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authorDenis Vlasenko2008-10-19 19:36:30 +0000
committerDenis Vlasenko2008-10-19 19:36:30 +0000
commit582dff051459b1394a48dec1f29a29e2442661a0 (patch)
tree41835a2b323eefb403825db78c033a920f86b602 /util-linux/volume_id/get_devname.c
parentbff06fe02a3d5629b745d799c3b987888070dc20 (diff)
downloadbusybox-582dff051459b1394a48dec1f29a29e2442661a0.zip
busybox-582dff051459b1394a48dec1f29a29e2442661a0.tar.gz
volume identification: abolish /proc/partitions and /proc/cdroms
scanning. It does not catch volume managers and such. Adding even more cruft is bad, so I decided to simply scan /dev/* for any block devices. See how much better it finds devices now: # ./busybox_old blkid /dev/sda1: LABEL="/boot" UUID="7931e231-dcb4-4b6d-9301-f7354ae24061" /dev/dm-0: LABEL="Fedora-9-Live-x8" UUID="bb491e1e-1145-4f5b-b0ab-cbd2baf4f15a" /dev/dm-1: UUID="edc2a920-ef83-437e-ba64-d3b6dc851267" /dev/sdb1: UUID="6F84-ED0F" # ./busybox blkid /dev/sdb1: UUID="6F84-ED0F" /dev/root: LABEL="Fedora-9-Live-x8" UUID="bb491e1e-1145-4f5b-b0ab-cbd2baf4f15a" /dev/dm-1: UUID="edc2a920-ef83-437e-ba64-d3b6dc851267" /dev/dm-0: LABEL="Fedora-9-Live-x8" UUID="bb491e1e-1145-4f5b-b0ab-cbd2baf4f15a" /dev/sda1: LABEL="/boot" UUID="7931e231-dcb4-4b6d-9301-f7354ae24061" /dev/mapper/VolGroup00-LogVol01: UUID="edc2a920-ef83-437e-ba64-d3b6dc851267" /dev/mapper/VolGroup00-LogVol00: LABEL="Fedora-9-Live-x8" UUID="bb491e1e-1145-4f5b-b0ab-cbd2baf4f15a" function old new delta static.drive_name_string 12 - -12 append_mount_options 205 190 -15 volume_id_open_node 37 18 -19 uuidcache_check_device 485 257 -228 uuidcache_init 637 36 -601 ------------------------------------------------------------------------------ (add/remove: 0/1 grow/shrink: 0/4 up/down: 0/-875) Total: -875 bytes text data bss dec hex filename 792218 592 6648 799458 c32e2 busybox_old 791260 592 6648 798500 c2f24 busybox_unstripped
Diffstat (limited to 'util-linux/volume_id/get_devname.c')
-rw-r--r--util-linux/volume_id/get_devname.c249
1 files changed, 31 insertions, 218 deletions
diff --git a/util-linux/volume_id/get_devname.c b/util-linux/volume_id/get_devname.c
index 83c0856..e99c15b 100644
--- a/util-linux/volume_id/get_devname.c
+++ b/util-linux/volume_id/get_devname.c
@@ -22,38 +22,23 @@ static struct uuidCache_s {
/* Returns !0 on error.
* Otherwise, returns malloc'ed strings for label and uuid
- * (and they can't be NULL, although they can be "") */
-#if !ENABLE_FEATURE_VOLUMEID_ISO9660
-#define get_label_uuid(device, label, uuid, iso_only) \
- get_label_uuid(device, label, uuid)
-#endif
+ * (and they can't be NULL, although they can be "").
+ * NB: closes fd. */
static int
-get_label_uuid(const char *device, char **label, char **uuid, int iso_only)
+get_label_uuid(int fd, char **label, char **uuid)
{
int rv = 1;
uint64_t size;
struct volume_id *vid;
- vid = volume_id_open_node(device);
- if (!vid)
- return rv;
+ /* fd is owned by vid now */
+ vid = volume_id_open_node(fd);
- if (ioctl(vid->fd, BLKGETSIZE64, &size) != 0)
+ if (ioctl(/*vid->*/fd, BLKGETSIZE64, &size) != 0)
size = 0;
-#if ENABLE_FEATURE_VOLUMEID_ISO9660
- if ((iso_only ?
- volume_id_probe_iso9660(vid, 0) :
- volume_id_probe_all(vid, 0, size)
- ) != 0
- ) {
- goto ret;
- }
-#else
- if (volume_id_probe_all(vid, 0, size) != 0) {
+ if (volume_id_probe_all(vid, 0, size) != 0)
goto ret;
- }
-#endif
if (vid->label[0] != '\0' || vid->uuid[0] != '\0') {
*label = xstrndup(vid->label, sizeof(vid->label));
@@ -62,7 +47,7 @@ get_label_uuid(const char *device, char **label, char **uuid, int iso_only)
rv = 0;
}
ret:
- free_volume_id(vid);
+ free_volume_id(vid); /* also closes fd */
return rv;
}
@@ -91,204 +76,29 @@ uuidcache_addentry(char *device, /*int major, int minor,*/ char *label, char *uu
/* If get_label_uuid() on device_name returns success,
* add a cache entry for this device.
* If device node does not exist, it will be temporarily created. */
-#if !ENABLE_FEATURE_VOLUMEID_ISO9660
-#define uuidcache_check_device(device_name, ma, mi, iso_only) \
- uuidcache_check_device(device_name, ma, mi)
-#endif
-static void
-uuidcache_check_device(const char *device_name, int ma, int mi, int iso_only)
+static int FAST_FUNC
+uuidcache_check_device(const char *device,
+ struct stat *statbuf,
+ void *userData UNUSED_PARAM,
+ int depth UNUSED_PARAM)
{
- char *device, *last_slash;
- char *uuid, *label;
- char *ptr;
- int must_remove = 0;
- int added = 0;
-
- last_slash = NULL;
- device = xasprintf("/dev/%s", device_name);
- if (access(device, F_OK) != 0) {
- /* device does not exist, temporarily create */
- int slash_cnt = 0;
-
- if ((ma | mi) < 0)
- goto ret; /* we don't know major:minor! */
-
- ptr = device;
- while (*ptr)
- if (*ptr++ == '/')
- slash_cnt++;
- if (slash_cnt > 2) {
-// BUG: handles only slash_cnt == 3 case
- last_slash = strrchr(device, '/');
- *last_slash = '\0';
- if (mkdir(device, 0644)) {
- bb_perror_msg("can't create directory %s", device);
- *last_slash = '/';
- last_slash = NULL; /* prevents rmdir */
- } else {
- *last_slash = '/';
- }
- }
- mknod(device, S_IFBLK | 0600, makedev(ma, mi));
- must_remove = 1;
- }
+ char *uuid = uuid; /* for compiler */
+ char *label = label;
+ int fd;
- uuid = NULL;
- label = NULL;
- if (get_label_uuid(device, &label, &uuid, iso_only) == 0) {
- uuidcache_addentry(device, /*ma, mi,*/ label, uuid);
- /* "device" is owned by cache now, don't free */
- added = 1;
- }
+ if (!S_ISBLK(statbuf->st_mode))
+ return TRUE;
- if (must_remove)
- unlink(device);
- if (last_slash) {
- *last_slash = '\0';
- rmdir(device);
- }
- ret:
- if (!added)
- free(device);
-}
+ fd = open(device, O_RDONLY);
+ if (fd < 0)
+ return TRUE;
-/* Run uuidcache_check_device() for every device mentioned
- * in /proc/partitions */
-static void
-uuidcache_init_partitions(void)
-{
- char line[100];
- int ma, mi;
- unsigned long long sz;
- FILE *procpt;
- int firstPass;
- int handleOnFirst;
- char *chptr;
-
- procpt = xfopen_for_read("/proc/partitions");
-/*
-# cat /proc/partitions
-major minor #blocks name
-
- 8 0 293036184 sda
- 8 1 6835626 sda1
- 8 2 1 sda2
- 8 5 979933 sda5
- 8 6 15623181 sda6
- 8 7 97659103 sda7
- 8 8 171935631 sda8
-*/
- for (firstPass = 1; firstPass >= 0; firstPass--) {
- fseek(procpt, 0, SEEK_SET);
-
- while (fgets(line, sizeof(line), procpt)) {
- /* The original version of this code used sscanf, but
- diet's sscanf is quite limited */
- chptr = line;
- if (*chptr != ' ') continue;
- chptr = skip_whitespace(chptr);
-
- ma = bb_strtou(chptr, &chptr, 0);
- if (ma < 0) continue;
- chptr = skip_whitespace(chptr);
-
- mi = bb_strtou(chptr, &chptr, 0);
- if (mi < 0) continue;
- chptr = skip_whitespace(chptr);
-
- sz = bb_strtoull(chptr, &chptr, 0);
- if ((long long)sz == -1LL) continue;
- chptr = skip_whitespace(chptr);
-
- /* skip extended partitions (heuristic: size 1) */
- if (sz == 1)
- continue;
-
- *strchrnul(chptr, '\n') = '\0';
- /* now chptr => device name */
- dbg("/proc/partitions: maj:%d min:%d sz:%llu name:'%s'",
- ma, mi, sz, chptr);
- if (!chptr[0])
- continue;
-
- /* look only at md devices on first pass */
- handleOnFirst = (chptr[0] == 'm' && chptr[1] == 'd');
- if (firstPass != handleOnFirst)
- continue;
-
- /* heuristic: partition name ends in a digit */
- if (isdigit(chptr[strlen(chptr) - 1])) {
- uuidcache_check_device(chptr, ma, mi, 0);
- }
- }
+ /* get_label_uuid() closes fd in all cases (success & failure) */
+ if (get_label_uuid(fd, &label, &uuid) == 0) {
+ /* uuidcache_addentry() takes ownership of all three params */
+ uuidcache_addentry(xstrdup(device), /*ma, mi,*/ label, uuid);
}
-
- fclose(procpt);
-}
-
-static void
-dev_get_major_minor(char *device_name, int *major, int *minor)
-{
- char dev[16];
- char *dev_path;
- char *colon;
- int sz;
-
- dev_path = xasprintf("/sys/block/%s/dev", device_name);
- sz = open_read_close(dev_path, dev, sizeof(dev) - 1);
- if (sz < 0)
- goto ret;
- dev[sz] = '\0';
-
- colon = strchr(dev, ':');
- if (!colon)
- goto ret;
- *major = bb_strtou(dev, NULL, 10);
- *minor = bb_strtou(colon + 1, NULL, 10);
-
- ret:
- free(dev_path);
- return;
-}
-
-static void
-uuidcache_init_cdroms(void)
-{
-#define PROC_CDROMS "/proc/sys/dev/cdrom/info"
- char line[100];
- int ma, mi;
- FILE *proccd;
-
- proccd = fopen_for_read(PROC_CDROMS);
- if (!proccd) {
-// static smallint warn = 0;
-// if (!warn) {
-// warn = 1;
-// bb_error_msg("can't open %s, UUID and LABEL "
-// "conversion cannot be done for CD-Roms",
-// PROC_CDROMS);
-// }
- return;
- }
-
- while (fgets(line, sizeof(line), proccd)) {
- static const char drive_name_string[] ALIGN1 = "drive name:";
-
- if (strncmp(line, drive_name_string, sizeof(drive_name_string) - 1) == 0) {
- char *device_name;
-
- device_name = strtok(skip_whitespace(line + sizeof(drive_name_string) - 1), " \t\n");
- while (device_name && device_name[0]) {
- ma = mi = -1;
- dev_get_major_minor(device_name, &ma, &mi);
- uuidcache_check_device(device_name, ma, mi, 1);
- device_name = strtok(NULL, " \t\n");
- }
- break;
- }
- }
-
- fclose(proccd);
+ return TRUE;
}
static void
@@ -297,8 +107,11 @@ uuidcache_init(void)
if (uuidCache)
return;
- uuidcache_init_partitions();
- uuidcache_init_cdroms();
+ recursive_action("/dev", ACTION_RECURSE,
+ uuidcache_check_device, /* file_action */
+ NULL, /* dir_action */
+ NULL, /* userData */
+ 0 /* depth */);
}
#define UUID 1