ceph/src/boost/boost/align/detail/align.hpp

   1 /*
   2 Copyright 2014-2016 Glen Joseph Fernandes
   3 (glenjofe@gmail.com)
   4
   5 Distributed under the Boost Software License, Version 1.0.
   6 (http://www.boost.org/LICENSE_1_0.txt)
   7 */
   8 #ifndef BOOST_ALIGN_DETAIL_ALIGN_HPP
   9 #define BOOST_ALIGN_DETAIL_ALIGN_HPP
  10
  11 #include <boost/align/detail/is_alignment.hpp>
  12 #include <boost/assert.hpp>
  13
  14 namespace boost {
  15 namespace alignment {
  16
  17 inline void*
  18 align(std::size_t alignment, std::size_t size, void*& ptr,
  19     std::size_t& space)
  20 {
  21     BOOST_ASSERT(detail::is_alignment(alignment));
  22     if (size <= space) {
  23         char* p = reinterpret_cast<char*>(~(alignment - 1) &
  24             (reinterpret_cast<std::size_t>(ptr) + alignment - 1));
  25         std::size_t n = space - (p - static_cast<char*>(ptr));
  26         if (size <= n) {
  27             ptr = p;
  28             space = n;
  29             return p;
  30         }
  31     }
  32     return 0;
  33 }
  34
  35 } /* alignment */
  36 } /* boost */
  37
  38 #endif