Perform an orderly shutdown if possible, force disconnect if necessary

wait for up to 2 secs for the dongle to send us a "TEARDOWN", after that
forcibly shutdown the connection.

Change-Id: Ie049857cd468b7af6986d6305f725c54571b2276
related-to-bug: 7258622

3 files changed, 71 insertions, 7 deletions

diff --git a/media/libstagefright/wifi-display/source/PlaybackSession.cpp b/media/libstagefright/wifi-display/source/PlaybackSession.cpp
index c8b9afd..9c065b2 100644
--- a/media/libstagefright/wifi-display/source/PlaybackSession.cpp
+++ b/media/libstagefright/wifi-display/source/PlaybackSession.cpp
@@ -173,13 +173,11 @@ status_t WifiDisplaySource::PlaybackSession::Track::start() {
 void WifiDisplaySource::PlaybackSession::Track::stopAsync() {
     ALOGV("Track::stopAsync isAudio=%d", mIsAudio);
 
-    CHECK(mStarted);
-
     mConverter->shutdownAsync();
 
     sp<AMessage> msg = new AMessage(kWhatMediaPullerStopped, id());
 
-    if (mMediaPuller != NULL) {
+    if (mStarted && mMediaPuller != NULL) {
         mMediaPuller->stopAsync(msg);
     } else {
         msg->post();
diff --git a/media/libstagefright/wifi-display/source/WifiDisplaySource.cpp b/media/libstagefright/wifi-display/source/WifiDisplaySource.cpp
index d5ffc65..adb1549 100644
--- a/media/libstagefright/wifi-display/source/WifiDisplaySource.cpp
+++ b/media/libstagefright/wifi-display/source/WifiDisplaySource.cpp
@@ -41,7 +41,8 @@ namespace android {
 WifiDisplaySource::WifiDisplaySource(
         const sp<ANetworkSession> &netSession,
         const sp<IRemoteDisplayClient> &client)
-    : mNetSession(netSession),
+    : mState(INITIALIZED),
+      mNetSession(netSession),
       mClient(client),
       mSessionID(0),
       mStopReplyID(0),
@@ -61,6 +62,8 @@ WifiDisplaySource::~WifiDisplaySource() {
 }
 
 status_t WifiDisplaySource::start(const char *iface) {
+    CHECK_EQ(mState, INITIALIZED);
+
     sp<AMessage> msg = new AMessage(kWhatStart, id());
     msg->setString("iface", iface);
 
@@ -137,6 +140,10 @@ void WifiDisplaySource::onMessageReceived(const sp<AMessage> &msg) {
                 }
             }
 
+            if (err == OK) {
+                mState = AWAITING_CLIENT_CONNECTION;
+            }
+
             sp<AMessage> response = new AMessage;
             response->setInt32("err", err);
             response->postReply(replyID);
@@ -190,6 +197,8 @@ void WifiDisplaySource::onMessageReceived(const sp<AMessage> &msg) {
                         break;
                     }
 
+                    CHECK_EQ(mState, AWAITING_CLIENT_CONNECTION);
+
                     CHECK(msg->findString("client-ip", &mClientInfo.mRemoteIP));
                     CHECK(msg->findString("server-ip", &mClientInfo.mLocalIP));
 
@@ -208,6 +217,8 @@ void WifiDisplaySource::onMessageReceived(const sp<AMessage> &msg) {
 
                     ALOGI("We now have a client (%d) connected.", sessionID);
 
+                    mState = AWAITING_CLIENT_SETUP;
+
                     status_t err = sendM1(sessionID);
                     CHECK_EQ(err, (status_t)OK);
                     break;
@@ -234,14 +245,24 @@ void WifiDisplaySource::onMessageReceived(const sp<AMessage> &msg) {
         {
             CHECK(msg->senderAwaitsResponse(&mStopReplyID));
 
-            if (mClientSessionID != 0
-                    && mClientInfo.mPlaybackSessionID != -1) {
+            CHECK_LT(mState, AWAITING_CLIENT_TEARDOWN);
+
+            if (mState >= AWAITING_CLIENT_PLAY) {
+                // We have a session, i.e. a previous SETUP succeeded.
+
                 status_t err = sendM5(
                         mClientSessionID, true /* requestShutdown */);
 
                 if (err == OK) {
+                    mState = AWAITING_CLIENT_TEARDOWN;
+
+                    (new AMessage(kWhatTeardownTriggerTimedOut, id()))->post(
+                            kTeardownTriggerTimeouSecs * 1000000ll);
+
                     break;
                 }
+
+                // fall through.
             }
 
             finishStop();
@@ -293,6 +314,10 @@ void WifiDisplaySource::onMessageReceived(const sp<AMessage> &msg) {
                             mClientInfo.mPlaybackSession->height(),
                             0 /* flags */);
                 }
+
+                if (mState == ABOUT_TO_PLAY) {
+                    mState = PLAYING;
+                }
             } else if (what == PlaybackSession::kWhatSessionDestroyed) {
                 disconnectClient2();
             } else {
@@ -339,6 +364,18 @@ void WifiDisplaySource::onMessageReceived(const sp<AMessage> &msg) {
             break;
         }
 
+        case kWhatTeardownTriggerTimedOut:
+        {
+            if (mState == AWAITING_CLIENT_TEARDOWN) {
+                ALOGI("TEARDOWN trigger timed out, forcing disconnection.");
+
+                CHECK_NE(mStopReplyID, 0);
+                finishStop();
+                break;
+            }
+            break;
+        }
+
 #if REQUIRE_HDCP
         case kWhatHDCPNotify:
         {
@@ -1020,6 +1057,8 @@ status_t WifiDisplaySource::onSetupRequest(
         return err;
     }
 
+    mState = AWAITING_CLIENT_PLAY;
+
     scheduleReaper();
     scheduleKeepAlive(sessionID);
 
@@ -1057,6 +1096,9 @@ status_t WifiDisplaySource::onPlayRequest(
 
     playbackSession->finishPlay();
 
+    CHECK_EQ(mState, AWAITING_CLIENT_PLAY);
+    mState = ABOUT_TO_PLAY;
+
     return OK;
 }
 
@@ -1107,7 +1149,8 @@ status_t WifiDisplaySource::onTeardownRequest(
 
     mNetSession->sendRequest(sessionID, response.c_str());
 
-    if (mStopReplyID != 0) {
+    if (mState == AWAITING_CLIENT_TEARDOWN) {
+        CHECK_NE(mStopReplyID, 0);
         finishStop();
     } else {
         mClient->onDisplayError(IRemoteDisplayClient::kDisplayErrorUnknown);
@@ -1119,6 +1162,8 @@ status_t WifiDisplaySource::onTeardownRequest(
 void WifiDisplaySource::finishStop() {
     ALOGV("finishStop");
 
+    mState = STOPPING;
+
     disconnectClientAsync();
 }
 
@@ -1153,6 +1198,7 @@ void WifiDisplaySource::finishStop2() {
     }
 
     ALOGI("We're stopped.");
+    mState = STOPPED;
 
     status_t err = OK;
 
diff --git a/media/libstagefright/wifi-display/source/WifiDisplaySource.h b/media/libstagefright/wifi-display/source/WifiDisplaySource.h
index ade623a..8c043cd 100644
--- a/media/libstagefright/wifi-display/source/WifiDisplaySource.h
+++ b/media/libstagefright/wifi-display/source/WifiDisplaySource.h
@@ -55,6 +55,18 @@ private:
     struct HDCPObserver;
 #endif
 
+    enum State {
+        INITIALIZED,
+        AWAITING_CLIENT_CONNECTION,
+        AWAITING_CLIENT_SETUP,
+        AWAITING_CLIENT_PLAY,
+        ABOUT_TO_PLAY,
+        PLAYING,
+        AWAITING_CLIENT_TEARDOWN,
+        STOPPING,
+        STOPPED,
+    };
+
     enum {
         kWhatStart,
         kWhatRTSPNotify,
@@ -64,6 +76,7 @@ private:
         kWhatKeepAlive,
         kWhatHDCPNotify,
         kWhatFinishStop2,
+        kWhatTeardownTriggerTimedOut,
     };
 
     struct ResponseID {
@@ -82,11 +95,18 @@ private:
 
     static const int64_t kReaperIntervalUs = 1000000ll;
 
+    // We request that the dongle send us a "TEARDOWN" in order to
+    // perform an orderly shutdown. We're willing to wait up to 2 secs
+    // for this message to arrive, after that we'll force a disconnect
+    // instead.
+    static const int64_t kTeardownTriggerTimeouSecs = 2;
+
     static const int64_t kPlaybackSessionTimeoutSecs = 30;
 
     static const int64_t kPlaybackSessionTimeoutUs =
         kPlaybackSessionTimeoutSecs * 1000000ll;
 
+    State mState;
     sp<ANetworkSession> mNetSession;
     sp<IRemoteDisplayClient> mClient;
     struct in_addr mInterfaceAddr;