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-rw-r--r--nptl/cancellation.c92
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diff --git a/nptl/cancellation.c b/nptl/cancellation.c
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+/* Copyright (C) 2002 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <setjmp.h>
+#include <stdlib.h>
+#include "pthreadP.h"
+
+
+/* This function is responsible for calling all registered cleanup
+   handlers and then terminate the thread.  This includes dellocating
+   the thread-specific data.  The implementation is complicated by the
+   fact that we have to handle to cancellation handler registration
+   methods: exceptions using try/finally and setjmp.
+
+   The setjmp method is always available.  The user might compile some
+   code which uses this method because no modern compiler is
+   available.  So we have to handle these first since we cannot call
+   the cleanup handlers if the stack frames are gone.  At the same
+   time this opens a hole for the register exception handler blocks
+   since now they might be in danger of using an overwritten stack
+   frame.  The advise is to only use new or only old style cancellation
+   handling.  */
+void
+__do_cancel (char *currentframe)
+{
+  struct pthread *self = THREAD_SELF;
+
+  /* Cleanup the thread-local storage.  */
+  __cleanup_thread (self, currentframe);
+
+  /* Throw an exception.  */
+  // XXX TBI
+
+  /* If throwing an exception didn't work try the longjmp.  */
+  __libc_longjmp (self->cancelbuf, 1);
+
+  /* NOTREACHED */
+}
+
+
+void
+__cleanup_thread (struct pthread *self, char *currentframe)
+{
+  struct _pthread_cleanup_buffer *cleanups;
+
+  /* Call all registered cleanup handlers.  */
+  cleanups = THREAD_GETMEM (self, cleanup);
+  if (__builtin_expect (cleanups != NULL, 0))
+    {
+      struct _pthread_cleanup_buffer *last;
+
+      while (FRAME_LEFT (currentframe, cleanups))
+	{
+	  last = cleanups;
+	  cleanups = cleanups->__prev;
+
+	  if (cleanups == NULL || FRAME_LEFT (last, cleanups))
+	    {
+	      cleanups = NULL;
+	      break;
+	    }
+	}
+
+      while (cleanups != NULL)
+	{
+	  /* Call the registered cleanup function.  */
+	  cleanups->__routine (cleanups->__arg);
+
+	  last = cleanups;
+	  cleanups = cleanups->__prev;
+
+	  if (FRAME_LEFT (last, cleanups))
+	    break;
+	}
+    }
+}