/* -*- mode: C++; c-file-style: "stroustrup"; c-basic-offset: 4; -*- * * This file is part of the UPPAAL DBM library. * * The UPPAAL DBM library 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 * 2 of the License, or (at your option) any later version. * * The UPPAAL DBM 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 General Public License for more details. * * You should have received a copy of the GNU General Public * License along with the UPPAAL DBM library; if not, write to the * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301 USA. */ // -*- mode: C++; c-file-style: "stroustrup"; c-basic-offset: 4; indent-tabs-mode: nil; -*- //////////////////////////////////////////////////////////////////// // // Filename : StreamHasher.h (hash) // // This file is a part of the UPPAAL toolkit. // Copyright (c) 1995 - 2003, Uppsala University and Aalborg University. // All right reserved. // // $Id: StreamHasher.h,v 1.3 2004/02/16 14:09:12 adavid Exp $ // /////////////////////////////////////////////////////////////////// #ifndef INCLUDE_HASH_STREAMHASHER_H #define INCLUDE_HASH_STREAMHASHER_H #include "base/inttypes.h" namespace hash { /** Hasher class to hash on generic streams of data. * WARNING: approx 5x slower than the hash_compute functions. */ class StreamHasher { public: /** Constructor. * @param initVal: initial value * for the hasher. */ StreamHasher(uint32_t initVal) : hashValue(initVal) {} /** Add a value to the hash. * @param value: value to hash. */ void addValue(uint32_t value) { hashValue = (hashValue ^ value) + ((hashValue << 26) + (hashValue >> 6)); } /** Wrapper for addValue. * @param value: int to wrap to uint. */ void addValue(int32_t value) { addValue((uint32_t)value); } /** Computes hash. * @return computed hash value. */ uint32_t hash() { return hashValue; } private: uint32_t hashValue; /**< current hash value */ }; } // namespace hash #endif // INCLUDE_HASH_STREAMHASHER_H