fs/fdos/fs.c

   1 /*
   2  * (C) Copyright 2002
   3  * Stäubli Faverges - <www.staubli.com>
   4  * Pierre AUBERT  p.aubert@staubli.com
   5  *
   6  * See file CREDITS for list of people who contributed to this
   7  * project.
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License as
  11  * published by the Free Software Foundation; either version 2 of
  12  * the License, or (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  22  * MA 02111-1307 USA
  23  */
  24
  25 #include <common.h>
  26 #include <config.h>
  27 #include <malloc.h>
  28
  29 #if (CONFIG_COMMANDS & CFG_CMD_FDOS)
  30
  31 #include "dos.h"
  32 #include "fdos.h"
  33
  34
  35 /*-----------------------------------------------------------------------------
  36  * fill_fs -- Read info on file system
  37  *-----------------------------------------------------------------------------
  38  */
  39 static int fill_fs (BootSector_t *boot, Fs_t *fs)
  40 {
  41
  42     fs -> fat_start = __le16_to_cpu (boot -> nrsvsect);
  43     fs -> fat_len = __le16_to_cpu (boot -> fatlen);
  44     fs -> nb_fat = boot -> nfat;
  45
  46     fs -> dir_start = fs -> fat_start + fs -> nb_fat * fs -> fat_len;
  47     fs -> dir_len = __le16_to_cpu (boot -> dirents) * MDIR_SIZE / SZ_STD_SECTOR;
  48     fs -> cluster_size = boot -> clsiz;
  49     fs -> num_clus = (fs -> tot_sectors - fs -> dir_start - fs -> dir_len) / fs -> cluster_size;
  50
  51     return (0);
  52 }
  53
  54 /*-----------------------------------------------------------------------------
  55  * fs_init --
  56  *-----------------------------------------------------------------------------
  57  */
  58 int fs_init (Fs_t *fs)
  59 {
  60     BootSector_t *boot;
  61
  62     /* Initialize physical device                                            */
  63     if (dev_open () < 0) {
  64         PRINTF ("Unable to initialize the fdc\n");
  65         return (-1);
  66     }
  67     init_subdir ();
  68
  69     /* Allocate space for read the boot sector                               */
  70     if ((boot = (BootSector_t *)malloc (sizeof (BootSector_t))) == NULL) {
  71         PRINTF ("Unable to allocate space for boot sector\n");
  72         return (-1);
  73     }
  74
  75     /* read boot sector                                                      */
  76     if (dev_read (boot, 0, 1)){
  77         PRINTF ("Error during boot sector read\n");
  78         free (boot);
  79         return (-1);
  80     }
  81
  82     /* we verify it'a a DOS diskette                                         */
  83     if (boot -> jump [0] !=  JUMP_0_1 && boot -> jump [0] !=  JUMP_0_2) {
  84         PRINTF ("Not a DOS diskette\n");
  85         free (boot);
  86         return (-1);
  87     }
  88
  89     if (boot -> descr < MEDIA_STD) {
  90         /* We handle only recent medias (type F0)                            */
  91         PRINTF ("unrecognized diskette type\n");
  92         free (boot);
  93         return (-1);
  94     }
  95
  96     if (check_dev (boot, fs) < 0) {
  97         PRINTF ("Bad diskette\n");
  98         free (boot);
  99         return (-1);
 100     }
 101
 102     if (fill_fs (boot, fs) < 0) {
 103         free (boot);
 104
 105         return (-1);
 106     }
 107
 108     /* Read FAT                                                              */
 109     if (read_fat (boot, fs) < 0) {
 110         free (boot);
 111         return (-1);
 112     }
 113
 114     free (boot);
 115     return (0);
 116 }
 117
 118 #endif