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/command.h>
29 #include <grub/search.h>
30 #include <grub/i18n.h>
31 #include <grub/disk.h>
32 #include <grub/partition.h>
33
34 GRUB_MOD_LICENSE ("GPLv3+");
35
36 struct cache_entry
37 {
38 struct cache_entry *next;
39 char *key;
40 char *value;
41 };
42
43 static struct cache_entry *cache;
44
45 void
46 FUNC_NAME (const char *key, const char *var, int no_floppy,
47 char **hints, unsigned nhints)
48 {
49 int count = 0;
50 int is_cache = 0;
51 grub_fs_autoload_hook_t saved_autoload;
52
53 auto int iterate_device (const char *name);
54 int iterate_device (const char *name)
55 {
56 int found = 0;
57
58 /* Skip floppy drives when requested. */
59 if (no_floppy &&
60 name[0] == 'f' && name[1] == 'd' && name[2] >= '0' && name[2] <= '9')
61 return 0;
62
63 #ifdef DO_SEARCH_FS_UUID
64 #define compare_fn grub_strcasecmp
65 #else
66 #define compare_fn grub_strcmp
67 #endif
68
69 #ifdef DO_SEARCH_FILE
70 {
71 char *buf;
72 grub_file_t file;
73
74 buf = grub_xasprintf ("(%s)%s", name, key);
75 if (! buf)
76 return 1;
77
78 grub_file_filter_disable_compression ();
79 file = grub_file_open (buf);
80 if (file)
81 {
82 found = 1;
83 grub_file_close (file);
84 }
85 grub_free (buf);
86 }
87 #else
88 {
89 /* SEARCH_FS_UUID or SEARCH_LABEL */
90 grub_device_t dev;
91 grub_fs_t fs;
92 char *quid;
93
94 dev = grub_device_open (name);
95 if (dev)
96 {
97 fs = grub_fs_probe (dev);
98
99 #ifdef DO_SEARCH_FS_UUID
100 #define read_fn uuid
101 #else
102 #define read_fn label
103 #endif
104
105 if (fs && fs->read_fn)
106 {
107 fs->read_fn (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 #endif
122
123 if (!is_cache && found && count == 0)
124 {
125 struct cache_entry *cache_ent;
126 cache_ent = grub_malloc (sizeof (*cache_ent));
127 if (cache_ent)
128 {
129 cache_ent->key = grub_strdup (key);
130 cache_ent->value = grub_strdup (name);
131 if (cache_ent->value && cache_ent->key)
132 {
133 cache_ent->next = cache;
134 cache = cache_ent;
135 }
136 else
137 {
138 grub_free (cache_ent->value);
139 grub_free (cache_ent->key);
140 grub_free (cache_ent);
141 grub_errno = GRUB_ERR_NONE;
142 }
143 }
144 else
145 grub_errno = GRUB_ERR_NONE;
146 }
147
148 if (found)
149 {
150 count++;
151 if (var)
152 grub_env_set (var, name);
153 else
154 grub_printf (" %s", name);
155 }
156
157 grub_errno = GRUB_ERR_NONE;
158 return (found && var);
159 }
160
161 auto int part_hook (grub_disk_t disk, const grub_partition_t partition);
162 int part_hook (grub_disk_t disk, const grub_partition_t partition)
163 {
164 char *partition_name, *devname;
165 int ret;
166
167 partition_name = grub_partition_get_name (partition);
168 if (! partition_name)
169 return 1;
170
171 devname = grub_xasprintf ("%s,%s", disk->name, partition_name);
172 grub_free (partition_name);
173 if (!devname)
174 return 1;
175 ret = iterate_device (devname);
176 grub_free (devname);
177
178 return ret;
179 }
180
181 auto void try (void);
182 void try (void)
183 {
184 unsigned i;
185 struct cache_entry **prev;
186 struct cache_entry *cache_ent;
187
188 for (prev = &cache, cache_ent = *prev; cache_ent;
189 prev = &cache_ent->next, cache_ent = *prev)
190 if (compare_fn (cache_ent->key, key) == 0)
191 break;
192 if (cache_ent)
193 {
194 is_cache = 1;
195 if (iterate_device (cache_ent->value))
196 {
197 is_cache = 0;
198 return;
199 }
200 is_cache = 0;
201 /* Cache entry was outdated. Remove it. */
202 if (!count)
203 {
204 grub_free (cache_ent->key);
205 grub_free (cache_ent->value);
206 grub_free (cache_ent);
207 *prev = cache_ent->next;
208 }
209 }
210
211 for (i = 0; i < nhints; i++)
212 {
213 char *end;
214 if (!hints[i][0])
215 continue;
216 end = hints[i] + grub_strlen (hints[i]) - 1;
217 if (*end == ',')
218 *end = 0;
219 if (iterate_device (hints[i]))
220 {
221 if (!*end)
222 *end = ',';
223 return;
224 }
225 if (!*end)
226 {
227 grub_device_t dev;
228 int ret;
229 dev = grub_device_open (hints[i]);
230 if (!dev)
231 {
232 if (!*end)
233 *end = ',';
234 continue;
235 }
236 if (!dev->disk)
237 {
238 grub_device_close (dev);
239 if (!*end)
240 *end = ',';
241 continue;
242 }
243 ret = grub_partition_iterate (dev->disk, part_hook);
244 if (!*end)
245 *end = ',';
246 grub_device_close (dev);
247 if (ret)
248 return;
249 }
250 }
251 grub_device_iterate (iterate_device);
252 }
253
254 /* First try without autoloading if we're setting variable. */
255 if (var)
256 {
257 saved_autoload = grub_fs_autoload_hook;
258 grub_fs_autoload_hook = 0;
259 try ();
260
261 /* Restore autoload hook. */
262 grub_fs_autoload_hook = saved_autoload;
263
264 /* Retry with autoload if nothing found. */
265 if (grub_errno == GRUB_ERR_NONE && count == 0)
266 try ();
267 }
268 else
269 try ();
270
271 if (grub_errno == GRUB_ERR_NONE && count == 0)
272 grub_error (GRUB_ERR_FILE_NOT_FOUND, "no such device: %s", key);
273 }
274
275 static grub_err_t
276 grub_cmd_do_search (grub_command_t cmd __attribute__ ((unused)), int argc,
277 char **args)
278 {
279 if (argc == 0)
280 return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("one argument expected"));
281
282 FUNC_NAME (args[0], argc == 1 ? 0 : args[1], 0, (args + 2),
283 argc > 2 ? argc - 2 : 0);
284
285 return grub_errno;
286 }
287
288 static grub_command_t cmd;
289
290 #ifdef DO_SEARCH_FILE
291 GRUB_MOD_INIT(search_fs_file)
292 #elif defined (DO_SEARCH_FS_UUID)
293 GRUB_MOD_INIT(search_fs_uuid)
294 #else
295 GRUB_MOD_INIT(search_label)
296 #endif
297 {
298 cmd =
299 grub_register_command (COMMAND_NAME, grub_cmd_do_search,
300 N_("NAME [VARIABLE] [HINTS]"),
301 HELP_MESSAGE);
302 }
303
304 #ifdef DO_SEARCH_FILE
305 GRUB_MOD_FINI(search_fs_file)
306 #elif defined (DO_SEARCH_FS_UUID)
307 GRUB_MOD_FINI(search_fs_uuid)
308 #else
309 GRUB_MOD_FINI(search_label)
310 #endif
311 {
312 grub_unregister_command (cmd);
313 }