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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;
+ }
+ }
+}