genericopenlibs/openenvcore/libc/src/random.c
author Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
Wed, 13 Oct 2010 16:27:53 +0300
branchRCL_3
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parent 0 e4d67989cc36
permissions -rw-r--r--
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/*
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 * Copyright (c) 1983, 1993
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 *	The Regents of the University of California.  All rights reserved.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 4. Neither the name of the University nor the names of its contributors
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 *    may be used to endorse or promote products derived from this software
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 *    without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 * © Portions copyright (c) 2006 Nokia Corporation.  All rights reserved.
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 */
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#if defined(LIBC_SCCS) && !defined(lint)
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static char sccsid[] = "@(#)random.c	8.2 (Berkeley) 5/19/95";
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#endif /* LIBC_SCCS and not lint */
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD: src/lib/libc/stdlib/random.c,v 1.24 2004/01/20 03:02:18 das Exp $");
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#include <sys/time.h>          /* for srandomdev() */
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#include <fcntl.h>             /* for srandomdev() */
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#include <stdint.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>            /* for srandomdev() */
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/*
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 * random.c:
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 *
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 * An improved random number generation package.  In addition to the standard
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 * rand()/srand() like interface, this package also has a special state info
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 * interface.  The initstate() routine is called with a seed, an array of
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 * bytes, and a count of how many bytes are being passed in; this array is
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 * then initialized to contain information for random number generation with
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 * that much state information.  Good sizes for the amount of state
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 * information are 32, 64, 128, and 256 bytes.  The state can be switched by
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 * calling the setstate() routine with the same array as was initiallized
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 * with initstate().  By default, the package runs with 128 bytes of state
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 * information and generates far better random numbers than a linear
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 * congruential generator.  If the amount of state information is less than
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 * 32 bytes, a simple linear congruential R.N.G. is used.
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 *
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 * Internally, the state information is treated as an array of uint32_t's; the
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 * zeroeth element of the array is the type of R.N.G. being used (small
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 * integer); the remainder of the array is the state information for the
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 * R.N.G.  Thus, 32 bytes of state information will give 7 ints worth of
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 * state information, which will allow a degree seven polynomial.  (Note:
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 * the zeroeth word of state information also has some other information
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 * stored in it -- see setstate() for details).
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 *
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 * The random number generation technique is a linear feedback shift register
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 * approach, employing trinomials (since there are fewer terms to sum up that
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 * way).  In this approach, the least significant bit of all the numbers in
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 * the state table will act as a linear feedback shift register, and will
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 * have period 2^deg - 1 (where deg is the degree of the polynomial being
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 * used, assuming that the polynomial is irreducible and primitive).  The
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 * higher order bits will have longer periods, since their values are also
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 * influenced by pseudo-random carries out of the lower bits.  The total
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 * period of the generator is approximately deg*(2**deg - 1); thus doubling
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 * the amount of state information has a vast influence on the period of the
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 * generator.  Note: the deg*(2**deg - 1) is an approximation only good for
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 * large deg, when the period of the shift is the dominant factor.
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 * With deg equal to seven, the period is actually much longer than the
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 * 7*(2**7 - 1) predicted by this formula.
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 *
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 * Modified 28 December 1994 by Jacob S. Rosenberg.
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 * The following changes have been made:
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 * All references to the type u_int have been changed to unsigned long.
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 * All references to type int have been changed to type long.  Other
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 * cleanups have been made as well.  A warning for both initstate and
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 * setstate has been inserted to the effect that on Sparc platforms
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 * the 'arg_state' variable must be forced to begin on word boundaries.
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 * This can be easily done by casting a long integer array to char *.
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 * The overall logic has been left STRICTLY alone.  This software was
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 * tested on both a VAX and Sun SpacsStation with exactly the same
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 * results.  The new version and the original give IDENTICAL results.
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 * The new version is somewhat faster than the original.  As the
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 * documentation says:  "By default, the package runs with 128 bytes of
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 * state information and generates far better random numbers than a linear
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 * congruential generator.  If the amount of state information is less than
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 * 32 bytes, a simple linear congruential R.N.G. is used."  For a buffer of
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 * 128 bytes, this new version runs about 19 percent faster and for a 16
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 * byte buffer it is about 5 percent faster.
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 */
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/*
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 * For each of the currently supported random number generators, we have a
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 * break value on the amount of state information (you need at least this
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 * many bytes of state info to support this random number generator), a degree
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 * for the polynomial (actually a trinomial) that the R.N.G. is based on, and
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 * the separation between the two lower order coefficients of the trinomial.
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 */
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#define	TYPE_0		0		/* linear congruential */
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#define	BREAK_0		8
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#define	DEG_0		0
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#define	SEP_0		0
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#define	TYPE_1		1		/* x**7 + x**3 + 1 */
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#define	BREAK_1		32
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#define	DEG_1		7
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#define	SEP_1		3
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#define	TYPE_2		2		/* x**15 + x + 1 */
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#define	BREAK_2		64
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#define	DEG_2		15
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#define	SEP_2		1
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#define	TYPE_3		3		/* x**31 + x**3 + 1 */
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#define	BREAK_3		128
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#define	DEG_3		31
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#define	SEP_3		3
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#define	TYPE_4		4		/* x**63 + x + 1 */
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#define	BREAK_4		256
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#define	DEG_4		63
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#define	SEP_4		1
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/*
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 * Array versions of the above information to make code run faster --
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 * relies on fact that TYPE_i == i.
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 */
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#define	MAX_TYPES	5		/* max number of types above */
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#ifdef  USE_WEAK_SEEDING
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#define NSHUFF 0
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#else   /* !USE_WEAK_SEEDING */
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#define NSHUFF 50       /* to drop some "seed -> 1st value" linearity */
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#endif  /* !USE_WEAK_SEEDING */
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static const int degrees[MAX_TYPES] =	{ DEG_0, DEG_1, DEG_2, DEG_3, DEG_4 };
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static const int seps [MAX_TYPES] =	{ SEP_0, SEP_1, SEP_2, SEP_3, SEP_4 };
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/*
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 * Initially, everything is set up as if from:
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 *
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 *	initstate(1, randtbl, 128);
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 *
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 * Note that this initialization takes advantage of the fact that srandom()
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 * advances the front and rear pointers 10*rand_deg times, and hence the
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 * rear pointer which starts at 0 will also end up at zero; thus the zeroeth
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 * element of the state information, which contains info about the current
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 * position of the rear pointer is just
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 *
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 *	MAX_TYPES * (rptr - state) + TYPE_3 == TYPE_3.
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 */
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   163
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static uint32_t randtbl[DEG_3 + 1] = {
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	TYPE_3,
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#ifdef  USE_WEAK_SEEDING
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/* Historic implementation compatibility */
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/* The random sequences do not vary much with the seed */
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	0x9a319039, 0x32d9c024, 0x9b663182, 0x5da1f342, 0xde3b81e0, 0xdf0a6fb5,
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	0xf103bc02, 0x48f340fb, 0x7449e56b, 0xbeb1dbb0, 0xab5c5918, 0x946554fd,
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	0x8c2e680f, 0xeb3d799f, 0xb11ee0b7, 0x2d436b86, 0xda672e2a, 0x1588ca88,
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	0xe369735d, 0x904f35f7, 0xd7158fd6, 0x6fa6f051, 0x616e6b96, 0xac94efdc,
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   173
	0x36413f93, 0xc622c298, 0xf5a42ab8, 0x8a88d77b, 0xf5ad9d0e, 0x8999220b,
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	0x27fb47b9,
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#else   /* !USE_WEAK_SEEDING */
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	0x991539b1, 0x16a5bce3, 0x6774a4cd, 0x3e01511e, 0x4e508aaa, 0x61048c05,
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	0xf5500617, 0x846b7115, 0x6a19892c, 0x896a97af, 0xdb48f936, 0x14898454,
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   178
	0x37ffd106, 0xb58bff9c, 0x59e17104, 0xcf918a49, 0x09378c83, 0x52c7a471,
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   179
	0x8d293ea9, 0x1f4fc301, 0xc3db71be, 0x39b44e1c, 0xf8a44ef9, 0x4c8b80b1,
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	0x19edc328, 0x87bf4bdd, 0xc9b240e5, 0xe9ee4b1b, 0x4382aee7, 0x535b6b41,
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	0xf3bec5da
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#endif  /* !USE_WEAK_SEEDING */
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};
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/*
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 * fptr and rptr are two pointers into the state info, a front and a rear
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 * pointer.  These two pointers are always rand_sep places aparts, as they
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 * cycle cyclically through the state information.  (Yes, this does mean we
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 * could get away with just one pointer, but the code for random() is more
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 * efficient this way).  The pointers are left positioned as they would be
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 * from the call
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 *
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 *	initstate(1, randtbl, 128);
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 *
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 * (The position of the rear pointer, rptr, is really 0 (as explained above
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 * in the initialization of randtbl) because the state table pointer is set
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 * to point to randtbl[1] (as explained below).
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 */
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static uint32_t *fptr = &randtbl[SEP_3 + 1];
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static uint32_t *rptr = &randtbl[1];
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/*
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 * The following things are the pointer to the state information table, the
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 * type of the current generator, the degree of the current polynomial being
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 * used, and the separation between the two pointers.  Note that for efficiency
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 * of random(), we remember the first location of the state information, not
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 * the zeroeth.  Hence it is valid to access state[-1], which is used to
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 * store the type of the R.N.G.  Also, we remember the last location, since
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 * this is more efficient than indexing every time to find the address of
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 * the last element to see if the front and rear pointers have wrapped.
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 */
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static uint32_t *state = &randtbl[1];
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static int rand_type = TYPE_3;
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static int rand_deg = DEG_3;
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static int rand_sep = SEP_3;
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static uint32_t *end_ptr = &randtbl[DEG_3 + 1];
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static inline uint32_t good_rand(int32_t);
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static inline uint32_t good_rand (x)
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	int32_t x;
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{
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#ifdef  USE_WEAK_SEEDING
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/*
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 * Historic implementation compatibility.
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 * The random sequences do not vary much with the seed,
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 * even with overflowing.
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 */
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	return (1103515245 * x + 12345);
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#else   /* !USE_WEAK_SEEDING */
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/*
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 * Compute x = (7^5 * x) mod (2^31 - 1)
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 * wihout overflowing 31 bits:
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 *      (2^31 - 1) = 127773 * (7^5) + 2836
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 * From "Random number generators: good ones are hard to find",
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 * Park and Miller, Communications of the ACM, vol. 31, no. 10,
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 * October 1988, p. 1195.
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 */
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	int32_t hi, lo;
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	/* Can't be initialized with 0, so use another value. */
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	if (x == 0)
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		x = 123459876;
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	hi = x / 127773;
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	lo = x % 127773;
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	x = 16807 * lo - 2836 * hi;
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	if (x < 0)
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		x += 0x7fffffff;
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	return (x);
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#endif  /* !USE_WEAK_SEEDING */
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}
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/*
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 * srandom:
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 *
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 * Initialize the random number generator based on the given seed.  If the
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 * type is the trivial no-state-information type, just remember the seed.
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 * Otherwise, initializes state[] based on the given "seed" via a linear
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 * congruential generator.  Then, the pointers are set to known locations
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 * that are exactly rand_sep places apart.  Lastly, it cycles the state
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 * information a given number of times to get rid of any initial dependencies
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 * introduced by the L.C.R.N.G.  Note that the initialization of randtbl[]
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 * for default usage relies on values produced by this routine.
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 */
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EXPORT_C
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void
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srandom(x)
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	unsigned long x;
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{
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	int i, lim;
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	state[0] = (uint32_t)x;
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	if (rand_type == TYPE_0)
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		lim = NSHUFF;
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	else {
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		for (i = 1; i < rand_deg; i++)
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			state[i] = good_rand(state[i - 1]);
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		fptr = &state[rand_sep];
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		rptr = &state[0];
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		lim = 10 * rand_deg;
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	}
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	for (i = 0; i < lim; i++)
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		(void)random();
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}
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#ifdef __SYMBIAN_COMPILE_UNUSED__
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/*
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 * srandomdev:
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 *
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 * Many programs choose the seed value in a totally predictable manner.
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 * This often causes problems.  We seed the generator using the much more
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 * secure random(4) interface.  Note that this particular seeding
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   293
 * procedure can generate states which are impossible to reproduce by
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 * calling srandom() with any value, since the succeeding terms in the
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 * state buffer are no longer derived from the LC algorithm applied to
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 * a fixed seed.
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 */
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void
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srandomdev()
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{
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	int fd, done;
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	size_t len;
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   303
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	if (rand_type == TYPE_0)
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		len = sizeof state[0];
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	else
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		len = rand_deg * sizeof state[0];
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   308
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	done = 0;
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	fd = open("/dev/random", O_RDONLY, 0);
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	if (fd >= 0) {
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		if (read(fd, (void *) state, len) == (ssize_t) len)
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			done = 1;
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		close(fd);
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	}
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   316
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   317
	if (!done) {
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		struct timeval tv;
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		unsigned long junk = 0;
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   320
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   321
		gettimeofday(&tv, NULL);
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		srandom((getpid() << 16) ^ tv.tv_sec ^ tv.tv_usec ^ junk);
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		return;
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   324
	}
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   325
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   326
	if (rand_type != TYPE_0) {
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diff changeset
   327
		fptr = &state[rand_sep];
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Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   328
		rptr = &state[0];
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   329
	}
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   330
}
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   331
#endif
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   332
/*
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   333
 * initstate:
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   334
 *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   335
 * Initialize the state information in the given array of n bytes for future
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   336
 * random number generation.  Based on the number of bytes we are given, and
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   337
 * the break values for the different R.N.G.'s, we choose the best (largest)
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   338
 * one we can and set things up for it.  srandom() is then called to
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   339
 * initialize the state information.
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   340
 *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   341
 * Note that on return from srandom(), we set state[-1] to be the type
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   342
 * multiplexed with the current value of the rear pointer; this is so
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   343
 * successive calls to initstate() won't lose this information and will be
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   344
 * able to restart with setstate().
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   345
 *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   346
 * Note: the first thing we do is save the current state, if any, just like
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   347
 * setstate() so that it doesn't matter when initstate is called.
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   348
 *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   349
 * Returns a pointer to the old state.
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   350
 *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   351
 * Note: The Sparc platform requires that arg_state begin on an int
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   352
 * word boundary; otherwise a bus error will occur. Even so, lint will
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   353
 * complain about mis-alignment, but you should disregard these messages.
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   354
 */
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   355
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   356
EXPORT_C
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   357
char *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   358
initstate(seed, arg_state, n)
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   359
	unsigned long seed;		/* seed for R.N.G. */
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   360
	char *arg_state;		/* pointer to state array */
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   361
	long n;				/* # bytes of state info */
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   362
{
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   363
	char *ostate = (char *)(&state[-1]);
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   364
	uint32_t *int_arg_state = (uint32_t *)arg_state;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   365
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   366
	if (rand_type == TYPE_0)
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   367
		state[-1] = rand_type;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   368
	else
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   369
		state[-1] = MAX_TYPES * (rptr - state) + rand_type;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   370
	if (n < BREAK_0) {
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   371
		(void)fprintf(stderr,
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   372
		    "random: not enough state (%ld bytes); ignored.\n", n);
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   373
		return(0);
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   374
	}
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   375
	if (n < BREAK_1) {
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   376
		rand_type = TYPE_0;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   377
		rand_deg = DEG_0;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   378
		rand_sep = SEP_0;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   379
	} else if (n < BREAK_2) {
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   380
		rand_type = TYPE_1;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   381
		rand_deg = DEG_1;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   382
		rand_sep = SEP_1;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   383
	} else if (n < BREAK_3) {
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   384
		rand_type = TYPE_2;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   385
		rand_deg = DEG_2;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   386
		rand_sep = SEP_2;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   387
	} else if (n < BREAK_4) {
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   388
		rand_type = TYPE_3;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   389
		rand_deg = DEG_3;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   390
		rand_sep = SEP_3;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   391
	} else {
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   392
		rand_type = TYPE_4;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   393
		rand_deg = DEG_4;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   394
		rand_sep = SEP_4;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   395
	}
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   396
	state = int_arg_state + 1; /* first location */
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   397
	end_ptr = &state[rand_deg];	/* must set end_ptr before srandom */
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   398
	srandom(seed);
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   399
	if (rand_type == TYPE_0)
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   400
		int_arg_state[0] = rand_type;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   401
	else
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   402
		int_arg_state[0] = MAX_TYPES * (rptr - state) + rand_type;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   403
	return(ostate);
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   404
}
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   405
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   406
/*
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   407
 * setstate:
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   408
 *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   409
 * Restore the state from the given state array.
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   410
 *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   411
 * Note: it is important that we also remember the locations of the pointers
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   412
 * in the current state information, and restore the locations of the pointers
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   413
 * from the old state information.  This is done by multiplexing the pointer
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   414
 * location into the zeroeth word of the state information.
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   415
 *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   416
 * Note that due to the order in which things are done, it is OK to call
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   417
 * setstate() with the same state as the current state.
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   418
 *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   419
 * Returns a pointer to the old state information.
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   420
 *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   421
 * Note: The Sparc platform requires that arg_state begin on an int
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   422
 * word boundary; otherwise a bus error will occur. Even so, lint will
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   423
 * complain about mis-alignment, but you should disregard these messages.
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   424
 */
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   425
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   426
EXPORT_C
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   427
char *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   428
setstate(arg_state)
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   429
	char *arg_state;		/* pointer to state array */
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   430
{
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   431
	uint32_t *new_state = (uint32_t *)arg_state;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   432
	uint32_t type = new_state[0] % MAX_TYPES;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   433
	uint32_t rear = new_state[0] / MAX_TYPES;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   434
	char *ostate = (char *)(&state[-1]);
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   435
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   436
	if (rand_type == TYPE_0)
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   437
		state[-1] = rand_type;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   438
	else
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   439
		state[-1] = MAX_TYPES * (rptr - state) + rand_type;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   440
	switch(type) {
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   441
	case TYPE_0:
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   442
	case TYPE_1:
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   443
	case TYPE_2:
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   444
	case TYPE_3:
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   445
	case TYPE_4:
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   446
		rand_type = type;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   447
		rand_deg = degrees[type];
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   448
		rand_sep = seps[type];
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   449
		break;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   450
	default:
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   451
		(void)fprintf(stderr,
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   452
		    "random: state info corrupted; not changed.\n");
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   453
	}
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   454
	state = new_state + 1;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   455
	if (rand_type != TYPE_0) {
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   456
		rptr = &state[rear];
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   457
		fptr = &state[(rear + rand_sep) % rand_deg];
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   458
	}
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   459
	end_ptr = &state[rand_deg];		/* set end_ptr too */
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   460
	return(ostate);
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   461
}
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   462
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   463
/*
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   464
 * random:
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   465
 *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   466
 * If we are using the trivial TYPE_0 R.N.G., just do the old linear
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   467
 * congruential bit.  Otherwise, we do our fancy trinomial stuff, which is
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   468
 * the same in all the other cases due to all the global variables that have
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   469
 * been set up.  The basic operation is to add the number at the rear pointer
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   470
 * into the one at the front pointer.  Then both pointers are advanced to
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   471
 * the next location cyclically in the table.  The value returned is the sum
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   472
 * generated, reduced to 31 bits by throwing away the "least random" low bit.
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   473
 *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   474
 * Note: the code takes advantage of the fact that both the front and
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   475
 * rear pointers can't wrap on the same call by not testing the rear
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   476
 * pointer if the front one has wrapped.
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   477
 *
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   478
 * Returns a 31-bit random number.
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   479
 */
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   480
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   481
EXPORT_C
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   482
long
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   483
random()
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   484
{
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   485
	uint32_t i;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   486
	uint32_t *f, *r;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   487
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   488
	if (rand_type == TYPE_0) {
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   489
		i = state[0];
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   490
		state[0] = i = (good_rand(i)) & 0x7fffffff;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   491
	} else {
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   492
		/*
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   493
		 * Use local variables rather than static variables for speed.
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   494
		 */
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   495
		f = fptr; r = rptr;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   496
		*f += *r;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   497
		i = (*f >> 1) & 0x7fffffff;	/* chucking least random bit */
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   498
		if (++f >= end_ptr) {
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   499
			f = state;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   500
			++r;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   501
		}
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   502
		else if (++r >= end_ptr) {
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   503
			r = state;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   504
		}
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   505
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   506
		fptr = f; rptr = r;
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   507
	}
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   508
	return((long)i);
e4d67989cc36 Revision: 201002
Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
parents:
diff changeset
   509
}