Android - Wifi 初始化過程

一張簡圖就是最基本的初始化過程啦!

稍微描述如下列各項:

1) 透過 new WifiService(context) 開啟wifi的服務, 也透過ConnectivityService() 開啟 connectivity服務
位置: android/frameworks/base/services/java/com/android/server/SystemServer.java

               try {                    Slog.i(TAG, "Wi-Fi Service");                    wifi = new WifiService(context);                    ServiceManager.addService(Context.WIFI_SERVICE, wifi);                } catch (Throwable e) {                    reportWtf("starting Wi-Fi Service", e);                }               try {                   int enableCne = 1;                   if (!deviceHasSufficientMemory()) {                       enableCne = SystemProperties.getInt("persist.cne.override.memlimit", 0);                   }                   int cneFeature = (enableCne == 1) ?                       SystemProperties.getInt("persist.cne.feature", 0) : 0;                   if ( cneFeature > 0 && cneFeature < 10 ) {                       Slog.i(TAG, "QcConnectivity Service");                       PathClassLoader qcsClassLoader =                           new PathClassLoader("/system/framework/services-ext.jar",                                   ClassLoader.getSystemClassLoader());                       Class qcsClass =                           qcsClassLoader.loadClass("com.android.server.QcConnectivityService");                       Constructor qcsConstructor = qcsClass.getConstructor                           (new Class[] {Context.class, INetworkManagementService.class,                            INetworkStatsService.class, INetworkPolicyManager.class});                       qcCon = qcsConstructor.newInstance(                               context, networkManagement, networkStats, networkPolicy);                       connectivity = (ConnectivityService) qcCon;                   } else {                       Slog.i(TAG, "Connectivity Service");                       connectivity = new ConnectivityService( context, networkManagement,                               networkStats, networkPolicy);                   }                   if (connectivity != null) {                       ServiceManager.addService(Context.CONNECTIVITY_SERVICE, connectivity);                       networkStats.bindConnectivityManager(connectivity);                       networkPolicy.bindConnectivityManager(connectivity);                       wifi.checkAndStartWifi();                       wifiP2p.connectivityServiceReady();                   }               } catch (Throwable e) {                   reportWtf("starting Connectivity Service", e);               }

2) 由第一項SystemServer.java裡呼叫 WifiService()定義
位置: android/frameworks/base/services/java/com/android/server/wifi

/** * WifiService handles remote WiFi operation requests by implementing * the IWifiManager interface. * * @hide */public final class WifiService extends IWifiManager.Stub {    private static final String TAG = "WifiService";    private static final boolean DBG = false;    final WifiStateMachine mWifiStateMachine;    private final Context mContext;   ....

3) 由第一項SystemServer.java裡呼叫 ConnectivityService()
位置: android/frameworks/base/services/java/com/android/server/ConnectivityService.java

/** * @hide */public class ConnectivityService extends IConnectivityManager.Stub {    private static final String TAG = "ConnectivityService";    protected static final boolean DBG = true;    protected static final boolean VDBG = false;    protected static final boolean LOGD_RULES = false;    ...

4) 由第三項ConnectivityService.java裡呼叫 WifiStateTracker()
位置: android/frameworks/base/services/java/com/android/server/wifi/WifiStateTracker

    public WifiStateTracker(int netType, String networkName) {        mNetworkInfo = new NetworkInfo(netType, 0, networkName, "");        mLinkProperties = new LinkProperties();        mLinkCapabilities = new LinkCapabilities();        mNetworkInfo.setIsAvailable(false);        setTeardownRequested(false);    }

以上的話, 大致wifi的初始化ok