submitted 1.2.0

Foundation/include/Poco/Random.h

@@ -0,0 +1,191 @@
+//
+// Random.h
+//
+// $Id: //poco/1.2/Foundation/include/Poco/Random.h#1 $
+//
+// Library: Foundation
+// Package: Crypt
+// Module:  Random
+//
+// Definition of class Random.
+//
+// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// Permission is hereby granted, free of charge, to any person or organization
+// obtaining a copy of the software and accompanying documentation covered by
+// this license (the "Software") to use, reproduce, display, distribute,
+// execute, and transmit the Software, and to prepare derivative works of the
+// Software, and to permit third-parties to whom the Software is furnished to
+// do so, all subject to the following:
+// 
+// The copyright notices in the Software and this entire statement, including
+// the above license grant, this restriction and the following disclaimer,
+// must be included in all copies of the Software, in whole or in part, and
+// all derivative works of the Software, unless such copies or derivative
+// works are solely in the form of machine-executable object code generated by
+// a source language processor.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
+// SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
+// FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
+// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+//
+//
+// Based on the FreeBSD random number generator.
+// src/lib/libc/stdlib/random.c,v 1.13 2000/01/27 23:06:49 jasone Exp
+//
+// Copyright (c) 1983, 1993
+// The Regents of the University of California.  All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions
+// are met:
+// 1. Redistributions of source code must retain the above copyright
+//    notice, this list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright
+//    notice, this list of conditions and the following disclaimer in the
+//    documentation and/or other materials provided with the distribution.
+// 3. All advertising materials mentioning features or use of this software
+//    must display the following acknowledgement:
+//    This product includes software developed by the University of
+//    California, Berkeley and its contributors.
+// 4. Neither the name of the University nor the names of its contributors
+//    may be used to endorse or promote products derived from this software
+//    without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+// OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+// SUCH DAMAGE.
+//
+
+
+#ifndef Foundation_Random_INCLUDED
+#define Foundation_Random_INCLUDED
+
+
+#include "Poco/Foundation.h"
+
+
+namespace Poco {
+
+
+class Foundation_API Random
+	/// A better random number generator.
+	/// Random implements a pseudo random number generator
+	/// (PRNG). The PRNG is a nonlinear additive
+	/// feedback random number generator using 256 bytes
+	/// of state information and a period of up to 2^69.
+{
+public:
+	enum Type
+	{
+		RND_STATE_0   =   8,  /// linear congruential
+		RND_STATE_32  =  32,  /// x**7 + x**3 + 1
+		RND_STATE_64  =  64,  /// x**15 + x + 1
+		RND_STATE_128 = 128,  /// x**31 + x**3 + 1
+		RND_STATE_256 = 256   /// x**63 + x + 1
+	};
+
+	Random(int stateSize = 256);
+		/// Creates and initializes the PRNG.
+		/// Specify either a state buffer size
+		/// (8 to 256 bytes) or one of the Type values.
+
+	~Random();
+		/// Destroys the PRNG.
+
+	void seed(UInt32 seed);
+		/// Seeds the pseudo random generator with the given seed.
+
+	void seed();
+		/// Seeds the pseudo random generator with a random seed
+		/// obtained from a RandomInputStream.
+
+	UInt32 next();
+		/// Returns the next 31-bit pseudo random number.
+
+	UInt32 next(UInt32 n);
+		/// Returns the next 31-bit pseudo random number modulo n.
+	
+	char nextChar();
+		/// Returns the next pseudo random character.
+	
+	bool nextBool();
+		/// Returns the next boolean pseudo random value.
+		
+	float nextFloat();
+		/// Returns the next float pseudo random number between 0.0 and 1.0.
+		
+	double nextDouble();
+		/// Returns the next double pseudo random number between 0.0 and 1.0.
+
+protected:
+	void initState(UInt32 seed, char* arg_state, Int32 n);
+	static UInt32 goodRand(Int32 x);
+
+private:
+	enum
+	{
+		MAX_TYPES = 5,
+		NSHUFF    = 50
+	};
+
+	UInt32* _fptr;
+	UInt32* _rptr;
+	UInt32* _state;
+	int     _randType;
+	int     _randDeg;
+	int     _randSep;
+	UInt32* _endPtr;
+	char*  _pBuffer;
+};
+
+
+//
+// inlines
+//
+inline UInt32 Random::next(UInt32 n)
+{
+	return next() % n;
+}
+
+
+inline char Random::nextChar()
+{
+	return char((next() >> 3) & 0xFF);
+}
+
+
+inline bool Random::nextBool()
+{
+	return (next() & 0x1000) != 0;
+}
+
+	
+inline float Random::nextFloat()
+{
+	return float(next()) / 0x7FFFFFFF;
+}
+
+	
+inline double Random::nextDouble()
+{
+	return double(next()) / 0x7FFFFFFF;
+}
+
+
+} // namespace Poco
+
+
+#endif // Foundation_Random_INCLUDED