1 files changed, 647 insertions, 0 deletions

diff --git a/libblkid/src/devname.c b/libblkid/src/devname.c
new file mode 100644
index 0000000..3f48032
--- /dev/null
+++ b/libblkid/src/devname.c
@@ -0,0 +1,647 @@
+/*
+ * 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 "fileutils.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;
+	char *cn = NULL;
+
+	if (!cache || !devname)
+		return NULL;
+
+	/* search by name */
+	list_for_each(p, &cache->bic_devs) {
+		tmp = list_entry(p, struct blkid_struct_dev, bid_devs);
+		if (strcmp(tmp->bid_name, devname) != 0)
+			continue;
+		dev = tmp;
+		break;
+	}
+
+	/* try canonicalize the name */
+	if (!dev && (cn = canonicalize_path(devname))) {
+		if (strcmp(cn, devname) != 0) {
+			DBG(DEVNAME, ul_debug("search canonical %s", cn));
+			list_for_each(p, &cache->bic_devs) {
+				tmp = list_entry(p, struct blkid_struct_dev, bid_devs);
+				if (strcmp(tmp->bid_name, cn) != 0)
+					continue;
+				dev = tmp;
+
+				/* update name returned by blkid_dev_devname() */
+				free(dev->bid_xname);
+				dev->bid_xname = strdup(devname);
+				break;
+			}
+		} else {
+			free(cn);
+			cn = NULL;
+		}
+	}
+
+	if (!dev && (flags & BLKID_DEV_CREATE)) {
+		if (access(devname, F_OK) < 0)
+			goto done;
+		dev = blkid_new_dev();
+		if (!dev)
+			goto done;
+		dev->bid_time = (uintmax_t)1 << (sizeof(time_t) * 8 - 1);
+		if (cn) {
+			dev->bid_name = cn;
+			dev->bid_xname = strdup(devname);
+			cn = NULL;	/* see free() below */
+		} else
+			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))
+			goto done;
+		/*
+		 * 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) != 0)
+				continue;
+			if (dev->bid_label && dev2->bid_label &&
+			    strcmp(dev->bid_label, dev2->bid_label) != 0)
+				continue;
+			if (dev->bid_uuid && dev2->bid_uuid &&
+			    strcmp(dev->bid_uuid, dev2->bid_uuid) != 0)
+				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);
+		}
+	}
+done:
+	if (dev)
+		DBG(DEVNAME, ul_debug("%s requested, found %s in cache", devname, dev->bid_name));
+	free(cn);
+	return dev;
+}
+
+/* Directories where we will try to search for device names */
+static const char *dirlist[] = { "/dev", "/devfs", "/devices", NULL };
+
+/*
+ * Return 1 if the device is a device-mapper 'leaf' node
+ * not holding any other devices in its hierarchy.
+ */
+static int is_dm_leaf(const char *devname)
+{
+	DIR *dir;
+	char path[NAME_MAX + 18 + 1];
+	int ret;
+
+	snprintf(path, sizeof(path), "/sys/block/%s/holders", devname);
+	if ((dir = opendir(path)) == NULL)
+		return 0;
+
+	ret = xreaddir(dir) == NULL ? 1 : 0;	/* 'leaf' has no entries */
+
+	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 = NULL;
+		}
+	}
+	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, NULL, &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, NULL, &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/", 12)) {
+			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;
+	}
+}
+
+#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;
+		size_t		len;
+
+		vg_name = vg_iter->d_name;
+		if (!strcmp(vg_name, ".") || !strcmp(vg_name, ".."))
+			continue;
+		len = vg_len + strlen(vg_name) + 8;
+		vdirname = malloc(len);
+		if (!vdirname)
+			goto exit;
+		snprintf(vdirname, len, "%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;
+
+			len = vg_len + strlen(vg_name) + strlen(lv_name) + 8;
+			lvm_device = malloc(len);
+			if (!lvm_device) {
+				closedir(lv_list);
+				goto exit;
+			}
+			snprintf(lvm_device, len, "%s/%s/LVs/%s", VG_DIR, vg_name,
+				lv_name);
+			dev = lvm_get_devno(lvm_device);
+			snprintf(lvm_device, len, "%s/%s", vg_name, lv_name);
+			DBG(DEVNAME, ul_debug("Probe 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
+
+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 (fstatat(dirfd(dir), name, &st, 0))
+				continue;
+
+			dev = st.st_rdev;
+
+			if (!S_ISCHR(st.st_mode) || !minor(dev))
+				continue;
+			DBG(DEVNAME, ul_debug("Probe 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);
+	}
+}
+
+/*
+ * This function uses /sys to read all block devices in way compatible with
+ * /proc/partitions (like the original libblkid implementation)
+ */
+static int
+sysfs_probe_all(blkid_cache cache, int only_if_new, int only_removable)
+{
+	DIR *sysfs;
+	struct dirent *dev;
+
+	sysfs = opendir(_PATH_SYS_BLOCK);
+	if (!sysfs)
+		return -BLKID_ERR_SYSFS;
+
+	DBG(DEVNAME, ul_debug(" probe /sys/block"));
+
+	/* scan /sys/block */
+	while ((dev = xreaddir(sysfs))) {
+		DIR *dir = NULL;
+		dev_t devno;
+		size_t nparts = 0;
+		unsigned int maxparts = 0, removable = 0;
+		struct dirent *part;
+		struct path_cxt *pc = NULL;
+		uint64_t size = 0;
+
+		DBG(DEVNAME, ul_debug("checking %s", dev->d_name));
+
+		devno = sysfs_devname_to_devno(dev->d_name);
+		if (!devno)
+			goto next;
+		pc = ul_new_sysfs_path(devno, NULL, NULL);
+		if (!pc)
+			goto next;
+
+		if (ul_path_read_u64(pc, &size, "size") != 0)
+			size = 0;
+		if (ul_path_read_u32(pc, &removable, "removable") != 0)
+			removable = 0;
+
+		/* ignore empty devices */
+		if (!size)
+			goto next;
+
+		/* accept removable if only removable requested */
+		if (only_removable) {
+			if (!removable)
+				goto next;
+
+		/* emulate /proc/partitions
+		 * -- ignore empty devices and non-partitionable removable devices */
+		} else {
+			if (ul_path_read_u32(pc, &maxparts, "ext_range") != 0)
+				maxparts = 0;
+			if (!maxparts && removable)
+				goto next;
+		}
+
+		DBG(DEVNAME, ul_debug("read device name %s", dev->d_name));
+
+		dir = ul_path_opendir(pc, NULL);
+		if (!dir)
+			goto next;
+
+		/* read /sys/block/<name>/ do get partitions */
+		while ((part = xreaddir(dir))) {
+			dev_t partno;
+
+			if (!sysfs_blkdev_is_partition_dirent(dir, part, dev->d_name))
+				continue;
+
+			/* ignore extended partitions
+			 * -- recount size to blocks like /proc/partitions */
+			if (ul_path_readf_u64(pc, &size, "%s/size", part->d_name) == 0
+			    && (size >> 1) == 1)
+				continue;
+			partno = __sysfs_devname_to_devno(NULL, part->d_name, dev->d_name);
+			if (!partno)
+				continue;
+
+			DBG(DEVNAME, ul_debug(" Probe partition dev %s, devno 0x%04X",
+                                   part->d_name, (unsigned int) partno));
+			nparts++;
+			probe_one(cache, part->d_name, partno, 0, only_if_new, 0);
+		}
+
+		if (!nparts) {
+			/* add non-partitioned whole disk to cache */
+			DBG(DEVNAME, ul_debug(" Probe whole dev %s, devno 0x%04X",
+				   dev->d_name, (unsigned int) devno));
+			probe_one(cache, dev->d_name, devno, 0, only_if_new, 0);
+		} else {
+			/* remove partitioned whole-disk from cache */
+			struct list_head *p, *pnext;
+
+			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) {
+					DBG(DEVNAME, ul_debug(" freeing %s", tmp->bid_name));
+					blkid_free_dev(tmp);
+					cache->bic_flags |= BLKID_BIC_FL_CHANGED;
+					break;
+				}
+			}
+		}
+	next:
+		if (dir)
+			closedir(dir);
+		if (pc)
+			ul_unref_path(pc);
+	}
+
+	closedir(sysfs);
+	return 0;
+}
+
+/*
+ * Read the device data for all available block devices in the system.
+ */
+static int probe_all(blkid_cache cache, int only_if_new, int update_interval)
+{
+	int rc;
+
+	if (!cache)
+		return -BLKID_ERR_PARAM;
+
+	if (cache->bic_flags & BLKID_BIC_FL_PROBED &&
+	    time(NULL) - cache->bic_time < BLKID_PROBE_INTERVAL) {
+		DBG(PROBE, ul_debug("don't re-probe [delay < %d]", BLKID_PROBE_INTERVAL));
+		return 0;
+	}
+
+	blkid_read_cache(cache);
+#ifdef VG_DIR
+	lvm_probe_all(cache, only_if_new);
+#endif
+	ubi_probe_all(cache, only_if_new);
+
+	rc = sysfs_probe_all(cache, only_if_new, 0);
+
+	/* Don't mark the change as "probed" if /sys not avalable */
+	if (update_interval && rc == 0) {
+		cache->bic_time = time(NULL);
+		cache->bic_flags |= BLKID_BIC_FL_PROBED;
+	}
+
+	blkid_flush_cache(cache);
+	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, 1);
+	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, 0);
+	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 = sysfs_probe_all(cache, 0, 1);
+	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