summaryrefslogtreecommitdiffstats
path: root/media/libstagefright/wifi-display/TimeSyncer.h
diff options
context:
space:
mode:
Diffstat (limited to 'media/libstagefright/wifi-display/TimeSyncer.h')
-rw-r--r--media/libstagefright/wifi-display/TimeSyncer.h109
1 files changed, 0 insertions, 109 deletions
diff --git a/media/libstagefright/wifi-display/TimeSyncer.h b/media/libstagefright/wifi-display/TimeSyncer.h
deleted file mode 100644
index 4e7571f..0000000
--- a/media/libstagefright/wifi-display/TimeSyncer.h
+++ /dev/null
@@ -1,109 +0,0 @@
-/*
- * Copyright 2013, The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#ifndef TIME_SYNCER_H_
-
-#define TIME_SYNCER_H_
-
-#include <media/stagefright/foundation/AHandler.h>
-
-namespace android {
-
-struct ANetworkSession;
-
-/*
- TimeSyncer allows us to synchronize time between a client and a server.
- The client sends a UDP packet containing its send-time to the server,
- the server sends that packet back to the client amended with information
- about when it was received as well as the time the reply was sent back.
- Finally the client receives the reply and has now enough information to
- compute the clock offset between client and server assuming that packet
- exchange is symmetric, i.e. time for a packet client->server and
- server->client is roughly equal.
- This exchange is repeated a number of times and the average offset computed
- over the 30% of packets that had the lowest roundtrip times.
- The offset is determined every 10 secs to account for slight differences in
- clock frequency.
-*/
-struct TimeSyncer : public AHandler {
- enum {
- kWhatError,
- kWhatTimeOffset,
- };
- TimeSyncer(
- const sp<ANetworkSession> &netSession,
- const sp<AMessage> &notify);
-
- void startServer(unsigned localPort);
- void startClient(const char *remoteHost, unsigned remotePort);
-
-protected:
- virtual ~TimeSyncer();
-
- virtual void onMessageReceived(const sp<AMessage> &msg);
-
-private:
- enum {
- kWhatStartServer,
- kWhatStartClient,
- kWhatUDPNotify,
- kWhatSendPacket,
- kWhatTimedOut,
- };
-
- struct TimeInfo {
- int64_t mT1; // client timestamp at send
- int64_t mT2; // server timestamp at receive
- int64_t mT3; // server timestamp at send
- int64_t mT4; // client timestamp at receive
- };
-
- enum {
- kNumPacketsPerBatch = 30,
- };
- static const int64_t kTimeoutDelayUs = 500000ll;
- static const int64_t kBatchDelayUs = 60000000ll; // every minute
-
- sp<ANetworkSession> mNetSession;
- sp<AMessage> mNotify;
-
- bool mIsServer;
- bool mConnected;
- int32_t mUDPSession;
- uint32_t mSeqNo;
- double mTotalTimeUs;
-
- Vector<TimeInfo> mHistory;
-
- int64_t mPendingT1;
- int32_t mTimeoutGeneration;
-
- void postSendPacket(int64_t delayUs = 0ll);
-
- void postTimeout();
- void cancelTimeout();
-
- void notifyError(status_t err);
- void notifyOffset();
-
- static int CompareRountripTime(const TimeInfo *ti1, const TimeInfo *ti2);
-
- DISALLOW_EVIL_CONSTRUCTORS(TimeSyncer);
-};
-
-} // namespace android
-
-#endif // TIME_SYNCER_H_