add boost on mac

macx64/include/boost/beast/websocket/detail/soft_mutex.hpp

@@ -0,0 +1,112 @@
+//
+// 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
+//
+
+#ifndef BOOST_BEAST_WEBSOCKET_DETAIL_SOFT_MUTEX_HPP
+#define BOOST_BEAST_WEBSOCKET_DETAIL_SOFT_MUTEX_HPP
+
+#include <boost/assert.hpp>
+
+namespace boost {
+namespace beast {
+namespace websocket {
+namespace detail {
+
+// used to order reads, writes in websocket streams
+
+class soft_mutex
+{
+    int id_ = 0;
+
+public:
+    soft_mutex() = default;
+    soft_mutex(soft_mutex const&) = delete;
+    soft_mutex& operator=(soft_mutex const&) = delete;
+
+    soft_mutex(soft_mutex&& other) noexcept
+        : id_(boost::exchange(other.id_, 0))
+    {
+    }
+
+    soft_mutex& operator=(soft_mutex&& other) noexcept
+    {
+        id_ = other.id_;
+        other.id_ = 0;
+        return *this;
+    }
+
+    // VFALCO I'm not too happy that this function is needed
+    void
+    reset()
+    {
+        id_ = 0;
+    }
+
+    bool
+    is_locked() const noexcept
+    {
+        return id_ != 0;
+    }
+
+    template<class T>
+    bool
+    is_locked(T const*) const noexcept
+    {
+        return id_ == T::id;
+    }
+
+    template<class T>
+    void
+    lock(T const*)
+    {
+        BOOST_ASSERT(id_ == 0);
+        id_ = T::id;
+    }
+
+    template<class T>
+    void
+    unlock(T const*)
+    {
+        BOOST_ASSERT(id_ == T::id);
+        id_ = 0;
+    }
+
+    template<class T>
+    bool
+    try_lock(T const*)
+    {
+        // If this assert goes off it means you are attempting to
+        // simultaneously initiate more than one of same asynchronous
+        // operation, which is not allowed. For example, you must wait
+        // for an async_read to complete before performing another
+        // async_read.
+        //
+        BOOST_ASSERT(id_ != T::id);
+        if(id_ != 0)
+            return false;
+        id_ = T::id;
+        return true;
+    }
+
+    template<class T>
+    bool
+    try_unlock(T const*) noexcept
+    {
+        if(id_ != T::id)
+            return false;
+        id_ = 0;
+        return true;
+    }
+};
+
+} // detail
+} // websocket
+} // beast
+} // boost
+
+#endif