[Pkg-libvirt-commits] [libguestfs] 127/233: fuse: In mount-local-run, test if root filesystem has been mounted (RHBZ#1057504).

[Hilko Bengen]

This is an automated email from the git hooks/post-receive script.

bengen pushed a commit to branch experimental
in repository libguestfs.

commit 0e2489974b91e4728d544fe2aa08c2a1c9deb365
Author: Richard W.M. Jones <rjones at redhat.com>
Date:   Fri Jan 24 10:20:14 2014 +0000

    fuse: In mount-local-run, test if root filesystem has been mounted (RHBZ#1057504).
    
    It is never normally valid to use the mount-local* APIs when you
    haven't mounted some filesystems in the libguestfs namespace.
    
    If you try it, it results in some odd errors.  The mount-local-run
    call is successful, but subsequent operations fail:
    
    $ mkdir -p /tmp/mnt
    $ guestfish -x -N fs mount-local /tmp/mnt : mount-local-run
    libguestfs: error: lstat: lstat_stub: you must call 'mount' first to mount the root filesystem
    libguestfs: error: lstat: lstat_stub: you must call 'mount' first to mount the root filesystem
    
    With this commit, the mount-local-run call gives an error:
    
    libguestfs: error: you must call 'guestfs_mount' first to mount a filesystem on '/'.
    Note: '/tmp/mnt' is still mounted.  Use 'guestunmount /tmp/mnt' to clean up.
    
    The error is implemented by calling guestfs_exists (g, "/") which has
    the side effect of running the NEED_ROOT macro in the daemon.  (There
    is no simple equivalent of NEED_ROOT on the library side.)
---
 src/fuse.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/fuse.c b/src/fuse.c
index dd4f139..caf8719 100644
--- a/src/fuse.c
+++ b/src/fuse.c
@@ -1028,6 +1028,18 @@ guestfs__mount_local_run (guestfs_h *g)
     return -1;
   }
 
+  /* Test if root is mounted.  We do this by using a side-effect of
+   * guestfs_exists (which is that it calls NEED_ROOT).
+   */
+  guestfs_push_error_handler (g, NULL, NULL);
+  r = guestfs_exists (g, "/");
+  guestfs_pop_error_handler (g);
+  if (r == -1) {
+    error (g, _("you must call 'guestfs_mount' first to mount a filesystem on '/'.\nNote: '%s' is still mounted.  Use 'guestunmount %s' to clean up."),
+           g->localmountpoint, g->localmountpoint);
+    return -1;
+  }
+
   debug (g, "%s: entering fuse_loop", __func__);
 
   /* Enter the main loop. */

-- 
Alioth's /usr/local/bin/git-commit-notice on /srv/git.debian.org/git/pkg-libvirt/libguestfs.git