整理

include/boost/align/detail/align.hpp

@@ -0,0 +1,38 @@
+/*
+Copyright 2014-2020 Glen Joseph Fernandes
+(glenjofe@gmail.com)
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+*/
+#ifndef BOOST_ALIGN_DETAIL_ALIGN_HPP
+#define BOOST_ALIGN_DETAIL_ALIGN_HPP
+
+#include <boost/align/detail/is_alignment.hpp>
+#include <boost/assert.hpp>
+
+namespace boost {
+namespace alignment {
+
+inline void*
+align(std::size_t alignment, std::size_t size, void*& ptr,
+    std::size_t& space)
+{
+    BOOST_ASSERT(boost::alignment::detail::is_alignment(alignment));
+    if (size <= space) {
+        char* p = reinterpret_cast<char*>(~(alignment - 1) &
+            (reinterpret_cast<std::size_t>(ptr) + alignment - 1));
+        std::size_t n = p - static_cast<char*>(ptr);
+        if (n <= space - size) {
+            ptr = p;
+            space -= n;
+            return p;
+        }
+    }
+    return 0;
+}
+
+} /* alignment */
+} /* boost */
+
+#endif