#11736 do not rethrow already thrown exception

Signed-off-by: Ludovic Orban <lorban@bitronix.be>

jetty-core/jetty-io/src/main/java/org/eclipse/jetty/io/content/ContentSinkOutputStream.java

@@ -33,6 +33,7 @@ public class ContentSinkOutputStream extends OutputStream
 {
     private final Blocker.Shared _blocking = new Blocker.Shared();
     private final Content.Sink sink;
+    private boolean failed;
 
     public ContentSinkOutputStream(Content.Sink sink)
     {
@@ -55,7 +56,7 @@ public void write(byte[] b, int off, int len) throws IOException
         }
         catch (Throwable x)
         {
-            throw IO.rethrow(x);
+            handleException(x);
         }
     }
 
@@ -69,7 +70,7 @@ public void flush() throws IOException
         }
         catch (Throwable x)
         {
-            throw IO.rethrow(x);
+            handleException(x);
         }
     }
 
@@ -83,12 +84,20 @@ public void close() throws IOException
         }
         catch (Throwable x)
         {
-            throw IO.rethrow(x);
+            handleException(x);
         }
     }
 
     public void close(Callback callback) throws IOException
     {
         sink.write(true, null, callback);
     }
+
+    private void handleException(Throwable x) throws IOException
+    {
+        if (failed)
+            throw new IOException(x.toString());
+        failed = true;
+        throw IO.rethrow(x);
+    }
 }

jetty-core/jetty-io/src/test/java/org/eclipse/jetty/io/content/ContentSinkOutputStreamTest.java

@@ -0,0 +1,58 @@
+//
+// ========================================================================
+// Copyright (c) 1995 Mort Bay Consulting Pty Ltd and others.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// https://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
+// which is available at https://www.apache.org/licenses/LICENSE-2.0.
+//
+// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
+// ========================================================================
+//
+
+package org.eclipse.jetty.io.content;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.PrintWriter;
+import java.io.StringWriter;
+
+import org.eclipse.jetty.io.Content;
+import org.eclipse.jetty.io.EofException;
+import org.junit.jupiter.api.Test;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.not;
+import static org.junit.jupiter.api.Assertions.fail;
+
+public class ContentSinkOutputStreamTest
+{
+    @Test
+    public void testNoDuplicateExceptionThrown()
+    {
+        EofException eofException = new EofException();
+        Content.Sink sink = (last, byteBuffer, callback) -> callback.failed(eofException);
+
+        StringWriter stringWriter = new StringWriter();
+        try (OutputStream body = new ContentSinkOutputStream(sink))
+        {
+            try
+            {
+                body.write('a');
+                fail("expected IOException in write()");
+            }
+            catch (IOException e)
+            {
+                body.flush();
+                fail("expected IOException in flush()");
+            }
+        }
+        catch (IOException ex)
+        {
+            ex.printStackTrace(new PrintWriter(stringWriter));
+        }
+        assertThat(stringWriter.toString(), not(containsString("CIRCULAR REFERENCE")));
+    }
+}