fs.c
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/*
* (C) Copyright 2002
* Stäubli Faverges - <www.staubli.com>
* Pierre AUBERT p.aubert@staubli.com
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <config.h>
#include <malloc.h>
#include "dos.h"
#include "fdos.h"
/*-----------------------------------------------------------------------------
* fill_fs -- Read info on file system
*-----------------------------------------------------------------------------
*/
static int fill_fs (BootSector_t *boot, Fs_t *fs)
{
fs -> fat_start = __le16_to_cpu (boot -> nrsvsect);
fs -> fat_len = __le16_to_cpu (boot -> fatlen);
fs -> nb_fat = boot -> nfat;
fs -> dir_start = fs -> fat_start + fs -> nb_fat * fs -> fat_len;
fs -> dir_len = __le16_to_cpu (boot -> dirents) * MDIR_SIZE / SZ_STD_SECTOR;
fs -> cluster_size = boot -> clsiz;
fs -> num_clus = (fs -> tot_sectors - fs -> dir_start - fs -> dir_len) / fs -> cluster_size;
return (0);
}
/*-----------------------------------------------------------------------------
* fs_init --
*-----------------------------------------------------------------------------
*/
int fs_init (Fs_t *fs)
{
BootSector_t *boot;
/* Initialize physical device */
if (dev_open () < 0) {
PRINTF ("Unable to initialize the fdc\n");
return (-1);
}
init_subdir ();
/* Allocate space for read the boot sector */
if ((boot = (BootSector_t *)malloc (sizeof (BootSector_t))) == NULL) {
PRINTF ("Unable to allocate space for boot sector\n");
return (-1);
}
/* read boot sector */
if (dev_read (boot, 0, 1)){
PRINTF ("Error during boot sector read\n");
free (boot);
return (-1);
}
/* we verify it'a a DOS diskette */
if (boot -> jump [0] != JUMP_0_1 && boot -> jump [0] != JUMP_0_2) {
PRINTF ("Not a DOS diskette\n");
free (boot);
return (-1);
}
if (boot -> descr < MEDIA_STD) {
/* We handle only recent medias (type F0) */
PRINTF ("unrecognized diskette type\n");
free (boot);
return (-1);
}
if (check_dev (boot, fs) < 0) {
PRINTF ("Bad diskette\n");
free (boot);
return (-1);
}
if (fill_fs (boot, fs) < 0) {
free (boot);
return (-1);
}
/* Read FAT */
if (read_fat (boot, fs) < 0) {
free (boot);
return (-1);
}
free (boot);
return (0);
}