Add a framework for prefetching input files (in case they come from remote file systems).

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MOS_MIGRATED_REVID=131280794

1 files changed, 27 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/exec/ActionInputPrefetcher.java b/src/main/java/com/google/devtools/build/lib/exec/ActionInputPrefetcher.java
new file mode 100644
index 0000000000..84eb09a45f
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/exec/ActionInputPrefetcher.java
@@ -0,0 +1,27 @@
+// 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.exec;
+
+import com.google.devtools.build.lib.actions.ActionInput;
+
+/** Prefetches files to local disk. */
+public interface ActionInputPrefetcher {
+
+  /**
+   * Initiates best-effort prefetching of the given input. This should not block.
+   *
+   * <p>If the path is not under this prefetcher's control, the call should be a no-op.
+   */
+  void prefetchFile(ActionInput input);
+}