add boost on mac

macx64/include/boost/beast/zlib/detail/bitstream.hpp

@@ -0,0 +1,201 @@
+//
+// Copyright (c) 2016-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
+//
+// 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)
+//
+// Official repository: https://github.com/boostorg/beast
+//
+// This is a derivative work based on Zlib, copyright below:
+/*
+    Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler
+
+    This software is provided 'as-is', without any express or implied
+    warranty.  In no event will the authors be held liable for any damages
+    arising from the use of this software.
+
+    Permission is granted to anyone to use this software for any purpose,
+    including commercial applications, and to alter it and redistribute it
+    freely, subject to the following restrictions:
+
+    1. The origin of this software must not be misrepresented; you must not
+       claim that you wrote the original software. If you use this software
+       in a product, an acknowledgment in the product documentation would be
+       appreciated but is not required.
+    2. Altered source versions must be plainly marked as such, and must not be
+       misrepresented as being the original software.
+    3. This notice may not be removed or altered from any source distribution.
+
+    Jean-loup Gailly        Mark Adler
+    jloup@gzip.org          madler@alumni.caltech.edu
+
+    The data format used by the zlib library is described by RFCs (Request for
+    Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950
+    (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format).
+*/
+
+#ifndef BOOST_BEAST_ZLIB_DETAIL_BITSTREAM_HPP
+#define BOOST_BEAST_ZLIB_DETAIL_BITSTREAM_HPP
+
+#include <boost/assert.hpp>
+#include <cstdint>
+#include <iterator>
+
+namespace boost {
+namespace beast {
+namespace zlib {
+namespace detail {
+
+class bitstream
+{
+    using value_type = std::uint32_t;
+
+    value_type v_ = 0;
+    unsigned n_ = 0;
+
+public:
+    // returns the number of bits in the reservoir
+    unsigned
+    size() const
+    {
+        return n_;
+    }
+
+    // discard n bits
+    void
+    drop(std::size_t n)
+    {
+        BOOST_ASSERT(n <= n_);
+        n_ -= static_cast<unsigned>(n);
+        v_ >>= n;
+    }
+
+    // flush everything
+    void
+    flush()
+    {
+        n_ = 0;
+        v_ = 0;
+    }
+
+    // flush to the next byte boundary
+    void
+    flush_byte()
+    {
+        drop(n_ % 8);
+    }
+
+    // ensure at least n bits
+    template<class FwdIt>
+    bool
+    fill(std::size_t n, FwdIt& first, FwdIt const& last);
+
+    // fill 8 bits, unchecked
+    template<class FwdIt>
+    void
+    fill_8(FwdIt& it);
+
+    // fill 16 bits, unchecked
+    template<class FwdIt>
+    void
+    fill_16(FwdIt& it);
+
+    // return n bits
+    template<class Unsigned>
+    void
+    peek(Unsigned& value, std::size_t n);
+
+    // return everything in the reservoir
+    value_type
+    peek_fast() const
+    {
+        return v_;
+    }
+
+    // return n bits, and consume
+    template<class Unsigned>
+    void
+    read(Unsigned& value, std::size_t n);
+
+    // rewind by the number of whole bytes stored (unchecked)
+    template<class BidirIt>
+    void
+    rewind(BidirIt& it);
+};
+
+template<class FwdIt>
+bool
+bitstream::
+fill(std::size_t n, FwdIt& first, FwdIt const& last)
+{
+    while(n_ < n)
+    {
+        if(first == last)
+            return false;
+        v_ += static_cast<value_type>(*first++) << n_;
+        n_ += 8;
+    }
+    return true;
+}
+
+template<class FwdIt>
+void
+bitstream::
+fill_8(FwdIt& it)
+{
+    v_ += static_cast<value_type>(*it++) << n_;
+    n_ += 8;
+}
+
+template<class FwdIt>
+void
+bitstream::
+fill_16(FwdIt& it)
+{
+    v_ += static_cast<value_type>(*it++) << n_;
+    n_ += 8;
+    v_ += static_cast<value_type>(*it++) << n_;
+    n_ += 8;
+}
+
+template<class Unsigned>
+void
+bitstream::
+peek(Unsigned& value, std::size_t n)
+{
+    BOOST_ASSERT(n <= sizeof(value)*8);
+    BOOST_ASSERT(n <= n_);
+    value = static_cast<Unsigned>(
+        v_ & ((1ULL << n) - 1));
+}
+
+template<class Unsigned>
+void
+bitstream::
+read(Unsigned& value, std::size_t n)
+{
+    BOOST_ASSERT(n < sizeof(v_)*8);
+    BOOST_ASSERT(n <= n_);
+    value = static_cast<Unsigned>(
+        v_ & ((1ULL << n) - 1));
+    v_ >>= n;
+    n_ -= static_cast<unsigned>(n);
+}
+
+template<class BidirIt>
+void
+bitstream::
+rewind(BidirIt& it)
+{
+    auto len = n_ >> 3;
+    it = std::prev(it, len);
+    n_ &= 7;
+    v_ &= (1U << n_) - 1;
+}
+
+} // detail
+} // zlib
+} // beast
+} // boost
+
+#endif