Include RE2 library

third_party/re2/util/random.h

+// Copyright 2005-2009 The RE2 Authors.  All Rights Reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Modified from Google perftools's tcmalloc_unittest.cc.
+
+#ifndef RE2_UTIL_RANDOM_H__
+#define RE2_UTIL_RANDOM_H__
+
+#include "util/util.h"
+
+namespace re2 {
+
+// ACM minimal standard random number generator.  (re-entrant.)
+class ACMRandom {
+ public:
+  ACMRandom(int32 seed) : seed_(seed) {}
+  int32 Next();
+  int32 Uniform(int32);
+
+  void Reset(int32 seed) { seed_ = seed; }
+
+ private:
+  int32 seed_;
+};
+
+}  // namespace re2
+
+#endif  // RE2_UTIL_RANDOM_H__