自己写android的关机命令

<span style="font-size: 16px;">pad</span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">中自带有重启命令（</span><span style="font-size: 16px;">reboot</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">），本以为也应该有关机命令啊，可是找来找去也没有诸如</span><span style="font-size: 16px;">shutdown</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">、</span><span style="font-size: 16px;">poweroff</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">等命令。然后想到</span><span style="font-size: 16px;">busybox</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">中有一个</span><span style="font-size: 16px;">poweroff</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">命令，故又去编译了一个</span><span style="font-size: 16px;">busybox</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">推进去，执行了</span><span style="font-size: 16px;">busybox poweroff</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">之后看了下返回码是</span><span style="font-size: 16px;">0</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">（即</span><span style="font-size: 16px;">echo $?</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">），然后，然后什么也没发生……</span></span>

<span style="background-image: none; background-attachment: scroll; background-position: 0% 0%;"><span style="font-size: 16px;">网上流行的方法是在</span><span style="font-size: 16px;">Java</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%;"><span style="font-size: 16px;">端发送要求关机的</span><span style="font-size: 16px;">Intent</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%;"><span style="font-size: 16px;">，如下：</span></span>

<span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;"></span></span><pre name="code" class="java">Intent intent = new Intent(Intent.ACTION_REQUEST_SHUTDOWN);intent.putExtra(Intent.EXTRA_KEY_CONFIRM, false);intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);mContext.startActivity(intent);

<span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">需要加上相关的权限：</span></span><span style="font-size: 16px;">android:sharedUserId="android.uid.system"</span><span style="font-size: 16px;"><uses-permission android:name="android.permission.SHUTDOWN"/></span><span style="font-size: 16px;"></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">但要从</span><span style="font-size: 16px;">apk</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">中实现关机的话，那还不如手动关呢，</span></span><span style="font-size: 16px;"><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"></span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">所以自己动手了，写个诸如</span><span style="font-size: 16px;">shutdown</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">的小命令，实现也很简单，找到系统怎么处理关机的，然后我们把那段代码拿出来就行了。</span></span><span style="font-size: 16px;"></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">系统中处理关机部分的代码路径：</span><span style="font-size: 16px;">frameworks/base/core/jni/android_os_Power.cpp</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">，里面有个</span><span style="font-size: 16px;">android_os_Power_shutdown</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">方法，具体如下：</span></span><pre name="code" class="java">static void android_os_Power_shutdown(JNIEnv *env, jobject clazz){    sync();#ifdef HAVE_ANDROID_OS    reboot(RB_POWER_OFF);#endif}

<span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">看到有个</span><span style="font-size: 16px;">reboot</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">函数，然后再追踪这个</span><span style="font-size: 16px;">reboot(RB_POWER_OFF)</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">函数，看到其最终会调用</span><span style="font-size: 16px;">__reboot</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">这个函数（汇编实现的），我们只要给它传递“合适”的参数就行了。</span></span><span style="font-size: 16px;">        </span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">代码实现：</span></span><span style="font-size: 16px;">1</span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">、在</span><span style="font-size: 16px;">Android</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">源码目录中的</span><span style="font-size: 16px;">packages/apps/</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">下创建一个目录，例如：</span><span style="font-size: 16px;">Hello</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">。</span></span><span style="font-size: 16px;">2</span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">、编写</span><span style="font-size: 16px;">Android.mk</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">文件：</span></span><span style="font-size: 16px;">LOCAL_PATH:= $(call my-dir)</span><span style="font-size: 16px;">include $(CLEAR_VARS)</span><span style="font-size: 16px;"><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"></span></span><span style="font-size: 16px;">LOCAL_SRC_FILES:= shutdown.c</span><span style="font-size: 16px;"><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"></span></span><span style="font-size: 16px;">LOCAL_MODULE:= shutdown </span><span style="font-size: 16px;">LOCAL_PRELINK_MODULE:= false</span><span style="font-size: 16px;">LOCAL_SHARED_LIBRARIES:= libutils</span><span style="font-size: 16px;">include $(BUILD_EXECUTABLE)</span><span style="font-size: 16px;">3</span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">、编写</span><span style="font-size: 16px;">shutdown.c</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">源文件，如下：</span></span>

#include <stdio.h>#include <stdlib.h>#include <utils/Log.h>#include <sys/reboot.h>#ifndef LOG_TAG#define LOG_TAG "dxyh"#endifint main(int argc, char **argv){int retval;if ((retval = __reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2,RB_POWER_OFF, NULL)) < 0) {LOGE("Try to shutdown the machine failed!");exit(EXIT_FAILURE);}return 0;}

<span style="font-size: 16px;">4</span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">、</span><span style="font-size: 16px;">mm</span></span><span style="font-size: 16px;">5</span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">、将生成的</span><span style="font-size: 16px;">shutdown</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">可执行程序推入到</span><span style="font-size: 16px;">pad</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">中的</span><span style="font-size: 16px;">/system/bin</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">下即可。</span></span><span style="font-size: 16px;">6</span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">、然后就可以和其他命令一样运行了，例如</span><span style="font-size: 16px;">adb shell shutdown</span></span><span style="background-image: none; background-attachment: scroll; background-color: transparent; background-position: 0% 0%; background-repeat: repeat repeat;"><span style="font-size: 16px;">。</span></span>