From 3272f8902bbf1a5001606c48f333a60b324bf288 Mon Sep 17 00:00:00 2001
From: David Renshaw <dwrenshaw@gmail.com>
Date: Fri, 5 Sep 2014 11:43:46 -0400
Subject: [PATCH] fix ByteChannelMessageReader for multi-segment messages

---
 .../org/capnproto/ByteChannelMessageReader.java    | 14 ++++++--------
 .../src/main/java/org/capnproto/SegmentReader.java |  2 --
 .../src/main/java/org/capnproto/WireHelpers.java   |  3 +--
 3 files changed, 7 insertions(+), 12 deletions(-)

diff --git a/runtime/src/main/java/org/capnproto/ByteChannelMessageReader.java b/runtime/src/main/java/org/capnproto/ByteChannelMessageReader.java
index 0ca0fa3..10eb9c3 100644
--- a/runtime/src/main/java/org/capnproto/ByteChannelMessageReader.java
+++ b/runtime/src/main/java/org/capnproto/ByteChannelMessageReader.java
@@ -62,20 +62,18 @@ public final class ByteChannelMessageReader {
 
         ByteBuffer[] segmentSlices = new ByteBuffer[segmentCount];
 
-        segmentSlices[0] = ByteBuffer.wrap(allSegments.array(),
-                                           0,
-                                           segment0Size * Constants.BYTES_PER_WORD);
+        allSegments.rewind();
+        segmentSlices[0] = allSegments.slice();
+        segmentSlices[0].limit(segment0Size * Constants.BYTES_PER_WORD);
         segmentSlices[0].order(ByteOrder.LITTLE_ENDIAN);
-        segmentSlices[0].mark();
 
         int offset = segment0Size;
 
         for (int ii = 1; ii < segmentCount; ++ii) {
-            segmentSlices[ii] = ByteBuffer.wrap(allSegments.array(),
-                                                offset * Constants.BYTES_PER_WORD,
-                                                moreSizes.get(ii - 1) * Constants.BYTES_PER_WORD);
+            allSegments.position(offset * Constants.BYTES_PER_WORD);
+            segmentSlices[ii] = allSegments.slice();
+            segmentSlices[ii].limit(moreSizes.get(ii - 1) * Constants.BYTES_PER_WORD);
             segmentSlices[ii].order(ByteOrder.LITTLE_ENDIAN);
-            segmentSlices[ii].mark();
             offset += moreSizes.get(ii - 1);
         }
 
diff --git a/runtime/src/main/java/org/capnproto/SegmentReader.java b/runtime/src/main/java/org/capnproto/SegmentReader.java
index 0ffb294..756362d 100644
--- a/runtime/src/main/java/org/capnproto/SegmentReader.java
+++ b/runtime/src/main/java/org/capnproto/SegmentReader.java
@@ -4,9 +4,7 @@ import java.nio.ByteBuffer;
 
 public class SegmentReader {
 
-    // invariant: buffer's mark is at its beginning.
     final ByteBuffer buffer;
-
     final Arena arena;
 
     public SegmentReader(ByteBuffer buffer, Arena arena) {
diff --git a/runtime/src/main/java/org/capnproto/WireHelpers.java b/runtime/src/main/java/org/capnproto/WireHelpers.java
index 75bc9d8..27da268 100644
--- a/runtime/src/main/java/org/capnproto/WireHelpers.java
+++ b/runtime/src/main/java/org/capnproto/WireHelpers.java
@@ -337,7 +337,6 @@ final class WireHelpers {
                                                  int nestingLimit) {
 
         // TODO error handling. is_null
-
         if (nestingLimit <= 0) {
             throw new DecodeException("Message is too deeply nested or contains cycles.");
         }
@@ -369,6 +368,7 @@ final class WireHelpers {
                                              int refOffset,
                                              byte expectedElementSize,
                                              int nestingLimit) {
+
         long ref = WirePointer.get(segment.buffer, refOffset);
 
         if (WirePointer.isNull(ref)) {
@@ -413,7 +413,6 @@ final class WireHelpers {
             //# lists can also be interpreted as struct lists. We
             //# need to compute the data size and pointer count for
             //# such structs.
-
             int dataSize = FieldSize.dataBitsPerElement(ListPointer.elementSize(resolved.ref));
             int pointerCount = FieldSize.pointersPerElement(ListPointer.elementSize(resolved.ref));
             int step = dataSize + pointerCount * Constants.BITS_PER_POINTER;