android - 从 priv-app 应用程序运行 shell 命令

Question

我正在尝试从已添加到 AOSP (7.1.1) 的系统/priv-app 运行 shell 命令

我尝试运行的命令是:ip link add dev can0 type can 以打开 can 总线。

我已经将图像构建为 -eng 和 -userdebug 版本。 该命令在 adb shell 中运行良好，并按预期成功打开 CAN 总线。

我的问题是出现以下错误:

Cannot run program "su": error=13, Permission denied

当我在系统特权 java 应用程序中尝试以下代码时:

//ArrayList<String> commands is passed into the method
try {
  if (null != commands && commands.size() > 0) {
     Process suProcess = Runtime.getRuntime().exec("su");
     DataOutputStream os = new DataOutputStream(suProcess.getOutputStream());
     for (String currCommand : commands) {
        os.writeBytes(currCommand + "\n");
        os.flush();
     }
     os.writeBytes("exit\n");
     os.flush();
     BufferedReader stderr = new BufferedReader(new InputStreamReader(suProcess.getErrorStream()));
     String line = "";
     String errString = "";
     while ((line = stderr.readLine()) != null) errString += line + "\n";
     suProcess.waitFor();
     if (suProcess.exitValue() != 0)
        throw new Exception(errString);
 } //Handle exception

Answer 1

你可以这样尝试:

Process mProcess = new ProcessBuilder()
                       .command("/system/xbin/su")
                       .redirectErrorStream(true).start();

DataOutputStream out = new DataOutputStream(mProcess.getOutputStream());