Android研究之監聽自身應用被卸載代碼實現

1.通過jni實現函數

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 //LOG宏定義 #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) /* 內全局變量begin */ static char c_TAG[] = "onEvent"; static jboolean 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子進程，以執行輪詢任務 pid_t pid = fork(); if (pid < 0) { //出錯log LOG_ERROR((*env)->GetStringUTFChars(env, tag, &b_IS_COPY), (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "fork failed !!!"), &b_IS_COPY)); } else if (pid == 0) { //子進程注冊目錄監聽器 int fileDescriptor = 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); } int watchDescriptor; 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); } //分配緩存，以便讀取event，緩存大小=一個struct inotify_event的大小，這樣一次處理一個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); } //開始監聽 LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY), (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "start observer"), &b_IS_COPY)); //read會阻塞進程， size_t readBytes = read(fileDescriptor, p_buf, sizeof(struct inotify_event)); //走到這裡說明收到目錄被刪除的事件，注銷監聽器 free(p_buf); inotify_rm_watch(fileDescriptor, IN_DELETE); //目錄不存在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以上的系統由於用戶權限管理更嚴格，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); } //擴展：可以執行其他shell命令，am(即activity manager)，可以打開某程序、服務，broadcast intent，等等 } else { //父進程直接退出，使子進程被init進程領養，以避免子進程僵死 } return (*env)->NewStringUTF(env, "Hello from JNI !"); }

2.定義UninstallObserver

1 2 3 4 5 6 7 8 9 10 11 12 13 14 public class UninstallObserver { static{ System.loadLibrary("observer"); } /*** * * @param path 需要監聽的文件路徑，可用 getApplicationContext().getFilesDir().getPath() * @param url 卸載調轉http * @param version android.os.Build.VERSION.SDK_INT * @return */ public static native String register(String path, String url, int version); }

3.簡單使用

1 2 3 4 5 6 7 8 9 10 11 12 13 14 @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); Toast.makeText(getApplicationContext(), getApplicationContext().getFilesDir().getPath() + "," + Build.VERSION.SDK_INT, 1).show(); long a = System.currentTimeMillis(); String str = UninstallObserver.register(getApplicationContext().getFilesDir().getPath(), "http://www.baidu.com", android.os.Build.VERSION.SDK_INT); long b = System.currentTimeMillis(); Toast.makeText(getApplicationContext(), str+","+(b-a), 1).show(); }

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