| 1 | /* vi: set sw=4 ts=4: */
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| 2 | /*
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| 3 | * mountpoint implementation for busybox
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| 4 | *
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| 5 | * Copyright (C) 2005 Bernhard Reutner-Fischer
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| 6 | *
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| 7 | * Licensed under GPLv2 or later, see file LICENSE in this source tree.
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| 8 | *
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| 9 | * Based on sysvinit's mountpoint
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| 10 | */
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| 11 |
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| 12 | #include "libbb.h"
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| 13 |
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| 14 | int mountpoint_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
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| 15 | int mountpoint_main(int argc UNUSED_PARAM, char **argv)
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| 16 | {
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| 17 | struct stat st;
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| 18 | const char *msg;
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| 19 | char *arg;
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| 20 | int rc, opt;
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| 21 |
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| 22 | opt_complementary = "=1"; /* must have one argument */
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| 23 | opt = getopt32(argv, "qdxn");
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| 24 | #define OPT_q (1)
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| 25 | #define OPT_d (2)
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| 26 | #define OPT_x (4)
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| 27 | #define OPT_n (8)
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| 28 | arg = argv[optind];
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| 29 | msg = "%s";
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| 30 |
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| 31 | rc = (opt & OPT_x) ? stat(arg, &st) : lstat(arg, &st);
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| 32 | if (rc != 0)
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| 33 | goto err;
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| 34 |
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| 35 | if (opt & OPT_x) {
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| 36 | if (S_ISBLK(st.st_mode)) {
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| 37 | printf("%u:%u\n", major(st.st_rdev),
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| 38 | minor(st.st_rdev));
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| 39 | return EXIT_SUCCESS;
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| 40 | }
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| 41 | errno = 0; /* make perror_msg work as error_msg */
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| 42 | msg = "%s: not a block device";
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| 43 | goto err;
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| 44 | }
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| 45 |
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| 46 | errno = ENOTDIR;
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| 47 | if (S_ISDIR(st.st_mode)) {
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| 48 | dev_t st_dev = st.st_dev;
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| 49 | ino_t st_ino = st.st_ino;
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| 50 | char *p = xasprintf("%s/..", arg);
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| 51 |
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| 52 | if (stat(p, &st) == 0) {
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| 53 | //int is_mnt = (st_dev != st.st_dev) || (st_dev == st.st_dev && st_ino == st.st_ino);
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| 54 | int is_not_mnt = (st_dev == st.st_dev) && (st_ino != st.st_ino);
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| 55 |
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| 56 | if (opt & OPT_d)
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| 57 | printf("%u:%u\n", major(st_dev), minor(st_dev));
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| 58 | if (opt & OPT_n) {
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| 59 | const char *d = find_block_device(arg);
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| 60 | /* name is undefined, but device is mounted -> anonymous superblock! */
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| 61 | /* happens with btrfs */
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| 62 | if (!d) {
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| 63 | d = "UNKNOWN";
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| 64 | /* TODO: iterate /proc/mounts, or /proc/self/mountinfo
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| 65 | * to find out the device name */
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| 66 | }
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| 67 | printf("%s %s\n", d, arg);
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| 68 | }
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| 69 | if (!(opt & (OPT_q | OPT_d | OPT_n)))
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| 70 | printf("%s is %sa mountpoint\n", arg, is_not_mnt ? "not " : "");
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| 71 | return is_not_mnt;
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| 72 | }
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| 73 | arg = p;
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| 74 | /* else: stat had set errno, just fall through */
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| 75 | }
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| 76 |
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| 77 | err:
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| 78 | if (!(opt & OPT_q))
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| 79 | bb_perror_msg(msg, arg);
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| 80 | return EXIT_FAILURE;
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| 81 | }
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