cleanup: move rand_r compat code to tests

[urcu.git] / tests / common / compat-rand.h

diff --git a/tests/common/compat-rand.h b/tests/common/compat-rand.h
new file mode 100644 (file)
index 0000000..42fbb30
--- /dev/null
+++ b/tests/common/compat-rand.h
@@ -0,0 +1,49 @@
+// SPDX-FileCopyrightText: 1996 Ulrich Drepper <drepper@cygnus.com>
+// SPDX-FileCopyrightText: 2013 Pierre-Luc St-Charles <pierre-luc.st-charles@polymtl.ca>
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+
+#ifndef _COMPAT_RAND_H
+#define _COMPAT_RAND_H
+
+/*
+ * Userspace RCU library - rand/rand_r Compatibility Header
+ *
+ * Note: this file is only used to simplify the code required to
+ * use the 'rand_r(...)' system function across multiple platforms,
+ * which might not always be referenced the same way.
+ */
+
+#ifndef HAVE_RAND_R
+/*
+ * Reentrant random function from POSIX.1c.
+ * Copyright (C) 1996, 1999 Free Software Foundation, Inc.
+ * This file is part of the GNU C Library.
+ * Contributed by Ulrich Drepper <drepper@cygnus.com <mailto:drepper@cygnus.com>>, 1996.
+ */
+static inline int rand_r(unsigned int *seed)
+{
+       unsigned int next = *seed;
+       int result;
+
+       next *= 1103515245;
+       next += 12345;
+       result = (unsigned int) (next / 65536) % 2048;
+
+       next *= 1103515245;
+       next += 12345;
+       result <<= 10;
+       result ^= (unsigned int) (next / 65536) % 1024;
+
+       next *= 1103515245;
+       next += 12345;
+       result <<= 10;
+       result ^= (unsigned int) (next / 65536) % 1024;
+
+       *seed = next;
+
+       return result;
+}
+#endif /* HAVE_RAND_R */
+
+#endif /* _COMPAT_RAND_H */