[Libguestfs] [PATCH 1/2] customize: Update "unassigned-hostname" etc in Debian/Ubuntu /etc/hosts (RHBZ#1372269).
Commit ab2df2e6598d421067d600f89a3d225162424d9b attempted to rewrite
/etc/hosts if it contained the old hostname.
However this wasn't done reliably for a couple of reasons:
(1) Certain Debian/Ubuntu /etc/hostname contains
"localhost.localdomain" but still has "unassigned-hostname" or
"unassigned-hostname.unassigned-domain" in /etc/hosts.
(2) Even if (1) doesn't apply, you still need to split out the
hostname and domainname parts and deal with them separately.
---
customize/hostname.ml | 40 ++++++++++++++++++++++++++++++++--------
1 file changed, 32 insertions(+), 8 deletions(-)
diff --git a/customize/hostname.ml b/customize/hostname.ml
index d7bb54b..073604d 100644
--- a/customize/hostname.ml
+++ b/customize/hostname.ml
@@ -44,10 +44,7 @@ let rec set_hostname (g : Guestfs.guestfs) root hostname =
| "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 -> ()
- );
+ replace_host_in_etc_hosts g old_hostname hostname;
true
| "linux",
("fedora"|"rhel"|"centos"|"scientificlinux"|"redhat-based"),
_ ->
@@ -94,17 +91,44 @@ and read_etc_hostname g =
) else
None
+and aug_hosts_expr =
+ (* Matches everything in /etc/hosts except the IP address and comments. *)
+ "/files/etc/hosts/*[label() != '#comment']/*[label() !=
'ipaddr']"
+
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
+ let oldshortname, olddomainname =
+ match oldhost with
+ | None -> None, None
+ | Some oldhost ->
+ let s, d = String.split "." oldhost in Some s, Some d in
+ let newshortname, newdomainname = String.split "." newhost in
+
g#aug_init "/" 0;
- let matches = Array.to_list (g#aug_match expr) in
+ let matches = Array.to_list (g#aug_match aug_hosts_expr) in
+
List.iter (
fun m ->
let value = g#aug_get m in
- if value = oldhost then (
+
+ (* Replace either "oldhostname" or
"oldhostname.olddomainname". *)
+ if oldhost = Some value then
+ g#aug_set m newhost
+
+ else if oldshortname = Some value then
+ g#aug_set m newshortname
+
+ (* On Debian/Ubuntu we also may find "unassigned-hostname"
+ * which has to be replaced with the short hostname.
+ *)
+ else if value = "unassigned-hostname" then
+ g#aug_set m newshortname
+
+ (* Or we may find "unassigned-hostname.unassigned-domain". *)
+ else if value = "unassigned-hostname.unassigned-domain" &&
+ newdomainname <> "" then
g#aug_set m newhost
- )
) matches;
+
g#aug_save ()
)
--
2.9.3