diff --git a/cmds/lshal/NullableOStream.h b/cmds/lshal/NullableOStream.h
new file mode 100644
index 0000000..ab37a04
--- /dev/null
+++ b/cmds/lshal/NullableOStream.h
@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2016 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 FRAMEWORK_NATIVE_CMDS_LSHAL_NULLABLE_O_STREAM_H_
+#define FRAMEWORK_NATIVE_CMDS_LSHAL_NULLABLE_O_STREAM_H_
+
+#include <iostream>
+
+namespace android {
+namespace lshal {
+
+template<typename S>
+class NullableOStream {
+public:
+    NullableOStream(S &os) : mOs(&os) {}
+    NullableOStream(S *os) : mOs(os) {}
+    NullableOStream &operator=(S &os) {
+        mOs = &os;
+        return *this;
+    }
+    NullableOStream &operator=(S *os) {
+        mOs = os;
+        return *this;
+    }
+    template<typename Other>
+    NullableOStream &operator=(const NullableOStream<Other> &other) {
+        mOs = other.mOs;
+        return *this;
+    }
+
+    const NullableOStream &operator<<(std::ostream& (*pf)(std::ostream&)) const {
+        if (mOs) {
+            (*mOs) << pf;
+        }
+        return *this;
+    }
+    template<typename T>
+    const NullableOStream &operator<<(const T &rhs) const {
+        if (mOs) {
+            (*mOs) << rhs;
+        }
+        return *this;
+    }
+    S& buf() const {
+        return *mOs;
+    }
+    operator bool() const {
+        return mOs != nullptr;
+    }
+private:
+    template<typename>
+    friend class NullableOStream;
+
+    S *mOs = nullptr;
+};
+
+}  // namespace lshal
+}  // namespace android
+
+#endif  // FRAMEWORK_NATIVE_CMDS_LSHAL_NULLABLE_O_STREAM_H_