Rearrange sources (#4997)

include/xrpl/beast/utility/rngfill.h

@@ -0,0 +1,80 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of Beast: https://github.com/vinniefalco/Beast
+    Copyright 2014, Vinnie Falco <vinnie.falco@gmail.com>
+
+    Permission to use, copy, modify, and/or distribute this software for any
+    purpose  with  or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#ifndef BEAST_RANDOM_RNGFILL_H_INCLUDED
+#define BEAST_RANDOM_RNGFILL_H_INCLUDED
+
+#include <array>
+#include <cassert>
+#include <cstdint>
+#include <cstring>
+#include <type_traits>
+
+namespace beast {
+
+template <class Generator>
+void
+rngfill(void* buffer, std::size_t bytes, Generator& g)
+{
+    using result_type = typename Generator::result_type;
+
+    while (bytes >= sizeof(result_type))
+    {
+        auto const v = g();
+        std::memcpy(buffer, &v, sizeof(v));
+        buffer = reinterpret_cast<std::uint8_t*>(buffer) + sizeof(v);
+        bytes -= sizeof(v);
+    }
+
+    assert(bytes < sizeof(result_type));
+
+#ifdef __GNUC__
+    // gcc 11.1 (falsely) warns about an array-bounds overflow in release mode.
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Warray-bounds"
+#endif
+
+    if (bytes > 0)
+    {
+        auto const v = g();
+        std::memcpy(buffer, &v, bytes);
+    }
+
+#ifdef __GNUC__
+#pragma GCC diagnostic pop
+#endif
+}
+
+template <
+    class Generator,
+    std::size_t N,
+    class = std::enable_if_t<N % sizeof(typename Generator::result_type) == 0>>
+void
+rngfill(std::array<std::uint8_t, N>& a, Generator& g)
+{
+    using result_type = typename Generator::result_type;
+    auto i = N / sizeof(result_type);
+    result_type* p = reinterpret_cast<result_type*>(a.data());
+    while (i--)
+        *p++ = g();
+}
+
+}  // namespace beast
+
+#endif