test: fix test-ipc tests

A couple of ipc tests failures where undercover by the previous commit.

- In `ipc-heavy-traffic-deadlock-bug`, `uv_shutdown` can fail with
  `UV_ENOTCONN`. Allow it.
- `ipc_closed_handle` was failing consistently on `Centos6` because the
  first large write was completed in just one syscall. Also, there were
  issues with the lifetime of the `uv_write_t` requests. Refactor the
  test so it passes consistently on `Centos6` while fixing the
  `uv_write_t` issues.

PR-URL: https://github.com/libuv/libuv/pull/2108
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

test/test-ipc-heavy-traffic-deadlock-bug.c

@@ -55,7 +55,7 @@ static void write_cb(uv_write_t* req, int status) {
 }
 
 static void shutdown_cb(uv_shutdown_t* req, int status) {
-  ASSERT(status == 0);
+  ASSERT(status == 0 || status == UV_ENOTCONN);
   uv_close((uv_handle_t*) req->handle, NULL);
 }
 

test/test-ipc.c

@@ -39,12 +39,14 @@ static int local_conn_accepted;
 static int remote_conn_accepted;
 static int tcp_server_listening;
 static uv_write_t write_req;
+static uv_write_t write_req2;
 static uv_write_t conn_notify_req;
 static int close_cb_called;
 static int connection_accepted;
 static int tcp_conn_read_cb_called;
 static int tcp_conn_write_cb_called;
 static int closed_handle_data_read;
+static int closed_handle_write;
 
 typedef struct {
   uv_connect_t conn_req;
@@ -54,7 +56,15 @@ typedef struct {
 
 #define CONN_COUNT 100
 #define BACKLOG 128
-#define LARGE_SIZE 1000000
+#define LARGE_SIZE 100000
+
+static uv_buf_t large_buf;
+static char buffer[LARGE_SIZE];
+static uv_write_t write_reqs[300];
+static int write_reqs_completed;
+
+static unsigned int write_until_data_queued(void);
+static void send_handle_and_close(void);
 
 
 static void close_server_conn_cb(uv_handle_t* handle) {
@@ -574,11 +584,17 @@ static void tcp_connection_write_cb(uv_write_t* req, int status) {
 static void closed_handle_large_write_cb(uv_write_t* req, int status) {
   ASSERT(status == 0);
   ASSERT(closed_handle_data_read = LARGE_SIZE);
+  if (++write_reqs_completed == ARRAY_SIZE(write_reqs)) {
+    write_reqs_completed = 0;
+    if (write_until_data_queued() > 0)
+      send_handle_and_close();
+  }
 }
 
 
 static void closed_handle_write_cb(uv_write_t* req, int status) {
   ASSERT(status == UV_EBADF);
+  closed_handle_write = 1;
 }
 
 
@@ -689,7 +705,6 @@ int ipc_helper(int listen_after_write) {
    * over which a handle will be transmitted.
    */
   struct sockaddr_in addr;
-  uv_write_t write_req;
   int r;
   uv_buf_t buf;
 
@@ -789,14 +804,53 @@ int ipc_helper_tcp_connection(void) {
   return 0;
 }
 
+static unsigned int write_until_data_queued() {
+  unsigned int i;
+  int r;
+
+  i = 0;
+  do {
+    r = uv_write(&write_reqs[i],
+                 (uv_stream_t*)&channel,
+                 &large_buf,
+                 1,
+                 closed_handle_large_write_cb);
+    ASSERT(r == 0);
+    i++;
+  } while (((uv_stream_t*)&channel)->write_queue_size == 0 &&
+           i < ARRAY_SIZE(write_reqs));
+
+  return ((uv_stream_t*)&channel)->write_queue_size;
+}
+
+static void send_handle_and_close() {
+  int r;
+  struct sockaddr_in addr;
+
+  r = uv_tcp_init(uv_default_loop(), &tcp_server);
+  ASSERT(r == 0);
+
+  ASSERT(0 == uv_ip4_addr("0.0.0.0", TEST_PORT, &addr));
+
+  r = uv_tcp_bind(&tcp_server, (const struct sockaddr*) &addr, 0);
+  ASSERT(r == 0);
+
+  r = uv_write2(&write_req,
+                (uv_stream_t*)&channel,
+                &large_buf,
+                1,
+                (uv_stream_t*)&tcp_server,
+                closed_handle_write_cb);
+  ASSERT(r == 0);
+
+  uv_close((uv_handle_t*)&tcp_server, NULL);
+}
 
 int ipc_helper_closed_handle(void) {
   int r;
-  struct sockaddr_in addr;
-  uv_write_t write_req;
-  uv_write_t write_req2;
-  uv_buf_t buf;
-  char buffer[LARGE_SIZE];
+
+  memset(buffer, '.', LARGE_SIZE);
+  large_buf = uv_buf_init(buffer, LARGE_SIZE);
 
   r = uv_pipe_init(uv_default_loop(), &channel, 1);
   ASSERT(r == 0);
@@ -807,37 +861,14 @@ int ipc_helper_closed_handle(void) {
   ASSERT(1 == uv_is_writable((uv_stream_t*) &channel));
   ASSERT(0 == uv_is_closing((uv_handle_t*) &channel));
 
-  memset(buffer, '.', LARGE_SIZE);
-  buf = uv_buf_init(buffer, LARGE_SIZE);
-
-  r = uv_tcp_init(uv_default_loop(), &tcp_server);
-  ASSERT(r == 0);
-
-  ASSERT(0 == uv_ip4_addr("0.0.0.0", TEST_PORT, &addr));
-
-  r = uv_tcp_bind(&tcp_server, (const struct sockaddr*) &addr, 0);
-  ASSERT(r == 0);
-
-  r = uv_write(&write_req,
-               (uv_stream_t*)&channel,
-               &buf,
-               1,
-               closed_handle_large_write_cb);
-  ASSERT(r == 0);
-
-  r = uv_write2(&write_req2,
-                (uv_stream_t*)&channel,
-                &buf,
-                1,
-                (uv_stream_t*)&tcp_server,
-                closed_handle_write_cb);
-  ASSERT(r == 0);
-
-  uv_close((uv_handle_t*)&tcp_server, NULL);
+  if (write_until_data_queued() > 0)
+    send_handle_and_close();
 
   r = uv_run(uv_default_loop(), UV_RUN_DEFAULT);
   ASSERT(r == 0);
 
+  ASSERT(closed_handle_write == 1);
+
   MAKE_VALGRIND_HAPPY();
   return 0;
 }
@@ -849,8 +880,6 @@ int ipc_helper_bind_twice(void) {
    * over which two handles will be transmitted.
    */
   struct sockaddr_in addr;
-  uv_write_t write_req;
-  uv_write_t write_req2;
   int r;
   uv_buf_t buf;