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-rw-r--r--libblkid/src/devname.c675
1 files changed, 675 insertions, 0 deletions
diff --git a/libblkid/src/devname.c b/libblkid/src/devname.c
new file mode 100644
index 000000000..fdbb5c99a
--- /dev/null
+++ b/libblkid/src/devname.c
@@ -0,0 +1,675 @@
+/*
+ * devname.c - get a dev by its device inode name
+ *
+ * Copyright (C) Andries Brouwer
+ * Copyright (C) 1999, 2000, 2001, 2002, 2003 Theodore Ts'o
+ * Copyright (C) 2001 Andreas Dilger
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ * %End-Header%
+ */
+
+#define _GNU_SOURCE 1
+
+#include <stdio.h>
+#include <string.h>
+#include <limits.h>
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <stdlib.h>
+#include <ctype.h>
+#include <fcntl.h>
+#ifdef HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#include <dirent.h>
+#ifdef HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#ifdef HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#include <time.h>
+
+#include "blkidP.h"
+
+#include "canonicalize.h" /* $(top_srcdir)/include */
+#include "pathnames.h"
+#include "sysfs.h"
+#include "at.h"
+
+/*
+ * Find a dev struct in the cache by device name, if available.
+ *
+ * If there is no entry with the specified device name, and the create
+ * flag is set, then create an empty device entry.
+ */
+blkid_dev blkid_get_dev(blkid_cache cache, const char *devname, int flags)
+{
+ blkid_dev dev = NULL, tmp;
+ struct list_head *p, *pnext;
+
+ if (!cache || !devname)
+ return NULL;
+
+ list_for_each(p, &cache->bic_devs) {
+ tmp = list_entry(p, struct blkid_struct_dev, bid_devs);
+ if (strcmp(tmp->bid_name, devname))
+ continue;
+
+ DBG(DEVNAME, ul_debug("found devname %s in cache", tmp->bid_name));
+ dev = tmp;
+ break;
+ }
+
+ if (!dev && (flags & BLKID_DEV_CREATE)) {
+ if (access(devname, F_OK) < 0)
+ return NULL;
+ dev = blkid_new_dev();
+ if (!dev)
+ return NULL;
+ dev->bid_time = INT_MIN;
+ dev->bid_name = strdup(devname);
+ dev->bid_cache = cache;
+ list_add_tail(&dev->bid_devs, &cache->bic_devs);
+ cache->bic_flags |= BLKID_BIC_FL_CHANGED;
+ }
+
+ if (flags & BLKID_DEV_VERIFY) {
+ dev = blkid_verify(cache, dev);
+ if (!dev || !(dev->bid_flags & BLKID_BID_FL_VERIFIED))
+ return dev;
+ /*
+ * If the device is verified, then search the blkid
+ * cache for any entries that match on the type, uuid,
+ * and label, and verify them; if a cache entry can
+ * not be verified, then it's stale and so we remove
+ * it.
+ */
+ list_for_each_safe(p, pnext, &cache->bic_devs) {
+ blkid_dev dev2 = list_entry(p, struct blkid_struct_dev, bid_devs);
+ if (dev2->bid_flags & BLKID_BID_FL_VERIFIED)
+ continue;
+ if (!dev->bid_type || !dev2->bid_type ||
+ strcmp(dev->bid_type, dev2->bid_type))
+ continue;
+ if (dev->bid_label && dev2->bid_label &&
+ strcmp(dev->bid_label, dev2->bid_label))
+ continue;
+ if (dev->bid_uuid && dev2->bid_uuid &&
+ strcmp(dev->bid_uuid, dev2->bid_uuid))
+ continue;
+ if ((dev->bid_label && !dev2->bid_label) ||
+ (!dev->bid_label && dev2->bid_label) ||
+ (dev->bid_uuid && !dev2->bid_uuid) ||
+ (!dev->bid_uuid && dev2->bid_uuid))
+ continue;
+ dev2 = blkid_verify(cache, dev2);
+ if (dev2 && !(dev2->bid_flags & BLKID_BID_FL_VERIFIED))
+ blkid_free_dev(dev2);
+ }
+ }
+ return dev;
+}
+
+/* Directories where we will try to search for device names */
+static const char *dirlist[] = { "/dev", "/devfs", "/devices", NULL };
+
+static int is_dm_leaf(const char *devname)
+{
+ struct dirent *de, *d_de;
+ DIR *dir, *d_dir;
+ char path[256];
+ int ret = 1;
+
+ if ((dir = opendir("/sys/block")) == NULL)
+ return 0;
+ while ((de = readdir(dir)) != NULL) {
+ if (!strcmp(de->d_name, ".") || !strcmp(de->d_name, "..") ||
+ !strcmp(de->d_name, devname) ||
+ strncmp(de->d_name, "dm-", 3) ||
+ strlen(de->d_name) > sizeof(path)-32)
+ continue;
+ sprintf(path, "/sys/block/%s/slaves", de->d_name);
+ if ((d_dir = opendir(path)) == NULL)
+ continue;
+ while ((d_de = readdir(d_dir)) != NULL) {
+ if (!strcmp(d_de->d_name, devname)) {
+ ret = 0;
+ break;
+ }
+ }
+ closedir(d_dir);
+ if (!ret)
+ break;
+ }
+ closedir(dir);
+ return ret;
+}
+
+/*
+ * Probe a single block device to add to the device cache.
+ */
+static void probe_one(blkid_cache cache, const char *ptname,
+ dev_t devno, int pri, int only_if_new, int removable)
+{
+ blkid_dev dev = NULL;
+ struct list_head *p, *pnext;
+ const char **dir;
+ char *devname = NULL;
+
+ /* See if we already have this device number in the cache. */
+ list_for_each_safe(p, pnext, &cache->bic_devs) {
+ blkid_dev tmp = list_entry(p, struct blkid_struct_dev,
+ bid_devs);
+ if (tmp->bid_devno == devno) {
+ if (only_if_new && !access(tmp->bid_name, F_OK))
+ return;
+ dev = blkid_verify(cache, tmp);
+ if (dev && (dev->bid_flags & BLKID_BID_FL_VERIFIED))
+ break;
+ dev = 0;
+ }
+ }
+ if (dev && dev->bid_devno == devno)
+ goto set_pri;
+
+ /* Try to translate private device-mapper dm-<N> names
+ * to standard /dev/mapper/<name>.
+ */
+ if (!strncmp(ptname, "dm-", 3) && isdigit(ptname[3])) {
+ devname = canonicalize_dm_name(ptname);
+ if (!devname)
+ blkid__scan_dir("/dev/mapper", devno, 0, &devname);
+ if (devname)
+ goto get_dev;
+ }
+
+ /*
+ * Take a quick look at /dev/ptname for the device number. We check
+ * all of the likely device directories. If we don't find it, or if
+ * the stat information doesn't check out, use blkid_devno_to_devname()
+ * to find it via an exhaustive search for the device major/minor.
+ */
+ for (dir = dirlist; *dir; dir++) {
+ struct stat st;
+ char device[256];
+
+ snprintf(device, sizeof(device), "%s/%s", *dir, ptname);
+ if ((dev = blkid_get_dev(cache, device, BLKID_DEV_FIND)) &&
+ dev->bid_devno == devno)
+ goto set_pri;
+
+ if (stat(device, &st) == 0 &&
+ (S_ISBLK(st.st_mode) ||
+ (S_ISCHR(st.st_mode) && !strncmp(ptname, "ubi", 3))) &&
+ st.st_rdev == devno) {
+ devname = strdup(device);
+ goto get_dev;
+ }
+ }
+ /* Do a short-cut scan of /dev/mapper first */
+ if (!devname)
+ blkid__scan_dir("/dev/mapper", devno, 0, &devname);
+ if (!devname) {
+ devname = blkid_devno_to_devname(devno);
+ if (!devname)
+ return;
+ }
+
+get_dev:
+ dev = blkid_get_dev(cache, devname, BLKID_DEV_NORMAL);
+ free(devname);
+
+set_pri:
+ if (dev) {
+ if (pri)
+ dev->bid_pri = pri;
+ else if (!strncmp(dev->bid_name, "/dev/mapper/", 11)) {
+ dev->bid_pri = BLKID_PRI_DM;
+ if (is_dm_leaf(ptname))
+ dev->bid_pri += 5;
+ } else if (!strncmp(ptname, "md", 2))
+ dev->bid_pri = BLKID_PRI_MD;
+ if (removable)
+ dev->bid_flags |= BLKID_BID_FL_REMOVABLE;
+ }
+ return;
+}
+
+#define PROC_PARTITIONS "/proc/partitions"
+#define VG_DIR "/proc/lvm/VGs"
+
+/*
+ * This function initializes the UUID cache with devices from the LVM
+ * proc hierarchy. We currently depend on the names of the LVM
+ * hierarchy giving us the device structure in /dev. (XXX is this a
+ * safe thing to do?)
+ */
+#ifdef VG_DIR
+static dev_t lvm_get_devno(const char *lvm_device)
+{
+ FILE *lvf;
+ char buf[1024];
+ int ma, mi;
+ dev_t ret = 0;
+
+ DBG(DEVNAME, ul_debug("opening %s", lvm_device));
+ if ((lvf = fopen(lvm_device, "r" UL_CLOEXECSTR)) == NULL) {
+ DBG(DEVNAME, ul_debug("%s: (%d) %m", lvm_device, errno));
+ return 0;
+ }
+
+ while (fgets(buf, sizeof(buf), lvf)) {
+ if (sscanf(buf, "device: %d:%d", &ma, &mi) == 2) {
+ ret = makedev(ma, mi);
+ break;
+ }
+ }
+ fclose(lvf);
+
+ return ret;
+}
+
+static void lvm_probe_all(blkid_cache cache, int only_if_new)
+{
+ DIR *vg_list;
+ struct dirent *vg_iter;
+ int vg_len = strlen(VG_DIR);
+ dev_t dev;
+
+ if ((vg_list = opendir(VG_DIR)) == NULL)
+ return;
+
+ DBG(DEVNAME, ul_debug("probing LVM devices under %s", VG_DIR));
+
+ while ((vg_iter = readdir(vg_list)) != NULL) {
+ DIR *lv_list;
+ char *vdirname;
+ char *vg_name;
+ struct dirent *lv_iter;
+
+ vg_name = vg_iter->d_name;
+ if (!strcmp(vg_name, ".") || !strcmp(vg_name, ".."))
+ continue;
+ vdirname = malloc(vg_len + strlen(vg_name) + 8);
+ if (!vdirname)
+ goto exit;
+ sprintf(vdirname, "%s/%s/LVs", VG_DIR, vg_name);
+
+ lv_list = opendir(vdirname);
+ free(vdirname);
+ if (lv_list == NULL)
+ continue;
+
+ while ((lv_iter = readdir(lv_list)) != NULL) {
+ char *lv_name, *lvm_device;
+
+ lv_name = lv_iter->d_name;
+ if (!strcmp(lv_name, ".") || !strcmp(lv_name, ".."))
+ continue;
+
+ lvm_device = malloc(vg_len + strlen(vg_name) +
+ strlen(lv_name) + 8);
+ if (!lvm_device) {
+ closedir(lv_list);
+ goto exit;
+ }
+ sprintf(lvm_device, "%s/%s/LVs/%s", VG_DIR, vg_name,
+ lv_name);
+ dev = lvm_get_devno(lvm_device);
+ sprintf(lvm_device, "%s/%s", vg_name, lv_name);
+ DBG(DEVNAME, ul_debug("LVM dev %s: devno 0x%04X",
+ lvm_device,
+ (unsigned int) dev));
+ probe_one(cache, lvm_device, dev, BLKID_PRI_LVM,
+ only_if_new, 0);
+ free(lvm_device);
+ }
+ closedir(lv_list);
+ }
+exit:
+ closedir(vg_list);
+}
+#endif
+
+#define PROC_EVMS_VOLUMES "/proc/evms/volumes"
+
+static int
+evms_probe_all(blkid_cache cache, int only_if_new)
+{
+ char line[100];
+ int ma, mi, sz, num = 0;
+ FILE *procpt;
+ char device[110];
+
+ procpt = fopen(PROC_EVMS_VOLUMES, "r" UL_CLOEXECSTR);
+ if (!procpt)
+ return 0;
+ while (fgets(line, sizeof(line), procpt)) {
+ if (sscanf (line, " %d %d %d %*s %*s %[^\n ]",
+ &ma, &mi, &sz, device) != 4)
+ continue;
+
+ DBG(DEVNAME, ul_debug("Checking partition %s (%d, %d)",
+ device, ma, mi));
+
+ probe_one(cache, device, makedev(ma, mi), BLKID_PRI_EVMS,
+ only_if_new, 0);
+ num++;
+ }
+ fclose(procpt);
+ return num;
+}
+
+static void
+ubi_probe_all(blkid_cache cache, int only_if_new)
+{
+ const char **dirname;
+
+ for (dirname = dirlist; *dirname; dirname++) {
+ DIR *dir;
+ struct dirent *iter;
+
+ DBG(DEVNAME, ul_debug("probing UBI volumes under %s",
+ *dirname));
+
+ dir = opendir(*dirname);
+ if (dir == NULL)
+ continue ;
+
+ while ((iter = readdir(dir)) != NULL) {
+ char *name;
+ struct stat st;
+ dev_t dev;
+
+ name = iter->d_name;
+#ifdef _DIRENT_HAVE_D_TYPE
+ if (iter->d_type != DT_UNKNOWN &&
+ iter->d_type != DT_CHR && iter->d_type != DT_LNK)
+ continue;
+#endif
+ if (!strcmp(name, ".") || !strcmp(name, "..") ||
+ !strstr(name, "ubi"))
+ continue;
+ if (!strcmp(name, "ubi_ctrl"))
+ continue;
+ if (fstat_at(dirfd(dir), *dirname, name, &st, 0))
+ continue;
+
+ dev = st.st_rdev;
+
+ if (!S_ISCHR(st.st_mode) || !minor(dev))
+ continue;
+ DBG(DEVNAME, ul_debug("UBI vol %s/%s: devno 0x%04X",
+ *dirname, name, (int) dev));
+ probe_one(cache, name, dev, BLKID_PRI_UBI, only_if_new, 0);
+ }
+ closedir(dir);
+ }
+}
+
+/*
+ * Read the device data for all available block devices in the system.
+ */
+static int probe_all(blkid_cache cache, int only_if_new)
+{
+ FILE *proc;
+ char line[1024];
+ char ptname0[128 + 1], ptname1[128 + 1], *ptname = 0;
+ char *ptnames[2];
+ dev_t devs[2];
+ int ma, mi;
+ unsigned long long sz;
+ int lens[2] = { 0, 0 };
+ int which = 0, last = 0;
+ struct list_head *p, *pnext;
+
+ ptnames[0] = ptname0;
+ ptnames[1] = ptname1;
+
+ if (!cache)
+ return -BLKID_ERR_PARAM;
+
+ if (cache->bic_flags & BLKID_BIC_FL_PROBED &&
+ time(0) - cache->bic_time < BLKID_PROBE_INTERVAL)
+ return 0;
+
+ blkid_read_cache(cache);
+ evms_probe_all(cache, only_if_new);
+#ifdef VG_DIR
+ lvm_probe_all(cache, only_if_new);
+#endif
+ ubi_probe_all(cache, only_if_new);
+
+ proc = fopen(PROC_PARTITIONS, "r" UL_CLOEXECSTR);
+ if (!proc)
+ return -BLKID_ERR_PROC;
+
+ while (fgets(line, sizeof(line), proc)) {
+ last = which;
+ which ^= 1;
+ ptname = ptnames[which];
+
+ if (sscanf(line, " %d %d %llu %128[^\n ]",
+ &ma, &mi, &sz, ptname) != 4)
+ continue;
+ devs[which] = makedev(ma, mi);
+
+ DBG(DEVNAME, ul_debug("read partition name %s", ptname));
+
+ /* Skip whole disk devs unless they have no partitions.
+ * If base name of device has changed, also
+ * check previous dev to see if it didn't have a partn.
+ * heuristic: partition name ends in a digit, & partition
+ * names contain whole device name as substring.
+ *
+ * Skip extended partitions.
+ * heuristic: size is 1
+ *
+ * FIXME: skip /dev/{ida,cciss,rd} whole-disk devs
+ */
+
+ lens[which] = strlen(ptname);
+
+ /* ends in a digit, clearly a partition, so check */
+ if (isdigit(ptname[lens[which] - 1])) {
+ DBG(DEVNAME, ul_debug("partition dev %s, devno 0x%04X",
+ ptname, (unsigned int) devs[which]));
+
+ if (sz > 1)
+ probe_one(cache, ptname, devs[which], 0,
+ only_if_new, 0);
+ lens[which] = 0; /* mark as checked */
+ }
+
+ /*
+ * If last was a whole disk and we just found a partition
+ * on it, remove the whole-disk dev from the cache if
+ * it exists.
+ */
+ if (lens[last] && !strncmp(ptnames[last], ptname, lens[last])) {
+ list_for_each_safe(p, pnext, &cache->bic_devs) {
+ blkid_dev tmp;
+
+ /* find blkid dev for the whole-disk devno */
+ tmp = list_entry(p, struct blkid_struct_dev,
+ bid_devs);
+ if (tmp->bid_devno == devs[last]) {
+ DBG(DEVNAME, ul_debug("freeing %s",
+ tmp->bid_name));
+ blkid_free_dev(tmp);
+ cache->bic_flags |= BLKID_BIC_FL_CHANGED;
+ break;
+ }
+ }
+ lens[last] = 0;
+ }
+ /*
+ * If last was not checked because it looked like a whole-disk
+ * dev, and the device's base name has changed,
+ * check last as well.
+ */
+ if (lens[last] && strncmp(ptnames[last], ptname, lens[last])) {
+ DBG(DEVNAME, ul_debug("whole dev %s, devno 0x%04X",
+ ptnames[last], (unsigned int) devs[last]));
+ probe_one(cache, ptnames[last], devs[last], 0,
+ only_if_new, 0);
+ lens[last] = 0;
+ }
+ }
+
+ /* Handle the last device if it wasn't partitioned */
+ if (lens[which])
+ probe_one(cache, ptname, devs[which], 0, only_if_new, 0);
+
+ fclose(proc);
+ blkid_flush_cache(cache);
+ return 0;
+}
+
+/* Don't use it by default -- it's pretty slow (because cdroms, floppy, ...)
+ */
+static int probe_all_removable(blkid_cache cache)
+{
+ DIR *dir;
+ struct dirent *d;
+
+ if (!cache)
+ return -BLKID_ERR_PARAM;
+
+ dir = opendir(_PATH_SYS_BLOCK);
+ if (!dir)
+ return -BLKID_ERR_PROC;
+
+ while((d = readdir(dir))) {
+ struct sysfs_cxt sysfs = UL_SYSFSCXT_EMPTY;
+ int removable = 0;
+ dev_t devno;
+
+#ifdef _DIRENT_HAVE_D_TYPE
+ if (d->d_type != DT_UNKNOWN && d->d_type != DT_LNK)
+ continue;
+#endif
+ if (d->d_name[0] == '.' &&
+ ((d->d_name[1] == 0) ||
+ ((d->d_name[1] == '.') && (d->d_name[2] == 0))))
+ continue;
+
+ devno = sysfs_devname_to_devno(d->d_name, NULL);
+ if (!devno)
+ continue;
+
+ if (sysfs_init(&sysfs, devno, NULL) == 0) {
+ if (sysfs_read_int(&sysfs, "removable", &removable) != 0)
+ removable = 0;
+ sysfs_deinit(&sysfs);
+ }
+
+ if (removable)
+ probe_one(cache, d->d_name, devno, 0, 0, 1);
+ }
+
+ closedir(dir);
+ return 0;
+}
+
+
+/**
+ * blkid_probe_all:
+ * @cache: cache handler
+ *
+ * Probes all block devices.
+ *
+ * Returns: 0 on success, or number less than zero in case of error.
+ */
+int blkid_probe_all(blkid_cache cache)
+{
+ int ret;
+
+ DBG(PROBE, ul_debug("Begin blkid_probe_all()"));
+ ret = probe_all(cache, 0);
+ if (ret == 0) {
+ cache->bic_time = time(0);
+ cache->bic_flags |= BLKID_BIC_FL_PROBED;
+ }
+ DBG(PROBE, ul_debug("End blkid_probe_all() [rc=%d]", ret));
+ return ret;
+}
+
+/**
+ * blkid_probe_all_new:
+ * @cache: cache handler
+ *
+ * Probes all new block devices.
+ *
+ * Returns: 0 on success, or number less than zero in case of error.
+ */
+int blkid_probe_all_new(blkid_cache cache)
+{
+ int ret;
+
+ DBG(PROBE, ul_debug("Begin blkid_probe_all_new()"));
+ ret = probe_all(cache, 1);
+ DBG(PROBE, ul_debug("End blkid_probe_all_new() [rc=%d]", ret));
+ return ret;
+}
+
+/**
+ * blkid_probe_all_removable:
+ * @cache: cache handler
+ *
+ * The libblkid probing is based on devices from /proc/partitions by default.
+ * This file usually does not contain removable devices (e.g. CDROMs) and this kind
+ * of devices are invisible for libblkid.
+ *
+ * This function adds removable block devices to @cache (probing is based on
+ * information from the /sys directory). Don't forget that removable devices
+ * (floppies, CDROMs, ...) could be pretty slow. It's very bad idea to call
+ * this function by default.
+ *
+ * Note that devices which were detected by this function won't be written to
+ * blkid.tab cache file.
+ *
+ * Returns: 0 on success, or number less than zero in case of error.
+ */
+int blkid_probe_all_removable(blkid_cache cache)
+{
+ int ret;
+
+ DBG(PROBE, ul_debug("Begin blkid_probe_all_removable()"));
+ ret = probe_all_removable(cache);
+ DBG(PROBE, ul_debug("End blkid_probe_all_removable() [rc=%d]", ret));
+ return ret;
+}
+
+#ifdef TEST_PROGRAM
+int main(int argc, char **argv)
+{
+ blkid_cache cache = NULL;
+ int ret;
+
+ blkid_init_debug(BLKID_DEBUG_ALL);
+ if (argc != 1) {
+ fprintf(stderr, "Usage: %s\n"
+ "Probe all devices and exit\n", argv[0]);
+ exit(1);
+ }
+ if ((ret = blkid_get_cache(&cache, "/dev/null")) != 0) {
+ fprintf(stderr, "%s: error creating cache (%d)\n",
+ argv[0], ret);
+ exit(1);
+ }
+ if (blkid_probe_all(cache) < 0)
+ printf("%s: error probing devices\n", argv[0]);
+
+ if (blkid_probe_all_removable(cache) < 0)
+ printf("%s: error probing removable devices\n", argv[0]);
+
+ blkid_put_cache(cache);
+ return (0);
+}
+#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-01 17:06:38 +0200