NuCachedSource2.h revision 48296b792a8d68358de74141fa80bd5bd84d0307 
1/*
2 * Copyright (C) 2010 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 NU_CACHED_SOURCE_2_H_
18
19#define NU_CACHED_SOURCE_2_H_
20
21#include <media/stagefright/foundation/ABase.h>
22#include <media/stagefright/foundation/AHandlerReflector.h>
23#include <media/stagefright/DataSource.h>
24
25namespace android {
26
27struct ALooper;
28struct PageCache;
29
30struct NuCachedSource2 : public DataSource {
31    NuCachedSource2(
32            const sp<DataSource> &source,
33            const char *cacheConfig = NULL,
34            bool disconnectAtHighwatermark = false);
35
36    virtual status_t initCheck() const;
37
38    virtual ssize_t readAt(off64_t offset, void *data, size_t size);
39
40    virtual void disconnect();
41
42    virtual status_t getSize(off64_t *size);
43    virtual uint32_t flags();
44
45    virtual sp<DecryptHandle> DrmInitialization(const char* mime);
46    virtual void getDrmInfo(sp<DecryptHandle> &handle, DrmManagerClient **client);
47    virtual String8 getUri();
48
49    virtual String8 getMIMEType() const;
50
51    ////////////////////////////////////////////////////////////////////////////
52
53    size_t cachedSize();
54    size_t approxDataRemaining(status_t *finalStatus) const;
55
56    void resumeFetchingIfNecessary();
57
58    // The following methods are supported only if the
59    // data source is HTTP-based; otherwise, ERROR_UNSUPPORTED
60    // is returned.
61    status_t getEstimatedBandwidthKbps(int32_t *kbps);
62    status_t setCacheStatCollectFreq(int32_t freqMs);
63
64    static void RemoveCacheSpecificHeaders(
65            KeyedVector<String8, String8> *headers,
66            String8 *cacheConfig,
67            bool *disconnectAtHighwatermark);
68
69protected:
70    virtual ~NuCachedSource2();
71
72private:
73    friend struct AHandlerReflector<NuCachedSource2>;
74
75    enum {
76        kPageSize                       = 65536,
77        kDefaultHighWaterThreshold      = 20 * 1024 * 1024,
78        kDefaultLowWaterThreshold       = 4 * 1024 * 1024,
79
80        // Read data after a 15 sec timeout whether we're actively
81        // fetching or not.
82        kDefaultKeepAliveIntervalUs     = 15000000,
83    };
84
85    enum {
86        kWhatFetchMore  = 'fetc',
87        kWhatRead       = 'read',
88    };
89
90    enum {
91        kMaxNumRetries = 10,
92    };
93
94    sp<DataSource> mSource;
95    sp<AHandlerReflector<NuCachedSource2> > mReflector;
96    sp<ALooper> mLooper;
97
98    Mutex mSerializer;
99    mutable Mutex mLock;
100    Condition mCondition;
101
102    PageCache *mCache;
103    off64_t mCacheOffset;
104    status_t mFinalStatus;
105    off64_t mLastAccessPos;
106    sp<AMessage> mAsyncResult;
107    bool mFetching;
108    bool mDisconnecting;
109    int64_t mLastFetchTimeUs;
110
111    int32_t mNumRetriesLeft;
112
113    size_t mHighwaterThresholdBytes;
114    size_t mLowwaterThresholdBytes;
115
116    // If the keep-alive interval is 0, keep-alives are disabled.
117    int64_t mKeepAliveIntervalUs;
118
119    bool mDisconnectAtHighwatermark;
120
121    void onMessageReceived(const sp<AMessage> &msg);
122    void onFetch();
123    void onRead(const sp<AMessage> &msg);
124
125    void fetchInternal();
126    ssize_t readInternal(off64_t offset, void *data, size_t size);
127    status_t seekInternal_l(off64_t offset);
128
129    size_t approxDataRemaining_l(status_t *finalStatus) const;
130
131    void restartPrefetcherIfNecessary_l(
132            bool ignoreLowWaterThreshold = false, bool force = false);
133
134    void updateCacheParamsFromSystemProperty();
135    void updateCacheParamsFromString(const char *s);
136
137    DISALLOW_EVIL_CONSTRUCTORS(NuCachedSource2);
138};
139
140}  // namespace android
141
142#endif  // NU_CACHED_SOURCE_2_H_
143