Refactor out NewEventFD to a test utility.

PiperOrigin-RevId: 231404512
Change-Id: I31efcc23a0c4a48ef6fbba3ca07415d79290f55c

2 files changed, 54 insertions, 0 deletions

diff --git a/test/util/BUILD b/test/util/BUILD
index 6316fec6e..f2e563507 100644
--- a/test/util/BUILD
+++ b/test/util/BUILD
@@ -19,6 +19,17 @@ cc_library(
 )
 
 cc_library(
+    name = "eventfd_util",
+    testonly = 1,
+    hdrs = ["eventfd_util.h"],
+    deps = [
+        ":file_descriptor",
+        ":posix_error",
+        ":save_util",
+    ],
+)
+
+cc_library(
     name = "file_descriptor",
     testonly = 1,
     hdrs = ["file_descriptor.h"],
diff --git a/test/util/eventfd_util.h b/test/util/eventfd_util.h
new file mode 100644
index 000000000..1fdb07d3b
--- /dev/null
+++ b/test/util/eventfd_util.h
@@ -0,0 +1,43 @@
+// Copyright 2019 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef GVISOR_TEST_UTIL_EVENTFD_UTIL_H_
+#define GVISOR_TEST_UTIL_EVENTFD_UTIL_H_
+
+#include <sys/eventfd.h>
+
+#include <cerrno>
+
+#include "test/util/file_descriptor.h"
+#include "test/util/posix_error.h"
+#include "test/util/save_util.h"
+
+namespace gvisor {
+namespace testing {
+
+// Returns a new eventfd with the given initial value and flags.
+inline PosixErrorOr<FileDescriptor> NewEventFD(unsigned int initval = 0,
+                                               int flags = 0) {
+  int fd = eventfd(initval, flags);
+  MaybeSave();
+  if (fd < 0) {
+    return PosixError(errno, "eventfd");
+  }
+  return FileDescriptor(fd);
+}
+
+}  // namespace testing
+}  // namespace gvisor
+
+#endif  // GVISOR_TEST_UTIL_EVENTFD_UTIL_H_