externals: Update boost to 1.72 and add Boost Context

boost/thread/executors/executor.hpp

@@ -0,0 +1,150 @@
+// Copyright (C) 2013,2014 Vicente J. Botet Escriba
+//
+//  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)
+//
+// 2013/09 Vicente J. Botet Escriba
+//    Adapt to boost from CCIA C++11 implementation
+
+#ifndef BOOST_THREAD_EXECUTORS_EXECUTOR_HPP
+#define BOOST_THREAD_EXECUTORS_EXECUTOR_HPP
+
+#include <boost/thread/detail/config.hpp>
+#if defined BOOST_THREAD_PROVIDES_FUTURE_CONTINUATION && defined BOOST_THREAD_PROVIDES_EXECUTORS && defined BOOST_THREAD_USES_MOVE
+
+#include <boost/thread/detail/delete.hpp>
+#include <boost/thread/detail/move.hpp>
+#include <boost/thread/executors/work.hpp>
+
+#include <boost/config/abi_prefix.hpp>
+
+namespace boost
+{
+  namespace executors
+  {
+  class executor
+  {
+  public:
+    /// type-erasure to store the works to do
+    typedef  executors::work work;
+
+    /// executor is not copyable.
+    BOOST_THREAD_NO_COPYABLE(executor)
+    executor() {}
+
+    /**
+     * \par Effects
+     * Destroys the executor.
+     *
+     * \par Synchronization
+     * The completion of all the closures happen before the completion of the executor destructor.
+     */
+    virtual ~executor() {}
+
+    /**
+     * \par Effects
+     * Close the \c executor for submissions.
+     * The worker threads will work until there is no more closures to run.
+     */
+    virtual void close() = 0;
+
+    /**
+     * \par Returns
+     * Whether the pool is closed for submissions.
+     */
+    virtual bool closed() = 0;
+
+    /**
+     * \par Effects
+     * The specified closure will be scheduled for execution at some point in the future.
+     * If invoked closure throws an exception the executor will call std::terminate, as is the case with threads.
+     *
+     * \par Synchronization
+     * Ccompletion of closure on a particular thread happens before destruction of thread's thread local variables.
+     *
+     * \par Throws
+     * \c sync_queue_is_closed if the thread pool is closed.
+     * Whatever exception that can be throw while storing the closure.
+     */
+    virtual void submit(BOOST_THREAD_RV_REF(work) closure) = 0;
+//    virtual void submit(work& closure) = 0;
+
+    /**
+     * \par Requires
+     * \c Closure is a model of Callable(void()) and a model of CopyConstructible/MoveConstructible.
+     *
+     * \par Effects
+     * The specified closure will be scheduled for execution at some point in the future.
+     * If invoked closure throws an exception the thread pool will call std::terminate, as is the case with threads.
+     *
+     * \par Synchronization
+     * Completion of closure on a particular thread happens before destruction of thread's thread local variables.
+     *
+     * \par Throws
+     * \c sync_queue_is_closed if the thread pool is closed.
+     * Whatever exception that can be throw while storing the closure.
+     */
+
+#if defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+    template <typename Closure>
+    void submit(Closure & closure)
+    {
+      work w ((closure));
+      submit(boost::move(w));
+    }
+#endif
+    void submit(void (*closure)())
+    {
+      work w ((closure));
+      submit(boost::move(w));
+    }
+
+    template <typename Closure>
+    void submit(BOOST_THREAD_FWD_REF(Closure) closure)
+    {
+      //submit(work(boost::forward<Closure>(closure)));
+      work w((boost::forward<Closure>(closure)));
+      submit(boost::move(w));
+    }
+
+    /**
+     * \par Effects
+     * Try to execute one task.
+     *
+     * \par Returns
+     * Whether a task has been executed.
+     *
+     * \par Throws
+     * Whatever the current task constructor throws or the task() throws.
+     */
+    virtual bool try_executing_one() = 0;
+
+    /**
+     * \par Requires
+     * This must be called from an scheduled task.
+     *
+     * \par Effects
+     * Reschedule functions until pred()
+     */
+    template <typename Pred>
+    bool reschedule_until(Pred const& pred)
+    {
+      do {
+        //schedule_one_or_yield();
+        if ( ! try_executing_one())
+        {
+          return false;
+        }
+      } while (! pred());
+      return true;
+    }
+  };
+
+  }
+  using executors::executor;
+}
+
+#include <boost/config/abi_suffix.hpp>
+
+#endif
+#endif