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+/* futex operations for glibc-internal use. Stub version; do not include
+ this file directly.
+ Copyright (C) 2014-2020 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ 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
+ <https://www.gnu.org/licenses/>. */
+
+#ifndef STUB_FUTEX_INTERNAL_H
+#define STUB_FUTEX_INTERNAL_H
+
+#include <pthread.h>
+
+/* Returns EINVAL if PSHARED is neither PTHREAD_PROCESS_PRIVATE nor
+ PTHREAD_PROCESS_SHARED; otherwise, returns 0 if PSHARED is supported, and
+ ENOTSUP if not. */
+static __always_inline int
+futex_supports_pshared (int pshared)
+{
+ if (__glibc_likely (pshared == PTHREAD_PROCESS_PRIVATE))
+ return 0;
+ else if (pshared == PTHREAD_PROCESS_SHARED)
+ return 0;
+ else
+ return EINVAL;
+}
+
+#endif /* futex-internal.h */