backup: restore: keep directories in /etc/pmg for inotify

By wiping the subdirectories in /etc/pmg/, we lose the inotify
watchers upon restore (/etc/pmg itself and thus most configs are
currently handled by the keep_root flag to rmtree)
This can lead to inconsistencies after restoring for parts relying on
config in a subdirectory (e.g. /etc/pmg/pbs/pbs.conf).

This patch uses File::Find (included in perl-modules-$perlver) to keep
all directories an unlink everything else.
This was chosen for future robustness over keeping an explicit list of
directories to keep, in case a new directory gets added.

quickly tested with a fifo, chardev, and socket in the directory.

an alternative approach would be to simply reload pmgdaemon/pmgproxy
upon config-restore, but that feels more likely to miss some
(potentially future) service, expecting inotify to work.

Reported-by: Fiona Ebner <f.ebner@proxmox.com>
Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
Tested-by: Fiona Ebner <f.ebner@proxmox.com>

diff --git a/src/PMG/Backup.pm b/src/PMG/Backup.pm
index a46167cca01360181204fb6fe3d78f38caa059d4..e6994c957ce7c7e65e755d9db28a982423312d64 100644 (file)
--- a/src/PMG/Backup.pm
+++ b/src/PMG/Backup.pm
@@ -4,6 +4,7 @@ use strict;
 use warnings;
 use Data::Dumper;
 use File::Basename;
+use File::Find;
 use File::Path;
 use POSIX qw(strftime);
 
@@ -306,8 +307,13 @@ sub pmg_restore {
            unlink "$dirname/config/etc/pmg/cluster.conf"; # never restore cluster config
            rmtree "$dirname/config/etc/pmg/master";
 
-           # remove current config, but keep directory for INotify
-           rmtree("/etc/pmg", { keep_root => 1 });
+           # remove current config, but keep directories for INotify
+           File::Find::find({ wanted => sub {
+               if ( ! -d $File::Find::name) {
+                   unlink($File::Find::name) || die "removing $File::Find::name failed: $!\n";
+               }
+           }}, '/etc/pmg');
+
            # copy files
            system("cp -a $dirname/config/etc/pmg/* /etc/pmg/") == 0 ||
                die "unable to restore system configuration: ERROR";