bsp.cpp

Quantum Platform(QP) is a family of very lightweight, state machine-based frameworks for embedded sy

//////////////////////////////////////////////////////////////////////////////
// Product: QDPP example, 80x86, Linux/P-threads, g++
// Last Updated for Version: 3.3.00
// Date of the Last Update:  Jan 24, 2007
//
//                    Q u a n t u m     L e a P s
//                    ---------------------------
//                    innovating embedded systems
//
// Copyright (C) 2002-2007 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:                  [e-mail]
//////////////////////////////////////////////////////////////////////////////
#include "qf_port.h"
#include "qassert.h"
#include "qdpp.h"

#include <stdlib.h>
#include <stdio.h>
#include <sys/select.h>
#include <termios.h>
#include <unistd.h>

Q_DEFINE_THIS_FILE

//............................................................................
static void *idleThread(void *me) {         // the expected P-Thread signature
    struct timeval timeout = { 0 };                    // timeout for select()
    struct termios tio;                        // modified terminal attributes

    tcgetattr(0, &tio);              // obtain the current terminal attributes
    tio.c_lflag &= ~(ICANON | ECHO);      // disable the canonical mode & echo
    tcsetattr(0, TCSANOW, &tio);                     // set the new attributes

    while (QF_running_) {
        fd_set con;                         // FD set representing the console
        FD_ZERO(&con);
        FD_SET(0, &con);
        timeout.tv_usec = 8000;

           // sleep for the full tick or until a console input arrives, NOTE01
        if (0 != select(1, &con, 0, 0, &timeout)) {     // any descriptor set?
            char ch;
            read(0, &ch, 1);
            if (ch == '\33') {                                 // ESC pressed?
                QF::publish(Q_NEW(QEvent, TERMINATE_SIG));
            }
        }
    }

    return (void *)0;                                        // return success
}
//............................................................................
void BSP_init(int argc, char *argv[]) {
    pthread_attr_t attr;
    struct sched_param param;
    pthread_t idle;

    pthread_attr_init(&attr);

    // SCHED_FIFO corresponds to real-time preemptive priority-based scheduler
    // NOTE: This scheduling policy requires the superuser priviledges
    pthread_attr_setschedpolicy(&attr, SCHED_FIFO);
    param.sched_priority = sched_get_priority_min(SCHED_FIFO);

    pthread_attr_setschedparam(&attr, &param);
    pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);

    if (pthread_create(&idle, &attr, &idleThread, 0) != 0) {
               // Creating the p-thread with the SCHED_FIFO policy failed.
               // Most probably this application has no superuser privileges,
               // so we just fall back to the default SCHED_OTHER policy
               // and priority 0.
        pthread_attr_setschedpolicy(&attr, SCHED_OTHER);
        param.sched_priority = 0;
        pthread_attr_setschedparam(&attr, &param);
        Q_ALLEGE(pthread_create(&idle, &attr, &idleThread, 0) == 0);
    }
    pthread_attr_destroy(&attr);
}
//............................................................................
void displyPhilStat(uint8_t n, char const *stat) {
    printf("Philosopher %2d is %s\n", (int)n, stat);
}
//............................................................................
void Q_assert_handler(char const Q_ROM * const Q_ROM_VAR file, int line) {
    fprintf(stderr, "Assertion failed in %s, line %d", file, line);
    QF::exit();
}


//////////////////////////////////////////////////////////////////////////////
//
// NOTE01:
// The select() system call seems to deliver the finest time granularity of
// 1 clock tick. The timeout value passed to select() is rounded up to the
// nearest tick (10 ms on desktop Linux). The timeout cannot be too short,
// because the system might choose to busy-wait for very short timeouts.
// An alternative, POSIX nanosleep() system call seems to deliver only 20ms
// granularity.
//
// Here the select() call is used not just as a fairly portable way to sleep
// with subsecond precision. The select() call is also used to detect any
// characters typed on the console to
//
// Also according to man pages, on Linux, the function select() modifies
// timeout to reflect the amount of time not slept; most other implementations
// do not do this. This causes problems both when Linux code which reads
// timeout is ported to other operating systems, and when code is ported to
// Linux that reuses a struct timeval for multiple selects in a loop without
// reinitializing it. Here the microsecond part of the structure is re-
// initialized before each select() call.
//