/*
* mountpoint implementation for busybox
*
- * Copyright (C) 2005 Bernhard Fischer
+ * Copyright (C) 2005 Bernhard Reutner-Fischer
*
- * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*
* Based on sysvinit's mountpoint
*/
+//usage:#define mountpoint_trivial_usage
+//usage: "[-q] <[-dn] DIR | -x DEVICE>"
+//usage:#define mountpoint_full_usage "\n\n"
+//usage: "Check if the directory is a mountpoint\n"
+//usage: "\n -q Quiet"
+//usage: "\n -d Print major/minor device number of the filesystem"
+//usage: "\n -n Print device name of the filesystem"
+//usage: "\n -x Print major/minor device number of the blockdevice"
+//usage:
+//usage:#define mountpoint_example_usage
+//usage: "$ mountpoint /proc\n"
+//usage: "/proc is not a mountpoint\n"
+//usage: "$ mountpoint /sys\n"
+//usage: "/sys is a mountpoint\n"
+
#include "libbb.h"
int mountpoint_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int mountpoint_main(int argc, char **argv)
+int mountpoint_main(int argc UNUSED_PARAM, char **argv)
{
struct stat st;
+ const char *msg;
char *arg;
- int opt = getopt32(argv, "qdx");
+ int rc, opt;
+
+ opt_complementary = "=1"; /* must have one argument */
+ opt = getopt32(argv, "qdxn");
#define OPT_q (1)
#define OPT_d (2)
#define OPT_x (4)
+#define OPT_n (8)
+ arg = argv[optind];
+ msg = "%s";
- if (optind != argc - 1)
- bb_show_usage();
+ rc = (opt & OPT_x) ? stat(arg, &st) : lstat(arg, &st);
+ if (rc != 0)
+ goto err;
- arg = argv[optind];
+ if (opt & OPT_x) {
+ if (S_ISBLK(st.st_mode)) {
+ printf("%u:%u\n", major(st.st_rdev),
+ minor(st.st_rdev));
+ return EXIT_SUCCESS;
+ }
+ errno = 0; /* make perror_msg work as error_msg */
+ msg = "%s: not a block device";
+ goto err;
+ }
- if ( (opt & OPT_x && stat(arg, &st) == 0) || (lstat(arg, &st) == 0) ) {
- if (opt & OPT_x) {
- if (S_ISBLK(st.st_mode)) {
- printf("%u:%u\n", major(st.st_rdev),
- minor(st.st_rdev));
- return EXIT_SUCCESS;
- } else {
- if (opt & OPT_q)
- bb_putchar('\n');
- else
- bb_error_msg("%s: not a block device", arg);
- }
- return EXIT_FAILURE;
- } else
- if (S_ISDIR(st.st_mode)) {
- dev_t st_dev = st.st_dev;
- ino_t st_ino = st.st_ino;
- char *p = xasprintf("%s/..", arg);
+ errno = ENOTDIR;
+ if (S_ISDIR(st.st_mode)) {
+ dev_t st_dev = st.st_dev;
+ ino_t st_ino = st.st_ino;
+ char *p = xasprintf("%s/..", arg);
- if (stat(p, &st) == 0) {
- int ret = (st_dev != st.st_dev) ||
- (st_dev == st.st_dev && st_ino == st.st_ino);
- if (opt & OPT_d)
- printf("%u:%u\n", major(st_dev), minor(st_dev));
- else if (!(opt & OPT_q))
- printf("%s is %sa mountpoint\n", arg, ret?"":"not ");
- return !ret;
+ if (stat(p, &st) == 0) {
+ //int is_mnt = (st_dev != st.st_dev) || (st_dev == st.st_dev && st_ino == st.st_ino);
+ int is_not_mnt = (st_dev == st.st_dev) && (st_ino != st.st_ino);
+
+ if (opt & OPT_d)
+ printf("%u:%u\n", major(st_dev), minor(st_dev));
+ if (opt & OPT_n) {
+ const char *d = find_block_device(arg);
+ /* name is undefined, but device is mounted -> anonymous superblock! */
+ /* happens with btrfs */
+ if (!d) {
+ d = "UNKNOWN";
+ /* TODO: iterate /proc/mounts, or /proc/self/mountinfo
+ * to find out the device name */
+ }
+ printf("%s %s\n", d, arg);
}
- } else {
- if (!(opt & OPT_q))
- bb_error_msg("%s: not a directory", arg);
- return EXIT_FAILURE;
+ if (!(opt & (OPT_q | OPT_d | OPT_n)))
+ printf("%s is %sa mountpoint\n", arg, is_not_mnt ? "not " : "");
+ return is_not_mnt;
}
+ arg = p;
+ /* else: stat had set errno, just fall through */
}
+
+ err:
if (!(opt & OPT_q))
- bb_simple_perror_msg(arg);
+ bb_perror_msg(msg, arg);
return EXIT_FAILURE;
}