commands/blocklist.c

   1 /* blocklist.c - print the block list of a file */
   2 /*
   3  *  GRUB  --  GRand Unified Bootloader
   4  *  Copyright (C) 2006,2007  Free Software Foundation, Inc.
   5  *
   6  *  GRUB is free software: you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation, either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  GRUB is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <grub/dl.h>
  21 #include <grub/misc.h>
  22 #include <grub/file.h>
  23 #include <grub/mm.h>
  24 #include <grub/disk.h>
  25 #include <grub/partition.h>
  26 #include <grub/command.h>
  27
  28 static grub_err_t
  29 grub_cmd_blocklist (grub_command_t cmd __attribute__ ((unused)),
  30                     int argc, char **args)
  31 {
  32   grub_file_t file;
  33   char buf[GRUB_DISK_SECTOR_SIZE];
  34   unsigned long start_sector = 0;
  35   unsigned num_sectors = 0;
  36   int num_entries = 0;
  37   grub_disk_addr_t part_start = 0;
  38   grub_partition_t part;
  39
  40   auto void NESTED_FUNC_ATTR read_blocklist (grub_disk_addr_t sector, unsigned offset,
  41                             unsigned length);
  42   auto void NESTED_FUNC_ATTR print_blocklist (grub_disk_addr_t sector, unsigned num,
  43                              unsigned offset, unsigned length);
  44
  45   void NESTED_FUNC_ATTR read_blocklist (grub_disk_addr_t sector, unsigned offset,
  46                        unsigned length)
  47     {
  48       if (num_sectors > 0)
  49         {
  50           if (start_sector + num_sectors == sector
  51               && offset == 0 && length == GRUB_DISK_SECTOR_SIZE)
  52             {
  53               num_sectors++;
  54               return;
  55             }
  56
  57           print_blocklist (start_sector, num_sectors, 0, 0);
  58           num_sectors = 0;
  59         }
  60
  61       if (offset == 0 && length == GRUB_DISK_SECTOR_SIZE)
  62         {
  63           start_sector = sector;
  64           num_sectors++;
  65         }
  66       else
  67         print_blocklist (sector, 0, offset, length);
  68     }
  69
  70   void NESTED_FUNC_ATTR print_blocklist (grub_disk_addr_t sector, unsigned num,
  71                         unsigned offset, unsigned length)
  72     {
  73       if (num_entries++)
  74         grub_printf (",");
  75
  76       grub_printf ("%llu", (unsigned long long) (sector - part_start));
  77       if (num > 0)
  78         grub_printf ("+%u", num);
  79       if (offset != 0 || length != 0)
  80         grub_printf ("[%u-%u]", offset, offset + length);
  81     }
  82
  83   if (argc < 1)
  84     return grub_error (GRUB_ERR_BAD_ARGUMENT, "no file specified");
  85
  86   file = grub_file_open (args[0]);
  87   if (! file)
  88     return grub_errno;
  89
  90   if (! file->device->disk)
  91     return grub_error (GRUB_ERR_BAD_DEVICE,
  92                        "this command is available only for disk devices.");
  93
  94   part_start = 0;
  95   for (part = file->device->disk->partition; part; part = part->parent)
  96     part_start += grub_partition_get_start (part);
  97
  98   file->read_hook = read_blocklist;
  99
 100   while (grub_file_read (file, buf, sizeof (buf)) > 0)
 101     ;
 102
 103   if (num_sectors > 0)
 104     print_blocklist (start_sector, num_sectors, 0, 0);
 105
 106   grub_file_close (file);
 107
 108   return grub_errno;
 109 }
 110
 111 static grub_command_t cmd;
 112 \f
 113 GRUB_MOD_INIT(blocklist)
 114 {
 115   cmd = grub_register_command ("blocklist", grub_cmd_blocklist,
 116                                "blocklist FILE", "Print a block list.");
 117 }
 118
 119 GRUB_MOD_FINI(blocklist)
 120 {
 121   grub_unregister_command (cmd);
 122 }