base: add a unit test for SetCloseOnExec() function

base/files/file_util_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
 #include <fstream>
 #include <initializer_list>
@@ skipping 2249 matching lines @@
   EXPECT_FALSE(SetNonBlocking(kInvalidFd));
 
   base::FilePath path;
   ASSERT_TRUE(PathService::Get(base::DIR_TEST_DATA, &path));
   path = path.Append(FPL("file_util")).Append(FPL("original.txt"));
   ScopedFD fd(open(path.value().c_str(), O_RDONLY));
   ASSERT_GE(fd.get(), 0);
   EXPECT_TRUE(SetNonBlocking(fd.get()));
 }
 
+TEST_F(FileUtilTest, SetCloseOnExec) {
+  const int kInvalidFd = 99999;
+  EXPECT_FALSE(SetCloseOnExec(kInvalidFd));
+
+  base::FilePath path;
+  ASSERT_TRUE(PathService::Get(base::DIR_TEST_DATA, &path));
+  path = path.Append(FPL("file_util")).Append(FPL("original.txt"));
+  ScopedFD fd(open(path.value().c_str(), O_RDONLY));
+  ASSERT_GE(fd.get(), 0);
+  EXPECT_TRUE(SetCloseOnExec(fd.get()));
+}
+
 // Testing VerifyPathControlledByAdmin() is hard, because there is no
 // way a test can make a file owned by root, or change file paths
 // at the root of the file system.  VerifyPathControlledByAdmin()
 // is implemented as a call to VerifyPathControlledByUser, which gives
 // us the ability to test with paths under the test's temp directory,
 // using a user id we control.
 // Pull tests of VerifyPathControlledByUserTest() into a separate test class
 // with a common SetUp() method.
 class VerifyPathControlledByUserTest : public FileUtilTest {
  protected:
@@ skipping 349 matching lines @@
   // Trying to close it should crash. This is important for security.
   EXPECT_DEATH(CloseWithScopedFD(fds[1]), "");
 #endif
 }
 
 #endif  // defined(OS_POSIX)
 
 }  // namespace
 
 }  // namespace base