1 /* libguestfs - the guestfsd daemon
2 * Copyright (C) 2009 Red Hat Inc.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
29 /* You must mount something on "/" first, hence: */
32 /* The "simple mount" call offers no complex options, you can just
33 * mount a device on a mountpoint. The variations like mount_ro,
34 * mount_options and mount_vfs let you set progressively more things.
36 * It's tempting to try a direct mount(2) syscall, but that doesn't
37 * do any autodetection, so we are better off calling out to
42 do_mount_vfs (char *options, char *vfstype,
43 char *device, char *mountpoint)
49 IS_DEVICE (device, -1);
51 is_root = strcmp (mountpoint, "/") == 0;
53 if (!root_mounted && !is_root) {
54 reply_with_error ("mount: you must mount something on / first");
58 len = strlen (mountpoint) + 9;
62 reply_with_perror ("malloc");
66 snprintf (mp, len, "/sysroot%s", mountpoint);
69 r = command (NULL, &error,
70 "mount", "-o", options, "-t", vfstype, device, mp, NULL);
72 r = command (NULL, &error,
73 "mount", "-o", options, device, mp, NULL);
76 reply_with_error ("mount: %s on %s: %s", device, mountpoint, error);
88 do_mount (char *device, char *mountpoint)
90 return do_mount_vfs ("sync,noatime", NULL, device, mountpoint);
94 do_mount_ro (char *device, char *mountpoint)
96 return do_mount_vfs ("ro", NULL, device, mountpoint);
100 do_mount_options (char *options, char *device,
103 return do_mount_vfs (options, NULL, device, mountpoint);
106 /* Again, use the external /bin/umount program, so that /etc/mtab
110 do_umount (char *pathordevice)
112 int len, freeit = 0, r;
116 if (strncmp (pathordevice, "/dev/", 5) == 0) {
120 len = strlen (pathordevice) + 9;
124 reply_with_perror ("malloc");
127 snprintf (buf, len, "/sysroot%s", pathordevice);
130 r = command (NULL, &err, "umount", buf, NULL);
131 if (freeit) free (buf);
133 reply_with_error ("umount: %s: %s", pathordevice, err);
140 /* update root_mounted? */
146 mounts_or_mountpoints (int mp)
151 int size = 0, alloc = 0;
155 r = command (&out, &err, "mount", NULL);
157 reply_with_error ("mount: %s", err);
167 pend = strchr (p, '\n');
173 /* Lines have the format:
174 * /dev/foo on /mountpoint type ...
176 p2 = strstr (p, " on /sysroot");
179 if (add_string (&ret, &size, &alloc, p) == -1) {
184 p2 += 12; /* skip " on /sysroot" */
185 len = strcspn (p2, " ");
187 if (len == 0) /* .. just /sysroot, so we turn it into "/" */
192 if (add_string (&ret, &size, &alloc, p2) == -1) {
204 if (add_string (&ret, &size, &alloc, NULL) == -1)
213 return mounts_or_mountpoints (0);
217 do_mountpoints (void)
219 return mounts_or_mountpoints (1);
222 /* Unmount everything mounted under /sysroot.
224 * We have to unmount in the correct order, so we sort the paths by
225 * longest first to ensure that child paths are unmounted by parent
228 * This call is more important than it appears at first, because it
229 * is widely used by both test and production code in order to
230 * get back to a known state (nothing mounted, everything synchronized).
233 compare_longest_first (const void *vp1, const void *vp2)
235 char * const *p1 = (char * const *) vp1;
236 char * const *p2 = (char * const *) vp2;
237 int n1 = strlen (*p1);
238 int n2 = strlen (*p2);
247 char **mounts = NULL;
248 int size = 0, alloc = 0;
249 char *p, *p2, *p3, *pend;
251 r = command (&out, &err, "mount", NULL);
253 reply_with_error ("mount: %s", err);
263 pend = strchr (p, '\n');
269 /* Lines have the format:
270 * /dev/foo on /mountpoint type ...
272 p2 = strstr (p, " on /sysroot");
275 p3 = p2 + strcspn (p2, " ");
277 if (add_string (&mounts, &size, &alloc, p2) == -1) {
287 qsort (mounts, size, sizeof (char *), compare_longest_first);
290 for (i = 0; i < size; ++i) {
291 r = command (NULL, &err, "umount", mounts[i], NULL);
293 reply_with_error ("umount: %s: %s", mounts[i], err);
295 free_stringslen (mounts, size);
301 free_stringslen (mounts, size);
303 /* We've unmounted root now, so ... */
309 /* Mount using the loopback device. You can't use the generic
310 * do_mount call for this because the first parameter isn't a
314 do_mount_loop (char *file, char *mountpoint)
323 /* We have to prefix /sysroot on both the filename and the mountpoint. */
324 len = strlen (mountpoint) + 9;
327 reply_with_perror ("malloc");
330 snprintf (mp, len, "/sysroot%s", mountpoint);
332 len = strlen (file) + 9;
335 reply_with_perror ("malloc");
339 snprintf (buf, len, "/sysroot%s", file);
341 r = command (NULL, &error, "mount", "-o", "loop", buf, mp, NULL);
345 reply_with_error ("mount: %s on %s: %s", file, mountpoint, error);