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Diffstat (limited to 'i/pc104/initrd/conf/busybox/util-linux/umount.c')
-rw-r--r--i/pc104/initrd/conf/busybox/util-linux/umount.c152
1 files changed, 152 insertions, 0 deletions
diff --git a/i/pc104/initrd/conf/busybox/util-linux/umount.c b/i/pc104/initrd/conf/busybox/util-linux/umount.c
new file mode 100644
index 0000000..4ea15d9
--- /dev/null
+++ b/i/pc104/initrd/conf/busybox/util-linux/umount.c
@@ -0,0 +1,152 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Mini umount implementation for busybox
+ *
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ * Copyright (C) 2005 by Rob Landley <rob@landley.net>
+ *
+ * Licensed under GPL version 2, see file LICENSE in this tarball for details.
+ */
+
+#include "busybox.h"
+#include <mntent.h>
+#include <getopt.h>
+
+#define OPTION_STRING "flDnravd"
+#define OPT_FORCE 1
+#define OPT_LAZY 2
+#define OPT_DONTFREELOOP 4
+#define OPT_NO_MTAB 8
+#define OPT_REMOUNT 16
+#define OPT_ALL (ENABLE_FEATURE_UMOUNT_ALL ? 32 : 0)
+
+int umount_main(int argc, char **argv);
+int umount_main(int argc, char **argv)
+{
+ int doForce;
+ char path[2*PATH_MAX];
+ struct mntent me;
+ FILE *fp;
+ int status = EXIT_SUCCESS;
+ unsigned opt;
+ struct mtab_list {
+ char *dir;
+ char *device;
+ struct mtab_list *next;
+ } *mtl, *m;
+
+ /* Parse any options */
+
+ opt = getopt32(argc, argv, OPTION_STRING);
+
+ argc -= optind;
+ argv += optind;
+
+ doForce = MAX((opt & OPT_FORCE), (opt & OPT_LAZY));
+
+ /* Get a list of mount points from mtab. We read them all in now mostly
+ * for umount -a (so we don't have to worry about the list changing while
+ * we iterate over it, or about getting stuck in a loop on the same failing
+ * entry. Notice that this also naturally reverses the list so that -a
+ * umounts the most recent entries first. */
+
+ m = mtl = 0;
+
+ /* If we're umounting all, then m points to the start of the list and
+ * the argument list should be empty (which will match all). */
+
+ fp = setmntent(bb_path_mtab_file, "r");
+ if (!fp) {
+ if (opt & OPT_ALL)
+ bb_error_msg_and_die("cannot open %s", bb_path_mtab_file);
+ } else {
+ while (getmntent_r(fp, &me, path, sizeof(path))) {
+ m = xmalloc(sizeof(struct mtab_list));
+ m->next = mtl;
+ m->device = xstrdup(me.mnt_fsname);
+ m->dir = xstrdup(me.mnt_dir);
+ mtl = m;
+ }
+ endmntent(fp);
+ }
+
+ /* If we're not umounting all, we need at least one argument. */
+ if (!(opt & OPT_ALL)) {
+ m = 0;
+ if (!argc) bb_show_usage();
+ }
+
+ // Loop through everything we're supposed to umount, and do so.
+ for (;;) {
+ int curstat;
+ char *zapit = *argv;
+
+ // Do we already know what to umount this time through the loop?
+ if (m) safe_strncpy(path, m->dir, PATH_MAX);
+ // For umount -a, end of mtab means time to exit.
+ else if (opt & OPT_ALL) break;
+ // Get next command line argument (and look it up in mtab list)
+ else if (!argc--) break;
+ else {
+ argv++;
+ realpath(zapit, path);
+ for (m = mtl; m; m = m->next)
+ if (!strcmp(path, m->dir) || !strcmp(path, m->device))
+ break;
+ }
+ // If we couldn't find this sucker in /etc/mtab, punt by passing our
+ // command line argument straight to the umount syscall. Otherwise,
+ // umount the directory even if we were given the block device.
+ if (m) zapit = m->dir;
+
+ // Let's ask the thing nicely to unmount.
+ curstat = umount(zapit);
+
+ // Force the unmount, if necessary.
+ if (curstat && doForce) {
+ curstat = umount2(zapit, doForce);
+ if (curstat)
+ bb_error_msg("forced umount of %s failed!", zapit);
+ }
+
+ // If still can't umount, maybe remount read-only?
+ if (curstat && (opt & OPT_REMOUNT) && errno == EBUSY && m) {
+ curstat = mount(m->device, zapit, NULL, MS_REMOUNT|MS_RDONLY, NULL);
+ bb_error_msg(curstat ? "cannot remount %s read-only" :
+ "%s busy - remounted read-only", m->device);
+ }
+
+ if (curstat) {
+ status = EXIT_FAILURE;
+ bb_perror_msg("cannot umount %s", zapit);
+ } else {
+ /* De-allocate the loop device. This ioctl should be ignored on
+ * any non-loop block devices. */
+ if (ENABLE_FEATURE_MOUNT_LOOP && !(opt & OPT_DONTFREELOOP) && m)
+ del_loop(m->device);
+ if (ENABLE_FEATURE_MTAB_SUPPORT && !(opt & OPT_NO_MTAB) && m)
+ erase_mtab(m->dir);
+ }
+
+ // Find next matching mtab entry for -a or umount /dev
+ // Note this means that "umount /dev/blah" will unmount all instances
+ // of /dev/blah, not just the most recent.
+ while (m && (m = m->next))
+ if ((opt & OPT_ALL) || !strcmp(path, m->device))
+ break;
+ }
+
+ // Free mtab list if necessary
+
+ if (ENABLE_FEATURE_CLEAN_UP) {
+ while (mtl) {
+ m = mtl->next;
+ free(mtl->device);
+ free(mtl->dir);
+ free(mtl);
+ mtl = m;
+ }
+ }
+
+ return status;
+}