1 /* 2 * Copyright (C) 2016 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 INCLUDE_DATA_SOURCE_H_ 18 #define INCLUDE_DATA_SOURCE_H_ 19 20 #include <jni.h> 21 #include <sys/types.h> 22 23 class DataSource { 24 public: ~DataSource()25 virtual ~DataSource() {} 26 // Returns the number of bytes read, or -1 on failure. It's not an error if 27 // this returns zero; it just means the given offset is equal to, or 28 // beyond, the end of the source. 29 virtual ssize_t readAt(off64_t offset, void* const data, size_t size) = 0; 30 }; 31 32 #endif // INCLUDE_DATA_SOURCE_H_ 33