ExternalScoreEvaluator: factor in active network

When obtaining the score for an externally scored network, indicate
whether the network is the currently connected one, which is
favored by the external scorer. This helps avoid unnecessary
roaming caused by RSSI fluctuation.

Bug: 31928897
Test: Wifi framework unit tests
Change-Id: I4a0657de58f4dab3fc5e004082dcf5d7c4a02e31

2 files changed, 84 insertions, 6 deletions

diff --git a/tests/wifitests/src/com/android/server/wifi/ExternalScoreEvaluatorTest.java b/tests/wifitests/src/com/android/server/wifi/ExternalScoreEvaluatorTest.java
index 16bd4f8d8..ada21461f 100644
--- a/tests/wifitests/src/com/android/server/wifi/ExternalScoreEvaluatorTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/ExternalScoreEvaluatorTest.java
@@ -416,4 +416,75 @@ public class ExternalScoreEvaluatorTest {
 
         assertEquals("Expect null configuration", null, candidate);
     }
+
+    /**
+     * Between two ephemeral networks with the same RSSI, choose
+     * the currently connected one.
+     */
+    @Test
+    public void chooseActiveEphemeralNetwork() {
+        String[] ssids = {"\"test1\"", "\"test2\""};
+        String[] bssids = {"6c:f3:7f:ae:8c:f3", "6c:f3:7f:ae:8c:f4"};
+        int[] freqs = {2470, 2437};
+        String[] caps = {"[ESS]", "[ESS]"};
+        int[] levels = {mThresholdQualifiedRssi2G + 28, mThresholdQualifiedRssi2G + 28};
+        boolean[] meteredHints = {true, true};
+        ScanResult[] scanResults = new ScanResult[2];
+        WifiConfiguration[] ephemeralNetworkConfigs = new WifiConfiguration[2];
+
+        List<ScanDetail> scanDetails = WifiNetworkSelectorTestUtil.buildScanDetails(
+                    ssids, bssids, freqs, caps, levels, mClock);
+        WifiNetworkSelectorTestUtil.configureScoreCache(mScoreCache,
+                    scanDetails, null, meteredHints);
+
+        // No saved networks.
+        when(mWifiConfigManager.getSavedNetworkForScanDetailAndCache(any(ScanDetail.class)))
+                .thenReturn(null);
+
+        for (int i = 0; i < 2; i++) {
+            scanResults[i] = scanDetails.get(i).getScanResult();
+            ephemeralNetworkConfigs[i] = WifiNetworkSelectorTestUtil
+                .setupEphemeralNetwork(mWifiConfigManager, i, scanResults[i], meteredHints[i]);
+        }
+
+        WifiConfiguration candidate = mExternalScoreEvaluator.evaluateNetworks(scanDetails,
+                null, bssids[1], true, true, null);
+
+        WifiConfigurationTestUtil.assertConfigurationEqual(ephemeralNetworkConfigs[1], candidate);
+        WifiNetworkSelectorTestUtil.verifySelectedScanResult(mWifiConfigManager,
+                scanResults[1], candidate);
+        assertEquals(meteredHints[1], candidate.meteredHint);
+    }
+
+    /**
+     *  Between two externally scored saved networks with the same RSSI, choose
+     *  the currently connected one.
+     */
+    @Test
+    public void chooseActiveSavedNetwork() {
+        String[] ssids = {"\"test1\"", "\"test2\""};
+        String[] bssids = {"6c:f3:7f:ae:8c:f3", "6c:f3:7f:ae:8c:f4"};
+        int[] freqs = {2470, 2437};
+        String[] caps = {"[WPA2-EAP-CCMP][ESS]", "[WPA2-EAP-CCMP][ESS]"};
+        int[] securities = {SECURITY_PSK, SECURITY_PSK};
+        int[] levels = {mThresholdQualifiedRssi2G + 28, mThresholdQualifiedRssi2G + 28};
+        boolean[] meteredHints = {false, false};
+
+        ScanDetailsAndWifiConfigs scanDetailsAndConfigs =
+                WifiNetworkSelectorTestUtil.setupScanDetailsAndConfigStore(ssids, bssids,
+                    freqs, caps, levels, securities, mWifiConfigManager, mClock);
+        List<ScanDetail> scanDetails = scanDetailsAndConfigs.getScanDetails();
+        WifiConfiguration[] savedConfigs = scanDetailsAndConfigs.getWifiConfigs();
+        savedConfigs[0].useExternalScores = savedConfigs[1].useExternalScores = true;
+
+        WifiNetworkSelectorTestUtil.configureScoreCache(mScoreCache,
+                    scanDetails, null, meteredHints);
+
+        WifiConfiguration candidate = mExternalScoreEvaluator.evaluateNetworks(scanDetails,
+                savedConfigs[1], bssids[1], true, true, null);
+
+        WifiConfigurationTestUtil.assertConfigurationEqual(savedConfigs[1], candidate);
+        WifiNetworkSelectorTestUtil.verifySelectedScanResult(mWifiConfigManager,
+                scanDetails.get(1).getScanResult(), candidate);
+    }
 }
diff --git a/tests/wifitests/src/com/android/server/wifi/WifiNetworkSelectorTestUtil.java b/tests/wifitests/src/com/android/server/wifi/WifiNetworkSelectorTestUtil.java
index db3aff14c..e01af28b1 100644
--- a/tests/wifitests/src/com/android/server/wifi/WifiNetworkSelectorTestUtil.java
+++ b/tests/wifitests/src/com/android/server/wifi/WifiNetworkSelectorTestUtil.java
@@ -309,17 +309,24 @@ public class WifiNetworkSelectorTestUtil {
 
         for (int i = 0; i < scanDetails.size(); i++) {
             ScanDetail scanDetail = scanDetails.get(i);
-            byte rssiScore;
-            Integer score = scores[i];
             ScanResult scanResult = scanDetail.getScanResult();
             WifiKey wifiKey = new WifiKey("\"" + scanResult.SSID + "\"", scanResult.BSSID);
             NetworkKey ntwkKey = new NetworkKey(wifiKey);
-            if (scores[i] == null) {
-                rssiScore = WifiNetworkScoreCache.INVALID_NETWORK_SCORE;
+            RssiCurve rssiCurve;
+
+            if (scores != null) { // fixed score
+                byte rssiScore;
+                Integer score = scores[i];
+
+                if (scores[i] == null) {
+                    rssiScore = WifiNetworkScoreCache.INVALID_NETWORK_SCORE;
+                } else {
+                    rssiScore = scores[i].byteValue();
+                }
+                rssiCurve = new RssiCurve(-100, 100, new byte[] {rssiScore});
             } else {
-                rssiScore = scores[i].byteValue();
+                rssiCurve = new RssiCurve(-80, 20, new byte[] {-10, 0, 10, 20, 30, 40});
             }
-            RssiCurve rssiCurve = new RssiCurve(-100, 100, new byte[] {rssiScore});
             ScoredNetwork scoredNetwork = new ScoredNetwork(ntwkKey, rssiCurve, meteredHints[i]);
 
             networks.add(scoredNetwork);