Move BasicShellCommandHandler
The class is currently used by the framework and mainline modules,
including telephony, wifi mainline module and the incoming
ConnectivityService module. For these kind of class that are shared
between the framework and modules should be placed in modules-utils.
Thus, move this class to this folder which was created for putting
such utils class. Also, classes inside framework(e.g. ShellCommand)
extend BasicShellCommandHandler, and it uses these two parent's
members. But they are now in different packages after
BasicShellCommandHandler is moved to modules-utils. Thus, also
update TAG and DEBUG to protected.
Bug: 170598012
Test: m
Change-Id: Ib750f477490692f6664934986228959e965c990a
diff --git a/os/Android.bp b/os/Android.bp
new file mode 100644
index 0000000..ca67826
--- /dev/null
+++ b/os/Android.bp
@@ -0,0 +1,27 @@
+//
+// Copyright (C) 2020 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+java_library {
+ name: "modules-utils-os",
+
+ srcs: [
+ "src/**/*.java",
+ ],
+ sdk_version: "module_current",
+ apex_available: [
+ "//apex_available:anyapex",
+ "//apex_available:platform",
+ ],
+}
\ No newline at end of file
diff --git a/os/src/com/android/modules/utils/BasicShellCommandHandler.java b/os/src/com/android/modules/utils/BasicShellCommandHandler.java
new file mode 100644
index 0000000..2efe391
--- /dev/null
+++ b/os/src/com/android/modules/utils/BasicShellCommandHandler.java
@@ -0,0 +1,343 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.modules.utils;
+
+import android.util.Log;
+import android.os.Binder;
+
+import java.io.BufferedInputStream;
+import java.io.FileDescriptor;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.PrintWriter;
+
+/**
+ * Helper for implementing {@link Binder#onShellCommand Binder.onShellCommand}. This is meant to
+ * be copied into mainline modules, so this class must not use any hidden APIs.
+ *
+ * @hide
+ */
+public abstract class BasicShellCommandHandler {
+ protected static final String TAG = "ShellCommand";
+ protected static final boolean DEBUG = false;
+
+ private Binder mTarget;
+ private FileDescriptor mIn;
+ private FileDescriptor mOut;
+ private FileDescriptor mErr;
+ private String[] mArgs;
+
+ private String mCmd;
+ private int mArgPos;
+ private String mCurArgData;
+
+ private FileInputStream mFileIn;
+ private FileOutputStream mFileOut;
+ private FileOutputStream mFileErr;
+
+ private PrintWriter mOutPrintWriter;
+ private PrintWriter mErrPrintWriter;
+ private InputStream mInputStream;
+
+ public void init(Binder target, FileDescriptor in, FileDescriptor out, FileDescriptor err,
+ String[] args, int firstArgPos) {
+ mTarget = target;
+ mIn = in;
+ mOut = out;
+ mErr = err;
+ mArgs = args;
+ mCmd = null;
+ mArgPos = firstArgPos;
+ mCurArgData = null;
+ mFileIn = null;
+ mFileOut = null;
+ mFileErr = null;
+ mOutPrintWriter = null;
+ mErrPrintWriter = null;
+ mInputStream = null;
+ }
+
+ public int exec(Binder target, FileDescriptor in, FileDescriptor out, FileDescriptor err,
+ String[] args) {
+ String cmd;
+ int start;
+ if (args != null && args.length > 0) {
+ cmd = args[0];
+ start = 1;
+ } else {
+ cmd = null;
+ start = 0;
+ }
+ init(target, in, out, err, args, start);
+ mCmd = cmd;
+
+ if (DEBUG) {
+ RuntimeException here = new RuntimeException("here");
+ here.fillInStackTrace();
+ Log.d(TAG, "Starting command " + mCmd + " on " + mTarget, here);
+ Log.d(TAG, "Calling uid=" + Binder.getCallingUid()
+ + " pid=" + Binder.getCallingPid());
+ }
+ int res = -1;
+ try {
+ res = onCommand(mCmd);
+ if (DEBUG) Log.d(TAG, "Executed command " + mCmd + " on " + mTarget);
+ } catch (Throwable e) {
+ // Unlike usual calls, in this case if an exception gets thrown
+ // back to us we want to print it back in to the dump data, since
+ // that is where the caller expects all interesting information to
+ // go.
+ PrintWriter eout = getErrPrintWriter();
+ eout.println();
+ eout.println("Exception occurred while executing '" + mCmd + "':");
+ e.printStackTrace(eout);
+ } finally {
+ if (DEBUG) Log.d(TAG, "Flushing output streams on " + mTarget);
+ if (mOutPrintWriter != null) {
+ mOutPrintWriter.flush();
+ }
+ if (mErrPrintWriter != null) {
+ mErrPrintWriter.flush();
+ }
+ if (DEBUG) Log.d(TAG, "Sending command result on " + mTarget);
+ }
+ if (DEBUG) Log.d(TAG, "Finished command " + mCmd + " on " + mTarget);
+ return res;
+ }
+
+ /**
+ * Return the raw FileDescriptor for the output stream.
+ */
+ public FileDescriptor getOutFileDescriptor() {
+ return mOut;
+ }
+
+ /**
+ * Return direct raw access (not buffered) to the command's output data stream.
+ */
+ public OutputStream getRawOutputStream() {
+ if (mFileOut == null) {
+ mFileOut = new FileOutputStream(mOut);
+ }
+ return mFileOut;
+ }
+
+ /**
+ * Return a PrintWriter for formatting output to {@link #getRawOutputStream()}.
+ */
+ public PrintWriter getOutPrintWriter() {
+ if (mOutPrintWriter == null) {
+ mOutPrintWriter = new PrintWriter(getRawOutputStream());
+ }
+ return mOutPrintWriter;
+ }
+
+ /**
+ * Return the raw FileDescriptor for the error stream.
+ */
+ public FileDescriptor getErrFileDescriptor() {
+ return mErr;
+ }
+
+ /**
+ * Return direct raw access (not buffered) to the command's error output data stream.
+ */
+ public OutputStream getRawErrorStream() {
+ if (mFileErr == null) {
+ mFileErr = new FileOutputStream(mErr);
+ }
+ return mFileErr;
+ }
+
+ /**
+ * Return a PrintWriter for formatting output to {@link #getRawErrorStream()}.
+ */
+ public PrintWriter getErrPrintWriter() {
+ if (mErr == null) {
+ return getOutPrintWriter();
+ }
+ if (mErrPrintWriter == null) {
+ mErrPrintWriter = new PrintWriter(getRawErrorStream());
+ }
+ return mErrPrintWriter;
+ }
+
+ /**
+ * Return the raw FileDescriptor for the input stream.
+ */
+ public FileDescriptor getInFileDescriptor() {
+ return mIn;
+ }
+
+ /**
+ * Return direct raw access (not buffered) to the command's input data stream.
+ */
+ public InputStream getRawInputStream() {
+ if (mFileIn == null) {
+ mFileIn = new FileInputStream(mIn);
+ }
+ return mFileIn;
+ }
+
+ /**
+ * Return buffered access to the command's {@link #getRawInputStream()}.
+ */
+ public InputStream getBufferedInputStream() {
+ if (mInputStream == null) {
+ mInputStream = new BufferedInputStream(getRawInputStream());
+ }
+ return mInputStream;
+ }
+
+ /**
+ * Return the next option on the command line -- that is an argument that
+ * starts with '-'. If the next argument is not an option, null is returned.
+ */
+ public String getNextOption() {
+ if (mCurArgData != null) {
+ String prev = mArgs[mArgPos - 1];
+ throw new IllegalArgumentException("No argument expected after \"" + prev + "\"");
+ }
+ if (mArgPos >= mArgs.length) {
+ return null;
+ }
+ String arg = mArgs[mArgPos];
+ if (!arg.startsWith("-")) {
+ return null;
+ }
+ mArgPos++;
+ if (arg.equals("--")) {
+ return null;
+ }
+ if (arg.length() > 1 && arg.charAt(1) != '-') {
+ if (arg.length() > 2) {
+ mCurArgData = arg.substring(2);
+ return arg.substring(0, 2);
+ } else {
+ mCurArgData = null;
+ return arg;
+ }
+ }
+ mCurArgData = null;
+ return arg;
+ }
+
+ /**
+ * Return the next argument on the command line, whatever it is; if there are
+ * no arguments left, return null.
+ */
+ public String getNextArg() {
+ if (mCurArgData != null) {
+ String arg = mCurArgData;
+ mCurArgData = null;
+ return arg;
+ } else if (mArgPos < mArgs.length) {
+ return mArgs[mArgPos++];
+ } else {
+ return null;
+ }
+ }
+
+ public String peekNextArg() {
+ if (mCurArgData != null) {
+ return mCurArgData;
+ } else if (mArgPos < mArgs.length) {
+ return mArgs[mArgPos];
+ } else {
+ return null;
+ }
+ }
+
+ /**
+ * @return all the remaining arguments in the command without moving the current position.
+ */
+ public String[] peekRemainingArgs() {
+ int remaining = getRemainingArgsCount();
+ String[] args = new String[remaining];
+ for (int pos = mArgPos; pos < mArgs.length; pos++) {
+ args[pos - mArgPos] = mArgs[pos];
+ }
+ return args;
+ }
+
+ /**
+ * Returns number of arguments that haven't been processed yet.
+ */
+ public int getRemainingArgsCount() {
+ if (mArgPos >= mArgs.length) {
+ return 0;
+ }
+ return mArgs.length - mArgPos;
+ }
+
+ /**
+ * Return the next argument on the command line, whatever it is; if there are
+ * no arguments left, throws an IllegalArgumentException to report this to the user.
+ */
+ public String getNextArgRequired() {
+ String arg = getNextArg();
+ if (arg == null) {
+ String prev = mArgs[mArgPos - 1];
+ throw new IllegalArgumentException("Argument expected after \"" + prev + "\"");
+ }
+ return arg;
+ }
+
+ public int handleDefaultCommands(String cmd) {
+ if (cmd == null || "help".equals(cmd) || "-h".equals(cmd)) {
+ onHelp();
+ } else {
+ getOutPrintWriter().println("Unknown command: " + cmd);
+ }
+ return -1;
+ }
+
+ public Binder getTarget() {
+ return mTarget;
+ }
+
+ public String[] getAllArgs() {
+ return mArgs;
+ }
+
+ /**
+ * Implement parsing and execution of a command. If it isn't a command you understand,
+ * call {@link #handleDefaultCommands(String)} and return its result as a last resort.
+ * Use {@link #getNextOption()}, {@link #getNextArg()}, and {@link #getNextArgRequired()}
+ * to process additional command line arguments. Command output can be written to
+ * {@link #getOutPrintWriter()} and errors to {@link #getErrPrintWriter()}.
+ *
+ * <p class="caution">Note that no permission checking has been done before entering this
+ * function, so you need to be sure to do your own security verification for any commands you
+ * are executing. The easiest way to do this is to have the ShellCommand contain
+ * only a reference to your service's aidl interface, and do all of your command
+ * implementations on top of that -- that way you can rely entirely on your executing security
+ * code behind that interface.</p>
+ *
+ * @param cmd The first command line argument representing the name of the command to execute.
+ * @return Return the command result; generally 0 or positive indicates success and
+ * negative values indicate error.
+ */
+ public abstract int onCommand(String cmd);
+
+ /**
+ * Implement this to print help text about your command to {@link #getOutPrintWriter()}.
+ */
+ public abstract void onHelp();
+}
