Add NativeHandle, a refcounted C++ wrapper around a native_handle_t*

Change-Id: I232dfa2ad2e4a463a39e2e901e4097dffe278cc3

include/utils/NativeHandle.h

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2014 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 ANDROID_NATIVE_HANDLE_H
+#define ANDROID_NATIVE_HANDLE_H
+
+#include <utils/RefBase.h>
+#include <utils/StrongPointer.h>
+
+typedef struct native_handle native_handle_t;
+
+namespace android {
+
+class NativeHandle: public LightRefBase<NativeHandle> {
+public:
+    // Create a refcounted wrapper around a native_handle_t.
+    // If handle is NULL, no NativeHandle will be created.
+    static sp<NativeHandle> create(native_handle_t* handle);
+
+    const native_handle_t* handle() const {
+        return mHandle;
+    }
+
+private:
+    // for access to the destructor
+    friend class LightRefBase<NativeHandle>;
+
+    NativeHandle(native_handle_t* handle);
+    virtual ~NativeHandle();
+
+    native_handle_t* mHandle;
+
+    // non-copyable
+    NativeHandle(const NativeHandle&);
+    NativeHandle& operator=(const NativeHandle&);
+};
+
+} // namespace android
+
+#endif // ANDROID_NATIVE_HANDLE_H

libutils/Android.mk

@@ -26,6 +26,7 @@ commonSources:= \
 	LinearAllocator.cpp \
 	LinearTransform.cpp \
 	Log.cpp \
+	NativeHandle.cpp \
 	Printer.cpp \
 	ProcessCallStack.cpp \
 	PropertyMap.cpp \

libutils/NativeHandle.cpp

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2014 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.
+ */
+
+#include <utils/NativeHandle.h>
+#include <cutils/native_handle.h>
+
+namespace android {
+
+sp<NativeHandle> NativeHandle::create(native_handle_t* handle) {
+    return handle ? new NativeHandle(handle) : NULL;
+}
+
+NativeHandle::NativeHandle(native_handle_t* handle)
+:   mHandle(handle)
+{}
+
+NativeHandle::~NativeHandle() {
+    native_handle_close(mHandle);
+    native_handle_delete(mHandle);
+}
+
+} // namespace android