jni/commoncpp2-1.8.1-android/src/runlist.cpp

// Copyright (C) 2004-2005 Open Source Telecom Corporation.
// Copyright (C) 2006-2010 David Sugar, Tycho Softworks.
//
// 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.
//
// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.
//
// This exception applies only to the code released under the name GNU
// Common C++.  If you copy code from other releases into a copy of GNU
// Common C++, as the General Public License permits, the exception does
// not apply to the code that you add in this way.  To avoid misleading
// anyone as to the status of such modified files, you must delete
// this exception notice from them.
//
// If you write modifications of your own for GNU Common C++, it is your choice
// whether to permit this exception to apply to your modifications.
// If you do not wish that, delete this exception notice.
//

#include <cc++/config.h>
#include <cc++/export.h>
#include <cc++/thread.h>
#include <cc++/misc.h>
#include "private.h"

#ifdef  CCXX_NAMESPACES
namespace ost {
#endif

Runlist::Runlist(unsigned count) :
Mutex()
{
    first = last = NULL;
    limit = count;
    used = 0;
}

void Runlist::del(Runable *run)
{
    enter();
    if(run->list != this) {
        leave();
        return;
    }

    if(!run->next && !run->prev) {
        if(first == run && last == run)
            first = last = NULL;
        else
            --used;
        run->list = NULL;
        leave();
        check();
        return;
    }

    if(run->next)
        run->next->prev = run->prev;
    else
        last = run->prev;

    if(run->prev)
        run->prev->next = run->next;
    else
        first = run->next;

    run->list = NULL;
    run->next = run->prev = NULL;
    leave();
    check();
    return;
}

void Runlist::set(unsigned count)
{
    limit = count;
    check();
}

bool Runlist::add(Runable *run)
{
    if(run->list)
        run->list->del(run);

    run->list = this;

    enter();
    if(used < limit) {
        ++used;
        leave();
        return true;
    }
    run->next = NULL;
    if(last) {
        run->prev = last;
        last = run;
    }
    else {
        run->prev = NULL;
        first = last = run;
    }
    leave();
    return false;
}

void Runlist::check(void)
{
    Runable *run;

    for(;;) {
        enter();
        if(used >= limit || !first) {
            leave();
            return;
        }
        run = first;
        first = run->next;
        if(first)
            first->prev = NULL;
        else
            last = NULL;
        run->next = run->prev = NULL;
        if(run->list == this)
            ++used;
        else
            run = NULL;
        leave();
        if(run)
            run->ready();
    }
}

Runable::Runable()
{
    list = NULL;
    next = prev = NULL;
}

bool Runable::starting(Runlist *list)
{
    stoping();
    return list->add(this);
}

void Runable::stoping(void)
{
    if(list)
        list->del(this);
}

Runable::~Runable()
{
    stoping();
}

#ifdef  CCXX_NAMESPACES
}
#endif

/** EMACS **
 * Local variables:
 * mode: c++
 * c-basic-offset: 4
 * End:
 */