DataSource.h revision 771b85d9245a24273497792a2515d88d31c99e1e
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/KeyedVector.h> 25#include <utils/List.h> 26#include <utils/RefBase.h> 27#include <utils/threads.h> 28#include <drm/DrmManagerClient.h> 29 30namespace android { 31 32struct AMessage; 33class String8; 34 35class DataSource : public RefBase { 36public: 37 enum Flags { 38 kWantsPrefetching = 1, 39 kStreamedFromLocalHost = 2, 40 kIsCachingDataSource = 4, 41 }; 42 43 static sp<DataSource> CreateFromURI( 44 const char *uri, 45 const KeyedVector<String8, String8> *headers = NULL); 46 47 DataSource() {} 48 49 virtual status_t initCheck() const = 0; 50 51 virtual ssize_t readAt(off_t offset, void *data, size_t size) = 0; 52 53 // Convenience methods: 54 bool getUInt16(off_t offset, uint16_t *x); 55 56 // May return ERROR_UNSUPPORTED. 57 virtual status_t getSize(off_t *size); 58 59 virtual uint32_t flags() { 60 return 0; 61 } 62 63 //////////////////////////////////////////////////////////////////////////// 64 65 bool sniff(String8 *mimeType, float *confidence, sp<AMessage> *meta); 66 67 // The sniffer can optionally fill in "meta" with an AMessage containing 68 // a dictionary of values that helps the corresponding extractor initialize 69 // its state without duplicating effort already exerted by the sniffer. 70 typedef bool (*SnifferFunc)( 71 const sp<DataSource> &source, String8 *mimeType, 72 float *confidence, sp<AMessage> *meta); 73 74 static void RegisterSniffer(SnifferFunc func); 75 static void RegisterDefaultSniffers(); 76 77 // for DRM 78 virtual DecryptHandle* DrmInitialization(DrmManagerClient *client) { 79 return NULL; 80 } 81 virtual void getDrmInfo(DecryptHandle **handle, DrmManagerClient **client) {}; 82 83 virtual String8 getUri() { 84 return String8(); 85 } 86 87protected: 88 virtual ~DataSource() {} 89 90private: 91 static Mutex gSnifferMutex; 92 static List<SnifferFunc> gSniffers; 93 94 DataSource(const DataSource &); 95 DataSource &operator=(const DataSource &); 96}; 97 98} // namespace android 99 100#endif // DATA_SOURCE_H_ 101