学步园

    open_devnull_stdio();
    log_init();
    
    INFO("reading config file\n");
    init_parse_config_file("/init.rc");

    /* pull the kernel commandline and ramdisk properties file in */
    import_kernel_cmdline(0);

    get_hardware_name(hardware, &revision);
    snprintf(tmp, sizeof(tmp), "/init.%s.rc", hardware);
    init_parse_config_file(tmp);

service servicemanager /system/bin/servicemanager
    user system
    critical
    onrestart restart zygote
    onrestart restart media

service vold /system/bin/vold
    socket vold stream 0660 root mount
    ioprio be 2

service netd /system/bin/netd
    socket netd stream 0660 root system
    socket dnsproxyd stream 0660 root inet

service debuggerd /system/bin/debuggerd

service ril-daemon /system/bin/rild
    socket rild stream 660 root radio
    socket rild-debug stream 660 radio system
    user root
    group radio cache inet misc audio sdcard_rw

service zygote /system/bin/app_process -Xzygote /system/bin --zygote --start-system-server
    socket zygote stream 666
    onrestart write /sys/android_power/request_state wake
    onrestart write /sys/power/state on
    onrestart restart media
    onrestart restart netd

service drm /system/bin/drmserver
    user drm
    group system root inet

        execute_one_command();
        restart_processes()

int main(int argc, char**argv)
{
    struct binder_state *bs;
    void*svcmgr = BINDER_SERVICE_MANAGER;

    bs = binder_open(128*1024);

    if (binder_become_context_manager(bs)) {
        LOGE("cannot become context manager (%s)\n", strerror(errno));
        return-1;
    }

    svcmgr_handle = svcmgr;
    binder_loop(bs, svcmgr_handler);
    return0;
}

int binder_become_context_manager(struct binder_state *bs)
{
    return ioctl(bs->fd, BINDER_SET_CONTEXT_MGR, 0);
}

if (0== strcmp("--zygote", arg)) {
            bool startSystemServer = (i < argc) ? 
                    strcmp(argv[i], "--start-system-server") ==0 : false;
            setArgv0(argv0, "zygote");
            set_process_name("zygote");
            runtime.start("com.android.internal.os.ZygoteInit",
                startSystemServer);
        } else {
            set_process_name(argv0);

            runtime.mClassName = arg;

            // Remainder of args get passed to startup class main()
            runtime.mArgC = argc-i;
            runtime.mArgV = argv+i;

            LOGV("App process is starting with pid=%d, class=%s.\n",
                 getpid(), runtime.getClassName());
            runtime.start();
        }

            registerZygoteSocket();
            EventLog.writeEvent(LOG_BOOT_PROGRESS_PRELOAD_START,
                SystemClock.uptimeMillis());
            preloadClasses();
            //cacheRegisterMaps();
            preloadResources();
            EventLog.writeEvent(LOG_BOOT_PROGRESS_PRELOAD_END,
                SystemClock.uptimeMillis());

            // Finish profiling the zygote initialization.
            SamplingProfilerIntegration.writeZygoteSnapshot();

            // Do an initial gc to clean up after startup
            gc();

            // If requested, start system server directly from Zygote
if (argv.length !=2) {
                thrownew RuntimeException(argv[0] + USAGE_STRING);
            }

            if (argv[1].equals("true")) {
                startSystemServer();
            } elseif (!argv[1].equals("false")) {
                thrownew RuntimeException(argv[0] + USAGE_STRING);
            }

// Preload classes that were loaded by at least 2 processes. Hopefully,
        // the memory associated with these classes will be shared.
for (LoadedClass loadedClass : root.loadedClasses.values()) {
            Set<String> names = loadedClass.processNames();
            if (!Policy.isPreloadable(loadedClass)) {
                continue;
            }

            if (names.size() >= MIN_PROCESSES ||
                    (loadedClass.medianTimeMicros() > MIN_LOAD_TIME_MICROS && names.size() >1)) {
                toPreload.add(loadedClass);
            }
        }

        int initialSize = toPreload.size();
        System.out.println(initialSize
                +" classses were loaded by more than one app.");

        // Preload eligable classes from applications (not long-running
        // services).
for (Proc proc : root.processes.values()) {
            if (proc.fromZygote() &&!Policy.isService(proc.name)) {
                for (Operation operation : proc.operations) {
                    LoadedClass loadedClass = operation.loadedClass;
                    if (shouldPreload(loadedClass)) {
                        toPreload.add(loadedClass);
                    }
                }
            }
        }

/**Reports if the given class should be preloaded. */
    publicstatic boolean isPreloadable(LoadedClass clazz) {
        return clazz.systemClass &&!EXCLUDED_CLASSES.contains(clazz.name);
    }

/**
     * Classes which we shouldn't load from the Zygote.
     */
    privatestatic final Set<String> EXCLUDED_CLASSES
            =new HashSet<String>(Arrays.asList(
        // Binders
"android.app.AlarmManager",
        "android.app.SearchManager",
        "android.os.FileObserver",
        "com.android.server.PackageManagerService$AppDirObserver",

        // Threads
"android.os.AsyncTask",
        "android.pim.ContactsAsyncHelper",
        "java.lang.ProcessManager"
    ));

/**
     * Long running services. These are restricted in their contribution to the 
     * preloader because their launch time is less critical.
     */
    // TODO: Generate this automatically from package manager.
privatestatic final Set<String> SERVICES =new HashSet<String>(Arrays.asList(
        "system_server",
        "com.google.process.content",
        "android.process.media",
        "com.android.bluetooth",
        "com.android.calendar",
        "com.android.inputmethod.latin",
        "com.android.phone",
        "com.google.android.apps.maps.FriendService", // pre froyo
"com.google.android.apps.maps:FriendService", // froyo
"com.google.android.apps.maps.LocationFriendService",
        "com.google.android.deskclock",
        "com.google.process.gapps",
        "android.tts"
    ));

/* Hardcoded command line to start the system server */
        String args[] = {
            "--setuid=1000",
            "--setgid=1000",
            "--setgroups=1001,1002,1003,1004,1005,1006,1007,1008,1009,1010,1018,3001,3002,3003",
            "--capabilities=130104352,130104352",
            "--runtime-init",
            "--nice-name=system_server",
            "com.android.server.SystemServer",
        };
        ZygoteConnection.Arguments parsedArgs =null;

        int pid;

        try {
            parsedArgs =new ZygoteConnection.Arguments(args);

            /*
             * Enable debugging of the system process if *either* the command line flags
             * indicate it should be debuggable or the ro.debuggable system property
             * is set to "1"
             */
            int debugFlags = parsedArgs.debugFlags;
            if ("1".equals(SystemProperties.get("ro.debuggable")))
                debugFlags |= Zygote.DEBUG_ENABLE_DEBUGGER;

            /* Request to fork the system server process */
            pid = Zygote.forkSystemServer(
                    parsedArgs.uid, parsedArgs.gid,
                    parsedArgs.gids, debugFlags, null,
                    parsedArgs.permittedCapabilities,
                    parsedArgs.effectiveCapabilities)

// The system server has to run all of the time, so it needs to be
        // as efficient as possible with its memory usage.
        VMRuntime.getRuntime().setTargetHeapUtilization(0.8f);
        
        System.loadLibrary("android_servers");
        init1(args);

staticvoid android_server_SystemServer_init1(JNIEnv* env, jobject clazz)
{
    system_init();
}

// Start the sensor service
    SensorService::instantiate();

    // On the simulator, audioflinger et al don't get started the
    // same way as on the device, and we need to start them here
if (!proc->supportsProcesses()) {

        // Start the AudioFlinger
        AudioFlinger::instantiate();

        // Start the media playback service
        MediaPlayerService::instantiate();

        // Start the camera service
        CameraService::instantiate();

        // Start the audio policy service
        AudioPolicyService::instantiate();
    }

    LOGI("System server: starting Android services.\n");
    runtime->callStatic("com/android/server/SystemServer", "init2");

publicstatic final void init2() {
        Slog.i(TAG, "Entered the Android system server!");
        Thread thr =new ServerThread();
        thr.setName("android.server.ServerThread");
        thr.start();
    }

            Slog.i(TAG, "Content Manager");
            ContentService.main(context,
                    factoryTest == SystemServer.FACTORY_TEST_LOW_LEVEL);

            Slog.i(TAG, "System Content Providers");
            ActivityManagerService.installSystemProviders();

            Slog.i(TAG, "Battery Service");
            battery =new BatteryService(context);
            ServiceManager.addService("battery", battery);

            Slog.i(TAG, "Lights Service");
            lights =new LightsService(context);

            Slog.i(TAG, "Vibrator Service");
            ServiceManager.addService("vibrator", new VibratorService(context));

            // only initialize the power service after we have started the
            // lights service, content providers and the battery service.
            power.init(context, lights, ActivityManagerService.getDefault(), battery);

            Slog.i(TAG, "Alarm Manager");
            AlarmManagerService alarm =new AlarmManagerService(context);
            ServiceManager.addService(Context.ALARM_SERVICE, alarm);

            ((ActivityManagerService)ServiceManager.getService("activity"))
                    .setWindowManager(wm);

            // Skip Bluetooth if we have an emulator kernel
            // TODO: Use a more reliable check to see if this product should
            // support Bluetooth - see bug 988521
if (SystemProperties.get("ro.kernel.qemu").equals("1")) {
                Slog.i(TAG, "Registering null Bluetooth Service (emulator)");
                ServiceManager.addService(BluetoothAdapter.BLUETOOTH_SERVICE, null);
            } elseif (factoryTest == SystemServer.FACTORY_TEST_LOW_LEVEL) {
                Slog.i(TAG, "Registering null Bluetooth Service (factory test)");
                ServiceManager.addService(BluetoothAdapter.BLUETOOTH_SERVICE, null);
            } else {
                Slog.i(TAG, "Bluetooth Service");
                bluetooth =new BluetoothService(context);
                ServiceManager.addService(BluetoothAdapter.BLUETOOTH_SERVICE, bluetooth);
                bluetooth.initAfterRegistration();
                bluetoothA2dp =new BluetoothA2dpService(context, bluetooth);
                ServiceManager.addService(BluetoothA2dpService.BLUETOOTH_A2DP_SERVICE,
                                          bluetoothA2dp);

                int bluetoothOn = Settings.Secure.getInt(mContentResolver,
                    Settings.Secure.BLUETOOTH_ON, 0);
                if (bluetoothOn >0) {
                    bluetooth.enable();
                }
            }

            mMainStack.resumeTopActivityLocked(null);

// Find the first activity that is not finishing.
        ActivityRecord next = topRunningActivityLocked(null);

        // Remember how we'll process this pause/resume situation, and ensure
        // that the state is reset however we wind up proceeding.
        final boolean userLeaving = mUserLeaving;
        mUserLeaving =false;

        if (next ==null) {
            // There are no more activities!  Let's just start up the
            // Launcher...
if (mMainStack) {
                return mService.startHomeActivityLocked();
            }
        }

        Intent intent =new Intent(
            mTopAction,
            mTopData !=null? Uri.parse(mTopData) : null);
        intent.setComponent(mTopComponent);
        if (mFactoryTest != SystemServer.FACTORY_TEST_LOW_LEVEL) {
            intent.addCategory(Intent.CATEGORY_HOME);
        }