ceph/src/Beast/include/beast/zlib/detail/ranges.hpp

   1 //
   2 // Copyright (c) 2013-2017 Vinnie Falco (vinnie dot falco at gmail dot com)
   3 //
   4 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   5 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 //
   7 // This is a derivative work based on Zlib, copyright below:
   8 /*
   9     Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler
  10
  11     This software is provided 'as-is', without any express or implied
  12     warranty.  In no event will the authors be held liable for any damages
  13     arising from the use of this software.
  14
  15     Permission is granted to anyone to use this software for any purpose,
  16     including commercial applications, and to alter it and redistribute it
  17     freely, subject to the following restrictions:
  18
  19     1. The origin of this software must not be misrepresented; you must not
  20        claim that you wrote the original software. If you use this software
  21        in a product, an acknowledgment in the product documentation would be
  22        appreciated but is not required.
  23     2. Altered source versions must be plainly marked as such, and must not be
  24        misrepresented as being the original software.
  25     3. This notice may not be removed or altered from any source distribution.
  26
  27     Jean-loup Gailly        Mark Adler
  28     jloup@gzip.org          madler@alumni.caltech.edu
  29
  30     The data format used by the zlib library is described by RFCs (Request for
  31     Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950
  32     (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format).
  33 */
  34
  35 #ifndef BEAST_ZLIB_DETAIL_RANGES_HPP
  36 #define BEAST_ZLIB_DETAIL_RANGES_HPP
  37
  38 #include <cstdint>
  39 #include <type_traits>
  40
  41 namespace beast {
  42 namespace zlib {
  43 namespace detail {
  44
  45 struct ranges
  46 {
  47     template<bool isConst>
  48     struct range
  49     {
  50         using iter_t =
  51             typename std::conditional<isConst,
  52                 std::uint8_t const*,
  53                 std::uint8_t*>::type;
  54
  55         iter_t first;
  56         iter_t last;
  57         iter_t next;
  58
  59         // total bytes in range
  60         std::size_t
  61         size() const
  62         {
  63             return last - first;
  64         }
  65
  66         // bytes consumed
  67         std::size_t
  68         used() const
  69         {
  70             return next - first;
  71         }
  72
  73         // bytes remaining
  74         std::size_t
  75         avail() const
  76         {
  77             return last - next;
  78         }
  79     };
  80
  81     range<true> in;
  82     range<false> out;
  83 };
  84
  85 // Clamp u to v where u and v are different types
  86 template<class U, class V>
  87 inline
  88 U
  89 clamp(U u, V v)
  90 {
  91     if(u > v)
  92         u = static_cast<U>(v);
  93     return u;
  94 }
  95
  96 } // detail
  97 } // zlib
  98 } // beast
  99
 100 #endif