From 8bf4eeece3076a35dbfe8d7385b4fef2488337d6 Mon Sep 17 00:00:00 2001
From: Dimitris Vyzovitis <vyzo@media.mit.edu>
Date: Wed, 3 Oct 2001 21:19:31 +0000
Subject: [PATCH] stl_threads.h (_Atomic_swap): New function.

	    * include/bits/stl_threads.h (_Atomic_swap): New function.
	    (_Swap_lock_struct<__dummy>::_S_swap_lock): New data.
	    * testsuite/ext/rope.cc: New file.

From-SVN: r45999
---
 libstdc++-v3/ChangeLog                  |  6 ++++
 libstdc++-v3/include/bits/stl_threads.h | 22 ++++++++++++++
 libstdc++-v3/testsuite/ext/rope.cc      | 38 +++++++++++++++++++++++++
 3 files changed, 66 insertions(+)
 create mode 100644 libstdc++-v3/testsuite/ext/rope.cc

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 65ec49e084f..bff34125434 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,9 @@
+2001-10-03  Dimitris Vyzovitis  <vyzo@media.mit.edu>
+
+	    * include/bits/stl_threads.h (_Atomic_swap): New function.
+	    (_Swap_lock_struct<__dummy>::_S_swap_lock): New data.
+	    * testsuite/ext/rope.cc: New file.
+
 2001-10-02  Benjamin Kosnik  <bkoz@redhat.com>
 
 	* config/locale/time_members_gnu.h: Remove.
diff --git a/libstdc++-v3/include/bits/stl_threads.h b/libstdc++-v3/include/bits/stl_threads.h
index b1278c1817f..dd27422f5c0 100644
--- a/libstdc++-v3/include/bits/stl_threads.h
+++ b/libstdc++-v3/include/bits/stl_threads.h
@@ -202,6 +202,28 @@ struct _Refcount_Base
 // later, if required.  You can start by cloning the __STL_PTHREADS
 // path while making the obvious changes.  Later it could be optimized
 // to use the atomicity.h abstraction layer from libstdc++-v3.
+// vyzo: simple _Atomic_swap implementation following the guidelines above
+       // We use a template here only to get a unique initialized instance.
+    template<int __dummy>
+    struct _Swap_lock_struct {
+        static __gthread_mutex_t _S_swap_lock;
+    };
+
+    template<int __dummy>
+    __gthread_mutex_t
+    _Swap_lock_struct<__dummy>::_S_swap_lock = __GTHREAD_MUTEX_INIT;
+
+    // This should be portable, but performance is expected
+    // to be quite awful.  This really needs platform specific
+    // code.
+    inline unsigned long _Atomic_swap(unsigned long * __p, unsigned long __q) {
+        __gthread_mutex_lock(&_Swap_lock_struct<0>::_S_swap_lock);
+        unsigned long __result = *__p;
+        *__p = __q;
+        __gthread_mutex_unlock(&_Swap_lock_struct<0>::_S_swap_lock);
+        return __result;
+    }
+
 #else
 // GCC extension end
 # ifdef __STL_SGI_THREADS
diff --git a/libstdc++-v3/testsuite/ext/rope.cc b/libstdc++-v3/testsuite/ext/rope.cc
new file mode 100644
index 00000000000..79eecf822b5
--- /dev/null
+++ b/libstdc++-v3/testsuite/ext/rope.cc
@@ -0,0 +1,38 @@
+// 2001-10-03 From: Dimitris Vyzovitis <vyzo@media.mit.edu>
+
+// Copyright (C) 2001 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+// USA.
+
+// rope (SGI extension)
+
+#include <ext/rope>
+#include <iostream>
+
+void test01()
+{
+  std::crope foo;
+  foo += "bar";
+  const char* data = foo.c_str();
+  std::cout << data << std::endl;
+}
+
+int main()
+{
+  test01();
+  return 0;
+}