qa_defer.cpp

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// Product: QF/C++
// Last Updated for Version: 4.3.00
// Date of the Last Update:  Nov 01, 2011
//
//                    Q u a n t u m     L e a P s
//                    ---------------------------
//                    innovating embedded systems
//
// Copyright (C) 2002-2011 Quantum Leaps, LLC. All rights reserved.
//
// This software may be distributed and modified under the terms of the GNU
// General Public License version 2 (GPL) as published by the Free Software
// Foundation and appearing in the file GPL.TXT included in the packaging of
// this file. Please note that GPL Section 2[b] requires that all works based
// on this software must also be made publicly available under the terms of
// the GPL ("Copyleft").
//
// Alternatively, this software may be distributed and modified under the
// terms of Quantum Leaps commercial licenses, which expressly supersede
// the GPL and are specifically designed for licensees interested in
// retaining the proprietary status of their code.
//
// Contact information:
// Quantum Leaps Web site:  http://www.quantum-leaps.com
// e-mail:                  info@quantum-leaps.com
#include "qf_pkg.h"
#include "qassert.h"


#ifdef Q_USE_NAMESPACE
namespace QP {
#endif

Q_DEFINE_THIS_MODULE(qa_defer)

//............................................................................
void QActive::defer(QEQueue *eq, QEvent const *e) {
    eq->postFIFO(e);
}
//............................................................................
uint8_t QActive::recall(QEQueue *eq) {
    QEvent const *e = eq->get();    // try to get an event from deferred queue
    if (e != (QEvent *)0) {                                // event available?

        postLIFO(e);      // post it to the front of the Active Object's queue

        QS_CRIT_STAT_
        QF_CRIT_ENTRY_();

        if (EVT_POOL_ID(e) != (uint8_t)0) {          // is it a dynamic event?

            // after posting to the AO's queue the event must be referenced
            // at least twice: once in the deferred event queue (eq->get()
            // did NOT decrement the reference counter) and once in the
            // AO's event queue.
            Q_ASSERT(EVT_REF_CTR(e) > (uint8_t)1);

            // we need to decrement the reference counter once, to account
            // for removing the event from the deferred event queue.
            //
            EVT_DEC_REF_CTR(e);             // decrement the reference counter
        }

        QF_CRIT_EXIT_();

        return (uint8_t)1;                                   // event recalled
    }
    else {
        return (uint8_t)0;                               // event not recalled
    }
}

#ifdef Q_USE_NAMESPACE
}                                                              // namespace QP
#endif