[Boost-commit] svn:boost r63795 - trunk/boost/thread/win32

Subject: [Boost-commit] svn:boost r63795 - trunk/boost/thread/win32
From: anthony_at_[hidden]
Date: 2010-07-09 17:15:58

Author: anthonyw
Date: 2010-07-09 17:15:57 EDT (Fri, 09 Jul 2010)
New Revision: 63795
URL: http://svn.boost.org/trac/boost/changeset/63795

Log:
Fix for issue #4225 to allow static initialization of boost::once_flag
Text files modified: 
   trunk/boost/thread/win32/once.hpp              |   118 +++++++++++++++++++++++++-------------- 
   trunk/boost/thread/win32/thread_primitives.hpp |     8 ++                                      
   2 files changed, 82 insertions(+), 44 deletions(-)

Modified: trunk/boost/thread/win32/once.hpp
==============================================================================
--- trunk/boost/thread/win32/once.hpp	(original)
+++ trunk/boost/thread/win32/once.hpp	2010-07-09 17:15:57 EDT (Fri, 09 Jul 2010)
@@ -35,41 +35,85 @@
         long status;
         long count;
         long throw_count;
-        void* event_handle;
+    };
+
+#define BOOST_ONCE_INIT {0,0,0}
+
+    namespace detail
+    {
+#ifdef BOOST_NO_ANSI_APIS
+        typedef wchar_t once_char_type;
+#else
+        typedef char once_char_type;
+#endif
+        unsigned const once_mutex_name_fixed_length=54;
+        unsigned const once_mutex_name_length=once_mutex_name_fixed_length+
+            sizeof(void*)*2+sizeof(unsigned long)*2+1;
 
-        ~once_flag()
+        template <class I>
+        void int_to_string(I p, once_char_type* buf)
         {
-            if(count)
+            for(unsigned i=0; i < sizeof(I)*2; ++i,++buf)
             {
-                BOOST_ASSERT(count==throw_count);
+#ifdef BOOST_NO_ANSI_APIS
+                once_char_type const a=L'A';
+#else
+                once_char_type const a='A';
+#endif
+                *buf = a + static_cast<once_char_type>((p >> (i*4)) & 0x0f);
             }
+            *buf = 0;
+        }
+
+        inline void name_once_mutex(once_char_type* mutex_name,void* flag_address)
+        {
+#ifdef BOOST_NO_ANSI_APIS
+            static const once_char_type fixed_mutex_name[]=L"Local\\{C15730E2-145C-4c5e-B005-3BC753F42475}-once-flag";
+#else
+            static const once_char_type fixed_mutex_name[]="Local\\{C15730E2-145C-4c5e-B005-3BC753F42475}-once-flag";
+#endif
+            BOOST_STATIC_ASSERT(sizeof(fixed_mutex_name) == 
+                                (sizeof(once_char_type)*(once_mutex_name_fixed_length+1)));
             
-            void* const old_event=BOOST_INTERLOCKED_EXCHANGE_POINTER(&event_handle,0);
-            if(old_event)
+            std::memcpy(mutex_name,fixed_mutex_name,sizeof(fixed_mutex_name));
+            detail::int_to_string(reinterpret_cast<std::ptrdiff_t>(flag_address), 
+                                  mutex_name + once_mutex_name_fixed_length);
+            detail::int_to_string(win32::GetCurrentProcessId(), 
+                                  mutex_name + once_mutex_name_fixed_length + sizeof(void*)*2);
+        }
+                        
+        inline void* open_once_event(once_char_type* mutex_name,void* flag_address)
+        {
+            if(!*mutex_name)
             {
-                ::boost::detail::win32::CloseHandle(old_event);
+                name_once_mutex(mutex_name,flag_address);
             }
+            
+#ifdef BOOST_NO_ANSI_APIS                        
+            return ::boost::detail::win32::OpenEventW(
+#else
+            return ::boost::detail::win32::OpenEventA(
+#endif
+                ::boost::detail::win32::synchronize | 
+                ::boost::detail::win32::event_modify_state,
+                false,
+                mutex_name);
         }
-    };
-
-#define BOOST_ONCE_INIT {0,0,0,0}
 
-    namespace detail
-    {
-        inline void* allocate_event_handle(void*& handle)
+        inline void* create_once_event(once_char_type* mutex_name,void* flag_address)
         {
-            void* const new_handle=::boost::detail::win32::create_anonymous_event(
-                ::boost::detail::win32::manual_reset_event,
-                ::boost::detail::win32::event_initially_reset);
-            
-            void* event_handle=BOOST_INTERLOCKED_COMPARE_EXCHANGE_POINTER(&handle,
-                                                                          new_handle,0);
-            if(event_handle)
+            if(!*mutex_name)
             {
-                ::boost::detail::win32::CloseHandle(new_handle);
-                return event_handle;
+                name_once_mutex(mutex_name,flag_address);
             }
-            return new_handle;
+#ifdef BOOST_NO_ANSI_APIS                        
+            return ::boost::detail::win32::CreateEventW(
+#else
+            return ::boost::detail::win32::CreateEventA(
+#endif
+                0,::boost::detail::win32::manual_reset_event,
+                ::boost::detail::win32::event_initially_reset,
+                mutex_name);
         }
     }
     
@@ -83,8 +127,10 @@
         long const running_value=0x7f0725e3;
         long status;
         bool counted=false;
-        void* event_handle=0;
+        detail::win32::handle_manager event_handle;
         long throw_count=0;
+        detail::once_char_type mutex_name[detail::once_mutex_name_length];
+        mutex_name[0]=0;
 
         while((status=::boost::detail::interlocked_read_acquire(&flag.status))
               !=function_complete_flag_value)
@@ -96,7 +142,7 @@
                 {
                     if(!event_handle)
                     {
-                        event_handle=::boost::detail::interlocked_read_acquire(&flag.event_handle);
+                        event_handle=detail::open_once_event(mutex_name,&flag);
                     }
                     if(event_handle)
                     {
@@ -112,7 +158,7 @@
                     if(!event_handle && 
                        (::boost::detail::interlocked_read_acquire(&flag.count)>1))
                     {
-                        event_handle=::boost::detail::allocate_event_handle(flag.event_handle);
+                        event_handle=detail::create_once_event(mutex_name,&flag);
                     }
                     if(event_handle)
                     {
@@ -130,7 +176,7 @@
                     BOOST_INTERLOCKED_EXCHANGE(&flag.status,0);
                     if(!event_handle)
                     {
-                        event_handle=::boost::detail::interlocked_read_acquire(&flag.event_handle);
+                        event_handle=detail::open_once_event(mutex_name,&flag);
                     }
                     if(event_handle)
                     {
@@ -149,31 +195,15 @@
                 {
                     break;
                 }
-                event_handle=::boost::detail::interlocked_read_acquire(&flag.event_handle);
                 if(!event_handle)
                 {
-                    event_handle=::boost::detail::allocate_event_handle(flag.event_handle);
+                    event_handle=detail::create_once_event(mutex_name,&flag);
                     continue;
                 }
             }
             BOOST_VERIFY(!::boost::detail::win32::WaitForSingleObject(
                              event_handle,::boost::detail::win32::infinite));
         }
-        if(counted || throw_count)
-        {
-            if(!BOOST_INTERLOCKED_EXCHANGE_ADD(&flag.count,(counted?-1:0)-throw_count))
-            {
-                if(!event_handle)
-                {
-                    event_handle=::boost::detail::interlocked_read_acquire(&flag.event_handle);
-                }
-                if(event_handle)
-                {
-                    BOOST_INTERLOCKED_EXCHANGE_POINTER(&flag.event_handle,0);
-                    ::boost::detail::win32::CloseHandle(event_handle);
-                }
-            }
-        }
     }
 }
 

Modified: trunk/boost/thread/win32/thread_primitives.hpp
==============================================================================
--- trunk/boost/thread/win32/thread_primitives.hpp	(original)
+++ trunk/boost/thread/win32/thread_primitives.hpp	2010-07-09 17:15:57 EDT (Fri, 09 Jul 2010)
@@ -31,14 +31,18 @@
             unsigned const infinite=INFINITE;
             unsigned const timeout=WAIT_TIMEOUT;
             handle const invalid_handle_value=INVALID_HANDLE_VALUE;
+            unsigned const event_modify_state=EVENT_MODIFY_STATE;
+            unsigned const synchronize=SYNCHRONIZE;
 
 # ifdef BOOST_NO_ANSI_APIS
             using ::CreateMutexW;
             using ::CreateEventW;
+            using ::OpenEventW;
             using ::CreateSemaphoreW;
 # else
             using ::CreateMutexA;
             using ::CreateEventA;
+            using ::OpenEventA;
             using ::CreateSemaphoreA;
 # endif
             using ::CloseHandle;
@@ -100,6 +104,8 @@
             unsigned const infinite=~0U;
             unsigned const timeout=258U;
             handle const invalid_handle_value=(handle)(-1);
+            unsigned const event_modify_state=2;
+            unsigned const synchronize=0x100000u;
 
             extern "C"
             {
@@ -108,10 +114,12 @@
                 __declspec(dllimport) void* __stdcall CreateMutexW(_SECURITY_ATTRIBUTES*,int,wchar_t const*);
                 __declspec(dllimport) void* __stdcall CreateSemaphoreW(_SECURITY_ATTRIBUTES*,long,long,wchar_t const*);
                 __declspec(dllimport) void* __stdcall CreateEventW(_SECURITY_ATTRIBUTES*,int,int,wchar_t const*);
+                __declspec(dllimport) void* __stdcall OpenEventW(unsigned long,int,wchar_t const*);
 # else
                 __declspec(dllimport) void* __stdcall CreateMutexA(_SECURITY_ATTRIBUTES*,int,char const*);
                 __declspec(dllimport) void* __stdcall CreateSemaphoreA(_SECURITY_ATTRIBUTES*,long,long,char const*);
                 __declspec(dllimport) void* __stdcall CreateEventA(_SECURITY_ATTRIBUTES*,int,int,char const*);
+                __declspec(dllimport) void* __stdcall OpenEventA(unsigned long,int,char const*);
 # endif
                 __declspec(dllimport) int __stdcall CloseHandle(void*);
                 __declspec(dllimport) int __stdcall ReleaseMutex(void*);