src/main/java/com/google/devtools/build/lib/actions/MutableActionGraph.java - bazel - Git at Google

 // 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.actions;

 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Sets;
 import com.google.common.collect.Sets.SetView;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.events.Event;
 import com.google.devtools.build.lib.events.EventHandler;
 import java.util.Set;

 /**
  * A mutable action graph. Implementations of this interface must be thread-safe.
  */
 public interface MutableActionGraph extends ActionGraph {

   /**
    * Attempts to register the action. If any of the action's outputs already has a generating
    * action, and the two actions are not compatible, then an {@link ActionConflictException} is
    * thrown. The internal data structure may be partially modified when that happens; it is not
    * guaranteed that all potential conflicts are detected, but at least one of them is.
    *
    * <p>For example, take three actions A, B, and C, where A creates outputs a and b, B creates just
    * b, and C creates c and b. There are two potential conflicts in this case, between A and B, and
    * between B and C. Depending on the ordering of calls to this method and the ordering of outputs
    * in the action output lists, either one or two conflicts are detected: if B is registered first,
    * then both conflicts are detected; if either A or C is registered first, then only one conflict
    * is detected.
    */
   void registerAction(ActionAnalysisMetadata action) throws ActionConflictException;

   /**
    * Removes an action from this action graph if it is present.
    *
    * <p>Throws {@link IllegalStateException} if one of the outputs of the action is in fact
    * generated by a different {@link Action} instance (even if they are sharable).
    */
   void unregisterAction(ActionAnalysisMetadata action);

   /**
    * Clear the action graph.
    */
   void clear();

   /**
    * This exception is thrown when a conflict between actions is detected. It contains information
    * about the artifact for which the conflict is found, and data about the two conflicting actions
    * and their owners.
    */
   final class ActionConflictException extends Exception {

     private final Artifact artifact;
     private final String suffix;

     private static final int MAX_DIFF_ARTIFACTS_TO_REPORT = 5;

     public ActionConflictException(
         ActionKeyContext actionKeyContext,
         Artifact artifact,
         ActionAnalysisMetadata previousAction,
         ActionAnalysisMetadata attemptedAction) {
       super(
           String.format(
               "for %s, previous action: %s, attempted action: %s",
               artifact.prettyPrint(),
               previousAction.prettyPrint(),
               attemptedAction.prettyPrint()));
       this.artifact = artifact;
       this.suffix = suffix(actionKeyContext, attemptedAction, previousAction);
     }

     public Artifact getArtifact() {
       return artifact;
     }

     public void reportTo(EventHandler eventListener) {
       String msg =
           "file '"
               + artifact.prettyPrint()
               + "' is generated by these conflicting actions:\n"
               + suffix;
       eventListener.handle(Event.error(msg));
     }

     private static void addStringDetail(
         StringBuilder sb, String key, String valueA, String valueB) {
       valueA = valueA != null ? valueA : "(null)";
       valueB = valueB != null ? valueB : "(null)";

       sb.append(key).append(": ").append(valueA);
       if (!valueA.equals(valueB)) {
         sb.append(", ").append(valueB);
       }
       sb.append("\n");
     }

     private static void addListDetail(
         StringBuilder sb, String key, Iterable<Artifact> valueA, Iterable<Artifact> valueB) {
       Set<Artifact> setA = ImmutableSet.copyOf(valueA);
       Set<Artifact> setB = ImmutableSet.copyOf(valueB);
       SetView<Artifact> diffA = Sets.difference(setA, setB);
       SetView<Artifact> diffB = Sets.difference(setB, setA);

       sb.append(key).append(": ");
       if (diffA.isEmpty() && diffB.isEmpty()) {
         sb.append("are equal\n");
       } else {
         if (!diffA.isEmpty()) {
           sb.append(
               "Attempted action contains artifacts not in previous action (first "
                   + MAX_DIFF_ARTIFACTS_TO_REPORT
                   + "): \n");
           prettyPrintArtifactDiffs(sb, diffA);
         }

         if (!diffB.isEmpty()) {
           sb.append(
               "Previous action contains artifacts not in attempted action (first "
                   + MAX_DIFF_ARTIFACTS_TO_REPORT
                   + "): \n");
           prettyPrintArtifactDiffs(sb, diffB);
         }
       }
     }

     /** Pretty print action diffs (at most {@code MAX_DIFF_ARTIFACTS_TO_REPORT} lines). */
     private static void prettyPrintArtifactDiffs(StringBuilder sb, SetView<Artifact> diff) {
       for (Artifact artifact : Iterables.limit(diff, MAX_DIFF_ARTIFACTS_TO_REPORT)) {
         sb.append("\t" + artifact.prettyPrint() + "\n");
       }
     }

     private static String getKey(ActionKeyContext actionKeyContext, ActionAnalysisMetadata action) {
       return action instanceof Action ? ((Action) action).getKey(actionKeyContext) : null;
     }

     // See also Actions.canBeShared()
     private static String suffix(
         ActionKeyContext actionKeyContext, ActionAnalysisMetadata a, ActionAnalysisMetadata b) {
       // Note: the error message reveals to users the names of intermediate files that are not
       // documented in the BUILD language.  This error-reporting logic is rather elaborate but it
       // does help to diagnose some tricky situations.
       StringBuilder sb = new StringBuilder();
       ActionOwner aOwner = a.getOwner();
       ActionOwner bOwner = b.getOwner();
       boolean aNull = aOwner == null;
       boolean bNull = bOwner == null;

       addStringDetail(sb, "Label", aNull ? null : Label.print(aOwner.getLabel()),
           bNull ? null : Label.print(bOwner.getLabel()));
       addStringDetail(sb, "RuleClass", aNull ? null : aOwner.getTargetKind(),
           bNull ? null : bOwner.getTargetKind());
       addStringDetail(sb, "Configuration", aNull ? null : aOwner.getConfigurationChecksum(),
           bNull ? null : bOwner.getConfigurationChecksum());
       addStringDetail(sb, "Mnemonic", a.getMnemonic(), b.getMnemonic());
       addStringDetail(sb, "Action key", getKey(actionKeyContext, a), getKey(actionKeyContext, b));

       if ((a instanceof ActionExecutionMetadata) && (b instanceof ActionExecutionMetadata)) {
         addStringDetail(
             sb,
             "Progress message",
             ((ActionExecutionMetadata) a).getProgressMessage(),
             ((ActionExecutionMetadata) b).getProgressMessage());
       }

       Artifact aPrimaryInput = a.getPrimaryInput();
       Artifact bPrimaryInput = b.getPrimaryInput();
       addStringDetail(
           sb,
           "PrimaryInput",
           aPrimaryInput == null ? null : aPrimaryInput.toString(),
           bPrimaryInput == null ? null : bPrimaryInput.toString());
       addStringDetail(
           sb, "PrimaryOutput", a.getPrimaryOutput().toString(), b.getPrimaryOutput().toString());

       // Only add list details if the primary input of A matches the input of B. Otherwise
       // the above information is enough and list diff detail is not needed.
       if ((aPrimaryInput == null && bPrimaryInput == null)
           || (aPrimaryInput != null
               && bPrimaryInput != null
               && aPrimaryInput.toString().equals(bPrimaryInput.toString()))) {
         Artifact aPrimaryOutput = a.getPrimaryOutput();
         Artifact bPrimaryOutput = b.getPrimaryOutput();
         if (!aPrimaryOutput.equals(bPrimaryOutput)) {
           sb.append("Primary outputs are different: ")
               .append(System.identityHashCode(aPrimaryOutput))
               .append(", ")
               .append(System.identityHashCode(bPrimaryOutput))
               .append('\n');
         }
         ArtifactOwner aArtifactOwner = aPrimaryOutput.getArtifactOwner();
         ArtifactOwner bArtifactOwner = bPrimaryOutput.getArtifactOwner();
         addStringDetail(
             sb, "Owner information", aArtifactOwner.toString(), bArtifactOwner.toString());
         addListDetail(sb, "MandatoryInputs", a.getMandatoryInputs(), b.getMandatoryInputs());
         addListDetail(sb, "Outputs", a.getOutputs(), b.getOutputs());
       }

       return sb.toString();
     }
   }
 }
	// 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.actions;

	import com.google.common.collect.ImmutableSet;
	import com.google.common.collect.Iterables;
	import com.google.common.collect.Sets;
	import com.google.common.collect.Sets.SetView;
	import com.google.devtools.build.lib.cmdline.Label;
	import com.google.devtools.build.lib.events.Event;
	import com.google.devtools.build.lib.events.EventHandler;
	import java.util.Set;

	/**
	* A mutable action graph. Implementations of this interface must be thread-safe.
	*/
	public interface MutableActionGraph extends ActionGraph {

	/**
	* Attempts to register the action. If any of the action's outputs already has a generating
	* action, and the two actions are not compatible, then an {@link ActionConflictException} is
	* thrown. The internal data structure may be partially modified when that happens; it is not
	* guaranteed that all potential conflicts are detected, but at least one of them is.
	*
	* <p>For example, take three actions A, B, and C, where A creates outputs a and b, B creates just
	* b, and C creates c and b. There are two potential conflicts in this case, between A and B, and
	* between B and C. Depending on the ordering of calls to this method and the ordering of outputs
	* in the action output lists, either one or two conflicts are detected: if B is registered first,
	* then both conflicts are detected; if either A or C is registered first, then only one conflict
	* is detected.
	*/
	void registerAction(ActionAnalysisMetadata action) throws ActionConflictException;

	/**
	* Removes an action from this action graph if it is present.
	*
	* <p>Throws {@link IllegalStateException} if one of the outputs of the action is in fact
	* generated by a different {@link Action} instance (even if they are sharable).
	*/
	void unregisterAction(ActionAnalysisMetadata action);

	/**
	* Clear the action graph.
	*/
	void clear();

	/**
	* This exception is thrown when a conflict between actions is detected. It contains information
	* about the artifact for which the conflict is found, and data about the two conflicting actions
	* and their owners.
	*/
	final class ActionConflictException extends Exception {

	private final Artifact artifact;
	private final String suffix;

	private static final int MAX_DIFF_ARTIFACTS_TO_REPORT = 5;

	public ActionConflictException(
	ActionKeyContext actionKeyContext,
	Artifact artifact,
	ActionAnalysisMetadata previousAction,
	ActionAnalysisMetadata attemptedAction) {
	super(
	String.format(
	"for %s, previous action: %s, attempted action: %s",
	artifact.prettyPrint(),
	previousAction.prettyPrint(),
	attemptedAction.prettyPrint()));
	this.artifact = artifact;
	this.suffix = suffix(actionKeyContext, attemptedAction, previousAction);
	}

	public Artifact getArtifact() {
	return artifact;
	}

	public void reportTo(EventHandler eventListener) {
	String msg =
	"file '"
	+ artifact.prettyPrint()
	+ "' is generated by these conflicting actions:\n"
	+ suffix;
	eventListener.handle(Event.error(msg));
	}

	private static void addStringDetail(
	StringBuilder sb, String key, String valueA, String valueB) {
	valueA = valueA != null ? valueA : "(null)";
	valueB = valueB != null ? valueB : "(null)";

	sb.append(key).append(": ").append(valueA);
	if (!valueA.equals(valueB)) {
	sb.append(", ").append(valueB);
	}
	sb.append("\n");
	}

	private static void addListDetail(
	StringBuilder sb, String key, Iterable<Artifact> valueA, Iterable<Artifact> valueB) {
	Set<Artifact> setA = ImmutableSet.copyOf(valueA);
	Set<Artifact> setB = ImmutableSet.copyOf(valueB);
	SetView<Artifact> diffA = Sets.difference(setA, setB);
	SetView<Artifact> diffB = Sets.difference(setB, setA);

	sb.append(key).append(": ");
	if (diffA.isEmpty() && diffB.isEmpty()) {
	sb.append("are equal\n");
	} else {
	if (!diffA.isEmpty()) {
	sb.append(
	"Attempted action contains artifacts not in previous action (first "
	+ MAX_DIFF_ARTIFACTS_TO_REPORT
	+ "): \n");
	prettyPrintArtifactDiffs(sb, diffA);
	}

	if (!diffB.isEmpty()) {
	sb.append(
	"Previous action contains artifacts not in attempted action (first "
	+ MAX_DIFF_ARTIFACTS_TO_REPORT
	+ "): \n");
	prettyPrintArtifactDiffs(sb, diffB);
	}
	}
	}

	/** Pretty print action diffs (at most {@code MAX_DIFF_ARTIFACTS_TO_REPORT} lines). */
	private static void prettyPrintArtifactDiffs(StringBuilder sb, SetView<Artifact> diff) {
	for (Artifact artifact : Iterables.limit(diff, MAX_DIFF_ARTIFACTS_TO_REPORT)) {
	sb.append("\t" + artifact.prettyPrint() + "\n");
	}
	}

	private static String getKey(ActionKeyContext actionKeyContext, ActionAnalysisMetadata action) {
	return action instanceof Action ? ((Action) action).getKey(actionKeyContext) : null;
	}

	// See also Actions.canBeShared()
	private static String suffix(
	ActionKeyContext actionKeyContext, ActionAnalysisMetadata a, ActionAnalysisMetadata b) {
	// Note: the error message reveals to users the names of intermediate files that are not
	// documented in the BUILD language. This error-reporting logic is rather elaborate but it
	// does help to diagnose some tricky situations.
	StringBuilder sb = new StringBuilder();
	ActionOwner aOwner = a.getOwner();
	ActionOwner bOwner = b.getOwner();
	boolean aNull = aOwner == null;
	boolean bNull = bOwner == null;

	addStringDetail(sb, "Label", aNull ? null : Label.print(aOwner.getLabel()),
	bNull ? null : Label.print(bOwner.getLabel()));
	addStringDetail(sb, "RuleClass", aNull ? null : aOwner.getTargetKind(),
	bNull ? null : bOwner.getTargetKind());
	addStringDetail(sb, "Configuration", aNull ? null : aOwner.getConfigurationChecksum(),
	bNull ? null : bOwner.getConfigurationChecksum());
	addStringDetail(sb, "Mnemonic", a.getMnemonic(), b.getMnemonic());
	addStringDetail(sb, "Action key", getKey(actionKeyContext, a), getKey(actionKeyContext, b));

	if ((a instanceof ActionExecutionMetadata) && (b instanceof ActionExecutionMetadata)) {
	addStringDetail(
	sb,
	"Progress message",
	((ActionExecutionMetadata) a).getProgressMessage(),
	((ActionExecutionMetadata) b).getProgressMessage());
	}

	Artifact aPrimaryInput = a.getPrimaryInput();
	Artifact bPrimaryInput = b.getPrimaryInput();
	addStringDetail(
	sb,
	"PrimaryInput",
	aPrimaryInput == null ? null : aPrimaryInput.toString(),
	bPrimaryInput == null ? null : bPrimaryInput.toString());
	addStringDetail(
	sb, "PrimaryOutput", a.getPrimaryOutput().toString(), b.getPrimaryOutput().toString());

	// Only add list details if the primary input of A matches the input of B. Otherwise
	// the above information is enough and list diff detail is not needed.
	if ((aPrimaryInput == null && bPrimaryInput == null)
	\|\| (aPrimaryInput != null
	&& bPrimaryInput != null
	&& aPrimaryInput.toString().equals(bPrimaryInput.toString()))) {
	Artifact aPrimaryOutput = a.getPrimaryOutput();
	Artifact bPrimaryOutput = b.getPrimaryOutput();
	if (!aPrimaryOutput.equals(bPrimaryOutput)) {
	sb.append("Primary outputs are different: ")
	.append(System.identityHashCode(aPrimaryOutput))
	.append(", ")
	.append(System.identityHashCode(bPrimaryOutput))
	.append('\n');
	}
	ArtifactOwner aArtifactOwner = aPrimaryOutput.getArtifactOwner();
	ArtifactOwner bArtifactOwner = bPrimaryOutput.getArtifactOwner();
	addStringDetail(
	sb, "Owner information", aArtifactOwner.toString(), bArtifactOwner.toString());
	addListDetail(sb, "MandatoryInputs", a.getMandatoryInputs(), b.getMandatoryInputs());
	addListDetail(sb, "Outputs", a.getOutputs(), b.getOutputs());
	}

	return sb.toString();
	}
	}
	}