From 52174bb4cc09ea59a998476ec4f7566409c6e4d0 Mon Sep 17 00:00:00 2001
From: Corinna Vinschen <corinna@vinschen.de>
Date: Wed, 30 May 2012 09:15:38 +0000
Subject: [PATCH] 	* thread.cc: Remove temporary newlib workaround, now
 that newlib 	handles thread cancellation by itself. 	(class
 __cygwin_lock_handler): Remove. 	(__cygwin_lock_cleanup): Remove. 
 (__cygwin_lock_lock): Revert newlib workaround, 
 (__cygwin_lock_trylock): Ditto. 	(__cygwin_lock_unlock): Ditto. 
 (pthread::pop_cleanup_handler): Ditto.

---
 winsup/cygwin/ChangeLog | 11 ++++++
 winsup/cygwin/thread.cc | 86 +----------------------------------------
 2 files changed, 12 insertions(+), 85 deletions(-)

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 79588781d..bfb69ab9e 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,14 @@
+2012-05-30  Corinna Vinschen  <corinna@vinschen.de>
+
+	* thread.cc: Remove temporary newlib workaround, now that newlib
+	handles thread cancellation by itself.
+	(class __cygwin_lock_handler): Remove.
+	(__cygwin_lock_cleanup): Remove.
+	(__cygwin_lock_lock): Revert newlib workaround,
+	(__cygwin_lock_trylock): Ditto.
+	(__cygwin_lock_unlock): Ditto.
+	(pthread::pop_cleanup_handler): Ditto.
+
 2012-05-29  Corinna Vinschen  <corinna@vinschen.de>
 
 	* select.cc (select_stuff::wait): Temporarily disable restarting
diff --git a/winsup/cygwin/thread.cc b/winsup/cygwin/thread.cc
index 8bf5135b6..b66bd4835 100644
--- a/winsup/cygwin/thread.cc
+++ b/winsup/cygwin/thread.cc
@@ -95,95 +95,23 @@ __cygwin_lock_fini (_LOCK_T *lock)
   pthread_mutex_destroy ((pthread_mutex_t*) lock);
 }
 
-#define WORKAROUND_NEWLIB
-
-#ifdef WORKAROUND_NEWLIB
-/* FIXME:
-
-   This cleanup stuff is necessary to harden Cygwin against thread
-   cancellation.  In theory, installing a cleanup handler is the task of
-   the calling function.
-
-   The problem here is that a lot of calling functions are in newlib's
-   stdio implementation.  So, the right thing to do would be to change
-   newlib's stdio functions to install the required pthread cleanup
-   handlers.
-
-   This is a bigger task than it sounds, so, as a temporary workaround,
-   what we do here is to install a cleanup handler in the lock function
-   itself and to cleanup in the unlock function.  This works around the
-   problem for the time being. */
-class __cygwin_lock_handler : public __pthread_cleanup_handler
-{
-public:
-  pthread_mutex_t *lock;
-
-  __cygwin_lock_handler (__cleanup_routine_type _fn, _LOCK_T *_lock)
-  {
-    function = _fn;
-    arg = this;
-    next = NULL;
-    lock = (pthread_mutex_t *) _lock;
-  }
-  void *operator new (size_t) __attribute__ ((nothrow))
-  {return cmalloc (HEAP_BUF, sizeof (__cygwin_lock_handler));}
-  void operator delete (void *p) { cfree (p); }
-};
-
-static void
-__cygwin_lock_cleanup (void *hdl)
-{
-  __cygwin_lock_handler *cleanup = (__cygwin_lock_handler *) hdl;
-  pthread_mutex_unlock (cleanup->lock);
-  delete cleanup;
-}
-#endif /* WORKAROUND_NEWLIB */
-
 extern "C" void
 __cygwin_lock_lock (_LOCK_T *lock)
 {
   paranoid_printf ("threadcount %d.  locking", MT_INTERFACE->threadcount);
-#ifdef WORKAROUND_NEWLIB
-  if (cygwin_finished_initializing)
-    {
-      __cygwin_lock_handler *cleanup
-	= new __cygwin_lock_handler (__cygwin_lock_cleanup, lock);
-      pthread::self ()->push_cleanup_handler (cleanup);
-    }
-#endif /* WORKAROUND_NEWLIB */
   pthread_mutex_lock ((pthread_mutex_t*) lock);
 }
 
 extern "C" int
 __cygwin_lock_trylock (_LOCK_T *lock)
 {
-#ifdef WORKAROUND_NEWLIB
-  if (cygwin_finished_initializing)
-    {
-      __cygwin_lock_handler *cleanup
-      	= new __cygwin_lock_handler (__cygwin_lock_cleanup, lock);
-      pthread::self ()->push_cleanup_handler (cleanup);
-      int ret = pthread_mutex_trylock ((pthread_mutex_t*) lock);
-      if (ret)
-	{
-	  pthread::self ()->pop_cleanup_handler (0);
-	  delete cleanup;
-	}
-      return ret;
-    }
-  else
-#endif /* WORKAROUND_NEWLIB */
   return pthread_mutex_trylock ((pthread_mutex_t*) lock);
 }
 
+
 extern "C" void
 __cygwin_lock_unlock (_LOCK_T *lock)
 {
-#ifdef WORKAROUND_NEWLIB
-  if (cygwin_finished_initializing)
-    pthread::self ()->pop_cleanup_handler (1);
-  else
-#endif /* WORKAROUND_NEWLIB */
   pthread_mutex_unlock ((pthread_mutex_t*) lock);
   paranoid_printf ("threadcount %d.  unlocked", MT_INTERFACE->threadcount);
 }
@@ -1159,22 +1087,10 @@ pthread::pop_cleanup_handler (int const execute)
   if (cleanup_stack != NULL)
     {
       __pthread_cleanup_handler *handler = cleanup_stack;
-#ifdef WORKAROUND_NEWLIB
-      /* We split out handler->next so we can set cleanup_stack to handler->next
-	 without relying on handler still existing.  This allows to delete the
-	 handler in the handler function.  For a description why we need that,
-	 at least temporarly, see the comment preceeding the definition of
-	 __cygwin_lock_handler earlier in this file. */
-      __pthread_cleanup_handler *next = handler->next;
 
-      if (execute)
-	(*handler->function) (handler->arg);
-      cleanup_stack = next;
-#else
       if (execute)
 	(*handler->function) (handler->arg);
       cleanup_stack = handler->next;
-#endif /* WORKAROUND_NEWLIB */
     }
 
   mutex.unlock ();