/*  Program to dump the FAT of an MS-DOS format disk
 *
 *  Copyright (c) 1991 Shal Farley
 *  		       Cheshire Engineering Corporation
 *  		       650 Sierra Madre Villa Avenue, Suite 201
 *  		       Pasadena, California 91107
 *  		       (818) 351-5493
 *                     (818) 351-8645 FAX
 *                     shal@alumni.caltech.edu
 *
 *  This software may be used and distributed for any purpose without license or
 *  royalty payments so long as the above copyright notice is preserved. If you
 *  have any comments, bug fixes, improvements, or new programs based upon this
 *  software I'd like to hear from you.
 */
#include <stdio.h>
#include "msport.h"
#include "msfio.h"
#include "msdir.h"


    static  USHORT
UchFromPch(pch)                 /* Get unsigned char from (char *) */
    char   *pch;
{
    return 0xFF & (USHORT)*pch;
}


    static USHORT
GetFE_0(pFE)                    /* Return least entry */
    MSFE   *pFE;
{
    return( ((USHORT)pFE->b1<<8 ) + (UchFromPch(&pFE->b0)) & 0xFFF );
}


    static USHORT
GetFE_1(pFE)                    /* Return higher entry */
    MSFE   *pFE;
{
    return( ((USHORT)pFE->b2<<8) + (UchFromPch(&pFE->b1)) >> 4 & 0xFFF);
}


main(argc,argv)
    int argc;
    char * argv[];
{
    MSDEV  *pd;                 /* Pointer to device struct */
    int     nClust;             /* Number of useable clusters */
    int     i;                  /* loop counter */

    if ( argc != 2) {
        fprintf(stderr, "Usage: MSFAT device-or-file-name");
        exit(1);
    }
    if ( (pd = msdopen(argv[1])) == NULL) {
        msperror("?MSFAT-F");
        exit(1);
    }
    if (pd->fRT11) {
        fprintf(stderr, "?MSFAT-F-Device has RT-11 directory\n");
        exit(1);
    }
    if (!pd->fValid & !pd->fMaybe) {
        fprintf(stderr, "?MSFAT-I-Device is not MS-DOS format\n");
        exit(1);
    }
    /*
     * Dump the FAT table
     */
    nClust = pd->nsTotal
            -pd->nsBoot
            -(pd->nFATs*pd->nsFAT)
            -(pd->nDirEntries*sizeof(MSDE)/SECTOR);
    printf(" %d clusters available (0x002 .. 0x%03X)", nClust, nClust+1);
    /*
     * Perhaps this loop should insert page breaks? Nah...
     */
    for (i = 0; i < nClust+2; i ++) {
        if ( (i & 0xF) == 0) printf("\n%03X/ ", i);
        printf(" %03X", msfeclust(i, pd));
    }
    printf("\n");
    exit(0);
}