source: MondoRescue/branches/stable/mindi-busybox/e2fsprogs/blkid/devname.c@ 821

Last change on this file since 821 was 821, checked in by Bruno Cornec, 18 years ago

Addition of busybox 1.2.1 as a mindi-busybox new package
This should avoid delivering binary files in mindi not built there (Fedora and Debian are quite serious about that)
File size: 8.4 KB
RevLine 
[821]1/*
2 * devname.c - get a dev by its device inode name
3 *
4 * Copyright (C) Andries Brouwer
5 * Copyright (C) 1999, 2000, 2001, 2002, 2003 Theodore Ts'o
6 * Copyright (C) 2001 Andreas Dilger
7 *
8 * %Begin-Header%
9 * This file may be redistributed under the terms of the
10 * GNU Lesser General Public License.
11 * %End-Header%
12 */
13
14#include <stdio.h>
15#include <string.h>
16#if HAVE_UNISTD_H
17#include <unistd.h>
18#endif
19#include <stdlib.h>
20#include <string.h>
21#include <ctype.h>
22#if HAVE_SYS_TYPES_H
23#include <sys/types.h>
24#endif
25#if HAVE_SYS_STAT_H
26#include <sys/stat.h>
27#endif
28#if HAVE_ERRNO_H
29#include <errno.h>
30#endif
31#if HAVE_SYS_MKDEV_H
32#include <sys/mkdev.h>
33#endif
34#include <time.h>
35
36#include "blkidP.h"
37
38/*
39 * Find a dev struct in the cache by device name, if available.
40 *
41 * If there is no entry with the specified device name, and the create
42 * flag is set, then create an empty device entry.
43 */
44blkid_dev blkid_get_dev(blkid_cache cache, const char *devname, int flags)
45{
46 blkid_dev dev = NULL, tmp;
47 struct list_head *p;
48
49 if (!cache || !devname)
50 return NULL;
51
52 list_for_each(p, &cache->bic_devs) {
53 tmp = list_entry(p, struct blkid_struct_dev, bid_devs);
54 if (strcmp(tmp->bid_name, devname))
55 continue;
56
57 DBG(DEBUG_DEVNAME,
58 printf("found devname %s in cache\n", tmp->bid_name));
59 dev = tmp;
60 break;
61 }
62
63 if (!dev && (flags & BLKID_DEV_CREATE)) {
64 dev = blkid_new_dev();
65 if (!dev)
66 return NULL;
67 dev->bid_name = blkid_strdup(devname);
68 dev->bid_cache = cache;
69 list_add_tail(&dev->bid_devs, &cache->bic_devs);
70 cache->bic_flags |= BLKID_BIC_FL_CHANGED;
71 }
72
73 if (flags & BLKID_DEV_VERIFY)
74 dev = blkid_verify(cache, dev);
75 return dev;
76}
77
78/*
79 * Probe a single block device to add to the device cache.
80 */
81static void probe_one(blkid_cache cache, const char *ptname,
82 dev_t devno, int pri)
83{
84 blkid_dev dev = NULL;
85 struct list_head *p;
86 const char **dir;
87 char *devname = NULL;
88
89 /* See if we already have this device number in the cache. */
90 list_for_each(p, &cache->bic_devs) {
91 blkid_dev tmp = list_entry(p, struct blkid_struct_dev,
92 bid_devs);
93 if (tmp->bid_devno == devno) {
94 dev = blkid_verify(cache, tmp);
95 break;
96 }
97 }
98 if (dev && dev->bid_devno == devno)
99 goto set_pri;
100
101 /*
102 * Take a quick look at /dev/ptname for the device number. We check
103 * all of the likely device directories. If we don't find it, or if
104 * the stat information doesn't check out, use blkid_devno_to_devname()
105 * to find it via an exhaustive search for the device major/minor.
106 */
107 for (dir = blkid_devdirs; *dir; dir++) {
108 struct stat st;
109 char device[256];
110
111 sprintf(device, "%s/%s", *dir, ptname);
112 if ((dev = blkid_get_dev(cache, device, BLKID_DEV_FIND)) &&
113 dev->bid_devno == devno)
114 goto set_pri;
115
116 if (stat(device, &st) == 0 && S_ISBLK(st.st_mode) &&
117 st.st_rdev == devno) {
118 devname = blkid_strdup(device);
119 break;
120 }
121 }
122 if (!devname) {
123 devname = blkid_devno_to_devname(devno);
124 if (!devname)
125 return;
126 }
127 dev = blkid_get_dev(cache, devname, BLKID_DEV_NORMAL);
128 free(devname);
129
130set_pri:
131 if (!pri && !strncmp(ptname, "md", 2))
132 pri = BLKID_PRI_MD;
133 if (dev)
134 dev->bid_pri = pri;
135 return;
136}
137
138#define PROC_PARTITIONS "/proc/partitions"
139#define VG_DIR "/proc/lvm/VGs"
140
141/*
142 * This function initializes the UUID cache with devices from the LVM
143 * proc hierarchy. We currently depend on the names of the LVM
144 * hierarchy giving us the device structure in /dev. (XXX is this a
145 * safe thing to do?)
146 */
147#ifdef VG_DIR
148#include <dirent.h>
149static dev_t lvm_get_devno(const char *lvm_device)
150{
151 FILE *lvf;
152 char buf[1024];
153 int ma, mi;
154 dev_t ret = 0;
155
156 DBG(DEBUG_DEVNAME, printf("opening %s\n", lvm_device));
157 if ((lvf = fopen(lvm_device, "r")) == NULL) {
158 DBG(DEBUG_DEVNAME, printf("%s: (%d) %s\n", lvm_device, errno,
159 strerror(errno)));
160 return 0;
161 }
162
163 while (fgets(buf, sizeof(buf), lvf)) {
164 if (sscanf(buf, "device: %d:%d", &ma, &mi) == 2) {
165 ret = makedev(ma, mi);
166 break;
167 }
168 }
169 fclose(lvf);
170
171 return ret;
172}
173
174static void lvm_probe_all(blkid_cache cache)
175{
176 DIR *vg_list;
177 struct dirent *vg_iter;
178 int vg_len = strlen(VG_DIR);
179 dev_t dev;
180
181 if ((vg_list = opendir(VG_DIR)) == NULL)
182 return;
183
184 DBG(DEBUG_DEVNAME, printf("probing LVM devices under %s\n", VG_DIR));
185
186 while ((vg_iter = readdir(vg_list)) != NULL) {
187 DIR *lv_list;
188 char *vdirname;
189 char *vg_name;
190 struct dirent *lv_iter;
191
192 vg_name = vg_iter->d_name;
193 if (!strcmp(vg_name, ".") || !strcmp(vg_name, ".."))
194 continue;
195 vdirname = xmalloc(vg_len + strlen(vg_name) + 8);
196 sprintf(vdirname, "%s/%s/LVs", VG_DIR, vg_name);
197
198 lv_list = opendir(vdirname);
199 free(vdirname);
200 if (lv_list == NULL)
201 continue;
202
203 while ((lv_iter = readdir(lv_list)) != NULL) {
204 char *lv_name, *lvm_device;
205
206 lv_name = lv_iter->d_name;
207 if (!strcmp(lv_name, ".") || !strcmp(lv_name, ".."))
208 continue;
209
210 lvm_device = xmalloc(vg_len + strlen(vg_name) +
211 strlen(lv_name) + 8);
212 sprintf(lvm_device, "%s/%s/LVs/%s", VG_DIR, vg_name,
213 lv_name);
214 dev = lvm_get_devno(lvm_device);
215 sprintf(lvm_device, "%s/%s", vg_name, lv_name);
216 DBG(DEBUG_DEVNAME, printf("LVM dev %s: devno 0x%04X\n",
217 lvm_device,
218 (unsigned int) dev));
219 probe_one(cache, lvm_device, dev, BLKID_PRI_LVM);
220 free(lvm_device);
221 }
222 closedir(lv_list);
223 }
224 closedir(vg_list);
225}
226#endif
227
228#define PROC_EVMS_VOLUMES "/proc/evms/volumes"
229
230static int
231evms_probe_all(blkid_cache cache)
232{
233 char line[100];
234 int ma, mi, sz, num = 0;
235 FILE *procpt;
236 char device[110];
237
238 procpt = fopen(PROC_EVMS_VOLUMES, "r");
239 if (!procpt)
240 return 0;
241 while (fgets(line, sizeof(line), procpt)) {
242 if (sscanf (line, " %d %d %d %*s %*s %[^\n ]",
243 &ma, &mi, &sz, device) != 4)
244 continue;
245
246 DBG(DEBUG_DEVNAME, printf("Checking partition %s (%d, %d)\n",
247 device, ma, mi));
248
249 probe_one(cache, device, makedev(ma, mi), BLKID_PRI_EVMS);
250 num++;
251 }
252 fclose(procpt);
253 return num;
254}
255
256/*
257 * Read the device data for all available block devices in the system.
258 */
259int blkid_probe_all(blkid_cache cache)
260{
261 FILE *proc;
262 char line[1024];
263 char ptname0[128], ptname1[128], *ptname = 0;
264 char *ptnames[2];
265 dev_t devs[2];
266 int ma, mi;
267 unsigned long long sz;
268 int lens[2] = { 0, 0 };
269 int which = 0, last = 0;
270
271 ptnames[0] = ptname0;
272 ptnames[1] = ptname1;
273
274 if (!cache)
275 return -BLKID_ERR_PARAM;
276
277 if (cache->bic_flags & BLKID_BIC_FL_PROBED &&
278 time(0) - cache->bic_time < BLKID_PROBE_INTERVAL)
279 return 0;
280
281 blkid_read_cache(cache);
282 evms_probe_all(cache);
283#ifdef VG_DIR
284 lvm_probe_all(cache);
285#endif
286
287 proc = fopen(PROC_PARTITIONS, "r");
288 if (!proc)
289 return -BLKID_ERR_PROC;
290
291 while (fgets(line, sizeof(line), proc)) {
292 last = which;
293 which ^= 1;
294 ptname = ptnames[which];
295
296 if (sscanf(line, " %d %d %llu %128[^\n ]",
297 &ma, &mi, &sz, ptname) != 4)
298 continue;
299 devs[which] = makedev(ma, mi);
300
301 DBG(DEBUG_DEVNAME, printf("read partition name %s\n", ptname));
302
303 /* Skip whole disk devs unless they have no partitions
304 * If we don't have a partition on this dev, also
305 * check previous dev to see if it didn't have a partn.
306 * heuristic: partition name ends in a digit.
307 *
308 * Skip extended partitions.
309 * heuristic: size is 1
310 *
311 * FIXME: skip /dev/{ida,cciss,rd} whole-disk devs
312 */
313
314 lens[which] = strlen(ptname);
315 if (isdigit(ptname[lens[which] - 1])) {
316 DBG(DEBUG_DEVNAME,
317 printf("partition dev %s, devno 0x%04X\n",
318 ptname, (unsigned int) devs[which]));
319
320 if (sz > 1)
321 probe_one(cache, ptname, devs[which], 0);
322 lens[which] = 0;
323 lens[last] = 0;
324 } else if (lens[last] && strncmp(ptnames[last], ptname,
325 lens[last])) {
326 DBG(DEBUG_DEVNAME,
327 printf("whole dev %s, devno 0x%04X\n",
328 ptnames[last], (unsigned int) devs[last]));
329 probe_one(cache, ptnames[last], devs[last], 0);
330 lens[last] = 0;
331 }
332 }
333
334 /* Handle the last device if it wasn't partitioned */
335 if (lens[which])
336 probe_one(cache, ptname, devs[which], 0);
337
338 fclose(proc);
339
340 cache->bic_time = time(0);
341 cache->bic_flags |= BLKID_BIC_FL_PROBED;
342 blkid_flush_cache(cache);
343 return 0;
344}
345
346#ifdef TEST_PROGRAM
347int main(int argc, char **argv)
348{
349 blkid_cache cache = NULL;
350 int ret;
351
352 blkid_debug_mask = DEBUG_ALL;
353 if (argc != 1) {
354 fprintf(stderr, "Usage: %s\n"
355 "Probe all devices and exit\n", argv[0]);
356 exit(1);
357 }
358 if ((ret = blkid_get_cache(&cache, bb_dev_null)) != 0) {
359 fprintf(stderr, "%s: error creating cache (%d)\n",
360 argv[0], ret);
361 exit(1);
362 }
363 if (blkid_probe_all(cache) < 0)
364 printf("%s: error probing devices\n", argv[0]);
365
366 blkid_put_cache(cache);
367 return (0);
368}
369#endif
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