Wifi country code refactoring

This CL pulls coutry code logic into one class.
This also refactors all the existing country code logic.
We do not set country code for P2p interface now because
this is redundant. wpa_supplicant will route all the request
to the real interface.
Some initial unittests are added.

Bug: 27477896
TEST: compile, runtest frameworks-wifi,
      manually tested with an angler phone
Change-Id: I870c3ad615a1f9bfb3fb40b149b9ca71dc850cdd

1 files changed, 186 insertions, 0 deletions

diff --git a/service/java/com/android/server/wifi/WifiCountryCode.java b/service/java/com/android/server/wifi/WifiCountryCode.java
new file mode 100644
index 000000000..8136eeb7d
--- /dev/null
+++ b/service/java/com/android/server/wifi/WifiCountryCode.java
@@ -0,0 +1,186 @@
+/*
+ * Copyright (C) 2016 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;
+
+import android.text.TextUtils;
+import android.util.Log;
+
+/**
+ * Provide functions for making changes to WiFi country code.
+ */
+public class WifiCountryCode {
+    private static final String TAG = "WifiCountryCode";
+    private final WifiNative mWifiNative;
+    private boolean DBG = false;
+    private boolean mReady = false;
+
+    /** config option that indicate whether or not to reset country code to default when
+     * cellular radio indicates country code loss
+     */
+    private boolean mRevertCountryCodeOnCellularLoss;
+    private String mDefaultCountryCode = null;
+    private String mTelephonyCountryCode = null;
+    private String mCurrentCountryCode = null;
+
+    public WifiCountryCode(WifiNative wifiNative, String defaultCountryCode,
+            boolean revertCountryCodeOnCellularLoss) {
+        mWifiNative = wifiNative;
+        mRevertCountryCodeOnCellularLoss = revertCountryCodeOnCellularLoss;
+
+        if (!TextUtils.isEmpty(defaultCountryCode)) {
+            mDefaultCountryCode = defaultCountryCode;
+            mDefaultCountryCode = mDefaultCountryCode.toUpperCase();
+        } else {
+            if (mRevertCountryCodeOnCellularLoss) {
+                Log.w(TAG, "config_wifi_revert_country_code_on_cellular_loss is set, "
+                         + "but there is no default country code.");
+                mRevertCountryCodeOnCellularLoss = false;
+                return;
+            }
+        }
+
+        if (mRevertCountryCodeOnCellularLoss) {
+            Log.d(TAG, "Country code will be reverted to " + mDefaultCountryCode
+                    + " on MCC loss");
+        }
+    }
+
+    /**
+     * Enable verbose logging for WifiCountryCode.
+     */
+    public void enableVerboseLogging(int verbose) {
+        if (verbose > 0) {
+            DBG = true;
+        } else {
+            DBG = false;
+        }
+    }
+
+    /**
+     * This is called when sim card is removed.
+     * In this case we should invalid all other country codes except the
+     * phone default one.
+     */
+    public synchronized void simCardRemoved() {
+        if (DBG) Log.d(TAG, "SIM Card Removed");
+        // SIM card is removed, we need to reset the country code to phone default.
+        if (mRevertCountryCodeOnCellularLoss) {
+            mTelephonyCountryCode = null;
+            if (mReady) {
+                updateCountryCode();
+            }
+        }
+    }
+
+    /**
+     * This is called when airplane mode is enabled.
+     * In this case we should invalidate all other country code except the
+     * phone default one.
+     */
+    public synchronized void airplaneModeEnabled() {
+        if (DBG) Log.d(TAG, "Airplane Mode Enabled");
+        mTelephonyCountryCode = null;
+        // Airplane mode is enabled, we need to reset the country code to phone default.
+        if (mRevertCountryCodeOnCellularLoss) {
+            mTelephonyCountryCode = null;
+            // Country code will be set upon when wpa_supplicant starts next time.
+        }
+    }
+
+    /**
+     * Change the state to indicates if wpa_supplicant is ready to handle country code changing
+     * request or not.
+     * We call native code to request country code changes only when wpa_supplicant is
+     * started but not yet L2 connected.
+     */
+    public synchronized void setReadyForChange(boolean ready) {
+        if (DBG) Log.d(TAG, "Set ready: " + ready);
+        mReady = ready;
+        // We are ready to set country code now.
+        // We need to post pending country code request.
+        if (mReady) {
+            updateCountryCode();
+        }
+    }
+
+    /**
+     * Handle country code change request.
+     * @param countryCode The country code intended to set.
+     * This is supposed to be from Telephony service.
+     * otherwise we think it is from other applications.
+     */
+    public synchronized void setCountryCode(String countryCode) {
+        if (DBG) Log.d(TAG, "Receive set country code request: " + countryCode);
+        // Ignore empty country code.
+        if (countryCode.length() == 0) {
+            if (DBG) Log.d(TAG, "Ignore empty country code");
+            return;
+        }
+        mTelephonyCountryCode = countryCode;
+        mTelephonyCountryCode.toUpperCase();
+        // If wpa_supplicant is ready we set the country code now, otherwise it will be
+        // set once wpa_supplicant is ready.
+        if (mReady) {
+            updateCountryCode();
+        }
+    }
+
+    /**
+     * @return Get the current country code, returns null if no country code is set.
+     */
+    public synchronized String getCurrentCountryCode() {
+        return mCurrentCountryCode;
+    }
+
+    private void updateCountryCode() {
+        if (DBG) Log.d(TAG, "Update country code");
+        String country = pickCountryCode();
+        // We do not check if the country code equals the current one.
+        // There are two reasons:
+        // 1. Wpa supplicant may silently modify the country code.
+        // 2. If Wifi restarted therefoere wpa_supplicant also restarted,
+        // the country code counld be reset to '00' by wpa_supplicant.
+        if (country.length() != 0) {
+            setCountryCodeNative(country);
+        }
+        // We do not set country code if there is no candidate. This is reasonable
+        // because wpa_supplicant usually starts with an international safe country
+        // code setting: '00'.
+    }
+
+    private String pickCountryCode() {
+        if (mTelephonyCountryCode != null) {
+            return mTelephonyCountryCode;
+        }
+        if (mDefaultCountryCode != null) {
+            return mDefaultCountryCode;
+        }
+        // If there is no candidate country code we will return an empty string.
+        return "";
+    }
+
+    private boolean setCountryCodeNative(String country) {
+        if (mWifiNative.setCountryCode(country)) {
+            Log.d(TAG, "Succeeded to set country code to: " + country);
+            mCurrentCountryCode = country;
+            return true;
+        }
+        Log.d(TAG, "Failed to set country code to: " + country);
+        return false;
+    }
+}
+