Simplified unit testing of sandboxing code.

sandbox/linux/seccomp-bpf/bpf_tests.h

+// 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.
+
+#ifndef SANDBOX_LINUX_SECCOMP_BPF_BPF_TESTS_H__
+#define SANDBOX_LINUX_SECCOMP_BPF_BPF_TESTS_H__
+
+#include "sandbox/linux/tests/unit_tests.h"
+#include "sandbox/linux/seccomp-bpf/sandbox_bpf.h"
+
+
+namespace sandbox {
+
+// BPF_TEST() is a special version of SANDBOX_TEST(). It turns into a no-op,
+// if the host does not have kernel support for running BPF filters.
+// Also, it takes advantage of the Die class to avoid calling LOG(FATAL), from
+// inside our tests, as we don't need or even want all the error handling that
+// LOG(FATAL) would do.
+#define BPF_TEST(test_case_name, test_name, policy)                           \
+  void BPF_TEST_##test_name();                                                \
+  void BPF_TEST_##test_name##_wrapper() {                                     \
+    Die::EnableSimpleExit();                                                  \
+    if (reinterpret_cast<void *>(policy) != NULL) {                           \
+      Sandbox::setSandboxPolicy(policy, NULL);                                \
+    }                                                                         \
+    BPF_TEST_##test_name();                                                   \
+  }                                                                           \
+  TEST(test_case_name, test_name) {                                           \
+    if (playground2::Sandbox::supportsSeccompSandbox(-1) ==                   \
+        Sandbox::STATUS_AVAILABLE) {                                          \
+      sandbox::BpfTests::RunTestInProcess(BPF_TEST_##test_name##_wrapper);    \
+    } else {                                                                  \
+      /* TODO(markus): Call the compiler and verify the policy. That's the */ \

[jln (very slow on Chromium), 2012/08/24 04:00:32]

I'm sorry I wasn't clear: I meant to call setSandboxPolicy() in the else branch
here.

The current re-order (calling setSandboxPolicy first) isn't great, most notably
because that's not what will happen in real code.

Also, I agree with you that having to pass policy here is an issue. I'll try to
address this later.

+      /*               least we can do, if we don't have kernel support.   */ \
+    }                                                                         \
+  }                                                                           \
+  void BPF_TEST_##test_name()
+
+// Assertions are handled exactly the same as with a normal SANDBOX_TEST()
+#define BPF_ASSERT SANDBOX_ASSERT
+
+
+class BpfTests : public UnitTests {
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(BpfTests);
+};
+
+}  // namespace
+
+#endif  // SANDBOX_LINUX_SECCOMP_BPF_BPF_TESTS_H__