commands/search.c

   1 /* search.c - search devices based on a file or a filesystem label */
   2 /*
   3  *  GRUB  --  GRand Unified Bootloader
   4  *  Copyright (C) 2005,2007,2008,2009  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/types.h>
  21 #include <grub/misc.h>
  22 #include <grub/mm.h>
  23 #include <grub/err.h>
  24 #include <grub/dl.h>
  25 #include <grub/device.h>
  26 #include <grub/file.h>
  27 #include <grub/env.h>
  28 #include <grub/extcmd.h>
  29
  30 static const struct grub_arg_option options[] =
  31   {
  32     {"file",            'f', 0, "search devices by a file", 0, 0},
  33     {"label",           'l', 0, "search devices by a filesystem label", 0, 0},
  34     {"fs-uuid",         'u', 0, "search devices by a filesystem UUID", 0, 0},
  35     {"set",             's', GRUB_ARG_OPTION_OPTIONAL, "set a variable to the first device found", "VAR", ARG_TYPE_STRING},
  36     {"no-floppy",       'n', 0, "do not probe any floppy drive", 0, 0},
  37     {0, 0, 0, 0, 0, 0}
  38   };
  39
  40 enum options
  41   {
  42     SEARCH_FILE,
  43     SEARCH_LABEL,
  44     SEARCH_FS_UUID,
  45     SEARCH_SET,
  46     SEARCH_NO_FLOPPY,
  47  };
  48
  49 static void
  50 search_fs (const char *key, const char *var, int no_floppy, enum options type)
  51 {
  52   int count = 0;
  53   char *buf = NULL;
  54   grub_fs_autoload_hook_t saved_autoload;
  55
  56   auto int iterate_device (const char *name);
  57   int iterate_device (const char *name)
  58   {
  59     int found = 0;
  60
  61     /* Skip floppy drives when requested.  */
  62     if (no_floppy &&
  63         name[0] == 'f' && name[1] == 'd' && name[2] >= '0' && name[2] <= '9')
  64       return 0;
  65
  66     if (type == SEARCH_FILE)
  67       {
  68         grub_size_t len;
  69         char *p;
  70         grub_file_t file;
  71
  72         len = grub_strlen (name) + 2 + grub_strlen (key) + 1;
  73         p = grub_realloc (buf, len);
  74         if (! p)
  75           return 1;
  76
  77         buf = p;
  78         grub_sprintf (buf, "(%s)%s", name, key);
  79
  80         file = grub_file_open (buf);
  81         if (file)
  82           {
  83             found = 1;
  84             grub_file_close (file);
  85           }
  86       }
  87     else
  88       {
  89         /* type is SEARCH_FS_UUID or SEARCH_LABEL */
  90         grub_device_t dev;
  91         grub_fs_t fs;
  92         int (*compare_fn) (const char *, const char *);
  93         char *quid;
  94
  95         dev = grub_device_open (name);
  96         if (dev)
  97           {
  98             fs = grub_fs_probe (dev);
  99             compare_fn =
 100               (type == SEARCH_FS_UUID) ? grub_strcasecmp : grub_strcmp;
 101
 102             if (fs && ((type == SEARCH_FS_UUID) ? fs->uuid : fs->label))
 103               {
 104                 if (type == SEARCH_FS_UUID)
 105                   fs->uuid (dev, &quid);
 106                 else
 107                   fs->label (dev, &quid);
 108
 109                 if (grub_errno == GRUB_ERR_NONE && quid)
 110                   {
 111                     if (compare_fn (quid, key) == 0)
 112                       found = 1;
 113
 114                     grub_free (quid);
 115                   }
 116               }
 117
 118             grub_device_close (dev);
 119           }
 120       }
 121
 122     if (found)
 123       {
 124         count++;
 125         if (var)
 126           grub_env_set (var, name);
 127         else
 128           grub_printf (" %s", name);
 129       }
 130
 131     grub_errno = GRUB_ERR_NONE;
 132     return (found && var);
 133   }
 134
 135   /* First try without autoloading if we're setting variable. */
 136   if (var)
 137     {
 138       saved_autoload = grub_fs_autoload_hook;
 139       grub_fs_autoload_hook = 0;
 140       grub_device_iterate (iterate_device);
 141
 142       /* Restore autoload hook.  */
 143       grub_fs_autoload_hook = saved_autoload;
 144
 145       /* Retry with autoload if nothing found.  */
 146       if (grub_errno == GRUB_ERR_NONE && count == 0)
 147         grub_device_iterate (iterate_device);
 148     }
 149   else
 150     grub_device_iterate (iterate_device);
 151
 152   grub_free (buf);
 153
 154   if (grub_errno == GRUB_ERR_NONE && count == 0)
 155     grub_error (GRUB_ERR_FILE_NOT_FOUND, "no such device: %s", key);
 156 }
 157
 158 static grub_err_t
 159 grub_cmd_search (grub_extcmd_t cmd, int argc, char **args)
 160 {
 161   struct grub_arg_list *state = cmd->state;
 162   const char *var = 0;
 163
 164   if (argc == 0)
 165     return grub_error (GRUB_ERR_INVALID_COMMAND, "no argument specified");
 166
 167   if (state[SEARCH_SET].set)
 168     var = state[SEARCH_SET].arg ? state[SEARCH_SET].arg : "root";
 169
 170   if (state[SEARCH_LABEL].set)
 171     search_fs (args[0], var, state[SEARCH_NO_FLOPPY].set, SEARCH_LABEL);
 172   else if (state[SEARCH_FS_UUID].set)
 173     search_fs (args[0], var, state[SEARCH_NO_FLOPPY].set, SEARCH_FS_UUID);
 174   else if (state[SEARCH_FILE].set)
 175     search_fs (args[0], var, state[SEARCH_NO_FLOPPY].set, SEARCH_FILE);
 176   else
 177     return grub_error (GRUB_ERR_INVALID_COMMAND, "unspecified search type");
 178
 179   return grub_errno;
 180 }
 181
 182 static grub_extcmd_t cmd;
 183
 184 GRUB_MOD_INIT(search)
 185 {
 186   cmd =
 187     grub_register_extcmd ("search", grub_cmd_search,
 188                           GRUB_COMMAND_FLAG_BOTH,
 189                           "search [-f|-l|-u|-s|-n] NAME",
 190                           "Search devices by file, filesystem label or filesystem UUID."
 191                           " If --set is specified, the first device found is"
 192                           " set to a variable. If no variable name is"
 193                           " specified, \"root\" is used.",
 194                           options);
 195 }
 196
 197 GRUB_MOD_FINI(search)
 198 {
 199   grub_unregister_extcmd (cmd);
 200 }