Linux Sandbox: add resource limits to NaCl

sandbox/linux/services/resource_limits.h

+// Copyright 2015 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_SERVICES_RESOURCE_LIMITS_H_
+#define SANDBOX_LINUX_SERVICES_RESOURCE_LIMITS_H_
+
+#include <sys/resource.h>
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/macros.h"
+#include "sandbox/sandbox_export.h"
+
+namespace sandbox {
+
+// This class provides a small wrapper around setrlimit().
+class SANDBOX_EXPORT ResourceLimits {

[Mark Seaborn, 2015/02/13 17:11:54]

Aside: In my opinion, using a class that will never be instantiated as a
namespace is a slightly odd style.  But I suppose this is a common style in
sandbox/?

[jln (very slow on Chromium), 2015/02/13 18:00:05]

I think it's even the prevailing style in all of Chromium. base/ is definitely
the same and I see this all over the place. It's rare to see namespaces used
with file scopes.

Moreover "exporting" is much more concise with classes.

+ public:
+  // Lower the soft and hard limit of |resource| to |limit|. If the current
+  // limit is lower than |limit|, keep it.
+  static bool Lower(int resource, rlim_t limit) WARN_UNUSED_RESULT;
+
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(ResourceLimits);
+};
+
+}  // namespace sandbox
+
+#endif  // SANDBOX_LINUX_SERVICES_RESOURCE_LIMITS_H_