ndnboost: Include boost::iostreams for internal use.
diff --git a/include/ndnboost/iostreams/filter/counter.hpp b/include/ndnboost/iostreams/filter/counter.hpp
new file mode 100644
index 0000000..4780c16
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+++ b/include/ndnboost/iostreams/filter/counter.hpp
@@ -0,0 +1,82 @@
+// (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
+// (C) Copyright 2005-2007 Jonathan Turkanis
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)
+
+// See http://www.boost.org/libs/iostreams for documentation.
+
+#ifndef NDNBOOST_IOSTREAMS_COUNTER_HPP_INCLUDED
+#define NDNBOOST_IOSTREAMS_COUNTER_HPP_INCLUDED
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+#include <algorithm>  // count.
+#include <ndnboost/iostreams/categories.hpp>
+#include <ndnboost/iostreams/char_traits.hpp>
+#include <ndnboost/iostreams/operations.hpp>
+#include <ndnboost/iostreams/pipeline.hpp>
+
+// Must come last.
+#include <ndnboost/iostreams/detail/config/disable_warnings.hpp> // VC7.1 C4244.
+
+namespace ndnboost { namespace iostreams {
+
+//
+// Template name: basic_counter.
+// Template parameters:
+//      Ch - The character type.
+// Description: Filter which counts lines and characters.
+//
+template<typename Ch>
+class basic_counter  {
+public:
+    typedef Ch char_type;
+    struct category
+        : dual_use,
+          filter_tag,
+          multichar_tag,
+          optimally_buffered_tag
+        { };
+    explicit basic_counter(int first_line = 0, int first_char = 0)
+        : lines_(first_line), chars_(first_char)
+        { }
+    int lines() const { return lines_; }
+    int characters() const { return chars_; }
+    std::streamsize optimal_buffer_size() const { return 0; }
+
+    template<typename Source>
+    std::streamsize read(Source& src, char_type* s, std::streamsize n)
+    {
+        std::streamsize result = iostreams::read(src, s, n);
+        if (result == -1)
+            return -1;
+        lines_ += std::count(s, s + result, char_traits<Ch>::newline());
+        chars_ += result;
+        return result;
+    }
+
+    template<typename Sink>
+    std::streamsize write(Sink& snk, const char_type* s, std::streamsize n)
+    {
+        std::streamsize result = iostreams::write(snk, s, n);
+        lines_ += std::count(s, s + result, char_traits<Ch>::newline());
+        chars_ += result;
+        return result;
+    }
+private:
+    int lines_;
+    int chars_;
+};
+NDNBOOST_IOSTREAMS_PIPABLE(basic_counter, 1)
+
+
+typedef basic_counter<char>     counter;
+typedef basic_counter<wchar_t>  wcounter;
+
+} } // End namespaces iostreams, boost.
+
+#include <ndnboost/iostreams/detail/config/enable_warnings.hpp>
+
+#endif // #ifndef NDNBOOST_IOSTREAMS_COUNTER_HPP_INCLUDED