Merge "Fix CtsTetheringTest on devices without permanent softAp interfaces."

tests/cts/tethering/src/android/tethering/cts/TetheringManagerTest.java

@@ -57,8 +57,11 @@ import android.net.TetheringManager.TetheringInterfaceRegexps;
 import android.net.TetheringManager.TetheringRequest;
 import android.net.cts.util.CtsNetUtils;
 import android.net.cts.util.CtsNetUtils.TestNetworkCallback;
+import android.net.wifi.WifiClient;
 import android.net.wifi.WifiManager;
+import android.net.wifi.WifiManager.SoftApCallback;
 import android.os.Bundle;
+import android.os.ConditionVariable;
 import android.os.PersistableBundle;
 import android.os.ResultReceiver;
 import android.telephony.CarrierConfigManager;
@@ -135,6 +138,40 @@ public class TetheringManagerTest {
         dropShellPermissionIdentity();
     }
 
+    private static class StopSoftApCallback implements SoftApCallback {
+        private final ConditionVariable mWaiting = new ConditionVariable();
+        @Override
+        public void onStateChanged(int state, int failureReason) {
+            if (state == WifiManager.WIFI_AP_STATE_DISABLED) mWaiting.open();
+        }
+
+        @Override
+        public void onConnectedClientsChanged(List<WifiClient> clients) { }
+
+        public void waitForSoftApStopped() {
+            if (!mWaiting.block(DEFAULT_TIMEOUT_MS)) {
+                fail("stopSoftAp Timeout");
+            }
+        }
+    }
+
+    // Wait for softAp to be disabled. This is necessary on devices where stopping softAp
+    // deletes the interface. On these devices, tethering immediately stops when the softAp
+    // interface is removed, but softAp is not yet fully disabled. Wait for softAp to be
+    // fully disabled, because otherwise the next test might fail because it attempts to
+    // start softAp before it's fully stopped.
+    private void expectSoftApDisabled() {
+        final StopSoftApCallback callback = new StopSoftApCallback();
+        try {
+            mWm.registerSoftApCallback(c -> c.run(), callback);
+            // registerSoftApCallback will immediately call the callback with the current state, so
+            // this callback will fire even if softAp is already disabled.
+            callback.waitForSoftApStopped();
+        } finally {
+            mWm.unregisterSoftApCallback(callback);
+        }
+    }
+
     private class TetherChangeReceiver extends BroadcastReceiver {
         private class TetherState {
             final ArrayList<String> mAvailable;
@@ -294,6 +331,7 @@ public class TetheringManagerTest {
         mTetherChangeReceiver.expectTethering(true /* active */, wifiRegexs);
 
         mTM.stopTethering(TETHERING_WIFI);
+        expectSoftApDisabled();
         mTetherChangeReceiver.expectTethering(false /* active */, wifiRegexs);
     }
 
@@ -544,6 +582,7 @@ public class TetheringManagerTest {
 
     private void stopWifiTethering(final TestTetheringEventCallback callback) {
         mTM.stopTethering(TETHERING_WIFI);
+        expectSoftApDisabled();
         callback.expectTetheredInterfacesChanged(null);
         callback.expectOneOfOffloadStatusChanged(TETHER_HARDWARE_OFFLOAD_STOPPED);
     }