Bug 654872, QPID-3007: Batch management messages by count, not size.

QMF V1 management messages were being batched by accumulating up to a
certain total size of data. Since management messages may have
different sizes on brokers in a cluster, this was leading to
inconsistencies.

This patch batches V1 messages by count rather than by size, similar
to V2 messages.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk/qpid@1061308 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 60 insertions, 0 deletions

diff --git a/cpp/include/qpid/framing/ResizableBuffer.h b/cpp/include/qpid/framing/ResizableBuffer.h
new file mode 100644
index 0000000000..e6c9e7a113
--- /dev/null
+++ b/cpp/include/qpid/framing/ResizableBuffer.h
@@ -0,0 +1,60 @@
+#ifndef QPID_FRAMING_RESIZABLEBUFFER_H
+#define QPID_FRAMING_RESIZABLEBUFFER_H
+
+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+
+#include "Buffer.h"
+#include <vector>
+
+namespace qpid {
+namespace framing {
+
+/**
+ * A buffer that maintains its own storage and can be resized, 
+ * keeping any data already written to the buffer. 
+ */
+class ResizableBuffer : public Buffer
+{
+  public:
+    ResizableBuffer(size_t initialSize) : store(initialSize) {
+        static_cast<Buffer&>(*this) = Buffer(&store[0], store.size());
+    }
+    
+    void resize(size_t newSize) {
+        size_t oldPos =  getPosition();
+        store.resize(newSize);
+        static_cast<Buffer&>(*this) = Buffer(&store[0], store.size());
+        setPosition(oldPos);
+    }
+
+    /** Make sure at least n bytes are available */
+    void makeAvailable(size_t n) {
+        if (n > available())
+            resize(getSize() + n - available());
+    }
+    
+  private:
+    std::vector<char> store;
+};
+}} // namespace qpid::framing
+
+#endif  /*!QPID_FRAMING_RESIZABLEBUFFER_H*/