Fix #1849: Sandboxing on OS X should be turned off by default for 0.3.2.

This restructures the way we set the default Spawn strategy so that each BlazeModule supplying a SpawnActionContext has an ActionContextConsumer that sets its own SpawnActionContext as the default, with the BazelRulesModule being put as the last module loaded in BazelMain, so that it can override that decision - it only does, if the user explicitly specifies a --spawn_strategy flag. IMHO this is a much saner approach than the older one.

So the flow is essentially this:
- StandaloneActionContextConsumer sets the default strategy to "standalone".
- SandboxActionContextConsumer sets the default strategy to "sandboxed", but only on Linux
- BazelRulesModule sets the default strategy to the value of the --spawn_strategy flag, if it is set.

--
MOS_MIGRATED_REVID=134770427

6 files changed, 148 insertions, 63 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/bazel/BazelMain.java b/src/main/java/com/google/devtools/build/lib/bazel/BazelMain.java
index 844710c4e7..29e598659d 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/BazelMain.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/BazelMain.java
@@ -18,7 +18,6 @@ import com.google.common.collect.ImmutableMap;
 import com.google.devtools.build.lib.analysis.BlazeVersionInfo;
 import com.google.devtools.build.lib.runtime.BlazeModule;
 import com.google.devtools.build.lib.runtime.BlazeRuntime;
-
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.List;
@@ -43,13 +42,13 @@ public final class BazelMain {
           com.google.devtools.build.lib.bazel.BazelDiffAwarenessModule.class,
           com.google.devtools.build.lib.bazel.BazelRepositoryModule.class,
           com.google.devtools.build.lib.bazel.dash.DashModule.class,
-          com.google.devtools.build.lib.bazel.rules.BazelRulesModule.class,
           com.google.devtools.build.lib.ssd.SsdModule.class,
           com.google.devtools.build.lib.worker.WorkerModule.class,
           com.google.devtools.build.lib.remote.RemoteModule.class,
           com.google.devtools.build.lib.standalone.StandaloneModule.class,
           com.google.devtools.build.lib.sandbox.SandboxModule.class,
-          com.google.devtools.build.lib.runtime.BuildSummaryStatsModule.class);
+          com.google.devtools.build.lib.runtime.BuildSummaryStatsModule.class,
+          com.google.devtools.build.lib.bazel.rules.BazelRulesModule.class);
 
   public static void main(String[] args) {
     BlazeVersionInfo.setBuildInfo(tryGetBuildInfo());
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/BazelActionContextConsumer.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/BazelActionContextConsumer.java
new file mode 100644
index 0000000000..d9db7e4a00
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/BazelActionContextConsumer.java
@@ -0,0 +1,81 @@
+// Copyright 2016 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.bazel.rules;
+
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.ImmutableMultimap;
+import com.google.common.collect.Multimap;
+import com.google.devtools.build.lib.actions.ActionContextConsumer;
+import com.google.devtools.build.lib.actions.Executor.ActionContext;
+import com.google.devtools.build.lib.analysis.actions.FileWriteActionContext;
+import com.google.devtools.build.lib.bazel.rules.BazelRulesModule.BazelExecutionOptions;
+import com.google.devtools.build.lib.rules.android.WriteAdbArgsActionContext;
+import com.google.devtools.build.lib.rules.cpp.CppCompileActionContext;
+import com.google.devtools.build.lib.rules.cpp.CppLinkActionContext;
+import com.google.devtools.build.lib.rules.cpp.IncludeScanningContext;
+import java.util.Map;
+import java.util.TreeMap;
+
+/**
+ * An object describing the {@link ActionContext} implementation that some actions require in Bazel.
+ */
+public class BazelActionContextConsumer implements ActionContextConsumer {
+  private final BazelExecutionOptions options;
+
+  protected BazelActionContextConsumer(BazelExecutionOptions options) {
+    this.options = options;
+  }
+
+  @Override
+  public ImmutableMap<String, String> getSpawnActionContexts() {
+    Map<String, String> contexts = new TreeMap<>(String.CASE_INSENSITIVE_ORDER);
+
+    // Default strategies for certain mnemonics - they can be overridden by --strategy= flags.
+    contexts.put("Javac", "worker");
+
+    for (Map.Entry<String, String> strategy : options.strategy) {
+      String strategyName = strategy.getValue();
+      // TODO(philwo) - remove this when the standalone / local mess is cleaned up.
+      // Some flag expansions use "local" as the strategy name, but the strategy is now called
+      // "standalone", so we'll translate it here.
+      if (strategyName.equals("local")) {
+        strategyName = "standalone";
+      }
+      contexts.put(strategy.getKey(), strategyName);
+    }
+
+    if (!options.genruleStrategy.isEmpty()) {
+      contexts.put("Genrule", options.genruleStrategy);
+    }
+
+    // TODO(bazel-team): put this in getActionContexts (key=SpawnActionContext.class) instead
+    if (!options.spawnStrategy.isEmpty()) {
+      contexts.put("", options.spawnStrategy);
+    }
+
+    return ImmutableMap.copyOf(contexts);
+  }
+
+  @Override
+  public Multimap<Class<? extends ActionContext>, String> getActionContexts() {
+    return ImmutableMultimap.<Class<? extends ActionContext>, String>builder()
+        .put(CppCompileActionContext.class, "")
+        .put(CppLinkActionContext.class, "")
+        .put(IncludeScanningContext.class, "")
+        .put(FileWriteActionContext.class, "")
+        .put(WriteAdbArgsActionContext.class, "")
+        .build();
+  }
+}
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/BazelRulesModule.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/BazelRulesModule.java
index 26fd3af4b5..0fe4aa2a4a 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/BazelRulesModule.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/BazelRulesModule.java
@@ -16,25 +16,17 @@ package com.google.devtools.build.lib.bazel.rules;
 
 import com.google.common.base.Supplier;
 import com.google.common.collect.ImmutableList;
-import com.google.common.collect.ImmutableMap;
-import com.google.common.collect.ImmutableMultimap;
-import com.google.common.collect.Multimap;
 import com.google.common.eventbus.Subscribe;
 import com.google.devtools.build.lib.actions.ActionContextConsumer;
 import com.google.devtools.build.lib.actions.ActionContextProvider;
-import com.google.devtools.build.lib.actions.Executor.ActionContext;
 import com.google.devtools.build.lib.actions.SimpleActionContextProvider;
 import com.google.devtools.build.lib.analysis.BlazeDirectories;
 import com.google.devtools.build.lib.analysis.ConfiguredRuleClassProvider;
-import com.google.devtools.build.lib.analysis.actions.FileWriteActionContext;
 import com.google.devtools.build.lib.bazel.rules.cpp.BazelCppRuleClasses;
 import com.google.devtools.build.lib.query2.output.OutputFormatter;
 import com.google.devtools.build.lib.rules.android.WriteAdbArgsActionContext;
-import com.google.devtools.build.lib.rules.cpp.CppCompileActionContext;
-import com.google.devtools.build.lib.rules.cpp.CppLinkActionContext;
 import com.google.devtools.build.lib.rules.cpp.FdoSupportFunction;
 import com.google.devtools.build.lib.rules.cpp.FdoSupportValue;
-import com.google.devtools.build.lib.rules.cpp.IncludeScanningContext;
 import com.google.devtools.build.lib.rules.genquery.GenQuery;
 import com.google.devtools.build.lib.runtime.BlazeModule;
 import com.google.devtools.build.lib.runtime.Command;
@@ -49,7 +41,6 @@ import com.google.devtools.common.options.OptionsBase;
 import java.io.IOException;
 import java.util.List;
 import java.util.Map;
-import java.util.TreeMap;
 
 /**
  * Module implementing the rule set of Bazel.
@@ -92,54 +83,6 @@ public class BazelRulesModule extends BlazeModule {
     public List<Map.Entry<String, String>> strategy;
   }
 
-  /**
-   * An object describing the {@link ActionContext} implementation that some actions require in
-   * Bazel.
-   */
-  protected static class BazelActionContextConsumer implements ActionContextConsumer {
-    private final BazelExecutionOptions options;
-
-    protected BazelActionContextConsumer(BazelExecutionOptions options) {
-      this.options = options;
-    }
-    @Override
-    public ImmutableMap<String, String> getSpawnActionContexts() {
-      Map<String, String> contexts = new TreeMap<>(String.CASE_INSENSITIVE_ORDER);
-
-      // Default strategies for certain mnemonics - they can be overridden by --strategy= flags.
-      contexts.put("Javac", "worker");
-
-      contexts.put("Genrule", options.genruleStrategy);
-
-      for (Map.Entry<String, String> strategy : options.strategy) {
-        String strategyName = strategy.getValue();
-        // TODO(philwo) - remove this when the standalone / local mess is cleaned up.
-        // Some flag expansions use "local" as the strategy name, but the strategy is now called
-        // "standalone", so we'll translate it here.
-        if (strategyName.equals("local")) {
-          strategyName = "standalone";
-        }
-        contexts.put(strategy.getKey(), strategyName);
-      }
-
-      // TODO(bazel-team): put this in getActionContexts (key=SpawnActionContext.class) instead
-      contexts.put("", options.spawnStrategy);
-
-      return ImmutableMap.copyOf(contexts);
-    }
-
-    @Override
-    public Multimap<Class<? extends ActionContext>, String> getActionContexts() {
-      return ImmutableMultimap.<Class<? extends ActionContext>, String>builder()
-          .put(CppCompileActionContext.class, "")
-          .put(CppLinkActionContext.class, "")
-          .put(IncludeScanningContext.class, "")
-          .put(FileWriteActionContext.class, "")
-          .put(WriteAdbArgsActionContext.class, "")
-          .build();
-    }
-  }
-
   private CommandEnvironment env;
   protected BazelExecutionOptions options;
 
@@ -170,8 +113,7 @@ public class BazelRulesModule extends BlazeModule {
 
   @Override
   public Iterable<ActionContextConsumer> getActionContextConsumers() {
-    return ImmutableList.<ActionContextConsumer>of(
-        new BazelActionContextConsumer(options));
+    return ImmutableList.<ActionContextConsumer>of(new BazelActionContextConsumer(options));
   }
 
   @Subscribe
diff --git a/src/main/java/com/google/devtools/build/lib/sandbox/SandboxActionContextConsumer.java b/src/main/java/com/google/devtools/build/lib/sandbox/SandboxActionContextConsumer.java
index cd468fd1f9..403b8b9837 100644
--- a/src/main/java/com/google/devtools/build/lib/sandbox/SandboxActionContextConsumer.java
+++ b/src/main/java/com/google/devtools/build/lib/sandbox/SandboxActionContextConsumer.java
@@ -30,22 +30,33 @@ import com.google.devtools.build.lib.util.OS;
 final class SandboxActionContextConsumer implements ActionContextConsumer {
 
   private final ImmutableMultimap<Class<? extends ActionContext>, String> contexts;
+  private final ImmutableMap<String, String> spawnContexts;
 
   public SandboxActionContextConsumer(CommandEnvironment env) {
     ImmutableMultimap.Builder<Class<? extends ActionContext>, String> contexts =
         ImmutableMultimap.builder();
+    ImmutableMap.Builder<String, String> spawnContexts = ImmutableMap.builder();
 
+    // This makes the "sandboxed" strategy available via --spawn_strategy=sandboxed,
+    // but it is not necessarily the default.
     if ((OS.getCurrent() == OS.LINUX && LinuxSandboxedStrategy.isSupported(env))
         || (OS.getCurrent() == OS.DARWIN && DarwinSandboxRunner.isSupported())) {
       contexts.put(SpawnActionContext.class, "sandboxed");
+
+      // This makes the "sandboxed" strategy the default Spawn strategy on Linux, unless it is
+      // overridden by a later BlazeModule.
+      if (OS.getCurrent() == OS.LINUX) {
+        spawnContexts.put("", "sandboxed");
+      }
     }
 
     this.contexts = contexts.build();
+    this.spawnContexts = spawnContexts.build();
   }
 
   @Override
   public ImmutableMap<String, String> getSpawnActionContexts() {
-    return ImmutableMap.of();
+    return spawnContexts;
   }
 
   @Override
diff --git a/src/main/java/com/google/devtools/build/lib/standalone/StandaloneActionContextConsumer.java b/src/main/java/com/google/devtools/build/lib/standalone/StandaloneActionContextConsumer.java
new file mode 100644
index 0000000000..beb1125475
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/standalone/StandaloneActionContextConsumer.java
@@ -0,0 +1,44 @@
+// Copyright 2016 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.collect.ImmutableMultimap;
+import com.google.common.collect.Multimap;
+import com.google.devtools.build.lib.actions.ActionContextConsumer;
+import com.google.devtools.build.lib.actions.Executor.ActionContext;
+import com.google.devtools.build.lib.actions.SpawnActionContext;
+
+/**
+ * {@link ActionContextConsumer} that requests the action contexts necessary for standalone
+ * execution.
+ */
+public class StandaloneActionContextConsumer implements ActionContextConsumer {
+
+  @Override
+  public ImmutableMap<String, String> getSpawnActionContexts() {
+    // This makes the "sandboxed" strategy the default Spawn strategy, unless it is overridden by a
+    // later BlazeModule.
+    return ImmutableMap.of("", "standalone");
+  }
+
+  @Override
+  public Multimap<Class<? extends ActionContext>, String> getActionContexts() {
+    // This makes the "standalone" strategy available via --spawn_strategy=standalone, but it is not
+    // necessarily the default.
+    return ImmutableMultimap.<Class<? extends ActionContext>, String>of(
+        SpawnActionContext.class, "standalone");
+  }
+}
diff --git a/src/main/java/com/google/devtools/build/lib/standalone/StandaloneModule.java b/src/main/java/com/google/devtools/build/lib/standalone/StandaloneModule.java
index a8118ea367..58145b0ad3 100644
--- a/src/main/java/com/google/devtools/build/lib/standalone/StandaloneModule.java
+++ b/src/main/java/com/google/devtools/build/lib/standalone/StandaloneModule.java
@@ -15,12 +15,14 @@ package com.google.devtools.build.lib.standalone;
 
 import com.google.common.collect.ImmutableList;
 import com.google.common.eventbus.Subscribe;
+import com.google.devtools.build.lib.actions.ActionContextConsumer;
 import com.google.devtools.build.lib.actions.ActionContextProvider;
 import com.google.devtools.build.lib.buildtool.BuildRequest;
 import com.google.devtools.build.lib.buildtool.buildevent.BuildStartingEvent;
 import com.google.devtools.build.lib.runtime.BlazeModule;
 import com.google.devtools.build.lib.runtime.Command;
 import com.google.devtools.build.lib.runtime.CommandEnvironment;
+import com.google.devtools.build.lib.util.Preconditions;
 
 /**
  * StandaloneModule provides pluggable functionality for blaze.
@@ -30,6 +32,12 @@ public class StandaloneModule extends BlazeModule {
   private BuildRequest buildRequest;
 
   @Override
+  public Iterable<ActionContextConsumer> getActionContextConsumers() {
+    Preconditions.checkNotNull(env);
+    return ImmutableList.<ActionContextConsumer>of(new StandaloneActionContextConsumer());
+  }
+
+  @Override
   public Iterable<ActionContextProvider> getActionContextProviders() {
     return ImmutableList.<ActionContextProvider>of(
         new StandaloneActionContextProvider(env, buildRequest));