Update from https://crrev.com/306655

sandbox/linux/seccomp-bpf/sandbox_bpf_unittest.cc

+// Copyright 2014 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 "sandbox/linux/seccomp-bpf/sandbox_bpf.h"
+
+#include <fcntl.h>
+#include <unistd.h>
+
+#include <iostream>
+
+#include "base/files/scoped_file.h"
+#include "base/posix/eintr_wrapper.h"
+#include "sandbox/linux/tests/unit_tests.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace sandbox {
+namespace {
+
+// NOTE: most tests for the SandboxBPF class are currently in
+// bpf_dsl_more_unittest.cc.
+
+TEST(SandboxBPF, CreateDestroy) {
+  // Give an opportunity to dynamic tools to perform some simple testing.
+  SandboxBPF sandbox(nullptr);
+  SandboxBPF* sandbox_ptr = new SandboxBPF(nullptr);
+  delete sandbox_ptr;
+}
+
+// This test should execute no matter whether we have kernel support. So,
+// we make it a TEST() instead of a BPF_TEST().
+TEST(SandboxBPF, DISABLE_ON_TSAN(CallSupports)) {
+  // We check that we don't crash, but it's ok if the kernel doesn't
+  // support it.
+  bool seccomp_bpf_supported = SandboxBPF::SupportsSeccompSandbox(
+      SandboxBPF::SeccompLevel::SINGLE_THREADED);
+  bool seccomp_bpf_tsync_supported = SandboxBPF::SupportsSeccompSandbox(
+      SandboxBPF::SeccompLevel::MULTI_THREADED);
+  // We want to log whether or not seccomp BPF is actually supported
+  // since actual test coverage depends on it.
+  std::cout << "Seccomp BPF supported (single thread): "
+            << (seccomp_bpf_supported ? "true." : "false.") << "\n";
+  std::cout << "Seccomp BPF supported (multi thread): "
+            << (seccomp_bpf_tsync_supported ? "true." : "false.") << "\n";
+  std::cout << "Pointer size: " << sizeof(void*) << "\n";
+}
+
+SANDBOX_TEST(SandboxBPF, DISABLE_ON_TSAN(CallSupportsTwice)) {
+  bool single1 = SandboxBPF::SupportsSeccompSandbox(
+      SandboxBPF::SeccompLevel::SINGLE_THREADED);
+  bool single2 = SandboxBPF::SupportsSeccompSandbox(
+      SandboxBPF::SeccompLevel::SINGLE_THREADED);
+  ASSERT_EQ(single1, single2);
+  bool multi1 = SandboxBPF::SupportsSeccompSandbox(
+      SandboxBPF::SeccompLevel::MULTI_THREADED);
+  bool multi2 = SandboxBPF::SupportsSeccompSandbox(
+      SandboxBPF::SeccompLevel::MULTI_THREADED);
+  ASSERT_EQ(multi1, multi2);
+
+  // Multi threaded support implies single threaded support.
+  if (multi1) {
+    ASSERT_TRUE(single1);
+  }
+}
+
+TEST(SandboxBPF, ProcTaskFdDescriptorGetsClosed) {
+  int pipe_fds[2];
+  ASSERT_EQ(0, pipe(pipe_fds));
+  base::ScopedFD read_end(pipe_fds[0]);
+  base::ScopedFD write_end(pipe_fds[1]);
+
+  {
+    SandboxBPF sandbox(nullptr);
+    sandbox.SetProcTaskFd(write_end.Pass());
+  }
+
+  ASSERT_EQ(0, fcntl(read_end.get(), F_SETFL, O_NONBLOCK));
+  char c;
+  // Check that the sandbox closed the write_end (read will EOF instead of
+  // returning EWOULDBLOCK).
+  ASSERT_EQ(0, read(read_end.get(), &c, 1));
+}
+
+}  // namespace
+}  // sandbox