Correctly handle path encoding in DiskCacheLock.

The earlier fix in 6922734 is wrong on Linux, where the native encoding is indicated by the sun.jnu.encoding property, and could be something other than UTF-8.

Closes #23817.

PiperOrigin-RevId: 680947021
Change-Id: Idd52c1615de6edf423f59b62e364f0b7131f2d47

src/main/java/com/google/devtools/build/lib/remote/disk/DiskCacheLock.java

@@ -13,13 +13,14 @@
 // limitations under the License.
 package com.google.devtools.build.lib.remote.disk;
 
-import static com.google.devtools.build.lib.util.StringUtil.reencodeInternalToExternal;
+import static java.nio.charset.StandardCharsets.ISO_8859_1;
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.devtools.build.lib.vfs.Path;
 import java.io.IOException;
 import java.nio.channels.FileChannel;
 import java.nio.channels.FileLock;
+import java.nio.charset.Charset;
 import java.nio.file.StandardOpenOption;
 
 /** Manages shared or exclusive access to the disk cache by concurrent processes. */
@@ -59,7 +60,7 @@ private static DiskCacheLock get(Path path, boolean shared) throws IOException {
     FileChannel channel =
         FileChannel.open(
             // Correctly handle non-ASCII paths by converting from the internal string encoding.
-            java.nio.file.Path.of(reencodeInternalToExternal(path.getPathString())),
+            java.nio.file.Path.of(getPathStringForJavaIo(path)),
             StandardOpenOption.READ,
             StandardOpenOption.WRITE,
             StandardOpenOption.CREATE);
@@ -71,6 +72,12 @@ private static DiskCacheLock get(Path path, boolean shared) throws IOException {
     return new DiskCacheLock(channel, lock);
   }
 
+  private static String getPathStringForJavaIo(Path path) {
+    return new String(
+        path.getPathString().getBytes(ISO_8859_1),
+        Charset.forName(System.getProperty("sun.jnu.encoding"), ISO_8859_1));
+  }
+
   @VisibleForTesting
   boolean isShared() {
     return lock.isShared();