1、recovery函数：

#define	UPDATE_TITLE			"--update_package="#define UPDATE_COMMAND_FILE		"/cache/recovery/command"#define UPDATE_FLAG_FILE		"/cache/recovery/last_flag"#define LAST_INSTALL_FILE		"/cache/recovery/last_install"#define LAST_LOG_FILE			"/cache/recovery/last_log"#define LAST_LOCALE_FILE		"/cache/recovery/last_locale"#define printf 	ALOGDint factory_data_reset(void){	char data[] = {"--wipe_data\n--locale=en_US\n"};	int len = 0, fd;	printf("[%s]command:%s\n", __FUNCTION__, data);		fd = open(UPDATE_COMMAND_FILE, O_RDWR|O_CREAT|O_TRUNC, S_IRUSR|S_IWUSR);	if (fd < 0)	{		printf("[%s]creat command file failed\n", __FUNCTION__);		return -3;	}	len = strlen(data);	if (write(fd, data, len) != len)	{		printf("[%s]write command file failed\n", __FUNCTION__);		close(fd);		return -4;	}	close(fd);	//delete last_install,last_log	if (remove(LAST_INSTALL_FILE) != 0)		printf("[%s]remove last_install failed\n", __FUNCTION__);	if (remove(LAST_LOG_FILE) != 0)		printf("[%s]remove last_log failed\n", __FUNCTION__);			if (remove(LAST_LOCALE_FILE) != 0)		printf("[%s]remove last_locale failed\n", __FUNCTION__);	sync();	//reboot to recovery	__reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, LINUX_REBOOT_CMD_RESTART2, (void*) "recovery");//这句须要root权限！	printf("[%s]reboot failed\n", __FUNCTION__);	return -7;}

2、OTA升级函数

int install_ota_package(char const * package_file, int use_fuse){	char *path = NULL;	int len = 0, size, fd;		len = strlen(package_file);	if (len <= 0)	{		printf("[%s]strlen(package_file)=%d\n", __FUNCTION__, len);		return -1;	}		path = (char*)malloc(len+24+3);	if (path == 0)	{		printf("[%s]malloc failed\n", __FUNCTION__);		return -2;	}		//UPDATE_COMMAND_FILE	memset(path, 0, len+24+3);	if (use_fuse)//(strncmp(package_file, "/vtfuse", 7) != 0)	{		strcpy(path, "--update_package=/vtfuse");		strcpy(&path[24], package_file);		strcpy(&path[24+len], "\n");	}	else	{		strcpy(path, "--update_package=");		strcpy(&path[17], package_file);		strcpy(&path[17+len], "\n");	}	printf("[%s]command:%s\n", __FUNCTION__, path);		fd = open(UPDATE_COMMAND_FILE, O_RDWR|O_CREAT|O_TRUNC, S_IRUSR|S_IWUSR);	if (fd < 0)	{		printf("[%s]creat command file failed\n", __FUNCTION__);		free(path);		return -3;	}	size = strlen(path);	if (write(fd, path, size) != size)	{		printf("[%s]write command file failed\n", __FUNCTION__);		free(path);		close(fd);		return -4;	}	close(fd);		//UPDATE_FLAG_FILE	memset(path, 0, len+24+3);	if (use_fuse)//(strncmp(package_file, "/vtfuse", 7) != 0)	{		strcpy(path, "updating$path=/vtfuse");		strcpy(&path[21], package_file);		strcpy(&path[21+len], "\n");	}	else	{		strcpy(path, "updating$path=");		strcpy(&path[14], package_file);		strcpy(&path[14+len], "\n");	}	printf("[%s]last_flag:%s\n", __FUNCTION__, path);		fd = open(UPDATE_FLAG_FILE, O_RDWR|O_CREAT|O_TRUNC, S_IRUSR|S_IWUSR);	if (fd < 0)	{		printf("[%s]creat last_flag file failed\n", __FUNCTION__);		free(path);		return -5;	}	size = strlen(path);	if (write(fd, path, size) != size)	{		printf("[%s]write last_flag file failed\n", __FUNCTION__);		free(path);		close(fd);		return -6;	}	close(fd);		//delete last_install,last_log	if (remove(LAST_INSTALL_FILE) != 0)		printf("[%s]remove last_install failed\n", __FUNCTION__);	if (remove(LAST_LOG_FILE) != 0)		printf("[%s]remove last_log failed\n", __FUNCTION__);	sync();	free(path);		//reboot to recovery	__reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, LINUX_REBOOT_CMD_RESTART2, (void*) "recovery");//相同须要root权限	printf("[%s]reboot failed\n", __FUNCTION__);	return -7;}

3、事实上上面两个函数假设编译成exe在root下执行确实能够实现recovery和OTA升级。怎样在jni或者apk中掉用和实现了？

3.1 apk申请system权限，须要签名或者在源代码中编译！

3.2 apk是无法直接获取到root权限的，最多system权限，因此我们能够採service！

參考：http://blog.chinaunix.net/uid-12348673-id-3030823.html

3.3 将上面的函数写两个应用。编译后放在/system/bin/下，这样我们就可以在jni中或apk中去开启service：

init.rc中：

 servicerecovery /system/bin/recovery

 disabled

apk： SystemProperties.set("ctl.start", "recovery");

jni： property_set("ctl.start", "recovery");

3.4这样就能够实现recovery，OTA了！