lbrycrd/src/random.h
isle2983 27765b6403 Increment MIT Licence copyright header year on files modified in 2016
Edited via:

$ contrib/devtools/copyright_header.py update .
2016-12-31 11:01:21 -07:00

49 lines
1.3 KiB
C++

// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2016 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef BITCOIN_RANDOM_H
#define BITCOIN_RANDOM_H
#include "uint256.h"
#include <stdint.h>
/* Seed OpenSSL PRNG with additional entropy data */
void RandAddSeed();
/**
* Functions to gather random data via the OpenSSL PRNG
*/
void GetRandBytes(unsigned char* buf, int num);
uint64_t GetRand(uint64_t nMax);
int GetRandInt(int nMax);
uint256 GetRandHash();
/**
* Function to gather random data from multiple sources, failing whenever any
* of those source fail to provide a result.
*/
void GetStrongRandBytes(unsigned char* buf, int num);
/**
* Fast randomness source. This is seeded once with secure random data, but
* is completely deterministic and insecure after that.
* This class is not thread-safe.
*/
class FastRandomContext {
public:
explicit FastRandomContext(bool fDeterministic=false);
uint32_t rand32() {
Rz = 36969 * (Rz & 65535) + (Rz >> 16);
Rw = 18000 * (Rw & 65535) + (Rw >> 16);
return (Rw << 16) + Rz;
}
uint32_t Rz;
uint32_t Rw;
};
#endif // BITCOIN_RANDOM_H