software_watchdog.c File Reference

Software Watchdog More...

#include <libmoxa_rtu.h>

Functions
int	main (int argc, char *argv[])

Detailed Description

Software Watchdog

Copyright

Moxa Inc.

Date

04-10-2013

Author

Eddy Kao

Version

V1.0

Introduction:
Software Watchdog is used to guarantee a critical section which must be executed at least every N seconds.
If the critical section is not executed after N seconds, the watchdog will restart the system.
Example:
1. Using default: ./software_watchdog
2. Setting Ack Time: ./software_watchdog -t5000
Default:
Ack Time = 10000 ms (10 seconds)
 SOFTWARE_WATCHDOG_MIN_TIME 
 SOFTWARE_WATCHDOG_MAX_TIME 
Help:

root@Moxa:/tmp#./software_watchdog -h
Software Watchdog.

Usage: ./software_watchdog [OPTIONS]

Options:
        -t       Ack Time [50-60000]. Default Ack Time = 10000 ms

Library:
SoftwareWatchdog APIs

Function Documentation

int main	(	int	argc,
		char *	argv[]
	)

/*******************************************************************************
 * Copyright Moxa Inc.
 *
 * Software Watchdog
 *
 * Date          Author            Comment
 * 04-10-2013   Eddy Kao     Created.
 ******************************************************************************/

#include <libmoxa_rtu.h>

int main(int argc, char *argv[])
{
    int retval = 0;
    UINT32 rc = 0;
    UINT32 ackTime = 10 * 1000; // 10 seconds
    struct swtd_setting setting;

    while((retval = getopt(argc, argv, "ht:")) != -1)
    {
        switch(retval)
        {
            case 't':
                ackTime = atoi(optarg);

                if(ackTime < SOFTWARE_WATCHDOG_MIN_TIME || ackTime > SOFTWARE_WATCHDOG_MAX_TIME)
                {
                    printf("Invalid Ack Time\r\n");
                    exit(1);
                }

                break;

            case '?':
            case 'h':
            default:
                printf("Software Watchdog.\n\n");
                printf("Usage: ./software_watchdog [OPTIONS]\n\n");
                printf("Options:\n");
                printf("\t%-8s Ack Time [%d-%d]. Default Ack Time = %d ms\n", "-t", SOFTWARE_WATCHDOG_MIN_TIME, SOFTWARE_WATCHDOG_MAX_TIME, ackTime);
                printf("\n");
                return 0;
        }
    }

    rc = MX_RTU_SWTD_Enable(ackTime);

    if(rc != MISC_ERR_OK)
    {
        printf("MX_RTU_SWTD_Enable(%d), return code = %d\r\n", ackTime, rc);
        exit(1);
    }

    memset(&setting, 0, sizeof(struct swtd_setting));
    rc = MX_RTU_SWTD_Get_Setting(&setting);

    if(rc != MISC_ERR_OK)
    {
        printf("MX_RTU_SWTD_Get_Setting(&setting), return code = %d\r\n", rc);
        exit(1);
    }
    else
    {
        printf("Software Watchdog: enable = %d, time = %d ms\r\n", setting.enable, setting.time);
    }

    while(1)
    {
        //This is a critical section, and it should be executed at least every N seconds.

        //do something

        //If the critical section is not executed over N seconds, watchdog will restart system.
        rc = MX_RTU_SWTD_Ack();

        if(rc != MISC_ERR_OK)
        {
            printf("MX_RTU_SWTD_Ack(), return code = %d\r\n", rc);
            exit(1);
        }
    }

    return 0;
}