The Datafile PD-CD 4/DATAFILE_PDCD4.iso/utilities/utilsp/rink010/Demo/c/rinkdemo

Text File | 1995-06-25 | 4.8 KB | 210 lines

// rinkdemo - main program

// (c) Ben Summers 1995

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "kernel.h"
#include "rink.h"

// this demonstration of rink shows the recommended way of loading
// and using rink segments. However, you don't have to do it like
// this - the run time system just provides some basic routine
// to handle segments, and doesn't force any method of use on you.

typedef int BOOL;

#define TRUE    1
#define FALSE   0

// the function prototypes of the functions in segments.

typedef int (*SegmentStart)(char *, int);
typedef void (*SegmentDo)(void);
typedef int (*SegmentFinish)(int);

typedef void (*SegmentNamed)(void);

// and a structure to hold info about the segments we've loaded

typedef struct {
    rink_seghandle Handle;
    struct {
        SegmentStart Start;       // there should be the same number
        SegmentDo Do;             // of fns here that there are in the header
        SegmentFinish Finish;     // and they must be in the same order
    } fns;
} SegmentInfo;

// a rink_check structure for loading segments

rink_check CheckBlock;





// an error wrapping function

BOOL ErrWrap(void *err, char *Doing)
{
    char *String = ((char *)err) + 4;

    if(err == 0)
        return TRUE;

    printf("Error in %s: %s\n", Doing, String);

    return FALSE;
}




// some data for segments to access

int NumberInParent = 56;



// a function for the segments to call

int FunctionInParentProgram(int Number)
{
    printf("FunctionInParentProgram called, Number = %d\n\n", Number);

    return Number / 2;
}





// a routine to load a segment. Takes a pointer to the name
// of the directory the code and links files are stored and
// a Segment info to put the interesting stuff in.

BOOL LoadSegment(SegmentInfo *pSegment, char *Name)
{
    char CodeName[256];
    char LinksName[256];
    _rink_fn *PtrArray;
    rink_version *Version;
    int Fn;

    // make filename of the code and links
    sprintf(CodeName, "%s.Code", Name);
    sprintf(LinksName, "%s.Links", Name);

    // load the segment...
    if(!ErrWrap(rink_load(CodeName, LinksName, &pSegment->Handle, &CheckBlock), "segment load"))
        return FALSE;

    // OK, let's have a look at the version of the segment we've just loaded.
    // It might be nice to check them to see that it's acceptable.
    // It is a bad plan to alter the returned structure.
    Version = rink_readversion(pSegment->Handle);

    printf("Segment '%s': Main version = %d, Code version = %d\n\n", Name, Version->main, Version->code);

    // right, now get the function pointers...
    PtrArray = (_rink_fn *)&pSegment->fns;
    for(Fn = 0; Fn < (sizeof(pSegment->fns) / sizeof(_rink_fn)); Fn++)
    {
        // for each function, get a pointer from the run time system
        PtrArray[Fn] = rink_fn(pSegment->Handle, Fn);

        // check that it's not zero - ie no function
        if(PtrArray[Fn] == 0)
        {
            printf("Function not present in segment %s\n\n", Name);
            return FALSE;
        }
    }

    // done

    return TRUE;
}





// routine to unload segments

BOOL UnloadSegment(SegmentInfo *pSegment)
{
    // could call a finalise function here...

    // unload the segment from memory
    rink_unload(pSegment->Handle);

    return TRUE;
}





// the main function

int main(void)
{
    SegmentInfo Segment1;
    SegmentInfo Segment2;
    int l;
    SegmentNamed Fn;
    char *Name;

    printf("rink demonstration program\n(c) Ben Summers 1995\n\n");

    // set up the check block
    strcpy(CheckBlock.id, "rinkdemo");
    CheckBlock.main_version = 100;
    CheckBlock.code_version = 0;

    // load the two segments
    printf("Loading segments...\n\n");
    if(!LoadSegment(&Segment1, "Segment1"))
        return 1;

    if(!LoadSegment(&Segment2, "Segment2"))
        return 1;

    printf("Segments loaded\n\n");

    // call a few functions... start with the start functions.
    printf("Segment1 Start returned %d\n\n", Segment1.fns.Start("A nice little string", 42));
    printf("Segment2 Start returned %d\n\n", Segment2.fns.Start("A pretty string", 19));

    // and the do functions
    Segment1.fns.Do();
    Segment2.fns.Do();

    // and finish off with a final
    printf("Segment1 Finish returned %d\n\n", Segment1.fns.Finish(12));
    printf("Segment2 Finish returned %d\n\n", Segment2.fns.Finish(90));

    // call some named functions in Segment1. Now, I'm not really sure what you'd
    // do with them, but they're there just in case.

    printf("Calling named functions from Segment1...\n\n");
    l = 0;
    do {
        Fn = (SegmentNamed)rink_enum_named(Segment1.Handle, &l, &Name);
        printf("*** calling %s\n", Name);
        Fn();
    } while(l >= 0);

    // unload them now we've finished
    UnloadSegment(&Segment1);
    UnloadSegment(&Segment2);

    // all done.
    return 0;
}