diff options
Diffstat (limited to 'e2fsprogs/blkid/devname.c')
| -rw-r--r-- | e2fsprogs/blkid/devname.c | 376 |
1 files changed, 376 insertions, 0 deletions
diff --git a/e2fsprogs/blkid/devname.c b/e2fsprogs/blkid/devname.c new file mode 100644 index 0000000..87d5cbe --- /dev/null +++ b/e2fsprogs/blkid/devname.c @@ -0,0 +1,376 @@ +/* + * 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% + */ + +#include <stdio.h> +#include <string.h> +#if HAVE_UNISTD_H +#include <unistd.h> +#endif +#include <stdlib.h> +#include <string.h> +#include <ctype.h> +#if HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#if HAVE_SYS_STAT_H +#include <sys/stat.h> +#endif +#if HAVE_ERRNO_H +#include <errno.h> +#endif +#if HAVE_SYS_MKDEV_H +#include <sys/mkdev.h> +#endif +#include <time.h> + +#include "blkidP.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; + + 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(DEBUG_DEVNAME, + printf("found devname %s in cache\n", tmp->bid_name)); + dev = tmp; + break; + } + + if (!dev && (flags & BLKID_DEV_CREATE)) { + dev = blkid_new_dev(); + if (!dev) + return NULL; + dev->bid_name = blkid_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); + return dev; +} + +/* + * 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) +{ + blkid_dev dev = NULL; + struct list_head *p; + const char **dir; + char *devname = NULL; + + /* See if we already have this device number in the cache. */ + list_for_each(p, &cache->bic_devs) { + blkid_dev tmp = list_entry(p, struct blkid_struct_dev, + bid_devs); + if (tmp->bid_devno == devno) { + dev = blkid_verify(cache, tmp); + break; + } + } + if (dev && dev->bid_devno == devno) + goto set_pri; + + /* + * 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 = blkid_devdirs; *dir; dir++) { + struct stat st; + char device[256]; + + sprintf(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) && + st.st_rdev == devno) { + devname = blkid_strdup(device); + break; + } + } + if (!devname) { + devname = blkid_devno_to_devname(devno); + if (!devname) + return; + } + dev = blkid_get_dev(cache, devname, BLKID_DEV_NORMAL); + free(devname); + +set_pri: + if (!pri && !strncmp(ptname, "md", 2)) + pri = BLKID_PRI_MD; + if (dev) + dev->bid_pri = pri; + 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 +#include <dirent.h> +static dev_t lvm_get_devno(const char *lvm_device) +{ + FILE *lvf; + char buf[1024]; + int ma, mi; + dev_t ret = 0; + + DBG(DEBUG_DEVNAME, printf("opening %s\n", lvm_device)); + if ((lvf = fopen(lvm_device, "r")) == NULL) { + DBG(DEBUG_DEVNAME, printf("%s: (%d) %s\n", lvm_device, errno, + strerror(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) +{ + 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(DEBUG_DEVNAME, printf("probing LVM devices under %s\n", 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(DEBUG_DEVNAME, printf("LVM dev %s: devno 0x%04X\n", + lvm_device, + (unsigned int) dev)); + probe_one(cache, lvm_device, dev, BLKID_PRI_LVM); + 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) +{ + char line[100]; + int ma, mi, sz, num = 0; + FILE *procpt; + char device[110]; + + procpt = fopen(PROC_EVMS_VOLUMES, "r"); + 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(DEBUG_DEVNAME, printf("Checking partition %s (%d, %d)\n", + device, ma, mi)); + + probe_one(cache, device, makedev(ma, mi), BLKID_PRI_EVMS); + num++; + } + fclose(procpt); + return num; +} + +/* + * Read the device data for all available block devices in the system. + */ +int blkid_probe_all(blkid_cache cache) +{ + FILE *proc; + char line[1024]; + char ptname0[128], ptname1[128], *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; + + 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); +#ifdef VG_DIR + lvm_probe_all(cache); +#endif + + proc = fopen(PROC_PARTITIONS, "r"); + 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(DEBUG_DEVNAME, printf("read partition name %s\n", ptname)); + + /* Skip whole disk devs unless they have no partitions + * If we don't have a partition on this dev, also + * check previous dev to see if it didn't have a partn. + * heuristic: partition name ends in a digit. + * + * Skip extended partitions. + * heuristic: size is 1 + * + * FIXME: skip /dev/{ida,cciss,rd} whole-disk devs + */ + + lens[which] = strlen(ptname); + if (isdigit(ptname[lens[which] - 1])) { + DBG(DEBUG_DEVNAME, + printf("partition dev %s, devno 0x%04X\n", + ptname, (unsigned int) devs[which])); + + if (sz > 1) + probe_one(cache, ptname, devs[which], 0); + lens[which] = 0; + lens[last] = 0; + } else if (lens[last] && strncmp(ptnames[last], ptname, + lens[last])) { + DBG(DEBUG_DEVNAME, + printf("whole dev %s, devno 0x%04X\n", + ptnames[last], (unsigned int) devs[last])); + probe_one(cache, ptnames[last], devs[last], 0); + lens[last] = 0; + } + } + + /* Handle the last device if it wasn't partitioned */ + if (lens[which]) + probe_one(cache, ptname, devs[which], 0); + + fclose(proc); + + cache->bic_time = time(0); + cache->bic_flags |= BLKID_BIC_FL_PROBED; + blkid_flush_cache(cache); + return 0; +} + +#ifdef TEST_PROGRAM +int main(int argc, char **argv) +{ + blkid_cache cache = NULL; + int ret; + + blkid_debug_mask = 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]); + + blkid_put_cache(cache); + return (0); +} +#endif |