import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

xpcom/base/LogModulePrefWatcher.h

@@ -0,0 +1,42 @@
+/* -*- 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/. */
+
+#ifndef LogModulePrefWatcher_h
+#define LogModulePrefWatcher_h
+
+#include "nsIObserver.h"
+
+namespace mozilla {
+
+/**
+ * Watches for changes to "logging.*" prefs and then updates the appropriate
+ * LogModule's log level. Both the integer and string versions of the LogLevel
+ * enum are supported.
+ *
+ * For example setting the pref "logging.Foo" to "Verbose" will set the
+ * LogModule for "Foo" to the LogLevel::Verbose level. Setting "logging.Bar" to
+ * 4 would set the LogModule for "Bar" to the LogLevel::Debug level.
+ */
+class LogModulePrefWatcher : public nsIObserver
+{
+public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIOBSERVER
+
+  /**
+   * Starts observing logging pref changes.
+   */
+  static void RegisterPrefWatcher();
+
+private:
+  LogModulePrefWatcher();
+  virtual ~LogModulePrefWatcher()
+  {
+  }
+};
+} // namespace mozilla
+
+#endif // LogModulePrefWatcher_h