import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

security/sandbox/linux/gtest/TestSandboxUtil.cpp

@@ -0,0 +1,44 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "gtest/gtest.h"
+
+#include "SandboxUtil.h"
+#include "SandboxInfo.h"
+
+#include <pthread.h>
+
+namespace mozilla {
+
+// In order to test IsSingleThreaded when the test-running process is
+// single-threaded, before assorted XPCOM components have created many
+// additional threads, a static initializer is used.
+
+namespace {
+
+struct EarlyTest {
+  bool mWasSingleThreaded;
+
+  EarlyTest()
+  : mWasSingleThreaded(IsSingleThreaded())
+  { }
+};
+
+static const EarlyTest gEarlyTest;
+
+} // namespace
+
+TEST(SandboxUtil, IsSingleThreaded)
+{
+  // If the test system if affected by kUnexpectedThreads, (1) there's
+  // no point in doing this test, and (2) if that happens on Mozilla
+  // CI then burning the tree is an appropriate response.
+  ASSERT_FALSE(SandboxInfo::Get().Test(SandboxInfo::kUnexpectedThreads));
+  EXPECT_TRUE(gEarlyTest.mWasSingleThreaded);
+  EXPECT_FALSE(IsSingleThreaded());
+}
+
+} // namespace mozilla