resources/fat.h

   1 /* Quarn OS
   2  *
   3  * FAT filesystem
   4  *
   5  * Copyright (C) 2008-2009 Pawel Dziepak
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  */
  22
  23 #include "fs.h"
  24 #include "arch/low/general.h"
  25 #include "libs/string.h"
  26
  27 namespace resources {
  28         class fat : public fs {
  29         private:
  30                 enum fat_attribs {
  31                         fat_read_only = 1,
  32                         fat_hidden = 2,
  33                         fat_system = 4,
  34                         fat_volume_id = 8,
  35                         fat_directory = 0x10,
  36                         fat_archive = 0x20
  37                 };
  38
  39                 struct dir_entry {
  40                         u8 name[8];
  41                         u8 format[3];
  42                         u8 attr;
  43                         u8 reserved[10];
  44                         u16 time;
  45                         u16 date;
  46                         u16 cluster;
  47                         u32 size;
  48                 }  __attribute__((__packed__));
  49
  50                 static const int mbr_sectors_per_fat = 0x16;
  51                 static const int mbr_root_entries = 0x11;
  52                 static const int mbr_fat_count = 0x10;
  53                 static const int mbr_reserved_sectors = 0xd;
  54                 static const int mbr_dev_desc = 0x15;
  55                 static const int mbr_fsid = 0x36;
  56
  57                 dir_entry *root_dir;
  58                 dir_entry *current_dir;
  59
  60                 unsigned char *mbr;
  61                 unsigned char *main_fat;
  62
  63                 int find_file(const char *filename);
  64                 inline short get_cluster_val(int index);
  65                 inline void set_cluster_val(int n, int val);
  66                 void filename_to_fatname(const char *filename, char *fatname);
  67                 void fatname_to_filename(const char *filename, char *fatname);
  68
  69                 bool mounted;
  70         public:
  71                 fat();
  72
  73                 void load_file(const string &filename, buffer &addr);
  74                 file::file_meta load_meta(const string &filename);
  75
  76                 list<p<file> > list_directory(const string &dirname);
  77
  78                 void save_file(const string &filename, buffer &addr);
  79
  80                 bool mount(p<block>);
  81
  82                 static void register_type();
  83
  84         };
  85 }