From 7a04b3eb19820c66b65d026cfd972a49689dc582 Mon Sep 17 00:00:00 2001
From: Lachlan Roberts <lachlan@webtide.com>
Date: Tue, 8 Sep 2020 17:10:36 +1000
Subject: [PATCH] Issue #5198 - use ByteBuffer API for inflater/deflaters for
 GzipHandler

Signed-off-by: Lachlan Roberts <lachlan@webtide.com>
---
 .../jetty/http/GZIPContentDecoder.java        | 19 ++---------
 .../gzip/GzipHttpOutputInterceptor.java       | 34 +++----------------
 2 files changed, 7 insertions(+), 46 deletions(-)

diff --git a/jetty-http/src/main/java/org/eclipse/jetty/http/GZIPContentDecoder.java b/jetty-http/src/main/java/org/eclipse/jetty/http/GZIPContentDecoder.java
index 8a2cd758c86..dc30bfd2899 100644
--- a/jetty-http/src/main/java/org/eclipse/jetty/http/GZIPContentDecoder.java
+++ b/jetty-http/src/main/java/org/eclipse/jetty/http/GZIPContentDecoder.java
@@ -216,8 +216,7 @@ public class GZIPContentDecoder implements Destroyable
 
                             try
                             {
-                                int length = _inflater.inflate(buffer.array(), buffer.arrayOffset(), buffer.capacity());
-                                buffer.limit(length);
+                                _inflater.inflate(buffer);
                             }
                             catch (DataFormatException x)
                             {
@@ -235,23 +234,10 @@ public class GZIPContentDecoder implements Destroyable
                             {
                                 if (!compressed.hasRemaining())
                                     return;
-                                if (compressed.hasArray())
-                                {
-                                    _inflater.setInput(compressed.array(), compressed.arrayOffset() + compressed.position(), compressed.remaining());
-                                    compressed.position(compressed.limit());
-                                }
-                                else
-                                {
-                                    // TODO use the pool
-                                    byte[] input = new byte[compressed.remaining()];
-                                    compressed.get(input);
-                                    _inflater.setInput(input);
-                                }
+                                _inflater.setInput(compressed);
                             }
                             else if (_inflater.finished())
                             {
-                                int remaining = _inflater.getRemaining();
-                                compressed.position(compressed.limit() - remaining);
                                 _state = State.CRC;
                                 _size = 0;
                                 _value = 0;
@@ -395,7 +381,6 @@ public class GZIPContentDecoder implements Destroyable
                             if (_value != (_inflater.getBytesWritten() & UINT_MAX))
                                 throw new ZipException("Invalid input size");
 
-                            // TODO ByteBuffer result = output == null ? BufferUtil.EMPTY_BUFFER : ByteBuffer.wrap(output);
                             reset();
                             return;
                         }
diff --git a/jetty-server/src/main/java/org/eclipse/jetty/server/handler/gzip/GzipHttpOutputInterceptor.java b/jetty-server/src/main/java/org/eclipse/jetty/server/handler/gzip/GzipHttpOutputInterceptor.java
index 7a39f160b95..48271d6f6bb 100644
--- a/jetty-server/src/main/java/org/eclipse/jetty/server/handler/gzip/GzipHttpOutputInterceptor.java
+++ b/jetty-server/src/main/java/org/eclipse/jetty/server/handler/gzip/GzipHttpOutputInterceptor.java
@@ -196,7 +196,6 @@ public class GzipHttpOutputInterceptor implements HttpOutput.Interceptor
                 contentLength = content.remaining();
 
             _deflater = _factory.getDeflater(_channel.getRequest(), contentLength);
-
             if (_deflater == null)
             {
                 LOG.debug("{} exclude no deflater", this);
@@ -334,39 +333,16 @@ public class GzipHttpOutputInterceptor implements HttpOutput.Interceptor
                     }
                     else
                     {
-                        // If there is more content available to compress, we have to make sure
-                        // it is available in an array for the current deflator API, maybe slicing
-                        // of content.
-                        ByteBuffer slice;
-                        if (_content.hasArray())
-                            slice = _content;
-                        else
-                        {
-                            if (_copy == null)
-                                _copy = _channel.getByteBufferPool().acquire(_bufferSize, false);
-                            else
-                                BufferUtil.clear(_copy);
-                            slice = _copy;
-                            BufferUtil.append(_copy, _content);
-                        }
-
-                        // transfer the data from the slice to the the deflator
-                        byte[] array = slice.array();
-                        int off = slice.arrayOffset() + slice.position();
-                        int len = slice.remaining();
-                        _crc.update(array, off, len);
-                        _deflater.setInput(array, off, len);  // TODO use ByteBuffer API in Jetty-10
-                        slice.position(slice.position() + len);
-                        if (_last && BufferUtil.isEmpty(_content))
+                        // TODO: this might be a bad place to use ByteBuffer API, the CRC can copy the buffer anyway.
+                        _crc.update(_content.slice());
+                        _deflater.setInput(_content.slice());
+                        if (_last)
                             _deflater.finish();
                     }
                 }
 
                 // deflate the content into the available space in the buffer
-                int off = _buffer.arrayOffset() + _buffer.limit();
-                int len = BufferUtil.space(_buffer);
-                int produced = _deflater.deflate(_buffer.array(), off, len, _syncFlush ? Deflater.SYNC_FLUSH : Deflater.NO_FLUSH);
-                _buffer.limit(_buffer.limit() + produced);
+                _deflater.deflate(_buffer, _syncFlush ? Deflater.SYNC_FLUSH : Deflater.NO_FLUSH);
             }
 
             // If we have finished deflation and there is room for the trailer.