src/vogar/commands/Command.java - platform/external/vogar - Git at Google

 /*
  * Copyright (C) 2009 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 vogar.commands;

 import java.io.BufferedReader;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.PrintStream;
 import java.lang.reflect.Field;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
 import vogar.Log;
 import vogar.util.Strings;

 /**
  * An out of process executable.
  */
 public final class Command {
     private static final ScheduledExecutorService timer
             = Executors.newSingleThreadScheduledExecutor();

     private final Log log;
     private final List<String> args;
     private final Map<String, String> env;
     private final File workingDirectory;
     private final boolean permitNonZeroExitStatus;
     private final PrintStream tee;
     private volatile Process process;
     private volatile boolean destroyed;
     private volatile long timeoutNanoTime;

     public Command(Log log, String... args) {
         this(log, Arrays.asList(args));
     }

     public Command(Log log, List<String> args) {
         this.log = log;
         this.args = new ArrayList<String>(args);
         this.env = Collections.emptyMap();
         this.workingDirectory = null;
         this.permitNonZeroExitStatus = false;
         this.tee = null;
     }

     private Command(Builder builder) {
         this.log = builder.log;
         this.args = new ArrayList<String>(builder.args);
         this.env = builder.env;
         this.workingDirectory = builder.workingDirectory;
         this.permitNonZeroExitStatus = builder.permitNonZeroExitStatus;
         this.tee = builder.tee;
         if (builder.maxLength != -1) {
             String string = toString();
             if (string.length() > builder.maxLength) {
                 throw new IllegalStateException("Maximum command length " + builder.maxLength
                                                 + " exceeded by: " + string);
             }
         }
     }

     public void start() throws IOException {
         if (isStarted()) {
             throw new IllegalStateException("Already started!");
         }

         // Translate ["sh", "-c", "ls", "/tmp"] into ["sh", "-c", "ls /tmp"].
         // This is needed for host execution.
         ArrayList<String> actual = new ArrayList<String>();
         int i = 0;
         while (i < args.size()) {
             String arg = args.get(i++);
             actual.add(arg);
             if (arg.equals("-c")) break;
         }
         if (i < args.size()) {
             String cmd = "";
             for (; i < args.size(); ++i) {
                 cmd += args.get(i) + " ";
             }
             actual.add(cmd);
         }

         log.verbose("executing " + actual);

         ProcessBuilder processBuilder = new ProcessBuilder()
                 .command(actual)
                 .redirectErrorStream(true);
         if (workingDirectory != null) {
             processBuilder.directory(workingDirectory);
         }

         processBuilder.environment().putAll(env);

         process = processBuilder.start();
     }

     public boolean isStarted() {
         return process != null;
     }

     public InputStream getInputStream() {
         if (!isStarted()) {
             throw new IllegalStateException("Not started!");
         }

         return process.getInputStream();
     }

     public List<String> gatherOutput()
             throws IOException, InterruptedException {
         if (!isStarted()) {
             throw new IllegalStateException("Not started!");
         }

         BufferedReader in = new BufferedReader(
                 new InputStreamReader(getInputStream(), "UTF-8"));
         List<String> outputLines = new ArrayList<String>();
         String outputLine;
         while ((outputLine = in.readLine()) != null) {
             if (tee != null) {
                 tee.println(outputLine);
             }
             outputLines.add(outputLine);
         }

         int exitValue = process.waitFor();
         destroyed = true;
         if (exitValue != 0 && !permitNonZeroExitStatus) {
             StringBuilder message = new StringBuilder();
             for (String line : outputLines) {
                 message.append("\n").append(line);
             }
             throw new CommandFailedException(args, outputLines);
         }

         return outputLines;
     }

     public List<String> execute() {
         try {
             start();
             return gatherOutput();
         } catch (IOException e) {
             throw new RuntimeException("Failed to execute process: " + args, e);
         } catch (InterruptedException e) {
             throw new RuntimeException("Interrupted while executing process: " + args, e);
         }
     }

     /**
      * Executes a command with a specified timeout. If the process does not
      * complete normally before the timeout has elapsed, it will be destroyed.
      *
      * @param timeoutSeconds how long to wait, or 0 to wait indefinitely
      * @return the command's output, or null if the command timed out
      */
     public List<String> executeWithTimeout(int timeoutSeconds) throws TimeoutException {
         if (timeoutSeconds == 0) {
             return execute();
         }

         scheduleTimeout(timeoutSeconds);
         return execute();
     }

     /**
      * Destroys the underlying process and closes its associated streams.
      */
     public void destroy() {
         Process process = this.process;
         if (process == null) {
             throw new IllegalStateException();
         }
         if (destroyed) {
             return;
         }

         destroyed = true;
         process.destroy();
         try {
             process.waitFor();
             int exitValue = process.exitValue();
             log.verbose("received exit value " + exitValue + " from destroyed command " + this);
         } catch (IllegalThreadStateException destroyUnsuccessful) {
             log.warn("couldn't destroy " + this);
         } catch (InterruptedException e) {
             log.warn("couldn't destroy " + this);
         }
     }

     @Override public String toString() {
         String envString = !env.isEmpty() ? (Strings.join(env.entrySet(), " ") + " ") : "";
         return envString + Strings.join(args, " ");
     }

     /**
      * Sets the time at which this process will be killed. If a timeout has
      * already been scheduled, it will be rescheduled.
      */
     public void scheduleTimeout(int timeoutSeconds) {
         timeoutNanoTime = System.nanoTime() + TimeUnit.SECONDS.toNanos(timeoutSeconds);

         new TimeoutTask() {
             @Override protected void onTimeout(Process process) {
                 // send a quit signal immediately
                 log.verbose("sending quit signal to command " + Command.this);
                 sendQuitSignal(process);

                 // hard kill in 2 seconds
                 timeoutNanoTime = System.nanoTime() + TimeUnit.SECONDS.toNanos(2);
                 new TimeoutTask() {
                     @Override protected void onTimeout(Process process) {
                         log.verbose("killing timed out command " + Command.this);
                         destroy();
                     }
                 }.schedule();
             }
         }.schedule();
     }

     private void sendQuitSignal(Process process) {
         // TODO: 'adb shell kill' to kill on processes running on Androids
         new Command(log, "kill", "-3", Integer.toString(getPid(process))).execute();
     }

     /**
      * Return the PID of this command's process.
      */
     private int getPid(Process process) {
         try {
             // See org.openqa.selenium.ProcessUtils.getProcessId()
             Field field = process.getClass().getDeclaredField("pid");
             field.setAccessible(true);
             return (Integer) field.get(process);
         } catch (Exception e) {
             throw new RuntimeException(e);
         }
     }

     public boolean timedOut() {
         return System.nanoTime() >= timeoutNanoTime;
     }

     public static class Builder {
         private final Log log;
         private final List<String> args = new ArrayList<String>();
         private final Map<String, String> env = new LinkedHashMap<String, String>();
         private File workingDirectory;
         private boolean permitNonZeroExitStatus = false;
         private PrintStream tee = null;
         private int maxLength = -1;

         public Builder(Log log) {
             this.log = log;
         }

         public Builder(Builder other) {
             this.log = other.log;
             this.args.addAll(other.args);
             this.env.putAll(other.env);
             this.workingDirectory = other.workingDirectory;
             this.permitNonZeroExitStatus = other.permitNonZeroExitStatus;
             this.tee = other.tee;
             this.maxLength = other.maxLength;
         }

         public Builder args(Object... args) {
             return args(Arrays.asList(args));
         }

         public Builder args(Collection<?> args) {
             for (Object object : args) {
                 this.args.add(object.toString());
             }
             return this;
         }

         public Builder env(String key, String value) {
             env.put(key, value);
             return this;
         }

         /**
          * Sets the working directory from which the command will be executed.
          * This must be a <strong>local</strong> directory; Commands run on
          * remote devices (ie. via {@code adb shell}) require a local working
          * directory.
          */
         public Builder workingDirectory(File workingDirectory) {
             this.workingDirectory = workingDirectory;
             return this;
         }

         /**
          * Prevents execute() from throwing if the invoked process returns a
          * nonzero exit code.
          */
         public Builder permitNonZeroExitStatus() {
             this.permitNonZeroExitStatus = true;
             return this;
         }

         public Builder tee(PrintStream printStream) {
             tee = printStream;
             return this;
         }

         public Builder maxLength(int maxLength) {
             this.maxLength = maxLength;
             return this;
         }

         public Command build() {
             return new Command(this);
         }

         public List<String> execute() {
             return build().execute();
         }
     }

     /**
      * Runs some code when the command times out.
      */
     private abstract class TimeoutTask implements Runnable {
         public final void schedule() {
             timer.schedule(this, System.nanoTime() - timeoutNanoTime, TimeUnit.NANOSECONDS);
         }

         protected abstract void onTimeout(Process process);

         @Override public final void run() {
             // don't destroy commands that have already been destroyed
             Process process = Command.this.process;
             if (destroyed) {
                 return;
             }

             if (timedOut()) {
                 onTimeout(process);
             } else {
                 // if the kill time has been pushed back, reschedule
                 timer.schedule(this, System.nanoTime() - timeoutNanoTime, TimeUnit.NANOSECONDS);
             }
         }
     }
 }
	/*
	* Copyright (C) 2009 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 vogar.commands;

	import java.io.BufferedReader;
	import java.io.File;
	import java.io.IOException;
	import java.io.InputStream;
	import java.io.InputStreamReader;
	import java.io.PrintStream;
	import java.lang.reflect.Field;
	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.Collection;
	import java.util.Collections;
	import java.util.LinkedHashMap;
	import java.util.List;
	import java.util.Map;
	import java.util.concurrent.Executors;
	import java.util.concurrent.ScheduledExecutorService;
	import java.util.concurrent.TimeUnit;
	import java.util.concurrent.TimeoutException;
	import vogar.Log;
	import vogar.util.Strings;

	/**
	* An out of process executable.
	*/
	public final class Command {
	private static final ScheduledExecutorService timer
	= Executors.newSingleThreadScheduledExecutor();

	private final Log log;
	private final List<String> args;
	private final Map<String, String> env;
	private final File workingDirectory;
	private final boolean permitNonZeroExitStatus;
	private final PrintStream tee;
	private volatile Process process;
	private volatile boolean destroyed;
	private volatile long timeoutNanoTime;

	public Command(Log log, String... args) {
	this(log, Arrays.asList(args));
	}

	public Command(Log log, List<String> args) {
	this.log = log;
	this.args = new ArrayList<String>(args);
	this.env = Collections.emptyMap();
	this.workingDirectory = null;
	this.permitNonZeroExitStatus = false;
	this.tee = null;
	}

	private Command(Builder builder) {
	this.log = builder.log;
	this.args = new ArrayList<String>(builder.args);
	this.env = builder.env;
	this.workingDirectory = builder.workingDirectory;
	this.permitNonZeroExitStatus = builder.permitNonZeroExitStatus;
	this.tee = builder.tee;
	if (builder.maxLength != -1) {
	String string = toString();
	if (string.length() > builder.maxLength) {
	throw new IllegalStateException("Maximum command length " + builder.maxLength
	+ " exceeded by: " + string);
	}
	}
	}

	public void start() throws IOException {
	if (isStarted()) {
	throw new IllegalStateException("Already started!");
	}

	// Translate ["sh", "-c", "ls", "/tmp"] into ["sh", "-c", "ls /tmp"].
	// This is needed for host execution.
	ArrayList<String> actual = new ArrayList<String>();
	int i = 0;
	while (i < args.size()) {
	String arg = args.get(i++);
	actual.add(arg);
	if (arg.equals("-c")) break;
	}
	if (i < args.size()) {
	String cmd = "";
	for (; i < args.size(); ++i) {
	cmd += args.get(i) + " ";
	}
	actual.add(cmd);
	}

	log.verbose("executing " + actual);

	ProcessBuilder processBuilder = new ProcessBuilder()
	.command(actual)
	.redirectErrorStream(true);
	if (workingDirectory != null) {
	processBuilder.directory(workingDirectory);
	}

	processBuilder.environment().putAll(env);

	process = processBuilder.start();
	}

	public boolean isStarted() {
	return process != null;
	}

	public InputStream getInputStream() {
	if (!isStarted()) {
	throw new IllegalStateException("Not started!");
	}

	return process.getInputStream();
	}

	public List<String> gatherOutput()
	throws IOException, InterruptedException {
	if (!isStarted()) {
	throw new IllegalStateException("Not started!");
	}

	BufferedReader in = new BufferedReader(
	new InputStreamReader(getInputStream(), "UTF-8"));
	List<String> outputLines = new ArrayList<String>();
	String outputLine;
	while ((outputLine = in.readLine()) != null) {
	if (tee != null) {
	tee.println(outputLine);
	}
	outputLines.add(outputLine);
	}

	int exitValue = process.waitFor();
	destroyed = true;
	if (exitValue != 0 && !permitNonZeroExitStatus) {
	StringBuilder message = new StringBuilder();
	for (String line : outputLines) {
	message.append("\n").append(line);
	}
	throw new CommandFailedException(args, outputLines);
	}

	return outputLines;
	}

	public List<String> execute() {
	try {
	start();
	return gatherOutput();
	} catch (IOException e) {
	throw new RuntimeException("Failed to execute process: " + args, e);
	} catch (InterruptedException e) {
	throw new RuntimeException("Interrupted while executing process: " + args, e);
	}
	}

	/**
	* Executes a command with a specified timeout. If the process does not
	* complete normally before the timeout has elapsed, it will be destroyed.
	*
	* @param timeoutSeconds how long to wait, or 0 to wait indefinitely
	* @return the command's output, or null if the command timed out
	*/
	public List<String> executeWithTimeout(int timeoutSeconds) throws TimeoutException {
	if (timeoutSeconds == 0) {
	return execute();
	}

	scheduleTimeout(timeoutSeconds);
	return execute();
	}

	/**
	* Destroys the underlying process and closes its associated streams.
	*/
	public void destroy() {
	Process process = this.process;
	if (process == null) {
	throw new IllegalStateException();
	}
	if (destroyed) {
	return;
	}

	destroyed = true;
	process.destroy();
	try {
	process.waitFor();
	int exitValue = process.exitValue();
	log.verbose("received exit value " + exitValue + " from destroyed command " + this);
	} catch (IllegalThreadStateException destroyUnsuccessful) {
	log.warn("couldn't destroy " + this);
	} catch (InterruptedException e) {
	log.warn("couldn't destroy " + this);
	}
	}

	@Override public String toString() {
	String envString = !env.isEmpty() ? (Strings.join(env.entrySet(), " ") + " ") : "";
	return envString + Strings.join(args, " ");
	}

	/**
	* Sets the time at which this process will be killed. If a timeout has
	* already been scheduled, it will be rescheduled.
	*/
	public void scheduleTimeout(int timeoutSeconds) {
	timeoutNanoTime = System.nanoTime() + TimeUnit.SECONDS.toNanos(timeoutSeconds);

	new TimeoutTask() {
	@Override protected void onTimeout(Process process) {
	// send a quit signal immediately
	log.verbose("sending quit signal to command " + Command.this);
	sendQuitSignal(process);

	// hard kill in 2 seconds
	timeoutNanoTime = System.nanoTime() + TimeUnit.SECONDS.toNanos(2);
	new TimeoutTask() {
	@Override protected void onTimeout(Process process) {
	log.verbose("killing timed out command " + Command.this);
	destroy();
	}
	}.schedule();
	}
	}.schedule();
	}

	private void sendQuitSignal(Process process) {
	// TODO: 'adb shell kill' to kill on processes running on Androids
	new Command(log, "kill", "-3", Integer.toString(getPid(process))).execute();
	}

	/**
	* Return the PID of this command's process.
	*/
	private int getPid(Process process) {
	try {
	// See org.openqa.selenium.ProcessUtils.getProcessId()
	Field field = process.getClass().getDeclaredField("pid");
	field.setAccessible(true);
	return (Integer) field.get(process);
	} catch (Exception e) {
	throw new RuntimeException(e);
	}
	}

	public boolean timedOut() {
	return System.nanoTime() >= timeoutNanoTime;
	}

	public static class Builder {
	private final Log log;
	private final List<String> args = new ArrayList<String>();
	private final Map<String, String> env = new LinkedHashMap<String, String>();
	private File workingDirectory;
	private boolean permitNonZeroExitStatus = false;
	private PrintStream tee = null;
	private int maxLength = -1;

	public Builder(Log log) {
	this.log = log;
	}

	public Builder(Builder other) {
	this.log = other.log;
	this.args.addAll(other.args);
	this.env.putAll(other.env);
	this.workingDirectory = other.workingDirectory;
	this.permitNonZeroExitStatus = other.permitNonZeroExitStatus;
	this.tee = other.tee;
	this.maxLength = other.maxLength;
	}

	public Builder args(Object... args) {
	return args(Arrays.asList(args));
	}

	public Builder args(Collection<?> args) {
	for (Object object : args) {
	this.args.add(object.toString());
	}
	return this;
	}

	public Builder env(String key, String value) {
	env.put(key, value);
	return this;
	}

	/**
	* Sets the working directory from which the command will be executed.
	* This must be a <strong>local</strong> directory; Commands run on
	* remote devices (ie. via {@code adb shell}) require a local working
	* directory.
	*/
	public Builder workingDirectory(File workingDirectory) {
	this.workingDirectory = workingDirectory;
	return this;
	}

	/**
	* Prevents execute() from throwing if the invoked process returns a
	* nonzero exit code.
	*/
	public Builder permitNonZeroExitStatus() {
	this.permitNonZeroExitStatus = true;
	return this;
	}

	public Builder tee(PrintStream printStream) {
	tee = printStream;
	return this;
	}

	public Builder maxLength(int maxLength) {
	this.maxLength = maxLength;
	return this;
	}

	public Command build() {
	return new Command(this);
	}

	public List<String> execute() {
	return build().execute();
	}
	}

	/**
	* Runs some code when the command times out.
	*/
	private abstract class TimeoutTask implements Runnable {
	public final void schedule() {
	timer.schedule(this, System.nanoTime() - timeoutNanoTime, TimeUnit.NANOSECONDS);
	}

	protected abstract void onTimeout(Process process);

	@Override public final void run() {
	// don't destroy commands that have already been destroyed
	Process process = Command.this.process;
	if (destroyed) {
	return;
	}

	if (timedOut()) {
	onTimeout(process);
	} else {
	// if the kill time has been pushed back, reschedule
	timer.schedule(this, System.nanoTime() - timeoutNanoTime, TimeUnit.NANOSECONDS);
	}
	}
	}
	}