HADOOP-7258. The Gzip codec should not return null decompressors. (omalley)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.20-security-203@1099191 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -74,6 +74,8 @@ Release 0.20.203.0 - unreleased
 
     HADOOP-7232. Fix Javadoc warnings. (omalley)
 
+    HADOOP-7258. The Gzip codec should not return null decompressors. (omalley)
+
 Release 0.20.202.0 - unreleased
 
     MAPREDUCE-2355. Add a configuration knob 

src/core/org/apache/hadoop/io/compress/CodecPool.java

@@ -141,6 +141,10 @@ public class CodecPool {
     if (compressor == null) {
       return;
     }
+    // if the compressor can't be reused, don't pool it.
+    if (compressor.getClass().isAnnotationPresent(DoNotPool.class)) {
+      return;
+    }
     compressor.reset();
     payback(compressorPool, compressor);
   }
@@ -155,6 +159,10 @@ public class CodecPool {
     if (decompressor == null) {
       return;
     }
+    // if the decompressor can't be reused, don't pool it.
+    if (decompressor.getClass().isAnnotationPresent(DoNotPool.class)) {
+      return;
+    }
     decompressor.reset();
     payback(decompressorPool, decompressor);
   }

src/core/org/apache/hadoop/io/compress/DoNotPool.java

@@ -0,0 +1,32 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.io.compress;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+/**
+ * This is a marker annotation that marks a compressor or decompressor 
+ * type as not to be pooled.
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Documented
+public @interface DoNotPool {
+
+}

src/core/org/apache/hadoop/io/compress/GzipCodec.java

@@ -141,7 +141,7 @@ public class GzipCodec extends DefaultCodec {
   public Class<? extends Decompressor> getDecompressorType() {
     return ZlibFactory.isNativeZlibLoaded(conf)
       ? GzipZlibDecompressor.class
-      : null;
+      : BuiltInGzipDecompressor.class;
   }
 
   public String getDefaultExtension() {

src/core/org/apache/hadoop/io/compress/zlib/BuiltInGzipDecompressor.java

@@ -24,6 +24,7 @@ import java.util.zip.Inflater;
 import java.util.zip.CRC32;
 
 import org.apache.hadoop.io.compress.Decompressor;
+import org.apache.hadoop.io.compress.DoNotPool;
 
 /**
  * A {@link Decompressor} based on the popular gzip compressed file format.
@@ -108,6 +109,7 @@ public class BuiltInGzipDecompressor implements Decompressor {
   /**
    * Creates a new (pure Java) gzip decompressor.
    */
+  @DoNotPool
   public BuiltInGzipDecompressor() {
     state = GzipStateLabel.HEADER_BASIC;
     crc.reset();

src/test/org/apache/hadoop/io/compress/TestCodec.java

@@ -480,27 +480,26 @@ public class TestCodec extends TestCase {
     // java.util.zip.GZIPOutputStream.
     CompressionCodecFactory ccf = new CompressionCodecFactory(conf);
     CompressionCodec codec = ccf.getCodec(new Path("foo.gz"));
-    assertTrue("Codec for .gz file is not GzipCodec", codec instanceof GzipCodec);
+    assertTrue("Codec for .gz file is not GzipCodec", 
+               codec instanceof GzipCodec);
     Decompressor codecDecompressor = codec.createDecompressor();
-    if (null != codecDecompressor) {
-      fail("Got non-null codecDecompressor: " + codecDecompressor);
+    if (null == codecDecompressor) {
+      fail("Got null codecDecompressor");
     }
 
     // Asking the CodecPool for a decompressor for GzipCodec
     // should return null as well.
     Decompressor poolDecompressor = CodecPool.getDecompressor(codec);
-    if (null != poolDecompressor) {
-      fail("Got non-null poolDecompressor: " + poolDecompressor);
+    if (null == poolDecompressor) {
+      fail("Got null poolDecompressor: " + poolDecompressor);
     }
-
     // If we then ensure that the pool is populated...
     CodecPool.returnDecompressor(zlibDecompressor);
-
-    // Asking the pool another time should still not bind this to GzipCodec.
-    poolDecompressor = CodecPool.getDecompressor(codec);
-    if (null != poolDecompressor) {
-      fail("Second time, got non-null poolDecompressor: "
-          + poolDecompressor);
+    // return the decompressor
+    CodecPool.returnDecompressor(poolDecompressor);
+    Decompressor poolDecompressor2 = CodecPool.getDecompressor(codec);
+    if (poolDecompressor == poolDecompressor2) {
+      fail("Reused gzip decompressor in pool");
     }
   }