JezK
Edit File: randomkit.h
/* Random kit 1.3 */ /* * Copyright (c) 2003-2005, Jean-Sebastien Roy (js@jeannot.org) * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * 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 AND NONINFRINGEMENT. * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ /* @(#) $Jeannot: randomkit.h,v 1.24 2005/07/21 22:14:09 js Exp $ */ /* * Typical use: * * { * rk_state state; * unsigned long seed = 1, random_value; * * rk_seed(seed, &state); // Initialize the RNG * ... * random_value = rk_random(&state); // Generate random values in [0..RK_MAX] * } * * Instead of rk_seed, you can use rk_randomseed which will get a random seed * from /dev/urandom (or the clock, if /dev/urandom is unavailable): * * { * rk_state state; * unsigned long random_value; * * rk_randomseed(&state); // Initialize the RNG with a random seed * ... * random_value = rk_random(&state); // Generate random values in [0..RK_MAX] * } */ /* * Useful macro: * RK_DEV_RANDOM: the device used for random seeding. * defaults to "/dev/urandom" */ #include <stddef.h> #ifndef _RANDOMKIT_ #define _RANDOMKIT_ #define RK_STATE_LEN 624 typedef struct rk_state_ { unsigned long key[RK_STATE_LEN]; int pos; int has_gauss; /* !=0: gauss contains a gaussian deviate */ double gauss; /* The rk_state structure has been extended to store the following * information for the binomial generator. If the input values of n or p * are different than nsave and psave, then the other parameters will be * recomputed. RTK 2005-09-02 */ int has_binomial; /* !=0: following parameters initialized for binomial */ double psave; long nsave; double r; double q; double fm; long m; double p1; double xm; double xl; double xr; double c; double laml; double lamr; double p2; double p3; double p4; } rk_state; typedef enum { RK_NOERR = 0, /* no error */ RK_ENODEV = 1, /* no RK_DEV_RANDOM device */ RK_ERR_MAX = 2 } rk_error; /* error strings */ extern char *rk_strerror[RK_ERR_MAX]; /* Maximum generated random value */ #define RK_MAX 0xFFFFFFFFUL #ifdef __cplusplus extern "C" { #endif /* * Initialize the RNG state using the given seed. */ extern void rk_seed(unsigned long seed, rk_state *state); /* * Initialize the RNG state using a random seed. * Uses /dev/random or, when unavailable, the clock (see randomkit.c). * Returns RK_NOERR when no errors occurs. * Returns RK_ENODEV when the use of RK_DEV_RANDOM failed (for example because * there is no such device). In this case, the RNG was initialized using the * clock. */ extern rk_error rk_randomseed(rk_state *state); /* * Returns a random unsigned long between 0 and RK_MAX inclusive */ extern unsigned long rk_random(rk_state *state); /* * Returns a random long between 0 and LONG_MAX inclusive */ extern long rk_long(rk_state *state); /* * Returns a random unsigned long between 0 and ULONG_MAX inclusive */ extern unsigned long rk_ulong(rk_state *state); /* * Returns a random unsigned long between 0 and max inclusive. */ extern unsigned long rk_interval(unsigned long max, rk_state *state); /* * Returns a random double between 0.0 and 1.0, 1.0 excluded. */ extern double rk_double(rk_state *state); /* * fill the buffer with size random bytes */ extern void rk_fill(void *buffer, size_t size, rk_state *state); /* * fill the buffer with randombytes from the random device * Returns RK_ENODEV if the device is unavailable, or RK_NOERR if it is * On Unix, if strong is defined, RK_DEV_RANDOM is used. If not, RK_DEV_URANDOM * is used instead. This parameter has no effect on Windows. * Warning: on most unixes RK_DEV_RANDOM will wait for enough entropy to answer * which can take a very long time on quiet systems. */ extern rk_error rk_devfill(void *buffer, size_t size, int strong); /* * fill the buffer using rk_devfill if the random device is available and using * rk_fill if is is not * parameters have the same meaning as rk_fill and rk_devfill * Returns RK_ENODEV if the device is unavailable, or RK_NOERR if it is */ extern rk_error rk_altfill(void *buffer, size_t size, int strong, rk_state *state); /* * return a random gaussian deviate with variance unity and zero mean. */ extern double rk_gauss(rk_state *state); #ifdef __cplusplus } #endif #endif /* _RANDOMKIT_ */