DataSource.h revision 78f00edc6376657e8931a45a80abf36f2f6ac841 
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#include <media/stagefright/MediaErrors.h>
23#include <utils/Errors.h>
24#include <utils/RefBase.h>
25#include <utils/threads.h>
26#include <drm/DrmManagerClient.h>
27
28namespace android {
29
30class String8;
31
32class DataSource : public RefBase {
33public:
34    enum Flags {
35        kWantsPrefetching      = 1,
36        kStreamedFromLocalHost = 2,
37        kIsCachingDataSource   = 4,
38        kIsHTTPBasedSource     = 8,
39        kIsLocalFileSource     = 16,
40    };
41
42    DataSource() {}
43
44    virtual status_t initCheck() const = 0;
45
46    // Returns the number of bytes read, or -1 on failure. It's not an error if
47    // this returns zero; it just means the given offset is equal to, or
48    // beyond, the end of the source.
49    virtual ssize_t readAt(off64_t offset, void *data, size_t size) = 0;
50
51    // Convenience methods:
52    bool getUInt16(off64_t offset, uint16_t *x);
53    bool getUInt24(off64_t offset, uint32_t *x); // 3 byte int, returned as a 32-bit int
54    bool getUInt32(off64_t offset, uint32_t *x);
55    bool getUInt64(off64_t offset, uint64_t *x);
56
57    // read either int<N> or int<2N> into a uint<2N>_t, size is the int size in bytes.
58    bool getUInt16Var(off64_t offset, uint16_t *x, size_t size);
59    bool getUInt32Var(off64_t offset, uint32_t *x, size_t size);
60    bool getUInt64Var(off64_t offset, uint64_t *x, size_t size);
61
62    // May return ERROR_UNSUPPORTED.
63    virtual status_t getSize(off64_t *size);
64
65    virtual uint32_t flags() {
66        return 0;
67    }
68
69    virtual String8 toString() {
70        return String8("<unspecified>");
71    }
72
73    virtual status_t reconnectAtOffset(off64_t /*offset*/) {
74        return ERROR_UNSUPPORTED;
75    }
76
77    ////////////////////////////////////////////////////////////////////////////
78
79    // for DRM
80    virtual sp<DecryptHandle> DrmInitialization(const char * /*mime*/ = NULL) {
81        return NULL;
82    }
83
84    virtual String8 getUri() {
85        return String8();
86    }
87
88    virtual String8 getMIMEType() const;
89
90    virtual void close() {};
91
92protected:
93    virtual ~DataSource() {}
94
95private:
96    DataSource(const DataSource &);
97    DataSource &operator=(const DataSource &);
98};
99
100}  // namespace android
101
102#endif  // DATA_SOURCE_H_
103