michael@0: /*
michael@0:  * Copyright (C) 2010 The Android Open Source Project
michael@0:  *
michael@0:  * Licensed under the Apache License, Version 2.0 (the "License");
michael@0:  * you may not use this file except in compliance with the License.
michael@0:  * You may obtain a copy of the License at
michael@0:  *
michael@0:  *      http://www.apache.org/licenses/LICENSE-2.0
michael@0:  *
michael@0:  * Unless required by applicable law or agreed to in writing, software
michael@0:  * distributed under the License is distributed on an "AS IS" BASIS,
michael@0:  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
michael@0:  * See the License for the specific language governing permissions and
michael@0:  * limitations under the License.
michael@0:  */
michael@0: 
michael@0: #ifndef ANDROID_UTILS_FLATTENABLE_H
michael@0: #define ANDROID_UTILS_FLATTENABLE_H
michael@0: 
michael@0: 
michael@0: #include <stdint.h>
michael@0: #include <sys/types.h>
michael@0: #include <utils/Errors.h>
michael@0: 
michael@0: namespace android {
michael@0: 
michael@0: class Flattenable
michael@0: {
michael@0: public:
michael@0:     // size in bytes of the flattened object
michael@0:     virtual size_t getFlattenedSize() const = 0;
michael@0: 
michael@0:     // number of file descriptors to flatten
michael@0:     virtual size_t getFdCount() const = 0;
michael@0: 
michael@0:     // flattens the object into buffer.
michael@0:     // size should be at least of getFlattenedSize()
michael@0:     // file descriptors are written in the fds[] array but ownership is
michael@0:     // not transfered (ie: they must be dupped by the caller of
michael@0:     // flatten() if needed).
michael@0:     virtual status_t flatten(void* buffer, size_t size,
michael@0:             int fds[], size_t count) const = 0;
michael@0: 
michael@0:     // unflattens the object from buffer.
michael@0:     // size should be equal to the value of getFlattenedSize() when the
michael@0:     // object was flattened.
michael@0:     // unflattened file descriptors are found in the fds[] array and
michael@0:     // don't need to be dupped(). ie: the caller of unflatten doesn't
michael@0:     // keep ownership. If a fd is not retained by unflatten() it must be
michael@0:     // explicitly closed.
michael@0:     virtual status_t unflatten(void const* buffer, size_t size,
michael@0:             int fds[], size_t count) = 0;
michael@0: 
michael@0: protected:
michael@0:     virtual ~Flattenable() = 0;
michael@0: 
michael@0: };
michael@0: 
michael@0: }; // namespace android
michael@0: 
michael@0: 
michael@0: #endif /* ANDROID_UTILS_FLATTENABLE_H */