1 TODO list for libguestfs
2 ======================================================================
4 This list contains random ideas and musings on features we could add
5 to libguestfs in future.
12 The API needs more test coverage, particularly lesser-used system
15 The big unresolved issue is UID/GID mapping between guest filesystem
16 IDs and the host. It's not easy to automate this because you need
17 extra details about the guest itself in order to get to its
18 UID->username map (eg. /etc/passwd from the guest).
23 BufferIn should turn into <char *, int> and simple strings in other
24 languages that can handle 8 bit clean strings.
26 Limit on transfers would still be 2MB for these types.
27 - then implement write-file properly
29 febootstrap / debootstrap inside appliance
30 ------------------------------------------
32 This was originally proposed as a way to install new operating systems
33 in the appliance. However no one has come up with a workable
39 Complete the Haskell bindings (see discussion on haskell-cafe).
44 Complete the bind tests - must test the return values and error cases.
46 virt-inspector - make libvirt XML
47 ---------------------------------
49 It should be possible to generate libvirt XML from virt-inspector
50 data, at least partially. This would be just another output type so:
52 virt-inspector --libvirt guest.img
54 Note that recent versions of libvirt/virt-install allow guests to be
55 imported, so this is not so useful any more.
57 "Standalone/local mode"
58 -----------------------
60 Instead of running guestfsd (the daemon) inside qemu, there should be
61 an option to just run guestfsd directly.
63 The architecture in this mode would look like:
78 (1) This only makes sense if we are running as root.
80 (2) There is no console / kernel messages in this configuration, but
81 we might consider capturing stderr from the daemon.
83 (3) guestfs_config and guestfs_add_drive become no-ops.
85 Obviously in this configuration, commands are run directly on the
86 local machine's disks. You could just run the commands themselves
87 directly, but libguestfs provides a convenient API and language
88 bindings. Also deals with tricky stuff like parsing the output of the
89 LVM commands. Also we get to leverage other code such as
92 This is mainly useful from live CDs, ie. virt-p2v.
94 Should we bother having the daemon at all and just link the guestfsd
95 code directly into libguestfs?
100 [This section should be filed as bugs, but no one seems to care for
101 PPC hosts and the hardware is rapidly becoming obsolete]
103 ppc (32 bit) works with qemu from git, however there is no serial console
105 ppc64 requires extra parameters:
107 however it still fails:
108 invalid/unsupported opcode: 01 - 01 - 1a (06301e83) 00000000018c2738 1
109 invalid bits: 00400000 for opcode: 0b - 19 - 15 (2d746572) 0000000000009230
111 no serial console in ppc or ppc64 because no one can tell us what
112 console=ttyXX option to use
114 Supermin appliance to febootstrap
115 ---------------------------------
117 Supermin appliance functionality should be moved into febootstrap.
119 Ideas for extra commands
120 ------------------------
122 General glibc / core programs:
149 Other initrd-* commands
150 -----------------------
157 Simple editing of configuration files
158 -------------------------------------
160 Some easy non-Augeas methods to edit configuration files.
163 replace /etc/file key value
165 which would look in /etc/file for any instances of
171 and replace them with
177 That would solve about 50% of reconfiguration needs, and for the
178 rest you'd use Augeas, 'download'+'upload' or 'edit'.
180 RWMJ: I had a go at implementing this, but it's quite error-prone to
181 do this sort of editing inside the C-based daemon code. It's far
182 better to do it with Augeas, or else to use an external language like
188 Currently we can't do Perl "one-liners". ie. The current syntax for
189 any short Perl one-liner would be:
191 perl -MSys::Guestfs -e '$g = Sys::Guestfs->new(); $g->add_drive ("foo"); $g->launch; $g->mount ("/dev/sda1", "/"); ....'
193 You can see we're well beyond a single line just getting to the point
194 of adding drives and mounting.
198 $h = create ($filename, \"/dev/sda1\" => \"/\");
200 $h = create ([$file1, $file2], \"/dev/sda1\" => \"/\");
202 To mount read-only, add C<ro =E<gt> 1> like this:
204 $h = create ($filename, \"/dev/sda1\" => \"/\", ro => 1);
206 which is equivalent to the following sequence of calls:
208 $h = Sys::Guestfs->new ();
209 $h->set_autosync (1);
210 $h->add_drive_ro ($filename);
212 $h->mount_ro (\"/dev/sda1\", \"/\");
214 Command-line form would be:
216 perl -MSys::Guestfs=:all -e '$_=create("guest.img", "/dev/sda1" => "/"); $_->cat ("/etc/fstab");'
218 That's not brief enough for one-liners, so we could have an extra
219 autogenerated module which creates a Sys::Guestfs handle singleton
220 (the handle is an implicit global variable as in guestfish), eg:
222 perl -MSys::Guestfs::One -e 'inspect("guest.img"); cat ("/etc/fstab");'
224 How would editing files work?
230 http://man.linux-ntfs.org/ntfsclone.8.html
235 Equip guestfish with some standard images that it can load
240 Maybe it's better to create these on the fly?
246 http://search.cpan.org/~rgiersig/IO-Tty-1.08/Pty.pm
247 http://www.perlmonks.org/index.pl?node_id=582185
249 Note that pty requires cooperation inside the C code too (there are
250 two sides to a pty, and one has to be handled after the fork).
255 Pass TERM from the library, through the kernel command line, to the
258 Windows-based daemon/appliance
259 ------------------------------
261 See discussion on list:
262 https://www.redhat.com/archives/libguestfs/2009-November/msg00165.html
264 virt-grow, virt-shrink
265 ----------------------
267 Grow and shrink existing guests. The main problem comes with
268 MBR-style partitions where you have to actually copy data around the
269 disk (unless you only want to change the final partition).
274 Add -drive file=...,lock=exclusive and -drive file=...,lock=shared
276 Change libguestfs and libvirt to do the right thing, so that multiple
277 instances of qemu cannot stomp on each other.
282 For multi-level disk images such as live CDs:
283 http://rwmj.wordpress.com/2009/07/15/unpack-the-russian-doll-of-a-f11-live-cd/
285 It's possible with libguestfs to recursively look for anything that
286 might be a filesystem, mount-{,loop} it and look in those, revealing
287 anything in a disk image.
289 However this won't work easily for VM disk images in the disk image.
290 One would have to download those to the host and launch another