No Fragments Archive 12: Textmags & Docs/nf_archive_12.iso/MAGS/SOURCES/ATARI_SRC.ZIP/atari source/HDX_BACK/HDX503/ZERO.C

C/C++ Source or Header | 2001-02-09 | 5.5 KB | 205 lines

/* zero.c */

/* 16-Mar-88  ml.    split up assist.c into this and markbad.c    */
/* 11-Dec-87  ml.    added BSL concept to zero().            */
/* 01-Nov-88  jye.  change add codes so that can be used for MS-DOS */


#include "osbind.h"
#include "obdefs.h"
#include "mydefs.h"
#include "part.h"
#include "bsl.h"
#include "addr.h"


extern long gbslsiz();
extern long bslsiz;
extern BYTE *bsl;
extern long ratio;


/*
 * Zero logical dev
 *
 */
zero(ldev)
int ldev;
{
    UWORD pdev,ndirs, fatsiz;
    UWORD bps, sects;
    SECTOR fat0, data, size, dummy=0;
    char bs[512];
    char *newbs;
    BOOT *boot;
    int  bootsiz, i, ret;
    char *buf1;
    long remsect;
    long datsect;
    long datclst;
    long fatclst;
    long entsect;
    long nsect;

    if ((ret = rdsects(ldev, 1, bs, (SECTOR)0)) != 0) {
        if (tsterr(ret) != OK)
            err(bootread);
        return ERROR;
    }

    /*
     * Zero file system's boot sector, FAT and DIR sectors.
     */
    boot = (BOOT *)bs;
    gw((UWORD *)&boot->b_ndirs[0], &ndirs);
    gw((UWORD *)&boot->b_spf[0], &fatsiz);
    gw((UWORD *)&boot->b_bps[0], &bps);
    gw((UWORD *)&boot->b_nsects[0], §s);
    nsect = (long)sects;
    ratio = (long)(bps / BPS);
    size = (long)BPS * ratio;
    if ((newbs = (char *)Malloc(size)) <= 0)    {
        err(nomemory);
        if (newbs > 0) Mfree((long)newbs);
        return ERROR;
    }

    if ((ret = zerosect(ldev, (SECTOR)0,
                    (1 + fatsiz*2 + ndirs*BPDIR/bps)*((UWORD)ratio))) != 0) {
        if (tsterr(ret) != OK)
            err(hdrwrite);
        return ERROR;
    }


    /* Put boot information into new boot sector */
    if ((ret = rdsects(ldev, (UWORD)ratio, newbs, (SECTOR)0)) != 0) {
        if (tsterr(ret) != OK)
            err(bootread);
        return ERROR;
    }
    bootsiz = sizeof(BOOT);
    for (i = 0; i < bootsiz; i++)
        newbs[i] = bs[i];

    /* put the last long word data into the new boot sector */
    *(long *)&newbs[508] = *(long *)&bs[508];

    /* Write boot information back to disk */
    if ((ret = wrsects(ldev, (UWORD)ratio, newbs, (SECTOR)0)) != 0) {
        if (tsterr(ret) != OK)
            err(bootwrit);
        return ERROR;
    }


    /* # of sectors in datas:
     *                 datsect   = nsect - boot - 2*fatsiz - size of dir
     *                           = nsect-boot-2*fatsiz-(ndirs*BPDIR)/bps
     * # of clusters in datas:
     *                datclst      = # of sectors in datas / SPC
     * # of clusters(entries) in Fat:
     *                fatclst   = fatsiz * (bps/2)
     * # of sectors need in fat talbe for datclst:
     *                entsect   = datclst / (bps/2)
     * # of sectors need to remodify to 0xffff:
     *                remsect   = fatsiz - entsect
     */

    datsect = nsect - 1 - 2*fatsiz - (ndirs*BPDIR)/bps;
    datclst = datsect / SPC;
    fatclst = (long)fatsiz * (bps/2);
    entsect = datclst / (bps/2);
    remsect = ((long)fatsiz - entsect)*size;


    /* # of sectors need to remodify to 0xffff */
    if ((buf1 = (char *)Malloc(remsect)) <= 0)    {
        err(nomemory);
        if (newbs > 0) Mfree((long)newbs);
        if (buf1 > 0) Mfree((long)buf1);
        return ERROR;
    }

    /*
     * Apr-23-93 jye: To fixed the write over to next partitiona in the Gemdos
     *                  , here just set those entries in Fat table, which don't
     *                  correspond to the availble date sectors in the partition.
     *                  The pointers should be:
     *                      (boot+datclst/(bps/2))*ratio and
     *                    (boot+fatsiz+datclst/(bps/2))*ratio
     */
    if ((ret = rdsects(ldev, (UWORD)(remsect/BPS), buf1,
                         (1+datclst/(bps/2))*ratio)) != OK) {
        if (tsterr(ret) != OK)
            err(bootwrit);
        return ERROR;
    }
    /* fill the last sectors of FAT start at last entry with the 0xffff */
    /* +2 is for the two reserved entries in the fat table */
    fillfat(buf1, ((datclst % (bps/2))+2)*2, remsect, 0xffff);
    if ((ret = wrsects(ldev,(UWORD)(remsect/BPS),buf1,
                             (1+datclst/(bps/2))*ratio) != OK) ||
        (ret = wrsects(ldev,(UWORD)(remsect/BPS),buf1,
                             (1+fatsiz+datclst/(bps/2))*ratio) != OK)) {
        if (tsterr(ret) != OK)
            err(bootwrit);
        return ERROR;
    }
    /* Apr-23-93 jye: Add above codes to fix the Gemdos over write next
     *                   partition.
     */



    /*
     * Make first 2 entries in FATs more IBM-like.
     */
    if ((ret = rdsects(ldev,(UWORD)ratio,newbs,ratio)) != 0) {/* read FAT 0 */
        return ERROR;
    }
    *(UWORD *)&newbs[0] = 0xf8ff;
    *(UWORD *)&newbs[2] = 0xffff;

    /* write FAT 0 and FAT 1 */
    if ((ret = wrsects(ldev, (UWORD)ratio, newbs, ratio)) != 0
    || (ret = wrsects(ldev, (UWORD)ratio, newbs,
                (SECTOR)((1+fatsiz)*ratio))) != 0) {
    if (tsterr(ret) != OK)
        err(fatwrite);
    return ERROR;
    }

    pdev = ldev;
    log2phys(&pdev, &dummy);

    /* Get size of BSL */
    if ((bslsiz = gbslsiz(pdev)) > 0L) {
        /* Allocate memory for existing BSL */
        if ((bsl = (BYTE *)mymalloc((int)bslsiz << 9)) <= 0)
            return err(nomemory);

        /* Read in BSL */
        if ((dummy = rdbsl(pdev)) != OK) {
            free(bsl);
            if (dummy = INVALID)
                err(cruptbsl);
            return ERROR;
        }

    fat0 = ratio;
    data = (SECTOR)1 + (SECTOR)fatsiz*2 + (SECTOR)(ndirs*BPDIR/bps);

        /* Mark Vendor or User Bad Sectors into FAT */
    if (bsl2fat(ldev, fat0, fatsiz*((UWORD)ratio), data*ratio, MEDIA) != OK) {
            free(bsl);
            return ERROR;
        }
    free(bsl);
    }
    if (newbs > 0)    Mfree((long)newbs);
    if (buf1 > 0) Mfree((long)buf1);
    return OK;
}