Fix Reference Count Leak (#488)

Previously, there were a couple of frames that converted Strings to ByteBufs
automatically as part of construction.  Those frames though, retained any
ByteBufs passed into them so that they could be released by the creators as
necessary.  Since the automatic construction was not doing this release on the
String-based ByteBufs, there was a minor leak of references.  This change
updates those locations to release the String-based ByteBufs and accurately
account for their retention and release.

Author: nebhale

rsocket-core/src/main/java/io/rsocket/fragmentation/FrameFragmenter.java

@@ -17,7 +17,7 @@
 package io.rsocket.fragmentation;
 
 import static io.rsocket.framing.PayloadFrame.createPayloadFrame;
-import static io.rsocket.util.DisposableUtil.disposeQuietly;
+import static io.rsocket.util.DisposableUtils.disposeQuietly;
 import static java.lang.Math.min;
 
 import io.netty.buffer.ByteBuf;

rsocket-core/src/main/java/io/rsocket/fragmentation/FrameReassembler.java

@@ -16,7 +16,7 @@
 
 package io.rsocket.fragmentation;
 
-import static io.rsocket.util.DisposableUtil.disposeQuietly;
+import static io.rsocket.util.DisposableUtils.disposeQuietly;
 import static io.rsocket.util.RecyclerFactory.createRecycler;
 
 import io.netty.buffer.ByteBuf;

rsocket-core/src/main/java/io/rsocket/framing/AbstractRecyclableFrame.java

@@ -16,12 +16,14 @@
 
 package io.rsocket.framing;
 
+import static io.netty.util.ReferenceCountUtil.release;
 import static java.nio.charset.StandardCharsets.UTF_8;
 
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufAllocator;
 import io.netty.buffer.Unpooled;
 import io.netty.util.Recycler.Handle;
+import io.netty.util.ReferenceCounted;
 import java.util.Objects;
 import reactor.util.annotation.Nullable;
 
@@ -51,7 +53,7 @@ abstract class AbstractRecyclableFrame<SELF extends AbstractRecyclableFrame<SELF
   @SuppressWarnings("unchecked")
   public final void dispose() {
     if (byteBuf != null) {
-      byteBuf.release();
+      release(byteBuf);
     }
 
     byteBuf = null;

rsocket-core/src/main/java/io/rsocket/framing/DataFrame.java

@@ -51,6 +51,7 @@ default int getDataLength() {
    * it.
    *
    * @return the data directly
+   * @see #getDataAsUtf8()
    * @see #mapData(Function)
    */
   ByteBuf getUnsafeData();

rsocket-core/src/main/java/io/rsocket/framing/ErrorFrame.java

@@ -16,6 +16,7 @@
 
 package io.rsocket.framing;
 
+import static io.netty.util.ReferenceCountUtil.release;
 import static io.rsocket.framing.FrameType.ERROR;
 import static io.rsocket.util.RecyclerFactory.createRecycler;
 
@@ -70,7 +71,13 @@ public static ErrorFrame createErrorFrame(ByteBuf byteBuf) {
   public static ErrorFrame createErrorFrame(
       ByteBufAllocator byteBufAllocator, int errorCode, @Nullable String data) {
 
-    return createErrorFrame(byteBufAllocator, errorCode, getUtf8AsByteBuf(data));
+    ByteBuf dataByteBuf = getUtf8AsByteBuf(data);
+
+    try {
+      return createErrorFrame(byteBufAllocator, errorCode, dataByteBuf);
+    } finally {
+      release(dataByteBuf);
+    }
   }
 
   /**

rsocket-core/src/main/java/io/rsocket/framing/ExtensionFrame.java

@@ -16,6 +16,7 @@
 
 package io.rsocket.framing;
 
+import static io.netty.util.ReferenceCountUtil.release;
 import static io.rsocket.framing.FrameType.EXT;
 import static io.rsocket.util.RecyclerFactory.createRecycler;
 
@@ -79,8 +80,16 @@ public static ExtensionFrame createExtensionFrame(
       @Nullable String metadata,
       @Nullable String data) {
 
-    return createExtensionFrame(
-        byteBufAllocator, ignore, extendedType, getUtf8AsByteBuf(metadata), getUtf8AsByteBuf(data));
+    ByteBuf metadataByteBuf = getUtf8AsByteBuf(metadata);
+    ByteBuf dataByteBuf = getUtf8AsByteBuf(data);
+
+    try {
+      return createExtensionFrame(
+          byteBufAllocator, ignore, extendedType, metadataByteBuf, dataByteBuf);
+    } finally {
+      release(metadataByteBuf);
+      release(dataByteBuf);
+    }
   }
 
   /**

rsocket-core/src/main/java/io/rsocket/framing/MetadataFrame.java

@@ -55,6 +55,7 @@ default Optional<Integer> getMetadataLength() {
    * if you store it.
    *
    * @return the metadata directly, or {@code null} if the Metadata flag is not set
+   * @see #getMetadataAsUtf8()
    * @see #mapMetadata(Function)
    */
   @Nullable

rsocket-core/src/main/java/io/rsocket/framing/MetadataPushFrame.java

@@ -16,6 +16,7 @@
 
 package io.rsocket.framing;
 
+import static io.netty.util.ReferenceCountUtil.release;
 import static io.rsocket.framing.FrameType.METADATA_PUSH;
 import static io.rsocket.util.RecyclerFactory.createRecycler;
 
@@ -69,8 +70,13 @@ public static MetadataPushFrame createMetadataPushFrame(ByteBuf byteBuf) {
   public static MetadataPushFrame createMetadataPushFrame(
       ByteBufAllocator byteBufAllocator, String metadata) {
 
-    return createMetadataPushFrame(
-        byteBufAllocator, getUtf8AsByteBufRequired(metadata, "metadata must not be null"));
+    ByteBuf metadataByteBuf = getUtf8AsByteBufRequired(metadata, "metadata must not be null");
+
+    try {
+      return createMetadataPushFrame(byteBufAllocator, metadataByteBuf);
+    } finally {
+      release(metadataByteBuf);
+    }
   }
 
   /**

rsocket-core/src/main/java/io/rsocket/framing/PayloadFrame.java

@@ -16,6 +16,7 @@
 
 package io.rsocket.framing;
 
+import static io.netty.util.ReferenceCountUtil.release;
 import static io.rsocket.util.RecyclerFactory.createRecycler;
 
 import io.netty.buffer.ByteBuf;
@@ -78,8 +79,15 @@ public static PayloadFrame createPayloadFrame(
       @Nullable String metadata,
       @Nullable String data) {
 
-    return createPayloadFrame(
-        byteBufAllocator, follows, complete, getUtf8AsByteBuf(metadata), getUtf8AsByteBuf(data));
+    ByteBuf metadataByteBuf = getUtf8AsByteBuf(metadata);
+    ByteBuf dataByteBuf = getUtf8AsByteBuf(data);
+
+    try {
+      return createPayloadFrame(byteBufAllocator, follows, complete, metadataByteBuf, dataByteBuf);
+    } finally {
+      release(metadataByteBuf);
+      release(dataByteBuf);
+    }
   }
 
   /**

rsocket-core/src/main/java/io/rsocket/framing/RequestChannelFrame.java

@@ -16,6 +16,7 @@
 
 package io.rsocket.framing;
 
+import static io.netty.util.ReferenceCountUtil.release;
 import static io.rsocket.util.RecyclerFactory.createRecycler;
 
 import io.netty.buffer.ByteBuf;
@@ -83,13 +84,16 @@ public static RequestChannelFrame createRequestChannelFrame(
       @Nullable String metadata,
       @Nullable String data) {
 
-    return createRequestChannelFrame(
-        byteBufAllocator,
-        follows,
-        complete,
-        initialRequestN,
-        getUtf8AsByteBuf(metadata),
-        getUtf8AsByteBuf(data));
+    ByteBuf metadataByteBuf = getUtf8AsByteBuf(metadata);
+    ByteBuf dataByteBuf = getUtf8AsByteBuf(data);
+
+    try {
+      return createRequestChannelFrame(
+          byteBufAllocator, follows, complete, initialRequestN, metadataByteBuf, dataByteBuf);
+    } finally {
+      release(metadataByteBuf);
+      release(dataByteBuf);
+    }
   }
 
   /**