
+static void buf_free(const uv_buf_t* buf) {
+  buf_t* ab = (buf_t*) buf->base - 1;
+  ab->next = buf_freelist;
+  buf_freelist = ab;
+}
+
+
+static void pinger_close_cb(uv_handle_t* handle) {
+  pinger_t* pinger;
+
+  pinger = (pinger_t*)handle->data;
+  fprintf(stderr, "ping_pongs: %d roundtrips/s\n", (1000 * pinger->pongs) / TIME);
+  fflush(stderr);
+
+  free(pinger);
+
+  completed_pingers++;
+}
+
+
+static void pinger_write_cb(uv_write_t* req, int status) {
+  ASSERT_OK(status);
+
+  free(req);
+}
+
+
+static void pinger_write_ping(pinger_t* pinger) {
+  uv_write_t* req;
+  uv_buf_t buf;
+
+  buf = uv_buf_init(PING, sizeof(PING) - 1);
+
+  req = malloc(sizeof *req);
+  if (uv_write(req, (uv_stream_t*) &pinger->tcp, &buf, 1, pinger_write_cb)) {
+    FATAL("uv_write failed");
+  }
+}
+
+
+static void pinger_shutdown_cb(uv_shutdown_t* req, int status) {
+  ASSERT_OK(status);
+  pinger_shutdown_cb_called++;
+
+  /*
+   * The close callback has not been triggered yet. We must wait for EOF
+   * until we close the connection.
+   */
+  ASSERT_OK(completed_pingers);
+}
+
+
+static void pinger_read_cb(uv_stream_t* tcp,
+                           ssize_t nread,
+                           const uv_buf_t* buf) {
+  ssize_t i;
+  pinger_t* pinger;
+
+  pinger = (pinger_t*)tcp->data;
+
+  if (nread < 0) {
+    ASSERT_EQ(nread, UV_EOF);
+
+    if (buf->base) {
+      buf_free(buf);
+    }
+
+    ASSERT_EQ(1, pinger_shutdown_cb_called);
+    uv_close((uv_handle_t*)tcp, pinger_close_cb);
+
+    return;
+  }
+
+  /* Now we count the pings */
+  for (i = 0; i < nread; i++) {
+    ASSERT_EQ(buf->base[i], PING[pinger->state]);
+    pinger->state = (pinger->state + 1) % (sizeof(PING) - 1);
+    if (pinger->state == 0) {
+      pinger->pongs++;
+      if (uv_now(loop) - start_time > TIME) {
+        uv_shutdown(&pinger->shutdown_req,
+                    (uv_stream_t*) tcp,
+                    pinger_shutdown_cb);
+        break;
+      } else {
+        pinger_write_ping(pinger);
+      }
+    }
+  }
+
+  buf_free(buf);
+}
+
+
+static void pinger_connect_cb(uv_connect_t* req, int status) {
+  pinger_t *pinger = (pinger_t*)req->handle->data;
+
+  ASSERT_OK(status);
+
+  pinger_write_ping(pinger);
+
+  if (uv_read_start(req->handle, buf_alloc, pinger_read_cb)) {
+    FATAL("uv_read_start failed");
+  }
+}
+
+
+static void pinger_new(void) {
+  struct sockaddr_in client_addr;
+  struct sockaddr_in server_addr;
+  pinger_t *pinger;
+  int r;
+
+  ASSERT_OK(uv_ip4_addr("0.0.0.0", 0, &client_addr));
+  ASSERT_OK(uv_ip4_addr("127.0.0.1", TEST_PORT, &server_addr));
+  pinger = malloc(sizeof(*pinger));
+  pinger->state = 0;
+  pinger->pongs = 0;
+
+  /* Try to connect to the server and do NUM_PINGS ping-pongs. */
+  r = uv_tcp_init(loop, &pinger->tcp);
+  ASSERT(!r);
+
+  pinger->tcp.data = pinger;
+
+  ASSERT_OK(uv_tcp_bind(&pinger->tcp,
+                        (const struct sockaddr*) &client_addr,
+                        0));
+
+  r = uv_tcp_connect(&pinger->connect_req,
+                     &pinger->tcp,
+                     (const struct sockaddr*) &server_addr,
+                     pinger_connect_cb);
+  ASSERT(!r);
+}
+
+
+BENCHMARK_IMPL(ping_pongs) {
+  loop = uv_default_loop();
+
+  start_time = uv_now(loop);
+
+  pinger_new();
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_EQ(1, completed_pingers);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}