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 <media/stagefright/MediaErrors.h>
24 #include <utils/Errors.h>
25 #include <utils/KeyedVector.h>
26 #include <utils/List.h>
27 #include <utils/RefBase.h>
28 #include <utils/threads.h>
29 #include <drm/DrmManagerClient.h>
30 
31 namespace android {
32 
33 struct AMessage;
34 struct AString;
35 class  IDataSource;
36 struct IMediaHTTPService;
37 class String8;
38 struct HTTPBase;
39 
40 class DataSource : public RefBase {
41 public:
42     enum Flags {
43         kWantsPrefetching      = 1,
44         kStreamedFromLocalHost = 2,
45         kIsCachingDataSource   = 4,
46         kIsHTTPBasedSource     = 8,
47     };
48 
49     static sp<DataSource> CreateFromURI(
50             const sp<IMediaHTTPService> &httpService,
51             const char *uri,
52             const KeyedVector<String8, String8> *headers = NULL,
53             String8 *contentType = NULL,
54             HTTPBase *httpSource = NULL);
55 
56     static sp<DataSource> CreateMediaHTTP(const sp<IMediaHTTPService> &httpService);
57     static sp<DataSource> CreateFromIDataSource(const sp<IDataSource> &source);
58 
DataSource()59     DataSource() {}
60 
61     virtual status_t initCheck() const = 0;
62 
63     // Returns the number of bytes read, or -1 on failure. It's not an error if
64     // this returns zero; it just means the given offset is equal to, or
65     // beyond, the end of the source.
66     virtual ssize_t readAt(off64_t offset, void *data, size_t size) = 0;
67 
68     // Convenience methods:
69     bool getUInt16(off64_t offset, uint16_t *x);
70     bool getUInt24(off64_t offset, uint32_t *x); // 3 byte int, returned as a 32-bit int
71     bool getUInt32(off64_t offset, uint32_t *x);
72     bool getUInt64(off64_t offset, uint64_t *x);
73 
74     // May return ERROR_UNSUPPORTED.
75     virtual status_t getSize(off64_t *size);
76 
flags()77     virtual uint32_t flags() {
78         return 0;
79     }
80 
reconnectAtOffset(off64_t offset)81     virtual status_t reconnectAtOffset(off64_t offset) {
82         return ERROR_UNSUPPORTED;
83     }
84 
85     ////////////////////////////////////////////////////////////////////////////
86 
87     bool sniff(String8 *mimeType, float *confidence, sp<AMessage> *meta);
88 
89     // The sniffer can optionally fill in "meta" with an AMessage containing
90     // a dictionary of values that helps the corresponding extractor initialize
91     // its state without duplicating effort already exerted by the sniffer.
92     typedef bool (*SnifferFunc)(
93             const sp<DataSource> &source, String8 *mimeType,
94             float *confidence, sp<AMessage> *meta);
95 
96     static void RegisterDefaultSniffers();
97 
98     // for DRM
99     virtual sp<DecryptHandle> DrmInitialization(const char *mime = NULL) {
100         return NULL;
101     }
getDrmInfo(sp<DecryptHandle> & handle,DrmManagerClient ** client)102     virtual void getDrmInfo(sp<DecryptHandle> &handle, DrmManagerClient **client) {};
103 
getUri()104     virtual String8 getUri() {
105         return String8();
106     }
107 
108     virtual String8 getMIMEType() const;
109 
110 protected:
~DataSource()111     virtual ~DataSource() {}
112 
113 private:
114     static Mutex gSnifferMutex;
115     static List<SnifferFunc> gSniffers;
116     static bool gSniffersRegistered;
117 
118     static void RegisterSniffer_l(SnifferFunc func);
119 
120     DataSource(const DataSource &);
121     DataSource &operator=(const DataSource &);
122 };
123 
124 }  // namespace android
125 
126 #endif  // DATA_SOURCE_H_
127