1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef ANDROID_UTILS_FLATTENABLE_H 18 #define ANDROID_UTILS_FLATTENABLE_H 19 20 21 #include <stdint.h> 22 #include <sys/types.h> 23 #include <utils/Errors.h> 24 25 namespace android { 26 27 class Flattenable 28 { 29 public: 30 // size in bytes of the flattened object 31 virtual size_t getFlattenedSize() const = 0; 32 33 // number of file descriptors to flatten 34 virtual size_t getFdCount() const = 0; 35 36 // flattens the object into buffer. 37 // size should be at least of getFlattenedSize() 38 // file descriptors are written in the fds[] array but ownership is 39 // not transfered (ie: they must be dupped by the caller of 40 // flatten() if needed). 41 virtual status_t flatten(void* buffer, size_t size, 42 int fds[], size_t count) const = 0; 43 44 // unflattens the object from buffer. 45 // size should be equal to the value of getFlattenedSize() when the 46 // object was flattened. 47 // unflattened file descriptors are found in the fds[] array and 48 // don't need to be dupped(). ie: the caller of unflatten doesn't 49 // keep ownership. If a fd is not retained by unflatten() it must be 50 // explicitly closed. 51 virtual status_t unflatten(void const* buffer, size_t size, 52 int fds[], size_t count) = 0; 53 54 protected: 55 virtual ~Flattenable() = 0; 56 57 }; 58 59 }; // namespace android 60 61 62 #endif /* ANDROID_UTILS_FLATTENABLE_H */ 63