// random.cpp
/* Copyright 2012 10gen Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see .
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the GNU Affero General Public License in all respects
* for all of the code used other than as permitted herein. If you modify
* file(s) with this exception, you may extend this exception to your
* version of the file(s), but you are not obligated to do so. If you do not
* wish to do so, delete this exception statement from your version. If you
* delete this exception statement from all source files in the program,
* then also delete it in the license file.
*/
#include "mongo/platform/random.h"
#include
#include
#ifndef _WIN32
#include
#endif
#define _CRT_RAND_S
#include
#include
#include
#include "mongo/platform/basic.h"
namespace mongo {
// ---- PseudoRandom -----
int32_t PseudoRandom::nextInt32() {
int32_t t = _x ^ (_x << 11);
_x = _y;
_y = _z;
_z = _w;
return _w = _w ^ (_w >> 19) ^ (t ^ (t >> 8));
}
namespace {
const int32_t default_y = 362436069;
const int32_t default_z = 521288629;
const int32_t default_w = 88675123;
}
PseudoRandom::PseudoRandom( int32_t seed ) {
_x = seed;
_y = default_y;
_z = default_z;
_w = default_w;
}
PseudoRandom::PseudoRandom( uint32_t seed ) {
_x = static_cast(seed);
_y = default_y;
_z = default_z;
_w = default_w;
}
PseudoRandom::PseudoRandom( int64_t seed ) {
int32_t high = seed >> 32;
int32_t low = seed & 0xFFFFFFFF;
_x = high ^ low;
_y = default_y;
_z = default_z;
_w = default_w;
}
int64_t PseudoRandom::nextInt64() {
int64_t a = nextInt32();
int64_t b = nextInt32();
return ( a << 32 ) | b;
}
// --- SecureRandom ----
SecureRandom::~SecureRandom() {
}
#ifdef _WIN32
class WinSecureRandom : public SecureRandom {
virtual ~WinSecureRandom(){}
int64_t nextInt64() {
uint32_t a, b;
if ( rand_s(&a) ) {
abort();
}
if ( rand_s(&b) ) {
abort();
}
return ( static_cast(a) << 32 ) | b;
}
};
SecureRandom* SecureRandom::create() {
return new WinSecureRandom();
}
#elif defined(__linux__) || defined(__sunos__) || defined(__APPLE__)
class InputStreamSecureRandom : public SecureRandom {
public:
InputStreamSecureRandom( const char* fn ) {
_in = new std::ifstream( fn, std::ios::binary | std::ios::in );
if ( !_in->is_open() ) {
std::cerr << "can't open " << fn << " " << strerror(errno) << std::endl;
abort();
}
}
~InputStreamSecureRandom() {
delete _in;
}
int64_t nextInt64() {
int64_t r;
_in->read( reinterpret_cast( &r ), sizeof(r) );
if ( _in->fail() ) {
abort();
}
return r;
}
private:
std::ifstream* _in;
};
SecureRandom* SecureRandom::create() {
return new InputStreamSecureRandom( "/dev/urandom" );
}
#else
class SRandSecureRandom : public SecureRandom {
public:
SRandSecureRandom() {
srandomdev();
}
int64_t nextInt64() {
long a, b;
a = random();
b = random();
return ( static_cast(a) << 32 ) | b;
}
};
SecureRandom* SecureRandom::create() {
return new SRandSecureRandom();
}
#endif
}