1 /* 2 * Copyright (C) 2009 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 DATA_SOURCE_H_ 18 19 #define DATA_SOURCE_H_ 20 21 #include <sys/types.h> 22 23 #include <utils/Errors.h> 24 #include <utils/List.h> 25 #include <utils/RefBase.h> 26 #include <utils/threads.h> 27 28 namespace android { 29 30 class String8; 31 32 class DataSource : public RefBase { 33 public: DataSource()34 DataSource() {} 35 36 virtual ssize_t read_at(off_t offset, void *data, size_t size) = 0; 37 38 // Convenience methods: 39 bool getUInt16(off_t offset, uint16_t *x); 40 41 // May return ERROR_UNSUPPORTED. 42 virtual status_t getSize(off_t *size); 43 44 //////////////////////////////////////////////////////////////////////////// 45 46 bool sniff(String8 *mimeType, float *confidence); 47 48 typedef bool (*SnifferFunc)( 49 const sp<DataSource> &source, String8 *mimeType, float *confidence); 50 51 static void RegisterSniffer(SnifferFunc func); 52 static void RegisterDefaultSniffers(); 53 54 protected: ~DataSource()55 virtual ~DataSource() {} 56 57 private: 58 static Mutex gSnifferMutex; 59 static List<SnifferFunc> gSniffers; 60 61 DataSource(const DataSource &); 62 DataSource &operator=(const DataSource &); 63 }; 64 65 } // namespace android 66 67 #endif // DATA_SOURCE_H_ 68