// Copyright 2014 The Bazel Authors. All rights reserved.
//
// 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.google.devtools.build.lib.standalone;
import com.google.common.collect.ImmutableMap;
import com.google.common.eventbus.EventBus;
import com.google.devtools.build.lib.actions.ActionExecutionContext;
import com.google.devtools.build.lib.actions.ActionExecutionMetadata;
import com.google.devtools.build.lib.actions.ActionStatusMessage;
import com.google.devtools.build.lib.actions.ExecException;
import com.google.devtools.build.lib.actions.ExecutionStrategy;
import com.google.devtools.build.lib.actions.Executor;
import com.google.devtools.build.lib.actions.ResourceManager;
import com.google.devtools.build.lib.actions.ResourceManager.ResourceHandle;
import com.google.devtools.build.lib.actions.Spawn;
import com.google.devtools.build.lib.actions.SpawnActionContext;
import com.google.devtools.build.lib.actions.Spawns;
import com.google.devtools.build.lib.actions.UserExecException;
import com.google.devtools.build.lib.rules.apple.AppleConfiguration;
import com.google.devtools.build.lib.rules.apple.AppleHostInfo;
import com.google.devtools.build.lib.rules.apple.DottedVersion;
import com.google.devtools.build.lib.shell.AbnormalTerminationException;
import com.google.devtools.build.lib.shell.Command;
import com.google.devtools.build.lib.shell.CommandException;
import com.google.devtools.build.lib.shell.TerminationStatus;
import com.google.devtools.build.lib.util.CommandFailureUtils;
import com.google.devtools.build.lib.util.OS;
import com.google.devtools.build.lib.util.OsUtils;
import com.google.devtools.build.lib.util.io.FileOutErr;
import com.google.devtools.build.lib.vfs.Path;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
/**
* Strategy that uses subprocessing to execute a process.
*/
@ExecutionStrategy(name = { "standalone", "local" }, contextType = SpawnActionContext.class)
public class StandaloneSpawnStrategy implements SpawnActionContext {
private final boolean verboseFailures;
private final Path processWrapper;
private final Path execRoot;
private final String productName;
private final ResourceManager resourceManager;
public StandaloneSpawnStrategy(Path execRoot, boolean verboseFailures, String productName) {
this(execRoot, verboseFailures, productName, ResourceManager.instance());
}
public StandaloneSpawnStrategy(
Path execRoot, boolean verboseFailures, String productName, ResourceManager resourceManager) {
this.verboseFailures = verboseFailures;
this.execRoot = execRoot;
this.processWrapper = execRoot.getRelative(
"_bin/process-wrapper" + OsUtils.executableExtension());
this.productName = productName;
this.resourceManager = resourceManager;
}
/**
* Executes the given {@code spawn}.
*/
@Override
public void exec(Spawn spawn,
ActionExecutionContext actionExecutionContext)
throws ExecException, InterruptedException {
EventBus eventBus = actionExecutionContext.getExecutor().getEventBus();
ActionExecutionMetadata owner = spawn.getResourceOwner();
eventBus.post(ActionStatusMessage.schedulingStrategy(owner));
try (ResourceHandle handle =
resourceManager.acquireResources(owner, spawn.getLocalResources())) {
eventBus.post(ActionStatusMessage.runningStrategy(owner, "standalone"));
actuallyExec(spawn, actionExecutionContext);
}
}
/**
* Executes the given {@code spawn}.
*/
private void actuallyExec(Spawn spawn,
ActionExecutionContext actionExecutionContext)
throws ExecException {
Executor executor = actionExecutionContext.getExecutor();
if (executor.reportsSubcommands()) {
executor.reportSubcommand(spawn);
}
int timeoutSeconds = Spawns.getTimeoutSeconds(spawn);
// We must wrap the subprocess with process-wrapper to kill the process tree.
// All actions therefore depend on the process-wrapper file. Since it's embedded,
// we don't bother with declaring it as an input.
List<String> args = new ArrayList<>();
if (OS.getCurrent() != OS.WINDOWS) {
// TODO(bazel-team): process-wrapper seems to work on Windows, but requires
// additional setup as it is an msys2 binary, so it needs msys2 DLLs on %PATH%.
// Disable it for now to make the setup easier and to avoid further PATH hacks.
// Ideally we should have a native implementation of process-wrapper for Windows.
args.add(processWrapper.getPathString());
args.add(Integer.toString(timeoutSeconds));
args.add("5"); /* kill delay: give some time to print stacktraces and whatnot. */
// TODO(bazel-team): use process-wrapper redirection so we don't have to
// pass test logs through the Java heap.
args.add("-"); /* stdout. */
args.add("-"); /* stderr. */
}
args.addAll(spawn.getArguments());
String cwd = executor.getExecRoot().getPathString();
Command cmd =
new Command(
args.toArray(new String[] {}),
locallyDeterminedEnv(execRoot, productName, spawn.getEnvironment()),
new File(cwd),
OS.getCurrent() == OS.WINDOWS && timeoutSeconds >= 0 ? timeoutSeconds * 1000 : -1);
FileOutErr outErr = actionExecutionContext.getFileOutErr();
try {
cmd.execute(
/* stdin */ new byte[] {},
Command.NO_OBSERVER,
outErr.getOutputStream(),
outErr.getErrorStream(),
/*killSubprocessOnInterrupt*/ true);
} catch (AbnormalTerminationException e) {
TerminationStatus status = e.getResult().getTerminationStatus();
boolean timedOut = !status.exited() && (
status.timedout() || status.getTerminatingSignal() == 14 /* SIGALRM */);
String message =
CommandFailureUtils.describeCommandFailure(
verboseFailures, spawn.getArguments(), spawn.getEnvironment(), cwd);
throw new UserExecException(String.format("%s: %s", message, e), timedOut);
} catch (CommandException e) {
String message = CommandFailureUtils.describeCommandFailure(
verboseFailures, spawn.getArguments(), spawn.getEnvironment(), cwd);
throw new UserExecException(message, e);
}
}
@Override
public String toString() {
return "standalone";
}
/**
* Adds to the given environment all variables that are dependent on system state of the host
* machine.
*
* <p>Admittedly, hermeticity is "best effort" in such cases; these environment values should be
* as tied to configuration parameters as possible.
*
* <p>For example, underlying iOS toolchains require that SDKROOT resolve to an absolute system
* path, but, when selecting which SDK to resolve, the version number comes from build
* configuration.
*
* @return the new environment, comprised of the old environment plus any new variables
* @throws UserExecException if any variables dependent on system state could not be resolved
*/
public static ImmutableMap<String, String> locallyDeterminedEnv(
Path execRoot, String productName, ImmutableMap<String, String> env)
throws UserExecException {
// TODO(bazel-team): Remove apple-specific logic from this class.
ImmutableMap.Builder<String, String> newEnvBuilder = ImmutableMap.builder();
newEnvBuilder.putAll(env);
// Empty developer dir indicates to use the system default.
// TODO(bazel-team): Bazel's view of the xcode version and developer dir
// should be explicitly set for build hermiticity.
String developerDir = "";
if (env.containsKey(AppleConfiguration.XCODE_VERSION_ENV_NAME)) {
developerDir =
getDeveloperDir(
execRoot, productName, env.get(AppleConfiguration.XCODE_VERSION_ENV_NAME));
newEnvBuilder.put("DEVELOPER_DIR", developerDir);
}
if (env.containsKey(AppleConfiguration.APPLE_SDK_VERSION_ENV_NAME)) {
// The Apple platform is needed to select the appropriate SDK.
if (!env.containsKey(AppleConfiguration.APPLE_SDK_PLATFORM_ENV_NAME)) {
throw new UserExecException("Could not resolve apple platform for determining SDK");
}
String iosSdkVersion = env.get(AppleConfiguration.APPLE_SDK_VERSION_ENV_NAME);
String appleSdkPlatform = env.get(AppleConfiguration.APPLE_SDK_PLATFORM_ENV_NAME);
newEnvBuilder.put(
"SDKROOT",
getSdkRootEnv(execRoot, productName, developerDir, iosSdkVersion, appleSdkPlatform));
}
return newEnvBuilder.build();
}
private static String getDeveloperDir(Path execRoot, String productName, String xcodeVersion)
throws UserExecException {
if (OS.getCurrent() != OS.DARWIN) {
throw new UserExecException(
"Cannot locate xcode developer directory on non-darwin operating system");
}
return AppleHostInfo.getDeveloperDir(execRoot, DottedVersion.fromString(xcodeVersion),
productName);
}
private static String getSdkRootEnv(
Path execRoot,
String productName,
String developerDir,
String iosSdkVersion,
String appleSdkPlatform)
throws UserExecException {
if (OS.getCurrent() != OS.DARWIN) {
throw new UserExecException("Cannot locate iOS SDK on non-darwin operating system");
}
return AppleHostInfo.getSdkRoot(execRoot, developerDir, iosSdkVersion, appleSdkPlatform,
productName);
}
@Override
public boolean shouldPropagateExecException() {
return false;
}
}