From f306dcc391f33197b9ffd4ece11ec950be1c349b Mon Sep 17 00:00:00 2001
From: Oliver Kowalke <oliver.kowalke@gmx.de>
Date: Sat, 15 Dec 2012 14:36:39 +0100
Subject: [PATCH] scheduler::swap()

---
 include/boost/fiber/scheduler.hpp |  2 ++
 src/scheduler.cpp                 |  6 ++++++
 test/test_fiber.cpp               | 12 ++++++++++++
 3 files changed, 20 insertions(+)

diff --git a/include/boost/fiber/scheduler.hpp b/include/boost/fiber/scheduler.hpp
index 239abaeb..28a98deb 100644
--- a/include/boost/fiber/scheduler.hpp
+++ b/include/boost/fiber/scheduler.hpp
@@ -100,6 +100,8 @@ private:
 public:
     static scheduler & instance();
 
+    static void swap( scheduler *) BOOST_NOEXCEPT;
+
     virtual void spawn( detail::fiber_base::ptr_t const&) = 0;
 
     virtual void join( detail::fiber_base::ptr_t const&) = 0;
diff --git a/src/scheduler.cpp b/src/scheduler.cpp
index adac06a1..95b28fd4 100644
--- a/src/scheduler.cpp
+++ b/src/scheduler.cpp
@@ -5,6 +5,8 @@
 
 #define BOOST_FIBERS_SOURCE
 
+#include <algorithm>
+
 #include <boost/fiber/scheduler.hpp>
 
 #include <boost/fiber/detail/default_scheduler.hpp>
@@ -32,6 +34,10 @@ scheduler::instance()
 	return * instance_;
 }
 
+void
+scheduler::swap( scheduler * sched)
+{ std::swap( instance_, sched); }
+
 }}
 
 #ifdef BOOST_HAS_ABI_HEADERS
diff --git a/test/test_fiber.cpp b/test/test_fiber.cpp
index c6ea83e0..16c2bf01 100644
--- a/test/test_fiber.cpp
+++ b/test/test_fiber.cpp
@@ -14,6 +14,7 @@
 #include <boost/utility.hpp>
 
 #include <boost/fiber/all.hpp>
+#include <boost/fiber/detail/default_scheduler.hpp>
 
 namespace stm = boost::fibers;
 namespace this_stm = boost::this_fiber;
@@ -180,6 +181,16 @@ void test_detach()
     BOOST_CHECK( ! s2);
 }
 
+void test_swap()
+{
+    stm::scheduler::swap(
+        new stm::detail::default_scheduler() );
+    stm::fiber s1( f1);
+    BOOST_CHECK( ! s1);
+    stm::fiber s2( f2);
+    BOOST_CHECK( s2);
+}
+
 void test_complete()
 {
     stm::fiber s1( f1);
@@ -330,6 +341,7 @@ boost::unit_test::test_suite * init_unit_test_suite( int, char* [])
     test->add( BOOST_TEST_CASE( & test_id) );
     test->add( BOOST_TEST_CASE( & test_detach) );
     test->add( BOOST_TEST_CASE( & test_complete) );
+    test->add( BOOST_TEST_CASE( & test_swap) );
     test->add( BOOST_TEST_CASE( & test_cancel) );
     test->add( BOOST_TEST_CASE( & test_join) );
     test->add( BOOST_TEST_CASE( & test_yield_break) );