am 263c4310: am ce468a35: Stop wifi display discovery when no longer needed.

* commit '263c431017c51fc51c85454a0f9cc7979001a3c1':
  Stop wifi display discovery when no longer needed.

3 files changed, 223 insertions, 72 deletions

diff --git a/services/java/com/android/server/display/DisplayManagerService.java b/services/java/com/android/server/display/DisplayManagerService.java
index 02f26b3..bcb677f 100644
--- a/services/java/com/android/server/display/DisplayManagerService.java
+++ b/services/java/com/android/server/display/DisplayManagerService.java
@@ -35,6 +35,7 @@ import android.os.RemoteException;
 import android.os.SystemClock;
 import android.os.SystemProperties;
 import android.text.TextUtils;
+import android.util.Log;
 import android.util.Slog;
 import android.util.SparseArray;
 import android.view.Display;
@@ -173,6 +174,9 @@ public final class DisplayManagerService extends IDisplayManager.Stub {
     // The Wifi display adapter, or null if not registered.
     private WifiDisplayAdapter mWifiDisplayAdapter;
 
+    // The number of active wifi display scan requests.
+    private int mWifiDisplayScanRequestCount;
+
     // The virtual display adapter, or null if not registered.
     private VirtualDisplayAdapter mVirtualDisplayAdapter;
 
@@ -458,29 +462,81 @@ public final class DisplayManagerService extends IDisplayManager.Stub {
         }
     }
 
-    private void onCallbackDied(int pid) {
+    private void onCallbackDied(CallbackRecord record) {
         synchronized (mSyncRoot) {
-            mCallbacks.remove(pid);
+            mCallbacks.remove(record.mPid);
+            stopWifiDisplayScanLocked(record);
         }
     }
 
     @Override // Binder call
-    public void scanWifiDisplays() {
+    public void startWifiDisplayScan() {
         mContext.enforceCallingOrSelfPermission(Manifest.permission.CONFIGURE_WIFI_DISPLAY,
-                "Permission required to scan wifi displays");
+                "Permission required to start wifi display scans");
 
+        final int callingPid = Binder.getCallingPid();
         final long token = Binder.clearCallingIdentity();
         try {
             synchronized (mSyncRoot) {
+                CallbackRecord record = mCallbacks.get(callingPid);
+                if (record == null) {
+                    throw new IllegalStateException("The calling process has not "
+                            + "registered an IDisplayManagerCallback.");
+                }
+                startWifiDisplayScanLocked(record);
+            }
+        } finally {
+            Binder.restoreCallingIdentity(token);
+        }
+    }
+
+    private void startWifiDisplayScanLocked(CallbackRecord record) {
+        if (!record.mWifiDisplayScanRequested) {
+            record.mWifiDisplayScanRequested = true;
+            if (mWifiDisplayScanRequestCount++ == 0) {
                 if (mWifiDisplayAdapter != null) {
-                    mWifiDisplayAdapter.requestScanLocked();
+                    mWifiDisplayAdapter.requestStartScanLocked();
                 }
             }
+        }
+    }
+
+    @Override // Binder call
+    public void stopWifiDisplayScan() {
+        mContext.enforceCallingOrSelfPermission(Manifest.permission.CONFIGURE_WIFI_DISPLAY,
+                "Permission required to stop wifi display scans");
+
+        final int callingPid = Binder.getCallingPid();
+        final long token = Binder.clearCallingIdentity();
+        try {
+            synchronized (mSyncRoot) {
+                CallbackRecord record = mCallbacks.get(callingPid);
+                if (record == null) {
+                    throw new IllegalStateException("The calling process has not "
+                            + "registered an IDisplayManagerCallback.");
+                }
+                stopWifiDisplayScanLocked(record);
+            }
         } finally {
             Binder.restoreCallingIdentity(token);
         }
     }
 
+    private void stopWifiDisplayScanLocked(CallbackRecord record) {
+        if (record.mWifiDisplayScanRequested) {
+            record.mWifiDisplayScanRequested = false;
+            if (--mWifiDisplayScanRequestCount == 0) {
+                if (mWifiDisplayAdapter != null) {
+                    mWifiDisplayAdapter.requestStopScanLocked();
+                }
+            } else if (mWifiDisplayScanRequestCount < 0) {
+                Log.wtf(TAG, "mWifiDisplayScanRequestCount became negative: "
+                        + mWifiDisplayScanRequestCount);
+                mWifiDisplayScanRequestCount = 0;
+            }
+        }
+    }
+
     @Override // Binder call
     public void connectWifiDisplay(String address) {
         if (address == null) {
@@ -1107,6 +1163,7 @@ public final class DisplayManagerService extends IDisplayManager.Stub {
             pw.println("  mDefaultViewport=" + mDefaultViewport);
             pw.println("  mExternalTouchViewport=" + mExternalTouchViewport);
             pw.println("  mSingleDisplayDemoMode=" + mSingleDisplayDemoMode);
+            pw.println("  mWifiDisplayScanRequestCount=" + mWifiDisplayScanRequestCount);
 
             IndentingPrintWriter ipw = new IndentingPrintWriter(pw, "    ");
             ipw.increaseIndent();
@@ -1134,6 +1191,15 @@ public final class DisplayManagerService extends IDisplayManager.Stub {
                 pw.println("  Display " + displayId + ":");
                 display.dumpLocked(ipw);
             }
+
+            final int callbackCount = mCallbacks.size();
+            pw.println();
+            pw.println("Callbacks: size=" + callbackCount);
+            for (int i = 0; i < callbackCount; i++) {
+                CallbackRecord callback = mCallbacks.valueAt(i);
+                pw.println("  " + i + ": mPid=" + callback.mPid
+                        + ", mWifiDisplayScanRequested=" + callback.mWifiDisplayScanRequested);
+            }
         }
     }
 
@@ -1234,9 +1300,11 @@ public final class DisplayManagerService extends IDisplayManager.Stub {
     }
 
     private final class CallbackRecord implements DeathRecipient {
-        private final int mPid;
+        public final int mPid;
         private final IDisplayManagerCallback mCallback;
 
+        public boolean mWifiDisplayScanRequested;
+
         public CallbackRecord(int pid, IDisplayManagerCallback callback) {
             mPid = pid;
             mCallback = callback;
@@ -1247,7 +1315,7 @@ public final class DisplayManagerService extends IDisplayManager.Stub {
             if (DEBUG) {
                 Slog.d(TAG, "Display listener for pid " + mPid + " died.");
             }
-            onCallbackDied(mPid);
+            onCallbackDied(this);
         }
 
         public void notifyDisplayEventAsync(int displayId, int event) {
diff --git a/services/java/com/android/server/display/WifiDisplayAdapter.java b/services/java/com/android/server/display/WifiDisplayAdapter.java
index fdef039..cd57941 100644
--- a/services/java/com/android/server/display/WifiDisplayAdapter.java
+++ b/services/java/com/android/server/display/WifiDisplayAdapter.java
@@ -127,7 +127,7 @@ final class WifiDisplayAdapter extends DisplayAdapter {
         pw.println("mPendingStatusChangeBroadcast=" + mPendingStatusChangeBroadcast);
         pw.println("mPendingNotificationUpdate=" + mPendingNotificationUpdate);
         pw.println("mSupportsProtectedBuffers=" + mSupportsProtectedBuffers);
-
+ 
         // Try to dump the controller state.
         if (mDisplayController == null) {
             pw.println("mDisplayController=null");
@@ -157,43 +157,49 @@ final class WifiDisplayAdapter extends DisplayAdapter {
         });
     }
 
-    public void requestScanLocked() {
+    public void requestStartScanLocked() {
         if (DEBUG) {
-            Slog.d(TAG, "requestScanLocked");
+            Slog.d(TAG, "requestStartScanLocked");
         }
 
         getHandler().post(new Runnable() {
             @Override
             public void run() {
                 if (mDisplayController != null) {
-                    mDisplayController.requestScan();
+                    mDisplayController.requestStartScan();
                 }
             }
         });
     }
 
-    public void requestConnectLocked(final String address) {
+    public void requestStopScanLocked() {
         if (DEBUG) {
-            Slog.d(TAG, "requestConnectLocked: address=" + address);
+            Slog.d(TAG, "requestStopScanLocked");
         }
 
         getHandler().post(new Runnable() {
             @Override
             public void run() {
                 if (mDisplayController != null) {
-                    mDisplayController.requestConnect(address);
+                    mDisplayController.requestStopScan();
                 }
             }
         });
     }
 
-    private boolean isRememberedDisplayLocked(String address) {
-        for (WifiDisplay display : mRememberedDisplays) {
-            if (display.getDeviceAddress().equals(address)) {
-                return true;
-            }
+    public void requestConnectLocked(final String address) {
+        if (DEBUG) {
+            Slog.d(TAG, "requestConnectLocked: address=" + address);
         }
-        return false;
+
+        getHandler().post(new Runnable() {
+            @Override
+            public void run() {
+                if (mDisplayController != null) {
+                    mDisplayController.requestConnect(address);
+                }
+            }
+        });
     }
 
     public void requestPauseLocked() {
@@ -552,20 +558,20 @@ final class WifiDisplayAdapter extends DisplayAdapter {
         }
 
         @Override
-        public void onScanFinished(WifiDisplay[] availableDisplays) {
+        public void onScanResults(WifiDisplay[] availableDisplays) {
             synchronized (getSyncRoot()) {
                 availableDisplays = mPersistentDataStore.applyWifiDisplayAliases(
                         availableDisplays);
 
-                // check if any of the available displays changed canConnect status
                 boolean changed = !Arrays.equals(mAvailableDisplays, availableDisplays);
+
+                // Check whether any of the available displays changed canConnect status.
                 for (int i = 0; !changed && i<availableDisplays.length; i++) {
                     changed = availableDisplays[i].canConnect()
                             != mAvailableDisplays[i].canConnect();
                 }
 
-                if (mScanState != WifiDisplayStatus.SCAN_STATE_NOT_SCANNING || changed) {
-                    mScanState = WifiDisplayStatus.SCAN_STATE_NOT_SCANNING;
+                if (changed) {
                     mAvailableDisplays = availableDisplays;
                     fixRememberedDisplayNamesFromAvailableDisplaysLocked();
                     updateDisplaysLocked();
@@ -575,6 +581,16 @@ final class WifiDisplayAdapter extends DisplayAdapter {
         }
 
         @Override
+        public void onScanFinished() {
+            synchronized (getSyncRoot()) {
+                if (mScanState != WifiDisplayStatus.SCAN_STATE_NOT_SCANNING) {
+                    mScanState = WifiDisplayStatus.SCAN_STATE_NOT_SCANNING;
+                    scheduleStatusChangedBroadcastLocked();
+                }
+            }
+        }
+
+        @Override
         public void onDisplayConnecting(WifiDisplay display) {
             synchronized (getSyncRoot()) {
                 display = mPersistentDataStore.applyWifiDisplayAlias(display);
diff --git a/services/java/com/android/server/display/WifiDisplayController.java b/services/java/com/android/server/display/WifiDisplayController.java
index b2939fe..dbb59b2 100644
--- a/services/java/com/android/server/display/WifiDisplayController.java
+++ b/services/java/com/android/server/display/WifiDisplayController.java
@@ -27,7 +27,6 @@ import android.database.ContentObserver;
 import android.hardware.display.WifiDisplay;
 import android.hardware.display.WifiDisplaySessionInfo;
 import android.hardware.display.WifiDisplayStatus;
-import android.media.AudioManager;
 import android.media.RemoteDisplay;
 import android.net.NetworkInfo;
 import android.net.Uri;
@@ -75,12 +74,19 @@ final class WifiDisplayController implements DumpUtils.Dump {
 
     private static final int DEFAULT_CONTROL_PORT = 7236;
     private static final int MAX_THROUGHPUT = 50;
-    private static final int CONNECTION_TIMEOUT_SECONDS = 60;
+    private static final int CONNECTION_TIMEOUT_SECONDS = 30;
     private static final int RTSP_TIMEOUT_SECONDS = 30;
     private static final int RTSP_TIMEOUT_SECONDS_CERT_MODE = 120;
 
-    private static final int DISCOVER_PEERS_MAX_RETRIES = 10;
-    private static final int DISCOVER_PEERS_RETRY_DELAY_MILLIS = 500;
+    // We repeatedly issue calls to discover peers every so often for a few reasons.
+    // 1. The initial request may fail and need to retried.
+    // 2. Discovery will self-abort after any group is initiated, which may not necessarily
+    //    be what we want to have happen.
+    // 3. Discovery will self-timeout after 2 minutes, whereas we want discovery to
+    //    be occur for as long as a client is requesting it be.
+    // 4. We don't seem to get updated results for displays we've already found until
+    //    we ask to discover again, particularly for the isSessionAvailable() property.
+    private static final int DISCOVER_PEERS_INTERVAL_MILLIS = 10000;
 
     private static final int CONNECT_MAX_RETRIES = 3;
     private static final int CONNECT_RETRY_DELAY_MILLIS = 500;
@@ -103,12 +109,12 @@ final class WifiDisplayController implements DumpUtils.Dump {
     // True if Wifi display is enabled by the user.
     private boolean mWifiDisplayOnSetting;
 
+    // True if a scan was requested independent of whether one is actually in progress.
+    private boolean mScanRequested;
+
     // True if there is a call to discoverPeers in progress.
     private boolean mDiscoverPeersInProgress;
 
-    // Number of discover peers retries remaining.
-    private int mDiscoverPeersRetriesLeft;
-
     // The device to which we want to connect, or null if we want to be disconnected.
     private WifiP2pDevice mDesiredDevice;
 
@@ -209,8 +215,8 @@ final class WifiDisplayController implements DumpUtils.Dump {
         pw.println("mWfdEnabled=" + mWfdEnabled);
         pw.println("mWfdEnabling=" + mWfdEnabling);
         pw.println("mNetworkInfo=" + mNetworkInfo);
+        pw.println("mScanRequested=" + mScanRequested);
         pw.println("mDiscoverPeersInProgress=" + mDiscoverPeersInProgress);
-        pw.println("mDiscoverPeersRetriesLeft=" + mDiscoverPeersRetriesLeft);
         pw.println("mDesiredDevice=" + describeWifiP2pDevice(mDesiredDevice));
         pw.println("mConnectingDisplay=" + describeWifiP2pDevice(mConnectingDevice));
         pw.println("mDisconnectingDisplay=" + describeWifiP2pDevice(mDisconnectingDevice));
@@ -232,8 +238,18 @@ final class WifiDisplayController implements DumpUtils.Dump {
         }
     }
 
-    public void requestScan() {
-        discoverPeers();
+    public void requestStartScan() {
+        if (!mScanRequested) {
+            mScanRequested = true;
+            updateScanState();
+        }
+    }
+
+    public void requestStopScan() {
+        if (mScanRequested) {
+            mScanRequested = false;
+            updateScanState();
+        }
     }
 
     public void requestConnect(String address) {
@@ -282,6 +298,7 @@ final class WifiDisplayController implements DumpUtils.Dump {
                             mWfdEnabling = false;
                             mWfdEnabled = true;
                             reportFeatureState();
+                            updateScanState();
                         }
                     }
 
@@ -318,6 +335,7 @@ final class WifiDisplayController implements DumpUtils.Dump {
             mWfdEnabling = false;
             mWfdEnabled = false;
             reportFeatureState();
+            updateScanState();
             disconnect();
         }
     }
@@ -340,12 +358,29 @@ final class WifiDisplayController implements DumpUtils.Dump {
                 WifiDisplayStatus.FEATURE_STATE_OFF;
     }
 
-    private void discoverPeers() {
-        if (!mDiscoverPeersInProgress) {
-            mDiscoverPeersInProgress = true;
-            mDiscoverPeersRetriesLeft = DISCOVER_PEERS_MAX_RETRIES;
-            handleScanStarted();
-            tryDiscoverPeers();
+    private void updateScanState() {
+        if (mScanRequested && mWfdEnabled && mDesiredDevice == null) {
+            if (!mDiscoverPeersInProgress) {
+                Slog.i(TAG, "Starting Wifi display scan.");
+                mDiscoverPeersInProgress = true;
+                handleScanStarted();
+                tryDiscoverPeers();
+            }
+        } else {
+            if (mDiscoverPeersInProgress) {
+                // Cancel automatic retry right away.
+                mHandler.removeCallbacks(mDiscoverPeers);
+
+                // Defer actually stopping discovery if we have a connection attempt in progress.
+                // The wifi display connection attempt often fails if we are not in discovery
+                // mode.  So we allow discovery to continue until we give up trying to connect.
+                if (mDesiredDevice == null || mDesiredDevice == mConnectedDevice) {
+                    Slog.i(TAG, "Stopping Wifi display scan.");
+                    mDiscoverPeersInProgress = false;
+                    stopPeerDiscovery();
+                    handleScanFinished();
+                }
+            }
         }
     }
 
@@ -357,8 +392,9 @@ final class WifiDisplayController implements DumpUtils.Dump {
                     Slog.d(TAG, "Discover peers succeeded.  Requesting peers now.");
                 }
 
-                mDiscoverPeersInProgress = false;
-                requestPeers();
+                if (mDiscoverPeersInProgress) {
+                    requestPeers();
+                }
             }
 
             @Override
@@ -367,30 +403,28 @@ final class WifiDisplayController implements DumpUtils.Dump {
                     Slog.d(TAG, "Discover peers failed with reason " + reason + ".");
                 }
 
-                if (mDiscoverPeersInProgress) {
-                    if (reason == 0 && mDiscoverPeersRetriesLeft > 0 && mWfdEnabled) {
-                        mHandler.postDelayed(new Runnable() {
-                            @Override
-                            public void run() {
-                                if (mDiscoverPeersInProgress) {
-                                    if (mDiscoverPeersRetriesLeft > 0 && mWfdEnabled) {
-                                        mDiscoverPeersRetriesLeft -= 1;
-                                        if (DEBUG) {
-                                            Slog.d(TAG, "Retrying discovery.  Retries left: "
-                                                    + mDiscoverPeersRetriesLeft);
-                                        }
-                                        tryDiscoverPeers();
-                                    } else {
-                                        handleScanFinished();
-                                        mDiscoverPeersInProgress = false;
-                                    }
-                                }
-                            }
-                        }, DISCOVER_PEERS_RETRY_DELAY_MILLIS);
-                    } else {
-                        handleScanFinished();
-                        mDiscoverPeersInProgress = false;
-                    }
+                // Ignore the error.
+                // We will retry automatically in a little bit.
+            }
+        });
+
+        // Retry discover peers periodically until stopped.
+        mHandler.postDelayed(mDiscoverPeers, DISCOVER_PEERS_INTERVAL_MILLIS);
+    }
+
+    private void stopPeerDiscovery() {
+        mWifiP2pManager.stopPeerDiscovery(mWifiP2pChannel, new ActionListener() {
+            @Override
+            public void onSuccess() {
+                if (DEBUG) {
+                    Slog.d(TAG, "Stop peer discovery succeeded.");
+                }
+            }
+
+            @Override
+            public void onFailure(int reason) {
+                if (DEBUG) {
+                    Slog.d(TAG, "Stop peer discovery failed with reason " + reason + ".");
                 }
             }
         });
@@ -415,7 +449,9 @@ final class WifiDisplayController implements DumpUtils.Dump {
                     }
                 }
 
-                handleScanFinished();
+                if (mDiscoverPeersInProgress) {
+                    handleScanResults();
+                }
             }
         });
     }
@@ -429,7 +465,7 @@ final class WifiDisplayController implements DumpUtils.Dump {
         });
     }
 
-    private void handleScanFinished() {
+    private void handleScanResults() {
         final int count = mAvailableWifiDisplayPeers.size();
         final WifiDisplay[] displays = WifiDisplay.CREATOR.newArray(count);
         for (int i = 0; i < count; i++) {
@@ -441,7 +477,16 @@ final class WifiDisplayController implements DumpUtils.Dump {
         mHandler.post(new Runnable() {
             @Override
             public void run() {
-                mListener.onScanFinished(displays);
+                mListener.onScanResults(displays);
+            }
+        });
+    }
+
+    private void handleScanFinished() {
+        mHandler.post(new Runnable() {
+            @Override
+            public void run() {
+                mListener.onScanFinished();
             }
         });
     }
@@ -484,6 +529,12 @@ final class WifiDisplayController implements DumpUtils.Dump {
             return;
         }
 
+        if (!mWfdEnabled) {
+            Slog.i(TAG, "Ignoring request to connect to Wifi display because the "
+                    +" feature is currently disabled: " + device.deviceName);
+            return;
+        }
+
         mDesiredDevice = device;
         mConnectionRetriesLeft = CONNECT_MAX_RETRIES;
         updateConnection();
@@ -508,6 +559,10 @@ final class WifiDisplayController implements DumpUtils.Dump {
      * connection is established (or not).
      */
     private void updateConnection() {
+        // Step 0. Stop scans if necessary to prevent interference while connected.
+        // Resume scans later when no longer attempting to connect.
+        updateScanState();
+
         // Step 1. Before we try to connect to a new device, tell the system we
         // have disconnected from the old one.
         if (mRemoteDisplay != null && mConnectedDevice != mDesiredDevice) {
@@ -661,7 +716,7 @@ final class WifiDisplayController implements DumpUtils.Dump {
             return; // wait for asynchronous callback
         }
 
-        // Step 6. Listen for incoming connections.
+        // Step 6. Listen for incoming RTSP connection.
         if (mConnectedDevice != null && mRemoteDisplay == null) {
             Inet4Address addr = getInterfaceAddress(mConnectedDeviceGroupInfo);
             if (addr == null) {
@@ -817,7 +872,11 @@ final class WifiDisplayController implements DumpUtils.Dump {
             }
         } else {
             mConnectedDeviceGroupInfo = null;
-            disconnect();
+
+            // Disconnect if we lost the network while connecting or connected to a display.
+            if (mConnectingDevice != null || mConnectedDevice != null) {
+                disconnect();
+            }
 
             // After disconnection for a group, for some reason we have a tendency
             // to get a peer change notification with an empty list of peers.
@@ -828,6 +887,13 @@ final class WifiDisplayController implements DumpUtils.Dump {
         }
     }
 
+    private final Runnable mDiscoverPeers = new Runnable() {
+        @Override
+        public void run() {
+            tryDiscoverPeers();
+        }
+    };
+
     private final Runnable mConnectionTimeout = new Runnable() {
         @Override
         public void run() {
@@ -1033,7 +1099,8 @@ final class WifiDisplayController implements DumpUtils.Dump {
         void onFeatureStateChanged(int featureState);
 
         void onScanStarted();
-        void onScanFinished(WifiDisplay[] availableDisplays);
+        void onScanResults(WifiDisplay[] availableDisplays);
+        void onScanFinished();
 
         void onDisplayConnecting(WifiDisplay display);
         void onDisplayConnectionFailed();