Rollback of commit 2891ec527eed27d0c6460d66f51cb66a43373b6a.

*** Reason for rollback ***

Causes our integration tests on Darwin to time out

*** Original change description ***

Make --watchfs a common command option.

Adding an options parameter to DiffAwareness#getCurrentView seems like the
simplest way to achieve that.

Alternatives considered:
1. Making the diff awareness modules stateful. However, I did not want to do so
as I've also been working on improving the module API to reduce state, or at
least to have a proper lifecycle management for any necessary state.

2. Making the watchFs flag a constructor parameter. However, that would also
invalidate any implement...

***

--
MOS_MIGRATED_REVID=136070807

1 files changed, 17 insertions, 54 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/MacOSXFsEventsDiffAwareness.java b/src/main/java/com/google/devtools/build/lib/skyframe/MacOSXFsEventsDiffAwareness.java
index f56611aca3..cf0fc621b5 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/MacOSXFsEventsDiffAwareness.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/MacOSXFsEventsDiffAwareness.java
@@ -17,7 +17,7 @@ package com.google.devtools.build.lib.skyframe;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableSet;
 import com.google.devtools.build.lib.UnixJniLoader;
-import com.google.devtools.common.options.OptionsClassProvider;
+
 import java.io.File;
 import java.nio.file.Path;
 
@@ -25,11 +25,11 @@ import java.nio.file.Path;
  * A {@link DiffAwareness} that use fsevents to watch the filesystem to use in lieu of
  * {@link LocalDiffAwareness}.
  *
- * <p>On OS X, the local diff awareness cannot work because WatchService is dummy and do polling,
- * which is slow (https://bugs.openjdk.java.net/browse/JDK-7133447).
+ * <p>
+ * On OS X, the local diff awareness cannot work because WatchService is dummy and do polling, which
+ * is slow (https://bugs.openjdk.java.net/browse/JDK-7133447).
  */
 public final class MacOSXFsEventsDiffAwareness extends LocalDiffAwareness {
-  private final double latency;
 
   private boolean closed;
 
@@ -37,15 +37,23 @@ public final class MacOSXFsEventsDiffAwareness extends LocalDiffAwareness {
   // structure).
   private long nativePointer;
 
-  private boolean opened;
-
   /**
    * Watch changes on the file system under <code>watchRoot</code> with a granularity of
    * <code>delay</code> seconds.
    */
   MacOSXFsEventsDiffAwareness(String watchRoot, double latency) {
     super(watchRoot);
-    this.latency = latency;
+    create(new String[] {watchRootPath.toAbsolutePath().toString()}, latency);
+
+    // Start a thread that just contains the OS X run loop.
+    new Thread(
+            new Runnable() {
+              @Override
+              public void run() {
+                MacOSXFsEventsDiffAwareness.this.run();
+              }
+            })
+        .start();
   }
 
   /**
@@ -65,35 +73,15 @@ public final class MacOSXFsEventsDiffAwareness extends LocalDiffAwareness {
    */
   private native void run();
 
-  private void init() {
-    // The code below is based on the assumption that init() can never fail, which is currently the
-    // case; if you change init(), then you also need to update {@link #getCurrentView}.
-    Preconditions.checkState(!opened);
-    opened = true;
-    create(new String[] {watchRootPath.toAbsolutePath().toString()}, latency);
-    // Start a thread that just contains the OS X run loop.
-    new Thread(
-            new Runnable() {
-              @Override
-              public void run() {
-                MacOSXFsEventsDiffAwareness.this.run();
-              }
-            })
-        .start();
-  }
-
   /**
    * Close this watch service, this service should not be used any longer after closing.
    */
-  @Override
   public synchronized void close() {
     Preconditions.checkState(!closed);
     closed = true;
     doClose();
   }
 
-  private static final boolean JNI_AVAILABLE;
-
   /**
    * JNI code stopping the main loop and shutting down listening to FSEvents.
    */
@@ -105,36 +93,11 @@ public final class MacOSXFsEventsDiffAwareness extends LocalDiffAwareness {
   private native String[] poll();
 
   static {
-    boolean loadJniWorked = false;
-    try {
-      UnixJniLoader.loadJni();
-      loadJniWorked = true;
-    } catch (UnsatisfiedLinkError ignored) {
-      // Unfortunately, we compile this class into the Bazel bootstrap binary, which doesn't have
-      // access to the JNI code (to simplify bootstrap). This is the quick and dirty way to
-      // hard-disable --watchfs in the bootstrap binary.
-    }
-    JNI_AVAILABLE = loadJniWorked;
+    UnixJniLoader.loadJni();
   }
 
   @Override
-  public synchronized View getCurrentView(OptionsClassProvider options)
-      throws BrokenDiffAwarenessException {
-    if (!JNI_AVAILABLE) {
-      return EVERYTHING_MODIFIED;
-    }
-    // See WatchServiceDiffAwareness#getCurrentView for an explanation of this logic.
-    boolean watchFs = options.getOptions(Options.class).watchFS;
-    if (watchFs && !opened) {
-      init();
-    } else if (!watchFs && opened) {
-      close();
-      throw new BrokenDiffAwarenessException("Switched off --watchfs again");
-    } else if (!opened) {
-      // The only difference with WatchServiceDiffAwareness#getCurrentView is this if; the init()
-      // call above can never fail, so we don't need to re-check the opened flag after init().
-      return EVERYTHING_MODIFIED;
-    }
+  public synchronized View getCurrentView() throws BrokenDiffAwarenessException {
     Preconditions.checkState(!closed);
     ImmutableSet.Builder<Path> paths = ImmutableSet.builder();
     for (String path : poll()) {