External repositories: support plain tar archives

Currently, we insist on all archives we download being compressed. But
technically, there is no reason compression is needed; handling plain
tar archives is no more complicated. So add that option as well; at the
very least, it makes testing more easy.

Change-Id: I1fddc95d5c80d195eb900ab74bf6403484f61da7
PiperOrigin-RevId: 182777193

2 files changed, 39 insertions, 1 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/bazel/repository/DecompressorValue.java b/src/main/java/com/google/devtools/build/lib/bazel/repository/DecompressorValue.java
index 02df7137ec..924a8791c4 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/repository/DecompressorValue.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/repository/DecompressorValue.java
@@ -55,6 +55,8 @@ public class DecompressorValue implements SkyValue {
     String baseName = archivePath.getBaseName();
     if (baseName.endsWith(".zip") || baseName.endsWith(".jar") || baseName.endsWith(".war")) {
       return ZipDecompressor.INSTANCE;
+    } else if (baseName.endsWith(".tar")) {
+      return TarFunction.INSTANCE;
     } else if (baseName.endsWith(".tar.gz") || baseName.endsWith(".tgz")) {
       return TarGzFunction.INSTANCE;
     } else if (baseName.endsWith(".tar.xz")) {
@@ -64,7 +66,7 @@ public class DecompressorValue implements SkyValue {
     } else {
       throw new RepositoryFunctionException(
           new EvalException(null, String.format(
-              "Expected a file with a .zip, .jar, .war, .tar.gz, .tgz, .tar.xz, or .tar.bz2 "
+              "Expected a file with a .zip, .jar, .war, .tar, .tar.gz, .tgz, .tar.xz, or .tar.bz2 "
               + "suffix (got %s)",
               archivePath)),
           Transience.PERSISTENT);
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/repository/TarFunction.java b/src/main/java/com/google/devtools/build/lib/bazel/repository/TarFunction.java
new file mode 100644
index 0000000000..e67f1ec1e1
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/bazel/repository/TarFunction.java
@@ -0,0 +1,36 @@
+// Copyright 2015 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.repository;
+
+import com.google.devtools.build.lib.bazel.repository.DecompressorValue.Decompressor;
+import java.io.BufferedInputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+
+/** Creates a repository by unarchiving a plain .tar file. */
+public class TarFunction extends CompressedTarFunction {
+  public static final Decompressor INSTANCE = new TarFunction();
+  private static final int BUFFER_SIZE = 32 * 1024;
+
+  private TarFunction() {}
+
+  @Override
+  protected InputStream getDecompressorStream(DecompressorDescriptor descriptor)
+      throws IOException {
+    return new BufferedInputStream(
+        new FileInputStream(descriptor.archivePath().getPathFile()), BUFFER_SIZE);
+  }
+}