Android关机流程解析

在PowerManager的API文档中，给出了一个关机/重启接口：

public void reboot (String reason)
对于这个接口的描述很简单，就是几句话。

接口的作用就是重启设备，而且，就算重启成功了也没有返回值。

需要包含REBOOT权限，也就是android.permission.REBOOT

唯一参数reason代表需要的特定重启模式，比如recovery，当然也可以为null。

--------------------------------上层空间--------------------------------

1.frameworks/base/core/java/android/os/PowerManager.java

[java]
* Reboot the device. Will not return if the reboot is
* successful. Requires the {@link android.Manifest.permission#REBOOT}
* permission.
*
* @param reason code to pass to the kernel (e.g., "recovery") to
*               request special boot modes, or null.
*/
public void reboot(String reason)
{
    try {
        mService.reboot(reason);
    } catch (RemoteException e) {
    }
}

    /**
     * Reboot the device. Will not return if the reboot is
     * successful. Requires the {@link android.Manifest.permission#REBOOT}
     * permission.
     *
     * @param reason code to pass to the kernel (e.g., "recovery") to
     *               request special boot modes, or null.
     */
    public void reboot(String reason)
    {
        try {
            mService.reboot(reason);
        } catch (RemoteException e) {
        }
    }
mService为IPowerManager Binder接口服务。

[java]
/**
* {@hide}
*/
public PowerManager(IPowerManager service, Handler handler)
{
mService = service;
mHandler = handler;
}

    /**
     * {@hide}
     */
    public PowerManager(IPowerManager service, Handler handler)
    {
        mService = service;
        mHandler = handler;
    }

2.frameworks/base/core/java/android/os/IPowerManager.aidl

[java]
inte易做图ce IPowerManager
{
...
void reboot(String reason);
...
}

inte易做图ce IPowerManager
{
...
void reboot(String reason);
...
}

3.frameworks/base/services/java/com/android/server/PowerManagerService.java

[java]
/**
* Reboot the device immediately, passing 'reason' (may be null)
* to the underlying __reboot system call. Should not return.
*/
public void reboot(String reason)
{
    mContext.enforceCallingOrSelfPermission(android.Manifest.permission.REBOOT, null);

    if (mHandler == null || !ActivityManagerNative.isSystemReady()) {
        throw new IllegalStateException("Too early to call reboot()");
    }

    final String finalReason = reason;
    Runnable runnable = new Runnable() {
        public void run() {
            synchronized (this) {
                ShutdownThread.reboot(getUiContext(), finalReason, false);
            }

        }
    };
    // ShutdownThread must run on a looper capable of displaying the UI.
    mHandler.post(runnable);

    // PowerManager.reboot() is documented not to return so just wait for the inevitable.
    synchronized (runnable) {
        while (true) {
            try {
                runnable.wait();
            } catch (InterruptedException e) {
            }
        }
    }
}

    /**
     * Reboot the device immediately, passing 'reason' (may be null)
     * to the underlying __reboot system call. Should not return.
     */
    public void reboot(String reason)
    {
        mContext.enforceCallingOrSelfPermission(android.Manifest.permission.REBOOT, null);

        if (mHandler == null || !ActivityManagerNative.isSystemReady()) {
            throw new IllegalStateException("Too early to call reboot()");
        }

        final String finalReason = reason;
        Runnable runnable = new Runnable() {
            public void run() {
                synchronized (this) {
                    ShutdownThread.reboot(getUiContext(), finalReason, false);
                }

            }
        };
        // ShutdownThread must run on a looper capable of displaying the UI.
        mHandler.post(runnable);

        // PowerManager.reboot() is documented not to return so just wait for the inevitable.
        synchronized (runnable) {
   &

补充：移动开发 , Android ,