Merge "Allow RSSI Level thresholds to be customized"

7 files changed, 206 insertions, 2 deletions

diff --git a/service/java/com/android/server/wifi/ClientModeImpl.java b/service/java/com/android/server/wifi/ClientModeImpl.java
index d95f6e8be..ddc07f91a 100644
--- a/service/java/com/android/server/wifi/ClientModeImpl.java
+++ b/service/java/com/android/server/wifi/ClientModeImpl.java
@@ -113,6 +113,7 @@ import com.android.server.wifi.proto.nano.WifiMetricsProto.WifiIsUnusableEvent;
 import com.android.server.wifi.proto.nano.WifiMetricsProto.WifiUsabilityStats;
 import com.android.server.wifi.util.ExternalCallbackTracker;
 import com.android.server.wifi.util.NativeUtil;
+import com.android.server.wifi.util.RssiUtil;
 import com.android.server.wifi.util.TelephonyUtil;
 import com.android.server.wifi.util.TelephonyUtil.SimAuthRequestData;
 import com.android.server.wifi.util.TelephonyUtil.SimAuthResponseData;
@@ -2293,7 +2294,7 @@ public class ClientModeImpl extends StateMachine {
              * interested in RSSI of all the changes in signal
              * level.
              */
-            int newSignalLevel = WifiManager.calculateSignalLevel(newRssi, WifiManager.RSSI_LEVELS);
+            int newSignalLevel = RssiUtil.calculateSignalLevel(mContext, newRssi);
             if (newSignalLevel != mLastSignalLevel) {
                 updateCapabilities();
                 sendRssiChangeBroadcast(newRssi);
@@ -2386,7 +2387,7 @@ public class ClientModeImpl extends StateMachine {
     private void sendRssiChangeBroadcast(final int newRssi) {
         mBatteryStatsManager.noteWifiRssiChanged(newRssi);
         StatsLog.write(StatsLog.WIFI_SIGNAL_STRENGTH_CHANGED,
-                WifiManager.calculateSignalLevel(newRssi, WifiManager.RSSI_LEVELS));
+                RssiUtil.calculateSignalLevel(mContext, newRssi));
 
         Intent intent = new Intent(WifiManager.RSSI_CHANGED_ACTION);
         intent.addFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY_BEFORE_BOOT);
diff --git a/service/java/com/android/server/wifi/WifiServiceImpl.java b/service/java/com/android/server/wifi/WifiServiceImpl.java
index 83fb40338..d42735458 100644
--- a/service/java/com/android/server/wifi/WifiServiceImpl.java
+++ b/service/java/com/android/server/wifi/WifiServiceImpl.java
@@ -108,6 +108,7 @@ import com.android.internal.util.AsyncChannel;
 import com.android.server.wifi.hotspot2.PasspointManager;
 import com.android.server.wifi.hotspot2.PasspointProvider;
 import com.android.server.wifi.util.ExternalCallbackTracker;
+import com.android.server.wifi.util.RssiUtil;
 import com.android.server.wifi.util.WifiHandler;
 import com.android.server.wifi.util.WifiPermissionsUtil;
 import com.android.wifi.R;
@@ -3558,4 +3559,9 @@ public class WifiServiceImpl extends BaseWifiService {
                         .unregisterSuggestionConnectionStatusListener(listenerIdentifier,
                                 packageName));
     }
+
+    @Override
+    public int calculateSignalLevel(int rssi) {
+        return RssiUtil.calculateSignalLevel(mContext, rssi);
+    }
 }
diff --git a/service/java/com/android/server/wifi/util/RssiUtil.java b/service/java/com/android/server/wifi/util/RssiUtil.java
new file mode 100644
index 000000000..a1a1d57c2
--- /dev/null
+++ b/service/java/com/android/server/wifi/util/RssiUtil.java
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+package com.android.server.wifi.util;
+
+import android.annotation.NonNull;
+import android.content.Context;
+
+import com.android.wifi.R;
+
+/** Utilities for computations involving RSSI. */
+public class RssiUtil {
+    private RssiUtil() {}
+
+    /** Calculate RSSI level from RSSI using overlaid RSSI level thresholds. */
+    public static int calculateSignalLevel(Context context, int rssi) {
+        int[] thresholds = getRssiLevelThresholds(context);
+
+        for (int level = 0; level < thresholds.length; level++) {
+            if (rssi < thresholds[level]) {
+                return level;
+            }
+        }
+        return thresholds.length;
+    }
+
+    @NonNull
+    private static int[] getRssiLevelThresholds(Context context) {
+        // getIntArray() will never return null, it will throw instead
+        return context.getResources().getIntArray(R.array.config_wifiRssiLevelThresholds);
+    }
+}
diff --git a/service/res/values/config.xml b/service/res/values/config.xml
index 6d595d8d0..ff0befd5b 100644
--- a/service/res/values/config.xml
+++ b/service/res/values/config.xml
@@ -179,4 +179,29 @@
 
     <!-- Indicates that wifi watchdog is enabled on this device -->
     <bool translatable="false" name="config_wifi_watchdog_enabled">true</bool>
+
+    <!--
+    Controls the mapping between RSSI and RSSI levels.
+
+    RSSI                                    RSSI Level
+    (-infinity, thresholds[0])                       0
+    [threshold[0], threshold[1])                     1
+    [threshold[1], threshold[2])                     2
+    ...                                            ...
+    [threshold[len-2], threshold[len-1])         len-1
+    [threshold[len-1], +infinity)                  len
+
+    where:
+        [a, b) is the range of integers `n` such that a <= n < b
+        `threshold[i]` represents the i'th element of the config_wifiRssiLevelThresholds array
+        and `len` is the length of the config_wifiRssiLevelThresholds array.
+    -->
+    <integer-array translatable="false" name="config_wifiRssiLevelThresholds">
+                         <!-- RSSI                RSSI Level -->
+        <item>-88</item> <!-- (-infinity, -88)             0 -->
+        <item>-77</item> <!-- [-88, -77)                   1 -->
+        <item>-66</item> <!-- [-77, -66)                   2 -->
+        <item>-55</item> <!-- [-66, -55)                   3 -->
+                         <!-- [-55, +infinity)             4 -->
+    </integer-array>
 </resources>
diff --git a/service/res/values/overlayable.xml b/service/res/values/overlayable.xml
index 6003e05e7..b7bcad273 100644
--- a/service/res/values/overlayable.xml
+++ b/service/res/values/overlayable.xml
@@ -77,6 +77,7 @@
           <item type="string" name="wifi_localhotspot_configure_ssid_default" />
           <item type="bool" name="config_wifi_diagnostics_bugreport_enabled" />
           <item type="bool" name="config_wifi_watchdog_enabled" />
+          <item type="array" name="config_wifiRssiLevelThresholds" />
           <!-- Params from config.xml that can be overlayed -->
 
           <!-- Params from strings.xml that can be overlayed -->
diff --git a/tests/wifitests/src/com/android/server/wifi/ClientModeImplTest.java b/tests/wifitests/src/com/android/server/wifi/ClientModeImplTest.java
index 51300190a..3f5be9e5c 100644
--- a/tests/wifitests/src/com/android/server/wifi/ClientModeImplTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/ClientModeImplTest.java
@@ -99,6 +99,7 @@ import com.android.server.wifi.proto.nano.WifiMetricsProto;
 import com.android.server.wifi.proto.nano.WifiMetricsProto.StaEvent;
 import com.android.server.wifi.proto.nano.WifiMetricsProto.WifiIsUnusableEvent;
 import com.android.server.wifi.proto.nano.WifiMetricsProto.WifiUsabilityStats;
+import com.android.server.wifi.util.RssiUtilTest;
 import com.android.server.wifi.util.TelephonyUtil;
 import com.android.server.wifi.util.WifiPermissionsUtil;
 import com.android.server.wifi.util.WifiPermissionsWrapper;
@@ -483,6 +484,8 @@ public class ClientModeImplTest extends WifiBaseTest {
 
         mResources = getMockResources();
         mResources.setBoolean(R.bool.config_wifi_connected_mac_randomization_supported, true);
+        mResources.setIntArray(R.array.config_wifiRssiLevelThresholds,
+                RssiUtilTest.RSSI_THRESHOLDS);
         when(mContext.getResources()).thenReturn(mResources);
 
         when(mFrameworkFacade.getIntegerSetting(mContext,
diff --git a/tests/wifitests/src/com/android/server/wifi/util/RssiUtilTest.java b/tests/wifitests/src/com/android/server/wifi/util/RssiUtilTest.java
new file mode 100644
index 000000000..cebf83766
--- /dev/null
+++ b/tests/wifitests/src/com/android/server/wifi/util/RssiUtilTest.java
@@ -0,0 +1,124 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+package com.android.server.wifi.util;
+
+import static com.google.common.truth.Truth.assertThat;
+import static com.google.common.truth.Truth.assertWithMessage;
+
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import android.content.Context;
+import android.content.pm.ApplicationInfo;
+import android.content.res.Resources;
+import android.net.wifi.IWifiManager;
+import android.net.wifi.WifiManager;
+import android.os.Build;
+import android.os.Looper;
+
+import androidx.test.filters.SmallTest;
+
+import com.android.server.wifi.WifiBaseTest;
+import com.android.wifi.R;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+
+/** Unit tests for {@link RssiUtil}. */
+@SmallTest
+public class RssiUtilTest extends WifiBaseTest {
+
+    public static final int[] RSSI_THRESHOLDS = {-88, -77, -66, -55};
+
+    @Mock private Context mContext;
+    @Mock private Resources mResources;
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        when(mContext.getResources()).thenReturn(mResources);
+        when(mResources.getIntArray(R.array.config_wifiRssiLevelThresholds))
+                .thenReturn(RSSI_THRESHOLDS);
+    }
+
+    /**
+     * Tests that our default RSSI thresholds matches what would be calculated by
+     * {@link WifiManager#calculateSignalLevel(int, int)}.
+     */
+    @Test
+    public void testCalculateSignalLevelImplementationsConsistent() {
+        for (int rssi = -100; rssi <= 0; rssi++) {
+            int expected = WifiManager.calculateSignalLevel(rssi, WifiManager.RSSI_LEVELS);
+            int actual = RssiUtil.calculateSignalLevel(mContext, rssi);
+            assertWithMessage("RSSI: %s", rssi).that(actual).isEqualTo(expected);
+        }
+    }
+
+    /** Tests the signal level at RSSIs at around the thresholds. */
+    @Test
+    public void testCalculateSignalLevel() {
+        assertThat(RssiUtil.calculateSignalLevel(mContext, -100)).isEqualTo(0);
+        assertThat(RssiUtil.calculateSignalLevel(mContext, -89)).isEqualTo(0);
+        assertThat(RssiUtil.calculateSignalLevel(mContext, -88)).isEqualTo(1);
+        assertThat(RssiUtil.calculateSignalLevel(mContext, -78)).isEqualTo(1);
+        assertThat(RssiUtil.calculateSignalLevel(mContext, -77)).isEqualTo(2);
+        assertThat(RssiUtil.calculateSignalLevel(mContext, -67)).isEqualTo(2);
+        assertThat(RssiUtil.calculateSignalLevel(mContext, -66)).isEqualTo(3);
+        assertThat(RssiUtil.calculateSignalLevel(mContext, -56)).isEqualTo(3);
+        assertThat(RssiUtil.calculateSignalLevel(mContext, -55)).isEqualTo(4);
+        assertThat(RssiUtil.calculateSignalLevel(mContext, 0)).isEqualTo(4);
+        assertThat(RssiUtil.calculateSignalLevel(mContext, Integer.MAX_VALUE)).isEqualTo(4);
+    }
+
+    /** Tests that an empty thresholds array always returns level 0. */
+    @Test
+    public void testCalculateSignalLevelEmptyThresholdsArray() {
+        when(mResources.getIntArray(R.array.config_wifiRssiLevelThresholds))
+                .thenReturn(new int[0]);
+        assertThat(RssiUtil.calculateSignalLevel(mContext, -100)).isEqualTo(0);
+        assertThat(RssiUtil.calculateSignalLevel(mContext, -50)).isEqualTo(0);
+        assertThat(RssiUtil.calculateSignalLevel(mContext, 0)).isEqualTo(0);
+
+        assertThat(RssiUtil.calculateSignalLevel(mContext, Integer.MAX_VALUE)).isEqualTo(0);
+    }
+
+    /** Tests that the expected default max signal level is returned. */
+    @Test
+    public void testGetMaxSignalLevel() throws Exception {
+        IWifiManager iWifiManager = mock(IWifiManager.class);
+
+        doAnswer(invocation -> {
+            int rssi = invocation.getArgument(0);
+            return RssiUtil.calculateSignalLevel(mContext, rssi);
+        }).when(iWifiManager).calculateSignalLevel(anyInt());
+
+        ApplicationInfo applicationInfo = mock(ApplicationInfo.class);
+        applicationInfo.targetSdkVersion = Build.VERSION_CODES.Q;
+        Context context = mock(Context.class);
+        when(context.getApplicationInfo()).thenReturn(applicationInfo);
+        when(context.getOpPackageName()).thenReturn("TestPackage");
+        WifiManager wifiManager = new WifiManager(
+                context, iWifiManager, mock(Looper.class));
+
+        int level = wifiManager.getMaxSignalLevel();
+        assertThat(level).isEqualTo(4);
+    }
+}