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/zfs/zfs.h>
26 #include <grub/device.h>
27 #include <grub/file.h>
28 #include <grub/env.h>
29 #include <grub/command.h>
30 #include <grub/search.h>
31 #include <grub/i18n.h>
32 #include <grub/disk.h>
33 #include <grub/partition.h>
34
35 GRUB_MOD_LICENSE ("GPLv3+");
36
37 struct cache_entry
38 {
39 struct cache_entry *next;
40 char *key;
41 char *value;
42 };
43
44 static struct cache_entry *cache;
45
46 void
47 FUNC_NAME (const char *key, const char *var, int no_floppy,
48 char **hints, unsigned nhints, int mirror)
49 {
50 int count = 0;
51 int is_cache = 0;
52 grub_uint64_t txg = 0;
53 grub_fs_autoload_hook_t saved_autoload;
54
55 auto int iterate_device (const char *name);
56 int iterate_device (const char *name)
57 {
58 int found = 0;
59
60 /* Skip floppy drives when requested. */
61 if (no_floppy &&
62 name[0] == 'f' && name[1] == 'd' && name[2] >= '0' && name[2] <= '9')
63 return 0;
64
65 #ifdef DO_SEARCH_FS_UUID
66 #define compare_fn grub_strcasecmp
67 #else
68 #define compare_fn grub_strcmp
69 #endif
70
71 #ifdef DO_SEARCH_FILE
72 {
73 char *buf;
74 grub_file_t file;
75
76 buf = grub_xasprintf ("(%s)%s", name, key);
77 if (! buf)
78 return 1;
79
80 grub_file_filter_disable_compression ();
81 file = grub_file_open (buf);
82 if (file)
83 {
84 found = 1;
85 grub_file_close (file);
86 }
87 grub_free (buf);
88 }
89 #else
90 {
91 /* SEARCH_FS_UUID or SEARCH_LABEL */
92 grub_device_t dev;
93 grub_fs_t fs;
94 char *quid;
95
96 dev = grub_device_open (name);
97 if (dev)
98 {
99 fs = grub_fs_probe (dev);
100
101 #ifdef DO_SEARCH_FS_UUID
102 #define read_fn uuid
103 #else
104 #define read_fn label
105 #endif
106
107 if (fs && fs->read_fn)
108 {
109 fs->read_fn (dev, &quid);
110
111 if (grub_errno == GRUB_ERR_NONE && quid)
112 {
113 if (compare_fn (quid, key) == 0)
114 found = 1;
115
116 grub_free (quid);
117 }
118 }
119
120 grub_device_close (dev);
121 }
122 }
123 #endif
124
125 if (!is_cache && found && count == 0)
126 {
127 struct cache_entry *cache_ent;
128 cache_ent = grub_malloc (sizeof (*cache_ent));
129 if (cache_ent)
130 {
131 cache_ent->key = grub_strdup (key);
132 cache_ent->value = grub_strdup (name);
133 if (cache_ent->value && cache_ent->key)
134 {
135 cache_ent->next = cache;
136 cache = cache_ent;
137 }
138 else
139 {
140 grub_free (cache_ent->value);
141 grub_free (cache_ent->key);
142 grub_free (cache_ent);
143 grub_errno = GRUB_ERR_NONE;
144 }
145 }
146 else
147 grub_errno = GRUB_ERR_NONE;
148 }
149
150 if (found)
151 {
152 count++;
153 if (var) {
154 if (! mirror) {
155 grub_env_set (var, name);
156 } else {
157 grub_uint64_t tmp_txg = 0;
158 char * nvlist = NULL;
159 grub_device_t dev = grub_device_open (name);
160 if (! dev) {
161 grub_errno = GRUB_ERR_BAD_DEVICE;
162 return 0;
163 }
164 grub_errno = grub_zfs_fetch_nvlist (dev, &nvlist);
165 grub_device_close (dev);
166 if (grub_errno)
167 return 0;
168 grub_zfs_nvlist_lookup_uint64 (nvlist, ZPOOL_CONFIG_POOL_TXG, &tmp_txg);
169 if (tmp_txg > txg) {
170 grub_env_set (var, name);
171 txg = tmp_txg;
172 }
173 grub_free (nvlist);
174 }
175 } else {
176 grub_printf (" %s", name);
177 }
178 }
179
180 grub_errno = GRUB_ERR_NONE;
181 return (found && var && !mirror);
182 }
183
184 auto int part_hook (grub_disk_t disk, const grub_partition_t partition);
185 int part_hook (grub_disk_t disk, const grub_partition_t partition)
186 {
187 char *partition_name, *devname;
188 int ret;
189
190 partition_name = grub_partition_get_name (partition);
191 if (! partition_name)
192 return 1;
193
194 devname = grub_xasprintf ("%s,%s", disk->name, partition_name);
195 grub_free (partition_name);
196 if (!devname)
197 return 1;
198 ret = iterate_device (devname);
199 grub_free (devname);
200
201 return ret;
202 }
203
204 auto void try (void);
205 void try (void)
206 {
207 unsigned i;
208 struct cache_entry **prev;
209 struct cache_entry *cache_ent;
210
211 for (prev = &cache, cache_ent = *prev; cache_ent;
212 prev = &cache_ent->next, cache_ent = *prev)
213 if (compare_fn (cache_ent->key, key) == 0)
214 break;
215 if (cache_ent)
216 {
217 is_cache = 1;
218 if (iterate_device (cache_ent->value))
219 {
220 is_cache = 0;
221 return;
222 }
223 is_cache = 0;
224 /* Cache entry was outdated. Remove it. */
225 if (!count)
226 {
227 grub_free (cache_ent->key);
228 grub_free (cache_ent->value);
229 grub_free (cache_ent);
230 *prev = cache_ent->next;
231 }
232 }
233
234 for (i = 0; i < nhints; i++)
235 {
236 char *end;
237 if (!hints[i][0])
238 continue;
239 end = hints[i] + grub_strlen (hints[i]) - 1;
240 if (*end == ',')
241 *end = 0;
242 if (iterate_device (hints[i]))
243 {
244 if (!*end)
245 *end = ',';
246 return;
247 }
248 if (!*end)
249 {
250 grub_device_t dev;
251 int ret;
252 dev = grub_device_open (hints[i]);
253 if (!dev)
254 {
255 if (!*end)
256 *end = ',';
257 continue;
258 }
259 if (!dev->disk)
260 {
261 grub_device_close (dev);
262 if (!*end)
263 *end = ',';
264 continue;
265 }
266 ret = grub_partition_iterate (dev->disk, part_hook);
267 if (!*end)
268 *end = ',';
269 grub_device_close (dev);
270 if (ret)
271 return;
272 }
273 }
274 grub_device_iterate (iterate_device);
275 }
276
277 /* First try without autoloading if we're setting variable. */
278 if (var)
279 {
280 saved_autoload = grub_fs_autoload_hook;
281 grub_fs_autoload_hook = 0;
282 try ();
283
284 /* Restore autoload hook. */
285 grub_fs_autoload_hook = saved_autoload;
286
287 /* Retry with autoload if nothing found. */
288 if (grub_errno == GRUB_ERR_NONE && count == 0)
289 try ();
290 }
291 else
292 try ();
293
294 if (grub_errno == GRUB_ERR_NONE && count == 0)
295 grub_error (GRUB_ERR_FILE_NOT_FOUND, "no such device: %s", key);
296 }
297
298 static grub_err_t
299 grub_cmd_do_search (grub_command_t cmd __attribute__ ((unused)), int argc,
300 char **args)
301 {
302 if (argc == 0)
303 return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("one argument expected"));
304
305 FUNC_NAME (args[0], argc == 1 ? 0 : args[1], 0, (args + 2),
306 argc > 2 ? argc - 2 : 0, 0);
307
308 return grub_errno;
309 }
310
311 static grub_command_t cmd;
312
313 #ifdef DO_SEARCH_FILE
314 GRUB_MOD_INIT(search_fs_file)
315 #elif defined (DO_SEARCH_FS_UUID)
316 GRUB_MOD_INIT(search_fs_uuid)
317 #else
318 GRUB_MOD_INIT(search_label)
319 #endif
320 {
321 cmd =
322 grub_register_command (COMMAND_NAME, grub_cmd_do_search,
323 N_("NAME [VARIABLE] [HINTS]"),
324 HELP_MESSAGE);
325 }
326
327 #ifdef DO_SEARCH_FILE
328 GRUB_MOD_FINI(search_fs_file)
329 #elif defined (DO_SEARCH_FS_UUID)
330 GRUB_MOD_FINI(search_fs_uuid)
331 #else
332 GRUB_MOD_FINI(search_label)
333 #endif
334 {
335 grub_unregister_command (cmd);
336 }