Android_监听自身应用被卸载

1.通过jni实现函数

//LOG宏定义

#define LOG_INFO(tag, msg) __android_log_write(ANDROID_LOG_INFO, tag, msg)

#define LOG_DEBUG(tag, msg) __android_log_write(ANDROID_LOG_DEBUG, tag, msg)

#define LOG_WARN(tag, msg) __android_log_write(ANDROID_LOG_WARN, tag, msg)

#define LOG_ERROR(tag, msg) __android_log_write(ANDROID_LOG_ERROR, tag, msg)

 

/* 内全局变量begin */

staticchar c_TAG[] = "onEvent";

staticjboolean b_IS_COPY = JNI_TRUE;

 

jstring Java_com_example_uninstallself_Observer_register(JNIEnv* env,

        jobject thiz, jstring path, jstring url, jint version) {

    jstring tag = (*env)->NewStringUTF(env, c_TAG);

 

    //初始化log

    LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY),

            (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "init OK"),

                    &b_IS_COPY));

 

    //fork子进程，以执行轮询任务

    pid_t pid = fork();

    if(pid < 0) {

        //出错log

        LOG_ERROR((*env)->GetStringUTFChars(env, tag, &b_IS_COPY),

                (*env)->GetStringUTFChars(env,

                        (*env)->NewStringUTF(env,"fork failed !!!"),

                        &b_IS_COPY));

    }elseif (pid == 0) {

        //子进程注册目录监听器

        intfileDescriptor = inotify_init();

        if(fileDescriptor < 0) {

            LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY),

                    (*env)->GetStringUTFChars(env,

                            (*env)->NewStringUTF(env,

                                    "inotify_init failed !!!"), &b_IS_COPY));

 

            exit(1);

        }

 

        intwatchDescriptor;

 

        watchDescriptor = inotify_add_watch(fileDescriptor,

                (*env)->GetStringUTFChars(env, path, NULL), IN_DELETE);

        if(watchDescriptor < 0) {

            LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY),

                    (*env)->GetStringUTFChars(env,

                            (*env)->NewStringUTF(env,

                                    "inotify_add_watch failed !!!"),

                            &b_IS_COPY));

 

            exit(1);

        }

 

        //分配缓存，以便读取event，缓存大小=一个struct inotify_event的大小，这样一次处理一个event

        void*p_buf = malloc(sizeof(struct inotify_event));

        if(p_buf == NULL) {

            LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY),

                    (*env)->GetStringUTFChars(env,

                            (*env)->NewStringUTF(env,"malloc failed !!!"),

                            &b_IS_COPY));

 

            exit(1);

        }

        //开始监听

        LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY),

                (*env)->GetStringUTFChars(env,

                        (*env)->NewStringUTF(env,"start observer"),

                        &b_IS_COPY));

        //read会阻塞进程，

        size_t readBytes = read(fileDescriptor, p_buf,

                sizeof(struct inotify_event));

 

        //走到这里说明收到目录被删除的事件，注销监听器

        free(p_buf);

        inotify_rm_watch(fileDescriptor, IN_DELETE);

 

        //目录不存在log

        LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY),

                (*env)->GetStringUTFChars(env,

                        (*env)->NewStringUTF(env,"uninstalled"), &b_IS_COPY));

 

        if(version >= 17) {

            //4.2以上的系统由于用户权限管理更严格，需要加上 --user 0

            execlp("am","am","start","--user","0","-a",

                    "android.intent.action.VIEW","-d",

                    (*env)->GetStringUTFChars(env, url, NULL), (char*) NULL);

        }else{

            execlp("am","am","start","-a","android.intent.action.VIEW",

                    "-d", (*env)->GetStringUTFChars(env, url, NULL),

                    (char*) NULL);

        }

        //扩展：可以执行其他shell命令，am(即activity manager)，可以打开某程序、服务，broadcast intent，等等

 

    }else{

        //父进程直接退出，使子进程被init进程领养，以避免子进程僵死

    }

 

    return(*env)->NewStringUTF(env, "Hello from JNI !");

}

2.定义UninstallObserver

publicclass UninstallObserver {

 

    static{

        System.loadLibrary("observer");

    }

    /***

     *

     * @param path 需要监听的文件路径，可用 getApplicationContext().getFilesDir().getPath()

     * @param url 卸载调转http

     * @param version android.os.Build.VERSION.SDK_INT

     * @return

     */

    publicstatic native String register(String path, String url, intversion);

}

3.简单使用

@Override

protectedvoid onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_main);

 

    Toast.makeText(getApplicationContext(),

            getApplicationContext().getFilesDir().getPath() + ","+ Build.VERSION.SDK_INT, 1).show();

    longa = System.currentTimeMillis();

    String str = UninstallObserver.register(getApplicationContext().getFilesDir().getPath(),"http://www.baidu.com",

            android.os.Build.VERSION.SDK_INT);

    longb = System.currentTimeMillis();

    Toast.makeText(getApplicationContext(), str+","+(b-a),1).show();

 

}