test: add 'unexpected read' tcp test

Regression test that verifies that the event loop doesn't busy loop when
the server sends a message and the client isn't reading.

test/test-list.h

@@ -56,6 +56,7 @@ TEST_DECLARE   (tcp_close)
 TEST_DECLARE   (tcp_flags)
 TEST_DECLARE   (tcp_write_error)
 TEST_DECLARE   (tcp_write_to_half_open_connection)
+TEST_DECLARE   (tcp_unexpected_read)
 TEST_DECLARE   (tcp_bind6_error_addrinuse)
 TEST_DECLARE   (tcp_bind6_error_addrnotavail)
 TEST_DECLARE   (tcp_bind6_error_fault)
@@ -251,6 +252,7 @@ TASK_LIST_START
   TEST_ENTRY  (tcp_flags)
   TEST_ENTRY  (tcp_write_error)
   TEST_ENTRY  (tcp_write_to_half_open_connection)
+  TEST_ENTRY  (tcp_unexpected_read)
 
   TEST_ENTRY  (tcp_bind6_error_addrinuse)
   TEST_ENTRY  (tcp_bind6_error_addrnotavail)

test/test-tcp-unexpected-read.c

@@ -0,0 +1,111 @@
+/* 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"
+
+static uv_check_t check_handle;
+static uv_timer_t timer_handle;
+static uv_tcp_t server_handle;
+static uv_tcp_t client_handle;
+static uv_tcp_t peer_handle;
+static uv_write_t write_req;
+static uv_connect_t connect_req;
+
+static unsigned long ticks; /* event loop ticks */
+
+
+static void check_cb(uv_check_t* handle, int status) {
+  ticks++;
+}
+
+
+static void timer_cb(uv_timer_t* handle, int status) {
+  uv_close((uv_handle_t*) &check_handle, NULL);
+  uv_close((uv_handle_t*) &timer_handle, NULL);
+  uv_close((uv_handle_t*) &server_handle, NULL);
+  uv_close((uv_handle_t*) &client_handle, NULL);
+  uv_close((uv_handle_t*) &peer_handle, NULL);
+}
+
+
+static uv_buf_t alloc_cb(uv_handle_t* handle, size_t suggested_size) {
+  ASSERT(0 && "alloc_cb should not have been called");
+}
+
+
+static void read_cb(uv_stream_t* handle, ssize_t nread, uv_buf_t buf) {
+  ASSERT(0 && "read_cb should not have been called");
+}
+
+
+static void connect_cb(uv_connect_t* req, int status) {
+  ASSERT(req->handle == (uv_stream_t*) &client_handle);
+  ASSERT(0 == status);
+}
+
+
+static void write_cb(uv_write_t* req, int status) {
+  ASSERT(req->handle == (uv_stream_t*) &peer_handle);
+  ASSERT(0 == status);
+}
+
+
+static void connection_cb(uv_stream_t* handle, int status) {
+  uv_buf_t buf;
+
+  buf = uv_buf_init("PING", 4);
+
+  ASSERT(0 == status);
+  ASSERT(0 == uv_tcp_init(uv_default_loop(), &peer_handle));
+  ASSERT(0 == uv_accept(handle, (uv_stream_t*) &peer_handle));
+  ASSERT(0 == uv_read_start((uv_stream_t*) &peer_handle, alloc_cb, read_cb));
+  ASSERT(0 == uv_write(&write_req, (uv_stream_t*) &peer_handle,
+                       &buf, 1, write_cb));
+}
+
+
+TEST_IMPL(tcp_unexpected_read) {
+  struct sockaddr_in addr;
+  uv_loop_t* loop;
+
+  addr = uv_ip4_addr("127.0.0.1", TEST_PORT);
+  loop = uv_default_loop();
+
+  ASSERT(0 == uv_timer_init(loop, &timer_handle));
+  ASSERT(0 == uv_timer_start(&timer_handle, timer_cb, 1000, 0));
+  ASSERT(0 == uv_check_init(loop, &check_handle));
+  ASSERT(0 == uv_check_start(&check_handle, check_cb));
+  ASSERT(0 == uv_tcp_init(loop, &server_handle));
+  ASSERT(0 == uv_tcp_init(loop, &client_handle));
+  ASSERT(0 == uv_tcp_bind(&server_handle, addr));
+  ASSERT(0 == uv_listen((uv_stream_t*) &server_handle, 1, connection_cb));
+  ASSERT(0 == uv_tcp_connect(&connect_req, &client_handle, addr, connect_cb));
+  ASSERT(0 == uv_run(loop));
+
+  /* This is somewhat inexact but the idea is that the event loop should not
+   * start busy looping when the server sends a message and the client isn't
+   * reading.
+   */
+  ASSERT(ticks <= 10);
+
+  return 0;
+}

uv.gyp

@@ -355,6 +355,7 @@
         'test/test-tcp-write-error.c',
         'test/test-tcp-write-to-half-open-connection.c',
         'test/test-tcp-writealot.c',
+        'test/test-tcp-unexpected-read.c',
         'test/test-threadpool.c',
         'test/test-mutexes.c',
         'test/test-thread.c',