1 files changed, 55 insertions, 0 deletions
diff --git a/test/syscalls/linux/fsync.cc b/test/syscalls/linux/fsync.cc
new file mode 100644
index 000000000..536a73bf1
--- /dev/null
+++ b/test/syscalls/linux/fsync.cc
@@ -0,0 +1,55 @@
+// Copyright 2018 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.
+
+#include <fcntl.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include <string>
+
+#include "gtest/gtest.h"
+#include "test/util/temp_path.h"
+#include "test/util/test_util.h"
+
+namespace gvisor {
+namespace testing {
+
+namespace {
+
+TEST(FsyncTest, TempFileSucceeds) {
+  std::string path = NewTempAbsPath();
+  int fd;
+  EXPECT_THAT(fd = open(path.c_str(), O_RDWR | O_CREAT, 0666),
+              SyscallSucceeds());
+  const std::string data = "some data to sync";
+  EXPECT_THAT(write(fd, data.c_str(), data.size()),
+              SyscallSucceedsWithValue(data.size()));
+  EXPECT_THAT(fsync(fd), SyscallSucceeds());
+  ASSERT_THAT(close(fd), SyscallSucceeds());
+  ASSERT_THAT(unlink(path.c_str()), SyscallSucceeds());
+}
+
+TEST(FsyncTest, CannotFsyncOnUnopenedFd) {
+  int fd;
+  auto f = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile());
+  ASSERT_THAT(fd = open(f.path().c_str(), O_RDONLY), SyscallSucceeds());
+  ASSERT_THAT(close(fd), SyscallSucceeds());
+
+  // fd is now invalid.
+  EXPECT_THAT(fsync(fd), SyscallFailsWithErrno(EBADF));
+}
+}  // namespace
+
+}  // namespace testing
+}  // namespace gvisor