HDFS-2132. Potential resource leak in EditLogFileOutputStream.close. (atm)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1145428 13f79535-47bb-0310-9956-ffa450edef68

hdfs/CHANGES.txt

@@ -818,6 +818,8 @@ Trunk (unreleased changes)
     reading only from a currently being written block. (John George via
     szetszwo)
 
+    HDFS-2132. Potential resource leak in EditLogFileOutputStream.close. (atm)
+
 Release 0.22.0 - Unreleased
 
   INCOMPATIBLE CHANGES

hdfs/src/java/org/apache/hadoop/hdfs/server/namenode/EditLogFileOutputStream.java

@@ -28,8 +28,11 @@ import java.util.zip.Checksum;
 
 import org.apache.hadoop.hdfs.protocol.FSConstants;
 import org.apache.hadoop.io.DataOutputBuffer;
+import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.io.Writable;
 
+import com.google.common.annotations.VisibleForTesting;
+
 /**
  * An implementation of the abstract class {@link EditLogOutputStream}, which
  * stores edits in a local file.
@@ -120,32 +123,41 @@ class EditLogFileOutputStream extends EditLogOutputStream {
 
   @Override
   public void close() throws IOException {
-    // close should have been called after all pending transactions
-    // have been flushed & synced.
-    // if already closed, just skip
-    if(bufCurrent != null)
-    {
-      int bufSize = bufCurrent.size();
-      if (bufSize != 0) {
-        throw new IOException("FSEditStream has " + bufSize
-            + " bytes still to be flushed and cannot " + "be closed.");
+    try {
+      // close should have been called after all pending transactions
+      // have been flushed & synced.
+      // if already closed, just skip
+      if(bufCurrent != null)
+      {
+        int bufSize = bufCurrent.size();
+        if (bufSize != 0) {
+          throw new IOException("FSEditStream has " + bufSize
+              + " bytes still to be flushed and cannot " + "be closed.");
+        }
+        bufCurrent.close();
+        bufCurrent = null;
       }
-      bufCurrent.close();
-      bufCurrent = null;
-    }
-
-    if(bufReady != null) {
-      bufReady.close();
-      bufReady = null;
-    }
-
-    // remove the last INVALID marker from transaction log.
-    if (fc != null && fc.isOpen()) {
-      fc.truncate(fc.position());
-      fc.close();
-    }
-    if (fp != null) {
-      fp.close();
+  
+      if(bufReady != null) {
+        bufReady.close();
+        bufReady = null;
+      }
+  
+      // remove the last INVALID marker from transaction log.
+      if (fc != null && fc.isOpen()) {
+        fc.truncate(fc.position());
+        fc.close();
+        fc = null;
+      }
+      if (fp != null) {
+        fp.close();
+        fp = null;
+      }
+    } finally {
+      IOUtils.cleanup(FSNamesystem.LOG, bufCurrent, bufReady, fc, fp);
+      bufCurrent = bufReady = null;
+      fc = null;
+      fp = null;
     }
   }
 
@@ -225,4 +237,14 @@ class EditLogFileOutputStream extends EditLogOutputStream {
   File getFile() {
     return file;
   }
+  
+  @VisibleForTesting
+  public void setFileChannelForTesting(FileChannel fc) {
+    this.fc = fc;
+  }
+  
+  @VisibleForTesting
+  public FileChannel getFileChannelForTesting() {
+    return fc;
+  }
 }

hdfs/src/test/hdfs/org/apache/hadoop/hdfs/server/namenode/TestEditLogFileOutputStream.java

@@ -20,9 +20,11 @@ package org.apache.hadoop.hdfs.server.namenode;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 import java.io.File;
 import java.io.IOException;
+import java.nio.channels.FileChannel;
 
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.DU;
@@ -31,6 +33,7 @@ import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.hdfs.HdfsConfiguration;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.junit.Test;
+import org.mockito.Mockito;
 
 public class TestEditLogFileOutputStream {
 
@@ -58,5 +61,29 @@ public class TestEditLogFileOutputStream {
     assertTrue("Edit log disk space used should be at least 257 blocks",
         257 * 4096 <= new DU(editLog, conf).getUsed());
   }
+  
+  @Test
+  public void testClose() throws IOException {
+    String errorMessage = "TESTING: fc.truncate() threw IOE";
+    
+    File testDir = new File(System.getProperty("test.build.data", "/tmp"));
+    assertTrue("could not create test directory", testDir.exists() || testDir.mkdirs());
+    File f = new File(testDir, "edits");
+    assertTrue("could not create test file", f.createNewFile());
+    EditLogFileOutputStream elos = new EditLogFileOutputStream(f, 0);
+    
+    FileChannel mockFc = Mockito.spy(elos.getFileChannelForTesting());
+    Mockito.doThrow(new IOException(errorMessage)).when(mockFc).truncate(Mockito.anyLong());
+    elos.setFileChannelForTesting(mockFc);
+    
+    try {
+      elos.close();
+      fail("elos.close() succeeded, but should have thrown");
+    } catch (IOException e) {
+      assertEquals("wrong IOE thrown from elos.close()", e.getMessage(), errorMessage);
+    }
+    
+    assertEquals("fc was not nulled when elos.close() failed", elos.getFileChannelForTesting(), null);
+  }
 
 }