Tests for module 'random'.

[gnulib.git] / tests / test-random.c

diff --git a/tests/test-random.c b/tests/test-random.c
new file mode 100644 (file)
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+++ b/tests/test-random.c
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+/* Test random.
+   Copyright (C) 2008-2012 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+#include <stdlib.h>
+
+#include "signature.h"
+SIGNATURE_CHECK (srandom, void, (unsigned int));
+SIGNATURE_CHECK (initstate, char *, (unsigned int, char *, size_t));
+SIGNATURE_CHECK (setstate, char *, (char *));
+SIGNATURE_CHECK (random, long, (void));
+
+#include <time.h>
+
+#include "macros.h"
+
+int
+main ()
+{
+  char buf[128];
+  unsigned int i;
+  unsigned int n_big = 0;
+
+  initstate (time (NULL), buf, sizeof buf);
+  for (i = 0; i < 1000; i++)
+    {
+      long r = random ();
+      ASSERT (0 <= r);
+      if (RAND_MAX / 2 < r)
+        ++n_big;
+    }
+
+  /* Fail if none of the numbers were larger than RAND_MAX / 2.  */
+  return !n_big;
+}