df: fix "df /"

also, clean up mount checks in mkfs/fsck.

function                                             old     new   delta
find_mount_point                                     243     261     +18
sha1_process_block64                                 497     510     +13
find_main                                            436     444      +8
display_speed                                         85      90      +5
df_main                                              795     793      -2
parse_command                                       1463    1460      -3
static.ignored_mounts                                  8       -      -8
mkfs_minix_main                                     2962    2937     -25
fsck_minix_main                                     3065    2970     -95
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 4/4 up/down: 44/-133)           Total: -89 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

3 files changed, 25 insertions, 39 deletions

diff --git a/util-linux/fsck_minix.c b/util-linux/fsck_minix.c
index 0c33c1b02..ca0b17efe 100644
--- a/util-linux/fsck_minix.c
+++ b/util-linux/fsck_minix.c
@@ -374,38 +374,28 @@ static int ask(const char *string, int def)
  */
 static void check_mount(void)
 {
-        FILE *f;
-        struct mntent *mnt;
-        int cont;
-        int fd;
-//XXX:FIXME use find_mount_point()
-        f = setmntent(MOUNTED, "r");
-        if (f == NULL)
-                return;
-        while ((mnt = getmntent(f)) != NULL)
-                if (strcmp(device_name, mnt->mnt_fsname) == 0)
-                        break;
-        endmntent(f);
-        if (!mnt)
-                return;
-
-        /*
-         * If the root is mounted read-only, then /etc/mtab is
-         * probably not correct; so we won't issue a warning based on
-         * it.
-         */
-        fd = open(MOUNTED, O_RDWR);
-        if (fd < 0 && errno == EROFS)
-                return;
-        close(fd);
-
-        printf("%s is mounted. ", device_name);
-        cont = 0;
-        if (isatty(0) && isatty(1))
-                cont = ask("Do you really want to continue", 0);
-        if (!cont) {
-                printf("Check aborted\n");
-                exit(EXIT_SUCCESS);
+        if (find_mount_point(device_name)) {
+                int cont;
+#if ENABLE_FEATURE_MTAB_SUPPORT
+                /*
+                 * If the root is mounted read-only, then /etc/mtab is
+                 * probably not correct; so we won't issue a warning based on
+                 * it.
+                 */
+                int fd = open(bb_path_mtab_file, O_RDWR);
+
+                if (fd < 0 && errno == EROFS)
+                        return;
+                close(fd);
+#endif
+                printf("%s is mounted. ", device_name);
+                cont = 0;
+                if (isatty(0) && isatty(1))
+                        cont = ask("Do you really want to continue", 0);
+                if (!cont) {
+                        printf("Check aborted\n");
+                        exit(EXIT_SUCCESS);
+                }
         }
 }
 
diff --git a/util-linux/mkfs_minix.c b/util-linux/mkfs_minix.c
index 2666132f9..18512a395 100644
--- a/util-linux/mkfs_minix.c
+++ b/util-linux/mkfs_minix.c
@@ -624,7 +624,6 @@ static void setup_tables(void)
 int mkfs_minix_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int mkfs_minix_main(int argc UNUSED_PARAM, char **argv)
 {
-        struct mntent *mp;
         unsigned opt;
         char *tmp;
         struct stat statbuf;
@@ -683,11 +682,8 @@ int mkfs_minix_main(int argc UNUSED_PARAM, char **argv)
                 G.total_blocks = 65535;
 
         /* Check if it is mounted */
-        mp = find_mount_point(G.device_name, NULL);
-        if (mp && strcmp(G.device_name, mp->mnt_fsname) == 0)
-                bb_error_msg_and_die("%s is mounted on %s; "
-                                "refusing to make a filesystem",
-                                G.device_name, mp->mnt_dir);
+        if (find_mount_point(G.device_name))
+                bb_error_msg_and_die("can't format mounted filesystem");
 
         xmove_fd(xopen(G.device_name, O_RDWR), dev_fd);
         if (fstat(dev_fd, &statbuf) < 0)
diff --git a/util-linux/mkfs_vfat.c b/util-linux/mkfs_vfat.c
index 98a089502..8c6078d7b 100644
--- a/util-linux/mkfs_vfat.c
+++ b/util-linux/mkfs_vfat.c
@@ -275,7 +275,7 @@ int mkfs_vfat_main(int argc UNUSED_PARAM, char **argv)
                 )
                         bb_error_msg_and_die("will not try to make filesystem on full-disk device (use -I if wanted)");
                 // can't work on mounted filesystems
-                if (find_mount_point(device_name, NULL))
+                if (find_mount_point(device_name))
                         bb_error_msg_and_die("can't format mounted filesystem");
 #endif
                 // get true sector size