/*
* Copyright 2010 the original author or authors.
*
* 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 org.gradle.process.internal;
import com.google.common.base.Joiner;
import net.rubygrapefruit.platform.ProcessLauncher;
import org.gradle.api.logging.Logger;
import org.gradle.api.logging.Logging;
import org.gradle.internal.concurrent.DefaultExecutorFactory;
import org.gradle.internal.concurrent.StoppableExecutor;
import org.gradle.internal.nativeintegration.services.NativeServices;
import org.gradle.listener.ListenerBroadcast;
import org.gradle.process.ExecResult;
import org.gradle.process.internal.shutdown.ShutdownHookActionRegister;
import org.gradle.process.internal.streams.StreamsHandler;
import java.io.File;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
/**
* Default implementation for the ExecHandle interface.
*
* <h3>State flows</h3>
*
* <ul>
* <li>INIT -> STARTED -> [SUCCEEDED|FAILED|ABORTED|DETACHED]</li>
* <li>INIT -> FAILED</li>
* <li>INIT -> STARTED -> DETACHED -> ABORTED</li>
* </ul>
*
* State is controlled on all control methods:
* <ul>
* <li>{@link #start()} allowed when state is INIT</li>
* <li>{@link #abort()} allowed when state is STARTED or DETACHED</li>
* </ul>
*/
public class DefaultExecHandle implements ExecHandle, ProcessSettings {
private static final Logger LOGGER = Logging.getLogger(DefaultExecHandle.class);
private final String displayName;
/**
* The working directory of the process.
*/
private final File directory;
/**
* The executable to run.
*/
private final String command;
/**
* Arguments to pass to the executable.
*/
private final List<String> arguments;
/**
* The variables to set in the environment the executable is run in.
*/
private final Map<String, String> environment;
private final StreamsHandler streamsHandler;
private final boolean redirectErrorStream;
private final ProcessLauncher processLauncher;
private int timeoutMillis;
private boolean daemon;
/**
* Lock to guard all mutable state
*/
private final Lock lock;
private final Condition condition;
private final StoppableExecutor executor;
/**
* State of this ExecHandle.
*/
private ExecHandleState state;
/**
* When not null, the runnable that is waiting
*/
private ExecHandleRunner execHandleRunner;
private ExecResultImpl execResult;
private final ListenerBroadcast<ExecHandleListener> broadcast;
private final ExecHandleShutdownHookAction shutdownHookAction;
DefaultExecHandle(String displayName, File directory, String command, List<String> arguments,
Map<String, String> environment, StreamsHandler streamsHandler,
List<ExecHandleListener> listeners, boolean redirectErrorStream, int timeoutMillis, boolean daemon) {
this.displayName = displayName;
this.directory = directory;
this.command = command;
this.arguments = arguments;
this.environment = environment;
this.streamsHandler = streamsHandler;
this.redirectErrorStream = redirectErrorStream;
this.timeoutMillis = timeoutMillis;
this.daemon = daemon;
this.lock = new ReentrantLock();
this.condition = lock.newCondition();
this.state = ExecHandleState.INIT;
executor = new DefaultExecutorFactory().create(String.format("Run %s", displayName));
processLauncher = NativeServices.getInstance().get(ProcessLauncher.class);
shutdownHookAction = new ExecHandleShutdownHookAction(this);
broadcast = new ListenerBroadcast<ExecHandleListener>(ExecHandleListener.class);
broadcast.addAll(listeners);
}
public File getDirectory() {
return directory;
}
public String getCommand() {
return command;
}
public boolean isDaemon() {
return daemon;
}
@Override
public String toString() {
return displayName;
}
public List<String> getArguments() {
return Collections.unmodifiableList(arguments);
}
public Map<String, String> getEnvironment() {
return Collections.unmodifiableMap(environment);
}
public ExecHandleState getState() {
lock.lock();
try {
return state;
} finally {
lock.unlock();
}
}
private void setState(ExecHandleState state) {
lock.lock();
try {
LOGGER.debug("Changing state to: {}", state);
this.state = state;
this.condition.signalAll();
} finally {
lock.unlock();
}
}
private boolean stateIn(ExecHandleState... states) {
lock.lock();
try {
return Arrays.asList(states).contains(this.state);
} finally {
lock.unlock();
}
}
private void setEndStateInfo(ExecHandleState newState, int exitValue, Throwable failureCause) {
ShutdownHookActionRegister.removeAction(shutdownHookAction);
ExecResultImpl result;
ExecHandleState currentState;
lock.lock();
try {
currentState = this.state;
ExecException wrappedException = null;
if (failureCause != null) {
if (currentState == ExecHandleState.STARTING) {
wrappedException = new ExecException(String.format("A problem occurred starting process '%s'",
displayName), failureCause);
} else {
wrappedException = new ExecException(String.format(
"A problem occurred waiting for process '%s' to complete.", displayName), failureCause);
}
}
setState(newState);
execResult = new ExecResultImpl(exitValue, wrappedException, displayName);
result = execResult;
} finally {
lock.unlock();
}
LOGGER.debug("Process '{}' finished with exit value {} (state: {})", displayName, exitValue, newState);
if (currentState != ExecHandleState.DETACHED && newState != ExecHandleState.DETACHED) {
broadcast.getSource().executionFinished(this, result);
}
executor.requestStop();
}
public ExecHandle start() {
LOGGER.info("Starting process '{}'. Working directory: {} Command: {}",
displayName, directory, command + ' ' + Joiner.on(' ').useForNull("null").join(arguments));
if (LOGGER.isDebugEnabled()) {
LOGGER.debug("Environment for process '{}': {}", displayName, environment);
}
lock.lock();
try {
if (!stateIn(ExecHandleState.INIT)) {
throw new IllegalStateException(String.format("Cannot start process '%s' because it has already been started", displayName));
}
setState(ExecHandleState.STARTING);
execHandleRunner = new ExecHandleRunner(this, streamsHandler, processLauncher);
executor.execute(execHandleRunner);
while(stateIn(ExecHandleState.STARTING)) {
LOGGER.debug("Waiting until process started: {}.", displayName);
try {
condition.await();
} catch (InterruptedException e) {
//ok, wrapping up
}
}
if (execResult != null) {
execResult.rethrowFailure();
}
LOGGER.info("Successfully started process '{}'", displayName);
} finally {
lock.unlock();
}
return this;
}
public void abort() {
lock.lock();
try {
if (state == ExecHandleState.SUCCEEDED) {
return;
}
if (!stateIn(ExecHandleState.STARTED, ExecHandleState.DETACHED)) {
throw new IllegalStateException(String.format("Cannot abort process '%s' because it is not in started or detached state", displayName));
}
this.execHandleRunner.abortProcess();
} finally {
lock.unlock();
}
}
public ExecResult waitForFinish() {
lock.lock();
try {
while (!stateIn(ExecHandleState.SUCCEEDED, ExecHandleState.ABORTED, ExecHandleState.FAILED, ExecHandleState.DETACHED)) {
try {
condition.await();
} catch (InterruptedException e) {
//ok, wrapping up...
}
}
} finally {
lock.unlock();
}
executor.stop();
return result();
}
private ExecResult result() {
lock.lock();
try {
execResult.rethrowFailure();
return execResult;
} finally {
lock.unlock();
}
}
void detached() {
setEndStateInfo(ExecHandleState.DETACHED, 0, null);
}
void started() {
ShutdownHookActionRegister.addAction(shutdownHookAction);
setState(ExecHandleState.STARTED);
broadcast.getSource().executionStarted(this);
}
void finished(int exitCode) {
if (exitCode != 0) {
setEndStateInfo(ExecHandleState.FAILED, exitCode, null);
} else {
setEndStateInfo(ExecHandleState.SUCCEEDED, 0, null);
}
}
void aborted(int exitCode) {
if (exitCode == 0) {
// This can happen on Windows
exitCode = -1;
}
setEndStateInfo(ExecHandleState.ABORTED, exitCode, null);
}
void failed(Throwable failureCause) {
setEndStateInfo(ExecHandleState.FAILED, -1, failureCause);
}
public void addListener(ExecHandleListener listener) {
broadcast.add(listener);
}
public void removeListener(ExecHandleListener listener) {
broadcast.remove(listener);
}
public String getDisplayName() {
return displayName;
}
public boolean getRedirectErrorStream() {
return redirectErrorStream;
}
public int getTimeout() {
return timeoutMillis;
}
private static class ExecResultImpl implements ExecResult {
private final int exitValue;
private final ExecException failure;
private final String displayName;
public ExecResultImpl(int exitValue, ExecException failure, String displayName) {
this.exitValue = exitValue;
this.failure = failure;
this.displayName = displayName;
}
public int getExitValue() {
return exitValue;
}
public ExecResult assertNormalExitValue() throws ExecException {
if (exitValue != 0) {
throw new ExecException(String.format("Process '%s' finished with non-zero exit value %d", displayName, exitValue));
}
return this;
}
public ExecResult rethrowFailure() throws ExecException {
if (failure != null) {
throw failure;
}
return this;
}
@Override
public String toString() {
return "{exitValue=" + exitValue + ", failure=" + failure + "}";
}
}
}