整理

include/boost/system/detail/mutex.hpp

@@ -0,0 +1,128 @@
+#ifndef BOOST_SYSTEM_DETAIL_MUTEX_HPP_INCLUDED
+#define BOOST_SYSTEM_DETAIL_MUTEX_HPP_INCLUDED
+
+// Copyright 2023 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt)
+
+#include <boost/config.hpp>
+
+#if defined(BOOST_SYSTEM_DISABLE_THREADS)
+
+namespace boost
+{
+namespace system
+{
+namespace detail
+{
+
+struct mutex
+{
+    void lock()
+    {
+    }
+
+    void unlock()
+    {
+    }
+};
+
+} // namespace detail
+} // namespace system
+} // namespace boost
+
+#else // defined(BOOST_SYSTEM_DISABLE_THREADS)
+
+#if defined(BOOST_MSSTL_VERSION) && BOOST_MSSTL_VERSION >= 140
+
+// Under the MS STL, std::mutex::mutex() is not constexpr, as is
+// required by the standard, which leads to initialization order
+// issues. However, shared_mutex is based on SRWLock and its
+// default constructor is constexpr, so we use that instead.
+
+#include <boost/winapi/config.hpp>
+
+// SRWLOCK is not available when targeting Windows XP
+#if BOOST_USE_WINAPI_VERSION >= BOOST_WINAPI_VERSION_WIN6
+
+#include <shared_mutex>
+
+#if BOOST_MSSTL_VERSION >= 142 || _HAS_SHARED_MUTEX
+# define BOOST_SYSTEM_HAS_MSSTL_SHARED_MUTEX
+#endif
+
+#endif // BOOST_MSSTL_VERSION >= 142 || _HAS_SHARED_MUTEX
+
+#endif // BOOST_USE_WINAPI_VERSION >= BOOST_WINAPI_VERSION_WIN6
+
+#if defined(BOOST_SYSTEM_HAS_MSSTL_SHARED_MUTEX)
+
+namespace boost
+{
+namespace system
+{
+namespace detail
+{
+
+typedef std::shared_mutex mutex;
+
+} // namespace detail
+} // namespace system
+} // namespace boost
+
+#else // defined(BOOST_SYSTEM_HAS_MSSTL_SHARED_MUTEX)
+
+#include <mutex>
+
+namespace boost
+{
+namespace system
+{
+namespace detail
+{
+
+using std::mutex;
+
+} // namespace detail
+} // namespace system
+} // namespace boost
+
+#endif // defined(BOOST_SYSTEM_HAS_MSSTL_SHARED_MUTEX)
+#endif // defined(BOOST_SYSTEM_DISABLE_THREADS)
+
+namespace boost
+{
+namespace system
+{
+namespace detail
+{
+
+template<class Mtx> class lock_guard
+{
+private:
+
+    Mtx& mtx_;
+
+private:
+
+    lock_guard( lock_guard const& );
+    lock_guard& operator=( lock_guard const& );
+
+public:
+
+    explicit lock_guard( Mtx& mtx ): mtx_( mtx )
+    {
+        mtx_.lock();
+    }
+
+    ~lock_guard()
+    {
+        mtx_.unlock();
+    }
+};
+
+} // namespace detail
+} // namespace system
+} // namespace boost
+
+#endif // #ifndef BOOST_SYSTEM_DETAIL_MUTEX_HPP_INCLUDED