From d4da92d300e4f7e6b45afa56eb6a1487e679256e Mon Sep 17 00:00:00 2001
From: Joel Dice <joel.dice@gmail.com>
Date: Mon, 16 May 2011 17:12:41 -0600
Subject: [PATCH] fix bugs in Deflater and DeflaterOutputStream

Previously, Deflater.deflate would pass Z_SYNC_FLUSH to zlib
unconditionally, which caused the output to be enormous when setInput
was called repeatedly with very small input buffers.  In order to
allow zlib to buffer output and thereby maximize compression, we must
use Z_NO_FLUSH until Deflater.finish is called, at which point we
switch to Z_FINISH.  We also modify DeflaterOutputStream.close to call
Deflater.finish and write any remaining output to the wrapped stream.
---
 classpath/java-util-zip.cpp                   |  4 +--
 classpath/java/util/zip/Deflater.java         | 27 ++++++++++++------
 .../java/util/zip/DeflaterOutputStream.java   | 28 ++++++++++---------
 3 files changed, 35 insertions(+), 24 deletions(-)

diff --git a/classpath/java-util-zip.cpp b/classpath/java-util-zip.cpp
index a7d969839a..f883e528bc 100644
--- a/classpath/java-util-zip.cpp
+++ b/classpath/java-util-zip.cpp
@@ -121,7 +121,7 @@ Java_java_util_zip_Deflater_deflate
 (JNIEnv* e, jclass, jlong peer, 
  jbyteArray input, jint inputOffset, jint inputLength,
  jbyteArray output, jint outputOffset, jint outputLength,
- jintArray results)
+ jboolean finish, jintArray results)
 {
   z_stream* s = reinterpret_cast<z_stream*>(peer);
 
@@ -145,7 +145,7 @@ Java_java_util_zip_Deflater_deflate
   s->next_out = reinterpret_cast<Bytef*>(out);
   s->avail_out = outputLength;
 
-  int r = deflate(s, Z_SYNC_FLUSH);
+  int r = deflate(s, finish ? Z_FINISH : Z_NO_FLUSH);
   jint resultArray[3]
     = { r, inputLength - s->avail_in, outputLength - s->avail_out };
 
diff --git a/classpath/java/util/zip/Deflater.java b/classpath/java/util/zip/Deflater.java
index d7bfc83b88..28df9754d2 100644
--- a/classpath/java/util/zip/Deflater.java
+++ b/classpath/java/util/zip/Deflater.java
@@ -27,14 +27,19 @@ public class Deflater {
   private boolean needDictionary;
   private boolean finished;
   private final boolean nowrap;
+  private boolean finish;
 
-  public Deflater(boolean nowrap) {
+  public Deflater(int level, boolean nowrap) {
     this.nowrap = nowrap;
-    peer = make(nowrap, DEFAULT_LEVEL);
+    peer = make(nowrap, level);
+  }
+
+  public Deflater(int level) {
+    this(level, false);
   }
 
   public Deflater() {
-    this(false);
+    this(DEFAULT_LEVEL);
   }
 
   private void check() {
@@ -85,16 +90,15 @@ public class Deflater {
     peer = make(nowrap, DEFAULT_LEVEL);
     input = null;
     offset = length = 0;
+    finish = false;
     needDictionary = finished = false;
   }
 
-  public int deflate(byte[] output) throws DataFormatException {
+  public int deflate(byte[] output) {
     return deflate(output, 0, output.length);
   }
 
-  public int deflate(byte[] output, int offset, int length)
-    throws DataFormatException
-  {
+  public int deflate(byte[] output, int offset, int length) {
     final int zlibResult = 0;
     final int inputCount = 1;
     final int outputCount = 2;
@@ -110,10 +114,10 @@ public class Deflater {
     int[] results = new int[3];
     deflate(peer, 
             input, this.offset, this.length,
-            output, offset, length, results);
+            output, offset, length, finish, results);
 
     if (results[zlibResult] < 0) {
-      throw new DataFormatException();
+      throw new AssertionError();
     }
 
     switch (results[zlibResult]) {
@@ -132,10 +136,15 @@ public class Deflater {
     return results[outputCount];
   }
 
+  public void finish() {
+    finish = true;
+  }
+
   private static native void deflate
     (long peer,
      byte[] input, int inputOffset, int inputLength,
      byte[] output, int outputOffset, int outputLength,
+     boolean finish,
      int[] results);
 
   public void dispose() {
diff --git a/classpath/java/util/zip/DeflaterOutputStream.java b/classpath/java/util/zip/DeflaterOutputStream.java
index e55668e53c..3ee3fcdbb8 100644
--- a/classpath/java/util/zip/DeflaterOutputStream.java
+++ b/classpath/java/util/zip/DeflaterOutputStream.java
@@ -52,23 +52,25 @@ public class DeflaterOutputStream extends OutputStream {
     } else if (length == 0) {
       return;
     }
-    
-    for (int i = 0; i < length; i+= buffer.length) {
-      deflater.setInput(b, offset + i, Math.min(buffer.length, length - i));
-      while (deflater.getRemaining() > 0) {
-        try {
-          int len = deflater.deflate(buffer, 0, buffer.length);
-          if (len > 0) {
-            out.write(buffer, 0, len);
-          }
-        } catch (DataFormatException e) {
-          e.printStackTrace();
-        }
-      }
+
+    deflater.setInput(b, offset, length);
+    while (deflater.getRemaining() > 0) {
+      deflate();
+    }
+  }
+
+  private void deflate() throws IOException {
+    int len = deflater.deflate(buffer, 0, buffer.length);
+    if (len > 0) {
+      out.write(buffer, 0, len);
     }
   }
 
   public void close() throws IOException {
+    deflater.finish();
+    while (! deflater.finished()) {
+      deflate();
+    }
     out.close();
     deflater.dispose();
   }