DataSource.h revision 9e9b3f5adf97cc37024d2a1b7aafe9495a432c29 
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
31namespace android {
32
33struct AMessage;
34struct AString;
35struct IMediaHTTPService;
36class String8;
37struct HTTPBase;
38
39class DataSource : public RefBase {
40public:
41    enum Flags {
42        kWantsPrefetching      = 1,
43        kStreamedFromLocalHost = 2,
44        kIsCachingDataSource   = 4,
45        kIsHTTPBasedSource     = 8,
46    };
47
48    static sp<DataSource> CreateFromURI(
49            const sp<IMediaHTTPService> &httpService,
50            const char *uri,
51            const KeyedVector<String8, String8> *headers = NULL,
52            String8 *contentType = NULL,
53            HTTPBase *httpSource = NULL);
54
55    static sp<DataSource> CreateMediaHTTP(const sp<IMediaHTTPService> &httpService);
56
57    DataSource() {}
58
59    virtual status_t initCheck() const = 0;
60
61    virtual ssize_t readAt(off64_t offset, void *data, size_t size) = 0;
62
63    // Convenience methods:
64    bool getUInt16(off64_t offset, uint16_t *x);
65    bool getUInt24(off64_t offset, uint32_t *x); // 3 byte int, returned as a 32-bit int
66    bool getUInt32(off64_t offset, uint32_t *x);
67    bool getUInt64(off64_t offset, uint64_t *x);
68
69    // May return ERROR_UNSUPPORTED.
70    virtual status_t getSize(off64_t *size);
71
72    virtual uint32_t flags() {
73        return 0;
74    }
75
76    virtual status_t reconnectAtOffset(off64_t offset) {
77        return ERROR_UNSUPPORTED;
78    }
79
80    ////////////////////////////////////////////////////////////////////////////
81
82    bool sniff(String8 *mimeType, float *confidence, sp<AMessage> *meta);
83
84    // The sniffer can optionally fill in "meta" with an AMessage containing
85    // a dictionary of values that helps the corresponding extractor initialize
86    // its state without duplicating effort already exerted by the sniffer.
87    typedef bool (*SnifferFunc)(
88            const sp<DataSource> &source, String8 *mimeType,
89            float *confidence, sp<AMessage> *meta);
90
91    static void RegisterDefaultSniffers();
92
93    // for DRM
94    virtual sp<DecryptHandle> DrmInitialization(const char *mime = NULL) {
95        return NULL;
96    }
97    virtual void getDrmInfo(sp<DecryptHandle> &handle, DrmManagerClient **client) {};
98
99    virtual String8 getUri() {
100        return String8();
101    }
102
103    virtual String8 getMIMEType() const;
104
105protected:
106    virtual ~DataSource() {}
107
108private:
109    static Mutex gSnifferMutex;
110    static List<SnifferFunc> gSniffers;
111    static bool gSniffersRegistered;
112
113    static void RegisterSniffer_l(SnifferFunc func);
114
115    DataSource(const DataSource &);
116    DataSource &operator=(const DataSource &);
117};
118
119}  // namespace android
120
121#endif  // DATA_SOURCE_H_
122