src/stable/randomsystem.cpp


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#include "bu/randomsystem.h"
#include "bu/file.h"

Bu::RandomSystem::RandomSystem( Type eType ) :
    eType( eType ),
    pSrc( 0 )
{
    switch( eType )
    {
        case Bu::RandomSystem::Fast:
            pSrc = new Bu::File("/dev/urandom", Bu::File::Read );
            break;

        case Bu::RandomSystem::Good:
            pSrc = new Bu::File("/dev/random", Bu::File::Read );
            break;
    }
}

Bu::RandomSystem::~RandomSystem()
{
    delete pSrc;
}

void Bu::RandomSystem::seed( int32_t /*iSeed*/ )
{
    // Seed really has no effect here...
    // on linux, if we were root, we could write data to random/urandom to
    // perturb the data, but it's not necesarry
}

int32_t Bu::RandomSystem::rand()
{
    if( !pSrc )
        throw Bu::ExceptionBase("Not initialized");
    int32_t i;
    pSrc->read( &i, sizeof(int32_t) );
    return i;
}