/*
 *  MSINIT.C     Program to initialize a disk in MS-DOS format
 *
 *  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>
#ifdef decus
#   include "msasse.h"
#else
#   include <string.h>
#   include <assert.h>
#   define zero(buf,size) memset(buf,0,size)
#endif
#include "msport.h"
#include "msdefs.h"
#include "msfio.h"
#include "msstat.h"
#include "msdir.h"
#include "mserrn.h"

main(argc,argv)
    int     argc;
    char   *argv[];
{
    UCHAR   buf[512];           /* A copy of the boot block */
    MSDEV  *pDEV;               /* The MS-DOS device */
    FILE   *pf;                 /* The corresponding RT-11 file */
    USHORT *pSig;               /* MS-DOS boot sector signature = 0xAA55 */
    MSBS   *pBS;                /* MS-DOS boot sector */
    int     size;               /* Size of FAT or Dir to allocate */
    int     temp;

    /*
     * Open the device and see what's in it
     */
    if ( argc != 2) {
        fprintf(stderr, "Usage: MSINIT device-or-file-name");
        exit(1);
    }
    if ( (pDEV = msdopen(argv[1])) == NULL) {
        msperror("?MSINIT-F");
        exit(1);
    }
    if (pDEV->fValid) {
        fprintf(stderr, "?MSINIT-I-Device has MS-DOS directory\n");
    }
    if (pDEV->fRT11) {
        fprintf(stderr, "?MSINIT-I-Device has RT-11 directory\n");
    }
    /*
     * Give the user a chance to back out
     */
    fprintf(stderr, "Initialize %s, Are you sure? ", argv[1]);
    fflush(stderr);
    if (toupper(getc(stdin)) != 'Y') exit(0);
    /*
     * Fill in the MSDEV structure
     */
    pDEV->fValid = TRUE;
    pDEV->nsTotal = 2400L;      /* Values for 1.2 MB 5.25" diskette */
    pDEV->nsBoot = 1;
    pDEV->nFATs = 2;
    pDEV->nsFAT = 7;
    pDEV->nDirEntries = 224;
    pDEV->nsCluster = 1;
    /*
     * Fill in the Boot block
     */
    zero(buf,SECTOR);
    pBS = &buf[MSVH_BS];
    strncpy(pBS->OemName, "MSFIO   ",8);  /* Oem Name */
    pBS->BytesPerSec[0] = LSB(512);
    pBS->BytesPerSec[1] = MSB(512);
    pBS->SecPerClust = pDEV->nsCluster;
    pBS->ResSectors[0] = pDEV->nsBoot;
    pBS->FATs = pDEV->nFATs;
    pBS->RootDirEnts[0] = LSB(pDEV->nDirEntries);
    pBS->RootDirEnts[1] = MSB(pDEV->nDirEntries);
    pBS->Sectors[0] = LSB(pDEV->nsTotal);
    pBS->Sectors[1] = MSB(pDEV->nsTotal);
    pBS->Media = 0xF9;              /* for 1.2 MB diskettes */
    pBS->FATsecs[0] = pDEV->nsFAT;
    pBS->SecPerTrack[0] = 15;       /* for 1.2 MB diskettes */
    pBS->Heads[0] = 2;              /* for 1.2 MB diskettes */
    pBS->BootSignature = 0x29;      /* Extended Boot Block */
    strncpy(pBS->VolumeLabel, "           ", 11);
    strncpy(pBS->FileSysType, "FAT12   ", 8);

    pSig = &buf[MSVH_SYSID];    /* Mark it as MS-DOS Structured */
    *pSig = 0xAA55;

    /*
     * Get the FILE pointer for the device we're initializing
     */
    pf = pDEV->pFILE;

#ifdef decus
    /*
     * LIE, CHEAT & STEAL.
     *
     * The DECUS-C library does not support update operations. So now we reach
     * into the guts of the library and do what a simple call to fseek() should
     * have done.
     */
    pf->_flag &= ~_IOREAD;      /* fwrite() doesn't like "r" files... */
    pf->_flag |=  _IORW;        /* (nobody checks this) */

    assert(pf->_base != NULL);  /* We'll have no accidents, please */
    pf->_cnt = pf->io_rbsz;     /* The buffer is empty (whole size avail) */
    pf->_ptr = pf->_base;       /* Point to the base */

    pf->io_bnbr = 0;            /* WHAM -- the block number we want */
#else
    if (fseek(pf,0L,SEEK_SET) != 0) die("Seek to zero failed");
#endif /* decus */

    if ( (temp=fwrite(&buf[0],1,SECTOR,pf)) != SECTOR) {
        fprintf(stderr, "fwrite returned %d\n", temp);
        die("Boot");
    }
    /* This is needed since (in decus CLIB) subsequent seeks won't bother */
    if (fflush(pf) != 0) die("Flush boot failed");
    /*
     * FAT -- We set this up and let msdclose() write it out.
     */
    size = pBS->FATsecs[0]*SECTOR;
    if (pDEV->pFAT == NULL) {
        pDEV->pFAT = malloc(size);
    }
    pDEV->fFAT = TRUE;          /* Mark it as "dirty" */
    zero(pDEV->pFAT,size);      /* Clear it */
    pDEV->pFAT[0] = pBS->Media; /* The first two entries are marked */
    pDEV->pFAT[1] = 0xFF;       /*  "  */
    pDEV->pFAT[2] = 0xFF;       /*  "  */

    /*
     * Dir -- We set this up and let msdclose() write it out.
     */
    size = ((pBS->RootDirEnts[0] & 0xFF) + (pBS->RootDirEnts[1] << 8))
            * sizeof(MSDE);
    if (pDEV->pDir == NULL) {
        pDEV->pDir = malloc(size);
    }
    pDEV->fDir = TRUE;          /* Mark it as "dirty" */
    zero(pDEV->pDir,size);      /* Clear it */

    msdclose(pDEV);
    if ( (pDEV = msdopen(argv[1])) == NULL) {
        msperror("?MSINIT-F");
        exit(1);
    }
    exit(0);
}


die(pch)
    char   *pch;
{
    if (pch != NULL) fprintf(stderr, "?MSINIT-I-%s\n", pch);
    msperror("?MSINIT-F");
    exit(1);
}