IMediaMetadataRetriever.cpp revision af8791e112c8072452bd14ef3c43a47511d19542 
1/*
2**
3** Copyright (C) 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#include <stdint.h>
19#include <sys/types.h>
20#include <binder/Parcel.h>
21#include <SkBitmap.h>
22#include <media/IMediaMetadataRetriever.h>
23#include <utils/String8.h>
24
25// The binder is supposed to propagate the scheduler group across
26// the binder interface so that remote calls are executed with
27// the same priority as local calls. This is currently not working
28// so this change puts in a temporary hack to fix the issue with
29// metadata retrieval which can be a huge CPU hit if done on a
30// foreground thread.
31#ifndef DISABLE_GROUP_SCHEDULE_HACK
32
33/* desktop Linux needs a little help with gettid() */
34#if defined(HAVE_GETTID) && !defined(HAVE_ANDROID_OS)
35#define __KERNEL__
36# include <linux/unistd.h>
37#ifdef _syscall0
38_syscall0(pid_t,gettid)
39#else
40pid_t gettid() { return syscall(__NR_gettid);}
41#endif
42#undef __KERNEL__
43#endif
44
45static int myTid() {
46#ifdef HAVE_GETTID
47    return gettid();
48#else
49    return getpid();
50#endif
51}
52
53#undef LOG_TAG
54#define LOG_TAG "IMediaMetadataRetriever"
55#include <utils/Log.h>
56#include <cutils/sched_policy.h>
57
58namespace android {
59
60static void sendSchedPolicy(Parcel& data)
61{
62    SchedPolicy policy;
63    get_sched_policy(myTid(), &policy);
64    data.writeInt32(policy);
65}
66
67static void setSchedPolicy(const Parcel& data)
68{
69    SchedPolicy policy = (SchedPolicy) data.readInt32();
70    set_sched_policy(myTid(), policy);
71}
72static void restoreSchedPolicy()
73{
74    set_sched_policy(myTid(), SP_FOREGROUND);
75}
76}; // end namespace android
77#endif
78
79namespace android {
80
81enum {
82    DISCONNECT = IBinder::FIRST_CALL_TRANSACTION,
83    SET_DATA_SOURCE_URL,
84    SET_DATA_SOURCE_FD,
85    GET_FRAME_AT_TIME,
86    EXTRACT_ALBUM_ART,
87    EXTRACT_METADATA,
88};
89
90class BpMediaMetadataRetriever: public BpInterface<IMediaMetadataRetriever>
91{
92public:
93    BpMediaMetadataRetriever(const sp<IBinder>& impl)
94        : BpInterface<IMediaMetadataRetriever>(impl)
95    {
96    }
97
98    // disconnect from media metadata retriever service
99    void disconnect()
100    {
101        Parcel data, reply;
102        data.writeInterfaceToken(IMediaMetadataRetriever::getInterfaceDescriptor());
103        remote()->transact(DISCONNECT, data, &reply);
104    }
105
106    status_t setDataSource(
107            const char *srcUrl, const KeyedVector<String8, String8> *headers)
108    {
109        Parcel data, reply;
110        data.writeInterfaceToken(IMediaMetadataRetriever::getInterfaceDescriptor());
111        data.writeCString(srcUrl);
112
113        if (headers == NULL) {
114            data.writeInt32(0);
115        } else {
116            // serialize the headers
117            data.writeInt32(headers->size());
118            for (size_t i = 0; i < headers->size(); ++i) {
119                data.writeString8(headers->keyAt(i));
120                data.writeString8(headers->valueAt(i));
121            }
122        }
123
124        remote()->transact(SET_DATA_SOURCE_URL, data, &reply);
125        return reply.readInt32();
126    }
127
128    status_t setDataSource(int fd, int64_t offset, int64_t length)
129    {
130        Parcel data, reply;
131        data.writeInterfaceToken(IMediaMetadataRetriever::getInterfaceDescriptor());
132        data.writeFileDescriptor(fd);
133        data.writeInt64(offset);
134        data.writeInt64(length);
135        remote()->transact(SET_DATA_SOURCE_FD, data, &reply);
136        return reply.readInt32();
137    }
138
139    sp<IMemory> getFrameAtTime(int64_t timeUs, int option)
140    {
141        LOGV("getTimeAtTime: time(%lld us) and option(%d)", timeUs, option);
142        Parcel data, reply;
143        data.writeInterfaceToken(IMediaMetadataRetriever::getInterfaceDescriptor());
144        data.writeInt64(timeUs);
145        data.writeInt32(option);
146#ifndef DISABLE_GROUP_SCHEDULE_HACK
147        sendSchedPolicy(data);
148#endif
149        remote()->transact(GET_FRAME_AT_TIME, data, &reply);
150        status_t ret = reply.readInt32();
151        if (ret != NO_ERROR) {
152            return NULL;
153        }
154        return interface_cast<IMemory>(reply.readStrongBinder());
155    }
156
157    sp<IMemory> extractAlbumArt()
158    {
159        Parcel data, reply;
160        data.writeInterfaceToken(IMediaMetadataRetriever::getInterfaceDescriptor());
161#ifndef DISABLE_GROUP_SCHEDULE_HACK
162        sendSchedPolicy(data);
163#endif
164        remote()->transact(EXTRACT_ALBUM_ART, data, &reply);
165        status_t ret = reply.readInt32();
166        if (ret != NO_ERROR) {
167            return NULL;
168        }
169        return interface_cast<IMemory>(reply.readStrongBinder());
170    }
171
172    const char* extractMetadata(int keyCode)
173    {
174        Parcel data, reply;
175        data.writeInterfaceToken(IMediaMetadataRetriever::getInterfaceDescriptor());
176#ifndef DISABLE_GROUP_SCHEDULE_HACK
177        sendSchedPolicy(data);
178#endif
179        data.writeInt32(keyCode);
180        remote()->transact(EXTRACT_METADATA, data, &reply);
181        status_t ret = reply.readInt32();
182        if (ret != NO_ERROR) {
183            return NULL;
184        }
185        return reply.readCString();
186    }
187};
188
189IMPLEMENT_META_INTERFACE(MediaMetadataRetriever, "android.media.IMediaMetadataRetriever");
190
191// ----------------------------------------------------------------------
192
193status_t BnMediaMetadataRetriever::onTransact(
194    uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags)
195{
196    switch (code) {
197        case DISCONNECT: {
198            CHECK_INTERFACE(IMediaMetadataRetriever, data, reply);
199            disconnect();
200            return NO_ERROR;
201        } break;
202        case SET_DATA_SOURCE_URL: {
203            CHECK_INTERFACE(IMediaMetadataRetriever, data, reply);
204            const char* srcUrl = data.readCString();
205
206            KeyedVector<String8, String8> headers;
207            int32_t numHeaders = data.readInt32();
208            for (int i = 0; i < numHeaders; ++i) {
209                String8 key = data.readString8();
210                String8 value = data.readString8();
211                headers.add(key, value);
212            }
213
214            reply->writeInt32(
215                    setDataSource(srcUrl, numHeaders > 0 ? &headers : NULL));
216
217            return NO_ERROR;
218        } break;
219        case SET_DATA_SOURCE_FD: {
220            CHECK_INTERFACE(IMediaMetadataRetriever, data, reply);
221            int fd = dup(data.readFileDescriptor());
222            int64_t offset = data.readInt64();
223            int64_t length = data.readInt64();
224            reply->writeInt32(setDataSource(fd, offset, length));
225            return NO_ERROR;
226        } break;
227        case GET_FRAME_AT_TIME: {
228            CHECK_INTERFACE(IMediaMetadataRetriever, data, reply);
229            int64_t timeUs = data.readInt64();
230            int option = data.readInt32();
231            LOGV("getTimeAtTime: time(%lld us) and option(%d)", timeUs, option);
232#ifndef DISABLE_GROUP_SCHEDULE_HACK
233            setSchedPolicy(data);
234#endif
235            sp<IMemory> bitmap = getFrameAtTime(timeUs, option);
236            if (bitmap != 0) {  // Don't send NULL across the binder interface
237                reply->writeInt32(NO_ERROR);
238                reply->writeStrongBinder(bitmap->asBinder());
239            } else {
240                reply->writeInt32(UNKNOWN_ERROR);
241            }
242#ifndef DISABLE_GROUP_SCHEDULE_HACK
243            restoreSchedPolicy();
244#endif
245            return NO_ERROR;
246        } break;
247        case EXTRACT_ALBUM_ART: {
248            CHECK_INTERFACE(IMediaMetadataRetriever, data, reply);
249#ifndef DISABLE_GROUP_SCHEDULE_HACK
250            setSchedPolicy(data);
251#endif
252            sp<IMemory> albumArt = extractAlbumArt();
253            if (albumArt != 0) {  // Don't send NULL across the binder interface
254                reply->writeInt32(NO_ERROR);
255                reply->writeStrongBinder(albumArt->asBinder());
256            } else {
257                reply->writeInt32(UNKNOWN_ERROR);
258            }
259#ifndef DISABLE_GROUP_SCHEDULE_HACK
260            restoreSchedPolicy();
261#endif
262            return NO_ERROR;
263        } break;
264        case EXTRACT_METADATA: {
265            CHECK_INTERFACE(IMediaMetadataRetriever, data, reply);
266#ifndef DISABLE_GROUP_SCHEDULE_HACK
267            setSchedPolicy(data);
268#endif
269            int keyCode = data.readInt32();
270            const char* value = extractMetadata(keyCode);
271            if (value != NULL) {  // Don't send NULL across the binder interface
272                reply->writeInt32(NO_ERROR);
273                reply->writeCString(value);
274            } else {
275                reply->writeInt32(UNKNOWN_ERROR);
276            }
277#ifndef DISABLE_GROUP_SCHEDULE_HACK
278            restoreSchedPolicy();
279#endif
280            return NO_ERROR;
281        } break;
282        default:
283            return BBinder::onTransact(code, data, reply, flags);
284    }
285}
286
287// ----------------------------------------------------------------------------
288
289}; // namespace android
290