mongodb/util/background.cpp

/**
*    Copyright (C) 2008 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 <http://www.gnu.org/licenses/>.
*/

#include "stdafx.h"
#include "goodies.h"
#include "background.h"

namespace mongo {

    BackgroundJob *BackgroundJob::grab = 0;
    boost::mutex BackgroundJob::mutex;

    /* static */
    void BackgroundJob::thr() {
        assert( grab );
        BackgroundJob *us = grab;
        assert( us->state == NotStarted );
        us->state = Running;
        grab = 0;
        us->run();
        us->state = Done;
        if ( us->deleteSelf )
            delete us;
    }

    BackgroundJob& BackgroundJob::go() {
        boostlock bl(mutex);
        assert( grab == 0 );
        grab = this;
        boost::thread t(thr);
        while ( grab )
            sleepmillis(2);
        return *this;
    }

    bool BackgroundJob::wait(int msMax) {
        assert( state != NotStarted );
        int ms = 1;
        unsigned long long start = jsTime();
        while ( state != Done ) {
            sleepmillis(ms);
            if ( ms < 1000 )
                ms = ms * 2;
            if ( msMax && ( int( jsTime() - start ) > msMax) )
                return false;
        }
        return true;
    }

} // namespace mongo