comparison DEPENDENCIES/generic/include/boost/iostreams/detail/adapter/range_adapter.hpp @ 16:2665513ce2d3

Add boost headers

+// (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
+// (C) Copyright 2003-2007 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 BOOST_IOSTREAMS_DETAIL_RANGE_ADAPTER_HPP_INCLUDED
+#define BOOST_IOSTREAMS_DETAIL_RANGE_ADAPTER_HPP_INCLUDED
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif              
+
+#include <algorithm>                             // min.
+#include <boost/assert.hpp>
+#include <cstddef>                               // ptrdiff_t.
+#include <iosfwd>                                // streamsize, streamoff.
+#include <boost/detail/iterator.hpp>             // boost::iterator_traits.
+#include <boost/iostreams/categories.hpp>
+#include <boost/iostreams/detail/error.hpp>
+#include <boost/iostreams/positioning.hpp>
+#include <boost/mpl/if.hpp>
+#include <boost/throw_exception.hpp>
+#include <boost/type_traits/is_convertible.hpp>
+#include <boost/utility/enable_if.hpp>
+
+// Must come last.
+#include <boost/iostreams/detail/config/disable_warnings.hpp>  // MSVC.
+
+namespace boost { namespace iostreams { namespace detail {
+
+// Used for simulated tag dispatch.
+template<typename Traversal> struct range_adapter_impl;
+
+//
+// Template name: range_adapter
+// Description: Device based on an instance of boost::iterator_range.
+// Template parameters:
+//     Mode - A mode tag.
+//     Range - An instance of iterator_range.
+//
+template<typename Mode, typename Range>
+class range_adapter {
+private:
+    typedef typename Range::iterator                  iterator;
+    typedef boost::detail::iterator_traits<iterator>  iter_traits;
+    typedef typename iter_traits::iterator_category   iter_cat;
+public:
+    typedef typename Range::value_type                char_type;
+    struct category : Mode, device_tag { };
+    typedef typename
+            mpl::if_<
+                is_convertible<
+                    iter_cat,
+                    std::random_access_iterator_tag
+                >,
+                std::random_access_iterator_tag,
+                std::forward_iterator_tag
+            >::type                                   tag;
+    typedef range_adapter_impl<tag>                   impl;
+
+    explicit range_adapter(const Range& rng);
+    range_adapter(iterator first, iterator last);
+    std::streamsize read(char_type* s, std::streamsize n);
+    std::streamsize write(const char_type* s, std::streamsize n);
+    std::streampos seek(stream_offset off, BOOST_IOS::seekdir way);
+private:
+    iterator first_, cur_, last_;
+};
+
+//------------------Implementation of range_adapter---------------------------//
+
+template<typename Mode, typename Range>
+range_adapter<Mode, Range>::range_adapter(const Range& rng)
+    : first_(rng.begin()), cur_(rng.begin()), last_(rng.end()) { }
+
+template<typename Mode, typename Range>
+range_adapter<Mode, Range>::range_adapter(iterator first, iterator last)
+    : first_(first), cur_(first), last_(last) { }
+
+template<typename Mode, typename Range>
+inline std::streamsize range_adapter<Mode, Range>::read
+    (char_type* s, std::streamsize n)
+{ return impl::read(cur_, last_, s, n); }
+
+template<typename Mode, typename Range>
+inline std::streamsize range_adapter<Mode, Range>::write
+    (const char_type* s, std::streamsize n)
+{ return impl::write(cur_, last_, s, n); }
+
+
+template<typename Mode, typename Range>
+std::streampos range_adapter<Mode, Range>::seek
+    (stream_offset off, BOOST_IOS::seekdir way)
+{ 
+    impl::seek(first_, cur_, last_, off, way); 
+    return offset_to_position(cur_ - first_);
+}
+
+//------------------Implementation of range_adapter_impl----------------------//
+
+template<>
+struct range_adapter_impl<std::forward_iterator_tag> {
+    template<typename Iter, typename Ch>
+    static std::streamsize read
+        (Iter& cur, Iter& last, Ch* s,std::streamsize n)
+    {
+        std::streamsize rem = n; // No. of chars remaining.
+        while (cur != last && rem-- > 0) *s++ = *cur++;
+        return n - rem != 0 ? n - rem : -1;
+    }
+
+    template<typename Iter, typename Ch>
+    static std::streamsize write
+        (Iter& cur, Iter& last, const Ch* s, std::streamsize n)
+    {
+        while (cur != last && n-- > 0) *cur++ = *s++;
+        if (cur == last && n > 0)
+            boost::throw_exception(write_area_exhausted());
+        return n;
+    }
+};
+
+template<>
+struct range_adapter_impl<std::random_access_iterator_tag> {
+    template<typename Iter, typename Ch>
+    static std::streamsize read
+        (Iter& cur, Iter& last, Ch* s,std::streamsize n)
+    {
+        std::streamsize result = 
+            (std::min)(static_cast<std::streamsize>(last - cur), n);
+        if (result)
+            std::copy(cur, cur + result, s);
+        cur += result;
+        return result != 0 ? result : -1;
+    }
+
+    template<typename Iter, typename Ch>
+    static std::streamsize write
+        (Iter& cur, Iter& last, const Ch* s, std::streamsize n)
+    {
+        std::streamsize count =
+            (std::min)(static_cast<std::streamsize>(last - cur), n);
+        std::copy(s, s + count, cur);
+        cur += count;
+        if (count < n) 
+            boost::throw_exception(write_area_exhausted());
+        return n;
+    }
+
+    template<typename Iter>
+    static void seek
+        ( Iter& first, Iter& cur, Iter& last, stream_offset off,
+          BOOST_IOS::seekdir way )
+    {
+        using namespace std;
+        switch (way) {
+        case BOOST_IOS::beg:
+            if (off > last - first || off < 0)
+                boost::throw_exception(bad_seek());
+            cur = first + off;
+            break;
+        case BOOST_IOS::cur:
+            {
+                std::ptrdiff_t newoff = cur - first + off;
+                if (newoff > last - first || newoff < 0)
+                    boost::throw_exception(bad_seek());
+                cur += off;
+                break;
+            }
+        case BOOST_IOS::end:
+            if (last - first + off < 0 || off > 0)
+                boost::throw_exception(bad_seek());
+            cur = last + off;
+            break;
+        default:
+            BOOST_ASSERT(0);
+        }
+    }
+};
+
+} } } // End namespaces detail, iostreams, boost.
+
+#include <boost/iostreams/detail/config/enable_warnings.hpp>  // MSVC.
+
+#endif // #ifndef BOOST_IOSTREAMS_DETAIL_RANGE_ADAPTER_HPP_INCLUDED //---------------//