DataSource.cpp revision fc9ba09e3bb368f823d473f5e2bb9aa32dba6289 
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#include "include/AMRExtractor.h"
18#include "include/MP3Extractor.h"
19#include "include/MPEG4Extractor.h"
20#include "include/WAVExtractor.h"
21
22#include <media/stagefright/CachingDataSource.h>
23#include <media/stagefright/DataSource.h>
24#include <media/stagefright/FileSource.h>
25#include <media/stagefright/HTTPDataSource.h>
26#include <media/stagefright/MediaErrors.h>
27#include <utils/String8.h>
28
29namespace android {
30
31bool DataSource::getUInt16(off_t offset, uint16_t *x) {
32    *x = 0;
33
34    uint8_t byte[2];
35    if (readAt(offset, byte, 2) != 2) {
36        return false;
37    }
38
39    *x = (byte[0] << 8) | byte[1];
40
41    return true;
42}
43
44status_t DataSource::getSize(off_t *size) {
45    *size = 0;
46
47    return ERROR_UNSUPPORTED;
48}
49
50////////////////////////////////////////////////////////////////////////////////
51
52Mutex DataSource::gSnifferMutex;
53List<DataSource::SnifferFunc> DataSource::gSniffers;
54
55bool DataSource::sniff(String8 *mimeType, float *confidence) {
56    *mimeType = "";
57    *confidence = 0.0f;
58
59    Mutex::Autolock autoLock(gSnifferMutex);
60    for (List<SnifferFunc>::iterator it = gSniffers.begin();
61         it != gSniffers.end(); ++it) {
62        String8 newMimeType;
63        float newConfidence;
64        if ((*it)(this, &newMimeType, &newConfidence)) {
65            if (newConfidence > *confidence) {
66                *mimeType = newMimeType;
67                *confidence = newConfidence;
68            }
69        }
70    }
71
72    return *confidence > 0.0;
73}
74
75// static
76void DataSource::RegisterSniffer(SnifferFunc func) {
77    Mutex::Autolock autoLock(gSnifferMutex);
78
79    for (List<SnifferFunc>::iterator it = gSniffers.begin();
80         it != gSniffers.end(); ++it) {
81        if (*it == func) {
82            return;
83        }
84    }
85
86    gSniffers.push_back(func);
87}
88
89// static
90void DataSource::RegisterDefaultSniffers() {
91    RegisterSniffer(SniffMP3);
92    RegisterSniffer(SniffMPEG4);
93    RegisterSniffer(SniffAMR);
94    RegisterSniffer(SniffWAV);
95}
96
97// static
98sp<DataSource> DataSource::CreateFromURI(const char *uri) {
99    sp<DataSource> source;
100    if (!strncasecmp("file://", uri, 7)) {
101        source = new FileSource(uri + 7);
102    } else if (!strncasecmp("http://", uri, 7)) {
103        source = new HTTPDataSource(uri);
104        source = new CachingDataSource(source, 64 * 1024, 10);
105    } else {
106        // Assume it's a filename.
107        source = new FileSource(uri);
108    }
109
110    if (source == NULL || source->initCheck() != OK) {
111        return NULL;
112    }
113
114    return source;
115}
116
117}  // namespace android
118