Fix open file handle prevent deleting a repository on Windows (#2008)

Fixes the problem of unclosed file handles which occur when a repository or pack file is accessed (e.g. asynchronously in a post receive hook) after the file had already been closed. Such open file handle prevents deleting a repositories on Windows.

gradle/changelog/fix_open_file_handles.yaml

@@ -0,0 +1,2 @@
+- type: fixed
+  description: Open file handle prevent deleting a repository on Windows ([#2008](https://github.com/scm-manager/scm-manager/pull/2008))

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/GitHookChangesetCollector.java

@@ -29,7 +29,6 @@ package sonia.scm.repository;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
 
-import org.eclipse.jgit.errors.IncorrectObjectTypeException;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.revwalk.RevSort;
@@ -40,7 +39,6 @@ import org.eclipse.jgit.transport.ReceivePack;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import sonia.scm.util.IOUtil;
 import sonia.scm.web.CollectingPackParserListener;
 
 //~--- JDK imports ------------------------------------------------------------
@@ -92,16 +90,12 @@ public class GitHookChangesetCollector
   {
     Map<String, Changeset> changesets = Maps.newLinkedHashMap();
 
-    org.eclipse.jgit.lib.Repository repository = rpack.getRepository();
+    try (
-
+         org.eclipse.jgit.lib.Repository repository = rpack.getRepository();
-    RevWalk walk = null;
+         RevWalk walk = rpack.getRevWalk();
-
+         GitChangesetConverter converter = converterFactory.create(repository, walk)
-    GitChangesetConverter converter = null;
+    ) {
-
+      repository.incrementOpen();
-    try
-    {
-      walk = rpack.getRevWalk();
-      converter = converterFactory.create(repository, walk);
 
       for (ReceiveCommand rc : receiveCommands)
       {
@@ -142,18 +136,13 @@ public class GitHookChangesetCollector
     {
       logger.error("could not collect changesets", ex);
     }
-    finally
-    {
-      IOUtil.close(converter);
-      GitUtil.release(walk);
-    }
 
     return Lists.newArrayList(changesets.values());
   }
 
   private void collectChangesets(Map<String, Changeset> changesets,
     GitChangesetConverter converter, RevWalk walk, ReceiveCommand rc)
-    throws IncorrectObjectTypeException, IOException
+    throws IOException
   {
     ObjectId newId = rc.getNewId();
 

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/web/GitRepositoryResolver.java

@@ -30,16 +30,14 @@ import com.google.common.base.Preconditions;
 import com.google.inject.Inject;
 import org.eclipse.jgit.errors.RepositoryNotFoundException;
 import org.eclipse.jgit.lib.Repository;
-import org.eclipse.jgit.lib.RepositoryCache;
-import org.eclipse.jgit.lib.RepositoryCache.FileKey;
 import org.eclipse.jgit.transport.resolver.RepositoryResolver;
 import org.eclipse.jgit.transport.resolver.ServiceNotAuthorizedException;
 import org.eclipse.jgit.transport.resolver.ServiceNotEnabledException;
-import org.eclipse.jgit.util.FS;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import sonia.scm.repository.GitConfig;
 import sonia.scm.repository.GitRepositoryHandler;
+import sonia.scm.repository.GitUtil;
 import sonia.scm.repository.RepositoryProvider;
 
 import javax.servlet.http.HttpServletRequest;
@@ -103,7 +101,7 @@ public class GitRepositoryResolver implements RepositoryResolver<HttpServletRequ
 
         logger.debug("try to open git repository at {}", gitdir);
 
-        return RepositoryCache.open(FileKey.lenient(gitdir, FS.DETECTED), true);
+        return GitUtil.open(gitdir);
       }
       else
       {