re PR libstdc++/12658 (Thread safety problems in locale::global() and locale::locale())

2003-12-15  Benjamin Kosnik  <bkoz@redhat.com>

	PR libstdc++/12658
	* include/Makefile.am (bits_headers): Add concurrence.h.
	* include/Makefile.in: Regenerated.
	* include/bits/concurrence.h: New.
	* src/locale_init.cc: Use it.
	(locale::locale): Lock critical regions.
	(locale::global): Same.

From-SVN: r74648

libstdc++-v3/ChangeLog

@@ -1,3 +1,13 @@
+2003-12-15  Benjamin Kosnik  <bkoz@redhat.com>
+
+	PR libstdc++/12658
+	* include/Makefile.am (bits_headers): Add concurrence.h.
+	* include/Makefile.in: Regenerated.
+	* include/bits/concurrence.h: New.
+	* src/locale_init.cc: Use it.
+	(locale::locale): Lock critical regions.
+	(locale::global): Same.
+	
 2003-12-15  Benjamin Kosnik  <bkoz@redhat.com>
 
 	* include/bits/basic_string.h: Change _*_references to _*_refcount.

libstdc++-v3/include/Makefile.am

@@ -101,6 +101,7 @@ bits_headers = \
 	${bits_srcdir}/char_traits.h \
 	${bits_srcdir}/codecvt.h \
 	${bits_srcdir}/concept_check.h \
+	${bits_srcdir}/concurrence.h \
 	${bits_srcdir}/cpp_type_traits.h \
 	${bits_srcdir}/demangle.h \
 	${bits_srcdir}/deque.tcc \

libstdc++-v3/include/Makefile.in

@@ -296,6 +296,7 @@ bits_headers = \
 	${bits_srcdir}/char_traits.h \
 	${bits_srcdir}/codecvt.h \
 	${bits_srcdir}/concept_check.h \
+	${bits_srcdir}/concurrence.h \
 	${bits_srcdir}/cpp_type_traits.h \
 	${bits_srcdir}/demangle.h \
 	${bits_srcdir}/deque.tcc \
@@ -518,15 +519,15 @@ debug_headers = \
 	${debug_srcdir}/string \
 	${debug_srcdir}/vector
 
+@GLIBCXX_C_HEADERS_C_STD_FALSE@c_base_headers_extra = 
 
 # Some of the different "C" header models need extra files.
 # Some "C" header schemes require the "C" compatibility headers.
 # For --enable-cheaders=c_std
 @GLIBCXX_C_HEADERS_C_STD_TRUE@c_base_headers_extra = ${c_base_srcdir}/cmath.tcc
-@GLIBCXX_C_HEADERS_C_STD_FALSE@c_base_headers_extra = 
-@GLIBCXX_C_HEADERS_COMPATIBILITY_FALSE@c_compatibility_headers_extra = 
 
 @GLIBCXX_C_HEADERS_COMPATIBILITY_TRUE@c_compatibility_headers_extra = ${c_compatibility_headers}
+@GLIBCXX_C_HEADERS_COMPATIBILITY_FALSE@c_compatibility_headers_extra = 
 
 host_srcdir = ${glibcxx_srcdir}/$(OS_INC_SRCDIR)
 host_builddir = ./${host_alias}/bits

libstdc++-v3/include/bits/concurrence.h

@@ -0,0 +1,54 @@
+// Support for concurrent programing -*- C++ -*-
+
+// Copyright (C) 2003
+// 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.
+
+// As a special exception, you may use this file as part of a free software
+// library without restriction.  Specifically, if other files instantiate
+// templates or use macros or inline functions from this file, or you compile
+// this file and link it with other files to produce an executable, this
+// file does not by itself cause the resulting executable to be covered by
+// the GNU General Public License.  This exception does not however
+// invalidate any other reasons why the executable file might be covered by
+// the GNU General Public License.
+ 
+#ifndef _CONCURRENCE
+#define _CONCURRENCE 1
+
+// GCC's thread abstraction layer
+#include "bits/gthr.h"
+
+#if __GTHREADS
+# ifdef __GTHREAD_MUTEX_INIT
+#  define __glibcxx_mutex_define_initialized(NAME) \
+__gthread_mutex_t NAME = __GTHREAD_MUTEX_INIT
+# else
+#  define __glibcxx_mutex_define_initialized(NAME) \
+__gthread_mutex_t NAME; \
+__GTHREAD_MUTEX_INIT_FUNCTION(&NAME)
+# endif
+# define __glibcxx_mutex_lock(LOCK) __gthread_mutex_lock(&LOCK)
+# define __glibcxx_mutex_unlock(LOCK) __gthread_mutex_unlock(&LOCK)
+#else
+# define __glibcxx_mutex_define_initialized(NAME)
+# define __glibcxx_mutex_lock(LOCK) 
+# define __glibcxx_mutex_unlock(LOCK) 
+#endif
+
+#endif

libstdc++-v3/src/locale_init.cc

@@ -33,6 +33,7 @@
 #include <cwctype>     // For towupper, etc.
 #include <locale>
 #include <bits/atomicity.h>
+#include <bits/concurrence.h>
 
 namespace __gnu_cxx
 {
@@ -96,21 +97,26 @@ namespace std
   locale::locale() throw()
   { 
     _S_initialize(); 
-    (_M_impl = _S_global)->_M_add_reference(); 
+    __glibcxx_mutex_define_initialized(lock);
+    __glibcxx_mutex_lock(lock);
+    _S_global->_M_add_reference();
+    _M_impl = _S_global;
+    __glibcxx_mutex_unlock(lock);
   }
 
   locale
   locale::global(const locale& __other)
   {
     _S_initialize();
-
+    __glibcxx_mutex_define_initialized(lock);
-    // XXX MT
+    __glibcxx_mutex_lock(lock);
     _Impl* __old = _S_global;
     __other._M_impl->_M_add_reference();
     _S_global = __other._M_impl; 
     if (_S_global->_M_check_same_name() 
 	&& (std::strcmp(_S_global->_M_names[0], "*") != 0))
       setlocale(LC_ALL, __other.name().c_str());
+    __glibcxx_mutex_unlock(lock);
 
     // Reference count sanity check: one reference removed for the
     // subsition of __other locale, one added by return-by-value. Net