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diff --git a/src/util/DynamicFifoBuffer.hxx b/src/util/DynamicFifoBuffer.hxx
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+/*
+ * Copyright (C) 2003-2013 Max Kellermann <max@duempel.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
+ * FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef FIFO_BUFFER_HPP
+#define FIFO_BUFFER_HPP
+
+#include "ForeignFifoBuffer.hxx"
+
+/**
+ * A first-in-first-out buffer: you can append data at the end, and
+ * read data from the beginning.  This class automatically shifts the
+ * buffer as needed.  It is not thread safe.
+ */
+template<typename T>
+class DynamicFifoBuffer : protected ForeignFifoBuffer<T> {
+public:
+	typedef typename ForeignFifoBuffer<T>::size_type size_type;
+	typedef typename ForeignFifoBuffer<T>::pointer_type pointer_type;
+	typedef typename ForeignFifoBuffer<T>::const_pointer_type const_pointer_type;
+
+	explicit DynamicFifoBuffer(size_type _capacity)
+		:ForeignFifoBuffer<T>(new T[_capacity], _capacity) {}
+	~DynamicFifoBuffer() {
+		delete[] GetBuffer();
+	}
+
+	DynamicFifoBuffer(const DynamicFifoBuffer &) = delete;
+
+	using ForeignFifoBuffer<T>::GetCapacity;
+	using ForeignFifoBuffer<T>::Clear;
+	using ForeignFifoBuffer<T>::IsEmpty;
+	using ForeignFifoBuffer<T>::IsFull;
+	using ForeignFifoBuffer<T>::GetAvailable;
+	using ForeignFifoBuffer<T>::Read;
+	using ForeignFifoBuffer<T>::Consume;
+	using ForeignFifoBuffer<T>::Write;
+	using ForeignFifoBuffer<T>::Append;
+
+	void Grow(size_type new_capacity) {
+		assert(new_capacity > GetCapacity());
+
+		T *old_data = GetBuffer();
+		T *new_data = new T[new_capacity];
+		ForeignFifoBuffer<T>::MoveBuffer(new_data, new_capacity);
+		delete[] old_data;
+	}
+
+	void WantWrite(size_type n) {
+		if (ForeignFifoBuffer<T>::WantWrite(n))
+			/* we already have enough space */
+			return;
+
+		const size_type in_use = GetAvailable();
+		const size_type required_capacity = in_use + n;
+		size_type new_capacity = GetCapacity();
+		do {
+			new_capacity <<= 1;
+		} while (new_capacity < required_capacity);
+
+		Grow(new_capacity);
+	}
+
+	/**
+	 * Write data to the buffer, growing it as needed.  Returns a
+	 * writable pointer.
+	 */
+	pointer_type Write(size_type n) {
+		WantWrite(n);
+		return Write().data;
+	}
+
+	/**
+	 * Append data to the buffer, growing it as needed.
+	 */
+	void Append(const_pointer_type p, size_type n) {
+		std::copy_n(p, n, Write(n));
+		Append(n);
+	}
+
+protected:
+	using ForeignFifoBuffer<T>::GetBuffer;
+};
+
+#endif