Fixed the issue that hard links are handled improperly when bazel decompresses tarballs.

Issue link: https://github.com/bazelbuild/bazel/issues/574

--
MOS_MIGRATED_REVID=132434278

1 files changed, 21 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/vfs/UnionFileSystem.java b/src/main/java/com/google/devtools/build/lib/vfs/UnionFileSystem.java
index cf67d1e749..a0a09555f2 100644
--- a/src/main/java/com/google/devtools/build/lib/vfs/UnionFileSystem.java
+++ b/src/main/java/com/google/devtools/build/lib/vfs/UnionFileSystem.java
@@ -173,6 +173,11 @@ public class UnionFileSystem extends FileSystem {
   }
 
   @Override
+  public boolean supportsHardLinksNatively() {
+    return true;
+  }
+
+  @Override
   public boolean isFilePathCaseSensitive() {
     return this.isCaseSensitive;
   }
@@ -435,4 +440,20 @@ public class UnionFileSystem extends FileSystem {
       sourceDelegate.delete(sourcePath);
     }
   }
+
+  @Override
+  protected void createFSDependentHardLink(Path linkPath, Path originalPath)
+      throws IOException {
+    checkModifiable();
+
+    FileSystem originalDelegate = getDelegate(originalPath);
+    FileSystem linkDelegate = getDelegate(linkPath);
+
+    if (!originalDelegate.equals(linkDelegate) || !linkDelegate.supportsHardLinksNatively()) {
+      throw new UnsupportedOperationException(
+          "Attempted to create a hard link, but hard link support is disabled.");
+    }
+    linkDelegate.createFSDependentHardLink(
+        adjustPath(linkPath, linkDelegate), adjustPath(originalPath, originalDelegate));
+  }
 }