[Libguestfs] [PATCH] mllib: hostname: on Debian replace it also in /etc/hosts (RHBZ#953907).
Richard W.M. Jones
rjones at redhat.com
Thu Feb 13 14:50:05 UTC 2014
On Thu, Feb 13, 2014 at 03:10:41PM +0100, Pino Toscano wrote:
> In Debian/Ubuntu systems, read the previous hostname from /etc/hostname
> before replacing it, and replace it in /etc/hosts with the new hostname.
> ---
> mllib/hostname.ml | 30 ++++++++++++++++++++++++++++++
> 1 file changed, 30 insertions(+)
>
> diff --git a/mllib/hostname.ml b/mllib/hostname.ml
> index fce16ff..70ca934 100644
> --- a/mllib/hostname.ml
> +++ b/mllib/hostname.ml
> @@ -42,7 +42,12 @@ let rec set_hostname (g : Guestfs.guestfs) root hostname =
> true
>
> | "linux", ("debian"|"ubuntu"), _ ->
> + let old_hostname = read_etc_hostname g in
> update_etc_hostname g hostname;
> + (match old_hostname with
> + | Some old_hostname -> replace_host_in_etc_hosts g old_hostname hostname
> + | None -> ()
> + );
> true
>
> | "linux", ("fedora"|"rhel"|"centos"|"scientificlinux"|"redhat-based"), _ ->
> @@ -78,3 +83,28 @@ and update_etc_hostname g hostname =
>
> and update_etc_machine_info g hostname =
> replace_line_in_file g "/etc/machine-info" "PRETTY_HOSTNAME" hostname
> +
> +and read_etc_hostname g =
> + let filename = "/etc/hostname" in
> + if g#is_file filename then (
> + let lines = Array.to_list (g#read_lines filename) in
> + match lines with
> + | hd :: _ -> Some hd
> + | [] -> None
> + ) else
> + None
> +
> +and replace_host_in_etc_hosts g oldhost newhost =
> + if g#is_file "/etc/hosts" then (
> + let expr = "/files/etc/hosts/*[label() != '#comment']/*[label() != 'ipaddr']" in
> + g#aug_init "/" 0;
> + let matches = Array.to_list (g#aug_match expr) in
> + List.iter (
> + fun m ->
> + let value = g#aug_get m in
> + if value = oldhost then (
> + g#aug_set m newhost
> + )
> + ) matches;
> + g#aug_save ()
> + )
Yup, third time lucky :-)
ACK.
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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