Add utility classes (Slice, Fd, Status, etc)
Test: as follows
- built
- flashed
- bootedt log
- netdutils_test passes
- unsubmitted NFLogListenerTest passes
Bug: 28806131
Change-Id: I17846a0dee1edca55df10e5464e607109d978cb5
diff --git a/libnetdutils/include/netdutils/Misc.h b/libnetdutils/include/netdutils/Misc.h
new file mode 100644
index 0000000..41f5778
--- /dev/null
+++ b/libnetdutils/include/netdutils/Misc.h
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef NETUTILS_MISC_H
+#define NETUTILS_MISC_H
+
+#include <map>
+
+namespace android {
+namespace netdutils {
+
+// Lookup key in map, returing a default value if key is not found
+template <typename U, typename V>
+inline const V& findWithDefault(const std::map<U, V>& map, const U& key, const V& dflt) {
+ auto it = map.find(key);
+ return (it == map.end()) ? dflt : it->second;
+}
+
+// Movable, copiable, scoped lambda (or std::function) runner. Useful
+// for running arbitrary cleanup or logging code when exiting a scope.
+//
+// Compare to defer in golang.
+template <typename FnT>
+class Cleanup {
+ public:
+ Cleanup() = delete;
+ Cleanup(FnT fn) : mFn(fn) {}
+ ~Cleanup() { mFn(); }
+
+ void release() { mFn = {}; }
+
+ private:
+ FnT mFn;
+};
+
+// Helper to make a new Cleanup. Avoids complex or impossible syntax
+// when wrapping lambdas.
+//
+// Usage:
+// auto cleanup = makeCleanup([](){ your_code_here; });
+template <typename FnT>
+Cleanup<FnT> makeCleanup(FnT fn) {
+ return Cleanup<FnT>(fn);
+}
+
+} // namespace netdutils
+} // namespace android
+
+#endif /* NETUTILS_MISC_H */