/*
* Copyright (c) 2008-2012 Zmanda, Inc. All Rights Reserved.
* Copyright (c) 2013-2016 Carbonite, Inc. All Rights Reserved.
*
* This program 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.
*
* This program 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 this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Contact information: Carbonite Inc., 756 N Pastoria Ave
* Sunnyvale, CA 94086, USA, or: http://www.zmanda.com
*/
#ifndef SIMPLEPRNG_H
#define SIMPLEPRNG_H
#include "amanda.h"
/* A very simple, thread-safe PRNG. This is intended for use in generating
* reproducable bytestreams for testing purposes. It is *not*
* cryptographically secure! */
typedef struct {
guint32 val;
guint64 count;
} simpleprng_state_t;
/* Initialize and seed the PRNG
*
* @param state: pointer to PRNG state
* @param seed: initial value
*/
void simpleprng_seed(
simpleprng_state_t *state,
guint32 seed);
/* Get a seed that will reproduce the PRNG's current state
*
* @param state: pointer to PRNG state
* @returns: seed;
*/
guint32 simpleprng_get_seed(
simpleprng_state_t *state);
/* Get a random guint32
*
* @param state: pointer to PRNG state
* @returns: random integer
*/
guint32 simpleprng_rand(
simpleprng_state_t *state);
/* Get a random byte
*
* @param state: pointer to PRNG state
* @returns: random integer
*/
/* use the high-order bytes, as they're "more random" */
#define simpleprng_rand_byte(state) \
((guint8)(simpleprng_rand((state)) >> 24))
/* Fill the given buffer with a sequence of bytes
*
* @param state: pointer to PRNG state
* @param buf: buffer to fill
* @param len: number of bytes to write
*/
void simpleprng_fill_buffer(
simpleprng_state_t *state,
gpointer buf,
size_t len);
/* Verify that a buffer matches the values from the PRNG.
*
* @param state: pointer to PRNG state
* @param buf: buffer to verify
* @param len: number of bytes to verify
* @returns: true if all bytes match
*/
gboolean simpleprng_verify_buffer(
simpleprng_state_t *state,
gpointer buf,
size_t len);
#endif /* SIMPLEPRNG_H */