mediametadataretriever.cpp revision 3856b090cd04ba5dd4a59a12430ed724d5995909 
1/*
2**
3** Copyright 2008, The Android Open Source Project
4**
5** Licensed under the Apache License, Version 2.0 (the "License");
6** you may not use this file except in compliance with the License.
7** You may obtain a copy of the License at
8**
9**     http://www.apache.org/licenses/LICENSE-2.0
10**
11** Unless required by applicable law or agreed to in writing, software
12** distributed under the License is distributed on an "AS IS" BASIS,
13** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14** See the License for the specific language governing permissions and
15** limitations under the License.
16*/
17
18//#define LOG_NDEBUG 0
19#define LOG_TAG "MediaMetadataRetriever"
20
21#include <binder/IServiceManager.h>
22#include <binder/IPCThreadState.h>
23#include <media/mediametadataretriever.h>
24#include <media/IMediaPlayerService.h>
25#include <utils/Log.h>
26#include <dlfcn.h>
27
28namespace android {
29
30// client singleton for binder interface to service
31Mutex MediaMetadataRetriever::sServiceLock;
32sp<IMediaPlayerService> MediaMetadataRetriever::sService;
33sp<MediaMetadataRetriever::DeathNotifier> MediaMetadataRetriever::sDeathNotifier;
34
35const sp<IMediaPlayerService>& MediaMetadataRetriever::getService()
36{
37    Mutex::Autolock lock(sServiceLock);
38    if (sService.get() == 0) {
39        sp<IServiceManager> sm = defaultServiceManager();
40        sp<IBinder> binder;
41        do {
42            binder = sm->getService(String16("media.player"));
43            if (binder != 0) {
44                break;
45            }
46            LOGW("MediaPlayerService not published, waiting...");
47            usleep(500000); // 0.5 s
48        } while(true);
49        if (sDeathNotifier == NULL) {
50            sDeathNotifier = new DeathNotifier();
51        }
52        binder->linkToDeath(sDeathNotifier);
53        sService = interface_cast<IMediaPlayerService>(binder);
54    }
55    LOGE_IF(sService == 0, "no MediaPlayerService!?");
56    return sService;
57}
58
59MediaMetadataRetriever::MediaMetadataRetriever()
60{
61    ALOGV("constructor");
62    const sp<IMediaPlayerService>& service(getService());
63    if (service == 0) {
64        LOGE("failed to obtain MediaMetadataRetrieverService");
65        return;
66    }
67    sp<IMediaMetadataRetriever> retriever(service->createMetadataRetriever(getpid()));
68    if (retriever == 0) {
69        LOGE("failed to create IMediaMetadataRetriever object from server");
70    }
71    mRetriever = retriever;
72}
73
74MediaMetadataRetriever::~MediaMetadataRetriever()
75{
76    ALOGV("destructor");
77    disconnect();
78    IPCThreadState::self()->flushCommands();
79}
80
81void MediaMetadataRetriever::disconnect()
82{
83    ALOGV("disconnect");
84    sp<IMediaMetadataRetriever> retriever;
85    {
86        Mutex::Autolock _l(mLock);
87        retriever = mRetriever;
88        mRetriever.clear();
89    }
90    if (retriever != 0) {
91        retriever->disconnect();
92    }
93}
94
95status_t MediaMetadataRetriever::setDataSource(
96        const char *srcUrl, const KeyedVector<String8, String8> *headers)
97{
98    ALOGV("setDataSource");
99    Mutex::Autolock _l(mLock);
100    if (mRetriever == 0) {
101        LOGE("retriever is not initialized");
102        return INVALID_OPERATION;
103    }
104    if (srcUrl == NULL) {
105        LOGE("data source is a null pointer");
106        return UNKNOWN_ERROR;
107    }
108    ALOGV("data source (%s)", srcUrl);
109    return mRetriever->setDataSource(srcUrl, headers);
110}
111
112status_t MediaMetadataRetriever::setDataSource(int fd, int64_t offset, int64_t length)
113{
114    ALOGV("setDataSource(%d, %lld, %lld)", fd, offset, length);
115    Mutex::Autolock _l(mLock);
116    if (mRetriever == 0) {
117        LOGE("retriever is not initialized");
118        return INVALID_OPERATION;
119    }
120    if (fd < 0 || offset < 0 || length < 0) {
121        LOGE("Invalid negative argument");
122        return UNKNOWN_ERROR;
123    }
124    return mRetriever->setDataSource(fd, offset, length);
125}
126
127sp<IMemory> MediaMetadataRetriever::getFrameAtTime(int64_t timeUs, int option)
128{
129    ALOGV("getFrameAtTime: time(%lld us) option(%d)", timeUs, option);
130    Mutex::Autolock _l(mLock);
131    if (mRetriever == 0) {
132        LOGE("retriever is not initialized");
133        return NULL;
134    }
135    return mRetriever->getFrameAtTime(timeUs, option);
136}
137
138const char* MediaMetadataRetriever::extractMetadata(int keyCode)
139{
140    ALOGV("extractMetadata(%d)", keyCode);
141    Mutex::Autolock _l(mLock);
142    if (mRetriever == 0) {
143        LOGE("retriever is not initialized");
144        return NULL;
145    }
146    return mRetriever->extractMetadata(keyCode);
147}
148
149sp<IMemory> MediaMetadataRetriever::extractAlbumArt()
150{
151    ALOGV("extractAlbumArt");
152    Mutex::Autolock _l(mLock);
153    if (mRetriever == 0) {
154        LOGE("retriever is not initialized");
155        return NULL;
156    }
157    return mRetriever->extractAlbumArt();
158}
159
160void MediaMetadataRetriever::DeathNotifier::binderDied(const wp<IBinder>& who) {
161    Mutex::Autolock lock(MediaMetadataRetriever::sServiceLock);
162    MediaMetadataRetriever::sService.clear();
163    LOGW("MediaMetadataRetriever server died!");
164}
165
166MediaMetadataRetriever::DeathNotifier::~DeathNotifier()
167{
168    Mutex::Autolock lock(sServiceLock);
169    if (sService != 0) {
170        sService->asBinder()->unlinkToDeath(this);
171    }
172}
173
174}; // namespace android
175