1 files changed, 17 insertions, 7 deletions

diff --git a/src/org/gnunet/construct/parsers/StringParser.java b/src/org/gnunet/construct/parsers/StringParser.java
index a96d396..8df171e 100644
--- a/src/org/gnunet/construct/parsers/StringParser.java
+++ b/src/org/gnunet/construct/parsers/StringParser.java
@@ -21,7 +21,7 @@
 package org.gnunet.construct.parsers;
 
 import org.gnunet.construct.Message;
-import org.gnunet.construct.ProtocolViolation;
+import org.gnunet.construct.ProtocolViolationException;
 import org.gnunet.construct.ReflectUtil;
 
 import java.io.UnsupportedEncodingException;
@@ -63,12 +63,20 @@ public class StringParser implements Parser {
     public int parse(final ByteBuffer srcBuf, int frameOffset, Message frameObj, final Message dstObj, List<Field>
             frameSizePath) {
 
-        if (srcBuf.get(srcBuf.position()) == 0) {
-            if (!optional) {
-                throw new ProtocolViolation("no data received for non-optional string");
+        if (optional) {
+            if (frameSizePath == null) {
+                throw new AssertionError("optional string with no length field in the message!");
+            }
+            final int frameSize = ReflectUtil.justGetInt(dstObj, frameSizePath);
+            int remaining = frameOffset + frameSize - srcBuf.position();
+
+            if (remaining == 0) {
+                if (!optional) {
+                    throw new ProtocolViolationException("no data received for non-optional string");
+                }
+                ReflectUtil.justSet(dstObj, targetField, null);
+                return 0;
             }
-            ReflectUtil.justSet(dstObj, targetField, null);
-            return 1;
         }
 
         int length = 0;
@@ -125,7 +133,9 @@ public class StringParser implements Parser {
 
     @Override
     public void patch(Message m, int frameSize, List<Field> frameSizePath, Message frameObj) {
-        // nothing to patch
+        if (frameSizePath != null) {
+            ReflectUtil.justSetInt(frameObj, frameSizePath, frameSize);
+        }
     }
 
     @Override