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Diffstat (limited to 'util-linux/umount.c')
-rw-r--r--util-linux/umount.c197
1 files changed, 142 insertions, 55 deletions
diff --git a/util-linux/umount.c b/util-linux/umount.c
index 68b27e3..b65caf7 100644
--- a/util-linux/umount.c
+++ b/util-linux/umount.c
@@ -37,11 +37,24 @@ static const char umount_usage[] =
#else
"\n"
#endif
+#ifdef BB_FEATURE_REMOUNT
+"\t-r:\tTry to remount devices as read-only if mount is busy\n"
+#endif
;
+struct _mtab_entry_t {
+ char *device;
+ char *mountpt;
+ struct _mtab_entry_t *next;
+};
+
+static struct _mtab_entry_t *mtab_cache = NULL;
+
+
static int useMtab = TRUE;
static int umountAll = FALSE;
+static int doRemount = FALSE;
extern const char mtab_file[]; /* Defined in utility.c */
#define MIN(x,y) (x > y ? x : y)
@@ -50,21 +63,10 @@ static int
do_umount(const char* name, int useMtab)
{
int status;
- struct mntent *m;
- FILE *mountTable;
- const char *blockDevice = NULL;
-
- if ((mountTable = setmntent (mtab_file, "r"))) {
- while ((m = getmntent (mountTable)) != 0) {
- if (strncmp(m->mnt_dir, name,
- MIN(strlen(m->mnt_dir),strlen(name))) == 0)
- blockDevice = m->mnt_fsname;
- else if (strcmp(m->mnt_fsname, name) == 0) {
- blockDevice = name;
- name = m->mnt_dir;
- }
- }
- }
+ char *blockDevice = mtab_getinfo(name, MTAB_GETDEVICE);
+
+ if (blockDevice && strcmp(blockDevice, name) == 0)
+ name = mtab_getinfo(blockDevice, MTAB_GETMOUNTPT);
status = umount(name);
@@ -73,57 +75,53 @@ do_umount(const char* name, int useMtab)
/* this was a loop device, delete it */
del_loop(blockDevice);
#endif
-#if defined BB_MTAB
+#if defined BB_FEATURE_REMOUNT
+ if ( status != 0 && doRemount == TRUE && errno == EBUSY ) {
+ status = mount(blockDevice, name, NULL,
+ MS_MGC_VAL | MS_REMOUNT | MS_RDONLY, NULL);
+ if (status == 0) {
+ fprintf(stderr, "umount: %s busy - remounted read-only\n",
+ blockDevice);
+ /* TODO: update mtab if BB_MTAB is defined */
+ } else {
+ fprintf(stderr, "umount: Cannot remount %s read-only\n",
+ blockDevice);
+ }
+ }
+#endif
if ( status == 0 ) {
+#if defined BB_MTAB
if ( useMtab==TRUE )
erase_mtab(name);
- return 0;
- }
- else
#endif
- return(status);
+ return( TRUE);
+ }
+ return(FALSE);
}
static int
umount_all(int useMtab)
{
- int status;
- struct mntent *m;
- FILE *mountTable;
-
- if ((mountTable = setmntent (mtab_file, "r"))) {
- while ((m = getmntent (mountTable)) != 0) {
- char *blockDevice = m->mnt_fsname;
-#if ! defined BB_MTAB
- if (strcmp (blockDevice, "/dev/root") == 0) {
- struct fstab* fstabItem;
- fstabItem = getfsfile ("/");
- if (fstabItem != NULL) {
- blockDevice = fstabItem->fs_spec;
- }
+ int status = TRUE;
+ char *mountpt;
+ void *iter;
+
+ for (mountpt = mtab_first(&iter); mountpt; mountpt = mtab_next(&iter)) {
+ status=do_umount (mountpt, useMtab);
+ if (status != 0) {
+ /* Don't bother retrying the umount on busy devices */
+ if (errno == EBUSY) {
+ perror(mountpt);
+ continue;
}
-#endif
- /* Don't umount /proc when doing umount -a */
- if (strcmp (blockDevice, "proc") == 0)
- continue;
-
- status=do_umount (m->mnt_dir, useMtab);
- if (status!=0) {
- /* Don't bother retrying the umount on busy devices */
- if (errno==EBUSY) {
- perror(m->mnt_dir);
- continue;
- }
- status=do_umount (blockDevice, useMtab);
- if (status!=0) {
- printf ("Couldn't umount %s on %s (type %s): %s\n",
- blockDevice, m->mnt_dir, m->mnt_type, strerror(errno));
- }
+ status = do_umount (mountpt, useMtab);
+ if (status != 0) {
+ printf ("Couldn't umount %s on %s: %s\n",
+ mountpt, mtab_getinfo(mountpt, MTAB_GETDEVICE), strerror(errno));
}
}
- endmntent (mountTable);
}
- return( TRUE);
+ return (status);
}
extern int
@@ -144,13 +142,18 @@ umount_main(int argc, char** argv)
useMtab = FALSE;
break;
#endif
+#ifdef BB_FEATURE_REMOUNT
+ case 'r':
+ doRemount = TRUE;
+ break;
+#endif
default:
usage( umount_usage);
}
}
-
- if(umountAll==TRUE) {
+ mtab_read();
+ if (umountAll==TRUE) {
exit(umount_all(useMtab));
}
if ( do_umount(*argv,useMtab) == 0 )
@@ -161,3 +164,87 @@ umount_main(int argc, char** argv)
}
}
+
+
+/* These functions are here because the getmntent functions do not appear
+ * to be re-entrant, which leads to all sorts of problems when we try to
+ * use them recursively - randolph
+ */
+void mtab_read(void)
+{
+ struct _mtab_entry_t *entry = NULL;
+ struct mntent *e;
+ FILE *fp;
+
+ if (mtab_cache != NULL) return;
+
+ if ((fp = setmntent(mtab_file, "r")) == NULL) {
+ fprintf(stderr, "Cannot open %s\n", mtab_file);
+ return;
+ }
+ while ((e = getmntent(fp))) {
+ entry = malloc(sizeof(struct _mtab_entry_t));
+ entry->device = strdup(e->mnt_fsname);
+ entry->mountpt = strdup(e->mnt_dir);
+ entry->next = mtab_cache;
+ mtab_cache = entry;
+ }
+ endmntent(fp);
+}
+
+char *mtab_getinfo(const char *match, const char which)
+{
+ struct _mtab_entry_t *cur = mtab_cache;
+ while (cur) {
+ if (strcmp(cur->mountpt, match) == 0 ||
+ strcmp(cur->device, match) == 0) {
+ if (which == MTAB_GETMOUNTPT) {
+ return cur->mountpt;
+ } else {
+#if !defined BB_MTAB
+ if (strcmp(cur->device, "/dev/root") == 0) {
+ struct fstab* fstabItem;
+ fstabItem = getfsfile ("/");
+ if (fstabItem != NULL) return fstabItem->fs_spec;
+ }
+#endif
+ return cur->device;
+ }
+ }
+ cur = cur->next;
+ }
+ return NULL;
+}
+
+char *mtab_first(void **iter)
+{
+ struct _mtab_entry_t *mtab_iter;
+ if (!iter) return NULL;
+ mtab_iter = mtab_cache;
+ *iter = (void *)mtab_iter;
+ return mtab_next(iter);
+}
+
+char *mtab_next(void **iter)
+{
+ char *mp;
+ if (iter == NULL || *iter == NULL) return NULL;
+ mp = ((struct _mtab_entry_t *)(*iter))->mountpt;
+ *iter = (void *)((struct _mtab_entry_t *)(*iter))->next;
+ return mp;
+}
+
+void mtab_free(void)
+{
+ struct _mtab_entry_t *this, *next;
+
+ this = mtab_cache;
+ while (this) {
+ next = this->next;
+ if (this->device) free(this->device);
+ if (this->mountpt) free(this->mountpt);
+ free(this);
+ this = next;
+ }
+}
+