From 734d18fb93da4f363acca96bd78ca6ca0f4b577b Mon Sep 17 00:00:00 2001
From: Joakim Erdfelt <joakim.erdfelt@gmail.com>
Date: Fri, 22 Jan 2016 14:07:51 -0700
Subject: [PATCH] 486394 - MultipartConfig.fileSizeThreshold default of 0
 should always create a file

+ Refactored fileSizeThreshold logic so that a configuration value of
   0 is always create file
   (negative) is never create file
   positive is tested against filesize
---
 .../util/MultiPartInputStreamParser.java      | 30 +++++++++++++++++--
 1 file changed, 28 insertions(+), 2 deletions(-)

diff --git a/jetty-util/src/main/java/org/eclipse/jetty/util/MultiPartInputStreamParser.java b/jetty-util/src/main/java/org/eclipse/jetty/util/MultiPartInputStreamParser.java
index 946d708c307..95fbcd635ef 100644
--- a/jetty-util/src/main/java/org/eclipse/jetty/util/MultiPartInputStreamParser.java
+++ b/jetty-util/src/main/java/org/eclipse/jetty/util/MultiPartInputStreamParser.java
@@ -40,6 +40,7 @@ import java.util.List;
 import java.util.Locale;
 
 import javax.servlet.MultipartConfigElement;
+import javax.servlet.annotation.MultipartConfig;
 import javax.servlet.http.Part;
 
 import org.eclipse.jetty.util.log.Log;
@@ -112,7 +113,7 @@ public class MultiPartInputStreamParser
             if (MultiPartInputStreamParser.this._config.getMaxFileSize() > 0 && _size + 1 > MultiPartInputStreamParser.this._config.getMaxFileSize())
                 throw new IllegalStateException ("Multipart Mime part "+_name+" exceeds max filesize");
 
-            if (MultiPartInputStreamParser.this._config.getFileSizeThreshold() > 0 && _size + 1 > MultiPartInputStreamParser.this._config.getFileSizeThreshold() && _file==null)
+            if (_file == null && MultiPartInputStreamParser.this.isFileNeeded(_size + 1))
                 createFile();
 
             _out.write(b);
@@ -125,7 +126,7 @@ public class MultiPartInputStreamParser
             if (MultiPartInputStreamParser.this._config.getMaxFileSize() > 0 && _size + length > MultiPartInputStreamParser.this._config.getMaxFileSize())
                 throw new IllegalStateException ("Multipart Mime part "+_name+" exceeds max filesize");
 
-            if (MultiPartInputStreamParser.this._config.getFileSizeThreshold() > 0 && _size + length > MultiPartInputStreamParser.this._config.getFileSizeThreshold() && _file==null)
+            if (_file == null && MultiPartInputStreamParser.this.isFileNeeded(_size + length))
                 createFile();
 
             _out.write(bytes, offset, length);
@@ -429,6 +430,31 @@ public class MultiPartInputStreamParser
     }
 
 
+    /**
+     * Test to determine if the file content sizes exceeds the {@link MultipartConfig#fileSizeThreshold()} 
+     * necessary to produce a file on disk
+     * <p>
+     * Configured {@link MultipartConfig#fileSizeThreshold()} of <code>0</code> is always true, negative is always false, 
+     * all other configurations are tested against <code>size</code> parameter
+     *  
+     * @param size the file size to test against.
+     * @return true if file is needed, false otherwise
+     */
+    protected boolean isFileNeeded(long size)
+    {
+        if (_config.getFileSizeThreshold() < 0)
+        {
+            // Negative file size threshold means no file, ever
+            return false;
+        }
+        if (_config.getFileSizeThreshold() == 0)
+        {
+            // 0 means always create a file
+            return true;
+        }
+        return size > _config.getFileSizeThreshold();
+    }
+
     /**
      * Parse, if necessary, the multipart stream.
      *