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-rw-r--r--REORG.TODO/nptl/pthread_setcanceltype.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/REORG.TODO/nptl/pthread_setcanceltype.c b/REORG.TODO/nptl/pthread_setcanceltype.c
new file mode 100644
index 0000000000..dd1f374849
--- /dev/null
+++ b/REORG.TODO/nptl/pthread_setcanceltype.c
@@ -0,0 +1,76 @@
+/* Copyright (C) 2002-2017 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, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include "pthreadP.h"
+#include <atomic.h>
+
+
+int
+__pthread_setcanceltype (int type, int *oldtype)
+{
+ if (type < PTHREAD_CANCEL_DEFERRED || type > PTHREAD_CANCEL_ASYNCHRONOUS)
+ return EINVAL;
+
+#ifndef SIGCANCEL
+ if (type == PTHREAD_CANCEL_ASYNCHRONOUS)
+ return ENOTSUP;
+#endif
+
+ volatile struct pthread *self = THREAD_SELF;
+
+ int oldval = THREAD_GETMEM (self, cancelhandling);
+ while (1)
+ {
+ int newval = (type == PTHREAD_CANCEL_ASYNCHRONOUS
+ ? oldval | CANCELTYPE_BITMASK
+ : oldval & ~CANCELTYPE_BITMASK);
+
+ /* Store the old value. */
+ if (oldtype != NULL)
+ *oldtype = ((oldval & CANCELTYPE_BITMASK)
+ ? PTHREAD_CANCEL_ASYNCHRONOUS : PTHREAD_CANCEL_DEFERRED);
+
+ /* Avoid doing unnecessary work. The atomic operation can
+ potentially be expensive if the memory has to be locked and
+ remote cache lines have to be invalidated. */
+ if (oldval == newval)
+ break;
+
+ /* Update the cancel handling word. This has to be done
+ atomically since other bits could be modified as well. */
+ int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval,
+ oldval);
+ if (__glibc_likely (curval == oldval))
+ {
+ if (CANCEL_ENABLED_AND_CANCELED_AND_ASYNCHRONOUS (newval))
+ {
+ THREAD_SETMEM (self, result, PTHREAD_CANCELED);
+ __do_cancel ();
+ }
+
+ break;
+ }
+
+ /* Prepare for the next round. */
+ oldval = curval;
+ }
+
+ return 0;
+}
+strong_alias (__pthread_setcanceltype, pthread_setcanceltype)