Remove pack from list when file handle is stale

This error happens on nfs file system when you try to read a file that
was deleted or replaced.

When the error happens because the file was deleted, removing it from
the list is the proper way to handle the error, same use case as
FileNotFoundException. When the error happens because the file was
replaced, removing the file from the list will cause the file to be
re-read so it will get the latest version of the file.

Bug: 462868
Change-Id: I368af61a6cf73706601a3e4df4ef24f0aa0465c5
Signed-off-by: Hugo Arès <hugo.ares@ericsson.com>

org.eclipse.jgit/resources/org/eclipse/jgit/internal/JGitText.properties

@@ -394,6 +394,7 @@ packfileCorruptionDetected=Packfile corruption detected: {0}
 packFileInvalid=Pack file invalid: {0}
 packfileIsTruncated=Packfile {0} is truncated.
 packfileIsTruncatedNoParam=Packfile is truncated.
+packHandleIsStale=Pack file {0} handle is stale, removing it from pack list
 packHasUnresolvedDeltas=pack has unresolved deltas
 packingCancelledDuringObjectsWriting=Packing cancelled during objects writing
 packObjectCountMismatch=Pack object count mismatch: pack {0} index {1}: {2}

org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java

@@ -453,6 +453,7 @@ public class JGitText extends TranslationBundle {
 	/***/ public String packFileInvalid;
 	/***/ public String packfileIsTruncated;
 	/***/ public String packfileIsTruncatedNoParam;
+	/***/ public String packHandleIsStale;
 	/***/ public String packHasUnresolvedDeltas;
 	/***/ public String packingCancelledDuringObjectsWriting;
 	/***/ public String packObjectCountMismatch;

org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/ObjectDirectory.java

@@ -114,6 +114,8 @@ public class ObjectDirectory extends FileObjectDatabase {
 	/** Maximum number of candidates offered as resolutions of abbreviation. */
 	private static final int RESOLVE_ABBREV_LIMIT = 256;
 
+	private static final String STALE_FILE_HANDLE_MSG = "stale file handle"; //$NON-NLS-1$
+
 	private final Config config;
 
 	private final File objects;
@@ -563,6 +565,10 @@ public class ObjectDirectory extends FileObjectDatabase {
 		} else if (e instanceof FileNotFoundException) {
 			warnTmpl = JGitText.get().packWasDeleted;
 			removePack(p);
+		} else if (e.getMessage() != null
+				&& e.getMessage().toLowerCase().contains(STALE_FILE_HANDLE_MSG)) {
+			warnTmpl = JGitText.get().packHandleIsStale;
+			removePack(p);
 		}
 		if (warnTmpl != null) {
 			if (LOG.isDebugEnabled()) {