| /* vi: set sw=4 ts=4: */ |
| /* |
| * Utility routines. |
| * |
| * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org> |
| * |
| * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
| */ |
| |
| #include "libbb.h" |
| #include <mntent.h> |
| |
| /* |
| * Given a block device, find the mount table entry if that block device |
| * is mounted. |
| * |
| * Given any other file (or directory), find the mount table entry for its |
| * filesystem. |
| */ |
| struct mntent* FAST_FUNC find_mount_point(const char *name, int subdir_too) |
| { |
| struct stat s; |
| FILE *mtab_fp; |
| struct mntent *mountEntry; |
| dev_t devno_of_name; |
| bool block_dev; |
| |
| if (stat(name, &s) != 0) |
| return NULL; |
| |
| devno_of_name = s.st_dev; |
| block_dev = 0; |
| /* Why S_ISCHR? - UBI volumes use char devices, not block */ |
| if (S_ISBLK(s.st_mode) || S_ISCHR(s.st_mode)) { |
| devno_of_name = s.st_rdev; |
| block_dev = 1; |
| } |
| |
| mtab_fp = setmntent(bb_path_mtab_file, "r"); |
| if (!mtab_fp) |
| return NULL; |
| |
| while ((mountEntry = getmntent(mtab_fp)) != NULL) { |
| /* rootfs mount in Linux 2.6 exists always, |
| * and it makes sense to always ignore it. |
| * Otherwise people can't reference their "real" root! */ |
| if (ENABLE_FEATURE_SKIP_ROOTFS && strcmp(mountEntry->mnt_fsname, "rootfs") == 0) |
| continue; |
| |
| if (strcmp(name, mountEntry->mnt_dir) == 0 |
| || strcmp(name, mountEntry->mnt_fsname) == 0 |
| ) { /* String match. */ |
| break; |
| } |
| |
| if (!(subdir_too || block_dev)) |
| continue; |
| |
| /* Is device's dev_t == name's dev_t? */ |
| if (stat(mountEntry->mnt_fsname, &s) == 0 && s.st_rdev == devno_of_name) |
| break; |
| /* Match the directory's mount point. */ |
| if (stat(mountEntry->mnt_dir, &s) == 0 && s.st_dev == devno_of_name) |
| break; |
| } |
| endmntent(mtab_fp); |
| |
| return mountEntry; |
| } |