amiga-tz/library/time_timer.c

//--------------------------------------------------------------------------//
// This file is in the public domain.                                       //
//--------------------------------------------------------------------------//

#include "time_header.h"
#include <devices/timer.h>

struct Device*       TimerBase;
struct MsgPort*      TimerPort;
struct timerequest*  TimeRequest;

int CreateTimer()
{
    int error;

    TimerPort = CreateMsgPort();
    if (TimerPort == NULL) {
        return 1;
    }

    TimeRequest = (struct timerequest*)CreateIORequest(
                      TimerPort,
                      sizeof(struct timerequest)
                  );

    if (TimeRequest == NULL) {
        DeleteMsgPort(TimerPort);
        return 2;
    }

    error = OpenDevice(
                (STRPTR)TIMERNAME,
                UNIT_MICROHZ,
                (struct IORequest*)TimeRequest,
                0
            );

    if (error != 0)
    {
        DeleteIORequest((struct IORequest*)TimeRequest);
        DeleteMsgPort(TimerPort);
        return 3;
    }

    TimerBase = (struct Device*)TimeRequest->tr_node.io_Device;
    return 0;
}

void DeleteTimer()
{
    if (TimeRequest != NULL) {
        if (!CheckIO((struct IORequest*)TimeRequest)) {
            WaitIO((struct IORequest*)TimeRequest);
        }

        CloseDevice((struct IORequest*)TimeRequest);
        DeleteIORequest((struct IORequest*)TimeRequest);

        TimeRequest = NULL;
    }

    if (TimerPort != NULL) {
        DeleteMsgPort(TimerPort);
        TimerPort = NULL;
    }
}